Patent ID: 7544236

Claim:
A compound of Formula (1) in the free acid or salt form: wherein: M is 2H, Si, a metal, an oxymetal group, a hydroxymetal group or a halometal group; Pc represents a phthalocyanine nucleus of formula; each R 1 and R 2 independently is H, optionally substituted alkyl or optionally substituted aryl; each R 3 independently is optionally substituted alkyl or optionally substituted aryl; each n independently is 1 or 2; x is 0.5 to 2; y is 0.1 to 2.5; z is 0.1 to 2.5; and the sum (x+y+z) is 2.2 to 4, and wherein the substituents represented by —(SO 3 H) x —, —(SO 2 NR 1 R 2 ) y and —(S(O) n R 3 ) z are each attached to the phthalocyanine ring through β-positions.