| 摘要 |
PROBLEM TO BE SOLVED: To obtain a glass fiber capable of giving a FRTP excellent in mechanical strength and water resistance, even if an urethane resin is used as a film forming agent, and maintaining excellent sizing property, even if the coated quantity of a sizing agent is reduced, by applying the sizing agent containing a tetraborate on the glass to stick a specific quantity of the tetraborate on the glass fiber. SOLUTION: The sizing agent containing the tetraborate such as sodium tetraborate, potassium tetraborate, calcium tetraborate is applied on the glass fiber and the coating quantity of the tetraborate is controlled to 0.1-5 wt.%, preferably 0.05-4 wt.% to the glass fiber. As a result, the glass fiber excellent in adhesivity to a matrix resin is obtained. As the film forming agent of the sizing agent, any resin including the urethane resin can be used except for damaging the sizing property. And the matrix resin for the FRTP, a polyphenylene sulfide resin preferably gives remarkable effect. |
