Process for the production of padding of polyurethane foam cast in situ in a textile covering

Abstract

Cushions are produced from padding of polyurethane foam cast in situ in a textile covering. There are disposed successively in a mold (1) a textile (2) overlaid by a foam sheet (3) with cells that are open and communicating, and then a fluid-tight film (4), e.g. of glue. The composite (5) thus obtained, adapted to constitute the covering of the cushion, is held against the internal wall (6) of the mold (1) by suction, and then there is cast in the mold (1) a foaming mixture of polyurethane (7) which expands and hardens after closing of the mold (1). Finally, a microperforation of the fluid-tight film (4) is effected, thereby to confer on it good permeability to water vapor and permitting also to generate, by the effect of suction, an underpressure in the foam (8) in the course of hardening, such that the resulting padding of foam (8) will have, after polymerization and demolding, constituent cells (11) that are open and communicating. This microperforation is effected by heating the composite ( 5) to the softening point of the film of glue (4) and by aspiration under vacuum at the level of the internal wall (6) of the mold (1), giving rise to the penetration by suction of the softened film of glue (4) into the surface cells of the sheet of foam (3) and, as a result, the obtention of substantially point elongations of the film of glue (4) leading to microruptures in this latter and permitting also to produce a unification by thermobonding of the film of glue (4) with the sheet of foam (3).

Dependencies are inferred from the claim text.