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:
Jul. 29, 2003
Filed:
Jan. 12, 2000
Raymond Seltzer, New City, NY (US);
David Devore, Nyack, NY (US);
Glen T. Cunkle, Stamford, CT (US);
Cyril Heitner, Pierrefonds, CA;
John A. Schmidt, L'ile Bizard, CA;
Peter F. McGarry, L'ile Bizard, CA;
Jean-Pierre Wolf, Courtaman, CH;
Randall B. Nelson, Seattle, WA (US);
Ciba Specialty Chemicals Corporation, Tarrytown, NY (US);
Abstract
Chemical pulps or papers, especially kraft pulps or papers, which may still contain traces of lignin, have enhanced resistance to yellowing when they contain an effective stabilizing amount of a N,N-dialkylhydroxylamine, an ester, amide or thio substituted N,N-dialkylhydroxylamine or N,N-dibenzylhydroxylamine or an amminium salt thereof. This performance is often further enhanced by the presence of one or more coadditives selected from the group consisting of the UV absorbers, the polymeric inhibitors, the nitrones, the fluorescent whitening agents and metal chelating agents. Combinations of hydroxylamines or their salts, benzotriazole or benzophenone UV absorbers and a metal chelating agent are particularly effective. N,N-Diethylhydroxylamine and N,N-dibenzylhydroxylamine and their acid salts are surprisingly effective for this purpose.