Patent ID: 7641725

Claim:
A mixture of compounds of Formula (I) and salts thereof: wherein: M is 2H, Si, a metal, an oxymetal group, a hydroxymetal group or a halometal group; Pc represents a phthalocyanine nucleus of formula; R 1 is H or optionally substituted C 1-4 alkyl; R 2 is optionally substituted alkyl or optionally substituted heterocyclyl; R 3 is H or optionally substituted C 1-4 alkyl; R 4 is optionally substituted hydrocarbyl; w is 0.1 to 3.7; x is 0.1 to 3.7; y is 0.1 to 3.7; z is 0.1 to 3.7; and provided that the substituents represented by y and z are different.