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:
Jul. 10, 1990
Filed:
Jul. 25, 1988
Applicant:
Inventors:
Andreas Stange, Mannheim, DE;
Hans-Juergen Degen, Lorsch, DE;
Werner Auhorn, Frankenthal, DE;
Volkmar Weberndoerfer, Mannheim, DE;
Michael Kroener, Mannheim, DE;
Heinrich Hartmann, Limburgerhof, DE;
Assignee:
BASF Aktiengesellschaft, Ludwigshafen, DE;
Primary Examiner:
Int. Cl.
CPC ...
D21H / ;
U.S. Cl.
CPC ...
1621682 ; 1621683 ; 1621684 ; 1621685 ; 162175 ;
Abstract
Paper, board, and cardboard having high dry strength are made by adding to the paper stock a dry strength agent which is obtainable by mixing enzymatically digested starch having a viscosity of from 20 to 2,000 mPa.s (measured in 7.5% strength aqueous solution at 45.degree. C.) and a cationic polymer which contains, as typical copolymerized monomers,