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:
Sep. 06, 1988
Filed:
Jan. 20, 1988
Ernst Spietschka, Idstein, DE;
Helmut Troster, Konigstein, DE;
Hoechst Aktiengesellschaft, Frankfurt, DE;
Abstract
Process for preparing perylenetetracarbimide mix-crystal pigments in the crystal lattice of the .alpha.-modification of the N,N'-bis-3',5'-dimethylphenylperylenetetracarbimide of the formula (1) comprising essentially symmetrical N,N'-bis-3',5'-dimethylphenylperylenetetracarbimide of the formula (1) and at least one asymmetrically substituted diimide of the formula (2) in which R stands for methyl or ethyl ##STR1## by condensing 1 mole of perylenetetracarboxylic dianhydride with an excess of up to 30 moles of 3,5-dimethylaniline which contains in total 0.5-6 percent by weight of 4-ethoxyaniline, and their use for coloring organic polymers.