phthalocyanine

noun

• a greenish-blue crystalline dye of the porphyrin group.

  • Chemical formula: C₃₂H₁₈N₈
• [count noun] any of a large class of green or blue pigments and dyes which are chelate complexes of phthalocyanine or one of its derivatives with a metal (in particular, copper): [as modifier]:phthalocyanine blue