Abstract:
A manufacturing method uses a solid coating die for applying an insulation varnish around a flat wire conductor. The die includes a die body and a die hole formed through the die body, into which the conductor is inserted. The die hole includes an entry portion having a cross section monotonically decreasing along a conductor insertion direction, and a coating portion including at least a sub-portion having a constant cross section. The cross section of the coating portion is a rectangle having four straight sides and four rounded corners. Each inner surface of each straight side has an inwardly projecting protrusion, a top contour of each protrusion being a circular arc, an elongated circular arc, an elliptical arc or a combination of these arcs, the maximum curvature of the top contour of each protrusion being larger than the maximum curvature of inner surface of the rounded corners.
Abstract:
A polyamide-imide resin insulating paint according to the present invention includes polyamide-imide resin containing no halogen element in its molecular chain which is dissolved in a polar solvent, in which the polyamide-imide resin contains an aromatic diisocyanate component (A) having three or more benzene rings or an aromatic diamine component (E) having three or more benzene rings in a monomer, and a ratio M/N between a molecular weight (M) of the polyamide-imide resin per repeat unit and an average number (N) of amide groups and imide groups is equal to or more than 200.
Abstract:
A polyamide-imide resin insulating paint according to the present invention includes polyamide-imide resin containing no halogen element in its molecular chain which is dissolved in a polar solvent, in which the polyamide-imide resin contains an aromatic diisocyanate component (A) having three or more benzene rings or an aromatic diamine component (E) having three or more benzene rings in a monomer, and a ratio M/N between a molecular weight (M) of the polyamide-imide resin per repeat unit and an average number (N) of amide groups and imide groups is equal to or more than 200.