PTC composition, method of making the same, and thermistor body obtained therefrom

摘要

In a first aspect of the present invention, a PTC composition contains (a) a crosslinked polymer matrix having a gel fraction of at least 10%, and (b) an electrically conductive substance. An article shaped therefrom yields an electric resistance of at least 50 mOmega at 25° C. after being placed in an environment repeating 200 times of a temperature change between -40° C. and +85° C., and exhibits no thermal deformation when placed on a hot plate at 200° C. for 5 minutes.