Patent ID: 8079769

Claim:
An ink cartridge for an inkjet printer, said ink cartridge containing an aqueous ink formulation, said ink formulation comprising an IR-absorbing naphthalocyanine dye of formula (II): or a salt form thereof, wherein: M is Ga(A 1 ); A 1 is an axial ligand selected from the group consisting of: —OH, halogen, —OR 3 , —OC(O)R 4 or —O(CH 2 CH 2 O) e R e wherein e is an integer from 2 to 10 and R e is H, C 1-8 alkyl and C(O)C 1-8 alkyl; R 1 and R 2 may be the same or different and are selected from the group consisting of: hydrogen or C 1-12 alkoxy; R 3 is selected from the group consisting of: C 1-12 alkyl, C 5-12 aryl, C 5-12 arylalkyl and Si(R x )(R y )(R z ); R 4 is selected from the group consisting of C 1-12 alkyl, C 5-12 aryl and C 5-12 arylalkyl; and R x , R y and R z may be the same or different and are selected from the group consisting of: C 1-12 alkyl, C 5-12 aryl, C 5-12 arylalkyl, C 1-12 alkoxy, C 5-12 aryloxy and C 5-12 arylalkoxy; said formulation having a pH in the range of 4 to 6.5.