Sequential Bleaching of Mechanical Pulp with Sodium Hydrosulfite, 1994 Pulping Conference Proceedings
Alfred Cheung
The paper industry has a long history of using various chemicals in sequential steps to bleach mechanical pulp. In the past, it has not often been necessary to use this multi-stage principle in bleaching mechanical pulp. But now the need for higher brightness and lower bleach cost are beginning to favor this approach.
V-Brite bleach (Hoechst Celanese proprietary formulations containing sodium hydrosulfite) in sequential bleaching can attain a higher brightness level and provide greater flexibility when changing grades than a single stage of hydrosulfite bleach in mechanical pulp.
Sequential Bleaching of Mechanical Pulp with Sodium Hydrosulfite, 1994 Pulping Conference Proceeding