Patent · US Expired

Reflective data storage medium made by silver diffusion transfer

US4278756A · kind A · utility

61Cited by
12References
18Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 6, 1979
Grant dateJul 14, 1981
Priority date
Expiry dateJul 6, 1999

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S430/165
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A reflective laser recording and data storage medium, for direct reading after writing, formed from a photosensitive silver-halide emulsion wherein a surface latent image exposure on the recording area forms a depthwise gradient of silver nuclei. A single step negative silver diffusion transfer process is used to develop silver nuclei of the latent image and dissolve unexposed silver halide elsewhere, forming silver ion complexes. These complexes are transported by diffusion transfer to the developing silver nuclei sites where silver is precipitated and adsorbed to form a high concentration of non-filamentary particles at a surface of a low melting temperature dielectric matrix which is highly reflective of light and electrically non-conducting.

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