| 摘要 |
PROBLEM TO BE SOLVED: To provide a heat-resistant multiaxial stitch base material which does not cause the heat-shrinking or the heat-melting of a stitch yarn even when exposed to a high-temperature environment in a preform production step and a fabrication step, or in an FRP product, and which can prevent the formation of a defective product due to water absorption.SOLUTION: In a multiaxial stitch base material 1, multiple reinforcing fiber sheets 3 obtained by arranging reinforcing fiber yarns parallel to each other are stacked each in a different orientation direction, and the sheets are sewn together to be integrated by using a stitch yarn 2 passing through the sheets. In the heat-resistant multiaxial stitch base material 1, there is adopted technical means such that the stitch yarn 2 is made to have a fineness of 100-500 dtex, and is made as a twisted yarn formed of glass fiber yarns having breaking strain energy in an amount of 30 MJ/mor more. The twisted yarn constituting the stitch yarn is a two-ply yarn or a three-ply yarn in which, to two or three single yarns with primary twists imparted thereto, final twists in a direction opposite to that of the primary twists and in 60-90% of the number of the primary twists are imparted. Accordingly, the heat-resistant multiaxial stitch base material is provided.SELECTED DRAWING: Figure 1 |
