Process for the production of β-form copper phthalocyanine pigment
Abstract
Abstract A process for the production of a beta -form copper phthalocyanine having a particle size of 0.005 to 0.2 mu m and an aspect ratio of 1 to 3, which comprises the following steps: a. dry-milling a crude copper phthalocyanine in a milling apparatus until the resultant dry-milled product has an alpha -crystal content of more than 45% by weight, wet-milling the resultant dry-milled product in the presence of a water-soluble inorganic salt and at least one organic liquid selected from the group consisting of water-soluble alkylene glycols having 2 to 3 carbon atoms and polyoxyalkylene glycols, wherein the inorganic salt is used in an amount that is 2 to 10 times, by weight, as large as that of the dry-milled copper phthalocyanine, and wherein the organic liquid is used in an amount that is 0.1 to 2 times, by weight, as large as that of the dry-milled copper phthalocyanine, and c. removing the inorganic salt and the organic liquid from the resultant wet-milled product.
Inventors
- 👤 Yusaku Ide
- 👤 Toshimitsu Ikegaya
- 👤 Michichika Hikosaka
Bibliographic Details
Claims Analysis
Total Claims: 6References Cited (Backward Citations)
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