| 摘要 |
1,064,359. Polyvinyl alcohol filaments. SOC. RHODIACETA. April 2, 1965 [April 22, 1964], No. 14141/65. Heading B5B. Drawn polyvinyl alcohol yarns are continuously formalised by causing the yarns to travel under tension for less than three minutes through a bath at 80-90‹ C., containing 50% to 60% by weight of water, and sulphuric acid and formaldehyde in proportions represented by points within a substantially prismatoidal volume defined by the following points: The balance to 100 in each case is reckoned as between 2À9 and 3À26, the tension in the yarn anhydrous sodium sulphate. Preferably, the passing through the bath being from 0-25 residence time of the yarn in the bath is shorter g/tex to 1À25 g/tex. The drawn yarn may be than 30 seconds, especially 6-20 seconds, the washed with water or an aqueous solution of a bath temperature is 85‹ C., the proportion of wetting agent, e.g. a condensate of ethylene water in the treatment bath 57% and the molar oxide and lauryl alcohol and dried before passratio of sulphuric acid to formaldehyde is ing through the bath. |
