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:
Nov. 30, 2004
Filed:
Apr. 22, 2002
Applicant:
Inventors:
Yoshiya Izumi, Tokyo, JP;
Jun Sugiura, Kawasaki, JP;
Hitoshi Kagawa, Yokohama, JP;
Naoya Azumi, Chiba, JP;
Assignee:
OJI Paper Co., Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
D21C 9/147 ; D21C 1/100 ;
U.S. Cl.
CPC ...
D21C 9/147 ; D21C 1/100 ;
Abstract
Lignocellulose pulp is bleached by bleaching a pulp in aqueous alkali solution with oxygen and treating the pulp with a hemicellulase, while a liquid fraction delivered from the enzyme treatment step is separated from the hemicellulase treated reaction mixture, and subjected to a penetration treatment through a separation membrane, for example, reverse osmosis membrane, to separate a permeated fraction from a non-permeated fraction; the permeated fraction is fed to the alkali-oxygen bleaching (oxygen delignification) step and is used as a liquid medium of the bleaching system.