Patent ID: 6130597
Filing Date: 2000-10-10
Classification: H01C,Y10T

Abstract:
A method of making an electrical device suitable for use in applications of less than 60 volts which comprises(A) a resistive element which (i) has a thickness of at most 0.51 mm, (ii) is crosslinked to the equivalent of 1 to 20 Mrads by irradiation, and (iii) is composed of a conductive polymer composition which comprises(1) a polymeric component having a crystallinity of at least 20% and a melting point T.sub.m, and(2) dispersed in the polymeric component a particulate conductive filler which consists essentially of carbon black; and(B) two electrodes which (i) are attached to the resistive element, (ii) comprise metal foils, and (iii) are suitable for connection to a source of electrical power,said method comprising the steps of(a) preparing a laminate comprising the conductive polymer composition positioned between two metal foils,(b) cutting a device from the laminate,(c) exposing the device to a thermal treatment at a temperature T.sub.t which is greater than T.sub.m,(d) cooling the device, and(e) crosslinking the device in a single irradiation step, said irradiation step being the only irradiation step,steps (a) to (e) being conducted in sequence.