To prevent a silicone rubber sheet from being broken in thermocompression bonding.

This cushioning material 10 is arranged in a space between a part where a liquid crystal display panel is joined with a driving unit and a thermocompression bonding tool 4 when subjecting the part where the liquid crystal display panel is joined with the driving unit to thermocompression bonding by using the thermocompression bonding jig 4, and the cushioning material 10 has a structure in which metallic wires 12 are, as reinforcing members, buried in both side parts with which the tool 4 comes in press-contact, of a silicone rubber sheet 11. Thus, the silicone rubber sheet 11 can be reinforced by the metallic wires 12, so that, even when the width of the silicone rubber sheet 11 is narrowly formed, and also, its thickness is thinly formed, the cutting of the silicone rubber sheet 11 can be prevented in thermocompression bonding.