Metallackdraehte

Lacquered metal wires have electrically insulating lacquer coat(s), at least one of which consists of an organically modified silica (hetero)polycondensate (I). (I) is obtained by (partial) hydrolytic condensation of compound(s) of silicon (Si) and optionally other element(s) selected from boron (B), aluminium (Al), phosphorus (P), tin (Sn), lead (Pb) and transition, lanthanide and actinide metals and/or precondensates derived from these compounds. Condensation is carried out with water and moisture, optionally in the presence of a catalyst and/or solvent. Also claimed is a method of producing the lacquered wires. USE - The lacquered wires are used for making coils or windings e.g. in electric motors or clocks (all claimed). ADVANTAGE - Lacquers based on polyimides and polyamides cannot always withstand the mechanical stress occurring especially in coil winding. Satisfactory flexibility is required, together with Increased adhesion and resistance to scratching, scraping and abrasion, e ven at relatively high temperatures, and there should be no harmful emissions on heating. Other requirements are fast cure and the use of no or non-toxic, non-corrosive solvent. The present lacquer cures rapidly, whilst its mechanical, thermal and electrical properties are better than usual. The required properties can be optimised for all or special applications.