Soy ink

Soy ink is a kind of ink made from soybeans. As opposed to traditional petroleum-based ink, soy-based ink is more environmentally friendly, might provide more accurate colors, and makes it easier to recycle paper. It is slower to dry than many inks.

In the late 1970s, the Newspaper Association of America was looking for different ways to make ink, rather than by using the standard petroleum-based ink. Rising prices for petroleum and quarrels with OPEC countries were reasons they wanted to find a more reliable and cost efficient method of printing. After testing over 2,000 different vegetable oil formulations, researchers for the NAA came up with the solution of using soybean oil. In 1987, soybeans were tested by The Gazette from Iowa in a practical printing run. The test was successful. About one quarter of commercial printers in the United States now use soy ink.

The National Soy Ink Information Center was established in 1993 by the Iowa Soybean Association to promote research and use of soy ink. The center created the SoySeal mark used to identify products meeting basic requirements. The success of soy ink was judged to be sufficient to justify the closing of the National Soy Ink Information Center in 2005. Use of the SoySeal is now regulated by the American Soybean Association.

To make soy ink, soybean oil is slightly refined and then blended with pigment, resins, and waxes. Even though soybean oil is an edible vegetable oil, soy ink is not edible or 100% biodegradable because the pigments and other additives that are mixed with the oil are the same as those used in petroleum-based inks. Degradability studies conducted by Erhan and Bagby concluded that the pigment carrier in 100-percent soy ink degrades almost twice as completely as ink made from soy oil and petroleum resins, and more than four times as completely as standard petroleum inks. Soy ink is a helpful component in paper recycling because the soy ink can be removed more easily than regular ink from paper during the de-inking process.

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