Patent ID: 7601210

Claim:
A method of producing an ink jet ink, the ink jet ink comprising water, coloring materials, and a water-soluble organic solvent, wherein the coloring materials comprise at least one dye selected from the group consisting of C.I. Direct Blue 199, C.I. Direct Blue 86, and C.I. Acid Blue 9, and a pigment having a copper phthalocyanine skeleton, wherein the water-soluble organic solvent comprises a poor medium for the pigment having the copper phthalocyanine skeleton, and wherein a content of the pigment having the copper phthalocyanine skeleton in the ink is less than 1 mass % with respect to a total mass of the ink jet ink, said method comprising the step of injecting an ink comprising at least one dye selected from the group consisting of C.I. Direct Blue 199, C.I. Direct Blue 86, and C.I. Acid Blue 9 as a coloring material into an ink cartridge storing an ink which comprises a pigment having a copper phthalocyanine skeleton and a poor medium for the pigment.