Abstract: In a magnetic head comprising a first and second core halves bonded together defining a magnetic gap, an non-magnetic thin layer is formed on the surface of each core half facing to the magnetic gap using materials which are substantially chemically non-reactive with the component of an amorphous metallic magnetic thin layer of each half and low melting point glass, and low melting point glass thin layer formed on the non-magnetic thin layer made of glass having a melting of point of temperature lower than the crystallization temperature of the amorphous metallic magnetic thin layer.

Abstract: In a recording tape cartridge having a cartridge case, magnetic recording tape and a front lid and a rear lid for protecting the magnetic tape, there are provided entrance preventing members at a bottom the cartridge case facing to clearances between side edges of the front lid and case body for preventing entrance of harmful floating particles into the area near the recording tape so as to prevent corrosion of the recording tape.

Abstract: In manufacturing a magnetic head having a magnetic circuit formed of magnetic material in which anisotropy can be induced, the magnetic head is processed by a first annealing process in a magnetic field for inducing anisotropy to generate an axis of easy magnetization in one direction in a part of the magnetic material, subsequently the magnetic head is processed by a second annealing process for annealing the magnetic material, applying the magnetic field in one of the directions perpendicular to the axis of the easy magnetization so as to relax the anisotropy induced by the first annealing process.

Abstract: A magnetic recording medium suitable for high density recording comprising a non-magnetic substrate and a magnetic layer which contains a non-magnetic binder and ferromagnetic powder dispersed therein formed on said substrate, the coercive force of the magnetic layer being from 1,400 to 2,000 oersteds, the residual magnetic flux density being at least 1,100 gausses and a thickness of the layer being at least 0.5 .mu.m, which effectively works when it is used together with a magnetic head, a part of which near a magnetic gap, made of a magnetic material having saturation magnetic flux density of at least 7,000 gausses and which has a magnetic gap length of 0.15 to 0.4 .mu.m.

Abstract: A magnetic head apparatus used for a movable magnetic medium, comprising a magnetic head core in which a recording/reproducing core and an erasing core are respectively disposed on the entrance side of the movable medium and on the exit side of the movable medium, both of the cores being formed as an integrated magnetic core. The head cap of the recording/reproducing core is placed within a range defined between a position spaced about 0% of the longitudinal length of the integrated magnetic core apart from the center of the magnetic core toward the entrance side of the movable medium and another position spaced about 20% of the longitudinal length of the integrated magnetic core apart from the center toward the exit side of the movable medium.

Abstract: A magnetic head having a first core half body constituted by a first non-magnetic base and a magnetic layer made of a high-permeability magnetic material and formed on the first non-magnetic base, and a second core half body constituted by a second non-magnetic base and a magnetic layer made of a high-permeability magnetic material and formed on the second non-magnetic base. This magnetic head is provided with a track width regulation groove communicating with at least one of recording medium sliding surfaces of the first and second non-magnetic bases, the track width regulation groove being filled with the magnetic layer; and abutting surfaces formed on the sides of the track width regulation groove opposite to each other in the widthwise direction of the track, the abutting surfaces being parallel to the surface of mating one of the first and second core half bodies when the abutting surfaces abut there-against.

Abstract: A magnetic recording medium which comprises a non-magnetic substrate, a magnetic film formed on the substrate and a protective film provided on the magnetic film, the protective film being composed of at least two groups of element, the element in one group being at least one of B and C having a smaller atomic size, and a concentration of the element increasing from the interface side of the protective film with the magnetic film toward the opposite face side throughout the protective film has an improved durability against a magnetic head.

Abstract: A magnetic recording medium comprising a non-magnetic substrate, a soft magnetic layer formed thereon, and a perpendicularly magnetizable layer formed on the soft magnetic layer, where at least the soft magnetic layer is a vapor deposited mixture layer composed of an organic material and a ferromagnetic material, has distinguished flexibility and durability.

Abstract: In a magnetic head with a slider, there are provided a head core made of a magnetic material having a first sliding surface for slidably contacting with a magnetic recording medium and at least one recording and reproducing gap defined on the sliding surface, a slider having a second sliding surface for slidably guiding the magnetic recording medium. The slider is connected to one side wall of the magnetic head core by an adhering material. A recess is defined on the slider along the entire length of the peripheral portion of one side wall of the magnetic head core. Chamferred parts are formed on the corner of the first sliding surface and the side wall of the magnetic head core.

Abstract: In a magnetic head carriage assembly which includes a head carriage for mounting a magnetic head for slidably contacting with a rotating magnetic disc and a clamper for mounting a clamp shoe disposed to oppose the magnetic head and biased toward the head carriage, there is provided a pivot for confining the movement of the clamp shoe in a direction perpendicular to the direction of rotational plane of the magnetic disc and a cantilever spring for mounting the magnetic head on the carriage or clamper.

Abstract: The present invention relates to a magnetic head, which can form guard bands on a magnetic recording medium and which is especially suitable for magnetic discs, and a fabrication process thereof. The magnetic core of the present invention includes a recording and reproduction head core (31) and an erasure head core (32) which is integrally joined in series to the head core (31) for forming guard bands. Magnetic circuits are constructed of metallic magnetic materials (34), (34'), (35) and (35') formed on non-magnetic members (33) and (33'). As a result, a recording medium having high coercive forces can be recorded while the track width is reduced and the fabrication is facilitated with a high accuracy.

Abstract: A composite type magnetic head wherein a functional gap is formed by a pair of opposing magnetic metal substance members coupled to a substrate of a nonmagnetic substance and include a head front surface facing a magnetic recording medium. A coil portion is provided rearwardly of the head front surface and includes a coil window provided between the pair of magnetic metal substance members and a coil for encircling both the nonmagnetic substance substrate and at least one of the magnetic metal substance members coupled to the substrate. A rear core portion is provided rearwardly of the coil portion and is magnetically coupled with the magnetic metal substance members, the rear core portion including at least a part made of a high permeability ferrite.

Abstract: A magnetic head having a pair of core halves each combined through a magnetic gap, each of the core halves comprising a core base having slanted side surfaces on the side opposing to the magnetic gap and a magnetic thin layer formed on the surfaces of the core base on the side opposing the magnetic gap with magnetic material of high saturation magnetic flux density, the minimum value of the sum of products of vertical cross sectional areas of the respective magnetic paths of each of the core halves except for the path of the magnetic gap and the respective saturation magnetic flux densities of the respective parts is greater than the product of the area of the magnetic gap and the saturation magnetic flux density of the magnetic thin layer.

Abstract: There is provided a structure of a composite type magnetic head and its manufacturing method. The composite type magnetic head comprises: two high permeability ferrite blocks with projections having nearly edged sections formed thereon; magnetic films having a high saturation flux density deposited on the side faces of the projections, the magnetic films confronting each other via a functional gap near front ends of said projections; guard films deposited over the magnetic films comprising a non-magnetic material; and non-magnetic materials filled on the guard films up to side face of the coil. This magnetic head exhibits excellent recording and reproducing characteristics. The contour effect is negligibly small. The reaction between the magnetic film and the non-magnetic material is prevented by the guard film.

Abstract: A thin-film magnetic head which has a structure wherein a spiral conductor coil having a plurality of turns is disposed between first and second magnetic layers being substantially in parallel with each other, through upper and lower inorganic insulator layers, and in which a part of the outermost turn of the conductor coil is exposed on a face opposite a magnetic recording medium along with the upper and lower inorganic insulator layers, to form a magnetic gap. This head can be readily manufactured by a manufacturing method including the step of forming the outermost turn of the conductor coil on the side of the face opposite the magnetic recording medium so as to be wider than any other part of the conductor coil, and the step of thereafter machining the face opposite the magnetic recording medium so as to expose the outermost turn of the conductor coil on the face opposite the magnetic recording medium.

Abstract: A perpendicular magnetic recording and reproducing thin film head of a structure excellent in magnetic characteristics and easy of fabrication, wherein a lower magnetic layer disposed on a flat nonmagnetic substrate is used as a main magnetic pole, a first insulator layer is formed on the main magnetic pole, a conductor for a coil and a second insulator layer are disposed on the first insulator layer, and an upper magnetic layer which lies in contact with the lower magnetic layer through the first insulator layer at one end thereof and directly at the other end thereof and which overlies the second insulator layer in a part thereof other than both the ends is disposed and used as an auxiliary magnetic pole.

Abstract: A magnetic recording and reproducing system comprising (i) a magnetic head including a first magnetic pole whose saturation flux density is at least 7 kG and whose edge face is 0.15-0.5 .mu.m thick, and a second magnetic pole which lies on the same side as the first magnetic pole with respect to a recording medium and whose edge face is at least 10 times thicker than that of the first magnetic pole, and (ii) the perpendicular magnetic recording medium including a perpendicular magnetization layer which has a coercive force of 250-600 Oe. in a direction perpendicular to a plane thereof and which is 0.1-0.5 .mu.m thick.

Abstract: A perpendicular magnetic recording medium free from spike noise having a high permeability magnetic material film, an antiferromagnetic material film and a perpendicularly oriented magnetic material film formed on a substrate in this order. Another high permeability magnetic material film may be formed between the antiferromagnetic material film and the perpendicularly oriented magnetic material film. During the formation of the antiferromagnetic material film, a magnetic field is applied in a direction of a track width.

Abstract: A composition for pneumatic tires including more than 30% of star shaped styrene-butadiene copolymers by solution polymerization with or without one or more types of natural rubbers or diene series synthetic rubbers. The composition value X of the solution polymerization star shaped SBR is obtained by the following equation. ##EQU1## wherein BR is the butadiene component and the vinyl content is the content of 1, 2 bonded butadiene in butadiene component. The value X falls in the range of the lower limit of 26 to the upper limit of 39. And the coupling efficiency of the solution polymerization star shaped SBR is more than 40%.

Abstract: A magnetic film structure comprises at least one magnetic film unit wherein a plurality of main magnetic films of 0.05 to 0.5 .mu.m thickness made of a magnetic alloy containing iron or cobalt as principal constituent and having a high saturation magnetic induction of 10,000 gauss or more and a magnetostriction of 10.sup.-6 or less are laminated through intermediate magnetic films made of a magnetic material such as a nickel and iron alloy or amorphous magnetic alloy different from that of the main magnetic film and being so thin that the influence of coercive force of the intermediate magnetic film does not come out. A plurality of the magnetic film units are also laminated through non-magnetic insulating films. The magnetic film structure has high saturation magnetic induction and low coercive force.