US3608057A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for making contact lenses
Assignee: Amicon Corp
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Filing: 1967-10-03
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Granted: 1971-09-21
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Expires: 1987-10-03
Abstract
Abstract A process for making an article, and the articles formed thereby from an ionically cross-linked polymer; said process comprising the essential steps of forming a composition comprising a said polymer and a nonvolatile organic plasticizer therefor, forming said article by molding and/or machining steps, leaching said plasticizer from the formed article, and replacing it with water or an aqueous solution. The process is particularly useful in the manufacture of a novel contact lens because it results in articles of unexpectedly good color characteristics and a high water content which had never before been achieved.
Inventors
- 👤 Harris J Bixler
- 👤 Mary Ann Kendrick
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 23:55
CPC Classifications
C; C08; C08J; C08J5/00; C08J3/00; C08J3/24; C08J3/246
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
31 words
A process as defined in claim 1 whereby said substituting steps are accomplished by equilibrating the resin in a bath of the liquid with which the substitution is to be made.
Claim 2
Dependent Claim
12 words
A process as defined in claim 1 wherein the plasticizer is glycerine.
Claim 3
Dependent Claim
26 words
A process as defined in claim 1 wherein the polyelectrolyte complex resin is a complex of poly (sodium styrene sulfonate) and poly (vinyl benzyltrimethyl (ammonium chloride).
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) | 1974-09-20 | 1975-03-22 | 1975-09-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-09-20 | 1979-03-22 | 1979-09-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-09-20 | 1983-03-22 | 1983-09-21 | $7700.00 | Window Closed / Lapsed |