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:
Jun. 16, 1998
Filed:
Feb. 25, 1997
Applicant:
Inventor:
Jianxin Chen, North Vancouver, CA;
Assignee:
Pulp and Paper Research Institute of Canada, Quebec, CA;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
D21C / ;
U.S. Cl.
CPC ...
162 65 ; 162 72 ; 162 78 ;
Abstract
A process of delignifying and bleaching a chemical wood pulp with hydrogen peroxide and dicyandiamide as an activator provides a higher degree of delignification and brightness of the pulp and overcomes problems of fibre degradation. The process comprises adding hydrogen peroxide and dicyandiamide as a bleaching activator to a chemical wood pulp slurry under alkaline conditions.