Patent ID: 7476270

Claim:
An ink-jet ink comprising: an aqueous liquid vehicle; at least 1% by weight colorant; and a black-to-color bleed control enhancing amount of magnesium sulfate or hydrate thereof; wherein said colorant comprises at least one phthalocyanine dye, said phthalocyanine dye being a cyan dye having the structure: wherein M is a hydrogen atom; a metal atom; or an oxide, hydroxide, or halide of the metal atom; P c is a phthalocyanine nucleus; R 1 and R 2 are independently a substituent selected from the group of —SOX 1 , —SO 2 X 1 , —SO 2 NX 2 X 3 , —SO 3 X 4 ; where X 1 , X 2 , X 3 , and X 4 are independently a hydrogen atom, a substituted or unsubstituted C 1 to C 7 alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heterocyclic group; wherein at least one of R 1 or R 2 has an ionic hydrophilic group as a substituent; and k and l are independently an integer ranging from 1 to 3, where the sum of k and l is 4.