Patent ID: 8367750
Filing Date: 2013-02-05
Classification: B41J,C09D

Abstract:
1. A method of inhibiting a seeping out phenomenon of a polymer from an ejection orifice of an ink jet recording head, the method comprising: using an aqueous ink comprising (1) a polymer having hydroxyl groups, (2) a pigment, and (3) an aqueous medium which is a mixed solvent of water and at least one water-soluble organic solvent, wherein the water-soluble organic solvent comprises a polyhydric alcohol having a value of number of hydroxyl groups/number of carbon atoms in its molecule of 0.40 or less, wherein the polymer having hydroxyl groups is a polyvinyl alcohol type polymer that is a copolymer with a segment having hydroxyl groups and a segment having no hydroxyl group, wherein the pigment is dispersed in the aqueous medium by the polymer having hydroxyl groups, and wherein the ink after two weeks at room temperature in an ink cartridge, the ink cartridge communicating with an ink jet recording head having a plurality of nozzles, exhibits seeping out phenomenon on less than 1% of the plurality of nozzles of the ink jet recording head.