The test piece must be made by the same foaming conditions as mass production, and there must not be a crack, mixing of garbage and a big dent in the test piece. Hereafter, it tests by using three kinds of molded test pieces of 250±10N,300±10N at ∮200 in hardness. The measuring method and molded test piece of hardness is referred to 3.3. Various test pieces cutting out procedures are shown from the molding test piece in the figure below.