| 摘要 |
PROBLEM TO BE SOLVED: To prevent release from occurring between layers of a board due to heat in a reflow furnace at the time of mounting a component when a laminate obtained by thermally pressure molding a layer of synthetic resin fiber nonwoven fabric impregnated with thermosetting resin is used for the board of a printed circuit board. SOLUTION: In the laminate, a moisture diffusion coefficient of the laminate is et to 1.3×10<-8> cm<2> /sec or less. As synthetic resin fiver nonwoven fabric for constituting the laminate impregnated with thermosetting resin, aramid fiber nonwoven fabric is, for example, used. To reduce the coefficient, the thermosetting resin having cycloalkane or the like as part or entirety of a molecular skeleton is used. For example, cyclopentadiene epoxy resin or cyclopentadiene cyanate ester resin is used. When a glass transition temperature of the laminate is set to 150 deg.C or higher, warpage of the laminate can be reduced. |
