Copper Phthalocyanine (CPC) pigments, by virtue of their exceptionally brilliant shade, high tinctorial strength, low cost and outstanding fastness properties, have been ruling the colorant industry ever since their commercial introduction in 1935. They are about to complete 70 years of meritorious service as an unchallenged leader of various types of blue and green pigments. In this context it is appropriate to present a brief review on some aspects related to their origin, development, mechanisms of formation and other finer details pertaining to their various properties.
In the beginning of the 20th century, commercially available blue pigments consisted mainly of Ultramarine blue, Prussian blue, Indigo derivatives and some azo derivatives. Unfortunately none of these had the desired qualities demanded by the colour industry. Most of these pigments had poor chemical resistance, unsatisfactory acid and/or alkali resistance, insufficient light fastness and poor sublimation fastness.