Abstract: The present invention provides an electronic component separator that allows for easy thickness reduction and also has excellent mechanical strength, dimensional stability and heat resistance. This electronic component separator contains in a porous film made of a synthetic resin with a glass transition temperature of 180° C. or above, filler grains having a melting point of 180° C. or above or virtually no melting point, and the electronic component separator is produced by way of applying onto a base a coating material comprising (a) a synthetic resin with a glass transition temperature of 180° C. or above, (b) filler grains having a melting point of 180° C. or above or virtually no melting point, (c) at least one good solvent capable of dissolving the synthetic resin, and (d) at least one poor solvent incapable of dissolving the synthetic resin, and then drying the coated base to form a porous film.

Abstract: The reversible heat-sensitive recording medium having a heat-sensitive recording layer capable of reversibly changing the transparency thereof with organic low molecular substances dispersed in an organic macromolecular resin provided on a support is characterized by using at least one long chain alkyl-containing compound having a melting point of 50.degree.-100.degree. C. and at least one saturated aliphatic bisamide having a melting point of not less than 110.degree. C. as the organic low molecular substance in a ratio of 98:2 to 80:20. A plasticizer may be contained in the organic macromolecular resin in a ratio of 1 to 10% by weight, based on the total solid of the heat-sensitive recording layer.