US5244706A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Optical recording disk
Assignee: TDK Corp
•
Filing: 1992-02-25
•
Granted: 1993-09-14
•
Expires: 2012-02-25
Abstract
Abstract An optical recording disk includes a resin substrate having a recording layer thereon and a protective glass substrate, which are joined into an integral disk such that the recording layer is inside. The resin substrate is formed of a resin composition comprising a specific cyclic polyolefin and an optional alkyl phenol condensate. The resulting lightweight, rigid disk is adapted for recording/reproducing operation at high rotational speeds with few focusing errors due to minimized axial runouts.
Inventors
- 👤 Hideki Hirata
- 👤 Toshifumi Tanaka
- 👤 Setsuko Shibuya
- 👤 Atsuko Motai
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 09:29
CPC Classifications
G; G11; G11B; G11B7/00; G11B7/24; G11B7/241; G11B7/252; G11B7/253; G11B7/2531; G11B7/2533; G11B7/242; G11B7/243; G11B2007/24302; G11B2007/24304; G11B7/2433; G11B7/244; G11B7/246; G11B7/2534; G11B7/2538; G11B7/254; G11B7/2542; G11B7/256; G11B7/257; G11B7/2578; G11B7/258; G11B7/259; G11B7/2595; Y; Y10; Y10S; Y10S428/00; Y10S428/913; Y10S430/00; Y10S430/146; Y10T; Y10T428/00; Y10T428/24; Y10T428/24942; Y10T428/31504; Y10T428/31678
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
173 words
An optical recording disk comprising a resin substrate, a recording layer on the resin substrate, and a protective glass substrate, the resin and glass substrate being joined into an integral disk such that the recording layer is inside; said resin substrate including a skin layer under the surface thereof bearing the recording layer and said skin layer having a thermal softening point of about 100 to 140 degrees C., said resin substrate further having the softening of the skin layer and a secondary thermal softening point by at least 10 degrees C. higher than the skin layer thermal softening point; said resin substrate being formed of a resin composition comprising the cyclic polyolefin having a recurring structural unit of the formula: ##STR4## wherein q is equal to 0 or a positive integer, R 1 and R 2 are independently selected from the group consisting of a hydrogen atom, halogen atom, hydrogen group, ester group, nitrile group, and the heterocyclic group, and R 1 and R 2 , taken together, may form a ring.
Claim 2
Dependent Claim
173 words
An optical recording disk comprising a resin substrate, a recording layer on the resin substrate, and a protective glass substrate, the resin and glass substrate being joined into an integral disk such that the recording layer is inside; said resin substrate including a skin layer under the surface thereof bearing the recording layer and said skin layer having a thermal softening point of about 100 to 140 degrees C., said resin substrate further having the softening of the skin layer and a secondary thermal softening point by at least 10 degrees C. higher than the skin layer thermal softening point; said resin substrate being formed of a resin composition comprising the cyclic polyolefin having a recurring structural unit of the formula: ##STR4## wherein q is equal to 0 or a positive integer, R 1 and R 2 are independently selected from the group consisting of a hydrogen atom, halogen atom, hydrogen group, ester group, nitrile group, and the heterocyclic group, and R 1 and R 2 , taken together, may form a ring.
Claim 3
Dependent Claim
21 words
The optical recording disk of claim 1 wherein recording/reproducing operation is performed while rotating the disk at 1,800 rpm or higher.
Claim 4
Dependent Claim
19 words
The optical recording disk of claim 1 wherein said resin substrate is formed by injection molding the resin composition.
Claim 5
Dependent Claim
26 words
The optical recording disk of claim 1 wherein said recording layer contains a dye, and said disk further includes a reflective layer on said recording layer.
Claim 6
Dependent Claim
24 words
The optical recording disk of claim 1 wherein said recording layer is formed directly on said resin substrate by a vapor phase deposition method.
Claim 7
Dependent Claim
36 words
The optical recording disk of claim 1 which further includes an undercoat layer between said resin substrate and said recording layer, wherein said recording and undercoat layers each are formed by a vapor phase deposition method.
Claim 8
Dependent Claim
22 words
The optical recording disk of claim 1 wherein said resin composition contains 0 to 2% by weight of an alkyl phenol condensate.
References Cited (Backward Citations)
US4994354A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1996-09-13 | 1997-03-15 | 1997-09-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-09-13 | 2001-03-15 | 2001-09-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-09-13 | 2005-03-15 | 2005-09-14 | $7700.00 | Window Closed / Lapsed |