abstract |
An electric current regulating junction that can be electrically activated to a low resistance state in which it is capable of passing a relatively low reading current. The junction is capable of being activated electrically so as to be switched between low resistance and relatively high resistance states and vice versa. To switch from the low resistance to the high resistance state, one may apply relatively low currents (at least 10 times the magnitude of the reading current) in the form of a current-limited pulse, the pulse being regulated so that it will decay rapidly at the end. The junction comprises a normally insulative, electrically activatable composition having an electrical resistance greater than 10 8 ohms through a layer 0.1-2,540 microns thick. The composition consists essentially of 10 to 90 volume percent of a substantially linear, unitary polymeric binder, and 10 to 90 volume percent of particles substantially homogeneously dispersed in the binder having an electrically conductive metallic interior and a thin insulative surface coating sufficient to impart contact resistance. The unitary polymer has a glass transition temperature of at least 100° C. and may be an aromatic polyimide, poly(amide-imide), poly(ester-imide) or polyamide. |