Patent US1354123A successfully refreshed from Google Patents.
US3557261A
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Method of centrifugally casting layered contact lenses
Assignee: Czech Academy of Sciences
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Filing: 1967-10-05
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Granted: 1971-01-19
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Expires: 1987-10-05
Abstract
Abstract A MIXTURE OF ETHYLENEGLYCOL MONOMETHACRYLATE WITH A LITTLE ETHYLENEGLYCOL DIMETHYACRYLATE IS POLYMERIZED IN A MOLD ROTATING ABOUT AN AXIS PERPENDICULAR TO A SPHERICALLY CONCAVE MOLD FACE TO FORM A SHAPE-RETAINING HYDROPHILIC POLYMER LAYER. A VERY THIN LAYER OF OPAQUE MATTER IS DEPOSITED ON THE EXPOSED POLYMER FACE AND COVERED WITH A SECOND LAYER OF THE SAME POLYMER. THE OPAQUE MATERIAL MAY SIMULATE THE IRIS, PUPIL, AND/OR SCLERA OF AN EYE WHEN THE LAMINAR PRODUCT IS ULTIMATELY SWELLED BY CONTACT WITH PHYSIOLOGICAL SALINE SOLUTION PRIOR TO USE AS SOFT CONTACT LENS OR AS PART OF AN ARTIFICAL EYE.
Inventors
- 👤 Otto Wichterle
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 12:28
CPC Classifications
B; B29; B29D; B29D11/00; B29D11/0073; B29C; B29C39/00; B29C39/003; B29C39/006; B29C41/00; B29C41/003; B29C41/02; B29C41/04; B29C41/042; B29C41/045; B29C41/22; B29D11/00009; B29D11/00038; B29D11/00048; B29D11/00317; B29D11/00471; B29D11/00865; B29D11/00894; B29K; B29K2033/00; B29K2033/04; B29K2033/12; B29K2105/00; B29K2105/0002; B29K2995/00; B29K2995/0018; B29K2995/0025; B29L; B29L2011/00; B29L2011/0016; B29L2011/0041; B29L2031/00; B29L2031/76
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-01-18 | 1974-07-20 | 1975-01-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-01-18 | 1978-07-20 | 1979-01-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-01-18 | 1982-07-20 | 1983-01-19 | $7700.00 | Window Closed / Lapsed |