Application of Radiotracer Techniques to the Study of Penetration of Ink Components Through Various Substrates.

Current Food and Drug Administration regulations include printing ink components as potential food additives when used on food packaging materials. As a result, the radiotracer experiments described here were devised to measure quantitatively minute amounts of penetration through polyethylene and paper-board as well as migration from paper and textile container materials. The tracer used was carbon-14 labeled oleic acid that represented a mobile and relatively low molecular weight printing ink ingredient. Also described in this presentation is a radiotracer method for the determination of penetration rates by a carbon-14 tagged vehicle into the surface of several different printing stocks.