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:
Feb. 14, 1984
Filed:
Jan. 06, 1982
Applicant:
Inventors:
Helmut Hoch, Wachenheim, DE;
Heinrich Hiller, Wachenheim, DE;
Assignee:
BASF Aktiengesellschaft, Ludwigshafen, DE;
Primary Examiner:
Int. Cl.
CPC ...
C07D / ; C09B / ;
U.S. Cl.
CPC ...
549 56 ;
Abstract
4,4',7,7'-Tetrachlorothioindigo pigments of high color strength are prepared by oxidizing 3-hydroxy-4,7-dichlorothionaphthene or a mixture of tetrachlorothioindigo and hydroxydichlorothionaphthene in aqueous alkaline suspension with a salt of a nitro-aromatic sulfonic acid, in the presence of a high-boiling, water-immiscible or only slightly water-miscible aromatic liquid, at from 40.degree. to 100.degree. C., and heating the organic suspension to 110.degree.-180.degree. C. Pigmentary forms of tetrachlorothioindigo are isolated which give deep colorations of high brilliance when reduced with white pigments.