A polymer positive temperature coefficient (PPTC) material may include a polymer matrix, the polymer matrix defining a PPTC body; and a graphene filler component, disposed in the polymer matrix, wherein the graphene filler component comprises a plurality of graphene particles aligned along a predetermined plane of the PPTC body.

Provided are a thermistor element including a conductive intermediate layer containing RuO.sub.2 which can have a lower resistance and a thinner profile, whereby the increase in resistance can be suppressed even when peeling of the electrode proceeds; and a method for producing the same. The thermistor element according to the present invention includes: a thermistor body 2 made of a thermistor material; a conductive intermediate layer 4 formed on the thermistor body; and an electrode layer 5 formed on the conductive intermediate layer, wherein the conductive intermediate layer has an aggregation structure of RuO.sub.2 particles that are in electrical contact with each other where SiO.sub.2 is placed in the gaps in the aggregation structure, and has a thickness of 100 to 1000 nm.

Provided are a thermistor element including a conductive intermediate layer containing RuO.sub.2 which can have a lower resistance and a thinner profile, whereby the increase in resistance can be suppressed even when peeling of the electrode proceeds; and a method for producing the same. The thermistor element according to the present invention includes: a thermistor body 2 made of a thermistor material; a conductive intermediate layer 4 formed on the thermistor body; and an electrode layer 5 formed on the conductive intermediate layer, wherein the conductive intermediate layer has an aggregation structure of RuO.sub.2 particles that are in electrical contact with each other where SiO.sub.2 is placed in the gaps in the aggregation structure, and has a thickness of 100 to 1000 nm.

A negative temperature coefficient type thermistor that comprises at least two conductor terminals and a thermistor structure formed of particles of lithium manganese oxide in a spinel structure within a polymer binder. The thermistor is configured to operate in a temperature range below a predefined first temperature and the polymer binder is selected so that its heat distortion temperature is higher than the first temperature. The manufacturing process further includes a stage of calendaring the thermistor structure in a temperature that is higher than the heat distortion temperature of the polymer binder.