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. 07, 1982
Filed:
Mar. 25, 1981
Bayer Aktiengesellschaft, Leverkusen, DE;
Abstract
Process for the isolation of 1-naphthylamine-4,6- or 1-naphthylamine-4,7-disulphonic acid from sulphonation mixtures obtained in the sulphonation of 1-naphthylamine-6- or 1-naphthylamine-7-sulphonic acid with sulphuric acid and sulphur trioxide, wherein the aqueous solutions or suspensions formed, when the sulphonation mixtures are introduced into water, are warmed to 80.degree. to 120.degree. C., optionally kept for a period of time at this temperature, are then cooled to temperatures below 70.degree. C., and the 1-naphthylamine-4,6- or 1-naphthylamine-4,7-disulphonic acid which has crystallized out is finally filtered off.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile