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:
Aug. 03, 1993
Filed:
Jan. 24, 1992
John G Smigo, Macungie, PA (US);
Robert K Pinschmidt, Allentown, PA (US);
Andrew F Nordquist, Whitehall, PA (US);
Timothy L Pickering, Radford, VA (US);
Air Products and Chemicals, Inc., Allentown, PA (US);
Abstract
Polyvinylaminals, optionally as the formed copolymer with polyvinyl hemiaminals, and polyvinyl acetals are added to a papermaking pulp slurry to improve the retention of fines in the final paper product. This polymer is provided by reacting a poly(vinylamine) which can be a homopolymer or a copolymer containing vinyl alcohol and vinyl amine units with a monoaldehyde. The aldehyde, such as butyraldehyde, modifies the structure of the polymer and increases its hydrophobicity. The use of these polymers in papermaking involving the recycle of waste papers provides notable advantages in fines retention because of the high level of fines which normally accompany such recycle paper waste.