THERMOSETTING HEAT BONDABLE LACQUER

摘要

The thermosetting heat bendable lacquer comprises a solution of a thermosetting mixture of various resins in a solvent or mixture of solvents which boils at a temperature in the range of 50 to 230.degree.C, preferably 130 to 210.degree.C. The thermosetting mixture consists of a polyhydantoin resin, a polyhydroxy polyether or phenoxy resin and a polyurethane resin, each of which must have a pre-determined structure and a pre-determined specific viscosity. The composition of the thermosetting mixture must be within the hatched area in Fig. 1. The thermosetting heat bondable lacquer can be obtained by mixing solutions of the three resin components and can contain auxiliaries and additives and/or catalysts. If the solvent or mixture of solvents is removed from the heat bondable lacquer, e.g. by drying a thin coating produced therefrom or by precipitation with a non-solvent for the resin components, a mixture which is viscoelastic at room temperature and homogeneous is left, which mixture can be first molten and then cured by supplying heat. The heat bondable lacquer can be used in the production of baking lacquer wires, which serve for the manufacture of electromagnetic coils which can be subjected to high mechanical and thermal stresses, but it can also be applied to other carriers or be converted into heat bondable adhesive powders by precipitation in a non-solvent.