Patent ID: 7520927
Filing Date: 2009-04-21
Classification: B41J,C09B,C09D

Abstract:
1. A liquid ink for ink jet comprising: water; a coloring material; 1,5-pentanediol; and a humectant, wherein the coloring material comprises at least one compound represented by the following formula (1): where M's each represent an alkali metal or ammonium, l=0 to 2, m=1 to 3, and n=1 to 3, provided that l+m+n=3 to 4, and a substitution position of a substituent comprises 4- or 4′-position; and wherein the liquid ink for ink jet gels or solidifies if it is left under an environment having a temperature of 25° C. and a humidity of 50% RH until substantially no change in weight occurs, and the gelled or solidified ink for ink jet liquefies after being left under an environment having a temperature of 30° C. and a humidity of 50% RH for 24 hours.