The present application provides a resin component, and a prepreg and a circuit material using the same. The resin component comprises unsaturated polyphenylene ether resin, polyolefin resin, terpene resin and an initiator. When the total weight of the unsaturated polyphenylene ether resin, polyolefin resin and terpene resin is defined as 100 parts by weight, the terpene resin is in an amount of 3-40 parts by weight. The polyolefin resin is one or a combination of at least two selected from the group consisting of unsaturated polybutadiene resin, SBS resin and styrene butadiene resin. The present application discloses that the resulting resin composition has good film-forming properties, adhesion and dielectric properties through the coordination of unsaturated polyphenylene ether resin, unsaturated polyphenylene ether resin, polyolefin resin and terpene resin, and the circuit boards using the same have higher interlayer peel strength and lower dielectric loss.

A resin composition, a prepreg, and a printed circuit board are provided. The resin composition is used to form a dielectric substrate layer. The resin composition includes a polymeric based material and fillers. Based on a total volume of the resin composition being 100 vol %, the resin composition includes 10 vol % to 60 vol % of the polymeric based material and 1 vol % to 80 vol % of the fillers. The fillers include hollow fillers, and the hollow fillers include a first hollow filler. A material of the first hollow filler is silicon dioxide.

Provided is a heat dissipation sheet capable of effectively enhancing adhesiveness and long-term insulation reliability. The heat dissipation sheet according to the present invention contains first inorganic particles having an aspect ratio of 2 or less, second inorganic particles having an aspect ratio of more than 2, and a binder resin. In this heat dissipation sheet, a content of the second inorganic particles is larger than a content of the first inorganic particles in 100% by volume of a region having a thickness of 15% on a first surface side in a thickness direction, and the content of the first inorganic particles in 100% by volume of the region having a thickness of 15% is larger than the content of the first inorganic particles in 100% by volume of a central region having a thickness of 70%.

A thermosetting resin composition contains an ethylene-propylene-diene copolymer (A), a terminal-modified polyphenylene ether compound (B), an inorganic filler (C), a styrene-based elastomer (D), and a fibrous filler (E).

Provided is a resin composition having excellent low water absorption, as well as a cured product, a prepreg, a metal foil-clad laminate, a resin sheet, and a printed wiring board. The resin composition contains a compound (A) represented by Formula (M1) and a compound (B) containing two or more unsaturated carbon-carbon double bonds, and in Formula (M1), A is a four- to six-membered alicyclic group:

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The thermosetting resin composition of the present invention includes an epoxy resin (A), a curing agent (B), and thermally conductive particles (C), in which the epoxy resin (A) includes a mesogen skeleton and has a softening point of 60° C. or lower, and a thermal conductivity λ.sub.200 of a cured product of the thermosetting resin composition at 200° C. is 12.0 W/(m.Math.K) or higher.

A printed circuit board is provided. The printed circuit board includes a substrate, an electrically conductive pattern layer, and a thermally conductive ink layer. The substrate includes a first surface. The electrically conductive pattern layer is located on the first surface and includes a contact portion and a wire portion. The thermally conductive ink layer covers the wire portion and exposes the contact portion. The thermally conductive ink layer includes a thermally conductive powder and a colloidal adhesive, where a weight percentage of the thermally conductive powder is less than 10%, and a weight percentage of the colloidal adhesive is higher than 80%. An electronic device including the printed circuit board is further provided.

A resin composition includes: a resin as Component (A); and an inorganic filler as Component (B). The Component (B) includes anhydrous magnesium carbonate as Component (b1) and aluminum oxide as Component (b2). Content of the Component (b1) falls within a range from 35% by volume to 65% by volume relative to 100% by volume of the Components (b1) and (b2) combined. Content of the Component (B) falls within a range from 60% by volume to 75% by volume relative to 100% by volume of the resin composition.

An interconnect substrate includes a first insulating layer, an interconnect layer formed on a first surface of the first insulating layer, and a second insulating layer formed on the first surface of the first insulating layer to cover the interconnect layer, wherein the second insulating layer includes a first resin layer and a second resin layer, the first resin layer covering at least part of a surface of the interconnect layer exposed outside the first insulating layer, the second resin layer covering the first resin layer, wherein both the first resin layer and the second resin layer contain a resin and a filler, and wherein a proportion of the resin in the first resin layer per unit area is higher than a proportion of the resin in the second resin layer per unit area.

A printed circuit board according to an embodiment includes a first insulating layer; a first circuit pattern disposed on a lower surface or inside the first insulating layer; a second circuit pattern disposed on an upper surface of the first insulating layer; a second insulating layer disposed on the upper surface of the first insulating layer and surrounding the second circuit pattern; and a protective layer disposed on an upper surface of the second insulating layer, wherein the second insulating layer has at least one recess formed on its upper surface, and wherein the protective layer is disposed in the recess formed on the upper surface of the second insulating layer.