PROCESS FOR IMPREGNATING ELECTRICAL COILS AND EPOXY RESIN COMPOSITIONS FOR CARRYING OUT THE IMPREGNATION

摘要

- A thermosetting epoxide resin composition, which is solid at room temperature, contains (a) an epoxide resin, which is solid at room temperature, selected from (a1) polyglycidyl ethers based on novolaks and/or (a2) diglycidyl ethers based on bisphenol; (b) a hardener; (c) an accelerator; (d) 15-70 wt.% filler, selected from (d1) calcium carbonate (CaCO3), (d2) quartz powder and/or (d3) wollastonite particles with an average length/diameter ratio < 5:1, optionally mixed with other inorganic fillers; and (e) 10-60 wt.% acicular or fibrous inorganic reinforcement particles with a length of > 0.15 to 2.5 mm and average length/diameter ratio ≥ 5:1, the total amount being (d) and (e) NOTGREATER 80 wt.%. Also claimed is a method in which this composition or a variant is used for impregnating an electrical coil wound with several layers of more than one winding of plastics-insulated wire, with insulation between the individual windings.