Patent · US Expired

Plastic casting molds

US6638451B1 · kind B1 · utility

18Cited by
15References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 25, 2000
Grant dateOct 28, 2003
Priority date
Expiry dateAug 25, 2020

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S522/907
  • WIPO fieldOther special machines
  • WIPO sectorMechanical engineering

Abstract

The invention is concerned with the problem that with known plastic casting molds, especially those of polypropylene, the lenses produced with these molds have a slippery surface. The invention solves this problem through the use of polymers which are notable for their very low oxygen permeability.

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