Use of mixed-crystal pigments of the quinacridone series in electrophotographic toners and developers, powder coatings and inkjet inks

US6251553A · kind A · utility

Assignee

• Clariant Corporation · DE

Inventors

• Ruediger Baur · Niedernhausen, DE
• Manfred Urban · Wiesbaden, DE
• Hans-Tobias Macholdt · Darmstadt, DE
• Dieter Schnaitmann · Eppstein, DE
• Martin Boehmer · Neu-Anspach, DE

Key dates

• Filing date: Nov 23, 1999
• Grant date: Jun 26, 2001
• Expiry date: Nov 23, 2019

Classification

• Technology area (CPC G): Physics
• CPC primary: G03G9/122
• WIPO field: Basic materials chemistry
• WIPO sector: Chemistry

Abstract

The use of mixed-crystal pigments of the quinacridone series consisting of PA1 a) from 85 to 99% by weight of unsubstituted .beta.-phase quinacridone of the formula (I) ##STR1## PA2 in which R.sup.1 and R.sup.2 are hydrogen atoms, and PA1 b) from 1 to 15% by weight of one or more substituted quinacridones of the formula (I) in which the substituents R.sup.1 and R.sup.2 are identical or different and are chlorine, bromine or fluorine atoms or PA2 C.sub.1 -C.sub.4 -alkyl, C.sub.1 -C.sub.4 -alkoxy or carboxamido groups, which can be substituted by C.sub.1 -C.sub.6 -alkyl groups, and R.sup.1 can additionally be hydrogen, as colorants in electrophotographic toners and developers, powder coating materials, inkjet inks, electret fibers, and color filters.