An Evaluation of
Flexographic Inks
on Wide-Web Film
SUMMARY BOOKLET
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Pointed on Recycled Paper
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An Evaluation of
Flexographic Inks on Wide-Web Film:
Summary Booklet
t^e$>/
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U.S.EPA
Design for the Environment Program
Economics, Exposure, and Technology Division
Office of Pollution Prevention and Toxics (7404)
U.S. Environmental Protection Agency
EPA 744-R-02-002
April, 2002
Developed in partnership with the following associations:
tif) Association
napim
CRLIFORNIfl
FILM XTRUDfiS
& CONVeRTRS
RSSOC1RTION
An Evaluation of Flexographic Inks on Wide-Web Film
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Contents
Acknowledgments
For More Information
3
5
INTRODUCTION TO THE FLEXO INK STUDY
1 What is the flexo ink study about?
2 What conclusions did the study reach?
6
9
DETAILS OF THE FLEXO INK STUDY
3 Which chemicals showed concerns for health risk?
Definitions of risk used in the study
4 How did the three ink systems compare?
Health risk concerns
Performance
Materials consumption, energy use, and emissions
Operating costs
5 Solvent-based inks: Chemical category findings
6 Water-based inks: Chemical category findings
7 UV-cured inks: Chemical category findings
8 What workplace safety hazards were found?
9 What aquatic toxicity concerns were identified?
12
13
21
21
23
24
27
29
31
33
35
37
ADDITIONAL INFORMATION
Inks in the study
Methodology of the flexo ink study
Environmental resources
Pollution prevention tips for flexo professionals
References
40
44
47
54
58
An Evaluation of Flexographic Inks on Wide-Web Film
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Acknowledgments
DfE would like to thank many individuals and organizations for their participation in
this project, especially:
The Flexo Project Steering Committee
The Flexo Project Technical Committee
Industry Contributors to the Flexo Project Performance Demonstrations
The DfE Partners, particularly the Steering Committee, include the major associa-
tions in the flexographic ink industry. These partners are an excellent source of infor-
mation on both industry trends and concerns. Their willingness to maintain contin-
ued partnership with DfE over the years demonstrates their commitment to providing
the industry with sound environmental information. Associations are considered
essential DfE partners both during a project as well as for industry-wide communica-
tion and implementation of project results. Associations are key to sharing informa-
tion, including incentives to making change and recognition of businesses that have
made environmental improvements.
Steering Committee
Robert Bateman
(representing California Film Extruders
& Converters Association, and the
Film & Bag Federation)
Roplast Industries
3155 South 5th Avenue
Oraville, CA 95965
phone: 530-532-9500
fax: 530-532-9576
rbateman@roplast.com
Karen Chu
U.S. Environmental Protection Agency
1200 Pennsylvania Avenue, NW
Mail Code 7406
Washington, DC 20460
phone: 202-564-8773
fax: 202-564-8893
chu.karen@epa.gov
Norma Fox
California Film Extruders & Converters
Association
2402 Vista Nobleza
Newport Beach, CA 92660
phone: 949-644-7659
fax:949-640-9911
nsfox@earthlink.net
George Fuchs
National Association of Printing Ink
Manufacturers
581 Main St.
Woodbridge, NJ 07095-1104
phone: 732-855-1525
fax: 732-855-1838
gfuchs@napim.org
Doreen Monteleone
Flexographic Technical Association
900 Marconi Avenue
Ronkonkoma, NY 11779-7212
phone: 631-737-6020
fax:631-737-6813
dmonteleone@flexography.org
Gary Cohen
RadTech International, N.A.
3 Bethesda Metro Center, Suite 700
Bethesda, MD 20814
phone: 301-664-8408
fax: 917-464-8173
uveb@radtech.org
Ram Singhal
Flexible Packaging Association
971 Corporate Boulevard, Suite 403
Linthicum, MD 21090
phone: 410-694-0800
fax: 410-694-0900
rsinghal@flexpack.org
An Evaluation of Flexographic Inks on Wide-Web Film
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Technical Committee
A.J. Daw Printing Ink Co.*
Abt Associates Inc.
Akzo Nobel Inks Corp.*
American Inks and Coatings
Anguil Environmental Systems, Inc.
Automated Packaging*
Bema Film Systems, Inc.
Bryce Corporation*
Cello-Foil Products, Inc.*
Coast Converters
Curwood, Inc.
Deluxe Packages*
Dispersion Specialties, Inc.
DuPont Cyrel
Duralam, Inc.
E.I. du Pont de Nemours & Co.*
Emerald Packaging*
Enercon Industries Corp*
Fine Line Graphics*
Flex Pack*
Flint Ink*
Fusion UV Systems, Inc.
Georgia-Pacific
Hallmark Cards
Harper Corporation of America*
Highland Supply Corporation
Huron River Watershed Council
International Paper
INX International Ink Co.*
Kidder, Inc.
Lawson Mardon Packaging USA*
MacDermid Graphic Arts*
Maine Poly, Inc.*
MEGTEC Systems
Mobil Chemical Corp.*
Orange Plastics
Pechiney Plastic Packaging
P-F Technical Services, Inc.
Precision Printing & Packaging, Inc.
Printpack, Inc.
Progressive Inks*
Research Triangle Institute
Roplast Industries*
SC Johnson Polymer
Sericol
Strout Plastics
Sun Chemical Corporation*
U.S. EPA
UCB Chemicals
University of Tennessee
Waste Management and Research
Center
Western Michigan University
Windmueller & Hoelscher Corp.*
* These companies voluntarily supplied materials for the CTSA or participated in the
performance demonstrations.
An Evaluation of Flexographic Inks on Wide-Web Film
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For More Information
To learn more about the Design for the Environment (DfE) Flexography Partnership
or the DfE Program, or to download any of DfE's documents, visit
www. e p a. g o v/d f e
or contact us at
202-564-8780
dfe@epa.gov
To order additional printed copies of this document or other DfE publications,
contact
U.S. Environmental Protection Agency
National Service Center for Environmental Publications
PO. Box 42419
Cincinnati, OH 45242-2419
Phone: 800-490-9198
513-489-8190
Fax: 513-489-8695
e-mail: ncepimal@one.net
Internet: www.epa.gov/ncepihom/ordering.htm
Disclaimer
This document presents findings and analysis of a voluntary, cooperative effort
between the flexographic printing industry and the U.S. EPA. This is not an official
guidance document and should not be relied on by companies in the printing indus-
try to determine regulatory requirements. Information on cost and product usage in
this document was provided by individual product vendors and has not been corrobo-
rated by EPA. Mention of specific company names or products does not constitute
an endorsement by EPA.
Flexo Publications
Flexographic Ink Options: A
Cleaner Technologies Substitutes
Assessment (CTSA)
Vol 1: EPAEPA744-R-02-001-A
Vol 2: EPAEPA744-R-02-001-B
An Evaluation of Flexographic
Inks on Wide-Web Film:
Summary Booklet
EPA 744-R-02-002
Developing Cleaner Ink
Formulations: A Flowchart for Ink
Formulators (brochure)
EPA 744-F-02-003
Options for Cleaner Flexo Inks:
Highlights from the Flexo CTSA
(brochure)
EPA 744-F-02-004
Reducing VOCs in Flexography
(case study)
EPA744-F-96-013
Learning from Three Companies
that Reduced VOC Emissions
(case study)
EPA744-F-96-016
Inside Flexo: A Cleaner Run for
the Money (video)
(EPA744-V-98-001)
An Evaluation of Flexographic Inks on Wide-Web Film
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INTRODUCTION TO
THE FLEXO INK
STUDY
^M
What is the flexo ink study about?
The objective of the CTSA was to
develop as complete, systematic,
and unbiased a picture as possi-
ble of different flexo ink tech-
nologies, thereby helping
industry incorporate environmen-
tal and health information into
their ink decisions.
Flexographic Ink Options: A
Cleaner Technologies Substitutes
Assessment (CTSA) can be down-
loaded from the DfE website
(www.epa.gov/dfe). For printed
copies, contact EPA's National
Service Center for Environmental
Publications (NCEPI). Ask for:
Vol 1: EPAEPA744-R-02-001-A
Vol 2: EPAEPA744-R-02-001-B
Flexo professionals can benefit
from a better understanding of
the possible health and environ-
mental concerns of ink chemi-
cals.
This booklet summarizes the key findings of the Flexography Partnership's recent
technical report, Flexographic Ink Options: A Cleaner Technologies Substitutes
Assessment (CTSA). The complete CTSA documents a detailed research study com-
paring the environmental impacts, health risks, performance, and costs of the three
main flexo ink systems (solvent-based, water-based, and ultraviolet [UV]-cured).
Where the CTSA details performance, cost, and environment, this booklet focuses
on the environmental and health findings of the study, for two reasons:
First, printers often tend to be less familiar with health and environmental
concerns than with cost and performance issues.
Second, the study found a wide range of environmental, health, and safety
concerns for all three ink systems, and it is important for printers to become
more familiar with these concerns so that they can reduce exposure and
related risks to flexo workers, the surrounding community, and the natural
environment. Furthermore, taking such steps has the potential to conserve
materials and resources, with the potential to reduce costs.
This booklet, which summarizes important findings of the flexo ink study, was devel-
oped for managers of flexo printing facilities and ink formulators, as well as for other
decision-makers about flexo ink products. The booklet, as well as other materials
published about the flexo ink study, can help flexo professionals to:
understand more about comparative chemical risks in inks, including identify-
ing concerns for unregulated chemicals in inks that present opportunities for
proactive, voluntary risk management,
facilitate the use and formulation of cleaner inks, and
encourage adoption of workplace practices that minimize health and environ-
mental risks from exposure to chemicals of concern, and may reduce the
burden of regulatory compliance.
How the Flexo Partnership began
Because flexo facilities use so much ink, collectively they have a major environmental
impact. Historically, most flexo inks have been solvent-based, with high levels of
volatile organic compounds (VOCs) and other toxic chemicals. The industry has
made great progress in addressing environmental and health concerns of inks through
reformulation, add-on pollution control devices, and other improvements to opera-
tions and materials. However, for the benefit of flexo workers, the surrounding com-
munity, and the environment, we need to gain a better understanding of the possible
health and environmental concerns of ink chemicals.
An Evaluation of Flexographic Inks on Wide-Web Film
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Because of such concerns, the Design for the Environment (DfE) Program at the
U.S. Environmental Protection Agency (EPA) joined forces with the flexo industry on
a comprehensive, comparative assessment of environmental and health impacts, cost,
and performance of a cross-section of inks.
In designing the study, DfE formed the "flexo partnership" with over 60 participants
representing flexo associations, printers, ink suppliers, and universities. The partner-
ship elected to focus on inks because they are a major use and cost category for print-
ers, and because the many small flexo firms might not have the resources or expertise
to research the environmental implications of inks. The overarching goal of the part-
nership was to obtain a broader understanding of the environmental and health
impacts of ink chemicals, as well as to encourage the innovation and use of even
cleaner, safer inks.
Planning the Flexo Ink Study
The partners agreed to perform a cleaner technologies substitutes assessment for
flexo inks. The objective of the CTSA was to develop as complete, systematic, and
unbiased a picture as possible of different flexo ink technologies, thereby helping
industry incorporate environmental and health information into their ink decisions.
The study compared environmental and health impacts, performance, and cost of the
three primary flexo ink systems when printing film substrates on wide-web presses.
Because of their long-standing use by flexo printers, solvent-based inks were used as
the "baseline," and water-based and UV-cured inks were compared to the baseline
inks. When the study began, some project participants wanted to learn whether any
ink system showed clear advantages in terms of health, safety, or environmental
aspects. Thus, the study looked at the ink systems, as well as analyzing the chemicals
and chemical categories of the inks within those systems. The project focused on
inks used on film because flexography particularly the packaging sector prints a
wide variety of products on nonporous substrates. The partners hoped that this
choice would help make the findings more directly useful to as many flexo printers as
possible.
The research focused specifically on inks printed on film, because of the special tech-
nical and environmental challenges for printers presented by this combination,
including chemical emissions, worker health and safety issues, and some hazardous
waste concerns. The three types of film were chosen because they correspond to
important flexo market segments:
LDPE (low-density polyethelene), used for shopping bags and bread bags,
PE/EVA (polyethylene/ethyl vinyl acetate) co-extruded film, used for frozen
food bags, and
OPP (oriented polypropylene), used for snack food bags and candy wrappers.
Partners volunteered information about forty-five different ink formulations, which
then were analyzed to give a comparative, screening-level assessment of the chemical
toxicity, exposure, and health risks across the three ink systems. Altogether, the proj-
What Is Flexo?
Flexography is a large, vibrant
industry creating many products
that are used every day by virtu-
ally everyone. Take a look at
these facts about flexo:
U.S. flexo firms had annual
sales of approximately $50
billion in 1999. 1
The sector employs about
30,000 people. 2
More than 80% of all flexo
firms have fewer than 50
employees.
Flexo has an annual growth
rate of about 6%. 3
Flexo printing consumed more
than 513 million pounds of
ink in 2000. 4
Flexible film packaging
accounts for nearly 20% of
the flexo market and is valued
at $20 billion annually. 5
Flexography is used primarily for
printing on paper, corrugated
paperboard, and flexible plastic
materials. Flexo is well suited to
printing on flexible and non-
uniform surfaces (such as plastic
films and corrugated board).
Many common products are
printed using flexo, such as
snack food and frozen food
bags, labels for medicines and
personal care products, newspa-
pers, drink bottles, and cereal
containers.
When the study was conducted,
UV-cured inks were not being
used commercially to a signifi-
cant extent to print film substrates
on wide-web presses.
An Evaluation of Flexographic Inks on Wide-Web Film
-------
ect identified and studied more than 100 chemicals that were found in these ink for-
mulations. The formulas chosen were considered typical ink formulations used in
each system. The costs of buying and using these inks were studied, as was the energy
consumed in printing with these inks. Also, printed test samples were subjected to 18
distinct performance tests that covered a wide variety of conditions important to
many flexo printers. However, the study was not meant to cover every possible ink
formulation, performance category, or substrate type. Rather, it gives an in-depth
"snapshot" of flexo inks. Nonetheless, the completed study is thought to be the most
comprehensive research available on flexo inks, and it is an important resource in
undertaking changes that could benefit workers, the environment, and the bottom
line.
Notably, the Partnership designed the Flexo CTSA as a comparative study, rather than
as an optimization study, because Project Partners saw optimization as the purview of
individual printers. Partners recommended conducting the performance demonstra-
tions at 500 feet per minute, a speed that they felt all three systems could run at with
acceptable performance. Printers who run their presses at faster speeds are likely to
experience lower operating costs and higher ink use, emissions, worker exposure, and
risks than those found in the CTSA. In this sense, the flexo ink study should be con-
sidered a conservative assessment.
8
An Evaluation of Flexographic Inks on Wide-Web Film
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2
What conclusions did the study reach?
The study compared environmental and health impacts, performance, and costs of
the three primary flexo ink systems: solvent-based, water-based, and UV-cured inks.
Environmental impacts included aquatic toxicity, emissions, energy use, resource con-
sumption, and human health effects. The health impacts included estimated expo-
sure and comparative risks to pressroom and prep-room workers and residents of sur-
rounding communities, as well as safety hazards.
Some water-based and UV-cured
ink formulations demonstrated
improvements in worker safety,
reduced concerns for health and
environmental risk, and lower
material costs.
Overall findings
No ink system was superior across performance, environmental, health, and cost
criteria, although each system had advantages.
The study found a wide range of environmental, health, and safety (EH&S) charac-
teristics of formulations in solvent-based, water-based, and UV-cured ink systems.
This highlights the need for the flexo industry to work to identify and develop ink
formulations that have superior EH&S profiles while still meeting performance
needs.
Performance
Materials, equipment, and process need to be customized for each ink formulation,
substrate, and printing situation.
All three ink systems performed acceptably, but each system showed a notable range
of results on the 18 performance tests that were conducted. Results sometimes varied
depending on the test site or the ink color. Substrate type also played a major role in
performance, indicating that the ink-substrate relationship was very important to ink
performance. The many variations in performance indicate the importance of cus-
tomizing materials, equipment, and process for each ink formulation, substrate, and
printing situation.
Health concerns
None of the ink systems was predicted to pose clear concerns for health risks to peo-
ple in surrounding communities. However, all ink systems contained chemicals of
clear concern for health risks to flexo pressroom and prep-room workers, as well as
safety hazards.1
About 25% of the chemicals studied showed clear concerns for systemic or develop-
iPressroom workers were exposed via both inhalation and dermal routes; prep-room work-
ers, however, were exposed via the dermal route only.
The study's health findings rein-
force the need for adequate ven-
tilation and for flexo workers to
wear appropriate gloves and
other personal protective equip-
ment when working with inks.
The findings also underscore the
importance of developing
improved formulations that
reduce the EH&S concerns of ink
chemicals.
An Evaluation of Flexographic Inks on Wide-Web Film
-------
mental risks to workers under the conditions of the study. Chemicals showed risk
concerns to workers via both inhalation (breathing) and dermal (skin) exposure
routes. The study shows that it is not reasonable to assume an ink product is "safe"
or "risk free" without knowing more about the chemicals in the product as well as the
hazards associated with those chemicals and expected exposure to the product.
It is important to store and use
chemicals properly, to avoid acci-
dental releases that may end up
in water systems. Inks and their
wastes should never be put down
the drain.
Aquatic toxicity
Over half of the ink chemicals studied showed a high or medium hazard to aquatic
environments.
It is important to store and use chemicals properly, to avoid accidental or intentional
releases that may end up in water systems. Inks and their wastes should never be put
down the drain. Caution should be taken as well with equipment cleaning.
Consumption of materials
The UV-cured systems consumed the least ink and press-side additions.
The solvent-based ink systems used, on average, about twice the materials (inks and
press-side additions) as the water-based inks and four times the materials as the UV-
cured inks.
Ink-related emissions
Even with oxidizers, the solvent-based ink systems had higher VOC emissions than
the other two systems, on average.
As expected, water-based inks had a much lower VOC content than solvent-based
inks. Interestingly, despite the fact that they used oxidizers, the solvent-based systems
generated considerable uncaptured emissions, leading to much higher total ink-relat-
ed emissions. The water-based systems were, however, the only ones in the study
that contained listed hazardous air pollutants (HAPs). Because many inks and press-
side additions (especially those in solvent-based and water-based inks) contain VOCs
and HAPS, reducing the use of these materials may also lower the amounts of pollu-
tants, both uncaptured (fugitive) emissions in the pressroom and stack emissions that
are released outside the facility.
Energy consumption
The water-based systems consumed the least energy.
The solvent-based systems used the most energy to produce the same square footage
of image, because they used energy-consuming oxidizers to destroy hazardous com-
pounds. The water-based systems consumed the least energy, because they used nei-
ther oxidizers nor UV-curing equipment. The energy used by the UV-cured systems
10
An Evaluation of Flexographic Inks on Wide-Web Film
-------
was only slightly higher than that of the water-based inks and was approximately 22%
less than that of solvent-based inks.
Energy-related air emissions
The water-based ink systems had the lowest releases of energy-related emissions.
Releases of polluting air emissions were associated with the facility's energy source.
Emissions were highest for the UV-cured systems, because they depended entirely
upon electricity, which releases more pollutants per unit of substrate printed than
does natural gas. So, even though the UV-cured systems used only slightly more ener-
gy than the water-based systems, they contributed a larger share of pollutants based
upon that energy use. By knowing more about the environmental impacts that can be
attributed to the printing process a flexo facility uses, printers can plan ways to
appropriately reduce energy use and related environmental releases. Employing more
energy-efficient technologies may benefit a facility by reducing production costs, low-
ering energy-related emissions, and improving the facility's public image.
By knowing more about the envi-
ronmental impacts that can be
attributed to the printing process
a flexo facility uses, printers can
plan ways to appropriately
reduce energy use and related
environmental releases.
Employing more energy-efficient
technologies may benefit a facil-
ity by reducing production costs,
lowering energy-related emis-
sions, and improving the facility's
public image.
Operating costs
Press speed was the most important driver of operating costs.
UV-cured inks in the study had the highest operating costs due to the higher cost of
materials and energy, whereas water-based inks had the lowest costs. The UV-cured
inks cost 29-46% more than the water-based inks, whereas the solvent-based inks cost
1% to 39% more than the water-based inks. Although the water-based systems had
the lowest energy and capital costs, they did not use oxidizers, which would have
added to these costs.
In addition to these specific findings, the study found press speed to be a critical
driver of overall operating costs, because it affected all costs except inks and sub-
strates.
The bottom line
The flexo ink study found that each of the ink systems studied had a range of differ-
ent advantages, as well as health and environmental concerns. Considerable variation
was noted even among different colors within a single ink product line. Thus, select-
ing the best formulations is just as important for a printer as selecting an ink system.
To identify the "right mix" of ink products for a specific facility, flexo professionals
need to consider many different EH&S aspects environmental hazards, exposure
to potentially harmful products, safety considerations, and the type of energy used
as well as performance, cost, substrate, press design, and operating conditions.
To be a good proactive decision-maker, it is critical to have the best information
available. Developing and choosing product formulations with more positive envi-
ronmental profiles may require extra care and scrutiny, especially when selecting raw
materials.
Selecting the best formulations is
just as important for a printer as
selecting an ink system.
Acceptable performance is a crit-
ical characteristic of any environ-
mentally preferable technology.
Printers should work with their
suppliers to select cleaner inks
that deliver important perform-
ance characteristics.
An Evaluation of Flexographic Inks on Wide-Web Film
11
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DETAILS OF THE
FLEXO INK STUDY
The flexo ink study provides
screening-level information about
risks to human health and the
environment associated with
each ink system, and offers a
basis for comparison. Chemicals
predicted to pose a clear
concern for health risk in a
screening-level assessment are
good candidates for a more rig-
orous assessment.
The model used for the study
showed that there would be
little exposure to the general
population.
Exposure was "modeled"
that is, it was not based on
actual measurements of
releases. The study made
assumptions about a hypotheti-
cal model facility, most of
which reflect typical operating
conditions. Under a different
set of assumptions, the findings
might have been different.
Some important assumptions
follow.
30% of VOCs released to
air would be uncaptured
emissions, and 70% would
be stack emissions.
Solvent-based ink systems
would have a catalytic oxi-
dizer with a 95% destruc-
tion efficiency.
Pressroom and prep-room
workers would work a 7.5
hour shift, 250 days/year.
Pressroom and prep-room
workers would have
routine two-hand contact
(no gloves) with ink unless
a substance was corrosive.
Press speed would be 500
feet per minute.
3
Which chemicals showed concerns for health
risk?
Chemicals in flexo inks have the potential to affect workers and the wider communi-
ty around flexo facilities. The study analyzed potential risks under certain operating
conditions, and found concerns for pressroom and prep-room workers in all three ink
systems. This indicates the need for flexo professionals to take steps to address worker
health concerns as well as the opportunity to make improvements in ink formula-
tions. This chapter identifies the chemicals and chemical categories in the flexo inks
that were found to have risk concerns under the conditions of the study. First, howev-
er, it explains the aspects of risk that the flexo ink study examined.
Information about human health risk
The health risk concerns posed by ink chemicals can be systemic, developmental, or
carcinogenic. Systemic toxicity refers to adverse effects on any organ system (such as
the lungs or the nervous system). Developmental toxicity means adverse effects that
may occur to a developing organism any time between conception and sexual maturi-
ty. Developmental toxicity can manifest itself in a number of ways, ranging from
altered growth or structural (physical) abnormalities to death. Carcinogenic effects
are malignant tumors caused by cancer.
This study examined systemic and developmental effects, but it was not able to iden-
tify cancer risks for the ink chemicals because of insufficient quantitative data.
Although some chemicals in the study had some evidence of carcinogenicity (such as
tumors in experimental animals), none were known to cause cancer when touched or
inhaled.
It is important to realize that risk depends both on the toxicity of a chemical and on
the amount of it to which people and the environment are exposed. Thus, risk varies
for different ink product lines and formulations. Risk also changes depending upon
how inks are handled. As an example, if all workers wear appropriate gloves whenever
they handle inks, dermal exposure is largely removed (except for accidental spills on
other parts of the body), and so almost all dermal risks will be eliminated. Risk also
may vary depending on the quality of pollution control equipment and the pressroom
ventilation rate. For all these reasons, the risk concerns found in the study will not
necessarily match those in a particular printing facility.
12
An Evaluation of Flexographic Inks on Wide-Web Film
-------
Definitions of risk used in the study
Clear concern for risk indicates that for the chemical in question under the
assumed exposure conditions of the study, adverse effects were predicted to
occur.
Potential concern for risk indicates that for the chemical in question under the
assumed exposure conditions, adverse effects may occur.
Low or negligible concern for risk indicates that for the chemical in question
under the assumed exposure conditions, no adverse effects were expected.
The criteria for each level of risk are shown in Table 1.
TABLE 1 Criteria for Risk Levels*
Level of
Concern for
Risk
CLEAR
Hazard
Quotient
Margin of
Exposure
NOAEL LOAEL
SAT Hazard
Rating
1 to 10
ItolO MODERATE-HIGH
Potential
1 to 10
> 1 0 to 100 > 100 to 1,000 low-moderate
Low or negligible < 1
>100
> 1,000
low
* This column presents the level of risk concern if exposure is expected. If exposure is not
expected, the level of risk concern is assumed to be low or negligible.
Risk depends both on the toxicity
of a chemical and the amount of
it to which people and the envi-
ronment are exposed. Risk
varied by the product line, for-
mulation, and how inks were
handled. As an example, workers
in the study were assumed to not
wear gloves. However, if all
workers were to wear appropri-
ate gloves whenever they handle
inks, dermal exposure would
largely be removed (except for
accidental spills on other parts of
the body), and thus almost all
dermal risks would be elimi-
nated. Risk also may vary
depending on the quality of pol-
lution control equipment and the
pressroom ventilation rate. For
all these reasons, the risk con-
cerns found in the study will not
necessarily match those in a par-
ticular printing facility.
2 Hazard Quotient (HQ) is the ratio of the average daily dose (ADD) to the Reference
Dose (RfD) or Reference Concentration (RfC), where RfD and RfC are defined as the
lowest daily human exposure that is likely to be without appreciable risk of non-cancer
toxic effects during a lifetime. The more the HQ exceeds 1, the greater the level of con-
cern. HQ values below 1 imply that adverse effects are not likely to occur.
Margin of Exposure (MOE) is calculated when a RfD or RfC is not available. MOE is the
ratio of the No Observed Adverse Effect Level (NOAEL) or Lowest Observed Adverse
Effect Level (LOAEL) of a chemical to the estimated human dose or exposure level. The
NOAEL is the level at which no significant adverse effects are observed. The LOAEL is
the lowest concentration at which adverse effects are observed. The MOE indicates the
magnitude by which the NOAEL or LOAEL exceeds the estimated human dose or expo-
sure level. High MOE values (e.g., greater than 100 for a NOAEL-based MOE or greater
than 1,000 for a LOAEL-based MOE) imply a low level of risk. As the MOE decreases,
the level of risk increases.
Information for some chemicals was incomplete. In these cases, systemic toxicity con-
cerns were ranked by EPAs Structure Activity Team (SAT) according to the following cri-
teria: high concern evidence of adverse effects in humans, or conclusive evidence of
severe effects in animal studies; moderate concern suggestive evidence of toxic effects
in animals; or close structural, functional, and/or mechanistic analogy to chemicals with
known toxicity; low concern chemicals not meeting the above criteria.
An Evaluation of Flexographic Inks on Wide-Web Film
13
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Every ink product line in the
study contained chemicals that
showed clear risk concerns for
workers in the pressroom and
prep-room.
Although some chemicals in the
study had some evidence of car-
cinogenicity (such as tumors in
experimental animals), the study
was not able to identify cancer
risks for these chemicals because
of insufficient quantitative data.
Substantial use of some press-
side additives may contribute to
potential worker health concerns.
Findings about chemical risk
Under the conditions of the study, certain chemicals in each ink system were predict-
ed to pose a clear occupational risk to workers. Table 2 lists the chemical categories
and chemicals showing clear risk concern for workers, as well as exposure routes and
toxicological endpoints for each chemical.
Alcohols contained the most chemicals of clear concern for risk in the solvent-based
and water-based ink formulations.
Systemic and developmental effects that have been reported in the medical literature
(from animal or human studies) in association with use of a chemical are known as
toxic endpoints. Neurotoxic effects, eye irritation, lung effects, decreased growth, and
increased mortality are just a few examples of possible toxic endpoints. Toxic end-
points provide an idea of the kinds of adverse effects on body organ systems that may
occur from exposure to a chemical.
All chemical categories except olifin polymers included one or more chemicals that
were predicted to pose a risk concern for flexo workers. Ten solvents presented clear
risk concerns for workers. This was the largest number of chemicals serving any one
ink function. Thus, the solvents in solvent-based and water-based inks deserve
scrutiny to determine whether they may present risks to the workers in flexo facili-
ties. Several amides or nitrogenous compounds in water-based formulations present-
ed a clear concern for systemic risks to workers. The acrylated polyols contained
four chemicals posing a clear concern for risk in the UV-cured formulations.
The use of press-side additions, such as solvents and additives, increased the worker
risk concern for many of the solvent- and water-based ink formulations. In particu-
lar, propanol and propylene glycol methyl ether in solvent-based systems, as well as
ammonia, propanol, isobutanol, and ethyl carbitol in water-based systems, presented
potential or clear worker risk concerns when used in the volumes observed during
the performance demonstrations.
14
An Evaluation of Flexographic Inks on Wide-Web Film
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TABLE 2 Flexo Ink Chemicals Showing Clear Risk Concerns for Flexo Workers
(under conditions of the CTSA)
Chemical Function Exposure Toxic Endpoints**
in Ink Route*
Acrylated polymers (found in UV system)
Glycerol pro pox/ late
t ria cry late
UV reactive
compound
derm
tissue necrosis, decreased body weight, neurotoxic and respiratory effects
Acrylated polyols (found in UV system)
Dipropylene glycol
diacrylate
1,6-Hexanediol
diacrylate
Hydroxypropyl
aery late
Trimethylolpropane
triacrylate
UV reactive
compound
UV reactive
compound
UV reactive
compound
UV reactive
compound
inhal,
derm
inhal,
derm
inhal,
derm
derm
SAT: genotoxicity, neurotoxicity, oncogenicity; developmental and
reproductive effects; derm and respiratory sensitization; skin and eye
irritation
developmental effects
respiratory effects
decreased body weight; skin and neurotoxic effects; changes in clinical
chemistry; altered organ weights; respiratory effects
Alcohols (found in all systems)
Ethanol
Isobutanol
Isopropanol
Solvent
Solvent
Solvent
inhal,
derm
inhal
inhal,
derm
blood, liver, neurotoxic, and reproductive effects, decreased cellularity of
the spleen, thymus, and bone marrow; dev: fetal malformations
blood and neurotoxic effects, changes in enzyme levels; dev: cardiac septal
defects
blood and skin effects, tissue necrosis; kidney, liver, neurotoxic,
reproductive, spleen, and respiratory effects; changes in enzyme levels and
clinical and urine chemistry; dev: fetal death, musculo skeletal
abnormalities, fetotoxicity
Alkyl acetates (found in all systems)
Butyl acetate
Ethyl acetate
Solvent
Solvent
inhal,
derm
inhal
changes in serum chemistry, fluctuations in blood pressure; dev:
fetotoxicity, musculoskeletal abnormalities
blood, cardiovascular, gastrointestinal, kidney, liver, neurotoxic, and
respiratory effects; decreased spleen and liver weight; increased adrenal,
lung, and kidney weight
Amides or nitrogenous compounds (found in all systems)
Ammonia
Ammonium
hydroxide
Ethanolamine
Hydroxylamine
derivative
Multiple
Multiple
Multiple
Multiple
inhal,
derm
inhal,
derm
inhal,
derm
inhal,
derm
skin and eye irritation; corneal, liver, spleen, and respiratory effects
eye effects, nasal irritation, respiratory effects
respiratory irritation; kidney, liver, neurotoxic, and respiratory effects
SAT: genotoxicity, dermal sensitization, developmental toxicity
An Evaluation of Flexographic Inks on Wide-Web Film
15
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TABLE 2 Flexo Ink Chemicals Showing Clear Risk Concerns for Flexo Workers
Chemical Function Exposure Toxic Endpoints**
in Ink Route*
Ethylene glycol ethers (found in water system)
Alcohols, Cll-15-
secondary,
ethoxylated
Butyl carbitol
Ethyl carbitol
Solvent
Solvent
Solvent
derm
inhal,
derm
inhal,
derm
Overall concern; severe skin irritation, eye irritation, lung effects
blood and skin effects, liver effects
decreased food consumption, bladder, blood, kidney, liver, neurotoxic,
reproductive, and spleen effects; dev: sperm, liver, brain, and birth weight
in offspring***
Hydrocarbons low molecular weight (found in solvent and water systems)
n- Heptane
Multiple
inhal
auditory and neurotoxic effects, altered serum chemistry
Inorganics (solvent and water systems)
Barium
Solvent
derm
decreased body weight, increased arterial blood pressure, reproductive
and respiratory effects; dev: reduced survival, decreased weight gain,
blood effects
Organic acids or salts (found in solvent and water systems)
Dioctyl
sulfosuccinate,
sodium salt
Additive
derm
death, gastrointestinal and neurotoxic effects; dev: body weight effects;
(SAT) derm sensitizerto humans***
Organophosphorous compounds (found in solvent and UV systems)
Phosphine oxide,
bis(2,6-
dimethoxybenzoyl)
(2,4,4-
trimethylpentyl)-
Multiple
derm
neurotoxic, food consumption and body weight, adrenal, blood, skin, and
liver effects***
Organotitanium compounds (found in solvent system)
Isopropoxyethoxy-
titanium bis
(acetylacetonate)
Titanium
diisopropoxide
bis(2,4-
pentanedionate)
Additive
Additive
derm
derm
SAT: neurotoxicity, genotoxicify, oncotoxicity, and developmental/
reproductive toxicity. Skin, eye, mucous membrane irritant
SAT: irritation of the eyes, skin, and mucous membranes. Moderate
concern based on release of hydrolysis products: 2,4 pentanedione,
inorganic titanium, and isopropanol. 2,4 pentanedione: concern for
neurotoxicity, mutagenicity, oncogenicity, and developmental/reproductive
toxicity. Inorganic titanium: concern for mutagenicity and oncogenicity.
Isopropanol: concern for liver, neurotoxic, reproductive, respiratory, and
spleen effects; changes in enzyme levels and clinical and urine chemistry;
fetal death, musculoskeletal abnormalities, fetotoxicity, blood and skin
effects, tissue necrosis at application site, increased kidney and liver weight.
16
An Evaluation of Flexographic Inks on Wide-Web Film
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Chemical
Titanium
isopropoxide
Function
in Ink
Additive
Exposure
Route*
derm
Toxic Endpoints*1
irritation of the eyes, skin, and mucous membranes. Moderate concern
based on release of the hydrolysis products, inorganic titanium and
isopropanol. Inorganic titanium: concern for mutagenicity and
oncogenicity. Isopropanol: concern for liver, neurotoxic, reproductive,
respiratory, and spleen effects; changes in enzyme levels and clinical and
urine chemistry; fetal death, musculoskeletal abnormalities, fetotoxicity,
blood and skin effects, tissue necrosis at application site, increased kidney
and liver weight.
Pigments organic (found in all systems)
C.I. Pigment Red 23 Colorant
derm
blood, kidney, and stomach effects*
Pigments organometallic (found in all systems)
D&C Red No. 7
Colorant
derm
thymus and reproductive effects, changes in clinical chemistry, kidney
effects, decreased thymus weight***
Propylene glycol ethers (found in solvent and water systems)
Propylene glycol
methyl ether
Solvent
inhal,
derm
increased mortality; blood, developmental, liver, neurotoxic, reproductive,
respiratory, and skin effects; altered organ weights; and decreased growth
These chemicals were predicted to pose risk concerns under the specific conditions of this study; they might be associated with
different risks, or with no risk at all, under different conditions.
Abbreviations: dev = developmental effects. All endpoints not specifically indicated as developmental are systemic.
SAT = Structure Activity Team and acute data reports.
*Only pressroom workers were assumed to have exposure via inhalation (inhal). Both prep-room and pressroom workers were assumed to
have dermal exposure (derm).
**Toxicological endpoints are the potential effects on organ systems (e.g., cardiac, respiratory) that have been reported in the medical litera-
ture and other reports in association with use of a chemical. A reported association does not mean that the effect is necessarily caused by
the chemical.
**Reported effects may have been observed from a different exposure route.
An Evaluation of Flexographic Inks on Wide-Web Film
17
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Aspects of inks to learn
more about
Press-side additions
Cleaning products
Air emissions (VOCs and HAPs)
Safety hazards (e.g.,
flam mobility, ignitability,
reactivity, corrosivity)
Environmental hazards
Health risks to workers
Health risks to community
Energy consumption and
opportunities for conservation
Solid wastes
Unregulated chemicals
Untested chemicals
The databases and resources
listed at the back of this booklet
identify chemical substances by
specific chemical name. It is
important to obtain the correct
chemical identification informa-
tion, which includes Chemical
Abstract Service (CAS) names
and numbers when doing
research on chemical formula-
tions.
Ways to reduce health risks of flexo inks
Inhalation risks to flexo workers can be managed to a great extent by ensuring good
ventilation in the pressroom and prep-rooms, and by creating and enforcing clear
policies for use of masks and respirators. Dermal risks can be managed by making
sure that all workers wear the right gloves whenever they are handling inks, press-side
additions, or cleaners.
Many of the substances analyzed in the study were found in multiple ink formulations
and are likely to be found in other inks as well. Risks posed by ink chemicals can con-
tinue to exist as long as toxic chemicals are present and being used. Therefore,
whether choosing among the ink systems or choosing an ink formulation, it is impor-
tant to consider the EH&S impacts of the chemical substances that make up a for-
mulated product. The flexo ink study can serve as a first step in bringing a more pos-
itive environmental profile into the printing shop.
Health considerations are as basic to good printing as are performance and cost.
Identifying chemicals that have lower toxicities provides important opportunities to
remove these chemicals from formulations before they can enter the workplace and
the environment. In addition, moving to chemicals with reduced impacts will
increase environmental and health benefits. Possible benefits of switching to a clean-
er ink formulation may include
reduced health and safety risk concerns for workers and the community,
fewer regulatory requirements,
greater customer satisfaction,
increased efficiency,
a move to innovative technologies, and
lower operating costs while maintaining high quality standards.
Flexo professionals play an important role in minimizing the impacts of ink chemi-
cals. This responsibility extends beyond the walls of facilities to the greater commu-
nity and the environment. Ensuring that workers wear appropriate protective gear is
just the starting point. Only a very small percentage of the perhaps 80,000 chemicals
available for commercial use today have been adequately tested for health and envi-
ronmental hazards. More than half of the chemicals in the flexo ink study had no lit-
tle or no published toxicological data available at the time of the study. Many chemi-
cals that are not regulated by any U.S. government organization were predicted to
present a clear or possible risk concern to workers under the conditions of the study.
The inadequacy of much chemical data points to the importance of learning more
about the categories and specific chemicals in flexo inks and related products. It is
important to support research on untested and inadequately tested flexo ink chemi-
cals, especially those with clear or potential risk concerns and those produced in high
quantities. Very little basic toxicity information is publicly available on most of the
commercial chemicals made and used in the United States. Without this basic haz-
ard information, it is hard to make sound judgments about what risks these chemicals
could present to people and the environment.
18
An Evaluation of Flexographic Inks on Wide-Web Film
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Flexo professionals can and should work to identify and use formulations that will
help protect workers and the environment. The DfE Program encourages printers,
ink manufacturers, and distributors to actively engage in a dialog on "getting the right
mix" in flexo facilities. Printers and suppliers need to work together to evaluate inks,
identify possible alternatives, and compare current and alternative ink products. This
may yield benefits for printers and formulators, as well as providing benefits for work-
ers and the environment.
The Material Data Safety Sheet (MSDS) and the product label are excellent places to
start in understanding the potential impacts of a chemical. However, the MSDS or
label may not provide enough information to make a better choice. Often, chemicals
are generically described by chemical class or by trade name. Structural and other
differences in chemicals of the same general class and makeup may not be apparent
from product literature or labels, especially for imported substances. Descriptions in
distributor or supplier literature and catalogs may define a chemical type, but not
detail an actual chemical structure (e.g., whether a carbon chain is branched or linear
a key distinction from an environmental standpoint since linear chains biodegrade
more rapidly than branched). Also, sales materials may only list trade names, often
an imprecise descriptor, since a name might remain the same while the actual prod-
uct composition may change.
Table 3 lists some ways that flexo professionals can reduce risks and improve environ-
mental responsibility related to ink chemicals.
Because any given printing facility
may use different inks and have
different operating conditions
than those of the Flexo CTSA,
these chemicals may not pose a
clear concern at that facility.
However, a facility that does work
with chemicals studied by the
CTSA should carefully assess their
use and potentia worker expo-
sure, and manage appropriately.
There are approximately 2,800
high-production-volume (HPV)
chemicals for which little data
are available. HPV chemicals are
those manufactured in, or
imported into, the US in amounts
equal to or exceeding 1 million
pounds per year. To provide
important data, EPA challenged
industry to provide testing or
further information about these
chemicals. In response, many of
the HPV chemicals have been
ponsored by industry, and EPA
hopes to have all HPV testing
completed by 2004.
An Evaluation of Flexographic Inks on Wide-Web Film
19
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TABLE 3
Ways to Reduce Environmental, Health, and Safety Concerns of Ink
Chemicals
The DfE Program has developed
an Integrated Environmental
Management System (IEMS)
Implementation Guide that helps
businesses plan, set up, and
maintain an IEMS. You may
download it from the DfE website
(www.epa.gov/dfe), or contact
EPA's National Service Center for
Environmental Publications. The
publication number is EPA 744-R-
00-011.
Ensure that all workers who handle inks wear appropriate personal protective
gear (e.g., butyl or nitrile gloves and respirators as needed) to minimize expo-
sure to chemicals. More information on which gloves to choose for working
with specific chemicals can be found at the National Toxicology Program
website: http://ntp-server.niehs.nih.gov
Maximize good ventilation, particularly in ink prep-rooms and pressrooms.
Develop other safety policies and practices for inks, and ensure that workers
follow them.
Make environmental and health information about ink chemicals more acces-
sible and understandable (e.g., expand MSDSs, provide best practice tips,
include chemical information in sales materials).
Become familiar with environmental and health impacts of chemicals in inks.
Select the cleanest inks that make business sense.
Minimize use of hazardous inks as well as press-side additions.
Ensure that all pollution control devices are maintained properly and work cor-
rectly at all times.
Look at all steps in the printing process throughout the facility to identify ways
to improve operations and environmental performance. If not already in
process, start developing an environmental management system.
Support further research on ink chemicals.
20
An Evaluation of Flexographic Inks on Wide-Web Film
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4
How did the three ink sysfems compare?
The three ink systems were analyzed in terms of health risk concerns for flexo workers
and the surrounding population, performance characteristics, environmental impacts
(including emissions and material and energy use), and costs.
Health risk concerns
The flexo ink study assessed possible risks for both dermal and inhalation exposure to
chemicals. Each ink system was found to contain chemicals that, under presumed
conditions, showed clear health risk concerns for workers who handle inks in the
prep-room or pressroom.
Every ink product line in the
study contained chemicals that
showed clear risk concerns for
workers in the pressroom and
prep-room.
General population
No chemicals in the study presented a clear concern for risk to the general population
(people living near a printing facility), and most chemicals presented a negligible
concern. Each ink system, however, had one category with chemicals that posed a
potential concern for the general population: alcohols (functioning as solvents) in one
solvent-based and two water-based formulations, and acrylated polyols in one UV-
cured ink formulation (serving as reactive diluents). Based on reports by EPA's
Structure Activity Team3 (SAT), some propylene glycol ethers in one solvent-based
ink, amides or nitrogenous compounds in two UV-cured inks, and acrylated polyols in
one UV-cured ink may pose a potential risk concern to the general population.
Pressroom and prep-room workers
Every ink product line in the study contained chemicals that, under presumed condi-
tions, showed clear risk concerns for workers in the pressroom and prep-room.
One way to compare the relative risk of the three ink systems is to rank formulations
by the number or percent of chemicals predicted to pose a clear concern for worker
risk. As shown in Table 4, the solvent- and water-based product lines4 each included
an average of 16 chemicals with clear risk concern. The total number of chemicals in
an ink product line was determined by adding the numbers of base chemical ingredi-
ents and press-side solvents and additives for each formulation within a product line,
and then summing the totals for all five formulations. Using this method, a chemical
3 Information for some chemicals was incomplete. In these cases, systemic toxicity con-
cerns were ranked by EPA's Structure Activity Team (SAT).
4 A product line is a group of inks that is made by one manufacturer, shares certain print-
ing characteristics, includes multiple colors, and is intended to be used with one ink sys-
tem. For the flexo ink study, each product line contained five colorsblue, white, cyan,
magenta, and green.
Risk depends both on the toxicity
of a chemical and the amount of
it to which people and the envi-
ronment are exposed. Risk
varied by the product line, for-
mulation, and how inks were
handled. As an example, to help
identify cleaner formulations,
workers in the study were
assumed to not wear gloves.
However, if all workers were to
wear appropriate gloves when-
ever they handle inks, dermal
exposure would largely be
removed (except for accidental
spills on other parts of the body),
and thus almost all dermal risks
would be eliminated. Risk also
may vary depending on the
quality of pollution control
equipment and the pressroom
ventilation rate. For all these
reasons, the risk concerns found
in the study will not necessarily
An Evaluation of Flexographic Inks on Wide-Web Film
21
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4
How did the three ink sysfems compare?
The three ink systems were analyzed in terms of health risk concerns for flexo workers
and the surrounding population, performance characteristics, environmental impacts
(including emissions and material and energy use), and costs.
Health risk concerns
The flexo ink study assessed possible risks for both dermal and inhalation exposure to
chemicals. Each ink system was found to contain chemicals that, under presumed
conditions, showed clear health risk concerns for workers who handle inks in the
prep-room or pressroom.
Every ink product line in the
study contained chemicals that
showed clear risk concerns for
workers in the pressroom and
prep-room.
General population
No chemicals in the study presented a clear concern for risk to the general population
(people living near a printing facility), and most chemicals presented a negligible
concern. Each ink system, however, had one category with chemicals that posed a
potential concern for the general population: alcohols (functioning as solvents) in one
solvent-based and two water-based formulations, and acrylated polyols in one UV-
cured ink formulation (serving as reactive diluents). Based on reports by EPA's
Structure Activity Team3 (SAT), some propylene glycol ethers in one solvent-based
ink, amides or nitrogenous compounds in two UV-cured inks, and acrylated polyols in
one UV-cured ink may pose a potential risk concern to the general population.
Pressroom and prep-room workers
Every ink product line in the study contained chemicals that, under presumed condi-
tions, showed clear risk concerns for workers in the pressroom and prep-room.
One way to compare the relative risk of the three ink systems is to rank formulations
by the number or percent of chemicals predicted to pose a clear concern for worker
risk. As shown in Table 4, the solvent- and water-based product lines4 each included
an average of 16 chemicals with clear risk concern. The total number of chemicals in
an ink product line was determined by adding the numbers of base chemical ingredi-
ents and press-side solvents and additives for each formulation within a product line,
and then summing the totals for all five formulations. Using this method, a chemical
3 Information for some chemicals was incomplete. In these cases, systemic toxicity con-
cerns were ranked by EPA's Structure Activity Team (SAT).
4 A product line is a group of inks that is made by one manufacturer, shares certain print-
ing characteristics, includes multiple colors, and is intended to be used with one ink sys-
tem. For the flexo ink study, each product line contained five colorsblue, white, cyan,
magenta, and green.
Risk depends both on the toxicity
of a chemical and the amount of
it to which people and the envi-
ronment are exposed. Risk
varied by the product line, for-
mulation, and how inks were
handled. As an example, to help
identify cleaner formulations,
workers in the study were
assumed to not wear gloves.
However, if all workers were to
wear appropriate gloves when-
ever they handle inks, dermal
exposure would largely be
removed (except for accidental
spills on other parts of the body),
and thus almost all dermal risks
would be eliminated. Risk also
may vary depending on the
quality of pollution control
equipment and the pressroom
ventilation rate. For all these
reasons, the risk concerns found
in the study will not necessarily
An Evaluation of Flexographic Inks on Wide-Web Film
21
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TABLE 4 Number of Chemicals with Clear Worker Risk Concern*
Ink type Product Line Number Toxicological SAT Data** Total Chemicals of
of Chemicals* Data** Clear Risk Concern**
No. % No. % No. % Rank***
Solvent-
based
Water-
based
JV-cured
#S1
#S2
#W1
#W2
#W3
#W4
#U1
#U2
#U3
63
70
71
75
43
48
62
56
66
48
70
46
15
14
15
18
16
13
15
13
18
1
16
0
24%
20%
21%
24%
37%
27%
24%
23%
27%
2%
23%
0%
2
0
0
0
0
3
0
0
0
6
5
9
3%
0%
0%
0%
0%
6%
0%
0%
0%
13%
7%
20%
17
14
15
18
16
16
15
13
18
7
21
9
27%
20%
21%
24%
37%
33%
24%
23%
27%
15%
30%
20%
5
10
9
7
1
2
6
8
4
12
3
11
* Chemicals are counted more than once if found in more than one formulation within the same product line.
The number of chemicals may also include site-specific press-side solvents or additives.
** Includes clear concern for risk for systemic or developmental effects via inhalation or dermal routes.
*** The ranking orders the product lines from the highest to lowest percentage of chemicals with clear con-
cern for occupational risk.
was counted more than once if it were found in more than one formulation. For
example, ethanol, used in three formulations within a product line, was considered to
be three "chemicals." However, if a chemical presented a clear risk concern for both
dermal and inhalation pathways in a single formulation, it was counted only once.
Similarly, if a chemical presented a clear risk concern for both systemic and develop-
mental effects, it was counted only once.
This ranking demonstrates the range of worker health characteristics within any given
system. For example, the UV-cured system had the two "cleanest" product lines, as
well as the third worst. Thus, selecting the best formulations is just as important for a
printer as selecting an ink system. Printers should work with their suppliers to identify
cleaner formulations that meet their performance needs.
22
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Performance
The performance of the ink systems was evaluated by printing a representative test
image at 11 volunteer facilities. Each of the study's nine product lines (two solvent-
based, four water-based, and three UV-cured) was printed on three substrates (LDPE,
OPP, and PE/EVA). Up to 18 standard performance tests were conducted on each ink-
substrate combination to analyze a wide range of capabilities.
Table 5 lists the ink system, color, and substrate combinations showing "best in class"
performance for selected tests that were run. Most of these tests do not have indus-
try standards, and for some tests the determination of a better or worse result can
depend on the needs of a specific printing situation.
The quality of performance varied widely across ink systems, substrates, and ink for-
mulations. No clear evidence emerged that any one ink system performed best over-
all. For example,
Water-based inks outperformed solvent-based inks on both LDPE and
PE/EVA substrates. Solvent-based inks performed better than water-based
inks on the adhesive lamination test.
Gloss was highest for solvent-based inks on PE/EVA. Gloss was low on UV-
cured inks, despite the fact that high gloss is considered a strength of UV fin-
ishes.
Odors varied in both strength and type across both ink and substrate type.
Mottle was significantly higher for water-based inks, as well as for blue inks
overall. Mottle results for UV-cured inks were better than that of the water-
based inks and comparable to that of the solvent-based inks.
UV-cured inks displayed good resistance to blocking, particularly on PE/EVA
and no-slip LDPE.
UV-cured inks displayed relatively good trapping.
Coating weight was greater for UV-cured inks, despite lower ink consumption.
(This may indicate that UV-cured inks need higher linecount anilox rolls than
were used in the study.)
Substrate type was important to quality, and ink-substrate interactions such as wet-
ting and adhesion affected some of the results.
These performance demonstra-
tions were intended to provide a
snapshot of the capabilities of the
ink-substrate combinations. They
are not a substitute for thorough
facility-specific testing to deter-
mine which ink system or product
line performs best for a given
printer or print job.
The study's
performance tests:
Adhesive lamination
Block resistance
CIE L*a*b*
Coating weight
Coefficient of friction
Density
Dimensional stability
Gloss
Heat resistance/heat sea
Ice water crinkle adhesion
Image analysis
Jar odor
Mottle/lay
Opacity
Rub resistance
Tape adhesiveness
Trap
Uncured residue (UV-cured inks
only)
An Evaluation of Flexographic Inks on Wide-Web Film
23
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TABLE 5 Selected "Best in Class" Performances on Flexo CTSA Tests
Test
Adhesive lamination
Block resistance
Density
Gloss
Heat resistance
Ice water crinkle
Image analysis
Mottle
Rub resistance, wet
Best Score
0.3040 kg (highest)
1 .0 (lowest)
2. 17 (highest)
59.08 (highest)
0 failures (lowest)
no ink removal (least)
324 jJm2 dot area
(lowest)
47 (lowest)
0 failures at 1 0 strokes
This score represents the opposite end of the range
indicator of the wide range in scores on many tests.
UV-cured samples were not tested.
Results were not color-specific.
Ink System
solvent
UV no slip
UV high slip
solvent
**
solvent
solvent,water
solvent
UV no slip
water, solvent
of all scores rece
Substrate
OPP
LDPE
LDPE
PE/EVA
OPP
LDPE,
PE/EVA
PE/EVA
LDPE
LDPE,
PE/EVA
ved on this test
Color
N/A***
N/A
blue
N/A
N/A
N/A
cyan
green
N/A
for all ink
Worst Score* **
0.2575 kg (lowest)
3.2 (highest)
1 .09 (lowest)
32.31 (lowest)
24 failures (most)
30% ink removal
(most)
1 ,050 [Jm2
(highest)
812 (highest)
failure at 2.2
strokes
systems tested, as an
Materials consumption, energy use, and emissions5
Flexo printing, like many industries, consumes resources and releases pollutants to
the environment. The study sought to determine the relative impacts of the three
ink systems by examining the following:
Materials used (i.e., inks and press-side additions).
Energy consumed by press equipment specifically related to inks, including hot
air drying systems, catalytic oxidizers, corona treaters, and UV curing systems.
Pollutants released during the operation of this equipment, including carbon
dioxide, carbon monoxide, dissolved solids, hydrocarbons, nitrogen oxides, par-
ticular matter, solid wastes, sulfur oxides, and sulfuric acid.
Table 6 shows the average quantity of materials and energy consumed, as well as
energy-related pollutants released, for each ink system.
5The releases from energy use were estimated using computer modeling, rather than being
measured at each facility.
24
An Evaluation of Flexographic Inks on Wide-Web Film
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TABLE 6 Materials Used, Energy Used, and Energy-Related Emissions Generated*
Ink System Materials Used Energy Used All Energy-Related
(Ink & Press-side per 6,000 ft2 (Btu) Emissions
Additions)(lb/6,000 ft2) (g/6,000 ft2)
Solvent-based 8.53
Water-based 4.14
UV-cured 2.16
* These calculations assumed a
1 00,000 1 0,000
73,000 6,800
78,000 1 8,000
press speed of 500 feet per minute.
Ink- Related
Emissions
(g/6,000 ft2)
824
158
190
Materials consumed
In general, the UV-cured systems used the lowest volume of materials, whereas the
solvent-based systems used about four times this amount on average. These results
are consistent with the general expectation that less UV-cured ink is needed because
nearly all of the ingredients are incorporated into the dried coating, unlike for sol-
vent-based and water-based inks. Also, except for one site, no press-side additions
were used with the UV-cured systems.
Ink-related air emissions
For solvent-based and water-based systems, printers often make use of press-side
additions. These materials can add to the VOC content of the ink and may pose clear
pressroom worker risks. For example, at one of the flexo ink study sites using water-
based inks, over half of the emissions resulted from materials added at press side.
Many inks and press-side additions (especially in solvent-based and water-based inks)
contain VOCs and HAPs as a percentage of volume. VOC content was highest on
average for the solvent-based ink systems. The averaged smog-related emissions
from the water-based systems (221 grams/6,000 square feet) and UV-cured systems
(300g/6,000ft2) were considerably lower than those from the solvent-based systems
(914g/6,000ft2). This is because the water-based inks had substantially lower levels
of VOCs than solvent-based systems, and the UV-cured inks had almost no VOCs.
Therefore, despite the fact that the solvent-based systems used oxidizers, they gener-
ated considerable uncaptured emissions, leading to much higher ink-related emis-
sions.
The water-based systems were the only ones in the study that contained HAPs.
Water-based printing systems that do not use oxidizers may therefore release HAPs as
both uncaptured emissions in the facility and as stack emissions to the environment
outside the facility.
Reducing the amounts of ink-related resources a flexo facility consumes may lower
the amounts of pollutants, including VOCs and HAPs, released both inside and out-
side the facility.
The flexo ink study assumed that
solvent-based systems would
have oxidizers with a 70%
capture rate and a 95% destruc-
tion efficiency. If a facility has a
higher capture rate (e.g., due to
enclosed doctor blades) or higher
destruction efficiency, expected
emissions would be lower (and
perhaps lower than emissions
from a high-VOC water-based
system).
The energy consumption and cost
estimates assumed a 50% recir-
culation rate for solvent-based
and water-based ink dryers.
An Evaluation of Flexographic Inks on Wide-Web Film
25
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Energy consumed
The solvent-based systems used the most energy to produce the same square footage
of image, because they used energy-consuming oxidizers to destroy hazardous com-
pounds. The water-based systems consumed the least energy, because they used nei-
ther oxidizers nor UV-curing equipment. The energy used by the UV-cured systems
was only slightly higher than that of the water-based inks and was approximately 22%
less than that of solvent-based inks.
Energy-related air emissions
Energy used in flexo both power plants that supply electricity and in some cases at
the flexo facility as well can be a major source of emissions, particularly air emis-
sions. Carbon dioxide (CO2) is released by power generation. Although not regulat-
ed as a pollutant, CO2 is the most common of the "greenhouse gases," which trap
heat in the atmosphere and contribute to global warming. Energy used in flexo
printing also generates hydrocarbons, nitrogen oxides (called NOx and pronounced
"nox"), carbon monoxide (CO), sulfur oxides, and small airborne particles called par-
ticulate matter.
Hydrocarbons (from VOCs), NOx, and CO are smog-forming compounds. Smog is
related to a number of health problems, including eye irritation, headaches, and asth-
ma. In vulnerable people, smog also can aggravate serious lung and heart ailments.
Particulate matter can cause respiratory problems and premature death, as well as
impairing visibility and damaging physical structures such as buildings and sculp-
tures.
For UV-cured ink systems, the releases associated with energy production were
higher than solvent-based systems. The releases from energy production were
lowest for the water-based systems. These differences occurred because all
energy required by the UV systems was derived from electricity a more pol-
lution-intensive energy source than natural gas, whereas much of the energy
used for water-based and solvent-based systems was derived from natural gas,
which releases fewer total pollutants per unit of energy.
26
An Evaluation of Flexographic Inks on Wide-Web Film
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Operating costs
A number of costs are important to facility profitability and have the potential to
highlight differences among ink systems. The study evaluated the costs of materials
(ink and press-side additions), labor, capital, and energy. Substrate costs were not
evaluated because they are not dependent upon ink use. Input quantities for materi-
als were obtained during the performance demonstrations. Suppliers provided infor-
mation about costs.
This analysis averages industry information, and therefore it may not reflect the actu-
al experience of any given printing facility in this short-term demonstration. For
example, the efficiencies of a long run with familiar products were not achieved.
Also, press speed under many printing conditions is expected to be different (and in
general, higher) than in this analysis. While this study focused on those costs that
typically account for the majority of total costs, other important costs (e.g., waste dis-
posal, regulatory compliance, insurance, storage, clean-up, and permitting) should
not be overlooked. In addition, press maintenance and other conditions may affect
ink usage, and therefore ink costs.
Highlights of the cost analysis include the following (Table 7):
Materials were the highest cost category. Water-based inks had the lowest
material costs of the three systems, showing a higher mileage than solvent-
based inks and a much lower per-pound cost than UV-cured inks.
The analysis did not consider start-up and clean-up labor, and the press speed
was assumed to be the same for all three ink systems. (Labor costs might have
differed by ink system if the analysis had captured the costs of preparation,
cleanup, etc.) Therefore, labor cost (wages and benefits for two press opera-
tors) was identical in the study for all three systems.
Energy cost (electricity and natural gas) was highest for UV-cured inks. The
water-based system showed the lowest energy cost because it assumed no
energy use by oxidizers. If oxidizers were to be used, much of the water-based
system's cost advantage would disappear.
Water-based inks had the lowest capital costs (press and other required compo-
nents), because the water-based printers did not use oxidizers. Solvent-based
inks showed higher capital costs because of the expense of oxidizers. Because
TABLE 7 Average Costs of All Systems*
Ink System Materials (Ink &
Press-side Additions)
Solvent-based
Water-based
UV-cured
*Based on running
$15.29
$9.55
$18.63
6,000 square feet and
Labor
$5.29
$5.29
$5.29
500 feet per
Energy
$0.53
$0.35
$1.03
minute.
Capital
$11.87
$11.41
$11.87
Total
$32.98
$26.60
$36.82
An Evaluation of Flexographic Inks on Wide-Web Film
27
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Printers and suppliers need to
work together to evaluate inks,
identify possible alternatives,
compare current and alternative
ink products, and identify cleaner
formulations that meet their per-
formance needs.
UV uses lamps to cure inks, this system also had higher capital costs. However,
the capital costs of a new press for all three technologies were relatively similar.
Therefore, they are likely to be only a small factor in the selection of an ink
system.
Assuming a press speed of 500 feet per minute, total cost was lowest for the
water-based system, with the solvent-based and UV-cured systems costing on
average 24% and 38% more, respectively. The water-based systems did not use
oxidizers, which would have added to the energy and capital costs. Overall
operating costs were highest for UV-cured inks, because materials and energy
were most expensive.
Press speed was found to be critical to overall cost because it influences labor,
capital, and energy costs. Thus, press speed is likely to be the most significant
factor in determining the cost-competitiveness of any ink system.
How to use these findings
The ink systems in the study varied in their risk concerns, performance, emissions,
use of materials and energy, and operational costs. The findings show that there may
not be one best overall choice of an ink system for all conditions and applications,
and that the choice of formulations within an ink system is just as important as the
choice of ink system itself. In calculating their costs, printers should include all
expenses that affect the bottom line, including make-ready and cleanup, waste dis-
posal, storage, permitting and other regulatory requirements, and insurance.
Also, as the study clearly points out, although many individual inks have undergone
technical reformulating in recent years to reduce use of some hazardous substances,
no ink system is inherently free of human health concerns. See Table 2 for suggested
ways to reduce these concerns.
28
An Evaluation of Flexographic Inks on Wide-Web Film
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5
Solvent-based inks: Chemical category findings
Although solvent-based inks typically offer excellent quality and dependability, they
contain relatively high concentrations of VOCs. Oxidizers destroy most stack emis-
sions that would otherwise be released to the environment, but these devices have no
effect on emissions in the pressroom, which may eventually be released to the envi-
ronment. Also, the solvent-based inks in the study contained several chemicals that,
under the conditions of the flexo ink study, were predicted to pose clear risk concerns
for workers. This chapter summarizes the flexo ink study's health-related findings for
the two solvent-based ink product lines.
General population
No chemical categories with clear concern for risk to people living near a printing
facility were identified in the solvent-based systems that were studied, and most cate-
gories presented a negligible concern. The categories of alcohols and propylene glycol
ethers (both used as solvents) contained chemicals that showed potential concern for
risk. Also, the use of press-side additions increased risk concerns for some solvent-
based formulations.
Although the general population was not found to be at clear risk concern, the study
design made specific assumptions resulting in little exposure to people living adjacent
to the facilities. Thus, depending on the conditions at a particular facility, people liv-
ing near a facility could be at risk for health effects if there were sufficient releases.
A chemical category would typi-
cally describe a group of chemi-
cals with shared or similar
chemical and toxicological prop-
erties. The flexo ink study bor-
rowed from EPA's New Chemical
Categories (www.epa.gov/oppt-
intr/newchems/chemcat.htm) as
a means to group the chemical
substances that the partners
shared for this study. To deter-
mine whether other similar sub-
stances would be included in a
chemical category, and therefore
predicted to express similar
health and environmental con-
cerns, category boundary condi-
tions such as molecular structure
and weight, water solubi ity, etc.
should be considered.
Flexo workers
Solvent-based inks had relatively high levels of uncaptured emissions. This is mostly
attributable to solvents, which showed clear risk concerns for pressroom workers
through inhalation. Because of emissions in the pressroom from solvent-based inks,
the study found risk concerns for the following chemical categories:
Alcohols: systemic and developmental risk
Alkyl acetates: systemic risk
Low-molecular-weight hydrocarbons: systemic risk
Propylene glycol ethers: systemic and developmental risk
Table 8 lists the clear inhalation and dermal risk concerns that were found for work-
ers. Alcohols, alkyl acetates, and propylene glycol ethers showed risk concerns for both
dermal and inhalation exposure.
Five of the chemical categories in the study contained solvent-based chemicals that
showed clear concerns via dermal exposure, and three categories showed clear con-
cerns via inhalation. Two categories alcohols and alkyl acetates presented both
dermal and inhalation risk concerns.
This highlights the importance of
minimizing fugitive emissions
through enclosed doctor blades
and other equipment and work-
place practices.
An Evaluation of Flexographic Inks on Wide-Web Film
29
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Chemicals in these categories
were predicted to drive worker
health concerns. When assess-
ing inks at a flexo facility or
developing new formulations,
you might start with these cate-
gories.
TABLE 8 Clear Occupational Health Risk Concerns for
Solvent-Based Inks
Chemical Categories
of Clear Risk Concern'1
Alcohols
Function in Ink Exposure Route**
Solvent
dermal, inhalation
Alkyl acetates
Solvent
dermal, inhalation
Hydrocarbons (low molecular weight)
Multiple
inhalation
Inorganics
Multiple
dermal
Organometallic pigments
Colorant
dermal
Propylene glycol ethers
Solvent
dermal
"These chemical categories might be associated with different risks, or with no risk at all,
under different study conditions. A category is included in the table if at least one chemical in
the category posed a clear risk under the conditions of the study. Not all chemicals in these
categories were found to present risk concerns.
**Only pressroom workers were assumed to have exposure via inhalation. Both prep-room
and pressroom workers were assumed to have dermal exposure.
30
An Evaluation of Flexographic Inks on Wide-Web Film
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6
Water-based inks: Chemical category findings
Four water-based ink product lines were assessed in the flexo ink study. This chapter
addresses the health concerns that were analyzed in the study for the general
population and for flexo workers.
To be considered "water-based," an ink must contain less than 25% VOCs by volume.
However, the range of VOCs in water-based inks can be very large. For example, the
VOC content of the water-based inks in the study ranged from 1% to 14%. Some of
the water-based inks also contained HAPs.
General population
No chemical categories with clear risk concern to people living near a printing facility
were identified in the water-based systems that were studied, and most categories
presented a negligible concern. Alcohols (functioning as solvents) in two water-based
formulations showed potential concern, based on toxicological data. The use of press-
side additions increased concern for some formulations.
The general population was not found to be at clear risk concern, in part because the
study design made specific assumptions that resulted in little anticipated exposure to
people living near facilities. For example, the surrounding population was assumed
to live a minimum of 100 meters distant from the facility. If in actuality people live
closer to a facility than 100 meters, and/or if a facility operates under conditions that
result in substantial VOC emissions, neighbors could be at risk for health effects.
Flexo workers
Table 9 lists the chemical categories in water-based inks that were predicted to pose a
clear risk concern for workers under conditions of the study. Five categories had
chemicals showing clear concerns for health risk via dermal exposure, and three cate-
gories contained chemicals showing clear risks via inhalation. Alcohols, amides or
nitrogenous compounds, and ethylene glycol ethers showed risk concerns for both
dermal and inhalation exposure.
An Evaluation of Flexographic Inks on Wide-Web Film
31
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TABLE 9 Clear Occupational Health Risk Concerns of
Water-based Inks
Chemicals in these categories
were predicted to drive worker
health concerns. When assess-
ing inks at a flexo facility or
developing new formulations,
you might start with these cate-
gories.
Chemical Categories Function in Ink
of Clear Risk Concern*
Alcohols Solvent
Amides or nitrogenous compounds Multiple
Ethylene glycol ethers Solvent
Organic pigments Colorant
Organometallic pigments Colorant
Exposure Route**
dermal, inhalation
dermal, inhalation
dermal, inhalation
dermal
dermal
"These chemical categories might be associated with different risks, or with no risk at all,
under different study conditions. A category is included in the table if at least one chemical
in the category posed a clear risk under the conditions of the study. Not all chemicals in
these categories were found to present risk concerns.
**Only pressroom workers were assumed to have exposure via inhalation. Both prep-room
and pressroom workers were assumed to have dermal exposure.
32
An Evaluation of Flexographic Inks on Wide-Web Film
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UV-cured inks: Chemical category findings
This chapter focuses on health concerns related to the three UV-cured ink product
lines in the flexo ink study.
Only uncured inks only were analyzed in this study, because adequate data about
emissions from inks after curing were not available. Given that most of the volatile
components of UV-cured inks react chemically during curing and are incorporated
into the coating, it is reasonable to expect (but not known for certain) that air emissions
from these inks would be substantially lower in practice.
The use of UV-cured inks in wide-web flexo was a newly developing technology when
the study was designed. Technology advances since that time might result in differ-
ent findings if the study were repeated today.
General population
No chemicals with clear concern to people living near a printing facility were identi-
fied in the UV-cured ink systems that were studied, and most chemicals presented a
negligible concern. Acrylated polyols in one product line (serving as reactive diluents)
contained chemicals of potential risk concern. Certain amides or nitrogenous com-
pounds and acrylated polyols also may present a potential risk.
Flexo workers
Table 10 shows the chemical categories in UV-cured inks that were predicted to pose a
clear risk concern for workers under the conditions of the study. Chemicals in acrylat-
ed polyols (used as UV-curing compounds) were found to pose a clear risk more often
than any other chemical category in UV-cured inks. Acrylated polyols and amides or
nitrogenous compounds showed clear concern for both inhalation and dermal expo-
sure. The other categories (acrylated polymers, organometallic pigments, and
organophosphorus compounds) showed dermal risks only.
Many chemicals used in UV-
cured inks have incomplete toxi-
cology data. More research is
needed to better understand pos-
sible health and environmental
impacts.
An Evaluation of Flexographic Inks on Wide-Web Film
33
-------
Chemicals in these categories
were predicted to drive worker
health concerns. When assess-
ing inks at a flexo facility or
developing new formulations,
you might start with these cate-
gories.
TABLE 10 Clear Occupational Health Risk Concerns for
UV-Cured Inks
Chemical Category
of Clear Risk Concern*
Acrylated polyols
Function in Ink Exposure Route**
UV-curing compounds dermal, inhalation
Acrylated polymers
UV-curing compounds dermal
Amides or nitrogenous
compounds
Multiple
dermal, inhalation
Organometallic pigments
Colorants
dermal
Organophosphorus compounds Multiple
dermal
"These chemical categories might be associated with different risks, or with no risk at all,
under different study conditions. A category is included in the table if at least one chemical
in the category posed a clear risk under the conditions of the study. Not all chemicals in
these categories were found to present risk concerns.
**Only pressroom workers were assumed to have exposure via inhalation. Both prep-room
and pressroom workers were assumed to have dermal exposure.
TSCA Section 5 and Acrylate Esters
A Significant New Use Rule (SNUR) was proposed for acrylate esters, which are found
in some flexographic ink formulations. However, EPA withdrew the proposed SNUR
after receiving, under the terms of a voluntary agreement, toxicity data from acrylate
manufacturers that determined that neither triethylene glycol diacrylate nor triethyl-
ene glycol dimethacrylate were considered carcinogenic. As a result, EPA no longer
supports the carcinogen concern for acrylates as a class. However, EPA may still regu-
late and maintain health concerns for certain acrylates on a "case-by-case" basis when
they are structurally similar to substances for which EPA has supporting toxicity data
or when there are mechanistic/toxicity data supporting the concern. Data from exper-
imental studies show some acrylates can cause carcinogenicity, genotoxicity, neurotox-
icity, reproductive and developmental effects, and respiratory sensitization. For der-
mal exposure, EPA continues to recommend the use of protective equipment, such as
impervious gloves and protective clothing, for workers exposed to new or existing
acrylates and methacrylates. For inhalation exposure, NIOSH-approved respirators or
engineering controls to reduce or eliminate workplace exposures should be used. EPA
continues to evaluate the acrylate chemical category for ecotoxicity
34
An Evaluation of Flexographic Inks on Wide-Web Film
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What workplace safety hazards were found?
Flexo inks and press-side additions may present safety hazards to workers and the
community. To compare the relative safety of ink systems, the inks in the study were
rated for flammability, ignitability, and reactivity.
Findings on workplace safety hazards
As is true for almost every industry, flexo inks may contain chemicals that present
safety hazards in the workplace. Table 11 lists the workplace safety hazards of the inks
in the study.
Because solvent-based inks generally have higher amounts of solvents, they
posed workplace hazards for both flammability and ignitability. They had an
average flammability rank of 3, which means they can easily be ignited under
almost all normal temperature conditions. They also were rated as ignitable
(can be ignited under 140°F). None were reactive.
The water-based inks, which contained varying percentages of flammable sol-
vents, were less flammable on average than solvent-based inks. However, the
range was wider, and some water-based ink formulations were as flammable as
solvent-based formulations. No water-based inks were ignitable or reactive.
Reactivity and flammability data were only available for one of the UV-cured
inks, which was rated as slightly flammable and slightly reactive. None of the
UV-cured inks were ignitable.
How to use these findings
The safety of inks in the study varied by ink system, and water-based inks showed an
especially wide range of flammability rankings. It is therefore not appropriate to
assume that an ink necessarily shares the common characteristics associated with
TABLE 11 Workplace Safety Hazards of the Flexo Inks
Flammability Ignitability Reactivity
(ranked 0-4)* (yes/no) (ranked 0-4)*
Range across
Range across
Range across
solvent-based inks
water-based inks
UV-cured inks
* A rank of 0 indicates a very safe product,
product.
3 yes 0
0-3 no 0
1 no 1
whereas a rank of 4 indicates a highly unsafe
An Evaluation of Flexographic Inks on Wide-Web Film
35
-------
Water-based inks showed an
especially wide range of flamma-
bility rankings.
other inks in the same system. It is important to check the safety rankings for all inks
used and stored in the facility.
Also, following systematic procedures for safely preparing, operating, and cleaning
press equipment will help to avoid serious injuries and health problems to employees.
An effective process safety program identifies workplace hazards and seeks to elimi-
nate or reduce their potential for harm. As part of any safety program, printers should
follow all safety guidelines and rules,
clearly post all relevant MSDSs,
become aware of the safety hazards for all chemicals used and stored in the
facility,
have emergency evacuation and notification procedures in place, and
consider whether ink products with lower safety ratings are available and
suitable.
36
An Evaluation of Flexographic Inks on Wide-Web Film
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9
What aquatic toxicity concerns were identified?
A chemical with aquatic toxicity concerns has the potential to cause harmful long-
term effects to aquatic life. This chapter identifies the chemicals that showed medium
or high aquatic toxicity in the study.
Findings on aquatic toxicity
For the flexo study, if 0.1 mg of a chemical in one liter of water could cause a problem
for aquatic organisms, the chemical was said to have high aquatic toxicity. Similarly, if
more than 0.1 mg/liter and up to 10 mg/liter would be needed to cause a problem, a
flexo ink chemical was said to have medium aquatic toxicity.
Each ink system contained chemicals of high aquatic toxicity:
Solvent-based system: 11 chemicals
Water-based system: 8 chemicals
UV-cured system: 12 chemicals
About half of the ink chemicals in the study showed medium or high aquatic toxicity.
Eighteen chemicals had high aquatic toxicity, and another 35 chemicals showed medi-
um toxicity. Table 12 lists these chemicals.
An Evaluation of Flexographic Inks on Wide-Web Film
37
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TABLE 12 Flexo Ink Study Chemicals Showing Aquatic Toxicity
It is important to store and use
chemicals properly, to avoid acci-
dental releases that may end up
in water systems. Inks and their
wastes should never be put down
the drain.
High aquatic toxicity
Amides, tallow, hydrogenated
Ammonia*
C.I. Basic Violet 1,
molybdatephosphate
C.I. Basic Violet 1,
molybdatetungstatephosphate
C.I. Pigment Violet 27
Dicyclohexyl phfha/afe*
Distillates (petroleum), hydrotreated
light
2-Ethylhexyl dipheny/ phosphate*
Glycerol propoxylate triacrylate
n-Hepfane*
1,6-Hexanediol diacrylate
2-lsopropylthioxanthone
4-lsopropylthioxanthone
Mineral oil*
Resin acids, hydrogenated, methyl
esters
Sfyrene*
Thioxanthone derivative
Trimethylolpropane ethoxylate
triacrylate
Medium aquatic toxicity
Acrylic acid polymer, acidic #1
Acrylic acid polymer, acidic #2
Alcohols, Cl 1 -1 5-secondary,
ethoxylated
Ammonium hydroxide*
2-Benzyl-2-(dimethylamino)-4'-
morpholinobutyrophenone
Butyl acetate*
C.I. Pigment Blue 61
C.I. Pigment Red 48, barium salt (1:1)
C.I. Pigment Red 48, calcium salt (1:1)
C.I. Pigment Red 52, calcium salt (1:1)
Citric acid
D&C Red No.7
Dioctyl sulfosuccinate, sodium salt
Dipheny I (2,4,6-trimethylbenzoyl)
phosphine oxide
Dipropylene glycol diacrylate
Efhano/ami'ne*
Ethyl acetate*
Ethyl 4-dimethylaminobenzoate
1 -Hydroxycyclohexyl phenyl ketone
Hydroxylamine derivative
Hydroxypropyl aery late*
Isopropoxyethoxytitanium
bis(acetylacetonate)
Methylenedisalicylic acid
2-Methyl-4'(methylthio)-2-
morpholinopropiophenone
Phosphine oxide, bis(2,6-
dimethoxybenzoyl) (2,4,4-
trimethylpentyl)-
Propyl acetate*
Resin, acrylic
Solvent naphtha (petroleum), light
aliphatic
Styrene acrylic acid polymer #1
Styrene acrylic acid polymer #2
Styrene acrylic acid resin
Tetramethyldecyndiol
Titanium diisopropoxide bis (2,4-
pentanedionate)
Trimethylolpropane propoxylate
triacrylate
Trimethylolpropane triacrylate
*Regulated under one or more federal environmental/health statutes.
Because it was not expected that the inks or their wastes would be released to the
aquatic environment, water releases and subsequent related risks were not assessed.
If any of these inks are ever released untreated to water, however, there could be
aquatic risk concern. In fact, four of the chemicals listed in Table 12 ammonia,
butyl acetate, dicyclohexyl phthalate, and styrene have been regulated under the
Clean Water Act.
38
An Evaluation of Flexographic Inks on Wide-Web Film
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As Table 12 shows, only about 20% (11/53) of these chemicals are regulated by feder-
al laws that protect the environment. Thus, even though the other chemicals in the
table were found to exhibit high aquatic toxicity, no specific restrictions exist on
their use.
How to use these findings
About half the chemicals in the flexo ink study were identified as having high or
medium toxicity to the aquatic environment. Toxic chemicals were found in every
ink system, and the majority of them are not federally regulated. Ink chemicals and
wastewater containing ink products can be accidentally spilled or released to the
environment. For these reasons, it is up to flexo professionals to take the initiative.
To help reduce exposure, and consequently risk, to aquatic environments:
Never pour inks or ink-related products (such as press-side additions or wash
water) down the drain.
Minimize the use of chemicals that have been found to be toxic to the envi-
ronment.
Keep in mind that some unregulated chemicals may still pose hazards to the
environment.
Consider and use alternatives to toxic ink chemicals when available.
Support research to identify environmentally benign inks and ink chemicals.
An Evaluation of Flexographic Inks on Wide-Web Film
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ADDITIONAL
INFORMATION
Inks in the study
The ink systems
The study examined the three main flexo ink systems: solvent-based, water-based,
and UV-cured. To investigate whether any one ink system showed clear advantages
in terms of health, safety, or environmental aspects, the study compared the three
ink systems and looked at the chemicals and chemical categories in the individual
inks.
The primary difference among the ink systems is the method used for drying or cur-
ing the ink. Solvent-based and water-based inks are dried by evaporation, whereas
UV-cured inks are cured by chemical reactions. Flexo inks contain components that
are responsible for several main functions, including solvents, colorants, resins, addi-
tives, and (for ultraviolet inks only) UV-curing compounds.
Solvent-based inks
Solvent-based inks are generally considered the industry standard for ease of use and
quality of printing, and they are widely used in flexo. However, because these inks
dry by evaporation, the solvents usually contain significant amounts of VOCs, which
have notable health and safety concerns. VOCs are usually very flammable, and they
contribute to the formation of ground-level ozone (a component of smog), which
causes respiratory and other health problems. Solvent-based ink systems are
equipped with oxidizers and other pollution-control devices to destroy VOCs.
Water-based inks
Although the primary solvent in water-based inks is water, these inks can and usually
do contain VOCs, up to a maximum of 25% by volume. They may also contain one
or more of the 188 hazardous air pollutants that were listed in the 1990 Clean Air
Act. Depending on their HAP and VOC content, water-based inks may or may not
have fewer health and environmental concerns than traditional solvent-based inks.
(Note that in some locations and for some water-based inks, oxidizers must be used
to destroy VOCs and most HAPs.) Also, again depending on their VOC content,
water-based inks show a range of flammability. Some of them are not at all flamma-
ble, but others are as flammable as some solvent-based inks.
UV-cured inks
UV-cured inks are the newest ink system to make major progress in flexo. The use of
UV inks has been steadily increasing, especially for narrow-web labels and tags.
Chemicals in UV-cured inks form solids and bond to the substrate when they are
exposed to ultraviolet light, whereas solvent-based and water-based inks dry by evap-
oration. Because of this difference, UV-cured inks do not contain traditional solvents,
40
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so they may have very low VOC content. However, they do contain many chemicals
that have not been tested comprehensively for environmental, health, and safety
impacts.
Functional components of flexo ink chemicals
Chemical components allow ink to adhere to a substrate. These components can be
divided into five basic functional categories:
Solvents
Colorants
Resins
Additives
UV-curing compounds
Some chemical categories are called "multi-functional." A category with this label
contains multiple chemicals that serve different functions. Thus chemical A might
be a solvent and chemical B an additive. Each chemical was assigned to only one
functional category.
Solvents help deliver the ink to the substrate. The solvent allows the ink to flow
through the printing mechanism, and then the solvent evaporates so that the ink
forms a solid coating on the substrate. Typically, inks are manufactured and trans-
ported in a concentrated form, and the printer must add solvent to the ink to attain
the desired viscosity (flow). A solvent must adequately disperse or dissolve the solid
components of the ink, but it must not react with the ink or with any part of the
press. It must dry quickly and thoroughly, and have little odor.
Colorants give inks their color. The two types of colorants used in printing are dyes
and pigments. Dyes can be useful when transparency is desired, and the colors of
dyes are often quite strong. However, dyes can be susceptible to attack by chemicals
and water, and they can also be toxic. Pigments are small, insoluble particles. Some
pigments can also be toxic. In general, pigment-containing inks are more resistant to
chemicals and heat and are less prone to bleeding through the substrate than are
dye-containing inks. The inks used in this study contained pigments, including
those that are based on organic, inorganic, and organometallic structures.
Resins cause ink to stick to the substrate. They also disperse the pigment and give
gloss to the finished coating. Resins can provide flexibility, scuff resistance, cohesive
strength, block resistance, and compatibility with printing plates. Common cate-
gories of resins include nitrocellulose, polyamides, carboxylated acrylics, and polyke-
tones.
Additives are used to improve the performance of inks. Plasticizers enhance the flex-
ibility of resins. Waxes and other slip additives provide lubrication to the dried ink
and resist damage from rubbing and scuffing. Wetting agents modify the surface ten-
sion to help inks stick to the substrate. Defoaming agents reduce bubble-forming
An Evaluation of Flexographic Inks on Wide-Web Film
41
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tendencies of water-based inks. Buffers maintain the pH of the ink at a desired level.
Inhibitors are used to prevent an unwanted chemical change.
UV curing compounds enable UV inks to chemically change to dry solids that bond
with the substrate. Monomers are individual molecular units that can combine to
form larger structures known as polymers. Acrylated polyols act as monomers, where-
as acrylated polymers can be both monomers and polymers. Oligomers are small
polymers that can be further combined to form larger polymers. Photoinitiators,
such as aromatic ketones, aromatic esters, and organophosphorous compounds, use
UV light to enable a chemical reaction to take place among monomers and
oligomers.
Every function is associated with specific categories of chemicals, which are listed in
Table 13.
TABLE 13 Chemical Categories by Ink Function
Solvents Colorants Resins Additives Curing Multiple Functions
Compounds
Solvent-based system
Alcohols
Alkyl
acetates
Propylene
glycol
ethers
Organic,
inorganic, and
organometallic
pigments
Polyol
derivatives
Resins
High -molecular-weight
hydrocarbons
Organic acids or salts
Olefin polymers
(waxes)
Organotitanium
compounds
(adhesion promoters)
Siloxanes (defoamers
and wetting agents)
None
Amides or nitrogenous
compounds (slip
additives, buffers,
inhibitors)
Inorganics
Low-molecular-weight
hydrocarbons
Water-based system
Alcohols
Ethylene
glycol
ethers
Propylene
glycol
ethers
Organic,
inorganic, and
organometallic
pigments
Resins
Acrylic acid polymers
High -molecular-weight
hydrocarbons
Organic acids or salts
Siloxanes (defoamers
and wetting agents)
None
Amides or nitrogenous
compounds (slip
additives, buffers,
inhibitors)
Inorganics
Low-molecular-weight
hydrocarbons
UV-cured system
Alcohols
Organic,
inorganic, and
organometallic
pigments
Polyol
derivatives
Resins
Aromatic esters
(plasticizers)
Olefin polymers
(waxes)
Siloxanes (defoamers
and wetting agents)
Acrylated polyols
Acrylated
polymers
Aromatic esters
Aromatic ketones
Organophos-
phorous
compounds
Amides or nitrogenous
compounds (slip
additives, buffers,
inhibitors)
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Methodology of the flexo ink study
The study used a methodology called a Cleaner Technologies Substitutes Assessment
(Figure 1). A CTSA systematically evaluates traditional and alternative technologies
for the potential risks they pose to human health and the environment, as well as for
performance and cost. The objective of this CTSA (the flexo ink study) was to devel-
op a comprehensive and systematic picture of the three primary flexo ink technolo-
gies.
When the study was conducted,
UV-cured inks were not being not
used commercially to a signifi-
cant extent to print film substrates
on wide-web presses.
Inputs
9 Ink Product Lines
(each with 5 colors)*
2 solvent-based
4 water-based
3 UV-cured
3 Film Substrates**
OPP
LDPE
PE/EVA
FIGURE 1 Study Methodology
Data Collection
Analyses
Performance
Demonstrations
Laboratory Runs
Supplier and
Printer Data
w
Emissions
Risk
Energy Use
Cost
Performance
Results
CTSA document
* blue, white, cyan, magenta, green.
** OPP = oriented polypropylene. LDPE = low-density polyethylene.
PE/EVA = polyethylene/ethyl vinyl acetate co-extruded film.
The study printed samples using nine ink product lines, each containing five colors
(blue, white, cyan, magenta, and green). Altogether, the 45 ink formulations con-
tained more than 100 chemicals. Printing ink suppliers voluntarily provided the ink
formulations, which represented the three primary flexo ink systems in use at the
time: solvent-based, water-based, and UV-cured. The inks fell into the following cate-
gories:
two solvent-based product lines,
four water-based product lines, and
three UV-cured product lines.
This study was not designed to cover every possible ink formulation, performance
category, or substrate type. Rather, it gives a "snapshot" of flexo inks at a specific
point in time. This is important, because although this booklet identifies issues to
consider when thinking about the "best" inks for workers and the environment, each
facility and job is unique, and these results should not be generalized. This booklet
can help flexo professionals learn more about integrating risk, performance, and cost
considerations to both improve operations and reduce environmental impacts.
An Evaluation of Flexographic Inks on Wide-Web Film
43
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The general CTSA methodology
is described in the DfE docu-
ment, Cleaner Technologies
Substitutes Assessment: A
Methodology and Resources
Guide. The complete
Flexographic Ink Options: A
Cleaner Technologies Substitutes
Assessment (CTSA) describes the
methodology used for this study.
You may download these docu-
ments from the DfE website
(www.epa.aov/dfel.
Performance
The partners included in the study a series of performance demonstrations brief
printing runs of a representative 20" x 16" test image (Figure 2) printed using wide-
web presses onto three types of film substrates. Through Flexo Project partners,
eleven commercial wide-web printing facilities volunteered as sites for the perform-
ance demonstrations. Test samples were printed using a representative image that
enabled analysis of 18 performance tests that were considered important to flexo
printers. Some tests were conducted during the demonstrations runs, and afterwards
the printed images were sent to Western Michigan University, where other perform-
ance tests were conducted.
FIGURE 2 Test Image Used in Demonstration Runs
(original was run in 5 colors)
Hazards and risks
To analyze the hazards, exposures, and risk concerns of chemicals in the inks, the
study used published toxicological data, EPA release and exposure models, and EPA
structure-activity analyses. The release and exposure models helped to determine the
rate at which flexo workers are exposed to ingredients in inks. The study analyzed two
routes or pathways by which flexo workers could be exposed to ink chemicals: inhala-
tion (breathing), and dermal (skin). The amount of exposure a worker receives can
be affected by chemical components of the inks, methods of handling inks, and expo-
sure route.
44
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The structure-activity analyses provided hazard information for chemicals that had
not been subjected to toxicological research. Because many ink chemicals have not
undergone research about their health and environmental effects, SAT reports were
used for many of the flexo chemicals in the study. Figure 3 shows graphically the
process that the study used to develop the risk assessment for flexo ink chemicals.
FIGURE 3 The Risk Assessment Process Used in the Flexo Ink Study
Workplace
Practices
Source
Release
Assessment
Exposure
Assessment
Human
Health
Hazards
Risk
Characterization
Environmental
Hazards
Hazard
Assessment
Operating costs
The study looked at the costs of buying and using inks that were submitted voluntari-
ly by printing ink suppliers. Sources of information about ink costs included members
of the Flexo Partnership Technical and Steering Committees, contributors to the per-
formance demonstrations, and U.S. Census data. Cost categories that were analyzed
in the study include materials, labor, capital, and energy. The cost of substrates was
not included in the analysis, because the amount of substrate used did not depend
on the ink system.
Energy and natural resources
The study looked at the electricity and natural gas that were consumed in printing
these inks. Sources of information about the consumption of ink products included
Members of the Flexo Partnership Technical and Steering Committees
Contributors to the performance demonstrations
Energy equipment vendors
U.S. Department of Energy data
An Evaluation of Flexographic Inks on Wide-Web Film
45
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The study also looked at the types and amount of emissions that might be generated
by printing with each ink system.
Research assumptions
The study looked at many aspects of printing flexo inks, and thus was complex to
plan and implement. In any study design, assumptions are made that will influence
the results. For the flexo ink study, some of the important assumptions include the
following.
At each volunteer test site, the test image was run at a press speed of 300-500
feet per minute for roughly two hours. Press speed under many printing condi-
tions is expected to be different (and in general, higher) than in this analysis.
When the project methodology was developed, regulations did not require that
air pollution control equipment be used with low-VOC inks. Therefore, the
energy and cost calculations assumed that an oxidizer was used with solvent-
based inks but not with water-based or UV-cured inks.
Workers could be exposed to chemicals via dermal (skin) or inhalation (breath-
ing) absorption, and the general population could be exposed via inhalation
only. Neither population was subject to toxic effects via oral exposure (e.g.,
drinking or eating contaminated substances).
A "model facility" was designed to use when calculating the risk, cost, and energy
consumption figures. A number of assumptions were made about a hypothetical
"model facility" in developing the risk assessment. Thus, facilities with different
operating characteristics would have different findings.
Thirty percent of VOCs released to air would be uncaptured emissions, and 70%
would be stack emissions.
Solvent-based ink systems would have a catalytic oxidizer with a 95% destruc-
tion efficiency.
Pressroom and prep-room workers would work a 7.5 hour shift, 250 days/year.
Pressroom and prep-room workers would have routine two-hand contact (no
gloves) with ink unless a substance was corrosive.
Press speed would be 500 feet per minute.
These parameters are important to keep in mind when considering how the results
may apply to an actual printing facility.
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Environmental resources
The resources listed here are divided into four sections: selected publications, flexo
associations, technical assistance organizations, and chemical information sources.
Many of these publications can be found on the DfE website (www.epa.gov/dfe).
which may also serve as a source of information on other chemical substances. The
DfE Program has reviewed many chemical substances in other cleaner technology
evaluations, including previous partnerships focused on the activities of screen and
lithographic printers.
DfE documents may also be obtained from:
National Service Center for Environmental Publications
PO. Box 42419
Cincinnati, OH 45242-2419
Phone: 800-490-9198 or 513-489-8190
Fax:513-489-8695
e-mail: nceipmal@one.net
Internet: www.epa.gov/ncepihom/ordering.htm
Selected publications
Flexographic Ink Options: A Cleaner Technologies Substitutes Assessment
(EPA 744-R-02-001A&B)
Vol. A 400 pages; Vol. B (Appendices) 430 pages; February 2002
The CTSA contains detailed information about the study. It includes chapters on risk
analysis, 18 performance tests, cost analysis, energy consumption, a benefit-cost
analysis, and environmental impacts.
Inside Flexo: A Cleaner Run for the Money (EPA/744-V-98-001)
19 minutes; April 1998
This video provides useful tips to flexo printers for working more efficiently and sav-
ing money, while improving the environment. Veteran printers share their success sto-
ries in the following areas: (1) managing inks efficiently, (2) printing successfully with
alternative inks, (3) making the best use of press return inks, (4) using new cleaning
methods that improve efficiency, and (5) improving the bottom line through sound
environmental practices.
Flexography Project Case Study #1: Reducing VOCs in Flexography
(EPA/744-F-96-013)
4 pages; March 1997
Highlights the experiences of a flexography printer who successfully reduced VOC
emissions and hazardous waste volumes. The case study focuses on the use of water-
based ink and cleaning systems, which reduced costs along with environmental and
worker-safety concerns. Tambien disponible en espanol.
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Flexography Project Case Study #2: Learning from Three Companies that Reduced
VOC Emissions (EPA/744-F-96-016)
4 pages; June 1997
Highlights how three flexo printing facilities went about reducing their VOC emis-
sions. It presents the factors that went into management decisions, the results of
switching to water-based inks and of installing an oxidizer, and how ink suppliers,
trade associations, and consultants can help printers make decisions and solve prob-
lems. Tambien disponible en espanol.
High Performance Flexo: Printing with a Cleaner, Greener Image (Videoconference)
2.5 hours; 2000
This tape includes the entire videoconference, which discussed ways to improve envi-
ronmental aspects of flexo printing. It is available through the Printers National
Environmental Assistance Center (PNEAC) at www.pneac.org.
Printing Industry and Use Cluster Profile (EPA/744-R-94-003)
183 pages; June 1994
This resource provides an in-depth profile of the U.S. printing industry. Demographic
information is given for the entire industry, as well as for the specific sectors: screen
printing, lithography, gravure, flexography, and letterpress. The profile also presents
detailed information about the processes and technological trends involved in each
sector.
Integrated Environmental Management Systems Implementation Guide
(EPA744-R-00-011)
290 pages, 48 worksheets; October 2000
The Guide was developed over three years and has been tested by several small busi-
nesses that used it to build an Integrated Environmental Management System
(EMS) for their companies. An IEMS integrates worker safety and health concerns
along with environmental concerns into a company's cost and performance analysis
of products, processes and activities. An IEMS also includes the principles and tech-
nical methods of the EPA's Design for the Environment (DfE) Program, which
emphasizes reducing risk to humans and the environment, along with preventing pol-
lution and managing resources wisely. The Guide provides clear, step-by-step guid-
ance on implementing an IEMS in a small company.
Integrated Environmental Management Systems Company Manual Template for Small
Business (EPA 744-R-00-012)
60 pages; December 2000
The template was developed to help companies document their IEMS. Written as if
it were the actual manual of a specific small business, the template helps companies
understand how to adapt the procedures to implement an EMS and how to docu-
ment their IEMS. It contains procedures that are normally documented as part of an
ISO 14001-compliant EMS.
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Flexographic associations
The following organizations are partners in the DfE Flexography Project:
California Film Extruders and Converters Association
www.cfeca.org
The California Film Extruders and Converters Association (CFECA) is a trade asso-
ciation of manufacturers and suppliers dedicated to representing the broad interests
of the plastic film extruding and converting industry in California.
Film and Bag Federation
www.plasticbag.com
The Film and Bag Federation of The Society of the Plastics Industry is a consortium
of 60 of the industry's leading manufacturers and suppliers, who work together on
issues of interest and concern to the industry. Among its goals are to promote the
industry's growth and to provide members with programs, services and the forum for
addressing environmental, regulatory and other industry issues.
Flexible Packaging Association
www.flexpack.org
The Flexible Packaging Association (FPA) is the leading trade association for convert-
ers and suppliers of flexible materials and allied products for packaging, industrial,
and related end-use markets. FPA represents their interests before government, pro-
motes the value of their products, and provides information related to their indus-
tries.
Flexographic Technical Association
www.flexography.org
The Flexographic Technical Association is the leading technical society devoted
exclusively to the flexo printing industry. Its members come from all aspects of the
flexo industry, and include printers, suppliers, graphic trade shops, consumer product
companies, designers, end-users, consultants, and educational institutions. Together
they provide a wealth of products, services and shared knowledge to the flexographic
printing industry.
National Association of Printing Ink Manufacturers
www.napim.org
The National Association of Printing Ink Manufacturers is a trade association that
provides information and assistance to its members, to help them better manage
their businesses, and that represents the printing ink industry in the United States.
RadTech International North America
www.radtech.org
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RadTech International North America, a non-profit organization, is the association
for the advancement of ultraviolet and electron beam (UV/EB) technology. RadTech
serves as an industry forum, addressing the educational needs of the users and suppli-
ers of UV and EB equipment and materials.
Environmental technical assistance organizations
Several non-profit and government sources of technical assistance and pollution pre-
vention information are listed below.
EPA Small Business Ombudsman
www.epa.gov/sbo/
The Office of the Small Business Ombudsman (EPA SBO) serves as an effective con-
duit for small businesses to access EPA and facilitates communications between the
small business community and the Agency. It also provides a list of state SBOs with
expertise on local issues. The EPA SBO reviews and resolves disputes with EPA and
works with EPA personnel to increase their understanding of small businesses in the
development and enforcement of environmental regulations. The EPA SBO acts as a
liaison for the small business community in the development of EPA regulations and
standards.
EPA Regional Pollution Prevention Coordinators
http://www.epa.gov/opptintr/p2home/resources/regions.htm
Each region of the United States has a coordinator for pollution prevention (P2)
activities. This website lists the contacts and provides a link to a webpage describing
activities in each region.
National Pollution Prevention Roundtable
www.p2.org
The National Pollution Prevention Roundtable (NPPR) is the largest membership
organization in the United States devoted solely to pollution prevention (P2). The
mission of the Roundtable is to provide a national forum for promoting the develop-
ment, implementation, and evaluation of efforts to avoid, eliminate, or reduce pollu-
tion at the source. NPPR holds national meetings; runs its publications program,
which includes its quarterly newsletter and many other documents and reports; oper-
ates four topic-specific electronic listservs (NPPR [P2 Policy], P2 Tech, P2 Trainer,
and P2 Energy); and coordinates roundtable workgroups.
Printers National Environmental Assistance Center (PNEAC)
www.pneac.org
EPA's Office of Enforcement and Compliance Assurance and Pollution Prevention
Policy Staff have partnered with industry and environmental experts to develop this
environmental assistance center for the printing industry, including compliance assis-
tance and P2 information.
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This is a communications-based center linking trade, governmental, and university
service providers to efficiently provide the most current and complete compliance
assistance and pollution prevention information to the printing industry. The pro-
ject's staff are located within the partnering organizations. The Great Lakes
Information Network is providing support for the two Internet listservs.
Small Business Assistance Program
www.epa.gov/ttn/sbap/
All states have a small business assistance program to help businesses comply with
environmental regulations. The EPA Small Business Assistance Program (SBAP) is a
forum for state assistance providers to share information, and it provides a list of
state SBAPs with expertise on local issues. The SBAP has a website and several publi-
cations that provide information to small businesses, as well as contact information
for individual state representatives.
Small Business Development Centers
www.sba.gov/sbdc/
The U.S Small Business Administration (SBA) administers the Small Business
Development Center Program to provide management assistance to current and
prospective small business owners. SBDCs offer one-stop assistance to small busi-
nesses by providing a wide variety of information and guidance in central and easily
accessible branch locations. The lead organization coordinates program services
offered to small businesses through a network of subcenters and satellite locations in
each state.
The program is a cooperative effort of the private sector, the educational community,
and federal, state, and local governments. The program is designed to deliver up-to-
date counseling, training, and technical assistance in all aspects of small business
management. SBDC services include, but are not limited to, assisting small business-
es with financial, marketing, production, organization, engineering, and technical
problems and feasibility studies. The website provides contact information for local
representatives.
Manufacturing Extension Partnership (MEP)
www.mep.nist.gov
MEP is a nationwide network of not-for-profit centers in more than 400 locations
nationwide, whose sole purpose is to help small and medium-sized manufacturers.
The MEP centers, serving all 50 states, the District of Columbia and Puerto Rico, are
linked through the Department of Commerce's National Institute of Standards and
Technology. With specialists who have experience on manufacturing floors and plant
operations, MEPs can perform assessments, provide technical and business solutions,
help create successful partnerships, and provide seminars and training programs.
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Chemical information
Following are some sources of chemical information to help you better build chemical
profiles on flexographic ink ingredients and better understand the health and environ-
mental impacts of flexo inks.
ASTDR (Agency for Toxic Substances and Disease Registry).
http://atsdrl .atsdr.cdc.gov
ToxFAQs. A series of summaries about hazardous substances from the ATSDR
Toxicological Profiles and Public Health Statements. Each fact sheet serves as a
quick and easy-to-understand guide to the effects of hazardous substances on
human health.
http://www.atsdr.cdc.gov/toxfaq.html
Toxicological Profiles. Toxicological profiles for hazardous substances found at
National Priorities List sites. Profiles include minimum risk levels.
http://www.atsdr.cdc.gov/toxpro2.html
ChemlD. The National Library of Medicine's Chemical Dictionary. Contains over
339,000 compounds of biomedical and regulatory interest. Records include CAS Registry
Numbers, molecular formulae, generic names, synonyms, and other references.
http://chem.sis.nlm.nih.gov/chemidplus
ChemFinder. Searchable database of chemical names, synonyms, CAS Registry Numbers,
and molecular formulas.
http://chemfinder.camsoft.com
Chemical Right-to-Know (RTK) Initiative, U.S. EPA. Developed to rapidly test chemicals
and make the data available to scientists, policy makers, industry, and the public.
http://www.epa.gov/chemrtk
ECOSAR (Ecotoxicity of Structure-Activity Relationships Database). Based on structure
analysis, contains estimates of toxicity to fish, invertebrates, and aquatic plants.
http://www.epa.gov/oppt/newchems/21 ecosar.htm
ECOTOX Database System. Chemical-specific ecological toxicity databases. Includes
AQUIRE, for aquatic toxicity.
http://www.epa.gov/ecotox
International Agency for Research on Cancer (IARC). Overall evaluations of carcino-
genicity to humans. List and searchable database of chemicals evaluated as IARC
Monographs.
http://193.51.164.ll
National Toxicology Program (NTP) Annual Report on Carcinogens. This contains lists
of chemicals known or reasonably anticipated to be carcinogenic to humans.
http://ntp-server.niehs.nih.gov/NewHomeRoc/CurrentLists.html
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Office of Pollution Prevention and Toxics (OPPT), U.S. Environmental Protection
Agency. Databases and software produced by OPPT are valuable tools for obtaining chem-
ical and regulatory information.
http://www.epa.gov/opptintr/opptdb.htm
EPA's Exposure Assessment webpage includes exposure assessment methods, data-
bases, and prediction models.
http://www.epa.gov/opptintr/exposure
Estimation Program Interface (EPI) Suite is a series of physical/chemical property
and environmental fate estimation models.
http://www.epa.gov/opptintr/exposure/docs/episuite.htm
http://www.epa.gov/opptintr/exposure/docs/epiwin.htm
Flexography Project website contains many documents to help flexo professionals
develop market environmentally improved ink formulations.
h ttp: //www. e p a. g ov/df e
RTECs (Registry of Toxic Effects of Chemical Substances). Toxicity data for over
140,000 chemicals. Only available through commercial vendors; URL provides further
vendors.
http://www.cdc.gov/niosh/rtecs.html
TOXNET The National Library of Medicine's Toxicology Data Network. Contains data-
bases on toxicology, hazardous chemicals, and related areas.
http://toxnet.nlm.nih.gov
Toxnet includes:
CCRIS (Chemical Carcinogenisis Research Information System). Sponsored by the
National Cancer Institute, a scientifically evaluated and fully referenced data bank
containing some 8,000 chemical records with carcinogenicity, mutagenicity, tumor
promotion, and tumor inhibition test results.
GENE-TOX. Genetic toxicology (mutagenicity) test data, resulting from expert
peer review of the open scientific literature for approximately 3,000 chemical sub-
stances.
HSDB (Hazardous Substances Data Bank). Data file that focuses on the toxicology
of over 4,500 potentially hazardous substances. Includes human exposure, industrial
hygiene, emergency handling, and environmental fate. Scientifically peer-reviewed.
IRIS (Integrated Risk Information System). An EPA database that contains health
risk information on over 500 chemicals. This includes cancer weight-of-evidence
classifications and cancer potency factors. These data have been reviewed by EPA
and represent EPA consensus.
http://www.epa.gov/iris
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Pollution prevention tips for flexo professionals
Flexo decision-makers have many opportunities to encourage environmental
improvements and cleaner, more sustainable operations, including pollution preven-
tion. This involves reducing or eliminating environmental discharges at the source,
before they are generated. Pollution prevention requires taking active steps to imple-
ment changes in workplace practices, technology, and materials, such as the type of
ink used. By reducing the amount of waste produced in the first place, disposal and
compliance issues are minimized.
Source Reduction
k Recycling
Treatment
Disposal .
The pollution prevention pyramid shows
source reduction at the top. This means that
reducing or eliminating environmental prob-
lems should be the first and most compre-
hensive approach to preventing pollution. If a
chemical showing hazards or risk concerns
cannot be eliminated, then it should be recy-
cled. If it cannot be recycled as is, it should
be treated, and only if none of these options
exist should it be disposed to a landfill.
Each step in the printing process offers opportunities for pollution prevention.
Possible benefits from following pollution prevention practices include cost savings,
improved productivity, better product quality, reduced health risk concerns to work-
ers, reduced pressures of regulatory compliance, and of course reduced environmental
impacts.
The list that follows includes some obvious and some not-so-obvious suggestions for
reducing environmental effects of printing operations. You can probably implement
other good ideas that are specific to your facility's operations.
Pre-press
Use Computers for Proofs and Plates: Eliminating all proofs and plates enables print-
ers to skip photographic development and eliminate the use of darkroom chemicals.
Switch from Rubber to Photopolymer Plates: Use of traditional nitric acid baths to
etch designs into metal plates may generate wastewater that is low in pH and high in
metal content, requiring regulation under the Clean Water Act. Photopolymer plates
eliminate this waste stream as well as the metal engravings and wastes generated
from the production of conventional molded rubber plates.
Printing and clean-up
Install Enclosed Doctor Blade Chambers: Enclosed doctor blade chambers reduce ink
evaporation, which results in better control of ink usage, more consistent color, and
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improved performance of the inks on press. Making this change to an older press
may greatly reduce ink evaporation, thus minimizing worker exposure to hazardous
chemicals.
Cover Volatile Materials: By keeping all cans, drums, and open ink fountains covered,
printers can reduce odors and worker health risk concerns by minimizing uncaptured
VOC emissions.
Use Higher Linecount Anilox Rolls: This enables printers to apply smaller ink
droplets closer together, to achieve much finer ink distribution, easier drying, and
potentially faster press speeds.
Rework Press Return Ink: Reworking press return ink can increase efficiency, reduce
ink purchases, and reduce hazardous waste if contamination issues can be addressed.
Ink can be reworked by blending press return ink with virgin ink or other press return
inks.
Use Computerized Ink Blending: Software and specialized equipment help printers
blend ink, reduce surplus ink, and reuse press return ink.
Print with Four-Color Process: The limited number of inks in four-color process print-
ing can minimize the amount of mixed colored inks used and eliminate residues of
unusual colors at the end of each job. With chambered doctor blade systems, the
increased use of process printing to produce a broad spectrum of colors has become
more easily attainable.
Co-Extrude Colored Film: Films can be co-extruded to have panels of color in a clear
field, which eliminates the need for heavy coverage with colored ink.
Run Light Colors First: By running lighter jobs before darker jobs, printers can reduce
the number of clean-ups.
Standardize Repeat Print Jobs: Make-ready times and waste materials can be greatly
reduced if the press operators knows the anilox roll linecount and cell volume, the
sequence of colors applied, ink parameters such as pH and viscosity, and other set-up
information.
Standardize Anilox Roll Inventory: This saves time during makeready and reduces
waste.
Use Multi-Stage Cleaning: Solvent use can be reduced by using a multi-stage clean-
ing procedure for the printing decks. This procedure reduces solvent use by reusing
solvents that are otherwise discarded. Pre-used solvent is used in the first stage to
remove the majority of the ink. In the second stage, a cleaner but still pre-used sol-
vent removes more ink. In the third stage, clean solvent removes any remaining ink.
Install Automatic On-Press Cleaning: When paired with solvent recovery, on-press
cleaning systems use much less cleaning solution than hand cleaning, while also hav-
ing a very short cycle time.
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Clean Anilox Rolls Promptly: Prompt attention will prevent the inks from setting,
thereby reducing the need for harsh chemicals. Clean rolls also produce more pre-
dictable ink densities, potentially reducing on-press waste and improving quality.
Use Alternative Methods to Clean Anilox Rolls: Printers can choose among many
alternatives for cleaning anilox rolls to reduce or eliminate the need for traditional
cleaning solvents. These alternatives use sonic cleaning, dry ice, lasers, polyethylene
beads, and sodium bicarbonate.
Recirculate Warm Press Air: Both solvent-and water-based printers can significantly
reduce their energy requirements by recirculating warm air from dryers.
Throughout the printing process
Use Safer Chemicals: Switching to inks, cleaning agents, and adhesives that contain a
lower percentage of VOCs and fewer HAPs may reduce risk concerns to worker health
and the environment.
Segregate Hazardous Waste: Segregating hazardous wastes allows disposal of pure
instead of mixed wastes. Because pure wastes are much easier to treat than mixed
ones, they are not only less expensive to dispose of, but also require less energy.
Return Containers: Using returnable containers prevents unnecessary waste genera-
tion and results in additional cost savings.
Track Inventory: Tracking chemical purchases and disposal can help to maintain a
minimum inventory on the shelf, thus reducing the amount of materials wasted. For
example, hazardous waste can be minimized by labeling inks with the date and hav-
ing a "first-in, first-out" rule, i.e., rotating the inks so that the oldest inks are used
first. This avoids disposing of expired ink as hazardous waste. Tracking systems
using bar codes take inventory control to an even higher level.
Make a Management Commitment: Management should establish, communicate,
and demonstrate its commitment to the concept of pollution prevention, to encour-
age company-wide source reduction in everyday practice. Management can assemble
pollution prevention teams of employees, incorporate pollution prevention into job
responsibilities, and provide incentives for employees to prevent pollution.
Train Employees: Pollution prevention training for company personnel may facilitate
process changes by educating workers on the need for such change. Training also
helps to encourage general source reduction and stimulate pollution prevention ideas
by personnel.
Monitor Employee Practices: Periodic monitoring helps ensure that source reduction
practices are followed.
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Seek Out and Encourage Employee Initiatives: Supporting, encouraging, and actively
acknowledging pollution prevention initiatives by company personnel can stimulate
innovative ideas for source reduction. This may be especially beneficial because
employees who are closest to the process are often in the best position to recommend
change.
Develop an Environmental Management System (EMS): An EMS is a set of man-
agement tools and principles designed to guide a company to integrate environmen-
tal concerns into its daily business practices.
DfE has developed an Integrated
Environmental Management System
Implementation Guide, which provides
technical methods, step-by-step guid-
ance, and worksheets for facilities that
want to implement an EMS. You may
download it from the DfE website
(www.epa.gov/dfe). For a printed copy,
contact EPA's National Service Center
for Environmental Publications:
Phone 800-490-91 98 or
513-489-8190;
Fax:513-489-8695;
e-mai :ncepimal@one.net;
or Internet:
www.epa.gov/ncepihom/ordering.htm
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References
1. U.S. Census, 1999 Survey oj'Manufactures.
2. U.S. Census. 1997. Commercial Flexographic Printing.
3. Flexo, December 1998. "1999 Industry Forecasts," p. 32.
4. National Association of Printing Ink Manufacturers. 2001 State of the Industry
Report, p 4.
5. Flexo, January 2001, p. 18.
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