Abstract: A coil encircling the ferrite core of a magnetic head attached to a slider used in a hard disk drive is formed using two mating chips. A first chip having layered wires and bonding bumps is inserted in the winding window between the ferrite core and the body of the slider. A second chip having layered wires, bonding bumps and a groove straddling the ferrite core is disposed outside the winding window and mates with the first chip. Bonding bumps, comprising low-melting solder, are heat bonded to form a continuous coil.

Abstract: The present invention provides a magnetic recording medium comprising, on a non-magnetic substrate, a magnetic layer containing magnetic fine powder and a binder, wherein the magnetic layer contains alumina powder having an average particle size of at most 1 .mu.m and containing at least one oxide of element selected from the group consisting of Ge, P, Sn, Nb, Ta, Mo and W in an amount of 0.1 to 10 parts by weight per 100 parts by weight of alumina. The magnetic recording medium of the present invention has good durability and good abrasion resistance of the magnetic layer, and good magnetic characteristics, good surface smoothness and a good cleaning effect on a magnetic head.

Abstract: Silica-alumina fibers having good mechanical strength and heat resistance are produced by mixing a polyaluminoxane which comprises repeating units of the formula: ##STR1## in which X is an alkyl group, an alkoxy group or a hydroxy group, a silicon-containing compound in an amount of not larger than 40% by weight in terms of silica based on the weight of silica-alumina fibers to be produced, and an aliphatic carboxylic acid having 2 to 14 carbon atoms in an alkyl group in an amount of 0.03 to 0.4 mole per one gram atom of aluminum to obtain a spinning liquid, spinning the spinning liquid under a condition that a content of nonvolatile materials in the solution is maintained at least 97% by weight to form precursor fibers, and calcining the precursor fibers.

Abstract: There is provided a filter element for the removal of particulates from an exhausted gas by collecting the particulates entrained with the gas characterized in that the filter element includes continuous alumina-silica fibers as inorganic fibers each of which contains not less than 98% by weight of alumina and silica and of which folding strength is not less than about 1.5 Kg/mm.sup.2.

Abstract: Translucent polycrystalline alumina made of aluminum oxide containing magnesium oxide in an amount of larger than 0.01% by weight and less than 0.03% by weight, zirconium oxide in an amount of larger than 0.01% by weight and less than 0.06% by weight and calcium oxide in an amount of less than 0.001% by weight, all based on the weight of aluminum oxide, which alumina has good light transmittance and mechanical strength.

Abstract: Alumina powder having a .theta.-alumina content of at least 70% by weight and an average primary particle size at least 0.1 .mu.m and containing a tungsten compound in an amount of 0.1 to 5% by weight in terms of tungsten oxide based on alumina can be used as an abrasive for a magnetic recording medium having good properties.

Abstract: A magnetic recording medium comprising a non-magnetic substrate and a magnetic layer which comprises magnetic powder, a binder and alumina powder having an average primary particle size of not larger than 0.3 .mu.m and containing at least one oxide selected from the group consisting of oxides of silicon, magnesium, lanthanum and zirconium in an amount of 0.05 to 5 parts by weight per 100 parts by weight of alumina, which medium has improved durability, abrasion resistance and surface smoothness of a magnetic layer and good cleaning effect on a magnetic head.

Abstract: A polishing composition for metallic materials, which comprises water, an alumina polishing agent, and a polishing accelerator, wherein the polishing accelerator is at least one selected from the group consisting of chromium(III) nitrate, lanthanum nitrate, ammonium cerium(III) nitrate, and neodymium nitrate. The polishing composition has a high polishing efficiency and provides a good surface smoothness.

Abstract: The inclination angle, in the conductor pattern end portion of a magnetic bubble memory element having a bubble diameter of up to 1.2 .mu.m, can be remarkably reduced by employing a polymer resin, having fluidity in a curing process, as the insulation film under the conductor pattern, so that the transfer margin is greatly improved.

Abstract: A hybrid magnetic bubble memory device comprising soft magnetic material propagation tracks and ion-implanted propagation tracks. In the soft magnetic material propagation track region, a layer made of a heat-resistant polymer was provided as an interlaminar insulating layer between a conductor and a pattern of a soft magnetic material. An insulator film made of a heat-resistant polymer was provided on the pattern made of a soft magnetic material. A passivation film made of an inorganic material was provided on the ion-implanted propagation tracks and the insulator film made of a heat-resistant polymer.

Abstract: When an abrasive having an oleophilic surface used in a magnetic recording medium obtained by subjecting an inorganic powder having a Mohs hardness of 5 or above and an average particle size of 2 .mu.m across or below to a dry contact treatment with a dispersing agent having an oleophilic group under grinding conditions giving an impact value of 1G or greater is used in combination with a magnetic powder as a magnetic recording layer of magnetic recording medium, the wear at a magnetic head can be prevented and still characteristics can be improved.

Abstract: A method for producing .gamma.-form lithium aluminate powders usable as a material for an electrolyte tile of molten carbonate fuel cells which comprises mixing aluminum alkoxide with one member selected from the group consisting of the lithium salts of inorganic and organic acids, lithium hydroxide and lithium oxide in the presence of a non-aqueous solvent, carrying out reaction with addition of water of 1.5 to 20 moles (including water of crystallization contained in the lithium compound) based on 1 mole of aluminum alkoxide with stirring, and removing the solvent to obtain a solid matter which is then calcined at a temperature in a range of from 650.degree. C. to 1000.degree. C.

Abstract: A magnetic recording medium comprising a substrate and a magnetic layer formed on the substrate and comprising an inorganic powder having an average primary particle size of 0.35 .mu.m or less, an angle of repose of 40.degree. or more and a Mors hardness of 5 or more as a reinforcing material, and a magnetic powder, is excellent in wear resistance and durability of the magnetic layer and improves wear and injury of a magnetic head.

Abstract: High purity organometallic compounds can be obtained by the process which comprises subjecting an organometallic compound in a liquid state under stirring to preliminary oxidation or hydrolysis in a proportion of about 0.1 to 50% by weight of the organometallic compound to form solid reaction products, and separating by distillation the unreacted organometallic compound from the solid reaction products to recover the purified organometallic compound; and high purity metallic compounds such as a solid metallic hydroxide or oxide can be obtained by the process which comprises following the process as mentioned above, oxidizing or hydrolyzing completely the recovered purified organometallic compound.

Abstract: When an abrasive having an oleophilic surface used in a magnetic recording medium obtained by subjecting an inorganic powder having a Mohs hardness of 5 or above and an average particle size of 2 .mu.m across or below to a dry contact treatment with a dispersing agent having an oleophilic group under grinding conditions giving an impact value of 1 G or greater is used in combination with a magnetic powder as a magnetic recording layer of magnetic recording medium, the wear at a magnetic head can be prevented and still characteristics can be improved.

Abstract: A magnetic bubble memory device is disclosed which is equipped with a minor loop of a magnetic bubble propagation track formed by ion implantation and a major loop or major line of a magnetic bubble propagation track consisting of a soft magnetic film and in which the thickness of an insulating film at at least the junction between the minor loop and the major loop or major line is less than the thickness of insulating film at the major line or major loop.

Abstract: A method of fabricating a magnetic bubble memory device is disclosed in which ions are implanted in a desired portion of a surface region in a magnetic bubble film for magnetic bubbles to form a strain layer having a strain of about 1% to about 2.5%, a film is provided on the magnetic bubble film so as to cover the magnetic bubble film with the film and then the magnetic bubble film is annealed under predetermined conditions, thereby providing a practical magnetic bubble memory device having a large bias margin.

Abstract: Fine patterns are formed by a process wherein a workpiece is spin coated with a heat-resistant resin layer, this resin layer is spin coated with an organotitanium or titanium oxide layer, a resist pattern is formed on the organotitanium or titanium oxide layer, the organotitanium or titanium oxide layer is etched by ion etching with the resist pattern as a mask, and finally, the resin layer is etched by using the etched organotitanium or titanium oxide layer as a mask.

Abstract: A magnetic bubble memory device comprises an ion-implanted region for information storage formed in a surface of a magnetic material layer and a permalloy transfer path formed near an ion implantation transfer path defined by the edge of the ion-implanted region for reading information from the ion implantation transfer path or writing information in the ion implantation transfer path. The ion implantation depth in a portion of the ion-implanted region near the permalloy transfer path is continuously changed to provide an inclined edge of the ion-implanted region.

Abstract: Pigmented aluminum oxide powders are provided herein obtained by adding at least 0.5 wt. % of carbon black to aluminum oxide powder, said carbon black having a mean particle size of less than about 100 mn and a specific surface area more than 30 m.sup.2 /g, and mixing the aluminum oxide powder-carbon black composition under an impact value of more than 1 G, preferably by use of a vibration mill. The present invention also provides a method of producing said pigmented aluminum oxide powder.