Abstract: A transducer for detecting pressure changes in pipes by detecting deformation of the pipes and for converting the pressure changes in the pipes into electric signals uses a bimorph as a sensor element. This bimorph is pressed to the pipe surface by means of a holder. The transducer is free from complicated adjustment of the pressing force against the sensor element, very simple in structure, easy to adjust when mounting, light in weight so as to hardly influence an injection system, and less susceptible to effects of noise due to vibration.

Abstract: A polymeric composite heating element comprising a composition composed of a vinylidone fluoride-trifluoroethylene copolymer containing 30-85 mole % of vinylidene fluoride and 3-35% by weight based on the weight of the copolymer of electrically conductive carbon mixed in this copolymer.

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: 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: 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: A process for preparation of a polymeric piezo-electric material and material prepared by said process are described, wherein said process comprises polarizing a polymeric piezo-electric material by a polarization treatment which comprisescooling a vinylidene fluoride-trifluoroethylene copolymer from a temperature higher than the phase transition temperature of said copolymer which exists between room temperature and the melting point of said copolymer, and either maintaining the temperature range at which said copolymer possesses a maximum in dielectric constant occurs, or cooling gradually through said temperature range, while applying an electric field at least within said temperature range.

Abstract: A polymeric dielectric having an outstanding dielectric constant, which essentially consists of a copolymer of vinylidene fluoride and triflouroethylene in a molar ratio of from about 95:5 to 10:90, preferably of from about 85:15 to 20:80, more preferably of from about 75:25 to 35:65.

Abstract: A heating tube adapted to electrically heat a fluid carried therethrough includes an inner tubular layer of polytetrafluoroethylene, a second tubular layer surrounding the inner layer and being formed of a homogeneous mixture of polytetrafluoroethylene and electrically conductive carbon, and a third layer surrounding the second layer and being formed of polytetrafluoroethylene. The three layers are coextruded together. The third layer is cut away at at least two circumferential points and the exposed second layer is there provided with a sintered coating for finely divided silver and finely divided polytetrafluoroethylene. The sintered coating is then wrapped with a silicone resin tape containing dispersed silver particles and a metal ring is then fitted over the silicone resin tape thereby forming an electrical terminal for the heating tube.

Abstract: The fibrillated surface layer of an unsintered extruded mass of a polytetrafluoroethylene is broken by mechanical or electrical force to facilitate evaporation of the lubricant whereby a molded article which is free from defects such as cracks and blisters is obtained upon sintering.