Patent Application
20070066921
This invention is aimed at providing a cushioning pad such as used on a seat or a bed having a thin water-repellent skin bonded directly onto a surface of the pad without any intervening adhesive layer and a method for producing an article of this nature. More specifically, the invention is directed toward a product of the nature described in which the cushioning pad is an open cell foam cushioning material.
There are a number of commercially available seat cushions or the like which have a padding of open cell foam such as polyurethane foam enclosed in or covered by a relatively thin layer of water-repellent material where the covering is not bonded directly onto the surface of the foam padding. Also there are foam pads or cushions having a water-repellent skin which is attached to the pad by an intervening layer of adhesive.
There is also an open-cell polyurethane pad with a bonded skin which is produced by first spraying the interior of the shell of a mold with a resin and then inserting a polyurethane cushioning material into the mold and then closing the mold shell and applying suitable pressure and temperature so that the thin layer of resin adheres directly onto the surface of the foam material when the mold is opened. This process for making the molded product as described hereinabove is a process used by or originated by BASF Corporation located in Wyandotte, Mich. and is described and shown in a CD which is available from that company.
A water-repellent skin is formed on a suitably dimensioned pad of open cell polyurethane foam cushioning material by spraying it at room temperature with a two-component spray-in-place flexible 100% solids elastomer polyurea system. The two components are a resin and isocyanate and the combination is applied through plural component high pressure impingement mix polyurethane dispensing equipment. The two components which are sprayed on the cushioning pad are the same as the components which are sprayed on the interior of the shell as described hereinabove in the process of using a mold for producing the product. Since, according to the instant invention, the skin-forming components are sprayed directly onto the pad of cushioning material in situ and at room temperature to produce the water-repellent bonded skin, the benefit of the savings in time and labor alone is apparent. Also, the method can be used for almost any size or shape of cushion.
The details of the materials used to produce the water-repellent skin on the polyurethane foam cushioning material and the equipment used in the process and the specifications as to any properties of the component materials and the various equipment settings as necessary to produce the end product, to the extent that they are publicly disclosed, are available from BASF Corporation of Wyandotte, Mich. Applicant makes no claim to inventorship of the component materials or equipment or equipment settings, etc. used in this process for forming the skin on the cushioning material. Nor does applicant make any claim of inventorship or originality with respect to the cushioning material itself. For the purposes of this application for patent, applicant presumes that the component materials, the equipment, the equipment settings, etc. are not unique and are publicly known or available so do not require any detailed description.
For producing a skin bonded directly onto the surface of the open cell polyurethane foam, as described in a product data sheet of BASF Corporation a two-component spray-in-place system is used. The two components are a resin and isocyanate which are fed separately into a high-pressure spray-in-place plural component dispensing equipment. In the instant invention the resulting combination of the two components is sprayed at room temperature directly onto a surface of a cushion or pad of polyurethane open cell foam in situ to produce a fast cure smooth surface which is water-repellent after curing and adheres or bonds firmly directly to the surface of the polyurethane foam without the need for any intervening adhesive layer.
As illustrated diagrammatically in
After the two-component material has been sprayed onto the surface of the cushioning pad 14 and suitable curing time has passed, as illustrated in cross-section,
In some cases it is not necessary to coat all the surfaces of the cushioning pad 14. For example, a boat seat pad usually rests on a supporting plate so the underside of the pad may not have to be covered with the coating skin. As illustrated in
According to the specification sheet the water-repellent coating formed in the manner described may not be light-fast and so over a period of time it might deteriorate when exposed to light and lose its water-repellent characteristic. For this purpose and for cosmetic reasons, the coated pad is usually covered with some type of cosmetically-pleasing vinyl or other suitable covering.
A significant benefit achieved by this invention is that a variety of shapes and sizes of blocks of cushioning material having a variety of contours for a variety of styles of seats or the like can be made with a water-repellent skin without the need of different molds for each style, shape or size.
