Paper tray container

Provided is a paper container that can be heated by a microwave oven and can be held by hand without causing a burn even if the content is heated. A method for producing a multilayer film, comprising: Forming, from at least a top surface, a barrier film layer (101) including a barrier layer, a paper substrate layer (102), a low-melting thermoplastic resin layer (103) containing a blowing agent, Wherein the paper substrate layer has a basis weight in the range of 80 to 400 grms per square meter and has breaking strength in the flow direction (MD direction) of 50 to 15 mm and heat in the width direction (TD direction) of 400 N/15 mm, and a melting point in the width direction (TD direction) of 50 to 400 N/15 mm; A thermoplastic polymer having a melting point of 130 degrees Scientific, a foaming agent having a diameter of 550...