A mixture of compounds of Formula (1) 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; R1 is H or optionally substituted C1-4alkyl; R2 is optionally substituted alkyl or optionally substituted heterocyclyl; R3 is H or optionally substituted C1-4alkyl; R4 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 groups represented by y and z are different. Also compositions and inks, printing processes, printed material and ink-jet printer cartridges.