Abstract: The present invention provides an optically clear adhesive sheet using a heat-curable polyurethane composition, wherein the optically clear adhesive sheet can, when bonded to an adherend such as a glass plate, prevent the occurrence of air bubbles even at high temperature and normal humidity and maintain a stable bonded interface. The optically clear adhesive sheet of the present invention is an optically clear adhesive sheet containing: a cured product of a heat-curable polyurethane composition, the heat-curable polyurethane composition containing a polyol component and a polyisocyanate component, the polyol component having an olefin skeleton, the polyisocyanate component containing an acyclic aliphatic polyisocyanate and/or an alicyclic polyisocyanate.

Abstract: The present invention provides an optically clear adhesive sheet with reduced delay bubble generation using a thermosetting polyurethane composition that has excellent flexibility and is capable of giving a thick film. The optically clear adhesive sheet of the present invention is an optically clear adhesive sheet formed of a cured product of a thermosetting polyurethane composition, the optically clear adhesive sheet having a shear storage modulus (G?) at 85° C. of 4.5×103 to 5.0×104 Pa, a loss tangent (tan ?) at 85° C. of 0.3 to 0.97, and a thickness of 50 to 2000 ?m. The optically clear adhesive sheet preferably has an adhesive strength measured by a 180° peel test of 2 N/25 mm or more.

Abstract: An object of the present invention is to provide a grinding material in which grinding portions can be increased in thickness while a decrease in grinding rate is inhibited. The grinding material according to the present invention includes a base, and a grinding layer overlaid on a front face side of the base and containing abrasive grains and a binder. The grinding layer includes a plurality of columnar grinding portions. The plurality of the grinding portions are configured so that the grinding portions are arranged in a staggered manner. The average thickness of the grinding portions is no less than 300 ?m. The area of a top face of each of the grinding portions is no less than 6 mm2. The average thickness of the base is no less than 300 ?m and no greater than 3,000 ?m.

Abstract: The present invention provides an optically clear adhesive sheet with excellent transparency using a thermosetting polyurethane composition that has excellent flexibility and is capable of giving a thick film. The optically clear adhesive sheet of the present invention contains: a cured product of a thermosetting polyurethane composition, the thermosetting polyurethane composition containing a polyol component, a polyisocyanate component, and a tackifier, the thermosetting polyurethane composition having a tackifier content of 5 to 21 wt %.

Abstract: The present invention provides an optically clear adhesive sheet with excellent environment resistance using a thermosetting polyurethane composition that has excellent flexibility and is capable of giving a thick film. The optically clear adhesive sheet of the present invention contains: a cured product of a thermosetting polyurethane composition, the thermosetting polyurethane composition containing an olefin-based polyol component and a polyisocyanate component, the optically clear adhesive sheet exhibiting a moisture absorption of 1.0 wt % or lower after being subjected to a test in a high-temperature, high-humidity environment for eight hours and exhibiting a haze of 1.5% or lower after being subjected to the test in a high-temperature, high-humidity environment for 100 hours, wherein the test in a high-temperature, high-humidity environment is performed at a temperature of 85° C. and a humidity of 85%.

Abstract: The present invention provides an optically clear adhesive sheet with reduced delay bubble generation using a thermosetting polyurethane composition that has excellent flexibility and is capable of giving a thick film. The optically clear adhesive sheet of the present invention is an optically clear adhesive sheet formed of a cured product of a thermosetting polyurethane composition, the optically clear adhesive sheet having a shear storage modulus (G?) at 85° C. of 4.5×103 to 5.0×104 Pa, a loss tangent (tan ?) at 85° C. of 0.3 to 0.97, and a thickness of 50 to 2000 ?m. The optically clear adhesive sheet preferably has an adhesive strength measured by a 180° peel test of 2 N/25 mm or more.

Abstract: The present invention provides an optically clear adhesive sheet using a heat-curable polyurethane composition, wherein the optically clear adhesive sheet can, when bonded to an adherend such as a glass plate, prevent the occurrence of air bubbles even at high temperature and normal humidity and maintain a stable bonded interface. The optically clear adhesive sheet of the present invention is an optically clear adhesive sheet containing: a cured product of a heat-curable polyurethane composition, the heat-curable polyurethane composition containing a polyol component and a polyisocyanate component, the polyol component having an olefin skeleton, the polyisocyanate component containing an acyclic aliphatic polyisocyanate and/or an alicyclic polyisocyanate.

Abstract: A method of manufacturing a power transmission belt includes: molding and vulcanizing an endless tension member layer in which a cord extending in a belt length direction is embedded; molding and vulcanizing a rubber member for a compressed rubber layer; and bonding together the tension member layer that has been vulcanized and the rubber member, that has been vulcanized, for the compressed rubber layer.

Abstract: A method of manufacturing a power transmission belt includes: molding and vulcanizing an endless tension member layer in which a cord extending in a belt length direction is embedded; molding and vulcanizing a rubber member for a compressed rubber layer; and bonding together the tension member layer that has been vulcanized and the rubber member, that has been vulcanized, for the compressed rubber layer.