| abstract |
The insulated wire having excellent thermal resistance and good surface appearance is obtained by producing from specific polyimide represented by formula I in a temperature range of 300 °C to 450 °C and controlling moisture content to 200ppm or less in the polyimide used as raw materials.n wherein R is a tetravalent radical selected from the group consisting of an aliphatic radical having two or more carbon atoms, a cyclo-aliphatic radical, a monoaromatic radical, a condensed polyaromatic radical and a non-condensed polyaromatic radical wherein the aromatic radicals are mutually connected with a bond or a crosslinking function, X is a divalent radical of a single bond, sulfur atom, sulfonyl radical, carbonyl radical, isopropylidene radical or hexafluoroisopropylidene radical. |