A Cooperative Project
between the
U.S. Environmental
Protection Agency
and the
Printing Trade
Associations
Nationwide
   FOR
  THE
OtWNT
                                                           SCREEN PRINTING PROJECT CASE STUDY2
                US. ERA
                             SCREEN PRINTING
                         Changing Equipment
                               and Reducing
                              Solvent Use In
                          Screen  Reclamation
                             The Design for the Environment (DfE)
                             Screen Printing Project is a unique,
                             cooperative effort between the screen
                         printing industry and the U.S. Environmental
                         Protection Agency (EPA).  The voluntary
                         project helps screen printers improve their
                         efforts to reduce risks to their workers and
                         the environment in cost-effective ways.
                           EPA and the screen printing industry are
                         developing a series of case studies to illus-
                         trate how screen printers can improve their
                         environmental performance. This case study
                         describes a successful pollution prevention
                         program at Action Graphics, a commercial
                         printer in Louisville, Kentucky, that took the
                         initiative to minimize risks to workers and
                         the environment. In doing so, the company
                         purchased equipment that re-duced solvent
                         use and chose  safer alternatives for the sol-
                         vents it could not eliminate.
         Specifically, this case study shows:

          '  How the need for ink remover can be elimi-
            nated by:
            •  Reclaiming screens immediately after
              a print run.
            •  Using a high-pressure water system.
            •  Switching to more effective, safer
              emulsion and haze remover products.

         •  How the quantity of solvent used during
            the printing process can be greatly
            reduced by finding more efficient sol-
            vents and reusing rags.
                                                             Background
            Action Graphics produces point-of-pur-
         chase display products, such as shelving
         signs, banners, and window signs used in
         retail stores and fast-food restaurants.
         Traditional solvent-based inks are used in
         about 60 percent of the company's printing.
         and ultraviolet (UV) curable inks are used
         in 40 percent.  Action Graphics opened for
         business in 1979 and currently has 30
         employees, half of which are directly
         involved in printing processes.
            Over the past five years, Action Graphics
         has developed a creative and comprehensive
         approach to pollution prevention. Although
         a small shop with limited resources,  it has
         greatly reduced solvent use through many
         innovative changes. The primary change
         was the introduction of a high-pressure
         water  system, which eliminated the need
         for ink remover solvent.  In addition, the
         company substituted safer screen recla-
         mation chemicals, purchased a distiller,
         switched to a slower-evaporating solvent
         for screen cleaning during press runs,
         changed to a safer ink thinner, and devel-
         oped a rag reuse policy.  These changes
         lowered the company's level of volatile
         organic compounds (VOCs) and decreased
         its generation of hazardous waste.

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A Change in Screen
Reclamation Equipment
and Chemicals
   Action Graphics' owner, Joe Miller,
   began thinking about the unintended
   effects of the solvents the company
   used when representatives from the
   Occupational Safety and Health
   Administration (OSHA) visited the
   shop in 1991.  While the company
   was not exceeding OSHA levels for
   contaminants in the air, the visit
   made Miller more aware of the possi-
   ble respiratory health issues associat-
   ed with solvents used in the screen
   reclamation process.
   At that time, Action Graphics was
 using a traditional three-step screen
 reclamation process: first, workers
 applied an ink remover; second, they
 applied an emulsion remover; and third,
 they applied a haze  remover to eliminate
 any remaining ink and emulsion.  Each
 chemical product was washed off the
 screen with a low-pressure water sprayer
 at 400 to 500 pounds per square inch
 (psi). When needed, a degreaser also
 was used.
   The ink remover consisted of diace-
 tonealcohol (75 percent), methylchloro-
 form (10 percent), and 2-butoxyethanol
 (15 percent). Exposure to these ingredi-
 ents can cause adverse health effects.
Methylchloroform exposure, for exam-
ple, can cause dizziness, lightheaded-
ness, and mild eye and skin irritation,
and may have more serious effects with
long-term exposure.  The emulsion
remover's ingredients included phos-
phoric acid, which can cause burns after
prolonged exposure. The haze remover
contained sodium hydroxide, which can
also cause burns, and cyclohexanol,
which can irritate the eyes, nose, and
throat and possibly cause more serious
effects at high concentrations.  The
degreaser did not present health con-
cerns.
   Indeed, some workers found vapors
from the solvents to be overpowering at
times, making breathing difficult in cer-
tain areas of the plant and causing eye
irritation. In addition, operators occa-
sionally received burns when they used
some of the cleaning chemicals improp-
erly.
   To reduce these health risks, Action
Graphics completely overhauled its
screen reclamation process at the end of
1991. The key component of the new
process  was  a high-pressure water sys-
tem that met Miller's need to improve
worker health and the environment by
reducing solvent use. The  system also
promised to pay for itself in a reason-
able amount of time. Miller also con-
sidered but ruled out enclosed booths in
which solvents are reused. These were
economically infeasible for the relative-
ly low volume of screens reclaimed at
                   Action Graphics.
                     With the new
                   high-pressure
                   water system,
                   workers transfer
                   screens to the
                   reclamation area
                   immediately after
                   a press run.
                   Speed is essential
                   because it pre-
                   vents the  ink from
                   drying on the
                   screens.  Operators
                   apply the emulsion
                   remover with a
                   brush, then rinse
                   the screens by
                   shooting water
through them at a pressure of 3,000 psi.
The combination of not allowing the ink
to dry and using the high-pressure water
stream allows workers to flush out both
ink and emulsion without the use of ink
remover.  Eliminating the need for ink
remover decreased
the company's
annual solvent
use by approxi-
mately 770 gal-
lons, reduced
worker exposure
to potentially
harmful chemicals,
and saved over
$13,000 per year in purchasing costs.
   Action Graphics also changed its
emulsion remover to sodium metaperio-
date, which, unlike  the company's origi-
nal emulsion remover, does not cause
burns.  Although the new emulsion
remover is slightly  more expensive, it is
also more highly concentrated, so
Action Graphics uses less (see chart for
cost savings). Workers complete the
process by applying a new, less corro-
sive haze remover and rinsing it out
with water at 3,000 psi.
   Another advantage to the new high-
pressure water system is that it includes
filtration  equipment that reduces the
amount of waste from the reclamation
process discharged  into the sewer sys-
tem. The  filtration system removes all
particles 5 microns  or larger and keeps
the wastewater in compliance with local
sewer district requirements.
   Besides the environmental and
health benefits, the new equipment
and chemicals actually do a better job
of keeping the screens clean. In addi-
tion, the old caustic chemicals tended to
slowly eat away at the screens. The new
system causes less wear and tear on the
screens, so they need to be replaced less
often.
   One of the benefits of solvent reduc-
tion is that it almost always saves
money. All told, Action Graphics' new
system saves $9,400 a year in operating
costs.  Since the one-time capital cost
for the system was  only $13,300, it paid
for itself in less than 16 months.
Screen reclamation with a high-pressure water system

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  >JS EM
Comparison of Yearly
Operating Costs*

               Old System   New System
Ink Remover        $13,100           $0
Emulsion Remover    $5,000        $2,600
Haze Remover       $7,800       $10,900
Filter Media             $0        $3,000
Total              $25,900       $16,500
Yearly Operating Cost Savings: $9,400

""Although Action Graphics believes labor costs also were
reduced under the new system, specific data are not available.
A  Change in Solvents

 Used During Press

 Operation

   About a year after Action Graphics
 overhauled its screen reclamation system.
 another one of its solvents surfaced as a
 problem. Like many printers, Action
 Graphics used a solvent during the print-
 ing process to remove dried ink left on
 screens overnight or during lunch breaks.
 The quickly evaporating solvent, called a
 press wash, consisted of n-butyl acetate.
 toluene, n-butanol, and isopropanol.
   In 1989, Action Graphics  purchased a
 distiller to reclaim its press wash solvent
 and consequently reduce its hazardous
 waste disposal and solvent costs.  As a
 result, the company was able to reuse
 roughly 100 gallons of solvent over the
 course of a year, for a savings of about
 $500 annually.  Although this early
 change was a step in the right direction.
 when Action Graphics' management
 applied for a permit with the local Air
 Pollution Control Board in 1992, they
 realized that more had to be done.
 During the application process, the shop
 discovered that much of its VOC emis-
 sions were coming from the quickly
 evaporating press solvent.  The board
 found that the level of VOCs on the
 application triggered ordinances that
 required Action Graphics to perform a
 best achievable control technology test to
 find ways to decrease its VOC emissions.
 These ordinances help protect both the
 environment and worker health, since
 VOCs can contribute to air pollution and
 exposure to VOCs can lead to adverse
 health effects.
   Some of the
changes Action
Graphics explored
to reduce these
environmental and
health effects
included using
thermal incinera-
tion, catalytic
incineration, or car-
bon absorption.
Thermal and cat-
alytic incineration
involve burning
VOCs that are cap-
tured in a dryer.
Carbon absorption
removes VOCs
through activated
carbon, which peri-
odically must be sent out for reactivation.
Through a cost-benefit analysis, Action
Graphics found that these processes
required a large capital investment.
Since Action Graphics is a small shop, a
large financial investment was out of the
question. The company  decided that
chemical reformulation of its press wash
was a more affordable alternative.  In
addition, chemical reformulation
promised to stop VOCs from being gen-
erated in the first place, a true pollution
prevention alternative, instead of trying
to capture the VOCs after generation.
   Finding a new  solvent was no easy
task, however. The  company spoke with
other screen printers, distributors of
national brands that are marketed as
environmentally friendly, and local chem-
ical suppliers.  Action Graphics found
that formulations from local chemical
suppliers were much less expensive than
national brands and  through trial and
error found one that met its needs.
Action Graphics switched to a solvent
that contains aromatic solvent naphtha
(60 percent), l-methoxy-2-propanol (30
percent), and oxybispropanolmethylether
(10 percent).  This mixture evaporates
much more slowly than the company's
traditional solvent, thereby decreasing
Action Graphics' total VOC emissions.
   Workers did not like switching to this
new  solvent, however. Since it evapo-
rates more slowly, press  operators were
concerned that they  would have to check
more carefully to  see if it was completely
Screen cleaning with a slowly evaporating press wash
                    evaporated before continuing a press run.
                    To address this issue, company manage-
                    ment wrote a letter to the press operators.
                    The letter explained that the new solvent
                    really did not require any additional
                    effort and that the switch was not only
                    necessary to comply with regulations, but
                    also helped create a healthier work envi-
                    ronment.  Employees gradually adjusted
                    to the new procedure.
                       The company not only reduced its
                    VOCs by using the new solvent, but also
                    reduced the total quantity of solvent used.
                    since press operators needed less of the
                    slower-evaporating sol-
                    vent to do the same
                    job.  This switch
                    cut solvent usage
                    from approxi-
                    mately 1,200
                    gallons per year
                    to 300 gallons.
                    Although the new
                    solvent costs a little
                    more per gallon, the com-
                    pany saves about $2,300 a year in pur-
                    chasing costs because  it  uses so much
                    less of the new product.
                       At the same time that the Air Pollution
                    Control Board suggested  that Action
                    Graphics reduce  its VOC emissions from
                    its press wash solvent, the board also
                    noted that the company was close to the
                    emissions limit for ethylene-based glycol
                    ether compounds. If the company
                    exceeded the limit, it would move to a
                    higher emissions category under Title V

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            FOR
            THE
of the Clean Air Act and be subjected to
a costly permit application process.
Many of the company's inks and thin-
ners contained these compounds.
Action Graphics followed the same steps
it took to locate a new press wash and
found a new ink thinner that consisted of
safer chemicals, l-methoxy-2 propanol
(85 percent) and oxybispropanolmethyl-
ether (15 percent), which are not listed
as hazardous air pollutants.  Although
the company saw no reduction in solvent
usage, these safer chemicals cost less
than the glycol ether ink thinner, saving
the company approximately $900 a year.
Continued Improvements    For More Information
Rag Reuse
   Another proposed solution for reduc-
ing solvents from Action Graphics' best
achievable control technology test was
to purchase a centrifuge to reclaim sol-
vent from used rags. The company
found in its cost-benefit analysis, how-
ever, that for its low volume of rags, a
centrifuge was not the best option.
Instead, the company instituted a policy
to reuse the rags as many times as possi-
ble before disposal.  Now, instead of
press operators always reaching for a
new rag each time they clean a screen,
they are asked to reuse a rag as long as
they are running the same color ink.
When they change inks, they also
change their rags.
   Eventually the heavily  soiled rags are
sent to an industrial laundry.  Action
Graphics does not reuse rags  from the
laundry, however, because the laundry
washes rags that are used for many pur-
poses, including rags from metal shops.
These rags often retain minute metal
pieces, which would destroy Action
Graphics' screens.  Instead, the laundry
provides the rags to other companies
that do not need to use them on fragile
equipment.
   The participation rate for rag reuse
has not been as high as the company's
management would like, because clean
rags do a better job cleaning screens.
Action Graphics hopes increased educa-
tion will help employees understand the
benefit of generating fewer solvent-
soaked rags.
   While your print shop may use differ-
ent inks or create different products than
Action Graphics, you may still be able
to learn from Action Graphics' deci-
sions. When problems were identified,
the company actively sought out creative
solutions.
   Company management weighed all
   their options carefully, spoke to other
   printers, and when appropriate con-
   ducted cost-benefit analyses before
   making changes.
   Purchasing the high-pressure water
system, switching press wash solvents
and ink thinner, and instituting a rag
reuse policy resulted in win-win situa-
tions. These changes enhanced screen
reclamation performance, benefitted
worker health and the environment, and
saved the company money. If you are
interested in these improvements, you
can learn from Action Graphics'  suc-
cess.
   Action Graphics' progress probably
will not stop there, however.  One of the
key factors behind Action Graphics'
success has been the company's contin-
ued self-evaluation and openness to new
ideas. Action Graphics' management is
always on the lookout for new ways to
improve working conditions and mini-
mize the company's impact on the envi-
ronment.  One future improvement the
company is considering is switching
over completely to UV curable inks,
eliminating its use of solvent-based inks.
   For more information on the tech-
nologies in this case study, contact your
equipment suppliers.  For more informa-
tion on other technological and chemical
alternatives, refer to the summary book-
let Designing Solutions for Screen
Printers—An Evaluation of Screen
Reclamation Systems.  For more infor-
mation on EPA's DIE Program or to
obtain additional case studies, bulletins,
and other related materials, contact:

   Pollution Prevention Information
    Clearinghouse (PPIC)
   U.S.  EPA
   401 M Street, SW (7409)
   Washington, DC 20460
   Phone:  202-260-1023
   Fax:  202-260-4659
   For more information on this case
study and trade association information,
contact:
   Screenprinting and Graphic Imaging
    Association International (SGIA)
   10015 Main Street
   Fairfax, VA 22031
   Phone: 703-385-1335
   Alternatively, you can visit the DIE
home page on the World Wide Web at
http://www.epa.gov/dfe or the SGIA
home page at http://www.sgia.org
   Also  be sure to investigate your local
health and environmental regulations.
Local agencies are familiar with priority
issues in your area and can help you find
the best ways to prevent pollution in
your community.
 What Is the Design for the Environment

Screen Printing Project?

   The U.S. Environmental Protection Agency's (EPA) Design for the
Environment (DfE) Screen Printing Project is a voluntary project that
encourages printers to consider environmental concerns along with cost
and performance when purchasing  products to use in their facilities.
Replacing hazardous chemicals with environmentally safer substitutes
is one way to reduce the impact of printing on the environment while
maintaining product quality. Many printers, however, have limited time
and resources and therefore need help identifying and testing environmentally safer substi-
tutes.
   DfE fills this information gap. EPA has teamed up with screen printing industry represen-
tatives (including trade associations, printers,  and suppliers) in the DfE Screen Printing
Project.  The project's goal is to evaluate and  publicize pollution prevention opportunities in
screen printing, particularly in the screen reclamation process.

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