US4904708A
Expired / Lapsed
US
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Method of manufacturing soft contact lens material
Assignee: Tokyo Contact Lens Research Institute
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Filing: 1988-05-31
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Granted: 1990-02-27
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Expires: 2008-05-31
Abstract
Abstract Hydrophilic monomers in a supercooled, transparent state, are polymerized in the presence of water. The polymers have low levels of residual monomers and exhibit good mechanical strength. The process provides materials useful as contact lenses.
Inventors
- 👤 Isao Kaetsu
- 👤 Minoru Kumakura
- 👤 Hidenari Suyama
- 👤 Nobuo Kameda
- 👤 Hideo Kouyama
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 03:51
CPC Classifications
C; C08; C08F; C08F2/00; C08F2/46; G; G02; G02B; G02B1/00; G02B1/04; G02B1/041; G02B1/043
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
75 words
Process for preparing base material of soft contact lens characterized in that water is added to one or more kinds of hydrophilic monomer which can be supercooled or a mixture of said hydrophilic monomer and other monomer, subjecting the mixture to polymerization or copolymerization by ionizing radiation while keeping said monomer(s) and water in supercooled transparent state, said water being added in an amount of 0.1 to 4.8% based on the total quantity of monomers.
Claim 2
Dependent Claim
75 words
Process for preparing base material of soft contact lens characterized in that water is added to one or more kinds of hydrophilic monomer which can be supercooled or a mixture of said hydrophilic monomer and other monomer, subjecting the mixture to polymerization or copolymerization by ionizing radiation while keeping said monomer(s) and water in supercooled transparent state, said water being added in an amount of 0.1 to 4.8% based on the total quantity of monomers.
Claim 3
Dependent Claim
32 words
Process for preparing base material of soft contact lens as defined in claim (1), wherein said hydrophilic monomer which can be supercooled is ester compound of polyalcohol and acrylic or methacrylic acid.
Claim 4
Dependent Claim
48 words
Process for preparing base material of soft contact lens as defined in claim (2), wherein said ester compound is selected from a group consisting of hydroxyethylacrylate, hydroxyethylmethacrylate, hydroxypropylacrylate, hydroxypropylmethacrylate, polyehtylene glycol acrylate, polyethylene glycol methacrylate, polyethylene glycol diacrylate, polyethylene glycol dimethacrylate, methoxypolyethylene glycol acrylate, and methoxypolyethylene glycol methacrylate.
Claim 5
Dependent Claim
33 words
Process for preparing base material of soft contact lens as defined in claim (1), wherein polymerization by ionizing radiation takes place at a temperature within a range from -100° C. to 0° C.
Claim 6
Dependent Claim
76 words
Process for preparing base material of soft contact lens characterized in that water is added to one or more kinds of hydrophilic monomer which can be supercooled or a mixture of said hydrophilic monomer and other monomer, subjecting the mixture to polymerization or copolymerization by ionizing radiation while keeping said monomer(s) and water in a supercooled transparent state, said water being added in an amount of 0.1 to 3.0% based on the total quantity of monomers.
Claim 7
Dependent Claim
76 words
Process for preparing base material of soft contact lens characterized in that water is added to one or more kinds of hydrophilic monomer which can be supercooled or a mixture of said hydrophilic monomer and other monomer, subjecting the mixture to polymerization or copolymerization by ionizing radiation while keeping said monomer(s) and water in a supercooled transparent state, said water being added in an amount of 0.1 to 3.0% based on the total quantity of monomers.
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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) | 1993-02-26 | 1993-08-28 | 1994-02-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-02-26 | 1997-08-28 | 1998-02-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-02-26 | 2001-08-28 | 2002-02-27 | $7700.00 | Window Closed / Lapsed |