The present invention is a low dielectric resin substrate, which is a composite including an annealed quartz glass cloth and an organic resin, where the annealed quartz glass cloth has a dielectric loss tangent of less than 0.0010 at 10 GHz, and tensile strength of 1.0 N/25 mm or more per cloth weight (g/m.sup.2). This provides a resin substrate that includes a quartz glass cloth which has a low dielectric loss tangent and which is also excellent in tensile strength.

Described herein is method of making branched perfluorinated compounds, specifically (CF.sub.3).sub.2CFCF(CF.sub.3)OCF(CF.sub.3)C(═O)F and (CF.sub.3).sub.2CFCF(CF.sub.3)OCF═CF.sub.2. Also disclosed herein is a fluoropolymer derived from the branched perfluorovinyl ether monomer and methods of making the fluoropolymer.

Described herein is method of making branched perfluorinated compounds, specifically (CF.sub.3).sub.2CFCF(CF.sub.3)OCF(CF.sub.3)C(═O)F and (CF.sub.3).sub.2CFCF(CF.sub.3)OCF═CF.sub.2. Also disclosed herein is a fluoropolymer derived from the branched perfluorovinyl ether monomer and methods of making the fluoropolymer.

To provide a liquid composition whereby a resin powder can be uniformly dispersed in a resin or the like without being scattered, and a method for producing a film, a laminate or the like by using the liquid composition. The liquid composition comprises a liquid medium and a resin powder dispersed in the liquid medium, and characterized in that the average particle size of the resin powder is from 0.3 to 6 μm, the volume-based cumulative 90% diameter of the resin powder is at most 8 μm, and the resin powder is a resin containing a fluorinated copolymer having a specific functional group. And, the method is a method for producing a film, a laminate or the like by using the liquid composition.

To provide a liquid composition whereby a resin powder can be uniformly dispersed in a resin or the like without being scattered, and a method for producing a film, a laminate or the like by using the liquid composition. The liquid composition comprises a liquid medium and a resin powder dispersed in the liquid medium, and characterized in that the average particle size of the resin powder is from 0.3 to 6 μm, the volume-based cumulative 90% diameter of the resin powder is at most 8 μm, and the resin powder is a resin containing a fluorinated copolymer having a specific functional group. And, the method is a method for producing a film, a laminate or the like by using the liquid composition.

A method for producing a fluoropolymer, which includes polymerizing a monomer (I) represented by the general formula (I) in an aqueous medium to produce the fluoropolymer of the monomer (I), wherein an oxygen concentration in a reaction system of the polymerization is maintained at 500 ppm by volume or less:

CX.sub.2═CY—CF.sub.2—O—Rf-A   General formula (I):

wherein X and Y are independently H, F, CH.sub.3, or CF.sub.3, and at least one of X and Y is F; Rf is a fluorine-containing alkylene group having 1 to 40 carbon atoms, or a fluorine-containing alkylene group having 2 to 100 carbon atoms and having an ether bond; and A is —COOM, —SO.sub.3M, —OSO.sub.3M, or —C(CF.sub.3).sub.2OM, wherein M is H, a metal atom, NR.sup.7.sub.4, imidazolium optionally having a substituent, pyridinium optionally having a substituent, or phosphonium optionally having a substituent, and R.sup.7 is H or an organic group.

Provided is a fluoropolymer of a monomer (I) represented by the following general formula (I), wherein a content of a polymerization unit (I) derived from the monomer (I) is 40 mol % or more based on the entirety of polymerization units constituting the fluoropolymer, and the fluoropolymer has a weight average molecular weight (Mw) of 1.4×10.sup.4 or more:

CX.sub.2═CX—O—Rf-A  General formula (I)

wherein X is independently F or CF.sub.3; Rf is a fluorine-containing alkylene group having 1 to 40 carbon atoms or a fluorine-containing alkylene group having 2 to 100 carbon atoms and having an ether bond or a keto group; and A is —COOM, —SO.sub.3M, —OSO.sub.3M, or —C(CF.sub.3).sub.2OM, wherein M is —H, a metal atom, —NR.sup.7.sub.4, imidazolium optionally having a substituent, pyridinium optionally having a substituent, or phosphonium optionally having a substituent, and R.sup.7 is H or an organic group.

Provided is a fluoropolymer of a monomer (I) represented by the following general formula (I), wherein a content of a polymerization unit (I) derived from the monomer (I) is 40 mol % or more based on the entirety of polymerization units constituting the fluoropolymer, and the fluoropolymer has a weight average molecular weight (Mw) of 1.4×10.sup.4 or more:

CX.sub.2═CX—O—Rf-A  General formula (I)

wherein X is independently F or CF.sub.3; Rf is a fluorine-containing alkylene group having 1 to 40 carbon atoms or a fluorine-containing alkylene group having 2 to 100 carbon atoms and having an ether bond or a keto group; and A is —COOM, —SO.sub.3M, —OSO.sub.3M, or —C(CF.sub.3).sub.2OM, wherein M is —H, a metal atom, —NR.sup.7.sub.4, imidazolium optionally having a substituent, pyridinium optionally having a substituent, or phosphonium optionally having a substituent, and R.sup.7 is H or an organic group.

The present invention is a low dielectric resin substrate, which is a composite including an annealed quartz glass cloth and an organic resin, where the annealed quartz glass cloth has a dielectric loss tangent of less than 0.0010 at 10 GHz, and tensile strength of 1.0 N/25 mm or more per cloth weight (g/m.sup.2). This provides a resin substrate that includes a quartz glass cloth which has a low dielectric loss tangent and which is also excellent in tensile strength.

The present invention is a low dielectric resin substrate, which is a composite including an annealed quartz glass cloth and an organic resin, where the annealed quartz glass cloth has a dielectric loss tangent of less than 0.0010 at 10 GHz, and tensile strength of 1.0 N/25 mm or more per cloth weight (g/m.sup.2). This provides a resin substrate that includes a quartz glass cloth which has a low dielectric loss tangent and which is also excellent in tensile strength.