Patent attributes
A heat resistant release sheet of the present disclosure includes a polyimide substrate, and a first polytetrafluoroethylene (PTFE) layer and a second PTFE layer that sandwich the polyimide substrate therebetween. PTFE composing the first PTFE layer and PTFE composing the second PTFE layer each have a number-average molecular weight of 6 million or more, and a peel force required to peel the first PTFE layer from the polyimide substrate is 0.5 N/20 mm or more, and a peel force required to peel the second PTFE layer from the polyimide substrate is less than 0.5 N/20 mm. The heat resistant release sheet of the present disclosure has a new structure and can also be used for thermocompression bonding at a higher temperature.