Patent ID: 7276110

Claim:
An ink set having four kinds of aqueous inks composed of a cyan ink, a magenta ink, a yellow ink, and a black ink, wherein each ink the ink set comprises at least: water; a water-insoluble coloring material; and a plurality of water-soluble organic solvents including (a) a good medium or good mediums for the water-insoluble coloring material and (b) a poor medium or good mediums for the water-insoluble coloring material, wherein: in the cyan ink, the ratio B 1 /A 1 is 0.5 or more and 3.0 or less, when A 1 denotes the total content (mass %) of the good medium or good mediums in the cyan ink and B 1 denotes the total content (mass %) of the poor medium or poor mediums in the cyan ink; in the cyan ink, a water-soluble organic solvent showing a maximum Ka value out of respective Ka values of the plurality of water-soluble organic solvents as each determined by the Bristow method is the poor medium; and for each aqueous ink in the ink set other than the cyan ink, A and B satisfies the following expression (I), when A denotes the total content (mass %) of the good medium or good mediums in the aqueous ink and B denotes the total content (mass %) of the poor medium or poor mediums in the aqueous ink: ( B 1 /A 1 )/( B/A )<1 (I).