There are provided an oriented body such as a magnetic sheet in which a value of degree of orientation of magnetic particles is beyond 3.5, and a method for producing the same, and a device for producing the same, wherein the oriented body such as a magnetic sheet is produced through the steps of: mixing a mixed solution containing a solvent and a vehicle and ε-iron oxide particles by shaking stirring, and dispersing the ε-iron oxide particles in the mixed solution; providing a mixed solution in which the ε-iron oxide particles are dispersed, on a predetermined substrate; and removing the solvent while applying a magnetic field to the substrate provided with the mixed solution, to obtain an oriented body.

There are provided an oriented body such as a magnetic sheet in which a value of degree of orientation of magnetic particles is beyond 3.5, and a method for producing the same, and a device for producing the same, wherein the oriented body such as a magnetic sheet is produced through the steps of: mixing a mixed solution containing a solvent and a vehicle and ε-iron oxide particles by shaking stirring, and dispersing the ε-iron oxide particles in the mixed solution; providing a mixed solution in which the ε-iron oxide particles are dispersed, on a predetermined substrate; and removing the solvent while applying a magnetic field to the substrate provided with the mixed solution, to obtain an oriented body.

There is provided a ferrite powder for bonded magnets capable of producing ferrite bonded magnets with high BH.sub.max, excellent in MFR when converted to a compound, with high p-iHc, wherein an average particle size of particles obtained by a dry laser diffraction measurement is 5 μm or less, a specific surface area is 1.90 m.sup.2/g or more and less than 3.00 m.sup.2/g, a compression density is 3.40 g/cm.sup.3 or more and less than 3.73 g/cm.sup.3, and a compressed molding has a coercive force of 2800 Oe or more and less than 3250 Oe.

There is provided a ferrite powder for bonded magnets capable of producing ferrite bonded magnets with high BH.sub.max, excellent in MFR when converted to a compound, with high p-iHc, wherein an average particle size of particles obtained by a dry laser diffraction measurement is 5 μm or less, a specific surface area is 1.90 m.sup.2/g or more and less than 3.00 m.sup.2/g, a compression density is 3.40 g/cm.sup.3 or more and less than 3.73 g/cm.sup.3, and a compressed molding has a coercive force of 2800 Oe or more and less than 3250 Oe.

A manufacturing method for a bonded magnet, in particular a manufacturing method for an anisotropic bonded magnet. The present invention solves the problem that the existing manufacturing method under the condition of heating magnetic powders performs magnetic field orientation after a binder is melted, resulting in low production efficiency, a complicated mould structure, high process costs, thereby affecting wide use of an anisotropic bonded magnet. A manufacturing method for an anisotropic bonded magnet comprising the following steps: 1) mixing anisotropic magnetic powders and a thermosetting binder; 2) adding the mixture of step 1) to a mould cavity, performing pressure forming under an oriented magnetic field, and performing demagnetization, so as to obtain a green body; and 3) loading the green body of step 2) into a vacuum furnace for thermal curing, so as to obtain an anisotropic bonded magnet. In the present application, forming is performed in a magnetic field at normal temperature or in a cold state, avoiding magnetic powders being bonded to each other, improving the effect of magnetic field orientation, and the mould has a simple structure, is easy to operate, and provides high efficiency, thereby lowering cost.

The magnetic tape includes a non-magnetic support; a magnetic layer including ferromagnetic powder and a binding agent on one surface side of the non-magnetic support; and a back coating layer including non-magnetic powder and a binding agent on the other surface side of the non-magnetic support, in which an isoelectric point of a surface zeta potential of the magnetic layer is equal to or smaller than 3.8, and an isoelectric point of a surface zeta potential of the back coating layer is equal to or smaller than 3.0, a magnetic tape cartridge, and a magnetic tape apparatus including this magnetic tape.

A ferrite powder for bonded magnets capable of producing a ferrite bonded magnet having high BH.sub.max, and excellent in fluidity when converted to a compound, and having a high p-iHc value, and a method for producing the same, and a ferrite bonded magnet using the ferrite powder for bonded magnets, wherein an average particle size of particles obtained by a dry laser diffraction measurement is 5 μm or less; a specific surface area is 1.90 m.sup.2/g or more and less than 2.80 m.sup.2/g; a compression density is 3.50 g/cm.sup.3 or more and less than 3.78 g/cm.sup.3, and a compressed molding has a coercive force of 2300 Oe or more and less than 2800 Oe.

Compositions including hard magnetic photoresists, soft photoresists, hard magnetic elastomers and soft magnetic elastomers are provided.

A ferrite powder for bonded magnets having a high iHc value usable even in a low temperature environment, a method for producing the same, and a bonded magnet using the ferrite powder and having high iHc value which can be used even in a low temperature environment, wherein a specific surface area is 2.20 m.sup.2/g or more and less than 3.20 m.sup.2/g; a compression density is 3.30 g/cm.sup.3 or more and less than 3.60 g/cm.sup.3, and a compressed molding has a coercive force of 3250 Oe or more and less than 3800 Oe.

The magnetic tape includes a non-magnetic support; a magnetic layer including ferromagnetic powder and a binding agent on one surface side of the non-magnetic support; and a back coating layer including non-magnetic powder and a binding agent on the other surface side of the non-magnetic support, in which an isoelectric point of a surface zeta potential of the magnetic layer is equal to or smaller than 3.8, and an isoelectric point of a surface zeta potential of the back coating layer is equal to or smaller than 3.0, a magnetic tape cartridge, and a magnetic tape apparatus including this magnetic tape.