Patent ID: 6918955
Filing Date: 2005-07-19
Classification: C09D

Abstract:
1. An ink-jet recording liquid, comprising: an aqueous medium containing a surfactant, a pigment and a dye, wherein (1) at least some of the dye molecules reversibly adsorb on pigment molecules without the involvement of a chemical reaction therebetween, thereby forming pigment/adsorbed dye entities; (2) the dye that is reversibly adsorbed on the pigment without involving a chemical reaction comprises a dye having a dye adsorption shown by the following formula (1) of 0.02 g/g or more, wherein the dye adsorption ratio is a value that is determined by analyzing (i) a supernatant liquid obtained by removing solid components from a dispersion prepared by mixing the pigment (4.1 g) and the dye (0.4 g) in the absence of a surfactant in water, and (ii) an aqueous solution of the dye (0.4 g), by high performance liquid chromatography whereby the concentration of dye in each of (i) and (ii) is determined from the peak areas of the two chromatographs obtained and the ratio of dye concentration of(i) to (ii) is determined; and (3) the surfactant comprises a combination of a nonionic surfactant and an anionic surfactant.