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.

Abstract: Provided is a process by which an electret material having excellent thermal resistance of charge retentivity can be obtained. The process for producing an electret material of the invention includes an irradiation step, a formation step, and a charging step. In the irradiation step, a dispersion containing fine polytetrafluoroethylene particles is irradiated with ? rays. In the formation step, the dispersion which has been irradiated with ? rays is applied to an electrode plate and then dried, and the fine polytetrafluoroethylene particles are sintered to form a polytetrafluoroethylene layer on the electrode plate. In the charging step, the surface of the polytetrafluoroethylene layer is subjected to a charging treatment.

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.

Abstract: Provided is a process by which an electret material having excellent thermal resistance of charge retentivity can be obtained. The process for producing an electret material of the invention includes an irradiation step, a formation step, and a charging step. In the irradiation step, a dispersion containing fine polytetrafluoroethylene particles is irradiated with ? rays. In the formation step, the dispersion which has been irradiated with ? rays is applied to an electrode plate and then dried, and the fine polytetrafluoroethylene particles are sintered to form a polytetrafluoroethylene layer on the electrode plate. In the charging step, the surface of the polytetrafluoroethylene layer is subjected to a charging treatment.

Abstract: Described are a gas adsorbent which comprises anatase titanium oxide as an adsorbent, preferably, the gas adsorbent obtained by sintering anatase titanium oxide together with fluoro-carbon resin particles, and having an adsorption layer containing 20 wt. % or greater of anatase titanium oxide; and a using method of the gas adsorbent. The gas adsorbent according to the invention has adsorption performance of an odorous substance, can be regenerated in a simple manner and permits decomposition of the adsorbed ingredient upon regeneration.

Abstract: A cathode-ray tube includes an envelope in which a panel portion, a funnel portion, and a neck portion are integrally formed, and a conductor film and a deflecting yoke mounted on an outer surface of the funnel portion. A strip-type electric field reducing piece has a coated portion coated with an insulator, and an exposed conductive material portion. The coated portion is disposed between the funnel portion and the deflecting yoke, and the conductive material portion is connected to the conductor film.