| abstract |
Disclosed is a pigment derivative, characterized by being a dye derivative obtained by linking the molecule of a water-insoluble dye (A) and the residue of a compound (C) to each other through an alkylene group formed by reacting the dye (A) with an aldehyde compound (B). By appropriately selecting the compound (C) from hydrocarbon compounds (C-1) having a methane group (-CH=) with a hydrogen group which is susceptible to substitution and amino compounds (C-2) having a reactive amino group, a deeper color effect than the color of an existing dye is brought about. Further, by using a pigment derivative effective as an additive for suppressing the crystal transfer or crystal growth of a pigment and also using the dye derivative, a colorant which has the above-mentioned effect, and also achieves a decrease in the viscosity of a pigment dispersion and has improved properties such as dispersion stability and long-term storage stability is realized. By using this colorant, a useful coloring method and a colored article are provided. |