abstract |
Products in the form of cushioning devices made from flexible membranes employing at least one layer including thermoplastic urethane and at least one layer of a copolymer of ethylene and vinyl alcohol are inflatable to a relatively high pressure. The cushioning devices maintain the internal inflatant pressure for extended periods of time by employing a phenomenon referred to in the industry as diffusion pumping. Ideally, the cushioning devices of the present invention can be permanently inflated with gases such as nitrogen or air. |