Mitsubishi Chemical Industries Limited

Yoshio Kimura

Kiyoshi Himeno

Kiyoharu Urakawa

Kiyotomi Kosai

Yasuhito Goto

Haruki Uchida

Kenzo Ban

Methoxyanthraquinones are produced from the corresponding nitroanthraquinones by reacting a nitroanthraquinone with methanol and an alkali in a reaction medium chiefly comprising methanol at a temperature of 50.degree.-130.degree. C under atmospheric or superatmospheric pressure in the presence of molecular oxygen wherein the dissolved oxygen concentration of the reaction medium is maintained at a value of at least 1 ppm.

Process for producing high purity methoxyanthraquinones

An oxyquinophthalone coloring material having the general formula ##SPC1## Wherein X represents chlorine or bromine atom and Y.sub.1, Y.sub.2 and Y.sub.3 represent respectively hydrogen, chlorine, bromine, methyl, ethyl, methoxy or ethoxy group, at least one of Y.sub.1, Y.sub.2 and Y.sub.3 being chlorine or bromine and one of Y.sub.1, Y.sub.2 and Y.sub.3 being methyl, ethyl, methoxy and ethoxy group.

Oxyquinophthalone coloring material

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Kitakyushu, Japan

Yoshio Kimura