Hitachi Maxell, Limited

Maxell Holdings, Ltd.

Teruhisa Miyata

Akira Miyake

Masaya Funahashi

Nobuhiro Umebayashi

Kenichi Inoue

Yoshimasa Mitsumoto

Noriaki Otani

Kohji Norimatsu

Kenji Tanaka

Mikio Kishimoto

Kunio Mizushima

Yuji Yamashita

Hitoshi Nagatani

Tetsuya Taki

Yoshikazu Kai

A transparent heat-shielding/heat-insulating member having a transparent screen function of the present invention includes: an infrared reflective layer and an optical adjustment protective layer in this order from a transparent base substrate side; and a light diffusing layer on a surface of the transparent base substrate that is opposite to the surface on which the infrared reflective layer is formed or between the transparent base substrate and the infrared reflective layer. The optical adjustment protective layer includes at least a high refractive index layer and a low refractive index layer in this order from the infrared reflective layer side. The transparent heat-shielding/heat-insulating member has a visible light reflectance of 12% or more and 30% or less, a haze value of 5% or more and 35% or less, a shading coefficient of 0.69 or less, and a normal emissivity of 0.22 or less.

Transparent heat-shielding/heat-insulating member having transparent screen function

A transparent heat-shielding/heat-insulating member includes a transparent substrateand, from the transparent substrate side, an infrared reflective layerand a protective layerin this order. The protective layerincludes, from the infrared reflective layer side, a medium refractive index layer, a high refractive index layerand a low refractive index layerin this order. The medium refractive index layerhas a light refractive index at a wavelength of 550 nm of 1.45 to 1.55 and a thickness of 80 to 200 nm. The high refractive index layerhas a light refractive index at a wavelength of 550 nm of 1.65 to 1.95 and a thickness of 100 to 350 nm. The low refractive index layerhas a light refractive index at a wavelength of 550 nm of 1.30 to 1.45 and a thickness of 70 to 150 nm.

Transparent heat-shielding/heat-insulating member and production method thereof

A transparent heat-shielding member according to the present invention includes a transparent base substrate, an infrared reflective layer and a transparent screen function layer. The infrared reflective layer includes at least one selected from a metal oxide layer and a metal nitride layer, and a metal layer. The transparent screen function layer is formed of a light diffusing layer. The light diffusing layer contains light diffusing particles and a transparent resin. The light diffusing particles are dispersed in the transparent resin. The transparent heat-shielding member has a visible light reflectance measured in accordance with JIS R3106-1998 of 12% or more and 30% or less, a haze value measured in accordance with JIS K7136-2000 of 5% or more and 35% or less, and a shading coefficient measured in accordance with JIS A5759-2008 of 0.69 or less.

Transparent heat-shielding member

A near-infrared shield according to the present invention includes a base and a near-infrared absorption layer disposed on one main surface of the base. When the near-infrared shield is irradiated from the near-infrared absorption layer side with xenon light having a wavelength of 380 nm to 1200 nm at an illuminance of 60 W/m(an energy density in a range of 300 nm to 400 nm) for 16 hours under a condition of BPT of 63&#xb0; C. and a relative humidity of 50%, chromaticity changes &#x394;x, &#x394;y of transmitted light, which are shown in a chromaticity diagram of a CIE1931XYZ color system, are 0.005 or less respectively. The near-infrared shield has an excellent near-infrared shielding property and an excellent light resistance, and its near-infrared absorptivity does not deteriorate even after long-term storage.

Near-infrared shield and display front plate

A magnetic recording medium wherein thickness of the magnetic layer is less than the wavelength of projected light onto the surface of the magnetic recording medium having a multiplicity of magnetic-head tracking recesses formed thereon at predetermined intervals, and data tracks for recording thereon predetermined information provided between every two adjacent magnetic-head tracking recesses, each tracking recess and data track having a function to track a magnetic head in accordance with reflected light from the magnetic-head tracking recesses, the data tracks being provided at a track density greater than 1000 TPI and light transmittance of the magnetic recording medium is less than 5%.

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 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.

A magnetic recording medium improved in durability at an elevated 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 an ester of a polyvalent alcohol with a fatty acid in an amount of 0.01 to 40 parts by weight to one part by weight of the magnetic powder.

A magnetic recording disc having a high durability and being rotatively driven with small starting torque which comprises a non-magnetic support and a magnetic layer provided on at least one surface of the support, the magnetic layer comprising magnetic powder, a resinous binder, (a) an ester of an unsaturated fatty acid of 8 to 18 carbon atoms with a monovalent or polyvalent, saturated or unsaturated alcohol of not more than 18 carbon atoms optionally substituted with at least one alkoxy group having not more than 8 carbon atoms and (b) a fatty acid ester of the formula: ##STR1## wherein R.sub.1 is a saturated or unsaturated aliphatic hydrocarbon group having 8 to 18 carbon atoms, R.sub.2 is an alkyl group having not more than 18 carbon atoms and n is an integer of 1 or more, the combined amount of the unsaturated fatty acid ester (a) and the fatty acid ester (b) being not less than 5 parts by weight to 100 parts by weight of the magnetic powder.

A magnetic disc comprising a non-magnetic substrate, an undercoat coated on the surfaces of the substrate and a magnetic layer containing magnetic powder dispersed in a binder coated on the undercoat, characterized in that the undercoat has a thickness of from 0.5 to 10.0 .mu.m and such a porosity that a lubricant is contained therein in an amount of from 30 to 200 mg/cm.sup.3, which provides good surface lubricity and improved durability.

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Osaka, Japan

Teruhisa Miyata