Abstract: A copper phthalocyanine derivative having the formula: ##STR1## or a mixture thereof wherein CuPc represents the residue of a copper phthalocyanine molecule, Y is an alkyl or alkenyl residue each having from 8 to 22 carbon atoms, and each being unsubstituted or substituted by one or more hydroxy groups or being interrupted by one or more nitrogen atoms, or Y is an alkoxyaryl- or aralkyloxyaryl, or an alkyl-aralkyloxyaryl residue wherein the alkoxy-, aralkyloxy- or alkyl-aralkyloxy moiety contains from 7 to 22 carbon atoms, and n is an integer from 1 to 8, provides, when incorporated into a phthalocyanine pigment, a phthalocyanine pigment composition having excellent flocculation resistance, when incorporated into paint and printing media, which moreover exhibit improved flow.