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:
Apr. 04, 1989
Filed:
Feb. 12, 1988
Applicant:
Inventors:
Hans-Juergen Degen, Lorsch, DE;
Sigberg Pfohl, Speyer, DE;
Volkmar Weberndoerfer, Mannheim, DE;
Gerd Rehmer, Bobenheim-Roxheim, DE;
Michael Kroener, Mannheim, DE;
Andreas Stange, Mannheim, DE;
Assignee:
BASF Aktiengesellschaft, Ludwigshafen, DE;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
D21D / ;
U.S. Cl.
CPC ...
1621682 ; 1621683 ; 1621684 ; 1621685 ; 162175 ;
Abstract
Paper and paperboard of high dry strength are produced by adding a dry strength enhancer to the paper stock and dewatering the paper stock with sheet formation by using as the dry strength enhancer a mixture of a cationic polymer which contains as characteristic monomers copolymerized units of