| abstract |
An insulating varnish capable of stably producing an insulated wire having an insulating film having an appropriate porosity as a porous insulating film is provided. An insulating varnish for forming a porous insulating film of an insulated wire, comprising a mother liquor containing a solvent, an insulating resin dissolved in the solvent or a precursor thereof, and dispersed in the mother liquor. An insulating varnish having a settling rate ν m per 30 days of −1.0 to 1.0 (cm / 30 days) of the thermally decomposable resin particles in the mother liquor. Preferably, the true density of the thermally decomposable resin particles is 0.85 to 1.40 g / cm 3 , and the concentration of the thermally decomposable resin or its precursor in the mother liquor is 10 to 50% by mass or less. Insulated varnish. [Selection] Figure 1 |