Hitachi, Ltd.

Hisashi Morooka

Kenji Ikeda

Yutaka Ito

Keiji Suzuki

Shuji Imazeki

Takayuki Nakakawaji

Mitsuru Onoda

Hiroshi Sasaki

Hiroyuki Matsumoto

Yoshitaka Takezawa

Tsutomu Kono

Tomoyuki Hamada

Tetsuya Hamaguchi

Heigo Ishihara

Motonobu Iizuka

Nobuaki Tanaka

Akira Yamagishi

Kenichi Kawamura

Juichi Arai

Kohhei Aida

Hiroaki Kojima

Mitsuyoshi Shoji

Mitsuyoshi Shouji

Yasuaki Kageyama

Hiroki Nakatsuchi

Kazuo Goto

Tomoe Takamura

Shoichi Maruyama

Masaki Akatsuka

Naohiro Hiruta

Yuko Murakami

Yoshihiro Haraguchi

Yuko Morita

Electrical insulating paper according to an embodiment of the present invention is used while being immersed in electrical insulating oil, and includes a paper base material mainly containing cellulose, an adsorption layer formed on an entire surface of the paper base material by adsorption, and a moisture barrier layer formed by being chemically bonded to the adsorption layer. The moisture barrier layer includes an amphipathic molecule containing both a hydrophobic hydrocarbon group and a hydrophilic functional group in one molecule. The amphipathic molecule is chemically bonded to the adsorption layer via the hydrophilic functional group. The hydrophobic hydrocarbon group covers the surface of the paper base material.

Electrical insulating paper and stationary induction electrical apparatus using the same

A dry mica tape includes a base material, a binder resin layer A formed on the base material and including an epoxy resin and an accelerator, a mica paper layer formed in contact with the binder resin layer A, and a binder resin layer B formed in contact with the mica paper layer, including an epoxy resin, and providing a cured resin with a higher glass transition point than that of a cured resin of an impregnating varnish only by reacting with an impregnating varnish including an epoxy resin impregnated into the dry mica tape wound around a conductor.

Dry mica tape and insulation coils manufactured therewith

The present method aims at preventing breakdown by selecting conditions for preventing the occurrence of voids via analysis. According to the present method, a database related to the time variation of amount of generated gas or number of moles when a solid member is heated is experimentally formulated in advance, and the amount of generated gas from the member and the specific heat ratio of gases are entered for analysis in order to predict via analysis the generation of voids within the resin material when the solid member is heated, to thereby select conditions for preventing voids.

Method for predicting volume change of void generated in resin filled in porous body, and method for analyzing flow of resin material in porous body

The present invention is designed to provide an insulation coil with high insulation reliability using a dry mica tape, an integral impregnation coil and a mica tape for the electrical rotating machines using these coils, said mica tape having a long shelf life and capable of preventing run-off of the impregnating epoxy resin composition during curing, with the cured product of said epoxy resin composition being high in heat resistance. It is also envisaged to provide a single insulation coil using a mica tape containing epoxy adduct imidazole as an epoxy resin curing catalyst or a mica tape containing a mixture of epoxy adduct imidazole and zinc naphthenate. An integral impregnation coil made by using said insulation coil and an epoxy resin composition, and the electrical rotating machines using such coils are also provided.

Winding applied single vacuum pressure impregnation insulation system, a winding applied global vacuum pressure impregnation insulation system and an electrical rotating machine having said insulation systems

An epoxy resin that contains, in a molecule, two mesogens coupled by a folded chain, is provided using a method that ensures easy synthesis of such an epoxy resin, and a uniform epoxy resin composition is provided based on this epoxy resin. The epoxy resin includes a major compound having a structure expressed by the Chemical Formula (1), and a method is provided for manufacturing the epoxy resin by reaction of (A) an epoxy resin with one mesogen contained in a molecule and (B) a compound with two elements of active hydrogen contained in a molecule, with the percentage composition of (B) active hydrogen with respect to (A) epoxy group being 0.25 and over, up to and including 0.7.

Epoxy resin, epoxy resin composition, cured epoxy resin, and manufacturing method thereof

A magnetic recording medium comprising a non-magnetic substrate and a magnetic layer and a protective layer which are formed on the non-magnetic substrate in that order, wherein a substance(s) as a single component or a plurality of components, which constitute a liquid continuously supplied to the surface of said protective layer, are adsorbed on or react with the surface of said protective layer to form a lubricating film having low frictional properties and low wearing-out properties. The present invention can realize negligible friction and wear resistance even in severe sliding at a very slightly kept-off or completely contacted state by continuous supply of a liquid lubricant prepared by adding a fluoro compound and an extreme pressure agent or an oiliness agent to a solvent to the surface of a disc, and can provide a magnetic recording reproducer having excellent sliding-resistant characteristics.

Magnetic recording medium and magnetic recording reproducer

The present invention is aimed at providing a magnetic disk and a magnetic disk apparatus both of which have a high performance lubricating film which makes continuous sliding endurance and low adhesiveness compatible, and a lubricating film having a self repairing function which makes it possible to recombine scratched off lubricating agent from the magnetic disk surface by sliding with a head onto the magnetic disk surface. The lubricating film comprises at least two kinds of lubricating agents each of which forms an individual layer, the layers being laminated. An adhesion enhancing layer is formed between a magnetic film and a lubricating agent at the surface of the magnetic disk, and the adhesion enhancing layer is fixed onto the magnetic film surface. Then, the adhesion enhancing layer and the lubricating agent are combined. The adhesion enhancing layer and the lubricating agent form a salt or complex body, and the lubricating agent can repeat adsorption and desorption with the adhesion enhancing layer reversely by a thermal reaction.

Magnetic disk, and magnetic disk apparatus

Growing community of inventors

Hitachinaka, Japan

Hisashi Morooka