Abstract: The invention provides a film having a high relative permittivity, a high volume resistivity, and a high breakdown strength. The film has a relative permittivity of 9 or higher at a frequency of 1 kHz and 30° C., a volume resistivity of 5E+15 ?·cm or higher at 30° C., and a breakdown strength of 500 V/?m or higher.

Abstract: The invention provides a film having a high relative permittivity, a high volume resistivity, and a high breakdown strength. The film has a relative permittivity of 9 or higher at a frequency of 1 kHz and 30° C., a volume resistivity of 5E+15 ?·cm or higher at 30° C., and a breakdown strength of 500 V/?m or higher.

Abstract: The invention provides a cross-linked fluororesin having excellent abrasion resistance against metal. The cross-linked fluororesin is obtainable by cross-linking a fluororesin. The fluororesin contains a tetrafluoroethylene unit and a vinylidene fluoride unit, and the tetrafluoroethylene unit represents 50.0 mol % or more of all the monomer units constituting the fluororesin.

Abstract: An oral composition comprising trifluoromethionine as an effective component is provided as a useful oral composition for preventing and/or treating intraoral diseases such as bad breath, periodontal disease, alveolar pyorrhea, etc., which is safe even if daily used.

Abstract: A piezoelectric polymeric material having utility in ultrasonic transducers is disclosed which consists essentially of a copolymer of about 65 to 82 mol percent of vinylidene fluoride and about 35 to 18 mol percent of ethylene trifluoride. The polymeric material is formed into a film of the desired thickness and then heated to a temperature greater than about the crystal phase transition temperature and less than about the melting-point temperature to produce a heat-treated film. The heat-treated film is poled in an electrical field of from about 50 to about 1,500 kilovolts per centimeter to give the film a thickness extensional electromechanical coupling factor of at least 0.05 and preferably greater than 0.2.

Abstract: An ultrasonic transducer is disclosed which includes a vibrating element comprising a sheet of a piezoelectric polymeric material which consists essentially of a copolymer of about 65 to 82 mol percent of vinylidene fluoride and about 35 to 18 mol percent of ethylene trifluoride. The polymeric material is formed into a film of the desired thickness and then heated to a temperature greater than about the crystal phase transition temperature and less than about the melting-point temperature for a period of time of about ten minutes to about two hours to produce a heat-treated film. The heat-treated film is poled in an electrical field of from about 50 to about 1,500 kilovolts per centimeter to give the film a thickness extensional electromechanical coupling factor of at least 0.05 and preferably greater than 0.2.