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:
Aug. 10, 1993
Filed:
Nov. 13, 1991
Applicant:
Inventor:
Ronald C Naddeo, Kempton, PA (US);
Assignee:
Air Products and Chemicals, Inc., Allentown, PA (US);
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
D21C / ; D21C / ; D21C / ;
U.S. Cl.
CPC ...
162-5 ; 162-6 ; 162-8 ; 162 65 ; 162 66 ; 162 89 ;
Abstract
Secondary pulp is deinked and bleached by contacting the pulp simultaneously with oxygen, alkali, and a surfactant in a reaction zone followed by washing to recover a secondary fiber product. Simultaneous contacting with oxygen and surfactant yields higher pulp brightness than sequential contacting in oxygen bleaching and washing stages, and enhances bleachability in further bleaching stages.