Treatment of water-resistant acetalized polyvinyl alcohol fibers with alkali metal boro hydride for improved thermal stability

摘要

Fibres of polyvinyl alcohol, copolymers of vinyl alcohol, and acetol derivatives thereof are prevented from discolouring during heat treatment, particularly during ironing, by treating with an alkaline borohydride, such as sodium or potassium borohydride. In Example 3, vinylon fibres are immersed in a 0,1% aqueous solution of sodium borohydride for 5 hours at room temperature, then dipped in acetic acid solution and washed with water and dried. In Examples 4 and 5 the vinylon fibres are bleached with bleaching powder or hydrogen peroxide respectively, and then immersed in a borohydride solution.