| 摘要 |
1330980 Reticulating polymeric foams TENNECO CHEMICALS Inc 24 Nov 1971 [1 Dec 1970 54618/71 Headings C3C and C3R Polymeric foams are reticulated by longitudinally moving a strip of the foam over first, second and third adjacent transverse zones, while supporting the foam strip on a hard and resilient porous surface, reducing the pressure beneath the first and third zones and directing a continuous jet of fluid against the surface of the foam strip as it passes over the second zone, the jet being substantially perpendicular to the tangent to the surface of the foam at the second zone and at a velocity and mass flow rate sufficient to rupture cell walls. The polymeric foam is preferably a polyurethane foam but also maybe a polyethylene, polypropylene, polyvinyl chloride, silicone, neoprene or rubber latex foam. The fluid used to rupture cell walls may be a liquid, e.g. water or a gas, especially air. Fig. 3 illustrates an apparatus which may be used. A first drive arrangement for the foam web is provided by driven, gear-connected pull rolls 40 and 41 and a second arrangement by roll 43 which is immediately upstream of windup roll 45. Two vacuum chambers 55 attached to an exhaust fan are located between rolls 41 and 43 and a moving steel-mesh screen 60 which passes round guide rolls 62, 63, 64 and 65 and is driven by roll 66 is supported on the upper surfaces 56 of the chambers 55. Take-up roll 68 maintains the tension of screen 60. The non- perpendicular sides 67 of the chambers 55 form a diverging nozzle. Fluid jets from the nozzle 70 and passes through the foam web and between the two chambers 55. The foam may be used as a fabric lining. |
