Abstract: A PTC thermistor 10 comprises, at least, a pair of electrodes 2, 3 and a thermistor body 1, disposed between the electrodes 2, 3, having a positive resistance vs. temperature characteristic. The thermistor body includes, at least, a thermoplastic resin and an electrically conductive particle made of a metal powder. The thermoplastic resin and electrically conductive particle have respective contents and a state of dispersion adjusted so as to yield a magnetization of 4.0×10?5 to 6.0×10?5 Wb·m·kg?1 when a magnetic field of 3.98×105 A·m?1 is applied to the thermistor body.

Abstract: A magnetophoretic display panel capable of displaying clear and distinct indicia and erasing the indicia neatly. The display panel includes a multi-cell structure having a thickness of 0.8 to 1.5 mm and formed with a number of cells which contain therein colored liquids and colored magnetic particles. A magnetic pen exhibits an effective magnetic flux density of 100 to 500 Gauss at a bottom of a magnetic panel when positioned on a surface of the magnetic panel. An erasure magnet exhibits an effective magnetic flux density of 300 to 1500 Gauss at the surface of the magnetic panel when positioned on the bottom of the magnetic panel.

Abstract: A magnetophoresis type display device is provided with a transparent front panel sheet, a back panel sheet arranged with respect to the front panel sheet so as to form a sealed space with it, and a partitioning member is between the front panel sheet and the back panel sheet for partitioning the sealed space into a large number of cells, where a liquid dispersion containing magnetic particles is sealed inside the cells formed by partitioning by the partitioning member.

Abstract: A PTC thermistor 10 comprises, at least, a pair of electrodes 2, 3 and a thermistor body 1, disposed between the electrodes 2, 3, having a positive resistance vs. temperature characteristic. The thermistor body includes, at least, a thermoplastic resin and an electrically conductive particle made of a metal powder. The thermoplastic resin and electrically conductive particle have respective contents and a state of dispersion adjusted so as to yield a magnetization of 4.0×10−5 to 6.0×10−5 Wb·m·kg−1 when a magnetic field of 3.98×105 A·m−1 is applied to the thermistor body.

Abstract: A magnetophoresis type display device provided with a transparent front panel sheet, a back panel sheet arranged with respect to the front panel sheet so as to form a sealed space with it, a partitioning member provided between the front panel sheet and the back panel sheet for partitioning the sealed space into a large number of cells, a liquid dispersion containing magnetic particles to be sealed inside the cells formed by partitioning by the partitioning member, a recording magnetic member provided to be able to move along the outer surface of the front panel sheet and having a magnetic force of an extent giving an effective magnetic flux density of 100 to 500 Gauss at the outer surface of the back panel sheet in the state when the recording magnetic member is brought into contact with the outer surface of the front panel sheet, and an erasing magnetic member arranged at the outer surface of the back panel sheet and having a magnetic force of an extent giving an effective magnetic flux density of 100 to 15

Abstract: A magnetophoresis type display device, according to one embodiment, is provided with a transparent front panel sheet, a back panel sheet arranged with respect to the front panel sheet so as to form a sealed space with it, a partitioning member provided between the front panel sheet and the back panel sheet for partitioning the sealed space into a large number of cells and a liquid dispersion containing magnetic particles and a single-color fluid to be sealed inside the cells formed by partitioning by the partitioning member. The single-color fluid is a white fluid that includes at least titanium oxide and silicon oxide in which when the total weight of the white fluid is 100 wt %, the wt % of the titanium oxide in the white fluid is C, and the wt % of the silicon oxide is D, the weight ratio C/D is in the relationship of 1≦C/D≦2.5.

Abstract: Ferrite materials including spinel and magnetoplumbite ferrite materials are prepared by using a mixture containing at least one metal chloride and at least one metal oxide as a starting raw material and roasting the mixture in a steam-containing atmosphere to carry out pyrolysis reaction and solid phase reaction at the same time.

Abstract: Ferrous chloride is used as a starting material and roasted in a steam-containing atmosphere for pyrolysis to prepare a magnetite magnetic powder having a saturation magnetization .sigma.s of 82-92 emu/g and a magnetite phase content of at least 90 wt. %. Prior to roasting, the ferrous chloride may be pre-treated by heat treating it at a low temperature in a non-oxidizing atmosphere, cooling it down to a predetermined temperature, and then exposing it to an oxygen-containing atmosphere. A mixture of ferrous chloride and ferric chloride may also be used as the starting material. These methods can produce magnetite magnetic powder having improved magnetic properties through fewer steps in a simple and easy manner.