US4668550A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Optical disc
Assignee: Hitachi Ltd
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Filing: 1986-06-26
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Granted: 1987-05-26
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Expires: 2006-06-26
Abstract
Abstract Optical discs obtained by using as a primer layer formed on a transparent substrate and under a metal-made recording film a cured ultraviolet-curable resin composition comprising (a) a reaction product of isophorone diisocyanate or the like and an acrylate or methacrylate, (b) a diacrylate or dimethacrylate and (c) a photopolymerization initiator are excellent in recording sensitivity, moisture resistance, heat resistance, adhesive properties, reliability, etc.
Inventors
- 👤 Tetsuo Tajima
- 👤 Hiroaki Miwa
- 👤 Ryoichi Sudo
- 👤 Shinkichi Horigome
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 09:31
CPC Classifications
G; G11; G11B; G11B7/00; G11B7/24; G11B7/241; G11B7/252; G11B7/256; G11B7/242; G11B7/243; G11B2007/24302; G11B2007/2431; G11B2007/24312; G11B2007/24314; G11B2007/24316; G11B7/253; G11B7/2531; G11B7/2533; Y; Y10; Y10S; Y10S430/00; Y10S430/146; Y10T; Y10T428/00; Y10T428/31504; Y10T428/31551; Y10T428/31605
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
166 words
In an optically readable information disc comprising a transparent substrate, a primer layer formed on the substrate and having a relief structure corresponding to information signals to be carried, and a metal-made recording film layer formed on the primer layer, the improvement wherein the primer layer is obtained by curing an ultraviolet-curable resin composition comprising (a) 20 to 80 parts by weight of a compound of the formula: ##STR26## wherein R 1 is hydrogen or a methyl group; R 2 and R 3 are independently hydrogen, or an alkyl group having 1 to 8 carbon atoms; and R 4 is ##STR27## (b) 80 to 20 parts by weight of a compound of the formula: ##STR28## wherein R 1 and R 5 are independently hydrogen or a methyl group; and n is an integer of 5 to 12, and (c) a photopolymerization initiator in an amount of 0.1 to 5.0 parts by weight per 100 parts by weight of the total of the components (a) and (b).
Claim 2
Dependent Claim
166 words
In an optically readable information disc comprising a transparent substrate, a primer layer formed on the substrate and having a relief structure corresponding to information signals to be carried, and a metal-made recording film layer formed on the primer layer, the improvement wherein the primer layer is obtained by curing an ultraviolet-curable resin composition comprising (a) 20 to 80 parts by weight of a compound of the formula: ##STR26## wherein R 1 is hydrogen or a methyl group; R 2 and R 3 are independently hydrogen, or an alkyl group having 1 to 8 carbon atoms; and R 4 is ##STR27## (b) 80 to 20 parts by weight of a compound of the formula: ##STR28## wherein R 1 and R 5 are independently hydrogen or a methyl group; and n is an integer of 5 to 12, and (c) a photopolymerization initiator in an amount of 0.1 to 5.0 parts by weight per 100 parts by weight of the total of the components (a) and (b).
Claim 3
Dependent Claim
18 words
An optically readable information disc according to claim 1, wherein R 4 in the formula (1) is ##STR29##
Claim 4
Dependent Claim
47 words
An optically readable information disc according to claim 1, wherein the compound of the formula (1) is at least one member selected from the group consisting of ##STR30## wherein R 1 is hydrogen or a methyl group; m is zero or an integer of 1 to 8.
Claim 5
Dependent Claim
21 words
An optically readable information disc according to claim 3, wherein as the compound of the formula (2) there is used ##STR31##
Claim 6
Dependent Claim
18 words
An optically readable information disc according to claim 1, wherein the compound of the formula (1) is ##STR32##
Claim 7
Dependent Claim
27 words
An optically readable information disc according to claim 1, wherein the compound of the formula (1) is ##STR33## and the compound of the formula (2) is ##STR34##
Claim 8
Dependent Claim
27 words
An optically readable information disc according to claim 1, wherein the compound of the formula (1) is ##STR35## and the compound of the formula (2) is ##STR36##
Claim 9
Dependent Claim
22 words
An optically readable information disc according to claim 1, wherein the compound of the formula (1) is ##STR37## or a mixture thereof.
Claim 10
Dependent Claim
22 words
An optically readable information disc according to claim 1, wherein the compound of the formula (1) is ##STR38## or a mixture thereof.
References Cited (Backward Citations)
US4456659A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-05-25 | 1990-11-24 | 1991-05-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-05-25 | 1994-11-24 | 1995-05-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-05-25 | 1998-11-24 | 1999-05-26 | $7700.00 | Window Closed / Lapsed |