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:
Jan. 19, 1982
Filed:
Jan. 14, 1980
Applicant:
Inventors:
Sven G Akerlund, Sollentuna, SE;
Jan-Erik Hook, Lilla Edet, SE;
Assignees:
Sunds Defibrator AB, Stockholm, SE;
Eka AB, Stockholm, SE;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
D21B / ;
U.S. Cl.
CPC ...
162 23 ; 162 26 ; 162 78 ; 162 80 ; 162 90 ;
Abstract
A method of producing peroxide bleached pulp. Lignocellulose fiber material is impregnated with an aqueous silicate solution containing a sequestering agent. The impregnated lignocellulose is preheated with saturated steam at a temperature corresponding to the defibrating temperature to precipitate silic acid on and in the fibers. The preheated fiber mass is defibrated between two grinding disc in an atmosphere of saturated steam at a temperature of 100.degree.-170.degree. C. Alkaline peroxide solution free of silicate is introduced into the grinding space.