摘要:
The present invention relates to a process for bleaching a cellulosic fibre material with a peroxide compound in an aqueous alkaline medium, comprising a bleaching step wherein: a) a first polymer (A) comprising a homopolymer of acrylic acid, methacrylic acid or maleic acid, or a copolymer of acrylic acid and/or methacrylic acid with an unsaturated dicarboxylic acid, and a solution of a second polymer (B) comprising a poly-alfa-hydroxyacrylic acid or a salt thereof, are added to a cellulosic fibre material, and b) thereafter adding a peroxide compound and an alkaline substance and carrying out the bleaching.
摘要:
The present invention relates to a process for bleaching a cellulosic fibre material with a peroxide compound in an aqueous alkaline medium, comprising a bleaching step wherein: a) a first polymer (A) comprising a homopolymer of acrylic acid, methacrylic acid or maleic acid, or a copolymer of acrylic acid and/or methacrylic acid with an unsaturated dicarboxylic acid, and a solution of a second polymer (B) comprising a poly-alpha-hydroxyacrylic acid or a salt thereof, are added to a cellulosic fibre material, and b) thereafter adding a peroxide compound and an alkaline substance and carrying out the bleaching.