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. 11, 1986
Filed:
Oct. 01, 1984
Applicant:
Inventors:
Michael N Hull, Bardonia, NY (US);
Vacheslav M Yasnovsky, Orangeburg, NY (US);
Assignee:
International Paper Company, New York, NY (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
D21C / ;
U.S. Cl.
CPC ...
162 65 ; 162 79 ;
Abstract
Delignifying bleaching of lignocellulosic materials, particularly wood pulps already partly delignified by conventional alkaline pulping processes by electrochemically generated ferricyanide in the presence of an effective amount of molecular oxygen is disclosed. Attainment of low kappa numbers employing milder temperature and pressure conditions than are employed in conventional oxygen bleaching is made possible and the process may be substituted for at least a portion of the conventional chlorine based bleaching processes which are current industry standard practice for bleaching kraft pulps.