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. 08, 1993
Filed:
Apr. 16, 1991
Applicant:
Inventor:
Bruce F Griggs, Columbia, SC (US);
Assignee:
Union Camp Patent Holdings Inc., Wayen, NJ (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
D21C / ; D21C / ;
U.S. Cl.
CPC ...
162 19 ; 162 40 ; 162 56 ; 162 60 ; 162 65 ;
Abstract
Unbleached pulp is combined with an aqueous alkaline solution while in a state of low consistency to distribute a first amount of alkaline material substantially uniformly throughout the pulp. The consistency of the pulp is then increased to above about 18%, and the high consistency alkali containing pulp is then treated with oxygen to effect delignification. The total amount of alkaline material applied to the pulp is between 0.8 and 7% by weight of oven dry pulp. High strength, low lignin pulps are subsequently formed which may be further bleached to high brightness with reduced amounts of chemicals.