POROUS COMPOSITE SHEET FOR PREPREG AND PREPREG FOR WIRING BOARD

摘要

PROBLEM TO BE SOLVED: To provide a porous composite sheet for prepregs enabling coefficient of linear thermal expansion to be markedly improved not only in the direction of the board plane but also in the direction perpendicular thereto, and having sufficiently high mechanical strength as well, and to provide a prepreg for a wiring board using the above sheet. SOLUTION: This porous composite sheet for prepregs is such that a porous phase comprising an aromatic polyamide is filled among the fibers of a sheet- like fiber assembly comprising aromatic polyamide fibers.