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:
Dec. 11, 2007
Filed:
Jul. 23, 2003
Rainer Blum, Mannheim, DE;
Ralf Hemel, Worms, DE;
Norbert Mahr, Limburgerhof, DE;
Rudolf Lorz, Lambsheim, DE;
Rainer Blum, Mannheim, DE;
Ralf Hemel, Worms, DE;
Norbert Mahr, Limburgerhof, DE;
Rudolf Lorz, Lambsheim, DE;
BASF Aktiengesellschaft, Ludwigshafen, DE;
Abstract
Paper, board and cardboard are produced by shearing the paper stock, adding a microparticle system comprising a cationic polymer and a finely divided inorganic component to the paper stock after the last shearing stage before the head box, draining the paper stock with sheet formation and drying the sheets, by a process in which cationic polyacrylamides, polymers containing vinylamine units and/or polydiallyldimethylammonium chloride having an average molar mass Mw of in each case at least 500 000 Dalton and a charge density of in each case not more than 4.0 meq/g are used as cationic polymers of the microparticle system.