On the Post-cure Case (UV Inks)

Formulators also handle the tricky issue of pigment concentration. Pigment level plays a major role in the success of the finished product, as the pigment either absorbs or reflects the photons emitted by UV lamps. Akzo Nobel's Stendahl states, "Formulators must select photoinitiators that will absorb light at wavelengths not absorbed by the specific pigments." He further notes that with too great a pigment concentration, light simply cannot get through the ink film to the ink/substrate interface. Neither cure nor adhesion takes place.