Abstract: An object of the present invention is to provide a plain bearing which can be further improved in bearing capability, in particular, anti-seizure property, initial conformability and cavitation resistance. In the present invention, a sliding layer 2 is formed on the surface of a bearing alloy layer 1 formed of a copper-based or aluminum-based alloy, and the sliding layer 2 comprises a resin binder obtained by applying a strong shearing force to a composition comprising a polybenzimidazole resin as main constituent and at least one member selected from the group consisting of a polyamide-imide resin, a polyamide resin and an epoxy resin, to make the composition into a polymer alloy, and 25 to 75 mass % of a solid lubricant. Owing to such a constitution, toughness and strength are imparted to the sliding layer 2 and the anti-seizure property, initial conformability and cavitation resistance can also be improved.

Abstract: A semiconductor device includes: first and second metallic plates, each of which includes a heat radiation surface and an inner surface; a semiconductor element between the metallic plates; a block between the second metallic plate and the semiconductor element; a solder member between the second metallic plate and the block; and a resin mold. The heat radiation surface is exposed from the resin mold. The second metallic plate includes a groove for preventing the solder member from expanding outside of the block. The groove is disposed on the inner surface and disposed on an outer periphery of the block. The second metallic plate further includes an inner surface member on an inner surface of the groove. The inner surface member has a solder wettability, which is larger than a solder wettability of the block.

Abstract: A semiconductor device includes: first and second metallic plates, each of which includes a heat radiation surface and an inner surface; a semiconductor element between the metallic plates; a block between the second metallic plate and the semiconductor element; a solder member between the second metallic plate and the block; and a resin mold. The heat radiation surface is exposed from the resin mold. The second metallic plate includes a groove for preventing the solder member from expanding outside of the block. The groove is disposed on the inner surface and disposed on an outer periphery of the block. The second metallic plate further includes an inner surface member on an inner surface of the groove. The inner surface member has a solder wettability, which is larger than a solder wettability of the block.

Abstract: This invention provides crosslinkable-group-containing polyimides of various known thermoplastic polyimide backbone structures, which are provided with far better heat resistance, chemical resistance and mechanical properties than known polyimides of the structures without impairing excellent moldability or formability, superb sliding property, low water absorption property, outstanding electrical properties, high thermal oxidation stability and high radiation resistance, all of which are inherent to the structures.

Abstract: A thermoplastic polyimide having good thermal stability, comprising a repeating unit represented by the chemical formula (1), a molecular terminal being composed of the chemical formula (2) and/or chemical formula (3), characterized in that: a melt viscosity ratio calculated by the numerical formula (1) and/or the numerical formula (3) is within a numerical range shown in the numerical formula (2) and/or the numerical formula (4) and 1,3-bis(4-aminophenoxy)benzene represented by the chemical formula (3) for production of the above polyimide, characterized in that the content of an azo compound is from 0.0 to 0.2%. The thermoplastic polyimide of the present invention has excellent characteristics {circle around (1)} to {circle around (4)} described below. {circle around (1)} It is superior in thermal stability on melting. That is, the degree of lowering of the fluidity on melting with a lapse of time is small and it is possible to apply to conventional melt molding.