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. 02, 1983
Filed:
Mar. 29, 1982
Lothar Brandt, Wiesbaden, DE;
Arno Holst, Wiesbaden, DE;
Hoechst Aktiengesellschaft, Frankfurt am Main, DE;
Abstract
The application discloses a gel-forming composition based on (a) water, (b) a water-soluble cellulose mixed ether having at least one nonionic substituent from the group comprising hydroxyalkyl and alkyl and at least one anionic phosphorus-containing substituent, and (c) a salt containing a cation which is at least divalent. The phosphorus-containing substituent is a phosphonoalkyl group or a p-alkylphosphinoalkyl group. The application also relates to a process for the preparation of a gel from this composition, to the reversible reversing of the gel by the addition of an agent which complexes the cation, e.g. in the case of Al.sup.3+ ions, Fe.sup.3+ ions, Zr.sup.4+ ions or ZrO.sup.2+ ions, by means of an amount of fluoride ions, and to the use of this gel-forming compostion in the secondary production of petroleum.