Seiko Epson Corporation

Shintaro Hama

Kiyomi Kumamoto

Tetsuya Aoyama

Tomohiro Aruga

Ryosuke Teramoto

Yuho Miyake

Hidehiko Komatsu

Yusuke Mizutaki

Yasuhiro Oki

Daisuke Sakuma

Kazuma Tsutsumi

An ink jet ink composition contains a color material, an organic solvent, and water. The ink jet ink composition contains N-hydroxyethylpyrrolidone and N-vinyl-2-pyrrolidone as the organic solvent.

Ink jet ink composition and recording method

An ink set includes a first ink containing the compound represented by formula (y-1) or its salt, a second ink containing one or two or more of the compound represented by formula (m-1) or its salt, the compound represented by formula (m-2) or its salt, a compound represented by formula (m-3) or its salt, and the compound represented by formula (m-4) or its salt, and a third ink containing one or two or more of a compound represented by formula (c-1) or its salt, the compound represented by formula (c-2) or its salt, the compound represented by formula (c-3) or its salt, a compound represented by formula (c-4) or its salt, and the compound represented by formula (c-5) or its salt. 

Ink set

An ink set includes a pigment ink, containing a pigment, and a dye ink containing the compound represented by formula (y-1) below or a salt thereof. 

An ink composition contains dyes A and B. Dye A has a width at a half height of the largest peak in the absorption spectrum between 380 nm and 780 nm that is 50 nm or less. Dye B has a corresponding width at the half height that is 70 nm or more. Dye A is present in an amount of 40% by mass or more and 90% by mass or less of the total mass of the dyes.

Ink composition, ink set, recording method, and ink jet recording apparatus

An ink jet recording ink set of this invention is an ink jet recording ink set containing a dye ink and a pigment ink, in which the dye ink contains a dye in a proportion of 1.4% by mass or more and 5.0% by mass or less based on the total mass of the ink, the pigment ink contains a pigment in a proportion of 4.0% by mass or more and 8.0% by mass or less based on the total mass of the ink, and, when the volume average particle diameter of the pigment ink is defined as &#x3a6;1 and the volume average particle diameter of a mixed liquid in which the dye ink and the pigment ink are mixed in equal amounts in terms of the mass ratio is defined as &#x3a6;2, the following expression (1) is satisfied,1.00&#x2264;&#x3a6;2/&#x3a6;1&#x2264;1.40&#x2003;&#x2003;(1).

Ink jet recording ink set and ink jet recording method

An ink composition at least contains a compound A having a hydroxy group and a compound B having an aldehyde group as polyoxyalkylene alkyl ether surfactants. The mass ratio of the compound B to the compound A is 0.5&#xd7;10to 30&#xd7;10.

Ink composition and recording method

An aqueous ink set for ink jet recording includes an aqueous pigment ink containing water and a pigment as a coloring agent and an aqueous dye ink containing water and a dye as a coloring agent, in which the concentration of the divalent metal ions of the pigment ink is 10 ppm or more, and the potassium ion concentration of the dye ink is 50 ppm or less.

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Shiojiri, Japan

Shintaro Hama