PRELIMINARILY CURED PRODUCT, ROUGHENED PRELIMINARILY CURED PRODUCT, AND LAMINATE

摘要

Provided is a preliminarily cured product which is capable of reducing the surface roughness of a roughened surface of a roughened preliminarily cured product and which is capable of increasing the bonding strength between the cured product and a metal layer. A preliminarily cured product (1) of the present invention is obtained by having the curing of an epoxy resin material progress. The preliminarily cured product (1) has a first main surface (1a) and a second main surface (1b). The first main surface (1a) is a surface to be roughened. The epoxy resin material contains an epoxy resin, a curing agent and a silica (2). The silica (2) contains first small-diameter silica particles (2A) having particle diameters of 0.01 µm or more but less than 0.5 µm and second large-diameter silica particles (2B) having particle diameters of from 0.5 µm to 20 µm (inclusive). In the preliminarily cured product (1), the first small-diameter silica particles (2A) are unevenly distributed so as to gather on the first main surface (1a) side, while the second large-diameter silica particles (2B) are unevenly distributed so as to gather on the second main surface (1b) side.