Abstract: A composition containing polytetrafluoroethylene and substantially free from a compound represented by Formula (3): (H—(CF2)8—SO3)qM2 wherein M2 is H, a metal atom, NR54 (where R5s may be the same as or different from each other and are each H or an organic group having 1 to 10 carbon atoms), an imidazolium optionally having a substituent, a pyridinium optionally having a substituent, or a phosphonium optionally having a substituent, and q is 1 or 2. Also disclosed is a molded boy including the composition.

Abstract: A method for producing polytetrafluoroethylene, which includes polymerizing tetrafluoroethylene in an aqueous medium in the presence of a nucleating agent and a hydrocarbon anionic surfactant to obtain polytetrafluoroethylene. A total amount of the nucleating agent and the hydrocarbon anionic surfactant at the initiation of polymerization is more than 50 ppm based on the aqueous medium.

Abstract: The solid-state imaging element includes a photoelectric converter, a first separator, and a second separator. The photoelectric converter is configured to perform photoelectric conversion of incident light. The first separator configured to separate the photoelectric converter is formed in a first trench formed from a first surface side. The second separator configured to separate the photoelectric converter is formed in a second trench formed from a second surface side facing a first surface. The present technology is applicable to an individual imaging element mounted on, e.g., a camera and configured to acquire an image of an object.

Abstract: There is provided a imaging device including: an N-type region formed for each pixel and configured to perform photoelectric conversion; an inter-pixel light-shielding wall penetrating a semiconductor substrate in a depth direction and formed between N-type regions configured to perform the photoelectric conversion, the N-type regions each being formed for each of pixels adjacent to each other; a P-type layer formed between the N-type region configured to perform the photoelectric conversion and the inter-pixel light-shielding wall; and a P-type region adjacent to the P-type layer and formed between the N-type region and an interface on a side of a light incident surface of the semiconductor substrate.

Abstract: A method for producing a fluoropolymer aqueous dispersion, the method including concentrating a composition comprising a polymer (I) containing a polymerization unit (I) derived from a monomer (I) represented by the general formula (I), a fluoropolymer excluding the polymer (I), a nonionic surfactant, a fluorine-free anionic surfactant, and an aqueous medium to thereby obtain an aqueous dispersion containing the fluoropolymer, CX1X3?CX2R(—CZ1Z2-A0)m??(I) wherein X1 and X3 are each independently F, Cl, H, or CF3; X2 is H, F, an alkyl group, or a fluorine-containing alkyl group; A0 is an anionic group; R is a linking group; Z1 and Z2 are each independently H, F, an alkyl group, or a fluorine-containing alkyl group; and m is an integer of 1 or more.

Abstract: A method for producing an aqueous dispersion of purified polytetrafluoroethylene, the method including: removing or reducing a compound represented by Formula (1) or (2) below from an aqueous dispersion of polytetrafluoroethylene obtained using a hydrocarbon surfactant: (H—(CF2)m—COO)pM1; or??Formula (1): (H—(CF2)n—SO3)qM2.??Formula (2): Also disclosed is a composition containing polytetrafluoroethylene substantially free from a compound represented by Formula (3) below and a molded body including the composition: (H—(CF2)8—SO3)qM2.

Abstract: Powder including low molecular weight polytetrafluoroethylene having a melt viscosity of 1×102 to 7×105 Pa·s at 380° C., having a melt viscosity of 1×102 to 7×105 Pa·s at 380° C., having an average particle size of 1.0 to 50 ?m, and containing 30 or more carboxyl groups at ends of the molecule chain per 106 carbon atoms in the main chain, wherein the powder is substantially free from C8-C14 perfluorocarboxylic acids and salts thereof.

Abstract: A fluoropolymer composition production method for producing a fluoropolymer composition containing a fluoropolymer, the method which includes polymerizing a fluoromonomer in a reactor in the presence of a fluorine-containing surfactant, a polymerization initiator, and an aqueous medium to prepare an aqueous dispersion comprising a fluoropolymer; feeding an inert gas to the reactor; and subjecting to a heat treatment the aqueous dispersion in the reactor to give a fluoropolymer composition, wherein a temperature of the heat treatment is 35° C. or higher and a time of the heat treatment is 15 minutes or more.

Abstract: Provided is a fluoropolymer composition production method for producing a fluoropolymer composition containing a fluoropolymer, the method which includes polymerizing a fluoromonomer in a reactor in the presence of a fluorine-containing surfactant, a polymerization initiator, and an aqueous medium to prepare an aqueous dispersion containing a fluoropolymer; after the aqueous dispersion is prepared, removing from the reactor the fluoromonomer remaining in the reactor, or recovering the aqueous dispersion in the reactor and accommodating the aqueous dispersion in a container different from the reactor; adding a radical generator to the aqueous dispersion; and subjecting to a heat treatment the aqueous dispersion comprising the radical generator to give a fluoropolymer composition.

Abstract: A method for producing a fluoropolymer, which includes polymerizing a fluoromonomer in an aqueous medium in the presence of a polymer (1), the polymer (1) including a polymerized unit derived from a monomer CX2?CY(—CZ2—O—Rf-A), wherein X is the same or different and is —H or —F; Y is —H, —F, an alkyl group, or a fluorine-containing alkyl group; Z is the same or different and is —H, —F, an alkyl group, or a fluoroalkyl group; Rf is a C1-C40 fluorine-containing alkylene group or a C-C100 fluorine-containing alkylene group and having an ether bond; and A is —COOM, —SO3M, or —OSO3M, wherein M is —H, a metal atom, —NR74, imidazolium optionally having a substituent, pyridinium optionally having a substituent, or phosphonium optionally having a substituent, wherein R7 is H or an organic group, providing that at least one of X, Y, and Z contains a fluorine atom.

Abstract: A method for producing a fluoropolymer, which includes polymerizing a fluoromonomer in an aqueous medium in the presence of a polymer (1), the polymer (1) including a polymerized unit derived from a monomer CX2?CY(—CZ2—O—Rf-A), wherein X is the same or different and is —H or —F; Y is —H, —F, an alkyl group, or a fluorine-containing alkyl group; Z is the same or different and is —H, —F, an alkyl group, or a fluoroalkyl group; Rf is a C1-C40 fluorine-containing alkylene group or a C—C100 fluorine-containing alkylene group and having an ether bond; and A is —COOM, —SO3M, or —OSO3M, wherein M is —H, a metal atom, —NR74, imidazolium optionally having a substituent, pyridinium optionally having a substituent, or phosphonium optionally having a substituent, wherein R7 is H or an organic group, providing that at least one of X, Y, and Z contains a fluorine atom.

Abstract: A method for producing a fluoropolymer which includes polymerizing a fluoromonomer in an aqueous medium in the presence of a surfactant to provide a fluoropolymer, the surfactant being represented by the general formula (1): CR1R2R4—CR3R5—X-A, wherein R1 to R5 are each H or a monovalent substituent, with the proviso that at least one of R1 and R3 represents a group represented by the general formula: —Y—R6 and at least one of R2 and R3 represents a group represented by the general formula: —X-A or a group represented by the general formula: —Y—R6; and A is the same or different at each occurrence and is —COOM, —SO3M, or —OSO3M. Also disclosed is a surfactant for polymerization represented by the general formula (1), a method for producing a fluoropolymer using the surfactant, a composition including a fluoropolymer and the surfactant and a molded body including the composition.

Abstract: Powder including low molecular weight polytetrafluoroethylene having a melt viscosity of 1×102 to 7×105 Pa·s at 380° C., having a melt viscosity of 1×102 to 7×105 Pa·s at 380° C., having an average particle size of 1.0 to 50 ?m, and containing 30 or more carboxyl groups at ends of the molecule chain per 106 carbon atoms in the main chain, wherein the powder is substantially free from C8-C14 perfluorocarboxylic acids and salts thereof.

Abstract: A method for producing a fluoropolymer which includes polymerizing a fluoromonomer in an aqueous medium in the presence of a surfactant to provide a fluoropolymer, the surfactant being represented by the general formula (1): CR1R2R4—CR3R5—X-A, wherein R1 to R5 are each H or a monovalent substituent, with the proviso that at least one of R1 and R3 represents a group represented by the general formula: —Y—R6 and at least one of R2 and R5 represents a group represented by the general formula: —X-A or a group represented by the general formula: —Y—R6; and A is the same or different at each occurrence and is —COOM, —SO3M, or —OSO3M. Also disclosed is a surfactant for polymerization represented by the general formula (1), a method for producing a fluoropolymer using the surfactant and a composition including a fluoropolymer and the surfactant.

Abstract: Powder including low molecular weight polytetrafluoroethylene having a melt viscosity of 1×102 to 7×105 Pa·s at 380° C., having a melt viscosity of 1×102 to 7×105 Pa·s at 380° C., having an average particle size of 1.0 to 50 ?m, and containing 30 or more carboxyl groups at ends of the molecule chain per 106 carbon atoms in the main chain, wherein the powder is substantially free from C8-C14 perfluorocarboxylic acids and salts thereof.

Abstract: A method for producing a composition containing low molecular weight polytetrafluoroethylene, the method including: (I) irradiating a composition containing high molecular weight polytetrafluoroethylene with ionizing radiation to obtain a composition containing low molecular weight polytetrafluoroethylene having a melt viscosity at 380° C. in the range of 1.0×102 to 7.0×105 Pa·s; and (II) carrying out at least one selected from the group consisting of washing treatment, steam treatment and decompression treatment on the composition containing low molecular weight polytetrafluoroethylene.

Abstract: A composition including a fluoropolymer and substantially free from a compound represented by the following formula (3): (H—(CF2)8—SO3)qM2, wherein M2 is H, a metal atom, NR54, imidazolium optionally containing a substituent, pyridinium optionally containing a substituent, or phosphonium optionally containing a substituent; R5s are each H or an organic group and are the same as or different from each other; and q is 1 or 2.

Abstract: A method for producing a fluoropolymer of the invention which includes polymerizing a fluoromonomer in an aqueous medium in the presence of a surfactant to provide a fluoropolymer. The surfactant includes at least one selected from the group consisting of a surfactant represented by R1a—CO—R2a—CO—R3a-Aa and a surfactant represented by R1b—CO—(CR2b2)n—(OR3b)p—(CR4b2)q-L-Ab.

Abstract: A water treatment method including a removal step of removing a polymer (I) containing a polymerization unit (I) based on a monomer represented by the following general formula (I) from water containing the polymer (I): CX1X3?CX2R(—CZ1Z2-A0)m??(I) wherein X1 and X3 are each independently F, Cl, H, or CF3; X2 is H, F, an alkyl group, or a fluorine-containing alkyl group; A0 is an anionic group; R is a linking group; Z1 and Z2 are each independently H, F, an alkyl group, or a fluorine-containing alkyl group; and m is an integer of 1 or more. Further, the number average molecular weight of the polymer (I) to 0.3×104 or more. Also disclosed is a composition including the polymer (I) containing the polymerization unit (I) based on a monomer represented by general formula (I), and where the composition has a content of the polymer (I) of 250 ppm or less.

Abstract: A method for producing a fluoropolymer powder including (A1) adding, to a fluoropolymer aqueous dispersion obtained by polymerization using a carboxylic acid type hydrocarbon surfactant, and an acid to adjust a pH to 4.0 or less and cause coagulation to thereby obtain a wet fluoropolymer powder containing a fluorine-containing compound represented by the following general formula (1A), and (B1) heat-treating the wet fluoropolymer powder at a temperature higher than 150° C. and lower than 240° C.: General Formula (1A): H—(CF2)m—COOH wherein m is 3 to 19.