PURPOSE: To provide a container capable of withstanding the simple sterilization of food by constituting a heat-resistant polyester sheet having a two- or three- layered structure consisting of a main layer and a sub-layer and using a polycarbonate resin having heat resistance in the sub-layer and specifying the ratio thereof to the total thickness of the sub-layer.
CONSTITUTION: A heat-resistant polyester sheet is composed of a two-layered structure of a polyester layer and a polycarbonate layer and characterized by that the thickness of the polycarbonate layer is 20-90% of the total thickness of the polyester sheet. A sheet producing apparatus to be used consists of a coextrusion device consisting of a main extruder 6, a sub-extruder 5 and a coextrusion T-die 7 and a taking-up device having function adjusting the thickness of an extruded sheet and forming the sheet into a roll shape. The polyester resin becoming a main layer 1 is charged in the main extruder 6 and the polycarbonate resin becoming a sub-layer 2 is charged in the sub-extruder 5 and a two-layered structure is extruded from the coextrusion T-die connected to both extruders.
WATABE TOSHIAKI
SATA NAGAYUKI
TAN NOBUO
NAGASE & CO LTD