| 摘要 |
PROBLEM TO BE SOLVED: To obtain a sizing agent for glass fibers, good in stability of a solution with time and combustibility and capable of forming a film excellent in coherency, smoothness and flexibility on the surfaces of the glass fibers, improving the frictional resistance in weaving, providing a uniform glass cloth without fuzzing and carrying out the incineration and removal of the sizing agent after weaving. SOLUTION: This sizing agent for glass fibers is obtained by using a water- soluble polyurethane, prepared by reacting 100 pts.wt. alkylene oxide adduct containing ethylene oxide or the ethylene oxide and propylene oxide added to a compound having active hydrogen with 1-30 pts.wt.ε-caprolactone and further reacting the resultant modified polyol with a polyisocyanate or reacting the modified polyol with the polyisocyanate in an amount so as to provide 0.5-1.5mol equiv. based on hydroxyl groups in the modified polyol. The weight - average molecular weight of the water-soluble polyurethane is 50,000-300,000. |
