US4131696A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Contact lens treatment
Assignee: Burton Parsons and Co Inc
•
Filing: 1977-10-19
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Granted: 1978-12-26
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Expires: 1997-10-19
Abstract
Abstract Hard type contact lenses, such as those made of poly methyl methacrylate, are treated with an aqueous colloidal suspension of a physiologically inert inorganic hydrous oxide to render the lens surfaces wettable by lacrimal fluids thus decreasing eye irritation and increasing wearing comfort.
Inventors
- 👤 William Covington
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 15:30
CPC Classifications
B; B29; B29D; B29D11/00; C; C08; C08J; C08J7/00; C08J7/04; C08J7/043; C08J7/06
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
57 words
A method for increasing the wearing comfort of hard contact lenses which comprises contacting the lens surfaces with an aqueous colloidal suspension of a physiologically inert inorganic hydrous oxide thereby rendering said lens surfaces wettable by lacrimal fluids, rinsing the lenses to remove any non-adhering colloidal particles and inserting the lenses over the cornea of the eye.
Claim 2
Independent Claim
57 words
A method for increasing the wearing comfort of hard contact lenses which comprises contacting the lens surfaces with an aqueous colloidal suspension of a physiologically inert inorganic hydrous oxide thereby rendering said lens surfaces wettable by lacrimal fluids, rinsing the lenses to remove any non-adhering colloidal particles and inserting the lenses over the cornea of the eye.
Claim 3
Dependent Claim
16 words
The method of claim 1 wherein said hard contact lenses are made from poly methyl methacrylate.
Claim 4
Dependent Claim
26 words
The method of claim 2 wherein said inorganic hydrous oxide is selected from the group consisting of the hydrous oxides of tin, silicon, aluminum and magnesium.
Claim 5
Dependent Claim
21 words
The method of claim 3 wherein the inorganic hydrous oxide is produced by the hydrolysis of a salt in aqueous solution.
Claim 6
Dependent Claim
11 words
The method of claim 4 wherein the salt is a chloride.
Claim 7
Dependent Claim
20 words
The method of claim 5 wherein sodium hydroxide is used to adjust the pH of the salt solution during hydrolysis.
Claim 8
Dependent Claim
52 words
In the process of fitting hard type contact lenses to a new wearer, the improvement which comprises treating the lenses prior to insertion in the eye with an aqueous, colloidal suspension of a physiologically inert hydrous inorganic oxide for a time sufficient to render the lens surfaces readily wettable by lacrimal fluids.
Claim 9
Dependent Claim
52 words
In the process of fitting hard type contact lenses to a new wearer, the improvement which comprises treating the lenses prior to insertion in the eye with an aqueous, colloidal suspension of a physiologically inert hydrous inorganic oxide for a time sufficient to render the lens surfaces readily wettable by lacrimal fluids.
Claim 10
Dependent Claim
16 words
The process of claim 7 wherein said hard contact lenses are made from poly methyl methacrylate.
Claim 11
Dependent Claim
25 words
The process of claim 8 wherein said inorganic oxide is selected from the group consisting of the hydrous oxides of tin, silicon, aluminum and magnesium.
References Cited (Backward Citations)
US3549747A
Cited
US3657003A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-12-25 | 1982-06-26 | 1982-12-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-12-25 | 1986-06-26 | 1986-12-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-12-25 | 1990-06-26 | 1990-12-26 | $7700.00 | Window Closed / Lapsed |