Patent · US Expired

Photochromic sheet glass process

US4204027A · kind A · utility

22Cited by
15References
9Claims
0Family size

Assignee

Inventor

Key dates

Filing dateApr 5, 1979
Grant dateMay 20, 1980
Priority date
Expiry dateApr 5, 1999

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S428/913
  • WIPO fieldOther special machines
  • WIPO sectorMechanical engineering

Abstract

A relatively thin layer of molten photochromic glass is formed on the surface of a relatively thick molten core glass of greater viscosity than that of the photochromic glass as such core glass is drawn into sheet form. The core glass is selected for its viscosity-temperature characteristics such that the core glass will support the photochromic surface glass during the temperature cycle required for developing the photochromic properties of such surface glass.

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