Arc-quenching compositions for high voltage current limiting fuses and circuit interrupters

Abstract

Arc-quenching coating compositions are provided with effective arc-extinguishing properties and improved track resistance properties, and are relatively easy to apply in liquid form. The coating compositions are used, for example, in high voltage current limiting fuses, expulsion fuses, circuit breakers, circuit interrupters, separable cable connectors, or the like for interrupting circuits. The arc-quenching coating compositions include an arc-quenching gas-evolving material (A) and a film-forming polymer (B) having minimal tracking properties, in which the film-forming polymer (B) acts as a liquid vehicle for the coating composition. The arc-quenching material (A) is preferably selected from the group of guanidine, guanidine carbonate, guanidine acetate, 1,3-diphenylguanidine, guanine, melamine, melamine cyanurate, urea, hydantoin, allantoin and derivatives and mixtures thereof. The film-forming polymer (B) is preferably selected from the group of urethane, acrylic, melamine-formaldehyde polymers and derivatives and mixtures thereof. Arc-quenching compositions are also provided with effective arc-extinguishing properties, improved non-tracking properties, and thermal stability, and the compositions are selected from the group of gas-evolving materials (A) of guanidine carbonate, guanidine acetate, 1,3-diphenylguanidine, guanine, melamine cyanurate, urea, hydantoin and allantoin.

Dependencies are inferred from the claim text.