| 摘要 |
1310460 Laminates PARKE DAVIS & CO 19 April 1971 [28 Jan 1970] 20421/71 Heading B5N [Also in Division A5] A surgical dressing for application to burns, comprises a layer of reticulated open cell foam material and a mutually secured co-extensive gas-permeable backing sheet which is impermeable to liquids and to bacteria. In use, the layer of foam is placed against the surface of the burn and liquid exudate and debris are absorbed into the foam, and retained thereby the liquid impermeable backing sheet. The layer of foam is thin enough, preferably about <SP>1</SP>/ 16 inch, to maintain all the liquid exudate and debris near to the surface of the wound so that in use it adheres to the skin. Reticulated polyurethane foam with a small cell size and about 97% void volume may be used for the foam layer. Polypropylene film or an elastomeric material such as natural or synthetic rubber with calculated pore size distribution of 10<SP>-5</SP> to 5 x 10<SP>-4</SP> mm. may be used for the backing sheet. The foamed layer and backing sheet are secured by means of an applied gas permeable adhesive layer or by thermoplastic fusion. A polypropylene backing sheet may be first laminated on to an adhesive-coated release liner and then drawn away from the liner and passed through opposed callender rolls with a matching web of polyurethane foam roll, whereby the foam is pressed against the exposed adhesive, and the resulting adhesively bound laminate wound on to a takeup roll. Alternatively individual sheets of backing and foam can be laminated together in separate sheets. |
