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:
Feb. 27, 2007
Filed:
Jul. 01, 2002
Applicants:
Rudolf Patt, Reinbek, DE;
Othar Kordsachia, Oststeinbek, DE;
Bjorn Rose, Hamburg, DE;
Inventors:
Assignee:
Voith Paper Fiber Systems GmbH KG, Ravenburg, DE;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
D21C 3/02 (2006.01); D21C 3/04 (2006.01); D21C 3/20 (2006.01);
U.S. Cl.
CPC ...
Abstract
The invention relates to a method for delignifying lignocellulosic raw materials by using sulfites in the presence of an alkaline component, especially sodium hydroxide or sodium carbonate or a mixture thereof in an aqueous solution at a high temperature and high pressure. The invention is characterized in that a first partial fragment of the alkaline component is added when the aqueous solution starts to decompose and in that at least a second partial fragment of the alkaline component is added only when delignification begins.