| 摘要 |
<p>1325026 Poromeric; film laminated products GENERAL TIRE & RUBBER CO 3 Dec 1970 [11 Dec 1969] 57447/70 Headings B5B and B5N [Also in Divisions B2 and C3] A process of making a poromeric sheet material with a patent leather type finish comprises the steps of (a) casting a layer of a phaseinvertable polymer solution, comprising a chain extended urethane polymer, a polyvinyl chloride resin and a water miscible solvent on to a releasable substrate; (b) introducing superheated or saturated steam into the environment of the cast layer so as to give a layer surface temperature of between 120 and 210‹F. to phase in said solution and to produce a poromeric sheet material with a patent leather-type finish on the side of the material adjacent to the releasable substrate; (c) drying the poromeric sheet material and (d) removing the poromeric sheet material from the substrate. The sheet material may be subsequently soaked in a liquid comprising a major amount of water together with for example methanol and acetone to increase removal of water miscible solvent from the material. After either the step of casting or drying the sheet material an optional embodiment includes the step of adhering a layer of fabric or foam to the exposed surface of the material to form a laminate. The layer may be cast by blade coating or extruding the layer and the viscosity of the solution should be 10,000 to 75,000 cps and preferably 20,000 to 30,000 cps. Examples of releasable substrates are chromeferrous plates, polished steel surfaces, glass plates and polytetrefluoroethylene surfaces. In a further embodiment a thin layer of a solution of a hard wearing polymer is cast on to the releasable substrate, dried (not phase inverted) and then proceeding as previously described with the steam atmosphere phase-inverting the second layer. The reinforced sheet material may also be laminated as described above.</p> |
