A fluorinated polymer suitable for deposition and capable of favorable metal patterning, is provided. A resin film containing such a fluorinated polymer as a material is provided. Further, a photoelectronic element having such a resin film in its structure is provided.

A fluorinated polymer which satisfies the following requirements (1) to (3): (1) the melting point is less than 200° C., or no melting point is observed, (2) the thermogravimetric loss rate when the temperature is increased at a temperature-increasing rate of 2° C./min under a pressure of 1×10.sup.−3 Pa, substantially reaches 100% at 400° C. or lower, (3) when the temperature is increased at a temperature-increasing rate of 2° C./min under a pressure of 1×10.sup.−3 Pa, the temperature width from a temperature at which the thermogravimetric loss rate is 10% to a temperature at which it is 90%, is within 200° C.

The invention provides novel compositions comprising semifluorinated alkanes and at least one compound sensitive or prone to oxidation. The compositions can be used as medicines that are topically administered to an eye or ophthalmic tissue. The invention further provides kits comprising such compositions.

The invention provides novel compositions comprising semifluorinated alkanes and at least one compound sensitive or prone to oxidation. The compositions can be used as medicines that are topically administered to an eye or ophthalmic tissue. The invention further provides kits comprising such compositions.

A method for producing low molecular weight polytetrafluoroethylene having a melt viscosity at 380° C. of 1.0×10.sup.2 to 7.0×10.sup.5 Pa.Math.s. The method includes: (1) irradiating high molecular weight polytetrafluoroethylene with radiation in the presence of a substance capable of generating a free hydrogen atom and decomposing the high molecular weight polytetrafluoroethylene into a low molecular weight component; and (2) deactivating at least part of main-chain radicals and end radicals generated by the irradiation and providing the low molecular weight polytetrafluoroethylene. Also disclosed is a composition containing the low molecular weight polytetrafluoroethylene and a low molecular weight polytetrafluoroethylene.

A method for producing low molecular weight polytetrafluoroethylene having a melt viscosity at 380° C. of 1.0×10.sup.2 to 7.0×10.sup.5 Pa.Math.s. The method includes: (1) irradiating high molecular weight polytetrafluoroethylene with radiation in the presence of a substance capable of generating a free hydrogen atom and decomposing the high molecular weight polytetrafluoroethylene into a low molecular weight component; and (2) deactivating at least part of main-chain radicals and end radicals generated by the irradiation and providing the low molecular weight polytetrafluoroethylene. Also disclosed is a composition containing the low molecular weight polytetrafluoroethylene and a low molecular weight polytetrafluoroethylene.

A composition including a fluoropolymer and substantially free from a compound represented by the following formula (3): (H—(CF.sub.2).sub.8—SO.sub.3).sub.qM.sup.2, wherein M.sup.2 is H, a metal atom, NR.sup.5.sub.4, imidazolium optionally containing a substituent, pyridinium optionally containing a substituent, or phosphonium optionally containing a substituent; R.sup.5s are each H or an organic group and are the same as or different from each other; and q is 1 or 2.

A composition including a fluoropolymer and substantially free from a compound represented by the following formula (3): (H—(CF.sub.2).sub.8—SO.sub.3).sub.qM.sup.2, wherein M.sup.2 is H, a metal atom, NR.sup.5.sub.4, imidazolium optionally containing a substituent, pyridinium optionally containing a substituent, or phosphonium optionally containing a substituent; R.sup.5s are each H or an organic group and are the same as or different from each other; and q is 1 or 2.

A composition including a fluoropolymer and substantially free from a compound represented by the following formula (3): (H—(CF.sub.2).sub.8—SO.sub.3).sub.qM.sup.2, wherein M.sup.2 is H, a metal atom, NR.sup.5.sub.4, imidazolium optionally containing a substituent, pyridinium optionally containing a substituent, or phosphonium optionally containing a substituent; R.sup.5s are each H or an organic group and are the same as or different from each other; and q is 1 or 2.

To provide a liquid composition with which a catalyst layer and a polymer electrolyte membrane will hardly be broken at the time of their formation and a method for producing the liquid composition; and a method for producing a membrane/electrode assembly by which a catalyst layer and a polymer electrolyte membrane will hardly be broken at the time of their formation. A liquid composition comprising a polymer having ion exchange groups, water and an organic solvent, wherein the average secondary particle size of the polymer having ion exchange groups is from 100 to 3,000 nm, and the primary particle size parameter represented by the product of the average primary particle size (nm) and the ion exchange capacity (meq/g dry resin) of the polymer having ion exchange groups, is from 12 to 20.

To provide a liquid composition with which a catalyst layer and a polymer electrolyte membrane will hardly be broken at the time of their formation and a method for producing the liquid composition; and a method for producing a membrane/electrode assembly by which a catalyst layer and a polymer electrolyte membrane will hardly be broken at the time of their formation. A liquid composition comprising a polymer having ion exchange groups, water and an organic solvent, wherein the average secondary particle size of the polymer having ion exchange groups is from 100 to 3,000 nm, and the primary particle size parameter represented by the product of the average primary particle size (nm) and the ion exchange capacity (meq/g dry resin) of the polymer having ion exchange groups, is from 12 to 20.