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:
Apr. 30, 1991
Filed:
May. 19, 1989
Applicant:
Inventors:
V R Parthasarathy, Raleigh, NC (US);
Meenaksi Sundaram, Raleigh, NC (US);
Hasan Jameel, Raleigh, NC (US);
Josef S Gratzl, Cary, NC (US);
Ronald J Klein, Edison, NJ (US);
Assignees:
FMC Corporation, Philadelphia, PA (US);
North Carolina State University, Raleigh, NC (US);
Attorneys:
Primary Examiner:
Int. Cl.
CPC ...
D21C / ; D21C / ; D21C / ;
U.S. Cl.
CPC ...
162 56 ; 162 65 ; 162 78 ;
Abstract
A process is provided for a two-stage oxygen delignification of chemical pulp in which 0.01% to 1% hydrogen peroxide is incorporated into the first and, optionally the second stage. The invention is particularly suitable when the pulp is subsequently bleached with at least one chlorine dioxide stage and at least one hydrogen peroxide stage.