| 摘要 |
752,381. Bleaching cellulosic textiles. DEUTSCHE GOLD-UND SILBER-SCHEIDEANSTALT VORM. ROESSLER. April 1, 1954 [April 21, 1953], No. 9620/54. Addition to 738,903. Class 15(2) Cellulcsic textile material in band form is repeatedly and thoroughly penetrated with a solution, which may be activated, of an alkali or alkaline earth chlorite which is cold or only moderately heated, e.g. up -to 60‹C., for a relatively short period, e.g. 3 to 25 minutes, excess liquor is removed by squeezing and the material is then heated to a temperature of up to 100‹C. by steam treatment and immediately thereafter passed into a closed, heat-insulated chamber in which it is laid in regular folds and through which the folded material travels continuously, each individual fold remaining in the chamber for from 5 to 15 times as long as that portion of the material remained in the chlorite bath. The closed, heat-insulated chamber may be a J-box through which the transit time of the material may be from 1.5 to 2.5 hours. The bleaching solution may contain sodium chlorite, tetrasodium pyrophosphate and sulphonated castor oil and may be at a temperature of 25‹C. The material may be cotton. |
