Insulating tape and production method thereof, stator coil and production method thereof, and rotating electric machine

A method for producing an insulating tape, comprising:

• forming a mica layer through sheet-forming of a dispersion containing mica;
• forming a reinforcing layer by bonding a fiber reinforcing material to the mica layer and then coating the fiber reinforcing material with a slurry that contains a filler having a maximum particle size of 100 μm or smaller;
• and
• forming a cellulose derivative layer by coating the reinforcing layer with a slurry that contains a cellulose derivative in which one or more hydroxyl groups in the glucose units are substituted with at least one functional group selected from the group consisting of —CH2CH2OH, —CH2CH2OCH2CH2OH, —CH2CH(OH)CH3, —CH3, —CH2CH3, —NO2, —(CH2CH2O)pH, in the formula, p is any repeating number greater than 0 up to 50, —CH2COOH, —CH2CH2COOH, —CH2COOM, in the formula M is Li, Na or K, and —(CH2CH2O)qCH2CH(OH)CH2N+(CH3)2(n-C12H25)X−, in the formula, q is any repeating number from 0 to 50, and X− is Cl−, Br−, F− or I−,
• wherein the weight per unit area of the mica is set to a range from 100 g/m2 to 200 g/m2,
• the weight per unit area of the filler is set to a range from 10 g/m2 to 50 g/m2, and
• the weight per unit area of the cellulose derivative layer is set to a range from 0.001 g/m2 to 5 g/m2.