The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 12, 1980
Filed:
Jan. 16, 1979
Helmut Hoch, Wachenheim, DE;
Heinrich Hiller, Wachenheim, DE;
BASF Aktiengesellschaft, Ludwigshafen, DE;
Abstract
A process for the preparation of transparent pigmentary forms, of high tinctorial strength, of perylene-3,4,9,10-tetracarboxylic acid bis-p-phenetidide and bis-p-chloroanilide, in which the diimide concerned is converted to the leuco compound, and the latter, with or without prior isolation, is then oxidized in aqueous suspension in the presence of surfactants or while exposed to shearing forces in the presence or absence of surfactants, after which the pigment is isolated. The pigments give highly transparent very pure colorations when used unreduced, while in white reductions they give very deep colorations with substantially more yellowish hues than those given by the prior art pigments.