Method of manufacturing a PTP sheet for packaging a pharmaceutical drug

A method of manufacturing a PTP sheet for packaging a pharmaceutical drug, comprising:

• positioning a first flat sheet of fixed thickness between a die and a heating plug, the die having a concavity, the heating plug having an annular-shaped end surface;
• contacting a partial region of the first flat sheet with the annular-shaped end surface, the annular-shaped end surface of the heating plug imparting heat to a corresponding annular shape at the partial region;
• decompressing a concavity of the die by flowing air from the concavity;
• in response to the decompressing sucking a pocket portion of the first flat sheet into the concavity and molding the pocket portion to a shape of the concavity, and
• extending length of the heated partial region during said decompressing and sucking, so that wall thickness of the partial region decreases relative to wall thickness of a remaining portion of the pocket portion and a portion of the first sheet surrounding the pocket portion;
• wherein the PTP sheet comprises the first flat sheet and a second sheet, the first flat sheet having a surface for facing the second sheet, the first flat sheet having a first portion, a second portion, and a third portion, the first portion and second portion configured for contacting the second sheet;
• wherein the third portion is configured during said sucking and extending steps as the pocket portion having sidewalls and a base portion, the pocket portion configured for holding the pharmaceutical drug;
• and
• wherein the partial region forms at least a portion of the sidewalls, the sidewalls having a wall thickness less than the wall thickness of the base portion, the first portion, and the second portion.