Abstract: A magnetic powder consisting of substantially spherical or ellipsoidal particles comprising a transition metal which comprises iron and a rear earth element which is mainly present in the outer layer of the magnetic powder particles, and having a particle size of 5 to 200 nm, a coercive force of 80 to 400 kA/m and a saturation magnetization of 10 to 25 ?Wb/g.

Abstract: A magnetic powder consisting of substantially spherical or ellipsoidal particles comprising a transition metal which comprises iron and a rear earth element which is mainly present in the outer layer of the magnetic powder particles, and having a particle size of 5 to 200 nm, a coercive force of 80 to 400 kA/m and a saturation magnetization of 10 to 25 ?Wb/g.

Abstract: A magnetic powder consisting of substantially spherical or ellipsoidal particles comprising a transition metal which comprises iron and a rear earth element which is mainly present in the outer layer of the magnetic powder particles, and having a particle size of 5 to 200 nm, a coercive force of 80 to 400 kA/m and a saturation magnetization of 10 to 25 uWb/g.

Abstract: A magnetic powder consisting of substantially spherical or ellipsoidal particles comprising a transition metal which comprises iron and a rear earth element which is mainly present in the outer layer of the magnetic powder particles, and having a particle size of 5 to 200 nm, a coercive force of 80 to 400 kA/m and a saturation magnetization of 10 to 25 &mgr;Wb/g.

Abstract: A powdery alloy mainly composed of Mn--Bi having particle diameter of 5 .mu.m or less which has a magnetic anisotropy of 6000 Oe or more in coercive force and 35 emu/g or more in saturation magnetization, wherein the size of crystallite according to Scheler's formula is 700 .ANG. or less; and an alloy containing sheet of 0.5 to 10 .mu.m thickness in which a powdery alloy mainly composed of Mn--Bi having particle diameter of 5 .mu.m or less which has a magnetic anisotropy of 6000 Oe or more in coercive force and 35 emu/g or more in saturation magnetization is bound with a binder into a sheet of 0.5 to 10 .mu.m thickness in a state magnetically oriented toward said direction of magnetic anisotropy, wherein when said sheet is measured toward said magnetic anisotropy direction at 16 kOe and 5 kOe, the ratio of residual magnetic flux density Mr16k and Mr5k (Mr5k/Mr16k) is 0.85 or more.

Abstract: The present invention relates to a lightweight and flexible material for prevention of electric waves having both absorbing properties and shielding properties against electric waves. In the present invention, carbon fiber or magnetic particles, or both and graphitized carbon black are dispersed and incorporated into an insulating substrate so that the weight ratio of the graphitized carbon black to the carbon fiber, the magnetic particles or the sum of the two may be 0.3 to 5.

Abstract: A wave absorber which is light in weight, rich in flexibility and excellent in wave absorption characteristics in a microwave frequency range. The wave absorber in which composite carbon black particles including crystalline graphite and amorphous carbon black are dispersed into an insulating matrix. In the wave absorber, dispersion of the composite carbon black particles is adjusted so that a ratio (.rho./R) of a volume resistivity .rho. measured at frequencies of 30, 100 and 500 kHz to a measured DC volume resistivity R is in a predetermined range and a volume ratio of the composite carbon black particles having particle diameters of 10 nm to 200 nm to all the composite carbon black particles is in a range of 5% to 95%. Thereby, a wave absorber excellent in absorption characteristics is obtained.

Abstract: A magnetic powder containing MnBi, in which an average particle size of the magnetic powder is from 0.1 .mu.m to 20 .mu.m; a coercive force is from 3000 to 15,000 Oe at 300 K. and 50 to 1000 Oe at 80 K. when measured with applying a magnetic field of 16 KOe; an amount of magnetization is from 20 emu/g to 60 emu/g when measured at 300 K. with applying a magnetic field of 16 KOe; a degree of decrease of an amount of magnetization is 40% or less after being maintained in an atmosphere of 60.degree. C. and 90% RH for 7 days; and a content of metal bismuth (Bi) satisfies the following equation: Metal Bi/(MnBi+metal Bi)<0.

Abstract: A magnetic recording medium comprising a substrate and a magnetic layer formed on at least one surface of the substrate, wherein magnetic powder in the magnetic layer has a degree of orientation of magnetic easy axis of the magnetization in a direction perpendicular to the magnetic layer of 0.60 or higher when measured by the Mossbauer method, has good surface smoothness, has good electromagnetic conversion properties, and is suitable for high density recording.

Abstract: A magnetic recording medium which comprises a substrate and a magnetic layer comprising hexagonal system ferrite powder of the formula:AO.multidot.n{[Fe.sub.1-(x+y) .multidot.M.sup.2+.sub.x .multidot.M.sup.4+.sub.y ].sub.2 O.sub.3 } (I)wherein,A is at least one metal selected from the group consisting of Ba, Sr, Pb and Ca,M.sup.2+ is at least one divalent metal ion selected from the group consisting of Mn, Co, Ni, Cu, Zn and Mg,M.sup.4+ is at least one tetravalent metal ion selected from the group consisting of Ti, Zr, Sn, Ge, V and Nb,n is a number of 3 to 8,x and y are such numbers that x+y is from 0.02 to 0.3 and x/y is from 0.2 to 0.8.,and which has a temperature dependency such that the coercive force of the magnetic layer is at a minimum in the temperature range of -20.degree. to 50.degree. C. and has a higher coercive force outside said temperature rangehas good storage property.

Abstract: A magnetic recording medium suitable for high density recording comprising a substrate and a magnetic layer wherein the magnetic layer comprises a binder resin and ferrite magnetic powder comprising hexagonal system plate particles having such magnetic anisotropy that a magnetic anisotropy constant K.sub.1 corresponding to the vertical magnetic component and a magnetic anisotropy constant K.sub.2 corresponding to the horizontal magnetic component, both derived from Fourier analysis of a magnetic torque curve measured in a plane including the C axis of the hexagonal system, satisfy following equations:0.5<K.sub.1 /K.sub.2 <5 and K.sub.1 >0,The magnetic recording medium is suitable for use in high density recording.

Abstract: Magnetic recording medium comprising a magnetic layer formed by magnetic powder including acicular magnetic powder with the magnetic anisotropy to be oriented perpendicular to the acicular direction which is oriented in parallel with the magnetic layer.