Hitachi Maxell, Limited

Kuraray Chemical Co., Ltd.

Akira Miyake

Teruhisa Miyata

Masaya Funahashi

Kenichi Inoue

Mikio Kishimoto

Nobuhiro Umebayashi

Kunio Mizushima

Tsugihiro Doi

Akito Sakemoto

Toshinobu Sueyoshi

Seiichi Asada

Hitoshi Nagatani

Kohji Norimatsu

Kenji Tanaka

Hideo Fujiwara

Takayuki Yamada

Seigi Kawarai

Tetsuya Hanamoto

Yoshinori Yamamoto

Kenichi Yokoyama

Masahiro Amemiya

Yoshifumi Egawa

Susumu Abe

Takanori Kitamura

Shizuo Ishimura

Norio Akai

Tomizo Taniguchi

Masakazu Oshimura

Yukihiro Hayashi

Minoru Ezoe

Akira Ohtani

Yoshikazu Kai

The present invention provides an evaporated fuel gas adsorbent, an evaporated fuel gas trapping apparatus that uses the adsorbent, an activated carbon, and a process for producing the activated carbon. The evaporated fuel gas adsorbent is capable of improving adsorptivity and desorptivity by reliably preventing a temperature rise and a temperature fall caused by heat generated in response to the adsorption and desorption of evaporated fuel gas, is capable of achieving a size reduction of the device, and is capable of being easily produced. The activated carbon has high mechanical strength and high abrasive resistance, has many pores suitable to adsorb an organic solvent, especially, evaporated fuel gas, and has a high packing density. The activated-carbon producing process is industrially advantageous.

Evaporated fuel gas adsorbent, evaporated fuel gas trapping apparatus, active carbon and process for producing the same

Magnetic recording medium

A magnetic disk has optical servo grooves formed at specified intervals along data tracks so that variations in reflected light of light applied to the grooves are detected so as to allow a magnetic head to perform tracking servo. A level difference between a regenerative signal and a fundamental wave of modulation noise during reads of data recorded on the data tracks (4A, 4B) is set to 28 dB or more. Thus, comb-shaped modulation in a regenerative signal due to optical servo grooves is reduced so that output drop of the regenerative signal is suppressed and deterioration of window margin and the like is lessened.

Magnetic disk which reduces deterioration in regenerated signals due to

A magnetic disc cartridge comprising a cartridge case, a magnetic disc housed rotatably in the cartridge case, and a liner, which serves as a cleaning sheet, secured on the inner surface of the cartridge case, characterized in that the magnetic disc has a magnetic layer containing a ferromagnetic metal powder, a reinforcing powder, whose content is defined in the range of from 5 to 40% by weight, and a fatty acid ester with a melting point of 0.degree. C. or lower, and that at least the disc side surface layer of the cleaning sheet, which is brought into sliding contact directly with the magnetic layer, is almost entirely composed of rayon fiber, such that the magnetic disc cartridge of the present invention can provide a highly reliable magnetic disc cartridge having a magnetic disc which is excellent in durability and substantially error free.

Magnetic disc cartridge including a magnetic disc having a cleaning

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.

A magnetic disc comprising a nonmagnetic substrate made of a synthetic resin film and at least one magnetic layer on the surface of the substrate has improved reliability when it having a dimensional shrinkage factor of not more than 0.04% in a radial direction after keeping the magnetic disc at 60.degree. C., 90% RH for 64 hours and then keeping it at room temperature for 72 hours.

Flexible magnetic disc

A magnetic disc with good abrasion resistance and improved durability, which comprises a non-magnetic substrate, a magnetic layer comprising a metal magnetic powder formed on one side of the substrate and a coating comprising an inorganic powder having a Mohs hardness of not less than 4 formed on the other, back side of the substrate, which has good abrasion resistance and improved durability.

Magnetic disc

A magnetic recording medium comprising a non-magnetic substrate, a primer coating formed on the substrate and comprising an organic conducting polymer and a magnetic layer formed on the primer coating, which has good surface smoothness and low surface resistance.

Magnetic recording medium comprising a substrate coated with a primer

A magnetic recording medium with improved output characteristics and durability is provided by using magnetic powder comprising iron-containing particles each of which carries a compound containing aluminum and/or a compound containing silicon in such amounts that, in the whole magnetic powder, a weight ratio of silicon to iron is from 0.010:1 to 0.150:1, a weight ratio of aluminum to iron is from 0.040:1 to 0.150:1, and a weight ratio of aluminum to silicon is from 1:1 to 15:1.

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.

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.

Magnetic powder at least a part of particles of which have surface-adjacent layers comprising an aluminium-containing oxide of the corundum structure has high hardness so that a magnetic recording medium comprising a magnetic layer containing such magnetic powder has improved durability.

Magnetic powder and magnetic recording medium comprising the same

A magnetic disc which comprises a non-magnetic support substrate and a magnetic layer thereon consisting of a magnetic coating comprising ferromagnetic powder, a binder, an aliphatic acid ester having a melting point not higher than 10.degree. C. and an aliphatic acid ester having a melting point from 15.degree. to 60.degree. C., the magnetic coating having improved lubricity and durability.

A magnetic recording medium improved in durability over a wide range of temperature which comprises a substrate and a magnetic layer comprising magnetic powder and a resinous binder formed on the substrate, characterized in that the magnetic layer further comprises a monovalent alcohol ester of a fatty acid and a straight chain saturated fatty acid ester of not less than 28 carbon atoms in a weight proportion of 99:1 to 1:99 in a combined amount of 0.1 to 20 percent by weight based on the weight of the magnetic powder.

A magnetic recording disc having a high durability and good electromagnetic conversion characteristics which comprises a non-magnetic support and a magnetic layer provided on at least one surface of the support, wherein the magnetic layer comprises magnetic powder, a resinous binder, polishing particles and a lubricating agent, characterized in that the polishing particles have a Mohs' scale of hardness of not less than 7 and an average particle size of 0.25 r to 0.75 r (r being the thickness (.mu.m) of the magnetic layer) and the lubricating agent is a fatty acid ester having a melting point of not higher than 10.degree. C.

Growing community of inventors

Osaka, Japan

Akira Miyake