A Cooperative Project
between the
U.S. Environmental
Protection Agency
and the
Printing Trade
Associations
Nationwide
FOR
THE
ONME
SCREEN PRINTING PROJECT CASE STUDY 1
U.S.EPA
SCREEN PRINTING
Reducing the Use of
Reclamation Chemicals in
Screen Cleaning
Being responsive to the environment
means learning new procedures and
using new tools to do the same job
with less negative environmental impact.
Decisions about the purchase of equipment
and chemicals for screen reclamation or other
production processes depend not only on
cost, availability, and performance, but also
on whether environmental requirements can
be met. Meeting environmental requirements
means understanding the comparative human
and ecological risks of the alternatives being
considered.
This is the first in a series of screen
printing industry case studies that illustrates
how printing facilities can improve their envi-
ronmental performance. This study describes
a successful pollution reduction program at
Romo Incorporated, a screen printer in De
Pere, Wisconsin.
Other screen printers can learn from
Romo's experience and from the way that the
company searched for safer alternatives.
In particular, this case study shows:
• How a self-audit of ink remover products
used in screen cleaning led to the substitu-
tion of more environmentally appropriate
solvents at press side.
• How using a still to recover and reuse ink
cleaning solvent saved the com-
pany money.
• How using a high-pressure
water blaster and changing
product application tech-
niques allowed the company
to decrease the use of its recla-
mation chemicals.
The story of this company's experience
shows how problems can become opportuni-
ties and how environmental planning can be
good for business.
Background
Romo is a commercial screen printer
that produces a wide variety of products
including decals, banners, point of purchase
displays, and original equipment manufacture.
About 60 percent of the company's printing is
conducted with traditional solvent based inks
and 40 percent of its printing utilizes ultravio-
let (UV) curable inks
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FOR
Over the 40 years of its operation,
Romo has experienced increasingly
stringent environmental and health
regulations on local, state, and federal
levels, many of which have required
expensive changes or threatened high
fines for noncompliance. A change in
ownership in 1983 led company man-
agement to make a conscious decision
to stay ahead of the regulations.
The result was a management
and employee commitment to decreas-
ing the environmental impact of Romo
as much as possible without compro-
mising profits and competitiveness.
The story of Romo has been one
of continuous improvement. Romo
began by making a number of changes
to reduce its use of ink cleaning sol-
vent and emulsion remover. Soon after,
it began slowly introducing UV curable
inks to reduce volatile organic com-
pound (VOC) emissions. In early 1992,
Romo joined Environmental Protection
Agency's (EPA's) 33/50 Program, a vol-
untary pollution prevention initiative,
targeting 17 high-priority chemicals. As
part of the program, Romo has worked
to reduce the use of two of these
chemicals, toluene and methyl isobutyl
ketone, which are key ingredients in
the screen cleaning product that was
used at the company. Romo is continu-
ing its quest for further improvement
by seeking methods to reduce its use
of haze remover.
Target
Opportunities
For Change
In 1987, Romo began looking
for pollution prevention opportunities,
particularly in the screen reclamation
process. Since screen reclamation is
crucial to screen durability and the
quality of printing, but also requires a
number of expensive and harsh chemi-
cal products, the process seemed to
provide a large potential to prevent
pollution and save money. In addition,
since wastewater from the reclamation
process washed down drains directly
to a sewage treatment plant, Romo
wanted to be sure that the water con-
tained no environmentally damaging
chemicals.
Consider Possible
Solutions
During its self-audit, Romo
decided to concentrate on all three parts
of screen reclamation: ink removal
(screen cleaning), emulsion removal, and
haze or "ghost image" removal. The
company sought employee suggestions
and cooperation for improvement in
each area. The company management
decided to search for ways to reduce
chemical risk and prevent pollution
through three strategies:
• Reducing the volume of all products
used
•Testing alternative application
techniques
• Experimenting with alternative for-
mulations of traditional products.
Improving The Ink
Removal Process
Begin In-Process
Recycling
A new plant engineer who
arrived in 1986 brought with him an
idea for reducing Romo's consumption
of screen cleaning product. His idea
was to recover screen cleaning solvent
for reuse through an in-process recy-
cling still. At that time, Romo was using
between 20 and 40 gallons of solvent
per day. Used screen cleaning product
drained through a trough into an open
tank, then was lightly filtered and
hosed back onto the screen. Unfortu-
nately, the open tank allowed large
quantities of solvent to evaporate, and
an inefficient filtering system left the
recovered solvent dirty and effective.
Management decided to act on
the plant engineer's idea and install a still
at a one-time cost of $2,900. This invest-
ment was recovered within seven weeks
through reduced solvent costs. The new
still is a closed system that utilizes a
heating and filtering system to remove
pigment before pumping solvent back
for reuse. The 5-gallon still is cleaned
once or twice per week; although the
solvent becomes discolored over time,
the same 55-gallon solvent container
lasts for three to four weeks. When the
solvent becomes too dirty to clean
effectively, Romo disposes of the ink-
contaminated solvent as a
hazardous waste.
Through the use of the
still, Romo was able to
reduce its consumption
of cleaning product to
only one 55-gallon drum
every three to four weeks (even in con-
junction with an increase in facility pro-
duction). This saves the company $83
per day or $20,750 per year in solvent
procurement costs alone. The decreased
consumption in screen cleaning product
also contributes to a healthier working
environment, since employees are no
longer exposed to large quantities of
evaporated solvent.
Change To Alternative
Application Techniques
By working together with compa-
ny employees, Romo discovered new
work practices that further reduced the
volume of screen cleaning product need-
ed. For years, the screen cleaning sol-
vent was applied in the same way, by
hosing the solvent onto the screen. One
creative employee suggested adding an
adjustable spray nozzle, like that on a
garden hose, in order to provide more
direct and efficient application of the
product. The nozzle, paired with better
use of brushes to loosen the ink, was
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U.S.EPA
able to reduce the amount of solvent
needed for each screen.
Further reductions in solvent use
were made in 1991 by creating a pres-
sure control device for the spray noz-
zle. The device was simply a small
piece of wood secured under the han-
dle of the nozzle by a locking band.
Since the wood prevented the screen
reclaimers from pushing the nozzle
past a certain point, the amount of sol-
vent being sprayed was controlled.
Investigate Alternative
Products For Toxics Use
Reduction
In keeping with their 1992 com-
mitment to EPA's 33/50 Program, Romo
decide to reduce its use of toluene and
methyl isobutyl ketone by 50 percent
by 1995. Management decided to test
some alternative screen cleaning prod-
ucts that contained less of these ingre-
dients.
Romo was aware of a number of
press-side screen cleaning products
claiming to be "biodegradable," "drain
safe," or "environmentally safe." After
ruling out several that contained
toluene, methyl isobutyl ketone, and
other chemicals listed by EPA's 33/50
Program as ingredients of environmen-
tal concern, Romo decided to test a
few products that had been recom-
mended by other screen printers. One
particularly promising product, formu-
lated for process cleaning at press side,
primarily consisted of a mix of propy-
lene glycol monomethyl ether, propy-
lene glycol monomethyl ether acetate,
and cyclohexanone. Although expen-
sive at $13 per gallon, as opposed to
$3 per gallon for the solvent Romo was
using at the time, the product per-
formed well, and Romo decided to use
the less hazardous product for press
side cleaning. Savings generated by
using less reclaiming solvent were used
to fund the increased cost of the new
press-side screen cleaning product.
In 1991, Romo used 12,382
pounds of toluene and 6,098 pounds of
methyl isobutyl ketone. By making the
switch to the new press-side screen clean-
ing product, Romo was able to reduce its
use of these chemicals by approximately
70 percent, bringing the use of toluene
down to 3,6ll pounds and methyl
isobutyl ketone down to 1,779 pounds.
Change Emulsion
Remover Approach
With a number of successes
behind it, Romo continued its search
for other potential pollution prevention
opportunities by looking at the emul-
sion removal process. Fol-
lowing up on an
advertisement, Romo test-
ed and then bought an
extremely high-pressure
water blaster (290 pounds
per square inch [psi]) for
$2,450 that harnessed the
physical power of water
pressure to reduce the
amount of chemical emul-
sion remover product used
on each screen. Romo was
concerned that the
increased pressure might disturb screen
tensioning or deteriorate the mesh. But
after five years of successfully using the
high-pressure blaster, Romo was confi-
dent enough that the equipment did not
deteriorate the mesh that it bought
another even higher pressure (1,500 to
4,000 psi) blaster for $4,900.
Another way Romo reduced the
amount of emulsion remover needed
was by diluting it with water before
applying it to the screen. Although a
ratio of 1 gallon of full strength emul-
sion remover to 3 gallons of water was
previously used, the company found
that a further dilution of 1 gallon of
emulsion remover to 6 1/2 gallons of
water was just as effective.
The company has gleaned even
more savings by creating a new appli-
cator for emulsion remover. Formerly,
employees dipped a scrub brush into
the sliced open top of an emulsion
remover container before bringing the
brush to the screen. Unfortunately, it
was a messy practice, wasting expen-
sive emulsion remover by dripping it
on the floor. Instead, a Romo engineer
modified a 15-gallon drum by adding a
spray nozzle to evenly mist the emul-
sion remover onto the screen.
The plant engineer estimates that
the combination of the change in emul-
sion remover application technique, fur-
ther dilution of the emulsion remover,
and use of the high-pressure water blaster
has resulted in a 75 percent reduction in
emulsion remover use. This reduction
saved the company almost $3,800 per
year, which means that the high-pres-
sure water blaster paid for itself in
approximately 15 months.
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The Design for the
Environment (DfE)
Approach
For More
Information...
The Next Step: Change
Haze Remover Use
Romo continues to seek envi-
ronmental improvement by searching
for ways to minimize its use of haze
remover. Press operators concern that
haze remover makes a screen mesh
brittle and more likely to tear provides
a built-in incentive for reduction of its
use. Romo has taken several steps to
reduce the use of its haze remover. First,
the screen reclaimer applies haze
remover precisely to the part of the
screen that is stained. Second, employ-
ees try to remove ink and emulsion as
quickly as possible, since
the longer either materi-
al sits on the screen, the
more likely it is that the
operator will have to
apply haze remover.
Third, Romo is look-
ing for alternative chemicals by work-
ing with a local chemical supplier to
formulate an emulsion remover that
will eliminate ghost images and the
need for haze remover. The company
is also testing a method that the Screen
Printing Technical Foundation believes
can eliminate the need for a haze
remover. The technique requires that
the operator degrease and apply ink
degradant to the screen before apply-
ing emulsion remover.
This case study described how a com-
pany continuously improved its opera-
tions by identifying toxic use reduction
and pollution prevention opportuni-
ties, encouraging creative new work
practices, and trying out new methods
and products. By changing work prac-
tice techniques and purchasing new
equipment, the company realized sub-
stantial cost savings.
The result is a methodology that
is affordable, effective, readily adapt-
able, and can be transferred to other
printers. Environmental benefits
demonstrated in this case study
include reduced fugitive air emissions,
less solvent discharged to the water
system, decreased toxic chemical pur-
chases, and a less hazardous work
environment.
The EPA's Design for the Envi-
ronment (DfE) Screen Printing Project
seeks to provide information to printers
and companies (often through their
trade associations) about the compara-
tive risk and performance of alternative
chemicals, processes, and technologies.
This will help printers to make more
informed choices about the products
they use in their facilities. Information
on alternatives for screen cleaning and
reclamation are available from the DfE
Screen Printing Project.
If you would like more informa-
tion about Romo's experience, contact:
Jonathan Darling
Romo Incorporated
800 Heritage Road
P.O. Box 800
De Pere, WI 54115-0800
414-336-5100
For copies of this bulletin, other
DfE Screen Printing Project materials,
or for more information about the pro-
ject, please contact:
Pollution Prevention Information
Clearinghouse (PPIC)
U.S. Environmental Protection Agency
401 M Street, SW (3404)
Washington, DC 20460
Telephone: 202-260-1023
Fax: 202-260-0178
or
Screenprinting and Graphic Imaging
Association International (SGIA)
10015 Main Street
Fairfax, VA 22031
Telephone: 703-385-1335
Fax: 703-273-2870
You may also contact the DfE Home
Page at: http://es.inel.gov/dfe or the
SGIA Home Page at
http://www.sgia.org/
Recycled/Recyclable
^V^
Printed with Soy/Canola Ink on paper containing at
least 50% recycled fiber.
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