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.

Date of Patent:
Sep. 05, 1989

Filed:

Dec. 23, 1987
Applicant:
Inventors:

S Allen Grimsley, Portsmouth, VA (US);

James C Robinson, Chesapeake, VA (US);

Mark A Schroeder, Norfolk, VA (US);

Assignee:

Virginia Chemicals Inc., Portsmouth, VA (US);

Attorney:
Primary Examiner:
Int. Cl.
CPC ...
D21C / ;
U.S. Cl.
CPC ...
162 53 ; 162 71 ; 162 83 ; 162205 ; 162207 ; 162339 ;
Abstract

A method is described for increasing the brightness of reductively bleached high yield pulps, comprising bleaching the pulps with a reductive bleaching solution under anaerobic conditions and maintaining the bleached pulps under anaerobic conditions during all handling steps subsequent to bleaching, including paper formation, wet pressing, and drying of the paper formed therefrom. The bleached paper has higher brightness than the same paper produced under aerobic conditions, and the bleaching and handling-derived portion of this higher brightness is retained after storage of the finished paper.


Find Patent Forward Citations

Grimsley, S. (1989). Method of bleaching high yield pulp by using dithionite ion and (U.S. Patent No. 4863564). U.S. Patent and Trademark Office. https://idiyas.com/patent/badge/4863564

Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile

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