Patent · US Expired

Method for producing biaxially oriented hollow articles

US4496408A · kind A · utility

13Cited by
4References
20Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMar 28, 1983
Grant dateJan 29, 1985
Priority date
Expiry dateMar 28, 2003

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB29C2791/007
  • WIPO fieldOther special machines
  • WIPO sectorMechanical engineering

Abstract

Disclosed is a process for the production of a hollow article comprised of a biaxially oriented thermoplastic resinous material, comprising the steps of heating a sheet of thermoplastic material to a temperature above the orientation temperature of the thermoplastic material; clamping an area of the heated thermoplastic sheet between a first mold half and a second mold half, the first mold half containing a pre - form mold surface having a configuration predetermined to provide for uniform wall thickness of the hollow article to be formed, the surface being at a temperature which is not higher than the orientation temperature of the thermoplastic material, and the second mold half having a cavity which corresponds to the shape of the hollow article to be produced; forcing the heated thermoplastic sheet by pressure differential into the first mold half against the surface; maintaining the thermoplastic sheet in contact with the surface for a period of time sufficient to bring the thermoplastic sheet to its orientation temperature; and forcing the thermoplastic sheet into the second mold half by means of a pressure differential which is sufficient to cause the thermoplastic sheet to …

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