Method for producing foamed articles

Abstract

Disclosed herein is a method for producing foamed articles, such as seat cushions for a riding lawn mower or the like, which method includes the steps of providing a mold having at least two separable, electrically insulated mold sections, which, when positioned together in a molding position, cooperate to define a molding chamber having the shape of the article, providing each mold section with a separate radio frequency electrode, introducing a foamable and heat curable material into the mold cavity, and applying a radio frequency voltage across the electrodes, and thus through the foamable and heat curable material, after the mold sections are positioned together in a molding position. The resultant internal heating of the material rapidly cures the material to a hardened condition and without generating high internal pressure forces inside the molding chamber. In one embodiment, a skin-forming material, such as a sheet or film of a flexible thermoplastic resin, is laid over the mold cavity of one of the mold sections and is vacuum formed into conformity with the contour of the molding section surface and a foamable and heat curable pad-forming material is introduced into the molding chamber on top of the skin-forming material prior to the application of the radio frequency voltage.