Abstract: A radio wave absorber provided with a radio wave absorbing film formed on a substrate, the radio wave absorber being capable of absorbing radio waves over a broad frequency band and exhibiting superior radio wave absorbing properties even with a radio wave absorbing film thinner than 1 mm. A film forming paste suitable for forming a radio wave absorbing film that is provided in the radio wave absorber. In a radio wave absorber provided with a radio wave absorbing film formed on a substrate, a particular epsilon-type iron oxide is employed in the radio wave absorbing film and relative permittivity of the radio wave absorbing film is set to 6.5 to 65.

Abstract: There is provided an iron oxide magnetic nanoparticle powder having a ferromagnetic property even if the particles have an average particle size of 15 nm or less, preferably 10 nm or less, and a method of producing the same, an iron oxide magnetic nanoparticle thin film containing the iron oxide magnetic nanoparticle powder and a method of producing the same, wherein the iron oxide magnetic nanoparticles having an ?-Fe2O3 single phase, having the average particle size of 15 nm or less, and further 10 nm or less, are generated by using ?-FeO(OH) (iron oxide hydroxide) nanoparticles as a starting material, and coating the (iron oxide hydroxide) nanoparticles with silicon oxide, and applying heat treatment thereto under an atmospheric air, and further the iron oxide magnetic nanoparticle thin film is obtained by using the iron oxide magnetic nanoparticles.

Abstract: A titanium oxide particle that can develop non-conventional and novel physical properties, a method for manufacturing the same, and a magnetic memory, an optical information recording medium, and a charge accumulation type memory using the same are provided. A silica-coated titanium hydroxide compound particle is directly produced through a sol-gel technique and not through a reverse micelle technique, and the silica-coated titanium hydroxide compound particle is subjected to a calcination process. Hence, a titanium oxide particle 1 can be provided which can develop non-conventional and novel physical properties such that it does not perform phase transition at a room temperature and a Ti3O5 particle body can always maintain the characteristic as a paramagnetic metal in all temperature ranges unlike conventional bulk bodies that perform phase transition between a non-magnetic semiconductor and a paramagnetic metal at a temperature near about 460 K.

Abstract: A microstructure that can develop non-conventional and novel physical properties and a method for producing the same are provided. Ethanol is added to a mixture solution produced by adding a surfactant solution to a peroxotitanic acid aqueous solution to produce precipitates, and the precipitates collected from the mixture solution are let dried to produce precursor powders 5. The precursor powders 5 are calcined at a predetermined temperature. Accordingly, a microstructure 2 can be produced which is formed of monophasic Ti4O7 in nano size. The microstructure 2 of monophasic Ti4O7 produced in this fashion can be fine-grained in nano size unlike prior-art crystals.

Abstract: There are provided titanium oxide particles capable of manifesting an unprecedented property, a manufacturing method thereof and a magnetic memory as well as a charge storage type memory employing the titanium oxide particles. Unlike-conventional bulk bodies phase-transited between nonmagnetic semiconductors and paramagnetic metals around about 460K, provided are titanium oxide particles 3 capable of manifesting an unprecedented property that Ti3O5 particles do not undergo phase transitions at room temperature and allow a paramagnetic metal property thereof to be consistently maintained in any temperature range.

Abstract: There are provided a fine structural body capable of manifesting an unprecedented property; a manufacturing method thereof; and a magnetic memory, a charge storage memory and an optical information recording medium employing such fine structural body. Unlike conventional bulk bodies phase-transited between nonmagnetic semiconductors and paramagnetic metals around about 460K, there can be provided a fine structural body 1 comprised of Ti3O5, but capable of manifesting an unprecedented property in which a paramagnetic metal property thereof is consistently maintained in all temperature ranges without undergoing phase transition to a nonmagnetic semiconductor.

Abstract: Disclosed is a magnetic material having high Hc and High Curie point, which is capable of controlling such magnetic characteristics without requiring rare or expensive raw materials. Specifically disclosed is a magnetic material composed of particles of a magnetic iron oxide which is represented by the following general formula: ?-AxByFe2?x?yO3 or ?-AxByCzFe2?x?y?zO3 (wherein A, B and C each represents a metal excluding Fe and different from each other, satisfying 0<x, y, z<1), with ?-Fe2O3 as a main phase.

Abstract: A titanium oxide particle that can develop non-conventional and novel physical properties, a method for manufacturing the same, and a magnetic memory, an optical information recording medium, and a charge accumulation type memory using the same are provided. A silica-coated titanium hydroxide compound particle is directly produced through a sol-gel technique and not through a reverse micelle technique, and the silica-coated titanium hydroxide compound particle is subjected to a calcination process. Hence, a titanium oxide particle 1 can be provided which can develop non-conventional and novel physical properties such that it does not perform phase transition at a room temperature and a Ti3O5 particle body can always maintain the characteristic as a paramagnetic metal in all temperature ranges unlike conventional bulk bodies that perform phase transition between a non-magnetic semiconductor and a paramagnetic metal at a temperature near about 460 K.

Abstract: [Problem] When a nonreciprocal device operating at 100 GHz to 300 GHz is to be realized by using a conventional magnetic material of garnet-type ferrite or spinel-type ferrite, a huge permanent magnet is required and, therefore, it is very difficult to achieve a millimeter-wave band nonreciprocal device for practical use. [Solving means] To solve this problem, there is provided a millimeter-wave band nonreciprocal device composed of a magnetic material represented by a formula ?-MxFe2-xO3 (0<x<2), wherein M is at least one of elements In, Ga, Al, Sc, Cr, Sm, Yb, Ce, Ru, Rh, Ti, Co, Ni, Mn, Zn, Zr, and Y and the magnetic material having ?-phase hematite as a principal phase exhibits strong coercive force and anisotropic magnetic field at room temperature. Dimensions of a magnetic circuit containing a permanent magnet for operations of the nonreciprocal device can be made remarkably small and, by optimum design, the use of the magnetic circuit can be made unnecessary.

Abstract: A microstructure that can develop non-conventional and novel physical properties and a method for producing the same are provided. Ethanol is added to a mixture solution produced by adding a surfactant solution to a peroxotitanic acid aqueous solution to produce precipitates, and the precipitates collected from the mixture solution are let dried to produce precursor powders 5. The precursor powders 5 are calcined at a predetermined temperature. Accordingly, a microstructure 2 can be produced which is formed of monophasic Ti4O7 in nano size. The microstructure 2 of monophasic Ti4O7 produced in this fashion can be fine-grained in nano size unlike prior-art crystals.

Abstract: To provide a method for improving a coercive force of epsilon-type iron oxide particles, and an epsilon-type iron oxide. Specifically, to provide a method for improving the coercive force of an epsilon-type iron oxide comprising: substituting Fe-site of the epsilon-type iron oxide with other element, while not substituting Fe of D-site in the epsilon-type iron oxide with other element, and the epsilon type iron oxide.

Abstract: The present invention provides a process for production of a magnetic thin film which has insulation properties, serves as a permanent magnet, and has improved residual magnetization in comparison with prior arts, the magnetic thin film, and a magnetic material. When a magnetic thin film 3 is formed, an external magnetic field with a predetermined intensity is applied to a coating liquid containing magnetic particles containing epsilon-type iron-oxide-based compounds which have insulation properties and which serve as a permanent magnet, and the coating liquid is let cured in order to form the magnetic thin film 3. Accordingly, the magnetic particles containing the epsilon-type iron-oxide-based compounds can be fixed while being oriented regularly in a magnetization direction. This realizes the process for production of the magnetic thin film 3 which has insulation properties and which serve as a permanent magnet, the magnetic thin film 3, and a magnetic material 1.

Abstract: Disclosed is a magnetic material comprising a crystal of ?-GaxFe2-xO3 (wherein 0<x<1) prepared by substituting a part of Ga3+ ion sites of an ?-Fe2O3 crystal with Fe3+ ions and having X-ray diffraction peaks corresponding to the crystal structure of ?-Fe2O3. The coercive force of the magnetic material lowers in accordance with the Ga content thereof, and the saturation magnetization thereof has a maximum value.

Abstract: Disclosed is a magnetic crystal for electromagnetic wave absorbing materials, having a structure of ?-MxFe2-xO3 with 0<x<1, which has the same space group as that of an ?-Fe2O3 crystal and which is derived from an ?-Fe2O3 crystal by substituting a part of the Fe site therein with M. In this, M is a trivalent element having an effect of lowering the coercive force Hc of ?-Fe2O3 crystal by the substitution. Concretely, the element M includes Al and Ga. An electromagnetic wave absorber having a packed structure of particles having such a substituent element M-added “M-substituted ?-Fe2O3 crystal” as the magnetic phase may control the electromagnetic wave absorption peak frequency depending on the degree of substitution with the element M, and for example, the invention gives an electromagnetic wave absorber applicable to a 76 GHz band for on-vehicle radars.

Abstract: There are provided a fine structural body capable of manifesting an unprecedented property; a manufacturing method thereof; and a magnetic memory, a charge storage memory and an optical information recording medium employing such fine structural body. Unlike conventional bulk bodies phase-transited between nonmagnetic semiconductors and paramagnetic metals around about 460K, there can be provided a fine structural body 1 comprised of Ti3O5, but capable of manifesting an unprecedented property in which a paramagnetic metal property thereof is consistently maintained in all temperature ranges without undergoing phase transition to a nonmagnetic semiconductor.

Abstract: There are provided titanium oxide particles capable of manifesting an unprecedented property, a manufacturing method thereof and a magnetic memory as well as a charge storage type memory employing the titanium oxide particles. Unlike-conventional bulk bodies phase-transited between nonmagnetic semiconductors and paramagnetic metals around about 460K, provided are titanium oxide particles 3 capable of manifesting an unprecedented property that Ti3O5 particles do not undergo phase transitions at room temperature and allow a paramagnetic metal property thereof to be consistently maintained in any temperature range.

Abstract: Disclosed is a magnetic crystal for electromagnetic wave absorbing materials, having a structure of ?-MxFe2-xO3 with 0<x<1, which has the same space group as that of an ?-Fe2O3 crystal and which is derived from an ?-Fe2O3 crystal by substituting a part of the Fe site therein with M. In this, M is a trivalent element having an effect of lowering the coercive force Hc of ?-Fe2O3 crystal by the substitution. Concretely, the element M includes Al and Ga. An electromagnetic wave absorber having a packed structure of particles having such a substituent element M-added “M-substituted ?-Fe2O3 crystal” as the magnetic phase may control the electromagnetic wave absorption peak frequency depending on the degree of substitution with the element M, and for example, the invention gives an electromagnetic wave absorber applicable to a 76 GHz band for on-vehicle radars.

Abstract: A magnetic material is provided that has an iron oxide phase whose principal phase is a crystal of a structure which has the same space group as ?-Fe2O3 crystal and in which Al is substituted for a portion of the Fe sites of the ?-Fe2O3 crystal. The molar ratio of Al to Fe in the iron oxide phase, when expressed as Al:Fe=x:(2?x), satisfies 0?x?1. The value of x is preferably in the range of 0.3 to 0.7. The average particle diameter of the powder determined from a TEM image is preferably 5 to 200 nm, more preferably 10 to 100 nm. The magnetic material has very high practical value because it enables the extremely high coercive force Hc of the ?-Fe2O3 crystal to be regulated to a level enabling utilization in magnetic recording medium and various other applications. The magnetic powder can be produced by a method combining the reverse micelle method and the sol-gel method.

Abstract: Disclosed is a magnetic material having high Hc and High Curie point, which is capable of controlling such magnetic characteristics without requiring rare or expensive raw materials. Specifically disclosed is a magnetic material composed of particles of a magnetic iron oxide which is represented by the following general formula: ?-AxByFe2?x?yO3 or ?-AxByCzFe2?x?y?zO3 (wherein A, B and C each represents a metal excluding Fe and different from each other, satisfying 0<x, y, z<1), with ?-Fe2O3 as a main phase.

Abstract: A magnetic material composed of ?-InxFe2-xO3 (wherein 0<x?0.30) crystal in which In is substituted for a portion of the Fe sites of the ?-Fe2O3 crystal. The crystal exhibits an X-ray diffraction pattern similar to that of an ?-Fe2O3 crystal structure and has the same space group as that of an ?-Fe2O3. The In content imparts to the magnetic material a magnetic phase transition temperature that is lower than that of the ?-Fe2O3 and a spin reorientation temperature that is higher than that of the ?-Fe2O3. The In content can also give the magnetic material a peak temperature of the imaginary part of the complex dielectric constant that is higher than that of the ?-Fe2O3.