| 摘要 |
PURPOSE:To obtain a gasket which can be well adapted to a contact surface even when clamping pressure is insufficient and has excellent sealing properties, by blending a water-swelling acrylic fiber with a gasket material mainly composed of a fibrous material, a filler and a rubber material, forming the blend into a sheet and bringing the sheet into contact with ammonia. CONSTITUTION:A water-swelling acrylic fiber in an unswelled state where the carboxyl group is in the form of free -COOH, is blended with a gasket material mainly composed of a fibrous material, a filler and a rubber material. The blend is formed into a sheet in a wet process. The sheet is dried and brought into contact with ammonia to convert the carboxyl group into -COONH4, whereby the sheet is made water-swellable. The water-swelling fiber can be obtd. by introducing a carboxyl group of the formula -COOH or -COOX (wherein X is an alkali metal, NH4) in a quantity of 0.1-40mmol/g into a fiber composed of an acrylonitrile polymer. |
