Highly absorptive dye-containing underlayer for laser recording and data storage media

• US 4,396,701 A
• Filed: 09/11/1981
• Issued: 08/02/1983
• Est. Priority Date: 09/11/1981
• Status: Expired due to Fees

• Current Assignee: LaserCard Corp. (Assa Abloy AB)
• Original Assignee: Drexler Technology Corporation (Assa Abloy AB)
• Inventors: Bouldin, Eric W.
• Primary Examiner(s): Schilling, Richard L.
• Application Number:
  US06/301,230
• Time in Patent Office: 690 Days
• Field of Search: 430/616, 430/414, 430/415, 430/416, 430/271, 430/320, 430/364, 430/495, 430/964, 430/517, 430/380, 430/384, 430/246, 430/214, 430/275, 346/76 L, 346/135.1
• US Class Current: 430/270.11
• CPC Class Codes: G03C 8/06 Silver salt diffusion transfer
• CPC Class Codes: G11B 7/251 comprising inorganic materials dispersed in an organic matrix
• CPC Class Codes: Y10S 430/165 Thermal imaging composition

Abstract

An underlayer for a laser recording and data storage medium with a light absorption characteristic suited to a recording laser. The underlayer is formed by creating a nuclei layer in a silver-halide photosensitive emulsion layer and then contacting the emulsion layer with a chromogenic reducing agent and a chromogenic dye coupler. The reflective layer may be formed prior to this step by subjecting the nuclei layer to a monobath having a silver-halide solvent and a silver reducing agent until a reflective surface layer of non-filamentary silver particles is formed, or after the step by chemical vapor deposition or sputtering of a reflective metal layer over the underlayer.

Claims

1. A reflective laser recording and optical data storage medium comprising,

a substrate supporting a colloid matrix layer, said colloid matrix layer having a reflective metal surface layer distal to the substrate and a light absorptive underlayer beneath the reflective metal surface layer, formed by black filamentary silver particles and light-absorbing in situ-formed organic dye molecules with an optical density gradient highest proximate to the reflective surface layer.

2. The medium of claim 1 where said reflective surface layer comprises non-filamentary silver particles and is electrically non-conductive.

3. The medium of claim 1 where said reflective surface layer comprises a reflective metal layer deposited over the colloid matrix layer.

8. The medium of claim 1 in which said reflective metal surface layer is electrically non-conductive.

4. A reflective laser recording and optical data storage medium comprising a substrate supporting a light-absorptive colloid matrix layer covered by a vapor-deposited reflective metal layer, said colloid matrix layer composed of black filamentary silver particles and in situ-formed light-absorptive organic dye molecules.

5. The medium of claim 4 in which the in situ-formed organic dye molecules are absorptive to red and infrared wavelengths.

6. The medium of claim 4 in which the in situ-formed organic dye molecules are absorptive to blue wavelength.

7. A reflective laser recording and optical data storage medium consisting of a thin reflective metal surface layer on an underlayer of colloid on a substrate in which the underlayer comprises light-absorptive black filamentary silver particles and in situ-formed organic dye molecules with an optical density gradient highest proximate to the reflective surface layer.

9. The medium of claim 7 in which said reflective metal surface layer is electrically non-conductive.