Process for producing fabric-backed cushioning material

Claim 1

A process for producing a cushion for seating, said process comprising: introducing a liquid reaction mixture into a mold cavity having an upwardly presented open end, the liquid reaction mixture being capable of expanding into a cellular material that has a high degree of flexibility so as to have good cushioning properties, the liquid reaction mixture being in sufficient quantity to substantially fill the entire cavity when expanded; attaching a thin composite backing to a rigid cover that is large enough to completely cover the open end of the cavity, the composite backing including a fabric and thin preformed layer of polyurethane cellular material with the fabric and the preformed cellular material being directly against each other and bonded firmly together such that the fabric extends substantially entirely over one major surface area of the preformed layer of cellular material, the preformed cellular material having open cells and being presented away from the cover so that the fabric is against the cover, the composite backing being attached to the cover at a plurality of locations, some of which are located near the margins of the backing and others of which are spaced substantially inwardly from the margins, so that the backing may be suspended from the cover without sagging away from the cover; placing the cover and the composite backing attached to it over the open top of the cavity such that another major surface area of the preformed cellular material is presented downwardly and exposed to the interior of the cavity, and such that a portion of the backing projects laterally beyond the upper margin of the cavity in the formation of a lip; allowing the reaction mixture to expand within the cavity into a molded cellular material which is sufficiently flexible to have good cushioning properties, with the expansion being sufficient to enable the molded cellular material to come against and partially penetrate the portion of the preformed layer of cellular material that overlies the cavity, but not to penetrate the lip or to reach the fabric, whereby the molded cellular material attaches to the preformed layer of cellular material while the fabric remains completely free of the molded cellular material so as to form a low friction surface across the back of the cushion; and venting the cavity through the open cells of the preformed cellular material as the reaction mixture expands in the cavity.