United States
Environmental Protection
Agency
Air and Energy Engineering
Research Laboratory
Research Triangle Park, NC 27711
Research and Development
EPA/600/SR-95/063
June 1995
EPA Project Summary
Evaluation of Barriers to the
Use of Radiation-Cured
Coatings in Can Manufacturing
Beth W. McMinn and Steven R. Church
The full report gives results of a study
to investigate and identify the techni-
cal, educational, and economic barri-
ers to the use and implementation of
radiation-cured coatings in can manu-
facturing. The study is part of an EPA
investigation of current industrial use
and barriers to the extended use of
radiation-cured coatings in Source Re-
duction Review Project (SRRP) and
maximum achievable control technol-
ogy (MACT) standards development cat-
egories. Among the important barriers
were (1) an applied wet film thickness
of >120 mg per can of ultraviolet (UNO-
curable overvarnish needed on most
trial runs; (2) lower than expected en-
ergy savings; (3) inadequate cure of
overvarnish; and (4) ink "pick off" dur-
ing the wet-on-wet application of the
overvarnish to the inks. The report sug-
gests projects that could help over-
come technical, educational, and eco-
nomic barriers identified. Among the
opportunities discussed were (1) set-
ting up a trial with a can manufacturer
who is interested in using UV-curable
inks and coatings; (2) conducting re-
search on cationic inks and coatings,
which have been billed as the next gen-
eration of UV-curable inks and coat-
ings; and (3) working with Radtech, the
trade association representing the ra-
diation-curable coatings industry, to
develop a UV-curable coating that could
be approved by the Food and Drug
Administration for direct contact with
food.
This Project Summary was developed
by EPA's Air and Energy Engineering
Research Laboratory, Research Tri-
angle Park, NC, to announce key find-
ings of the research project that is fully
documented in a separate report of the
same title (see Project Report ordering
information at back).
Overview
Section 4(b) of the Pollution Prevention
Act (PPA) of 1990 requires EPA to review
regulations of the Agency prior and sub-
sequent to their proposal to determine their
effect on source reduction. In support of
the PPA, EPA established the Source Re-
duction Review Project (SRRP) to focus
this review on pending regulations (and
anticipated regulated industries) under the
Clean Air Act (CAA), the Clean Water Act
(CWA), or the Resource Conservation and
Recovery Act (RCRA). One of the goals
of SRRP tasks is to ensure that source
reduction and multimedia issues are con-
sidered during the development of upcom-
ing air, water, and hazardous waste stan-
dards.
One important set of regulations under
the CAA, and a focus of SRRP, are the
standards for maximum achievable con-
trol technology (MACT) to reduce emis-
sions of hazardous air pollutants (HAPs).
Promulgation of these regulations began
in 1992 and will continue through the
1990s and into the next century. The
MACT standards offer EPA an excellent
opportunity to use SRRP to incorporate
pollution prevention measures into the up-
coming standards for specific source cat-
egories. Pollution prevention efforts offer
economic and reduced health and eco-
logical risk benefits to many sectors of
society that are not available through tra-
ditional pollution control methods.
Printed on Recycled Paper
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In support of the SRRP Program, MACT
standards development, and the PPA, EPA
is investigating pollution prevention op-
portunities for product and material sub-
stitutions that help industry to reduce
waste. The objective of this project was to
investigate the current industrial use and
barriers to the extended use of waterbased
and radiation-cured coatings in SRRP and
MACT categories. Metal Cans (SIC 3411),
an industry facing upcoming MACT stan-
dards, was selected as an industrial seg-
ment for study. When the MACT stan-
dards are developed, EPA will have a
better understanding of which coating tech-
nologies are feasible pollution prevention
alternatives for the industry.
The full report gives results of a study
to investigate and identify the technical,
educational, and economic barriers to the
use and implementation of radiation-cured
coatings in two-piece metal can manufac-
turing. This project involved preparing cat-
egory analyses, identifying and classifying
the use and implementation barriers, evalu-
ating and assessing the environmental
impacts, and identifying pollution preven-
tion and source reduction research oppor-
tunities in the two-piece metal can indus-
try. Information was collected for this
project from a review of current technical
literature, cooperation with industry lead-
ers and the leading trade organization,
and visits to three can manufacturing fa-
cilities. (One of the visits was to a three-
piece can manufacturing facility; however,
the report focuses on two-piece manufac-
turing.)
This project was initially intended to
study both ultraviolet (UV) radiation-cured
and waterbased screen printing inks as
possible alternatives to solvent-based inks
with high volatile organic compound (VOC)
emissions. During the project, it became
evident that the focus should be on UV-
curable inks and coatings. The current
industry standard is to use waterbased
inks and coatings that contain 6 to 15%
VOCs. UV-curable inks and coatings con-
tain <1% VOCs and would significantly
reduce emissions from two-piece" can
manufacturing operations.
In the can manufacturing industry, there
is debate over the economic and process
benefits that UV-curable inks and coat-
ings offer. The Coors can manufacturing
plant in Golden, CO, has been success-
fully using UV-curable inks and overvarnish
to coat the exterior of its cans since 1976.
The UV technology has provided Coors
with a number of benefits including (1)
reduced energy costs; (2) less downtime
for maintenance and repairs; (3) less floor
space occupied by the drying/curing ovei
and (4) employee satisfaction with the n
duced operating temperatures and simple
procedures of the UV-curing oven. Coors
claims that the benefits of a UV system,
particularly the reduced energy costs, com-
pensate for the higher material costs of
UV-curable inks and coatings.
Ball Corporation had a different experi-
ence with UV-curable inks and coatings
when it established a UV trial line at its
Findlay, OH, plant in 1986-87. The com-
pany encountered several technological
and economic barriers that prevented Ball
from expanding its use of UV technology
beyond the trial stage. Some of the impor-
tant barriers were (1) an applied wet film
thickness of >120 mg per can of UV-
curable overvarnish needed on most trial
runs; (2) lower than expected energy sav-
ings; (3) inadequate cure of overvarnish;
and (4) ink "pick off during the wet-on-
wet application of the overvarnish to the
inks.
The full report divides the barriers to
implementing UV-curable inks and coat-
ings into three categories: technical, eco-
nomic, and educational. Each category is
examined separately.
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Beth W. McMinn and Steven P. Church are with TRC Environmental Corp., Chapel
Hill, NC 27514.
Carlos M. Nunez is the EPA Project Officer (see below).
The complete report, entitled "Evaluation of Barriers to the Use of Radiation-Cured
Coatings in Can Manufacturing," (Order No. PB95-215810; Cost: $27.00, subject
to change) will be available only from:
National Technical Information Service
5285 Port Royal Road
Springfield, VA 22161
Telephone: 703-487-4650
The EPA Project Officer can be contacted at:
Air and Energy Engineering Research Laboratory
U.S. Environmental Protection Agency
Research Triangle Park, NC 27711
United States
Envirbnmental Protection Agency
Center for Environmental Research Information
Cincinnati, OH 45268
Official Business
Penalty for Private Use $300
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EPA
PERMIT No. G-35
EPA/600/SR-95/063
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