| 摘要 |
PURPOSE:To easily remove a bubble from a gasket and completely eliminate its defect in molding and performance so as to obtain the gasket having a high sealing effect, by filling a metal mold, having an objective shape, with expansive graphite and then reducing a pressure in the metal mold so as to form the expansive graphite by compression molding. CONSTITUTION:When a gasket material is obtained by compressing expansive graphite to a desired thickness and shape, the expansive-graphite gasket is manufactured by forming it in a metal mold by compression molding reducing a pressure in the metal mold after the male-female metal mold, having an objective shape, is filled with the expansive graphite. Then the gasket uses expansive graphite, obtained by the general method, as the expansive graphite, for instance, using expansive graphite expansion treated after natural graphite or the like is treated by a strong acidifier such as thickened sulfuric acid or its mixed liquid or the like further rinsed by water and dehydrated. While the pressure is reduced by a vacuum device, and this reduction of the pressure removes a bubble dispersedly existing in the expansive graphite. In this way, the expansive graphite gasket of uniform density containing few bubbles is obtained. |
