SEPARATOR HAVING HEAT-RESISTANT INSULATING LAYER

A separator having a heat-resistant insulating layer of the present invention includes a porous resin base layer and a heat-resistant insulating layer which is formed on one or both sides of the porous resin base layer and contains inorganic particles and a binder. The porous resin base layer contains a resin having a melting temperature of 120°C to 200°C. The separator is configured so that the ratio of the basis weight of the heat-resistant insulating layer to the basis weight of the porous resin base layer is not less than 0.5. Accordingly, the separator having a heat-resistant insulating layer of the present invention exhibits excellent thermal shrinkage resistance while ensuring a shutdown function.