Landau theory of relativitic fermi liquids

1,060,434. Tubular films. REINFENH€USER G.m.b.H. Feb. 7, 1964 [Feb. 11, 1963], No. 32611/66. Divided out of 1,060,433. Heading B5B. Apparatus for cooling continuous extruded air-inflated tubular films of thermoplastic resinous material comprises a liquid-cooled calibrating and supporting tube member attached to the extrusion nozzle and cooling the inflated film passing therethrough by direct contact, the tube member being provided, at the end remote from the extrusion nozzle, with an annular trough filled with a cooling liquid which is directed at the film through a plurality of nozzles distributed evenly around the circumference of the trough. The calibrating tube member may be of any desired crosssection and may taper in the direction of extrusion in accordance with the contraction of the cooling film. In one embodiment (Fig. 1, not shown) a tubular film 2 extruded from annular nozzle 1 is inflated and expanded to contact a calibrating tube member 3 which is connected to nozzle 1 and is cooled by liquid flowing in ducts 4. The film leaving the tube member 3 is then sprayed with cooling liquid from a plurality of nozzles 25 associated with trough 24.