To provide an adhesive usable under the environment of high temperature, whose adhesive strength is proper to surely fix a low rigidity material to a supporter when the material is subjected to processing and to easily separate it after the processing without giving damage and deformation thereto, and, in addition, no adhesive sticks or remains onto the separated material.

The heat-resistant adhesive is composed mainly of a (meth) acrylic compound obtained by copolymerizing a monomer containing an acryloyl or methacryloyl group with a monomer containing a polar group and having an average molecular weight of 100,000-2,000,000, and a crossliking agent. The adhesive strength of its adhesive layer is 0.1-3.5 N/25 mm by JIS Z0237 after the treatment of heating for 6 hours at 180°C.