Cured body and multilayered substrate

Abstract

Provided is a cured body that can enhance the adhesion between an insulating layer and a metal layer, and can reduce the surface roughness on a surface of the insulating layer. The cured body according to the present invention is a cured body of a resin composition that includes an epoxy compound, a curing agent, an inorganic filler, and a polyimide, in which the content of the inorganic filler is 30% by weight or more and 90% by weight or less in 100% by weight of the cured body, the cured body has a sea-island structure having a sea part and an island part, the island part has an average long diameter of 5 μm or less, and the island part contains the polyimide.

Dependencies are inferred from the claim text.