PURPOSE: To provide the titled varnish which has good wettability and adhesion to self-lubricating wires and gives a treated coil which suffers neither creeping leak breakage nor beating caused by electromagnetic vibration, by incorporating a specified silicone compd. in paints.

CONSTITUTION: The titled varnish is obtd. by incorporating 0.05W3.0pts.wt. compd. contg. alkylene ether and siloxane linkages in the molecular backbone and having an MW of pref. 500W50,000 [e.g. a compd. of the formula (wherein m≥1; n≥1; A≥1; X is H, CH3, OH; Y is H, COCH3; R is H, CH3, C6H5)] in 100pts.wt. (on a solid basis) paint. A self-lubricating wire is molded into a coil, which is then impregnated with the varnish and heated to obtain a treated coil. The varnish has good wettability and gives a treated coil which suffers neither creeping leak breakage nor beating caused by electromagnetic vibration.