PREPREG AND LAMINATE WITH UNIFORM DIELECTRIC PROPERTY

To provide a prepreg for a high frequency substrate, a metal laminate and a printed wiring board manufactured therewith that solve the distortion problem by eliminating a gap between the dielectric constant of a matrix and the dielectric constant of a reinforcing material.SOLUTION: In a prepreg 10 including a partially cured resin-impregnated reinforcing material portion 14 and a free resin portion 12, the resin includes at least one kind of high dielectric constant material, when the dielectric constant of the free resin portion is DKw, and the dielectric constant of the resin-impregnated reinforcing material portion is DKWR, a high dielectric constant material is added to the resin in such an amount that DKWR and DKW do not differ more than (±)15%.SELECTED DRAWING: Figure 1 【課題】マトリックスの誘電率と強化材料の誘電率の間のギャップを取り除くことにより、ひずみの問題を解決する高周波基板用のプレプレグ、それを用いて製造される金属ラミネート及びプリント配線基板を提供する。【解決手段】部分的に硬化した樹脂含浸強化材料部分１４ならびに遊離の樹脂部分１２を含んでなるプレプレグ１０であって、樹脂は少なくとも１種の高誘電率材料を含み、遊離の樹脂部分の誘電率をＤＫｗ、樹脂含浸強化材料部分の誘電率をＤＫWRとすると、樹脂中に高誘電率材料を、ＤＫWRとＤＫWが（±）１５％より大きく異ならなくなる量添加したもの。【選択図】図１