A polysiloxane-substituted quinacridone pigment is produced by a quinacridone pigment with an epoxy-terminated polysiloxane under conditions effective to cause the epoxy group on the polysiloxane to react with, and bond the polysiloxane to, the quinacridone pigment. The quinacridone pigment thus produced has the polysiloxane grouping bonded to one of the quinacridone nitrogen atoms via a hydrocarbon linking group, which bears a hydroxyl group on a carbon atom or to the quinacridone nitrogen atom. These quinacridone pigments are useful in electrophoretic displays.

The present disclosure relates to Quinacridone pigment and a process of preparation thereof. The Quinacridone pigment of the present disclosure exhibit higher chemical resistance to solvents, higher stability and higher resistance to acid and alkali.

The present disclosure relates to Quinacridone pigment and a process of preparation thereof. The Quinacridone pigment of the present disclosure exhibit higher chemical resistance to solvents, higher stability and higher resistance to acid and alkali.

There is provided a photoelectric conversion film including a quinacridone derivative represented by the following General formula and a subphthalocyanine derivative represented by the following General formula.

There is provided a photoelectric conversion film including a quinacridone derivative represented by the following General formula and a subphthalocyanine derivative represented by the following General formula.

A non-aqueous magenta ink composition for ink jet printing comprising a pigment, a pigment dispersant, a binder resin and an organic solvent, wherein the pigment comprises C.I. Pigment Red 254 and a red pigment having a quinacridone skeleton, and wherein a total amount of the C.I. Pigment Red 254 and the red pigment having a quinacridone skeleton is not less than 50% by mass in the pigment.

A non-aqueous magenta ink composition for ink jet printing comprising a pigment, a pigment dispersant, a binder resin and an organic solvent, wherein the pigment comprises C.I. Pigment Red 254 and a red pigment having a quinacridone skeleton, and wherein a total amount of the C.I. Pigment Red 254 and the red pigment having a quinacridone skeleton is not less than 50% by mass in the pigment.

An inkjet ink contains quinacridone pigment, pigment dispersion resin, and aqueous medium. The pigment dispersion resin contains absorbed resin that is absorbed by the quinacridone pigment and unabsorbed resin that is not absorbed by the quinacridone pigment. A ratio of the unabsorbed resin to the pigment dispersion resin is 50 weight percent or less. A sulfur concentration in the 10-fold diluent of supernatant liquid obtained by centrifuging the inkjet ink at 1,050,000 G for three hours is 0.4 ppm or more and 7.0 ppm or less. In an ultraviolet and visible ray absorption spectrum of the 25-fold diluent of the supernatant liquid, light absorbance at a predetermined peak is 0.7 or less. The predetermined peak is a maximum peak in a wavelength range of 400 nm or more and 490 nm or less.

An inkjet ink contains quinacridone pigment, pigment dispersion resin, and aqueous medium. The pigment dispersion resin contains absorbed resin that is absorbed by the quinacridone pigment and unabsorbed resin that is not absorbed by the quinacridone pigment. A ratio of the unabsorbed resin to the pigment dispersion resin is 50 weight percent or less. A sulfur concentration in the 10-fold diluent of supernatant liquid obtained by centrifuging the inkjet ink at 1,050,000 G for three hours is 0.4 ppm or more and 7.0 ppm or less. In an ultraviolet and visible ray absorption spectrum of the 25-fold diluent of the supernatant liquid, light absorbance at a predetermined peak is 0.7 or less. The predetermined peak is a maximum peak in a wavelength range of 400 nm or more and 490 nm or less.

The present invention provides [1] a process for producing a colored fine particle dispersion including the step of subjecting a dispersion including a pigment, a polymerizable monomer, a surfactant, a polymerization initiator and water to emulsion polymerization, the pigment being a pigment having a quinacridone skeleton; the surfactant being an anionic or nonionic surfactant; and the polymerization initiator including an anionic or nonionic azo-based compound, [2] a colored fine particle dispersion including colored fine particles having an average particle size of not less than 10 nm and not more than 300 nm, and [3] a process for producing a water-based ink for ink-jet printing, including the step of mixing the obtained colored fine particle dispersion and an organic solvent B.