Patent ID: 6579566
Filing Date: 2003-06-17
Classification: C08G,H02K

Abstract:
A process for preparing resin impregnated wire windings comprisinga) heating said wire windings in an oven to a temperature of about 110 to about 200Â° C.; b) subsequently trickling a one-component impregnating resin, which is storage-stable at room temperature, onto the heated, rotating wire winding or dipping the heated, rotating wire winding in a bath filled with said one-component impregnating resin, wherein the impregnating resin consists essentially of: (A) an epoxy resin that is liquid at room temperature; and (B) a heat-activatible initiator for the polymerisation of the epoxy resin, the initiator comprising (a) at least one quarternary ammonium salt of an aromatic-heterocyclic compound which contains 1 or 2 nitrogen atoms, and of a complex halide anion selected from the group consisting of BF4&thgr;, PF6&thgr;, SbF&thgr;6, SbF5(OH)&thgr; and AsF6&thgr;, and (b) at least one thermal radical former (b1), (b2), (b3) or (b4), wherein (b1) is a diarylethane derivative of formula III â€ƒwherein Ar is phenyl, naphthyl, or C1-C4alkyl- or chloro-substituted phenyl, R6 is hydroxy, C1-C4alkoxy, â€”Oâ€”Câ€”OR8 or â€”OSiR9R10R11, wherein R8 is C1-C8alkyl or phenyl, and R9, R10 and R11 are each independently of one another C1-C4alkyl or phenyl, and R7 is C1-C4alkyl or cyclohexyl or has the same meaning as Ar, (b2) is an oligomer of formula IV â€ƒwherein Ar, R7, R9 and R10 have the same meaning as in formula II and n is 2-20, (b3) is an organic peroxy compound, and (b4) is a quinone.