IP Library Granted Patent US 7,018,698
Granted Patent B2
US 7,018,698 · App. 10/900,108 · Granted Mar 28, 2006

Optical information recording medium

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Quick Facts
Patent No.
US 7,018,698
App. No.
10/900,108
Granted
Mar 28, 2006
Kind
B2
Abstract

To obtain an optical information recording medium which is highly sensitive and excellent in durability against repeated recording and which is excellent in storage stability. An optical information recording medium is employed which comprises a substrate, a recording layer, a sulfur-containing protective layer, an interface layer in contact with the protective layer and a reflective layer in contact with the interface layer and containing Ag as the main component, wherein the interface layer contains Nb and/or Mo as the main component. By providing such an interface layer, the reaction between the reflective layer and the protective layer is effectively suppressed.

Claims (9)

1. An optical information recording medium comprising a substrate, a recording layer, a sulfur-containing protective layer, an interface layer in contact with the protective layer and a reflective layer in contact with the interface layer and containing Ag as the main component, wherein the interface layer contains Nb and/or Mo as the main component.

2. The optical information recording medium according to claim 1 , wherein the interface layer has a light transmittance of at least 50% at the center wavelength of light to be used for recording on the optical information recording medium.

3. The optical information recording medium according to claim 1 , wherein the interface layer has a thickness of from 1 nm to 10 nm.

4. The optical information recording medium according to claim 1 , wherein the reflective layer contains at least 80 atomic % of Ag.

5. The optical information recording medium according to claim 4 , wherein the reflective layer contains, as an element other than Ag, at least one selected from the group consisting of Ti, V, Ta, Co, Cr, Si, Ge, Sn, Sc, Hf, Pd, Rh, Au, Pt, Mg, Zr, Cu, Mo and Mn.

6. The optical information recording medium according to claim 1 , wherein the sulfur in the protective layer is present in the form of a sulfide or an oxysulfide of any element selected from a rare earth element, Zn and Ta, in the protective layer.

7. The optical information recording medium according to claim 1 , wherein the recording layer has a composition containing Sb as the main component.

8. The optical information recording medium according to claim 7 , wherein the recording layer further contains Ge and/or Te, and the content of each of Ge and Te in the recording layer is from 1 atomic % to 30 atomic %.

9. The optical information recording medium according to claim 7 , wherein the recording layer further contains at least one of In, Ga and Sn, and the content of each of In, Ga and Sn in the recording layer is from 1 atomic % to 30 atomic %.

Assignments (6)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jan 23, 2020
From: MITSUBISHI CHEMICAL MEDIA CO., LTD.
To: CMC MAGNETICS CORPORATION
Reel/Frame 051688/0598 →
CHANGE OF ADDRESS Recorded Nov 11, 2019
From: MITSUBISHI KAGAKU MEDIA CO., LTD.
To: MITSUBISHI KAGAKU MEDIA CO., LTD.
Reel/Frame 050977/0911 →
CHANGE OF NAME Recorded Nov 11, 2019
From: MITSUBISHI KAGAKU MEDIA CO., LTD.
To: MITSUBISHI CHEMICAL MEDIA CO., LTD.
Reel/Frame 050978/0091 →
CHANGE OF ADDRESS Recorded Nov 11, 2019
From: MITSUBISHI KAGAKU MEDIA CO., LTD.
To: MITSUBISHI KAGAKU MEDIA CO., LTD.
Reel/Frame 051015/0856 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jan 23, 2006
From: MITSUBISHI CHEMICAL CORPORATION
To: MITSUBISHI KAGAKU MEDIA CO., LTD.
Reel/Frame 017198/0939 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jul 28, 2004
From: MIZUNO, MASAAKI; HOSHINO, HIROYUKI; HORIE, MICHIKAZU
To: MITSUBISHI CHEMICAL CORPORATION
Reel/Frame 015631/0975 →