EP0406569A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Optical recording medium
Assignee: Teijin Ltd
•
Filing: 1990-06-02
•
Granted: —
•
Expires: 2010-06-02
Abstract
Abstract A metal reflecting layer (5) of an aluminum or silver alloy containing gold has a lower thermal conductivity than aluminum or silver and gold while maintaining a high reflectivity, and thus an optical recording medium, particularly a magneto-optical recording medium, having a high recording sensitivity and a C/N ratio, as well as an improved durability, can be provided. The content of Au in the Al alloy is 0.5 - 20 at% and that in the silver alloy is 0.5 - 30 at%. Preferably, at least one of the group consisting of titanium, tantalum, zirconium and yittrium is added to an alloy of Al or Ag with Au, and the content of at least one of the group consisting of titanium, tantalum, zirconium and yittrium is preferably 0.3 - 5.0 at% in an Al-Au alloy and 0.3 - 12.0 at% in an Ag-Au alloy. More preferably, the total content of Au and at least one of the group consisting of titanium, tantalum, zirconium and yittrium is 1.0 - 15 at%.
Inventors
- 👤 Kazutomi Suzuki
- 👤 Takashi Tomie
- 👤 Chiba Kiyoshi
- 👤 Tadanori Nakatani
- 👤 Kimio Kinoshita
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-01 23:25
CPC Classifications
G; G11; G11B; G11B11/00; G11B11/10; G11B11/105; G11B11/10582; G11B11/10586; G11B7/00; G11B7/24; G11B7/241; G11B7/252; G11B7/258; G11B7/242; G11B7/243; G11B2007/24302; G11B2007/24306; G11B7/253; G11B7/2533; G11B7/2534; G11B7/2585; G11B7/259; G11B7/2595; Y; Y10; Y10S; Y10S428/00; Y10S428/913; Y10S430/00; Y10S430/146; Y10T; Y10T428/00; Y10T428/31504; Y10T428/31678
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
45 words
An optical recording medium comprising: a transparent substrate; an optical recording layer deposited over the substrate; and a metal reflecting layer deposited over the optical recording layer; wherein the metal reflecting layer consists essentially of an alloy of aluminum with 0.5 to 20 at% gold.
Claim 2
Dependent Claim
45 words
An optical recording medium comprising: a transparent substrate; an optical recording layer deposited over the substrate; and a metal reflecting layer deposited over the optical recording layer; wherein the metal reflecting layer consists essentially of an alloy of aluminum with 0.5 to 20 at% gold.
Claim 3
Dependent Claim
17 words
A medium according to claim 1 wherein the content of the gold is 0.5 to 15 at%.
Claim 4
Dependent Claim
33 words
A medium according to claim 1, wherein the metal reflecting layer further contains 0.3 to 5.0 at% of at least one element selected from the group consisting of titanium, tantalum, zirconium and yittrium.
Claim 5
Dependent Claim
34 words
A medium according to claim 3, wherein the total content of the gold and at least one element selected from the group consisting of titanium, tantalum, zirconium and yittrium is 1.0 to 15.0 at%.
Claim 6
Dependent Claim
19 words
A medium according to claim 1, wherein the metal reflecting layer is in contact with the optical recording layer.
Claim 7
Dependent Claim
22 words
A medium according to claim 1, further comprising a transparent dielectric layer deposited between the optical recording layer and the transparent substrate.
Claim 8
Dependent Claim
23 words
A medium according to claim 1, further comprising a transparent dielectric layer deposited between the metal reflecting layer and the optical recording layer.
Claim 9
Dependent Claim
18 words
A medium according to claim 1, further comprising an inorganic protecting layer deposited over the metal reflecting layer.
Claim 10
Dependent Claim
16 words
A medium according to claim 1, wherein the optical recording layer is a magneto-optical recording layer.
Claim 11
Dependent Claim
20 words
A medium according to claim 3, wherein the metal reflecting layer is an alloy of aluminium with gold and titanium.
Claim 12
Dependent Claim
82 words
A dedium according to claim 9, comprising: a transparent substrate; a first transparent dielectric layer of a nitride on the transparent substrate; a magneto-optical recording layer on the first transparent dielectric layer; a second transparent dielectric layer of a nitride on the magneto-optical recording layer; a metal reflecting layer on the second transparent recording layer, the metal reflecting layer consisting essentially of an alloy of aluminum with 0.5 to 20 at% gold; and an inorganic protecting layer on the metal reflecting layer.
Claim 13
Dependent Claim
45 words
An optical recording medium comprising: a transparent substrate; an optical recording layer deposited over the substrate; and a metal reflecting layer deposited over the optical recording layer; wherein the metal reflecting layer consists essentially of an alloy of silver with 0.5 to 30 at% gold.
Claim 14
Dependent Claim
45 words
An optical recording medium comprising: a transparent substrate; an optical recording layer deposited over the substrate; and a metal reflecting layer deposited over the optical recording layer; wherein the metal reflecting layer consists essentially of an alloy of silver with 0.5 to 30 at% gold.
Claim 15
Dependent Claim
17 words
A medium according to claim 12, wherein the content of the gold is 0.5 to 15 at%.
Claim 16
Dependent Claim
33 words
A medium according to claim 12, wherein the metal reflecting layer further contains 0.3 to 12.0 at% of at least one element selected from the group consisting of titanium, tantalum, zirconium and yittrium.
Claim 17
Dependent Claim
34 words
A medium according to claim 14, wherein the total content of the gold and at least one element selected from the group consisting of titanium, tantalum, zirconium and yittrium is 1.0 to 15.0 at%.
Claim 18
Dependent Claim
18 words
A medium according to claim 12, wherein the metal reflecting layer is in contact with the recording layer.
Claim 19
Dependent Claim
22 words
A medium according to claim 12, further comprising a transparent dielectric layer deposited between the optical recording layer and the transparent substrate.
Claim 20
Dependent Claim
23 words
A medium according to claim 12, further comprising a transparent dielectric layer deposited between the metal reflecting layer and the optical recording layer.
Claim 21
Dependent Claim
18 words
A medium according to claim 12, further comprising an inorganic protecting layer deposited over the metal reflecting layer.
Claim 22
Dependent Claim
16 words
A medium according to claim 12, wherein the optical recording layer is a magneto-optical recording layer.
Claim 23
Dependent Claim
20 words
A medium according to claim 14 wherein the metal reflecting layer is an alloy of silver with gold and titanium.
Claim 24
Dependent Claim
82 words
A dedium according to claim 20, comprising: a transparent substrate; a first transparent dielectric layer of a nitride on the transparent substrate; a magneto-optical recording layer on the first transparent dielectric layer; a second transparent dielectric layer of a nitride on the magneto-optical recording layer; a metal reflecting layer on the second transparent recording layer, the metal reflecting layer consisting essentially of an alloy of silver with 0.5 to 30 at% gold; and an inorganic protecting layer on the metal reflecting layer.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.