Patent · US Expired

Melt extrusion processing method of thermoplastic resin

US5928586A · kind A · utility

1Cited by
1References
4Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 17, 1997
Grant dateJul 27, 1999
Priority date
Expiry dateOct 17, 2017

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB29K2067/00
  • WIPO fieldOther special machines
  • WIPO sectorMechanical engineering

Abstract

A melt extrusion processing method of a thermoplastic resin, wherein a thermoplastic resin having a flow temperature of 200.degree. C. or higher is subjected to extrusion processing using a melt kneading type extruder in which a vent port is provided at a downstream position by length L from the most upper stream portion of a melt kneading type extruder screw and L/D is from 4 to 18 (wherein D indicates the screw diameter and D and L are in the same scale unit), while continuously sucking from the said vent port at a reduced pressure of lower then 660 mmHg. The invention provides a method which causes little resin degradation in an extruder to give an extruded article containing small amounts of discolored and degraded materials even when the processing is conducted for a relatively long time.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.