Green Printing: Perception vs. Reality and the UV EdgeOctober 16, 2010 By C. Clint Bolte
C. Clint Bolte & Associates, Chambersburg, PA
Conventional inks not only have to dry via evaporation, but up to 50 percent of the initial ink film applied is lost through evaporation into the atmosphere and absorption into the sheet. Since UV inks cure instantly when exposed to UV light, drying time is eliminated and no solvents are released or absorbed into the substrate, as is common with conventional inks. The UV process releases no VOCs (Volatile Organic Compounds), making it much safer for operators and the environment.
“UV is regarded now as having the same risks as other major processes,” according to Ehrlitzer. “It is no more hazardous than using solvent- or water-based inks. With all these processes, the main requirement is that the printing is done in the right way.”
Other important advantages of UV’s instant drying are faster turnaround times and non-marking or smudging of the image on finishing equipment. The press operator now has the option of backing up the job right away or sending it straight to the bindery when printing is complete. This could save work-in-process floor space.
Older Solvent-based vs. Current UV Systems in Sign Production
As sign-printing technology has evolved from screen printing to wide-format digital printing, a number of the same “green” lessons have been learned as solvent-based fluid inks are replaced by UV inks. While very few commercial, label or package printers also offer digital wide-format signs and banners, the “green” message shared with the different markets is so similar it is actually reinforcing.
Large-format inkjet printers previously used solvent-based technology to adhere ink to substrate. The process entails mixing ink pigment with a solvent vehicle to create liquid ink. The printer head(s), one for each color, then transfer the liquid onto a substrate. As the solvent evaporates a hard layer of ink remains.
Water-based inks work similarly except more water is often absorbed into the paper rather than evaporating into the atmosphere as with solvent. While water is harmless, solvents in printing are toxic. To ensure the safety of employees and customers at a printing facility, complex ventilation systems must be installed to remove and capture hazardous airborne chemicals, called VOCs.
UV printing is fast becoming the new industry standard in signage production. Because there are no solvents used, this system produces no dangerous VOCs, requires no ventilation, has a higher percentage of recyclable content, and cuts cost because of reduced drying time. In addition, UV printed foil-type metallic inks on paper and plastic yield a fully recyclable product.
Eco-friendly UV Supplies Advancements
A universal problem, which is experienced by all sheetfed and web UV printers, is the tendency of the printing blankets to fail prematurely. Blanket failure is typically caused by a latent image of the printing form adhering to the blanket after a few thousand impressions. This latent image cannot be removed with conventional blanket wash. UV printers often refer to this phenomenon as “ghosted image,” “latent image,” “burn-in” or “image memory.”
Frustrated with the premature failure of UV printing blankets compared to conventional printing blankets, a group of experienced professionals in the UV printing industry—including chemists, consultants and a high end UV printing plant (that agreed to host the trial and error testing)—formed a dedicated research and development team. Their goal was to develop a UV blanket rejuvenation process.
After four years of beta testing and significant funding, the team developed a rejuvenation program, which is currently patent pending. The resulting specialized technology, which was awarded a PIA/GATF InterTech Award in 2007, is sold throughout the United States, Canada, and Asia under the brand name Enviro Image Solutions (EIS).
Printers who subscribe to the EIS program are reporting that their blankets are being refurbished four times on average. Additionally, they assert saving of over 65 percent of the cost of new blankets by embracing this refurbishment program.
During the test phase, a UV printer sends 10 spent printing blankets to EIS. The blankets are rejuvenated and returned to the printer at no cost. The printer uses the rejuvenated blankets for self-assurance that the blankets print like new ones.
Once a successful test is run, EIS provides a transport cell, which safely stores and protects approximately one hundred spent blankets. Once the cell is full of spent blankets, the printer ships it to EIS’ facilities in Canada.
Accompanying the returning rejuvenated blankets is a report indicating the number of times blankets have been rejuvenated and suggesting corrective measures to further improve the rate of rejuvenation. EIS works with each printer to maximize savings and environmental benefits as part of the program. Some printers post these reports in their pressroom or employee lounges as educational tools.
Printers indicate that these reports have proven beneficial not only because they pinpoint hidden costs that otherwise go unnoticed, but also because, once issues are corrected, can help to increase production efficiency.
Clients who subscribe to the service generally improve their rejuvenation success rates with each order. Once accustomed to the program, many typically enjoy a 90 percent rejuvenation success rate, with the remaining unusable blankets being recycled. On a periodic basis (and at least annually for the lowest blanket volume users), EIS provides a report documenting the accumulative cost savings realized as well as the amount of rubber and fabric prevented from going into the landfill. EIS invoices the printer for only those blankets that have passed stringent quality control measures. As such, the interests of EIS and the printer are significantly aligned.
EIS can also provide a document illustrating the recycling process that unusable blankets undergo. Printers send copies to interested corporate clients who are typically pleased to learn of all the “green” and environmentally sensitive initiatives being supported by their suppliers.
What About the Negatives?
With all of the aforementioned positives, it wouldn’t be fair to omit discussing some of the negatives. But before doing so, it is appropriate to address a common question: What is sustainability? In 1987, the Brundtland Commission defined sustainability as “meeting the needs of present generations without compromising the ability of future generations to meet their needs.” In printing, and in most other industries, this can be achieved by striving to eliminate the use of fossil fuels, heavy metals and harmful chemicals and compounds, or to work toward alternative solutions, to prevent the physical degradation and destruction of nature.
Many printers are discarding tons of spent UV and conventional printing blankets into local landfills. Immediate attention and corrective action is needed to stop this unsustainable practice. Waste prevention and recycling efforts can help us better manage the solid waste that we generate. While the EIS program certainly reduces waste, this supplier continued the research to find partners that could recycle spent blankets or possibly use them as an alternative energy source.
EIS found a corporate neighbor, British Columbia’s Lafarge Cement, to help achieve this goal. This global firm’s BC cement plant is listed as one of the province’s top 10 emitters of carbon dioxide and related gases that are believed to contribute to global warming. This occurs through high-intensity combustion of fossil fuels, such as coal, in the process of manufacturing cement.
However, Lafarge discovered that some combustible biomass waste materials could be substituted for coal. This reduces the amount of coal required, coal’s natural undesirable effluent and elimination of a solid waste. The Lafarge kilns burn at such high temperatures that the hazardous emissions from burning printing blankets are avoided and the ash that would otherwise be emitted is captured and used in solid form in the cement itself. With the help of carbon offset funding and through the contributions of companies like Enviro Image Solutions, Lafarge is working on a system to combine a variety of alternative fuels to become integral to its manufacturing process. Process-engineered fuel reduces annual greenhouse gas emissions and prevents the release of methane gas, as organic materials no longer decompose in landfills.
Other “Green” Suppliers
Many other case studies are available. For example, UV lamp manufacturers continue to upgrade their manufacturing process to extend the life on UV lamps, along with providing upgrades and recycling services on the lamp housing units. The printing industry can also expect to see less energy used with UV ink curing in the future.
Printers should insist that their supplier partners prepare news releases about their own internal eco-friendly efforts and improvements, which the printers can pass on to employees and corporate clients to provide proof of the ever changing eco-sensitivity being endorsed by the printing industry. PI