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 ------- 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. ------- 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 BULK RATE POSTAGE & FEES PAID EPA PERMIT No. G-35 EPA/600/SR-95/063 ------- |