Abstract: A magnetic recording medium comprising a nonmagnetic support and a magnetic layer formed on the support and containing a magnetic powder and a binder, wherein said magnetic powder comprises substantially spherical or ellipsoidal particles and at least one element selected from the group consisting of rare earth elements, silicon and aluminum, and has a Fe16N2 phase, an average particle size of 5 to 30 nm and an axis ratio (a ratio of a major axis to a minor axis) of 1 to 2. This magnetic recording medium achieves a high output and has excellent short wavelength recording properties, since it uses a magnetic powder having a very small particle size and has a very high coercive force and a saturation magnetization suitable for high density recording.

Abstract: The present invention mainly provides a magnetic carrier for biological substance, which shows improved dispersibility in aqueous solutions and is superior in the collectability by the magnetic field, reversible binding ability with a biological substance, elution property of the bound biological substance, and isolation and purification efficiency of biological substance, as compared to conventional magnetic carriers. The magnetic carrier of the present invention includes a magnetic carrier having a saturation magnetization of 10-80 A·m2/kg and a coercive force of 0.80-15.92 kA/m, a magnetic carrier wherein a ferromagnetic iron oxide particle is coated with a compound comprising silicon and aluminum, and the like.

Abstract: A magnetic tape comprising a non-magnetic support, a magnetic layer containing magnetic powder which is formed on one side of the non-magnetic support, a primer layer containing non-magnetic powder which is formed between the non-magnetic support and the magnetic layer, and a backcoat layer containing non-magnetic powder which is formed on the other side of the non-magnetic support, wherein the magnetic layer contains the magnetic powder which comprises plate, granular or ellipsoidal magnetic particles with a particle diameter of 5 to 50 nm, and has a thickness of 0.09 &mgr;m or less, and wherein at least one of the primer layer and the backcoat layer contains non-magnetic plate particles with a particle diameter of 10 to 100 nm.

Abstract: A magnetic recording medium comprising a non-magnetic support; at least one lower magnetic layer containing magnetic powder and a binder resin, which is formed on one side of the non-magnetic support with or without a non-magnetic primer layer interposed between the non-magnetic support and the lower magnetic layer; at least one non-magnetic intermediate layer containing non-magnetic powder and a binder resin, which is formed on the lower magnetic layer; at least one upper magnetic layer containing magnetic powder and a binder resin, which is formed on the non-magnetic intermediate layer; and a back layer which is formed on the other side of the non-magnetic support, characterized in that the magnetic powder contained in the uppermost magnetic layer of the upper magnetic layer is iron type magnetic powder which comprises substantially spherical or ellipsoidal particles with a number-average particle diameter of 5 to 50 nm and an average axial ratio of 1 to 2, each of said particles containing iron or containi

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: The present invention provides a strikingly convenient novel purification method of protein, as compared to conventional methods, which affords automation and high throughput, and a material therefor. That is, the present invention provides a magnetic carrier containing a ferromagnetic oxide particle and a carbohydrate layer coating the ferromagnetic oxide particle, a purification method of protein using the carrier, and a reagent kit for purification of protein.

Abstract: A rare earth-iron-boron magnetic powder comprising a rare earth element, iron and boron, which has a coercive force of 80 to 400 kA/m, a saturation magnetization of 10 to 25 &mgr;W/g, an average particle size of 5 to 200 nm, and a particulate or ellipsoidal particle shape, and a magnetic recording medium having a magnetic layer which contains this magnetic powder and a binder, in which magnetic recording medium it is possible to practically use a very thin magnetic layer of 0.3 &mgr;m or less.

Abstract: Disclosed is a washing solution of a semiconductor substrate which comprises 0.0001 to 0.1% by weight of an organic acid and 0.005 to 0.25 % by weight of hydrofluoric acid and has pH of 2 to 4. When a contaminated substrate is immersed in a washing solution, a naturally oxidized film on the surface of the substrate is removed by hydrofluoric acid, and fine particles on the film, metal impurities and metal impurities in the film transfer to the liquid. Since the washing solution is an acidic solution containing an organic acid and having pH of 2 to 4, fine particles are charged to minus as those of the fine particles, and the metal impurities ions in the liquid becomes minus complex ions due to complexing effect of the organic acid. As the results, surface potentials of the respective fine particles and metal impurities are each minus which is the same as that of surface potential of the substrate so that adhesion or re-adhesion to the substrate can be prevented.

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 magnetooptical recording medium of good durability and increased reproducing output comprising a substrate and a coating type magnetic layer with a thickness of not larger than 0.5 .mu.m which is formed on the substrate and comprises a binder and a hexagonal system of ferrite particles dispersed therein, wherein a Kerr rotation angle is at least 0.3 degree when it is measured with a light having a wavelength of 830 nm under a residual magnetization condition after a magnetic field of 10 kOe is applied to the magnetic layer, and the reflectance on the surface of the magnetic layer using a light having a wavelength of 830 nm is at least 30%.

Abstract: A magnetic recording/reproducing apparatus and method, the apparatus including a drive mechanism for driving a flexible magnetic disk loaded thereon to rotate, the magnetic disk being comprised of a transparent and flexible base film formed with first and second magnetic layers on both sides thereof, each of the magnetic layers having a film thickness of no greater than 1 .mu.

Abstract: An acicular alloy base magnetic powder comprising iron and cobalt, which has an average particle long axis size of not larger than 0.25 .mu.m, an axial ratio of from 4 to 8, a cobalt content of from 8 to 50% by weight based on the weight of iron and saturation magnetization of at least 120 emu/g after being kept standing at the temperature of 60.degree. C. and relative humidity of 90% for a week, which has improved corrosion resistance and can provide a magnetic recording medium suitable for recording in the short wavelength range.

Abstract: A magnetic recording medium suitable for high density recording having improved erasing characteristics is produced by a method comprising the steps of forming an under coat layer containing an electrically conductive material on at least one surface of a substrate, applying a magnetic paint containing hexagonal system ferrite magnetic powder on the under coat layer and drying the applied magnetic paint to form a magnetic layer having a thickness of not larger than 0.7 .mu.m.

Abstract: An acicular alloy base magnetic powder comprising iron and cobalt, which has an average particle long axis size of not larger than 0.25 .mu.m, an axial ratio of from 4 to 8, a cobalt content of from 8 to 50% by weight based on the weight of iron and saturation magnetization of at least 120 emu/g after being kept standing at the temperature of 60.degree. C. and relative humidity of 90% for a week, which has improved corrosion resistance and can provide a magnetic recording medium suitable for recording in the short wavelength range.

Abstract: A magnetic recording medium which comprises a substrate and a magnetic layer comprising a hexagonal system barium ferrite powder of the formula:BaO.n[Fe.sub.2-(a+b+c+d) Co.sub.a Ni.sub.b Zn.sub.c Ti.sub.d O.sub.3+e ](I)wherein n is a number of 5.5 to 6.0, a through d are each a number of 0.01 to 0.2 and satisfy the equation:(a+b+c)/d=1 to 10and e is a number of -0.3 to 0.01, and a non-magnetic particulate powder having a Mohs' hardness of not smaller than 7 in an amount of 1 to 30% by weight based on the weight of said ferrite powder, in which demagnetization by cooling is suppressed.

Abstract: A method for producing ferromagnetic powder comprising metal oxide magnetic powder particles and a magnetic metal layer of at least one metal selected from the group consisting of iron, cobalt and nickel which layer is formed on a surface of the powder particle and has a magnetic easy axis of magnetization in substantially the same direction as that of the powder particle, which has improved coercive force and saturation magnetization, comprising irradiating with light a liquid medium dispersion containing the metal oxide magnetic particles, a reducing agent, and at least one metal ion selected from the group consisting of iron ion, cobalt iron, and nickel iron.

Abstract: A magnetic recording medium with improved durability is provided and comprises a non-magnetic substrate and a magnetic layer formed thereon containing magnetic powder of a platelet hexagonal system of ferrite particles, granular non-magnetic powder, a lubricant and a binder, the granular non-magnetic powder being contained in an amount of from 0.1 to 30 parts by weight per 100 parts by weight of the platelet hexagonal system of ferrite particles.

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 with high output power and improved durability which comprises a nonmagnetic substrate and a magnetic layer formed thereon containing magnetic powder and a binder, wherein the magnetic powder comprises a nuclear crystal consisting of magnetic oxide powder and a magnetic metallic layer formed thereon containing cobalt, and the magnetic layer has coercive force of not more than 1,000 Oe and saturation magnetic fluex density of not less than 1,800 gauss.

Abstract: A magnetic recording medium with improved durability is provided and comprises a substrate and a magnetic layer formed thereon which contains hexagonal system ferrite magnetic powder in a volume percentage of not larger than 35% per whole volume of the magnetic layer.