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:
Jan. 06, 1998
Filed:
Nov. 13, 1995
Rolf Kuropka, Bad Soden, DE;
Hoechst Aktiengesellschaft, , DE;
Abstract
Copolymers containing carboxyl groups in aqueous dispersion form or redispersible powder form and their water-soluble salts, based on ethylenically unsaturated and copolymerizable monomers, the macro-molecules of which contain at least 24% by weight of monomer units carrying carboxyl groups prepared, by emulsion copolymerization initiated by free radicals in the presence of polyvinyl alcohol (PVA) or polyvinylpyrrolidone (PVP) dissolved in the aqueous phase and isolation of the copolymers in aqueous dispersion form, and optionally subsequent removal of water by spray drying to obtain redispersible copolymer powders and processes for their preparation and their use as thickeners in aqueous formulations which copolymers, by conversion into their water-soluble salt forms, are useful as thickening agents having a surprisingly advantageous rheology-modifying action in aqueous systems.