DOUBLE-SIDED COPPER-CLAD LAMINATE FOR FORMING CAPACITOR LAYER AND MANUFACTURING METHOD THEREOF

摘要

PROBLEM TO BE SOLVED: To provide a double-sided copper-clad laminate for forming a capacitor layer which has an insulating layer showing excellent properties of withstand voltage without short-circuiting even when a voltage is impressed between copper leaf surfaces and beside not being destructed by a showering pressure on the occasion of etching. SOLUTION: The double-sided copper-clad laminate for forming the capacitor layer has a constitution wherein copper leaf layers being conductors are provided for outer layers on the opposite sides and a resin layer to be a dielectric is held between the copper leaf layers. The resin layer has a three-layer structure constituted of a thermosetting resin layer, a heat-resistant film layer and the thermosetting resin layer and the total thickness thereof is 25μm or below. The thermosetting resin layer is constituted of an epoxy resin material, while the heat-resistant film layer has dry characteristics of a Young's modulus of 300 kg/mm<2> or above, a tensile strength of 20 kg/mm<2> or above and a tensile modulus of elongation of 5% or above and has a softening temperature higher than a molding temperature of the thermosetting resin constituting the thermosetting resin layers positioned on the opposite sides. This film layer is constituted of the resin material having a relative dielectric constant of 2.5 or above.