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. 19, 1978
Filed:
Sep. 22, 1976
Ludwig Gall, Frankenthal, DE;
Wolfgang Fabian, Wilhelmsfeld, DE;
BASF Aktiengesellschaft, Ludwigshafen, DE;
Abstract
A new pigmentary form of perylene-3,4,9,10-tetracarboxylic acid diimide of the formula ##STR1## which has a specific surface area (measured by the BET method) of from 10 to 35 m.sup.2 /g and a maximum in the particle size distribution at from 0.1 to 0.5 .mu.m, the proportion of particles between these sizes being at least 50% of the total distribution and the mean ratio of length to width being from 3:1 to 1:1. The pure shade of the new pigmentary form gives strongly yellowish red colorations which are very pure and very bright. The new pigmentary form also has a good hiding power, which is from 2 to 3 times as great as that of the pigmentary forms of the prior art.