Toray's insulation varnish is an aromatic polymed precursor that forms a thin polyimide film, and is used to produce insulated enamel electrical wires and magnetic wires. The advantages are:

• Heat-resistance up to 392F (200C) continuously and up to 752F (400C) for brief periods.
• Low usage temperature at -516Ｆ (-269C).
• Superior wear-resistance.
• Chemical-resistance (except strong bases and methylene chloride).
• Versatility in shape and thickness.
• Ability for various fillers to be added.