John S. Zambounis

Latent pigments activated by heat

Organic pigments are used as colourants in paints, plastics, printing inks and in the electronics industries. They can be distinguished from dyes in that they are insoluble. Whereas dyes readily dissolve to give homogeneous coloration, the application of organic pigments frequently requires a time- and energy-consuming dispersion step. Here we report a method for converting a pigment into a suitable precursor, a ‘latent’ pigment. Like a dye, the latent pigment is readily soluble or homogeneously dispersible in the application medium, and on subsequent thermal treatment it can be transformed in situ to the parent pigment.