Abstract: A frosting agent in which particulate silica suspends with high dispersibility without lowering the flow-out and formability of an aqueous polyurethane as a binder of frosting coating agent. Such a frosting agent for use in an aqueous polyurethane is obtained by adding 0.5-5.0 parts by weight of .gamma.-ureidopropyltriethoxysilane and 0.1 part by weight or more of water to 100 parts by weight of particulate silica and reacting said substances at a temperature of 15.degree.-100.degree. C. to modify the surface of said particulate silica. By this reaction, .gamma.-ureidopropylsilane liberated by hydrolysis of ethoxysilane groups reacts with acid hydroxy groups. Thus, the wettability and compatibility of the frosting agent with respect to aqueous polyurethane increases. This improves the dispersibility and the resistance to scuff of the coating.

Abstract: A vulcanized rubber article which comprises a vulcanized rubber layer, and non-porous and homogenized thermoplastic polyurethane layer(s) having an average thickness of 0.02-1.0 mm on at least one surface of the vulcanized rubber layer, said polyurethane layer(s) being integrally fused to the vulcanized rubber and the peeling strength between the rubber layer and the polyurethane layer being at least 1.2 kg/cm, and a process for production thereof. The article simplifies the process for production of shoes and makes the control of the process of production readily, and provide a final production having an excellent flexibility, flexing resistance, friction resistance, oil resistance, cleavage resistance against ozone and the like.