	US 12,291,616 B2
	Insulating varnish composition, rotating machine coil and rotating machine
Takahiro Mabuchi, Tokyo (JP); and Xiaohong Yin, Tokyo (JP)
Assigned to MITSUBISHI ELECTRIC CORPORATION, Tokyo (JP)
Appl. No. 17/616,201
Filed by Mitsubishi Electric Corporation, Tokyo (JP)
PCT Filed Jul. 16, 2019, PCT No. PCT/JP2019/027914 § 371(c)(1), (2) Date Dec. 3, 2021, PCT Pub. No. WO2021/009842, PCT Pub. Date Jan. 21, 2021.
Prior Publication US 2022/0243020 A1, Aug. 4, 2022
Int. Cl. C09D 7/40 (2018.01); C08J 5/24 (2006.01); C09D 163/00 (2006.01); H02K 3/30 (2006.01)

CPC C08J 5/241 (2021.05) [C09D 7/68 (2018.01); C09D 163/00 (2013.01); H02K 3/30 (2013.01); C08J 2363/02 (2013.01)]

20 Claims

1. An insulating varnish composition, comprising:

two or more epoxy resins having different skeletons or different numbers of repetitions in a molecular structural formulae; and

a filler having an average primary particle diameter of 500 nm or less,

wherein the two or more epoxy resins contain 80 mass % or more of an epoxy resin having a number of repetitions of 0 in a molecular structural formula thereof with respect to a total mass of the two or more epoxy resins,

wherein the two or more epoxy resins contain an epoxy resin having a bisphenol A skeleton, an epoxy resin having a bisphenol F skeleton, and an epoxy resin having a tetramethylbiphenol skeleton.