From: Gary Jones(firstname.lastname@example.org )
Date: Thu, 16 Aug 2001 00:24:42
In response to your question:
1. The shelf life of UV ink has been reported to be about one year.
2. Waste ink will have to be evaluated just as any other waste product relative to the RCRA definition of hazardous waste. The presence of NVP will not cause it to fail TCLP. Most uncontaminated UV inks are not classified as hazardous, but it is imperative to have the waste inks profiled prior to classification. The ink supplier may have some data to help in the profiling of the waste ink.
3. While there are limitation to UV inks in terms of compatibility with substrates, they have been successfully used in the manufacturing of folding paper boxes via the lithographic printing process. I know of several companies producing boxes that only use UV inks.
4. UV inks and coatings are generally more expensive and require lamps to cure the ink. Special blankets and rollers are also usually required. Since lithographic UV ink must behave the same as conventional inks, they will have the similar physical and flow characteristics as conventional inks. They are applied in the same manner as conventional inks, but in stead of drying, they cure when exposed to UV light. As you are investigating the use of UV inks, I would suggest that you also consider the new hybrid inks that have both conventional and UV cured components. They do not require as much press modification as pure UV inks while offering other performance benefits.
5. In terms of emissions, there can be some VOC emissions from the inks. Efforts at quantitating the specific amount have eluded the industry for quite some time. Currently, there is some work being performed to develop a VOC content test method for thin filmed UV cured inks and coatings. There is a method D5403 that can be used for thick film UV cured inks and coatings, the films created via lithographic printing are thin filmed. Determining the VOC content of thin filmed UV cured inks and coatings is important because there are no retention factors that can be used in quantitating these emissions. Until the formal test can be finalized, you need to contact the manufacturer of the inks to determine the VOC content of the ink. Uncured inks and coatings can have about 3-5% VOC content, but since many of the "volatile" components become part of the polymerized film, it is important to remember that any VOC content testing for radiation cured inks and coatings should be conducted only after the ink or coating has been cured. EPA has prepared a letter stating that they should be cured prior to testing.