Abstract: An aqueous dispersion of polytetrafluoroethylene (PTFE) comprising from 55 to 70 mass % of PTFE fine particles having an average particle diameter of from 0.1 to 0.5 ?m, from 0.0001 to 0.02 mass %, based on PTFE, of a specific C8 fluorine-containing carboxylic acid salt (APFO) such as ammonium perfluorooctanoate, from 1 to 20 mass %, based on PTFE, of a specific nonionic surfactant and from 0.01 to 0.3 mass %, based on PTFE, of a specific C5-7 fluorine-containing carboxylic acid salt such as ammonium perfluorohexanoate. The aqueous dispersion of PTFE has excellent properties which can form crack-resistant coatings which do not undergo coloration during baking or form problematic ionic impurities by improving the friction stability of aqueous PTFE dispersions even at APFO concentrations without viscosity increase.

Abstract: To obtain a high concentration aqueous PTFE dispersion containing PTFE at a concentration of from 60 to 75 mass % by dissolving from 0.001 to 0.1 mass %, based on the mass of PTFE, of a specific carboxylic acid salt such as ammonium laurate in a low concentration aqueous dispersion of polytetrafluoroethylene (PTFE) comprising from 1 to 40 mass % of PTFE fine particles, from 0.0001 to 0.02 mass %, based on the mass of PTFE, of a specific fluorine-containing carboxylic acid type emulsifier (for example, ammonium perfluorooctanoate), and from 1 to 20 mass %, based on the mass of PTFE, of a specific nonionic surfactant, and then concentrating the low concentration aqueous dispersion of PTFE.

Abstract: Provided are a tetrafluoroethylene copolymer excellent in paste extrudability, which comprises a unit based on tetrafluoroethylene and a unit based on a monomer represented by a formula of CF2?CF—O—(CF2)nCF?CF2 (wherein n is an integer of from 1 to 6), wherein a content of the unit based on the monomer represented by the formula is from 0.1 to 0.5% by mass, wherein a particle size of a primary particle is from 0.1 to 0.5 ?m, wherein a standard specific gravity is from 2.14 to 2.25, wherein a paste extrusion pressure is from 24.5 to 73.5 MPa and wherein the copolymer remains not undergoing melt molding; a fine powder of a tetrafluoroethylene copolymer; and a production method and a paste extruded product thereof. The TFE copolymer is excellent in paste extrudability and the molded product thereof is excellent in heat resistance and transparency.

Abstract: Provided is a tetrafluoroethylene copolymer consisting of a unit based on tetrafluoroethylene and a unit based on a monomer represented by CF2?CFORf1Rf2 (where Rf1 is a polyfluoroalkylene group which may contain an etheric oxygen atom and Rf2 is a polyfluorocycloalkyl group which may contain an etheric oxygen atom), wherein a content of the latter is from 0.005 to 0.5% by mass. The tetrafluoroethylene copolymer is excellent both in paste extrudability and in heat resistance, has characteristics such as excellent transparency of a molded product, and is suitably applicable to paste extrusion and compression molding.

Abstract: Provided is a tetrafluoroethylene copolymer consisting of a unit based on tetrafluoroethylene and a unit based on a monomer represented by CF2?CFORf1Rf2 (where Rf1 is a polyfluoroalkylene group which may contain an etheric oxygen atom and Rf2 is a polyfluorocycloalkyl group which may contain an etheric oxygen atom), wherein a content of the latter is from 0.005 to 0.5% by mass. The tetrafluoroethylene copolymer is excellent both in paste extrudability and in heat resistance, has characteristics such as excellent transparency of a molded product, and is suitably applicable to paste extrusion and compression molding.

Abstract: Provided are a tetrafluoroethylene copolymer excellent in paste extrudability, which comprises a unit based on tetrafluoroethylene and a unit based on a monomer represented by a formula of CF2?CF—O—(CF2)nCF?CF2 (wherein n is an integer of from 1 to 6), wherein a content of the unit based on the monomer represented by the formula is from 0.1 to 0.5% by mass, wherein a particle size of a primary particle is from 0.1 to 0.5 ?m, wherein a standard specific gravity is from 2.14 to 2.25, wherein a paste extrusion pressure is from 24.5 to 73.5 MPa and wherein the copolymer remains not undergoing melt molding; a fine powder of a tetrafluoroethylene copolymer; and a production method and a paste extruded product thereof. The TFE copolymer is excellent in paste extrudability and the molded product thereof is excellent in heat resistance and transparency.

Abstract: A PTFE composition comprising a dispersion-polymerized polytetrafluoroethylene (PTFE) and a filler, wherein the powder irregular shape ratio of the PTFE is at most 50%, and a PTFE granulated product obtained by granulating the PTFE composition. The composition is produced by jetting high pressure water to a mixture comprising the dispersion-polymerized PTFE and the filler. The dispersion-polymerized PTFE composition and granulated product thus obtained are suitable for molding.

Abstract: A PTFE composition comprising a dispersion-polymerized polytetrafluoroethylene (PTFE) and a filler, wherein the powder irregular shape ratio of the PTFE is at most 50%, and a PTFE granulated product obtained by granulating the PTFE composition. The composition is produced by jetting high pressure water to a mixture comprising the dispersion-polymerized PTFE and the filler. The dispersion-polymerized PTFE composition and granulated product thus obtained are suitable for molding.