Abstract: A semiconductor device (21) can include, e.g., a recessed portion (25) on the reverse surface (224) of an insulating resin (22) which is the mounting surface of the semiconductor device (21). Additionally, on the outer peripheral surface of the recessed portion (25), the exposed region of leads (26) and the reverse surface (224) of the insulating resin (22) form generally the same plane. This allows, e.g., a QFN semiconductor device (21) according to preferred embodiments herein to place dust particles in the recessed portion (25) even in the presence of dust particles such as crushed burr particles of the leads (26) or plastic burrs, thereby avoiding mounting deficiencies when mounting the semiconductor device.
Abstract: A pneumatic tire includes main grooves 1 extending substantially in a circumferential direction R of the tire, transverse grooves 2 connecting adjacent main grooves, and blocks 3 formed by adjacent main grooves and adjacent transverse grooves. Each block 3 has an acute corner portion 3a and an obtuse corner portion 3b and also has a groove side extending along the main groove 1 between the acute corner portion 3a and the obtuse corner portion 3b. An inclination angle a1 of the groove side increases from the obtuse corner portion 3b toward the acute corner portion 3a. An extending direction 1a of the main groove 1 at a tread surface level is inclined toward one side of the main groove 1 with respect to the circumferential direction R of the tire, while an extending direction of the main groove 1 at a groove bottom level is inclined toward the other side.
Abstract: A non-halogen series floor material includes a first intermediate resin layer containing filler of 100 to 400 mass parts with respect to resin ingredient of 100 mass parts, the resin ingredient consisting essentially of resin having no chlorine atom in chemical structure, a surface resin layer integrally formed at an upper surface side of the first intermediate resin layer, the surface resin layer containing resin having no chloride atom in chemical structure and having a thickness of 100 to 1,000 ?m, a second intermediate resin layer integrally formed at a lower surface side of the first intermediate resin layer, the second intermediate resin layer containing resin having no chloride atom in chemical structure and filler of 0 to 200 mass parts with respect to resin ingredient of 100 mass parts, and a backing layer integrally formed at a lower surface side of the second intermediate resin layer, the backing layer being formed of a fibrous fabric constituted by fibers containing resin having no chloride atom i