Arc resistant molded members

Claim 1

IN A CIRCUIT INTERRUPTER DEVICE HAVING AN ELECTRIC CURRENT CARRYING MEMBER WHICH DEVELOPS AN ARC DURING CIRCUIT INTERRUPTING OPERATION OF THE DEVICE AND A MOLDED ELECTRICALLY INSULATING MEMBER DISPOSED ADJACENT TO THE ELECTRIC CURRENT CARRYING MEMBER AND IN CLOSE PROXIMITY TO THE POINT WHERE THE ARC DEVELOPS WHEREBY THE SURFACE OF THE MOLDED INSULATING MEMBER IS HEATED AND DECOMPOSED, THE IMPROVEMENT WHICH COMPRISES FORMING AT LEAST A SUBSTANTIAL THICKNESS OF THE SURFACE OF THE MOLDED ELECTRICALLY INSULATING MEMBER OF A THERMOSETTABLE MOLDING COMPOSITION CONSISTING OF (A) A RESIN DERIVED BY HEATING FROM 0.5 TO 0.86 MOLS OF AN ALDEHYDE WITH EACH ONE MOL OF DICYANDIAMIDE TO PROVIDE A THERMOPLASTIC RESIN, (B) A COMPOUND SELECTED FROM THE GROUP CONSISTING OF FORMALDEHYDE, PARAFORMALDEHYDE, FURFURALDEHYDE, ACETALDEHYDE, AND HEXAMETHYLENE TETRAMINE IN AN AMOUNT SUFFICIENT TO RAISE THE MOLAR RATIO OF DICYANDIAMIDE TO ALDEHYDE IN THE THERMOPLASTIC RESIN TO A RATIO OF AT LEAST 1:1, (C) A FILLER SELECTED FROM THE GROUP CONSISTING OF FINELY DIVIDED FIBROUS FILLERS AND INORGANIC REFRACTORY FILLERS, FROM 3% TO 70% BY WEIGHT OF SAID COMPOSITION BEING COMPOSED OF FINELY DIVIDED NON-CONDUCTING INORGANIC REFRACTORY PARTICLES HAVING AN AVERAGE PARTICLE SIZE OF NOT IN EXCESS OF 5 MICRONS.