A common misconception in water based ink cleaning is the thought that to be effective it would need to have a high pH and thus, be hazardous to the user or equipment. In reality there are two parts for these cleaners to be effective, pH and alkalinity. The alkalinity levels in these cleaners is what causes them to be corrosive and hazardous to the user. Alkalinity and pH can be combined together at the correct levels for optimal water based and UV ink cleaning in Flexo printing.
pH
The numbers 1-6 on a pH scale relates to acids, 7 represents neutral (water), 8-14 refer to bases. The acids in cleaners are usually used to clean rust, hard water stains and lime scale, while bases are used to remove organic based materials or stains. Since we are referring to ink, the focus will be on high pH alkaline cleaners. High pH levels, generally those above 12.5, are considered dangerous and certainly can be. The EPA developed a program for environmentally friendly cleaners called Designed for the Environment (DFE). In the guidelines, the products require a pH of less than 11.5, unless they are proven to be non-corrosive to the skin or eyes. http:www.epa.gov/dfe/pubs/projects/formulat/dfe_criteria_for_cleaning_products_10_09.pdf
Alkalinity
Alkalinity is a measure of how much acid the solution can neutralize. Alkalinity is also the push behind pH in a cleaner. Cleaners with high levels of pH and high levels of alkalinity have a lot of push behind them, which means they have a slow push and keep pushing for several minutes. Cleaners with a high pH, even beyond the standard set of 11.5 that also have very little alkalinity, have very little push behind them. This means the skin receives a quick push, usually done in seconds, unlike higher alkaline or caustic cleaners which can push for a very long time causing rapid damage to the skin. Human skin can handle the quick pushes.
Solution
APR's line of Simply Clean products contains cleaners that fit the description of high Ph and low alkalinity. Simply Clean AC Concentrate has a pH of 12.58 but, very low alkalinity, making it non caustic and safe for the environment. These products will perform as well, and in many cases out perform caustic cleaners for water based and UV ink cleaners.
If you want to learn more about this subject, please feel free to reach out to us by calling 1-800-445-4017, or by e-mail at: [email protected].
All Printing Resources has formed our Technical Solutions Group (TSG) to encompass our full range of expertise in all critical areas of the flexo process. This team is made up of industry professionals dedicated to being up-to-date on new technologies along with best practices. They are armed with the latest in diagnostic tools, and are experienced in problem-solving that can achieve sustainable results. The TSG have walked in your shoes, and have felt your pain.