Method of making hydroxygallium phthalocyanine type V photoconductive imaging members
US5482811A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 31, 1994 |
| Grant date | Jan 9, 1996 |
| Priority date | — |
| Expiry date | Oct 31, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03G5/0696
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A process for the preparation of hydroxygallium phthalocyanines which comprises hydrolyzing a gallium phthalocyanine precursor pigment by dissolving said hydroxygallium phthalocyanine in a strong acid and then reprecipitating the resulting dissolved pigment in basic aqueous media; removing any ionic species formed by washing with water, concentrating the resulting aqueous slurry comprised of water and hydroxygallium phthalocyanine to a wet cake; removing water from said slurry by azeotropic distillation with an organic solvent, and subjecting said resulting pigment slurry to mixing with the addition of a second solvent to cause the formation of said hydroxygallium phthalocyanine polymorphs.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.