Hitachi Metals, Ltd.

Hitachi Magnet Wire Corp.

Hitachi Cable, Inc.

Sumitomo Seika Chemicals Co., Ltd.

Namco Limited

Hide Technology, LLC

Hideyuki Kikuchi

Yuki Honda

Tomiya Abe

Shuta Nabeshima

Yuzo Yukimori

Takami Ushiwata

Hidehito Hanawa

Daisuke Hino

Yasuhiro Funayama

Yuji Takano

Takanori Yamazaki

Kiyoshi Watanabe

Takahiko Hanada

Naofumi Chiwata

Kenji Asano

Yosuke Sumi

Noriyuki Hayashizaka

Masashi Arai

Seiji Bando

Akira Setogawa

Yoshiyuki Tetsu

Junichi Abe

Yasushi Omori

Yutaka Kounoe

There is provided a laminate having excellent partial discharge resistance. A laminate of a conductor and an insulating coating comprising a conductor and an insulating coating formed on the conductor, wherein the insulating coating is formed of a resin composition containing a metal oxide hydrate, and an inorganic insulating layer is formed on the insulating coating when the laminate is exposed to partial discharge caused by inverter surges.

Laminate of conductor and insulating coating, coil, rotating electric machine, insulating paint, and insulating film

An insulated wire includes a conductor, a first insulation coating layer which is provided directly on the conductor and includes a polyamide-imide resin including dispersed inorganic fine particles, and a second insulation coating layer which is provided on the outer circumference of the first insulation coating layer and includes a polyamide-imide resin or a polyimide resin. A minimum winding multiplied diameter that does not cause a crack in the first insulation coating layer when the insulated wire is elongated by 30% by a method in compliance with JISC 3216 '5.1.1' and is wound around a winding bar is greater than 2d but smaller than 4d (where d is a conductor diameter of the insulated wire).

Insulated wire and winding

An insulated wire includes a conductor and an insulating layer formed on an outer periphery of the conductor, and the insulating layer is composed essentially of a polyimide resin having a repeating unit A represented by Formula (1) as a part of a molecular structure, in which a water absorption coefficient is not greater than 2.8% after 24 hours under condition at temperature of 40&#xb0; C. and humidity of 95%. 

Insulated wire and coil using same

An insulated wire includes a conductor, and a polyimide insulation layer formed on an outer periphery of the conductor. The insulation layer includes a polyimide including a repeating unit represented by formula (1) and a repeating unit represented by formula (2). A first acid component in the repeating unit represented by the formula (1) and a second acid component in the repeating unit represented by the formula (2) are mixed in a molar ratio range of 85:15 to 40:60 as expressed by a molar ratio (the first acid component:the second acid component). R as a residue of a diamine component in the formulas (1) and (2) includes a residue of 4,4'-diaminodiphenyl ether and a residue of one selected from a group of diamines represented by the formulas (3) to (8). A storage elastic modulus of the polyimide at 325&#xb0; C. is not less than 50 MPa.

Insulated wire and coil using the same

An insulated electric wire includes a rectangular conductor and an insulation film disposed on the periphery of the rectangular conductor. The insulation film is characterized by: the provision of a resin containing an imide structure within a molecule; and a peak value of less than 1.0 for the loss tangent tan &#x3b4;, which is represented by the ratio between the loss elastic modulus and the storage elastic modulus, as measured in the 50 DEG C. to 400 DEG C. range.

Insulated electric wire and coil

A partial discharge charge amount measuring method includes generating a partial discharge in a sample by applying a voltage from a voltage impressing device connected to the sample, the voltage being higher than a partial discharge inception voltage, continuously measuring and recording terminal voltages of a capacitor connected in series between the sample and a ground at least until a breakdown of the sample occurs by alternately operating at least two data loggers connected to the capacitor at intervals of a predetermined time, calculating an amount of electric charge discharged from the sample and remaining in the capacitor by multiplying a difference in the recorded terminal voltages of the capacitor by a capacitance of the capacitor, and calculating an accumulated discharge amount by accumulating the discharged amount of electric charge at earliest until the breakdown of the sample occurs.

Partial discharge charge amount measuring method and device

An insulated electric wire includes a conductor and an insulating coating provided around a perimeter of the conductor. The insulating coating includes a first insulating coating film around the perimeter of the conductor, the first insulating coating film being formed of a resin containing an imide structure in its molecule, and a second insulating coating film around a perimeter of the first insulating coating film, the second insulating coating film being formed of a polyimide resin comprising a repeat unit represented by Formula 1, and having an imide concentration of not less than 15% and not more than 36%, 

Insulated electric wire and coil using same

An insulated wire used under a condition where the insulated wire is brought into contact with ester-based synthetic oil includes a conductor and an insulating film on a periphery of the conductor. The insulating film is composed of an insulating paint including at least one resin component selected from polyamide imide, polyester imide, and polyimide and inorganic fine particles including alkali metal ion or alkaline-earth metal ion.

Insulated wire, and coil and motor formed using the insulated wire

An insulated wire includes a conductor, and an insulating covering layer including a first insulation layer formed around the conductor and a second insulation layer formed around the first insulation layer. An elastic modulus of the second insulation layer at 300&#xb0; C. is not less than 300 MPa, and a relative permittivity of the insulating covering layer is not more than 3.0.

Insulated wire and coil

There is provided an insulated wire including: a conductor wire; and a polyamide-imide insulation coating formed around the conductor wire, the polyamide-imide insulation coating being made from a polyamide-imide resin based insulating varnish, the varnish being synthesized by reaction of an isocyanate constituent and an acid constituent in a solvent, the isocyanate constituent including 5 to 50 mol % of 2,4'-diphenylmethane-diisocyanate having a flexible molecular structure.

Polyamide-imide resin based insulating varnish and insulated wire covered with same

A partial-discharge-resistant insulating varnish has a polyamide-imide enamel varnish and an organo-silica sol that are dispersed in a solvent. The solvent has 50 to 100% by weight of &#x3b3;-butyrolactone. An insulated wire has a conductor, and a partial-discharge-resistant insulation coating film formed on the surface of the conductor. The partial-discharge-resistant insulation coating film is made of the partial-discharge-resistant insulating varnish.

Method of making partial-discharge-resistant insulated wire

A insulated wire includes a conductor, and an insulating coating on a periphery of the conductor. The insulating coating includes an insulating film formed by applying and baking a polyester imide resin insulating coating material, and the insulating film has a relative permittivity of less than 3.5 both in a dried state and in a moisture-absorbed state. The insulating film is formed by applying and baking a polyester imide resin insulating coating material including an imide dicarboxylic acid and an alcohol component, the imide dicarboxylic acid being obtained by synthesizing a diamine component including aromatic diamine having not less than three aromatic rings and an acid component including aromatic tricarboxylic acid anhydride.

Polyester imide resin insulating coating material, insulated wire using same, and coil

An insulated wire includes a conductor, a partial-discharge-resistant layer formed on the conductor and including an insulating coating material including a base resin coating material and an inorganic fine particle dispersed in the base resin coating material, and an adhesion layer formed between the conductor and the partial-discharge-resistant layer and including an insulating coating material including the base resin coating material and an adhesion improver. A decrease rate in adhesion strength of the adhesion layer to the conductor after 20% elongation relative to that before the elongation is less than 25%.

Insulated wire

Partial-discharge-resistant insulating varnish, insulated wire and method of making the same

There is provided an insulated wire including a wire conductor and an insulation coating formed on the wire conductor by extrusion coating a resin composition. The resin composition is a mixture of a polyphenylene sulfide-based resin (A) and a polyamide-based resin (B), in which a ratio of parts by mass of the resin (B) to that of the resin (A), i.e. (B)/(A), is not less than 5/95 and not more than 30/70.

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Hitachi, Japan

Hideyuki Kikuchi