Keytop for push-button switches, and method of manufacturing same

Abstract

A push-button switch keytop includes a flexible resin film deformed in such a manner that the resin film bulges upwardly to form a curved portion that is filled with a molding resin while the resin film is being deformed. The molding resin is allowed to harden to form a keytop body, whereby the top side of the keytop body consisting of the molding resin is integrated with the resin film in a state in which the top side of the keytop body is covered by the resin film. The keytop is manufactured by clamping a resin film between upper and lower molds, charging a molten resin from a pin gate provided on the lower mold into a cavity provided in the lower mold, thereby deforming and urging the resin film upward by pressure and heat produced by the molten resin and causing the resin film to adhere to the inner surface of the upper mold, filling the cavities of the upper and lower molds with the molten resin and separating the upper and lower molds after the resin hardens. An adhesive layer may be provided directly or indirectly via another printed layer on the underside of the resin film on that portion thereof where the keytop is located.