Patents Assigned to West Fraser Timber Co. Ltd.
  • Method of bleaching with formamidine sulfinic acid using a reducing agent to eliminate residual peroxide
    Patent number: 6428653
    Abstract: A process for final bleaching cellulose-containing pulp which has been subjected to previous bleaching with a peroxide compound. The process involves the sequential steps of exposing the pulp to an amount of a reducing agent in order to eliminate residual peroxide compound from the pulp and then final bleaching the pulp by exposing the pulp to an amount of formamidine sulfinic acid.
    Type: Grant
    Filed: December 4, 2000
    Date of Patent: August 6, 2002
    Assignee: West Fraser Timber Co. Ltd.
    Inventors: Richard C. Denton, Gorgen Akerlund