Dainichiseika Color & Chemicals Mfg. Co., Ltd.

Masahiko Aoba

Shotoku Takami

Koji Tsuchiya

Shigeru Takarada

Keiji Nakajima

Kazutaka Aoki

Takeshi Tamaki

Yukio Kanbara

Kenjiro Matsumoto

An object is to overcome the drawbacks of conventional blue phthalocyanine pigments upon the formation of images, and to develop a blue pigment that can satisfactorily exhibit a greenish blue color high in chroma and excellent in colorfulness, brightness, dispersibility, hue, tinting power and the like and that is applicable to various image recording methods. The object can be achieved by a greenish blue pigment, which exhibits a greenish blue hue of high chroma and contains a pigment represented by the following formula (I): wherein the number, m, of substituent phthalimidomethyl group(s) is in a range of 1.0&#x2266;m&#x2266;5.0, and the number, n, of a substituent sulfonic group R1 is in a range of 0.05&#x2266;n&#x2266;1.0.

Greenish blue pigment, colorant composition containing said pigment, and image recording material

A composite pigment of a bluish green color comprises copper phthalocyanine and aluminum phthalocyanine which are preferably in the form of a mixture or solid solution. The composite pigment can be produced by mixing copper phthalocyanine and aluminum phthalocyanine into a mixture and then converting said mixture into a pigment form. A coloring composition comprises at least a resin and a pigment which comprises copper phthalocyanine and aluminum phthalocyanine. The coloring composition can be produced by mixing copper phthalocyanine and aluminum phthalocyanine which have been independently comminuted, into a composite pigment, and then kneading the pigment and a resin such that the pigment is dispersed in the resin. An image recording substance is produced using the coloring composition. The image recording substance can be a dry developer of a fine powder form or a wet developer of a liquid form, an ink-jet ink, or a thermal transfer ink ribbon with the coloring composition coated on a film-shaped or sheet-shaped base material.

Composite pigments, coloring compositions, and image recording substances

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Tokyo, Japan

Masahiko Aoba