US2858240A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Thin films, film coated articles and methods of making same
Assignee: Bausch and Lomb Inc
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Filing: 1953-05-18
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Granted: 1958-10-28
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Expires: 1973-05-18
Abstract
No abstract record available.
Inventors
- 👤 Arthur F Turner
- 👤 Frank K Turby
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:22
CPC Classifications
C; C03; C03C; C03C17/00; C03C17/34; C03C17/3411; C03C17/3429; C03C17/3464; C03C17/347; C03C17/3447; C03C17/3452; G; G02; G02B; G02B5/00; G02B5/20; G02B5/28; G02B5/285; Y; Y10; Y10T; Y10T428/00; Y10T428/26; Y10T428/261
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
118 words
THE METHOD OF MAKING A STRESS-FREE SHEET OF FILMS WHICH COMPRISES FORMING A SET OF FILMS BY DEPOSITING ON A BASE A FIRST NON-METALLIC INORGANIC FILM WHICH HAS AN INTERNAL STRESS AND A THICKNESS OF LESS THAN 100 QUARTER WAVE LENGTHS OF LIGHT AT 546 MILLIMICRONS, DEPOSITING ON SAID FIRST FILM A SECOND NON-METALLIC INORGANIC FILM WHICH HAS A INTERNAL STRESS OPPOSITE TO THAT IN THE FIRST FILM AND A THICKNESS OF LESS THAN 100 QUARTER WAVE LENGTHS OF LIGHT 546 MILLIMICRONS, CONTROLLING THE RELATIVE THICKNESSES OF THE FILMS TO RENDER THE STRESSES IN THE SET SUBSTANTIALLY EQUAL, DEPOSITING ADDITIONAL STRESS-FREE SETS OF FILMS ON THE FIRST NAMED SET AND REMOVING THE SHEET OF FILMS FROM THE BASE.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-10-27 | 1962-04-28 | 1962-10-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-10-27 | 1966-04-28 | 1966-10-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-10-27 | 1970-04-28 | 1970-10-28 | $7700.00 | Window Closed / Lapsed |