PURPOSE:A laboratoy dish (petri dish), prepared by thermoforming a multilayer material of polypropylene, polycarbonate, etc. as a body and a polyethylene layer as the inner surface by the coextrusion method, and usable by stripping the polyethylene in the germfree state in use. CONSTITUTION:A multilayer sheet obtained by coextruding polypropylene, polycarbonate, polyethylene terephthalate or polystyrene with low- or high-density polyethylene is thermoformed by pressure forming or vacuum forming to give a container and a lid of a desired laboratory dish (petri dish). The extrusion is carried out up to a temperature of 200-300 deg.C under germfree conditions. Therefore, the polyethylene is stripped and removed by hand readily in use and usable in a germfree state without requiring boiling or other sterilizing methods. The polyethylene may be laminated on the outer surfaces of the container and the lid.
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