Copper phthalocyanine
chemical compound
Copper phthalocyanine (CuPc), also called phthalocyanine blue, phthalo blue and many other names, is a bright, crystalline, synthetic blue pigment from the group of dyes based on phthalocyanines. Its brilliant blue is frequently used in paints and dyes. It is highly valued for its superior properties such as light fastness, tinting strength, covering power and resistance to the effects of alkalis and acids. It has the appearance of a blue powder, insoluble in most solvents including water.
Synonyms and trade names
The substance, IUPAC name (29H,31H-phthalocyaninato(2−)-N29,N30,N31,N32)copper(II), is known by many names such as monastral blue, phthalo blue, helio blue, thalo blue, Winsor blue, phthalocyanine blue, C.I. Pigment Blue 15:2, copper phthalocyanine blue, copper tetrabenzoporphyrazine, Cu-phthaloblue, P.B.15.2, C.I. 74160, and British Rail Blue. Numerous other trade names and synonyms exist. The abbreviation "CuPc" is also used.
Structure, reactivity and properties
Copper phthalocyanine is a complex of copper(II) with the conjugate base of phthalocyanine, i.e. Cu2+Pc2−. The description is analogous to that for copper porphyrins, which are also formally derived by double deprotonation of porphyrins.
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