Patent ID: 8945294
Filing Date: 2015-02-03
Classification: B23B,B41J,B82Y,C09D,Y10T

Abstract:
1. An ink composition comprising: organic pigment particles; wherein an organic pigment of the organic pigment particles is selected from the group consisting of α crystalline type metal free phthalocyanine, α crystalline type copper phthalocyanine, copper phthalocyanine modified by chlorine or bromine, quinacridone modified by methyl or chlorine, and diketopyrrolo pyrrole modified by methyl or chlorine; a hydrosoluble solvent; a dispersing agent; and water, wherein each of the organic pigment particles has a circularity of 2 nm or less, which is defined as a difference between radii of concentric circumscribing and inscribed circles of a contour of an image of each of the organic pigment particles taken by a transmission electron microscope when a gap between the concentric circumscribing circle and the inscribed circle is least, wherein the inscribed circle has a diameter of from 5 nm to less than 50 nm.