| 摘要 |
PROBLEM TO BE SOLVED: To provide liquid thermosetting resin compositions useful as compositions for permanently filling holes such as via holes and through-holes in printed-wiring boards such as multilayer boards and double-sided boards, and a method for permanently filling holes of printed-wiring boards by using the compositions. SOLUTION: A liquid thermosetting resin composition comprises (A) an epoxy resin which is liquid at room temperature, (B) a phenolic resin which is liquid at room temperature, (C) a curing catalyst, and (D) a filler, wherein the filler (D) contains a spherical filler and a crushed filler and preferably, the spherical filler comprises a spherical fine particle filler and a spherical coarse particle filler. Permanent filling of holes of a printed-wiring board can be carried out by filling this liquid thermosetting rein composition in the holes of a printed- wiring board, pre-curing the filled composition with heating and then, grinding the portion of the pre-cured composition overflowed from the surface of the holes to remove it, and further subjecting the pre-cured composition to proper curing with heating. |
