Method for producing bookcovers

摘要

A method of producing book covers, which method includes cutting at least one elongated notch along the length of one side of a sheet of comparatively rigid plastics having a "memory" (as herein defined) and stretching the plastics defining the floor of the notch to alter its molecular structure so as to provide a readily foldable hinge, said stretching being effected by pressing the plastics defining the floor of the notch outwardly from the notch to raise a ridge on the other side of said sheet.