Abstract: An upright injection-compression pressing machine for the manufacture of information carrier discs, such as photograph records and video discs, has a mold clamper assembly including a pair of stamper bearing molds movable relative to each other in a vertical direction towards and away from each other, and an injector assembly mounted on the clamper assembly in alignment with the direction of the relative movement of the molds.

Abstract: A method of producing a plate-shaped body, particularly a video disc in which circumferential warp in the thicknesswise direction, thickness fluctuation and deflection of the signal track are minimized comprisingThe steps of pressing by a mold a thermoplastic resin which has been heated to a temperature above the softening point thereof, and cooling the thermoplastic resin to solidify the same. During the cooling, the pressure of the mold is decreased to a low level when the thermoplastic resin has been cooled down to a temperature around the softening point. The thermoplastic resin is allowed to be solidified without any substantial and local residual stress to ensure minimal circumferential warp, thickness fluctuation and deflection signal track.