×

Method of injection molding PVC products

  • US 4,792,424 A
  • Filed: 09/10/1985
  • Issued: 12/20/1988
  • Est. Priority Date: 01/10/1984
  • Status: Expired due to Fees
First Claim
Patent Images

1. The method of injection molding PVC products from powdered raw material while employing an injection molding machine of a two stage cascade type having an upper plasticizing double screw extruder and a lower injection apparatus having one injection screw, wherein the raw material is subjected to a prejellifying treatment during forced transportation of the powdered raw material through the upper plasticizing screw extruder unit in which it is heated and brought to an agglomerated state in a relatively short time, subjecting the plasticized material to a vacuum while passing through the lower injection unit.

View all claims
  • 1 Assignment
Timeline View
Assignment View
    ×
    ×