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. 27, 1991
Filed:
Jul. 20, 1990
Thomas Staffel, Hurth, DE;
Renate Adrian, Hurth, DE;
Hoechst Aktiengesellschaft, Frankfurt am Main, DE;
Abstract
A process for producing essentially water-insoluble, chain-type ammonium polyphosphates of the general formula (NH.sub.4 PO.sub.3).sub.n, in which n is a number from 10 to 1,000, whose 20% by weight aqueous suspension prepared at 60.degree. C. has a viscosity of less than 100 mPa.s at 20.degree. C., is indicated, which comprises allowing a reaction mixture of ammonium orthophosphate and phosphorus pentoxide to react fully at a high mixing intensity in a crumbly phase at a temperature from 100.degree. to 300.degree. C. over a period of from 10 to 60 minutes and then heat-treating the reaction material in a known manner over a period of from 50 to 200 minutes at a temperature from 200.degree. to 300.degree. C. under an ammonia atmosphere. Advantageously, the reaction is carried out in a kneader.