Abstract: A method for shaping a tetrafluoroethylene resin pipe which comprises:(a) winding a porous sheet of tetrafluoroethylene resin which is not sintered around a mandrel,(b) covering the wound sheet with an elastomeric material,(c) isotactically pressing the wound sheet covered with the elastomeric material,(d) removing the elastomeric material from the wound sheet, and(e) sintering the wound sheet. According to the present invention, a dense tetrafluoroethylene resin pipe having excellent appearance and surface smoothness can be easily obtained, while maintaining the advantages inherent in the conventional winding methods.

Abstract: Use of a composition comprising a polytetrafluoroethylene resin and a fine inorganic powder for a gasket, said composition being characterized in that the polytetrafluoroethylene resin is at least 5% by weight and the fine inorganic powder is at least 40% by weight, based on the total amount of the polytetrafluoroethylene resin and the fine inorganic powder; the total amount of the polytetrafluoroethylene resin and the fine inorganic powder is at least 80% by weight based on the entire amount of the composition; and the polytetrafluoroethylene resin and the fine inorganic powder are mutually uniformly dispersed and mixed with each other.

Abstract: Use of a composition comprising a polytetrafluoroethylene resin and a fine inorganic powder for a gasket, said composition being characterized in that the polytetrafluoroethylene resin is at least 5% by weight and the fine inorganic powder is at least 40% by weight, based on the total amount of the polytetrafluoroethylene resin and the fine inorganic powder; the total amount of the polytetrafluoroethylene resin and the fine inorganic powder is at least 80% by weight based on the entire amount of the composition; and the polytetrafluoroethylene resin and the fine inorganic powder are mutually uniformly dispersed and mixed with each other.

Abstract: Disclosed is a highly heat-resistant disc roll comprising laminated discs, each disc comprising 20 to 90% by weight, based on the total solids of mica particles, 1 to 35% by weight, based on the total solids, of a binder, 5 to 40% weight, based on the total solids, of an inorganic filler and 1 to 30% by weight, based on the total solids, of a reinforcing fiber.

Abstract: This invention relates to a disk roll characterized in that the flaky vermiculite particles obtained by pulverizing the expanded vermiculite, which may be optionally mixed with a fiber material, are dispersed in water and filtered to form a thin sheet as a starting material for disk roll.

Abstract: The asbestos-free calcium silicate heat-resistant material composition, comprises:(A) 100 parts by weight of a mixture of lime and siliceous material having a CaO/SiO.sub.2 mole ratio of 0.6-1.2;(B) 20-170 parts by weight of xonotlite obtained by hydrothermal synthesis;(C) 15-150 parts by weight of fibrous wollastonite; and(D) water in an amount of 2-8 times as much as that of the total solid contents and is produced by a method which comprises the steps of:(i) molding a slurry of a uniform mixture of that recited above in (A) to (D).(ii) steam curing said molded body in an atmosphere of steam under a pressure of not less than 6 kg/cm.sup.2 to react the siliceous material with the lime; and(iii) heat treating said steam cured product to remove water therefrom at a temperature of not lower then 100.degree. C. under atmospheric pressure.

Abstract: This invention relates to a method for making an asbestos-free calcium silicate board, which comprises preparing a slurry of a mixture of silicic acid material, lime material, fibrous wollastonite and pulp with a large amount of water, forming the slurry into a raw board by means of the sheet-forming technique, steaming the raw board and drying. This invention also relates to the board produced in accordance with the above method.