| 摘要 |
Wool fibres are bleached by immersing them in a dilute aqueous solution of hydrogen peroxide having a temperature not exceeding 50 DEG C. and a pH value between 6 and 10 for a time sufficient only to ensure thorough wetting of the wool, removing the wool, freeing from excess solution and heating to a temperature above 70 DEG C. but below 100 DEG C. The bleached wool is then preferably rinsed off to remove excess of hydrogen peroxide. In examples: (1) wool yarn is passed through an approximately 3 vol. hydrogen peroxide solution brought to pH 8 with sodium pyrophosphate, squeezed to retain its own weight of solution, heated to 90 DEG C. in an enclosed steam cabinet and then rinsed; (2) as in (1) but an optical bleaching compound is added to the rinsing bath; (3) wool fabric is passed through the peroxide bath as in (1), squeezed, heated to 80 DEG C. and then rinsed; and (4) wool yarn is passed through a 3 vol. hydrogen peroxide bath brought to pH 10 by adding sodium pyrophosphate and ammonia, squeezed, heated to 90 DEG C. and rinsed in water. |
