Patent US4693939A successfully refreshed from Google Patents.
US4693939A
Expired / Lapsed
US
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Article coated with copolymer of poly(vinyl alcohol)
Assignee: 3M Co
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Filing: 1986-09-03
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Granted: 1987-09-15
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Expires: 2006-09-03
Abstract
Abstract Novel, non-crosslinked copolymers of vinyl trifluoroacetate (VTA) and up to 5 weight percent of the VTA of certain comonomers, such as vinyl esters, vinyl ethers, or disubstituted ethylene monomers, are disclosed. Solvolysis of these copolymers provides novel water-insoluble, non-crosslinked, poly(vinyl alcohol) copolymers which can be hydrated to copolymers having controllably variable hydrogel properties and high strength. Such poly(vinyl alcohol) copolymers are particularly desirable as ophthalmic devices such as contact lenses, corneal implants and transplants, and intraocular lenses.
Inventors
- 👤 Ronald F. Ofstead
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 18:50
CPC Classifications
G; G02; G02B; G02B1/00; G02B1/04; G02B1/041; G02B1/043; C; C08; C08F; C08F218/00; C08F218/02; C08F218/04; C08F8/00; C08F8/44; C08J; C08J5/00; C08J5/18; C08F2810/00; C08F2810/50; Y; Y10; Y10T; Y10T428/00; Y10T428/31504; Y10T428/3154
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
40 words
An article having a coating comprising a non-crosslinked poly(vinyl alcohol) copolymer which is the reaction product of: a. a non-crosslinked poly(vinyl trifluoroacetate) copolymer having a molecular weight in the range of 200,000 to 4,000,000 which is the reaction product of:
Claim 2
Dependent Claim
40 words
An article having a coating comprising a non-crosslinked poly(vinyl alcohol) copolymer which is the reaction product of: a. a non-crosslinked poly(vinyl trifluoroacetate) copolymer having a molecular weight in the range of 200,000 to 4,000,000 which is the reaction product of:
Claim 3
Dependent Claim
55 words
95 to 99.99 weight percent of vinyl trifluoroacetate monomer, and 2. 0.01 to 5 weight percent of a comonomer selected from vinyl esters, vinyl ethers, and copolymerizable disubstituted ethylenes; and b. a mild base in a non-aqueous diluent selected so that the poly(vinyl trifluoroacetate) copolymer and its poly(vinyl alcohol) copolymer solvolysis product are insoluble therein.
Claim 4
Dependent Claim
55 words
95 to 99.99 weight percent of vinyl trifluoroacetate monomer, and 2. 0.01 to 5 weight percent of a comonomer selected from vinyl esters, vinyl ethers, and copolymerizable disubstituted ethylenes; and b. a mild base in a non-aqueous diluent selected so that the poly(vinyl trifluoroacetate) copolymer and its poly(vinyl alcohol) copolymer solvolysis product are insoluble therein.
Claim 5
Dependent Claim
19 words
The article according to claim 1 wherein said non-aqueous mild base is selected from ammonium hydroxide and organic amines.
Claim 6
Dependent Claim
40 words
The article according to claim 1 wherein said poly(vinyl alcohol) copolymer comprises 85 to 99.97 weight percent of vinyl alcohol monomer units and 0.03 to 15 weight percent of comonomer units derived from vinyl esters, vinyl ethers, and disubstituted ethylenes.
Claim 7
Dependent Claim
19 words
The article according to claim 1 wherein said poly(vinyl alcohol) copolymer contains vinyl alcohol and vinyl acetate monomer units.
Claim 8
Dependent Claim
14 words
The article according to claim 1 wherein said poly(vinyl alcohol) copolymer is a hydrogel.
Claim 9
Dependent Claim
22 words
The article according to claim 1 wherein said poly(vinyl alcohol) copolymer has a tensile strength of at least 6.9 kg/cm 2 .
Claim 10
Dependent Claim
11 words
The article according to claim 1 which is a shaped article.
Claim 11
Dependent Claim
12 words
The shaped article according to claim 7 which is an ophthalmic device.
Claim 12
Dependent Claim
12 words
The shaped article according to claim 8 which is a contact lens.
Claim 13
Dependent Claim
12 words
The shaped article according to claim 8 which is an intraocular lens.
Claim 14
Dependent Claim
12 words
The shaped article according to claim 8 which is a corneal transplant.
Claim 15
Dependent Claim
12 words
The shaped article according to claim 8 which is a corneal implant.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-09-14 | 1991-03-16 | 1991-09-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-09-14 | 1995-03-16 | 1995-09-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-09-14 | 1999-03-16 | 1999-09-15 | $7700.00 | Window Closed / Lapsed |