JPS6422509A - Tire having black internal surface - Google Patents

Abstract

PURPOSE:To obtain a tire having a black internal surface, on which frosting white spots pattern does not substantially exist on the internal surface of the tire, by a method wherein internal surface mold releasing agent, containing black dye, is applied on the inner surface of the tire and the tire is vulcanized and molded. CONSTITUTION:Black dye is dispersed into the mold releasing agent of dimethylpolysiloxane or the like, thereafter, inorganic grains, such as the powder of mica, talc or the like, are blended thereinto and coated on the internal surface of a green tire or the like by spraying or the like. After the coating is dried, a bladder is inserted into the tire to vulcanize and mold it in a mold. In order to improve the dispersing property, an interface activating agent and polyethylene grycohol are blended into the solution of the internal surface mold releasing agent. The black dye is blended into the mold releasing agent, therefore, the mottle of color will never be generated even when there is variability in the distribution of the adhering amount of non-volatile content. According to this method, any defect will never be masked since the condition of the surface of the defect is different from the ambient surface of the defect by the defect whereby the discovery of the defect is facilitated.