phthalocyanine

Also called metal-free phthalocyanine. a blue-green pigment, C32H18N8, derived from phthalic anhydride.

any of the group of blue or green pigments produced by the interaction of metal-free phthalocyanine and a metal, especially copper: used chiefly in the manufacture of enamels, printing inks, and automotive finishes.

a cyclic blue-green organic pigment. Formula: (C 6 H 4 C 2 N) 4 N 4 H 4

any of a class of compounds derived by coordination of this compound with a metal atom. They are blue or green pigments used in printing inks, plastics, and enamels