Phthalocyanine Green

Properties, chemistry and production

Phthalocyanine green is a pigment where most of the hydrogen atoms are replaced with . The strongly electronegative chlorine atoms influence the distribution of the electrons in the phthalocyanine structure, shifting its absorption spectrum. It is made by chlorination of the phthalocyanine blue as a melt of and , to which chlorine is introduced at elevated temperature.

The phthalo green molecules are highly stable. They are resistant to alkali, acids, , heat, and .

Due to its stability, phthalo green is used in , coatings, and many . In application it is transparent. The pigment is insoluble and has no tendency to migrate in the material. It is a standard pigment used in printing ink and packaging industry. It is also allowed in all except those used around the eyes, and is used in some .