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US4422984A Expired / Lapsed US ⏱️ 0.0 years remaining

Centrifugal casting of contact lenses

Assignee: Sunsoft Corp
•
Filing: 1982-09-13
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Granted: 1983-12-27
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Expires: 2002-09-13
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Abstract

Abstract A method of casting contact lenses by forcing the liquid monomer into the optical molds under very high pressure, the pressure being provided by centrifugal force by revolving the lens mold around a center of rotation perpendicular to the optical axis of the lens and polymerizing the liquid monomer under pressure to form the lens.

Inventors

  • 👤 Charles W. Neefe

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 20:16
CPC Classifications
B; B29; B29D; B29D11/00; B29D11/00009; B29D11/0048; B29D11/00519; B29C; B29C39/00; B29C39/003; B29C39/006; B29C39/02; B29C39/04; B29C39/08; B29C41/00; B29C41/02; B29C41/04; B29D11/00038; B29D11/00115; B29K; B29K2033/00; B29K2033/04; B29L; B29L2011/00; B29L2011/0016; B29L2011/0041; B29L2031/00; B29L2031/76; Y; Y10; Y10S; Y10S425/00; Y10S425/808

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 135 words
A method of centrifugal casting optical lenses by the steps of, placing a selected liquid lens monomer between an inner mold and an outer mold, revolving a plurality of these lens molds around a common center with the lens optical axis passing through the common center of rotation, allowing the liquid lens monomer to begin polymerization and the liquid monomer viscosity to increase to form a syrup, adding rotational power to increase the speed of rotation of the lens molds around their common center and allowing the polymerization to proceed and the volume of lens monomer to decrease and the speed of rotation of the lens molds to increase until a solid resinous lens fills the space between the lens molds allowing the rotation to cease and removing the finished lens from the lens molds.
Claim 2
Independent Claim 135 words
A method of centrifugal casting optical lenses by the steps of, placing a selected liquid lens monomer between an inner mold and an outer mold, revolving a plurality of these lens molds around a common center with the lens optical axis passing through the common center of rotation, allowing the liquid lens monomer to begin polymerization and the liquid monomer viscosity to increase to form a syrup, adding rotational power to increase the speed of rotation of the lens molds around their common center and allowing the polymerization to proceed and the volume of lens monomer to decrease and the speed of rotation of the lens molds to increase until a solid resinous lens fills the space between the lens molds allowing the rotation to cease and removing the finished lens from the lens molds.
Claim 3
Dependent Claim 18 words
A method as in claim 1 wherein the inner mold is convex and the outer mold is concave.
Claim 4
Dependent Claim 12 words
A method as in claim 1 wherein the outer mold is convex.
Claim 5
Dependent Claim 21 words
A method as in claim 1 wherein the inner mold is metal and the outer mold is of a resinous material.
Claim 6
Dependent Claim 17 words
A method as in claim 1 wherein the inner and outer mold is of a resinous material.
Claim 7
Dependent Claim 23 words
A method as in claim 1 wherein the liquid monomer is added through an opening provided in the center of the rotational shift.
Claim 8
Dependent Claim 22 words
A method as in claim 1 wherein heat is applied to the lens mold to reduce the time required to achieve polymerization.
Claim 9
Dependent Claim 16 words
A method as in claim 1 wherein one or more of the molds surface is toric.
Claim 10
Dependent Claim 16 words
A method as in claim 1 wherein one or more of the molds surface is aspheric.
Claim 11
Dependent Claim 14 words
A method as in claim 1 wherein the lens produced is a bifocal lens.

References Cited (Backward Citations)

US2325019A Cited
US2429692A Cited
US3010153A Cited
US3660545A Cited
US3274301A Cited
US4217124A Cited
US4002418A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1986-12-26 1987-06-27 1987-12-27 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1990-12-26 1991-06-27 1991-12-27 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1994-12-26 1995-06-27 1995-12-27 $7700.00 Window Closed / Lapsed

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