US4346469A
Expired / Lapsed
US
⏱️ 0.0 years remaining
High density information disc
Assignee: RCA Corp
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Filing: 1981-07-20
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Granted: 1982-08-24
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Expires: 2001-07-20
Abstract
Abstract High density information discs comprising a conductive carbon-loaded polyvinylchloride disc lubricated with a fractionated methyl alkyl siloxane lubricant which contains a hexaalkyldisilazane additive.
Inventors
- 👤 Louis J. Hillenbrand
- 👤 Joseph R. Preston
- 👤 David A. Berry
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 10:24
CPC Classifications
G; G11; G11B; G11B3/00; G11B3/68; G11B3/682; C; C08; C08L; C08L83/00; C08L83/04; Y; Y10; Y10T; Y10T428/00; Y10T428/31504; Y10T428/31652; Y10T428/31663; Y10T428/31667
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
175 words
In a high density information record adapted for use with a playback stylus to effect recovery of signals occupying a bandwidth of at least several megahertz when relative motion at a desired rate is established between said record and said stylus, said record comprising a disc of a conductive material containing an information track constituted by a surface relief pattern in said track to accommodate recovery of signals of said bandwidth upon establishment of relative motion at said rate, said record coated with a methyl alkyl siloxane lubricant having the formula ##STR4## wherein R 1 and R 2 are alkyl groups of 4-20 carbon atoms, x is an integer of 2-4, y is an integer of 0-2 and wherein the sum of x plus y is 4 or less, the improvement which comprises adding to said lubricant a hexaalkyldisilazane additive of the formula ##STR5## wherein R 3 and R 4 independently are alkyl groups of 1-5 carbon atoms and R 5 is selected from the group consisting of hydrogen or alkyl of 1-5 carbon atoms.
Claim 2
Dependent Claim
175 words
In a high density information record adapted for use with a playback stylus to effect recovery of signals occupying a bandwidth of at least several megahertz when relative motion at a desired rate is established between said record and said stylus, said record comprising a disc of a conductive material containing an information track constituted by a surface relief pattern in said track to accommodate recovery of signals of said bandwidth upon establishment of relative motion at said rate, said record coated with a methyl alkyl siloxane lubricant having the formula ##STR4## wherein R 1 and R 2 are alkyl groups of 4-20 carbon atoms, x is an integer of 2-4, y is an integer of 0-2 and wherein the sum of x plus y is 4 or less, the improvement which comprises adding to said lubricant a hexaalkyldisilazane additive of the formula ##STR5## wherein R 3 and R 4 independently are alkyl groups of 1-5 carbon atoms and R 5 is selected from the group consisting of hydrogen or alkyl of 1-5 carbon atoms.
Claim 3
Dependent Claim
19 words
A record according to claim 1 wherein R 3 and R 4 are methyl and R 5 is hydrogen.
Claim 4
Dependent Claim
25 words
A record according to claim 1 wherein from about 5 to about 20 percent by weight of the lubricant of the hexaalkyldisilazane additive is present.
Claim 5
Dependent Claim
23 words
A record according to claim 1, 2 or 3 wherein said disc is made of a conductive carbon-containing polymer or copolymer of polyvinylchloride.
References Cited (Backward Citations)
US3833408A
Cited
US4275101A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-08-23 | 1986-02-22 | 1986-08-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-08-23 | 1990-02-22 | 1990-08-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-08-23 | 1994-02-22 | 1994-08-24 | $7700.00 | Window Closed / Lapsed |