Abstract: A method for tuning a resistance v. temperature profile of a surface mountable polymeric PTC device for use as an overtemperature protection device. The method includes preparing a laminate comprising a conductive polymer composite sandwiched between metal foil electrodes; crosslinking the laminate; forming a panel from the crosslinked laminate by patterning the laminate to form a plurality of surface mountable devices; irradiating the panel using electron beam irradiation of at least 20 Mrad; and providing individual devices by subdividing the irradiated panel.

Abstract: An electrical device which includes a resistive element which exhibits PTC behavior, is composed of a conductive polymer composition, has a planar shape with first and second major surfaces, and has a thickness of at most 0.64 mm . The resistive element is sandwiched between first and second metal foil electrodes, at least one of which has a thickness of at least 0.055 mm, so that the ratio of the resistive element thickness to electrode thickness is 1:1 to 16:1. The device can be used as a circuit protection device in an electrical circuit.

Abstract: A conductive polymer composition which has a resistivity of less than 10 ohm-cm and which exhibits PTC behavior comprises a polymeric component and a particulate conductive filler. The polymeric component comprises a first crystalline fluorinated polymer having a first melting point T.sub.m1 and a second crystalline fluorinated polymer having a second melting point T.sub.m2 which is from (T.sub.m1 +25).degree. C. to (T.sub.m1 +100).degree. C. The composition exhibits one of a number of characteristics, including a relatively high PTC anomaly. The composition is useful in circuit protection devices to be used at high ambient conditions.