Patent · US Expired

Hot pin parison injection molding technique

US4054630A · kind A · utility

11Cited by
13References
3Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJan 22, 1976
Grant dateOct 18, 1977
Priority date
Expiry dateJan 22, 1996

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB29K2105/253
  • WIPO fieldOther special machines
  • WIPO sectorMechanical engineering

Abstract

Parisons for use in making blow molded highly molecularly oriented plastic bottles are injection molded using a cooled cavity and a relatively hot core pin to prevent the formation of residual internal stress in or near the surface of the parison. The pin is maintained at a temperature above the glass transition temperature of the resin to reduce the formation of cracks when the parison is subsequently blow molded in the orientation temperature range.

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