Inventors:
Herman Gerson - New York NY
John Francis Santimauro - Wyckoff NJ
Lawrence Robert Lerner - Livingston NJ
Assignee:
Harmon Colors Corporation - Haledon NJ
International Classification:
C09B 4800
Abstract:
A process is described for making quinarcridone and its derivatives, useful as organic pigments, wherein a 2,5-diarylaminoterephthalic acid and an acid catalyst are heated in a two phase liquid system, comprising ethylene glycol and an organic liquid which is immiscible with water and ethylene glycol, wherein the ethylene glycol is present in an amount of about 0. 25 to 4 parts by weight per part of 2,5-diarylaminoterephthalic acid and the organic liquid is present in an amount of at least about 2 parts by weight per part of ethylene glycol, at a temperature sufficient to remove by-product water from the liquid system by vaporization.