| 摘要 |
Textiles and the like of cellulose materials or derivatives and artificial resins are bleached with aqueous solutions of alkaline or alkaline earth chlorites in the presence of hydrofluoric acid or one of its acid or neutral salts. In examples: (1) cotton is bleached in a bath containing sodium chlorite and ammonium difluoride; (2) flax tow is first treated with sodium hypochlorite and then with sodium chlorite and hydrofluoric acid; (3) genista fibre is treated as in (2); (4) cotton wool obtained by alkaline boiling of cotton linters followed by chlorinating with calcium hypochlorite, is heated with sodium chlorite and ammonium difluoride; (5) rayon is bleached in a bath containing sodium chlorite, hydrofluoric acid and a wetting agent; (6) wool having a colour of ferruginous origin is treated with sodium chlorite and ammonium difluoride; (7) cellulose pulp is bleached with sodium chlorite in the presence of hydrofluoric acid, and (8) cotton is bleached with sodium chlorite, hydrofluoric acid and sodium pyrophosphate. Specification 496,247 is referred to. |
