Abstract: The present invention relates to a composition for cleaning a surface of a substrate, which contains as main components, (a) a halogenated hydrocarbon solvent, (b) a fluorine-containing alcohol and (c) an organic acid.

Abstract: A process for preparing a perfluorinated or polyfluorinated aliphatic carboxylic acids wherein a perfluorinated or polyfluorinated aliphatic halide of the formula: R.sub.f X where R.sub.f is a perfluorinated or polyfluorinated aliphatic group and X is a halogen atom is reacted with carbon dioxide in the presence of metal under the irradiation of ultrasound and the reaction product is hydrolyzed to form a perfluorinated or polyfluorinated aliphatic carboxylic acid of the formula: R.sub.f COOH where R.sub.f is the same as defined above.

Abstract: An alkylated or alkenylated malonic ester having a fluorine containing aliphatic substituent and derivatives thereof as expressed by the following general formula: ##STR1## where R.sub.f is a fluorine containing aliphatic group, R is an aliphatic group, or hydrogen or alkali metal atom, and R' is an unsubstituted or substituted aliphatic group.And a method to trap the enolate ion of a malonic ester having a fluorine containing aliphatic substituent as expressed by the following general formula,R.sub.f CH(CO.sub.2 R).sub.2where R.sub.f is a fluorine containing aliphatic group and R is an aliphatic group, hydrogen or alkali metal atom, wherein said malonic ester is converted under the action of a weaker base and/or fluoride ion to a fluorine containing enolate ion to be trapped as expressed by the following general formula:R.sub.f C.sup..crclbar. (CO.sub.2 R).sub.2where R.sub.f and R are the same as above.

Abstract: A polymeric dielectric material comprising a terpolymer which comprises 30 to 90% by mole of VdF, 5 to 70% by mole of TrFE and 0.1 to 20% by mole of HFP, having large permittivity, which is improved by heat treatment.

Abstract: Novel strains of Rhizobium phaseoli which do not produce acidic extracellular polysaccharides or their constituents, which produces cyclic .beta.-1,2-glucan effectively.

Abstract: A material for optical disks which comprises a polymer containing at least 20 wt. % of a structural unit represented by the formula ##STR1## wherein X is fluorine or alkyl having 1 to 6 carbon atoms, and R.sup.1 is fluoroalkyl having 2 to 10 carbon atoms.

Abstract: A copolymer for optical fibers of fluoroalkylmethacrylate and methacrylic acid, the fluoroalkylmethacrylate having such properties that a homopolymer made of only the fluoroalkylmethacrylate has a glass transition temperature and a refractive index each in the range given by the following formulae (I) and (II), respectively:(1/Tg).ltoreq.9.47.times.10.sup.-3 -4.556.times.10.sup.-3 n.sup.20 (I)n.sup.20 .ltoreq.1.42 (II)wherein Tg represents the glass transition temperature (.degree.K.) of the homopolymer and n.sup.20 represents the refractive index thereof.

Abstract: A process for preparing a polymeric piezoelectric material which comprises a vinylidene fluoride containing polymer, comprising applying at least two cycles of alternate electric field except a rectangular wave to the material to polarize it, by which process, the polymeric piezoelectric material is prepared at a low temperature for a short time.

Abstract: A fluorine-containing olefin of the formula: CF.sub.2 .dbd.CF(CF.sub.2).sub.m (CH.sub.2).sub.n OH wherein m is 0 or an integer of 1 to 10 and n is an integer of 1 to 4, which is copolymerizable with various ethylenically unsaturated compounds and provide fluorine-containing copolymers useful as raw materials for room temperature curing paints, fluorine-containing rubbers and the like.

Abstract: Working fluids for the Rankine cycle comprising chlorodifluoromethane and one of difluoroethane and dichlorotetrafluoroethane.

Abstract: An aqueous fire-extinguishing composition comprising an aqueous solvent and a water-soluble high molecular compound which contains a fluoroalkyl group and a water-solubilizable group, has an average molecular weight of not less than 5,000 and fluorine content of not less than 10% by weight and is soluble in water in an amount of at least 0.1% by weight at 25.degree. C. and the surface tension of which is not more than 50 dyn/cm when measured on 0.1 to 5.0% by weight aqueous solution at 25.degree. C. has excellent fire-extinguishing performance on fire of cooking oil, particularly of frying oil.

Abstract: A copolymer for optical fibers of fluoroalkylmethacrylate and acrylic acid.

Abstract: Working fluids for the Rankine cycle comprising trichlorofluoromethane and a member selected from the group consisting of difluoroethane, isobutane and octafluorocyclobutane.

Abstract: Mixture of tetrafluoroethylene/hexafluoropropylene (TFE/HFP) copolymers comprising 5 to 20% by weight of hexafluoropropylene, the specific melt viscosity at 380.degree. C. of which is from 1.times.10.sup.4 to 60.times.10.sup.4 poise,(a) the melt flow ratio being at least 3.5, and(b) the zero strength time (ZST, second) at 380.degree. C. satisfying the following equation:ZST.gtoreq.1/3x.sup.2 +17x+107wherein x is (specific melt viscosity).times.10.sup.-4 having an improved extrudability, particularly an improved extrusion speed. These mixtures of copolymers contain a high specific melt viscosity portion and a low specific melt viscosity portion.

Abstract: An undercoating composition for a fluorocarbon polymer coating comprising:(a) a modified tetrafluoroethylene polymer in the form of particles of double-layer structure having a core and a shell, the core comprising a tetrafluoroethylene homopolymer or a copolymer of tetrafluoroethylene with a fluorine-containing .alpha.-olefin, the shell comprising a copolymer of tetrafluoroethylene and said fluorine-containing .alpha.-olefin copolymerized therewith in a larger amount than in the core,(b) a copolymer of tetrafluoroethylene and said fluorine-containing .alpha.-olefin, and(c) an auxiliary adhesive agent selected from the group consisting of polyimide, polybismaleimide, polyamideimide and aromatic polyamide.

Abstract: An electrically conductive coating composition which comprises (a) a dispersion of carbon black or a mixture of carbon black and graphite in an organic solvent and (b) a solution of a polymer in an organic solvent, the viscosity of the composition being higher than those of the dispersion (a) and the solution (b) being homogeneous and stable, a coating film formed therefrom having a low volume resistivity.

Abstract: In a heat exchanger for an air conditioning system including a plurality of heat exchanger tubes and a plurality of fins secured to outer surfaces of the heat transfer tubes, the fins are of a special constructional form, such as slitted fins having slits formed in flat or convoluted fins or spine fins, and the heat transfer tubes are each formed on its inner wall surface with spiral grooves or two systems of spiral grooves of large number. The heat transfer tubes define therein a refrigerant passage while the adjacent two fins define therebetween an air passage extending past the outer surfaces of the heat transfer tubes.

Abstract: A fluorine-containing copolymer comprising monomeric units of(a) from 95.8 to 80% by weight of tetrafluoroethylene,(b) from 4 to 14% by weight of hexafluoropropene, and(c) from 0.2 to 6% by weight of perfluorovinyl ether of the formula: ##STR1## wherein n is an integer of 1 to 4, and m is an integer of 0 to 3, and having excellent stress crack resistance when formed into a molded article.

Abstract: A novel fluorine-containing copolymer having functional groups comprising structural units of 1,1-difluoroethylene and structural units of a monomeric compound of the formula: ##STR1## wherein X is --OH, ##STR2## or --COOH group, m is 0 or an integer of 1 to 10 and n is an integer of 1 to 4, which may futher contain structural units of at least one monomer selected from the group consisting of tetrafluoroethylene, chlorotrifluoroethylene, monofluoroethylene 1,1,2-trifluoroethylene, hexafluoropropene and a fluoroalkyl vinyl ether. The copolymer is curable at room temperature, and is useful as a material for fluorine-containing rubbers, molded articles and paints.

Abstract: An optically active substance consisting of perfluoro-2-alkoxy carboxylic acid or its derivative represented by the following general formula: ##STR1## where R.sub.f and R.sub.f ' are the same or different perfluoroaliphatic groups, X is a halogen or hydroxyl group, and C is a chiral carbon atom, the above carboxylic acid or its derivative being useful for an analytical reagent for optically active compounds, such as a chiral derivatizing agent for the .sup.19 F NMR or gas chromatographic analysis.