Patent · US Expired

Process for preparing modified .beta.-quinacridone pigment

US5229515A · kind A · utility

12Cited by
12References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 7, 1991
Grant dateJul 20, 1993
Priority date
Expiry dateJun 7, 2011

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC09B67/0027
  • WIPO fieldBasic materials chemistry
  • WIPO sectorChemistry

Abstract

A process for preparing a modified beta quinacridone polytype having identified color space values which comprises the steps of dry pre-milling beta phase quinacridone, deaggregating the pre-milled product in an alcohol-base medium and ripening the deaggregated product in the presence of an oxidizing agent.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.