Abstract: A process for preparing a filler-containing PTFE granular powder, which comprises mixing uniformly a PTFE powder having an average particle size of not more than 100 .mu.m and a (semi-)hydrophilic filler which is surface-treated with an organosilane of the formula: ##STR1## in a two-phase liquid medium comprising water and a water-insoluble organic liquid having a surface tension of not more than 35 dynes/cm at 25.degree. C. Accordingly to the process, the separation of filler can be avoided, and a colorless molded article can be provided.

Abstract: A uniform mixture of a polytetrafluoroethylene molding powder and an organic filler, which can provide moldings having improved properties without lowering the appearance and mechanical property, is obtained without sticking the filler to the wall of a mixer by mixing the molding powder and the filler in the presence of a silane coupling agent and a polar solvent, or by previously treating the organic filler with the silane coupling agent and mixing the treated filler with the molding powder.

Abstract: A tetrafluoroethylene base polymer-containing coating composition comprising a dispersion of a tetrafluoroethylene base polymer having a molecular weight of at least 5,000,000 in a liquid medium containing a surfactant, which is particularly useful for coating a fixing heater roller and a cooking utensil.

Abstract: A process for preparing a PTFE granular powder, which comprises agitating a PTFE powder having an average particle size of not more than 200 .mu.m in a two-phase liquid medium comprising water and at least one halogenated hydrocarbon selected from the group consisting of 1,1-dichloro-2,2,2-trifluoroethane, 1,1-dichloro-2,2,3,3,3-pentafluoropropane and 1,3-dichloro-1,1,2,2,3-pentafluoropropane. The PFTE powder may contain a hydrophilic filler surface-treated with an organosilane or a silicone resin. By using the particular halogenated hydrocarbon, the problemed environmental damage can be reduced, and loss of filler can be decreased.

Abstract: A molding process for preparing long and thick, large porous PTFE articles comprising preparation steps of a powder for molding which includes a step of gelation of PTFE powder; a pre-forming step by a ram-extrusion; a baking step of the pre-formed article under a non-constrained circumstance; and if necessary, a cooling step; said powder for molding being containing a binder which has a melting point of lower than that of PTFE and does not decompose at a baking temperature of PTFE.

Abstract: A fluororesin-containing composition comprising a fluororesin, a fibrous material coated by an electrically conductive oxide, an acrylic resin and a liquid medium wherein the weight ratio of the fluororesin to the fibrous material is from 95:5 to 50:50, and the weight ratio of the fluororesin to the acrylic resin is from 100:0 to 85:15. The coating formed from the composition has good heat, chemical and weather resistance and non-tackiness properties.

Abstract: A fluororesin-containing composition comprising a fluororesin, a fibrous material coated by an electrically conductive oxide, an acrylic resin and a liquid medium wherein the weight ratio of the fluororesin to the fibrous material is from 95:5 to 50:50, and the weight ratio of the fluororesin to the acrylic resin is from 100:0 to 85:15. The coating formed form the composition has good heat, chemical and weather resistance and non-tackiness properties.

Abstract: A tetrafluoroethylene base polymer-containing coating composition comprising a dispersion of a tetrafluoroethylene base polymer having a molecular weight of at least 5,000,000 in a liquid medium containing a surfactant, which is particularly useful for coating a fixing heater roller and a cooking utensil.

Abstract: A tetrafluoroethylene polymer tube which is in a porous form composed of continuous pores and has heat-shrinkability in a radial direction or both radial direction and longitudinal direction of the tube, and a process for producing the same comprising applying pressure into inside of a tetrafluoroethylene polymer tube formed by paste extrusion molding a powder of the tetrafluoroethylene polymer and then sintered while heating the same to a temperature of not higher than the melting initiation temperature of the tetrafluoroethylene polymer to expand the tube to a radial direction only or both radial direction and longitudinal direction of the tube, and then cooling the tube in a pressurized state.

Abstract: An aqueous dispersion comprising an aqueous medium and colloidal particles of a fluorine-containing copolymer having an average particle size of about 0.05 to 1.0 um dispersed therein, each colloidal particle being constructed with a core portion made of a polymer comprising about 99 to 100% by weight of units of tetrafluoroethylene and about 0 to 1% by weight of units of at least one other fluoroolefin and a shell portion made of a polymer comprising about 50 to 97% by weight of units of tetrafluoroethylene and about 3 to 50% by weight of units of chlorotrifluoroethylene, the amount of chlorotrifluoroethylene in the core and shell portions being from about 2.5 to 25% by weight based on the entire amount of the core and shell portions.

Abstract: An electrically conductive coating composition which comprises (a) a dispersion of carbon black or a mixture of carbon black and graphite in an organic solvent and (b) a solution of a polymer in an organic solvent, the viscosity of the composition being higher than those of the dispersion (a) and the solution (b) being homogeneous and stable, a coating film formed therefrom having a low volume resistivity.

Abstract: A fluoroelastomer-containing non-tacky electrically conductive coating composition which comprises (a) a fluoroelastomer, (b) a fluororesin, (c) a coupling agent, (d) an electrically conducting material, (e) a liquid vehicle and optionally (f) an inorganic fibrous material, the weight ratio of the fluoroelastomer (a) and the fluororesin (b) being from 95:5 to 35:65, a coating film formed from which has electrical conductivity as well as the properties inherent to the fluoroelastomer.

Abstract: A heating tube adapted to electrically heat a fluid carried therethrough includes an inner tubular layer of polytetrafluoroethylene, a second tubular layer surrounding the inner layer and being formed of a homogeneous mixture of polytetrafluoroethylene and electrically conductive carbon, and a third layer surrounding the second layer and being formed of polytetrafluoroethylene. The three layers are coextruded together. The third layer is cut away at at least two circumferential points and the exposed second layer is there provided with a sintered coating for finely divided silver and finely divided polytetrafluoroethylene. The sintered coating is then wrapped with a silicone resin tape containing dispersed silver particles and a metal ring is then fitted over the silicone resin tape thereby forming an electrical terminal for the heating tube.

Abstract: The fibrillated surface layer of an unsintered extruded mass of a polytetrafluoroethylene is broken by mechanical or electrical force to facilitate evaporation of the lubricant whereby a molded article which is free from defects such as cracks and blisters is obtained upon sintering.