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. 01, 1986
Filed:
May. 14, 1985
Jean J Renard, Georgetown, SC (US);
Shyam S Bhattacharjee, Monroe, NY (US);
International Paper Company, New York, NY (US);
Abstract
Extraction of chlorine bleached kraft wood pulps with aqueous peracids at pH values of 7 or below, aqueous sulfites at pH values below 10 or with certain non-aqueous solvents provides extracted pulps having lower residual color and permits use of lesser quantities of alkali or chlorine dioxide in subsequent bleach steps to attain brightness and strength levels comparable to those attained with pulps treated by alkaline extraction at pH values of 10 or higher. At a comparable level of alkali and chlorine dioxide or hypochlorite application, extraction of chlorinated pulp with peracids provides bleached pulps with enhanced brightness.