Production of beta form pigmentary copper phthalocyanine
US5449774A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 1, 1991 |
| Grant date | Sep 12, 1995 |
| Priority date | — |
| Expiry date | Apr 1, 2011 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC09B67/0032
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
The present invention provides a process for producing beta-form pigmentary copper phthalocyanine comprising a) producing crude copper phthalocyanine by charging phthalic anhydride or phthalimide, urea, a copper compound and a catalyst, at a substantially continuous and uniform rate, into a reaction chamber containing dry, granular, pre-formed copper phthalocyanine, and removing the reaction product from the reaction chamber; and b) convening the crude copper phthalocyanine produced in step a) into pigmentary form, by milling it either in the dry state or in an aqueous medium; mixing the milled material with an aqueous emulsion comprising i) a liquid C.sub.6 -C.sub.20 amine which is insoluble in water or alkali but is soluble in acid and ii) a surfactant capable of emulsifying the liquid amine; rendering the resulting mixture acidic to thereby dissolve the amine; and finally separating the desired pigmentary copper phthalocyanine from the treatment mixture.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.