Vegetable-based Ink for a Healthy Environment
As if the whole paper recycling issue wasn’t confusing enough, there is also the matter of environmentally-friendly ink. The ink landscape is constantly evolving. For example; it used to be that the answer to environmentally-friendly ink was simply to use a soy-based ink. However, The National Soy Ink Information Center ceased operation recently. We think this was probably due to the fact that pure soy ink never become viable industry-wide due to it’s slower than normal drying time.
So what is taking the place of soy? Vegetable-based inks, in some cases with partial soy content, are rapidly gaining popularity. MU Printing Services is currently testing two of these:
- INX ProMark This ink is soy/vegetable oil content (22-24 percent depending on the color). It has a VOC (Volatile Organic Compounds—the lower the better) ranging from 18.5-19.8 percent. Conventional inks typically have a VOC range of 25-35 percent.
- Kohl & Madden Freedom The vegetable oil range for this ink is from 25-35 percent. VOC’s average 1.0 lb/gallon. On the technical data sheet we obtained for this ink, the VOC rating was not stated as a percentage, rather as a weight per gallon ratio.
Why do we have to test the ink before switching exclusively to it? Mainly to determine the ink's performance on our presses with our prevailing conditions. In spite of the fact we strive to maintain stable internal conditions, with outside humidity ranging from 10 percent in the winter to 95 percent in the heat of summer, it is nearly impossible.
- We are very concerned with drying time. We almost always print on both sides of the paper. After we have run it through the press once, we have to run it back through the press to print the other side.
- If the ink doesn’t dry very quickly, you have one of two unacceptable choices: run it anyway and have smeared ink on the printed piece, or wait until the ink is dry (sometimes literally days) and very likely miss the deadline.
So we test the ink exhaustively before making a wholesale switch to something different.