Back to results
US 8,971,553 B2Granted
Electret material and electrostatic-type acoustic transducer
AssigneeNitto Denko Corporation
InventorSeiichi Takaoka
Life of this patent
Estimating the term…
Abstract
An electret material having excellent charge retentivity against heat is provided. The electret material 10 includes an electrode plate 1, a semiconducting layer 2 formed on the electrode plate 1, and an electret layer 3 formed on the semiconducting layer 2. The semiconducting layer 2 includes carbon and a fluororesin. This electret material 10 can be inhibited from decreasing in the surface potential of the electret layer 3 when heated to a high temperature.
Claims16
An electret material comprising:
- an electrode plate;
- a semiconducting layer formed on the electrode plate and comprising carbon and a fluororesin;
- and
- an electret layer formed on the semiconducting layer,
- wherein the semiconducting layer has a surface resistance in the range of 1.0×108 to 1.0×1015Ω/□.
2 more elements
An electret material comprising:
- an electrode plate;
- a semiconductor layer formed on the electrode plate;
- and
- an electret layer formed on the semiconducting layer,
- wherein a material of the semiconducting layer comprises carbon and a fluororesin, and the material is a semiconductor, and
- the fluororesin is selected from the group consisting of polytetrafluoroethylene, tetrafluoroethylene/hexafluoropropylene copolymer, and ethylene/tetrafluoroethylene copolymer.
3 more elements
An electrostatic transducer, comprising:
- an electret material comprising:
- an electrode plate;
- a semiconducting layer formed on the electrode plate and comprising carbon and a fluororesin;
- and
- an electret layer formed on the semiconducting layer,
- wherein the semiconducting layer has a surface resistance in the range of 1.0×108 to 1.0×1015Ω/□, and
- a diaphragm which faces the electret material.
4 more elements
Dependencies are inferred from the claim text.