US4424335A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Keratoprosthetic polyurethane
Assignee: Thermo Fisher Scientific Inc
•
Filing: 1982-07-19
•
Granted: 1984-01-03
•
Expires: 2002-07-19
Abstract
Abstract A reaction product of 4,4' dicyclohexylmethane diisocyanate, polytetramethylene ether glycol and ethylene oxide-capped trimethylol propane. The resulting polyurethane is optically clear and suitable for use as an artificial cornea, or a permanently implantable lens.
Inventors
- 👤 Michael Szycher
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 23:48
CPC Classifications
C; C08; C08G; C08G18/00; C08G18/06; C08G18/28; C08G18/65; C08G18/66; C08G18/6666; C08G18/667; C08G18/6674; C08G18/6677; A; A61; A61F; A61F2/00; A61F2/02; A61F2/14; A61F2/142; A61F2/16; B; B29; B29D; B29D11/00; B29D11/02; B29D11/023; C08G18/70; C08G18/72; C08G18/74; C08G18/75; C08G18/758; G; G02; G02B; G02B1/00; G02B1/04; G02B1/041; G02B1/043
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
49 words
A polyurethane elastomer, said polyurethane elastomer being the reaction product of, 2.2 equivalent weights of 4,4' dicyclohexylmethane diisocyanate, 1.0 equivalent weights of polytetramethylene ether glycol wherein the molecular weight of said polytetramethylene ether glycol is between the range of 1000-3000, and 1.0 equivalent weights of ethylene oxide-capped trimethylol propane.
Claim 2
Dependent Claim
49 words
A polyurethane elastomer, said polyurethane elastomer being the reaction product of, 2.2 equivalent weights of 4,4' dicyclohexylmethane diisocyanate, 1.0 equivalent weights of polytetramethylene ether glycol wherein the molecular weight of said polytetramethylene ether glycol is between the range of 1000-3000, and 1.0 equivalent weights of ethylene oxide-capped trimethylol propane.
Claim 3
Dependent Claim
37 words
A polyurethane elastomer having the following formula: ##STR5## where n 1 , n 2 and n 3 are positive integers between the range of 25-30 and n 4 is a positive integer between the range of 100-300.
Claim 4
Dependent Claim
37 words
A polyurethane elastomer having the following formula: ##STR5## where n 1 , n 2 and n 3 are positive integers between the range of 25-30 and n 4 is a positive integer between the range of 100-300.
References Cited (Backward Citations)
US2542386A
Cited
US2948691A
Cited
US2929800A
Cited
US2714721A
Cited
US2866774A
Cited
US2754520A
Cited
US2865940A
Cited
US2808391A
Cited
US2808967A
Cited
US2899411A
Cited
US2952023A
Cited
US3012987A
Cited
US3130175A
Cited
GB976902A
Cited
US3336242A
Cited
GB980435A
Cited
US3208957A
Cited
GB1075467A
Cited
US3458870A
Cited
US3454966A
Cited
US3512183A
Cited
US3760045A
Cited
US3487050A
Cited
GB1240116A
Cited
US3562352A
Cited
US3635904A
Cited
US3604016A
Cited
GB1323766A
Cited
US3746683A
Cited
GB1351774A
Cited
GB1351773A
Cited
GB1401986A
Cited
US4002169A
Cited
US3804812A
Cited
US3798200A
Cited
US3939021A
Cited
US3961379A
Cited
GB1529319A
Cited
US4131604A
Cited
US4131605A
Cited
US4285073A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-01-02 | 1987-07-04 | 1988-01-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-01-02 | 1991-07-04 | 1992-01-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-01-02 | 1995-07-04 | 1996-01-03 | $7700.00 | Window Closed / Lapsed |