Patent · US Expired

Preparation of water-soluble copolymers containing vinylamine units, and their use as wet strength agents and dry strength agents for paper

US4880497A · kind A · utility

53Cited by

3References

8Claims

0Family size

Assignee

BASF SE

Inventors

Sigberg Pfohl · Speyer, DE
Michael Kroener · Mannheim, DE
Heinrich Hartmann · Schifferstadt, DE
Walter Denzinger · Speyer, DE

Key dates

Filing date	Apr 29, 1988
Grant date	Nov 14, 1989
Priority date	—
Expiry date	Apr 29, 2008

Classification

Technology area (CPC D)Textiles; Paper
CPC primaryD21H21/18
WIPO fieldTextile and paper machines
WIPO sectorMechanical engineering

Abstract

Water-soluble copolymers containing copolymerized vinylamine units are prepared by copolymerizing (a) from 95 to 10 mol % of N-vinylformamide and (b) from 5 to 90 mol % of an ethylenically unsaturated monomer from the group consisting of vinyl acetate, vinyl propionate, C.sub.1 -C.sub.4 -alkyl vinyl ethers, the esters, nitriles and amides of acrylic acid and methacrylic acid and N-vinylpyrrolidone, and then eliminating from 30 to 100 mol % of the formyl groups from the copolymer. Preferred copolymers are copolymers of N-vinylformamide and vinyl acetate, in which from 30 to 100 mol % of the monomer units are hydrolyzed. The copolymers are used in papermaking to increase the dry strength and wet strength of the paper.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.