Novel digital printing ink-jet inks with “antifraud markers” used as additives

Two stilbene derivatives, Kahablanc APU (C.I Fluorescent Brightener 220) and Kahablanc BA (C.I Fluorescent Brightener 113) were used as possible “antifraudmarkers”. These were added in several amounts in water-based disperse ink-jetinks. The surface tension, pH, viscosity and conductivity of the formulations prepared were monitored over a period of 90 days in order to estimate the ink stability and the compatibility of the “antifraud” active agents with the ink constituents. The inks were used for ink-jetprinting of polyester and polyamide samples. Fastness and colour properties of the samples were measured. Qualitative and quantitative determination of the stilbene derivatives extracted from the printed samples was made and a simple spectrophotometrical method for their detection was proposed