Polymer dielectric comprising copolymer of vinylidene fluoride, tetrafluoroethylene and ethylene
AssigneeKureha Kagaku Kogyo Kabushiki Kaisha
InventorsTeruo Sakagami, Noriyuki Arakawa, Haruko Kakutani
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Abstract
A copolymer of 20 to 33 mol. % vinylidene fluoride, 15 to 45 mol. % of ethylene and 30 to 65 mol. % of tetrafluoroethylene gives a dielectric material having a large dielectric constant of 4.0 or above and a small dielectric dissipation factor (tan .delta.) of 0.8% or below, and is suitable for use as a condenser film.
Claims7
A polymer dielectric comprising a copolymer of 20 to 33 mol. % of vinylidene fluoride, 15 to 45 mol. % of ethylene and 30 to 65 mol. % of tetrafluoroethylene, and having a dielectric constant of 4.0 or above and a dielectric dissipation factor of 0.8% or below at 20.degree. C. and 1 KHz, said copolymer having been obtained through suspension polymerization in water, or bulk polymerization, and having a sufficiently large degree of polymerization to provide said dielectric dissipation factor.
A dielectric film laminate comprising a plurality of dielectric films stacked in layers, each dielectric film comprising a copolymer of 20 to 33 mol. % of vinylidene fluoride, 15 to 45 mol. % of ethylene and 30 to 65 mol. % of tetrafluoroethylene, and having a dielectric constant of 4.0 or above and a dielectric dissipation factor of 0.8% or below at 20.degree. C. and 1 KHz, said copolymer having been obtained through suspension polymerization in water, or bulk polymerization, and having a sufficiently large degree of polymerization to provide said dielectric dissipation factor.
Dependencies are inferred from the claim text.