A modified polytetrafluoroethylene aqueous dispersion having low viscosity at high temperature. The modified polytetrafluoroethylene aqueous dispersion contains a modified polytetrafluoroethylene and a nonionic surfactant, has a modified polytetrafluoroethylene solid concentration of 50 to 70% by mass, is substantially free from a fluorine-containing surfactant, and has a viscosity at 55° C. of 80 mPa•s or lower, and the modified polytetrafluoroethylene contains 0.050% by mass or more and 1.00% by mass or less of a polymerized unit based on a modifying monomer.

A modified polytetrafluoroethylene aqueous dispersion having low viscosity at high temperature. The modified polytetrafluoroethylene aqueous dispersion contains a modified polytetrafluoroethylene and a nonionic surfactant, has a modified polytetrafluoroethylene solid concentration of 50 to 70% by mass, is substantially free from a fluorine-containing surfactant, and has a viscosity at 55° C. of 80 mPa•s or lower, and the modified polytetrafluoroethylene contains 0.050% by mass or more and 1.00% by mass or less of a polymerized unit based on a modifying monomer.

A fluororesin having a tensile strength retention ratio of 50% or more, the tensile strength retention ratio being calculated by the following formula from the tensile strength of the fluororesin after a heat treatment obtained by conducting a heat treatment at 130° C. for 40,000 hours, and the tensile strength of the fluororesin before the heat treatment. Tensile strength retention ratio (%)=(tensile strength of fluororesin after heat treatment (MPa))/(tensile strength of fluororesin before heat treatment (MPa))×100.

A fluororesin having a tensile strength retention ratio of 50% or more, the tensile strength retention ratio being calculated by the following formula from the tensile strength of the fluororesin after a heat treatment obtained by conducting a heat treatment at 130° C. for 40,000 hours, and the tensile strength of the fluororesin before the heat treatment. Tensile strength retention ratio (%)=(tensile strength of fluororesin after heat treatment (MPa))/(tensile strength of fluororesin before heat treatment (MPa))×100.

The present invention relates to a technology of solving an issue where screens are contaminated with pollution caused by fingerprints, cosmetics, etc. on covers or windows of mobile devices such as smartphones, tablets, etc. and other user contact devices, thereby maintaining the excellent surface hardness properties of existing covers or windows and preventing deterioration of surface properties (antifouling properties) even when used long-term. The method for forming a surface having super water-repellent and super oil-repellent properties comprises the steps of: etching a surface of a target on which a surface with super water-repellent and super oil-repellent properties will be formed, to thereby form a surface structure in which convex parts () and concave parts () are continuously formed; and performing a conformal coating for coating a fluorine-based material on the surface structure which is etched on the surface of the target, wherein all configuration walls of the convex parts and all configuration walls of the concave parts are coated at a uniform thickness.

A film containing a resin composition containing an aromatic polyetherketone resin (I) and a fluorine-containing copolymer (II). The fluorine-containing copolymer (II) defines a dispersed phase at an average dispersed particle size of 5 .Math.m or smaller. The aromatic polyetherketone resin (I) has a crystallinity of lower than 6%.

A film containing a resin composition containing an aromatic polyetherketone resin (I) and a fluorine-containing copolymer (II). The fluorine-containing copolymer (II) defines a dispersed phase at an average dispersed particle size of 5 .Math.m or smaller. The aromatic polyetherketone resin (I) has a crystallinity of lower than 6%.

The copolymer includes divalent units represented by formula —[CF.sub.2—CF.sub.2]—, divalent units represented by formula; and one or more divalent units independently represented by formula: The copolymer has an —SO.sub.2X equivalent weight in a range from 300 to 2000. A polymer electrolyte membrane that includes the copolymer and a membrane electrode assembly that includes such a polymer electrolyte membrane are also provided.

The copolymer includes divalent units represented by formula —[CF.sub.2—CF.sub.2]—, divalent units represented by formula; and one or more divalent units independently represented by formula: The copolymer has an —SO.sub.2X equivalent weight in a range from 300 to 2000. A polymer electrolyte membrane that includes the copolymer and a membrane electrode assembly that includes such a polymer electrolyte membrane are also provided.

The present invention relates to: a method of producing a structure having a recessed pattern; a resin composition; a method of forming an electroconductive film; an electronic circuit; and an electronic device. The method of producing a structure having a recessed pattern includes the following steps (i) and (ii), and the recessed pattern has a film thickness that is thinner by 5% to less than 90% with respect to that of a coating film obtained in the step (i): (i) the step of forming a coating film on a non-flat surface of a structure using a resin composition which includes an acid-dissociable group-containing polymer and an acid generator; and (ii) the step of forming a recess by subjecting a prescribed part of a portion of the coating film to irradiation with radiation.