Patent ID: 8529685

Claim:
A mixture of azaphthalocyanine compounds of Formula (1) and salts thereof: wherein: M is 2H, Cu or Ni; each P is independently CH or N; R 1 is H or optionally substituted C 1-4 alkyl; R 2 is H or optionally substituted C 1-8 alkyl; R 3 is H or optionally substituted hydrocarbyl; and R 4 is optionally substituted hydrocarbyl; or R 3 and R 4 together with the nitrogen atom to which they are attached represent an optionally substituted heterocyclic ring system; x is greater than 0 and less than 4; y is greater than 0 and less than 4; z is greater than 0 and less than 4; the sum of x+y+z is in the range of from 1 to 4 and provided that at least one P is N and that no more than two P groups in any one of the four component rings of the azaphthalocyanine nucleus are N.