Mitsubishi Electric Corporation

Shiori Natori

Naoki Yasuda

Kazuya Hasegawa

Shogo Okamoto

Kenji Maekawa

Yasuhiro Hayasaka

In the insulation sheet, an insulation resin layer made of a thermosetting resin composition in an uncured or semi-cured state is formed on one or each of both surfaces of the base material. The thermosetting resin composition contains: a thermosetting resin (A) that is in solid form at 25° C.; a thermosetting resin (B) that is in liquid form at 25° C.; a latent curing agent that is unreactive at 60° C. or lower; and an inorganic filler having a maximum particle diameter smaller than a film thickness of the insulation resin layer and having an average particle diameter smaller than 0.5 times the film thickness. The insulation resin layer of the insulation sheet is efficiently compressed into a predetermined thickness by pressure application at normal temperature and permeates a gap between a stator core and a stator coil by heating during curing treatment, whereby both members can be insulated and fixed.

Insulation sheet and producing method therefor, and rotary electric machine

The thermosetting resin composition is used for a sheet-form insulating varnish to be disposed in a gap between insulation target members, and contains: a thermosetting resin (A) that is in solid form at 25° C.; a thermosetting resin (B) that is in liquid form at 25° C.; a latent curing agent that is unreactive at 60° C. or lower; and an inorganic filler having a maximum particle diameter smaller than a dimension of the gap and having an average particle diameter smaller than 0.5 times the dimension of the gap. 30 parts by mass to 70 parts by mass of the thermosetting resin (A) is contained per a total of 100 parts by mass of the thermosetting resin (A) and the thermosetting resin (B). A volume ratio of the inorganic filler to an entirety of the composition is not higher than 50%.

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Tokyo, Japan

Shiori Natori