Method and apparatus for quenching polymeric films

Abstract

Abstract 1,194,486. Production and handling of films. CELANESE CORP. 3 April, 1968 [10 April, 1967], No. 16952/68. Heading B5B. In an apparatus for producing or handling an electrically insulating film, in which the film is pressed against a metallic surface by force arising from an electrostatic charge applied to the film, the electrostatic charge is developed by an ionizing discharge between an electrode connected to one terminal of a high voltage source and both an electrically conducting element connected to the other terminal of the high voltage source and the metallic surface, the latter surface being connected to the element by a current limiting resistance and being situated closer to the electrode than is the element. The element is preferably a film extrusion die arranged to deposit film extruded on to the metallic surface of a rotatable drum, and is connected with the corresponding terminal of the high voltage supply to earth. As shown, the film extruding plant comprises an extruder die 10 electrically earthed, a casting drum 12 upon the polished surface of which the film from die 10 is deposited and a take-off roll 18. The rotatable drum 12 is earthed through a current limiting resistance R 3 which avoids arcing between the electrode and the metal surface. The positive terminal of a high voltage direct current supply 16 is connected directly to electrode 14 and its negative terminal to earth. Film extruded from die 10, in travelling to drum 12, collects a positive charge and is attracted to the drum's surface and pressed against it.

Inventors

• 👤 Joseph B Busby

Bibliographic Details