| 摘要 |
1,196,090. Microporous laminates. UNIROYAL Inc. 19 April, 1968 [18 May, 1967], No. 18546/68. Heading B5N. [Also in Divisions B1-B2 and D1] A poromeric material comprises a sheet of normally solid, film-forming polymer in the form of nodules and fibroids of froth coalesced together at parts of contact, the nodules and fibroids containing internal bubbles. The material is obtained by dissolving gas in a solution of the polymer in an organic solvent and spraying the solution on a receiving surface and directing an air stream having a velocity higher than that of spray through the sprayed particles to atomize the particles before deposition on the receiving surface, the solution being maintained under pressure until the instant of spraying when it enters the zone of low pressure so that the gas comes out of solution to form bubbles in the sprayed particles of solution, which particles, when deposited on the receiving surface partially coalesce to form the microporous sheet. The film-forming polymer may be a thermoplastic polyurethane elastomer, a vinyl resin such as polyvinyl chloride which may be mixed with other polymers such as polyurethanes, butadiene-acrylonitrile copolymers, thermosetting polyurethanes or vulcanizable rubbers, or block copolymers of styrene and butadiene. Nitrocellulose may also be present. Numerous suitable solvents are specified and plasticizers may be also present as well as antioxidants, pigments and other suitable compound ingredients. The gas may be a nitrogen or carbon dioxide and the support may be a release paper which is provided with a pattern such as a negative reproduction of a leather-like grain to impart the grain of the leather to the product. A number of successive layers may be built upon the receiving surface by repeated spraying and spraying conditions may be varied so as to deposit first a relatively dense layer and then further a less dense layer. The products may be laminated to a fabric, such as a drill type fabric or to a rubber coated fleece, using a conventional rubber cement. |
