US3721657A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hydrophilic gel polymers of vinylpyrrolidine and hydroxyalkyl methacrylate
Assignee: Individual
•
Filing: 1970-11-23
•
Granted: 1973-03-20
•
Expires: 1990-11-23
Abstract
Abstract A plastic or resin product obtained by mixing a comminuted pyrrolidone such as polyvinylpyrrolidone, and optionally modifiers and additives such as organic methacrylates, and optionally crosslinking agents, and optionally catalysts, and causing polymerization to take place by elevating the temperature. The inventive product is insoluble in water but is hydratable with water, depending upon proportions of above mentioned components, and may take up in its structure as little as 5 percent by weight of water to as high as 90 percent by weight of water. The inventive hydrated product is optionally transparent, translucent, or opaque, and produced in any shape or size, depending only on the mold in which it is cast. The transparent product is especially suitable for contact lenses. The translucent and opaque products may be fabricated into membranes with pore sizes that can be made selectively, or cast into useful shapes and for other uses.
Inventors
- 👤 M Seiderman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 15:37
CPC Classifications
G; G02; G02B; G02B1/00; G02B1/04; G02B1/041; G02B1/043; C; C08; C08F; C08F220/00; C08F220/02; C08F220/10; C08F220/12; C08F220/20; C08F26/00; C08F26/06; C08F271/00; C08F271/02
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
38 words
The process of claim 1 wherein the catalyst is present and is selected from the group consisting of benzoyl peroxide, lauryl peroxide, cumene hydroperoxide, dibutyl peroxide, azobisisobutyronitrile, tertiary butyl peroxide, tertiary butyl hydroperoxide, and ammonia plus hydrogen peroxide.
Claim 2
Dependent Claim
15 words
The process of claim 1 wherein the hydroxyalkyl methacrylate is hydroxyethyl methacrylate or hydroxypropyl methacrylate.
Claim 3
Dependent Claim
15 words
The process of claim 2 wherein the hydroxyalkyl methacrylate is hydroxyethyl methacrylate or hydroxypropyl methacrylate.
Claim 4
Dependent Claim
22 words
The process of claim 3 wherein the weight ratio of the hydroxyalkyl methacrylate to the vinyl pyrrolidone is from 60:40 to 99:1.
Claim 5
Dependent Claim
19 words
The process of claim 3 wherein the weight ratio of the hydroxyalkyl methacrylate to the vinylpyrrolidone is about 70:30.
Claim 6
Dependent Claim
27 words
The process of claim 5 wherein the amount of cross-linking agent is from 0.1 to 7 parts by weight for each 100 parts by weight of vinylpyrrolidone.
Claim 7
Dependent Claim
27 words
The process of claim 5 wherein the amount of cross-linking agent is from 1 to 5 parts by weight for each 100 parts by weight of vinylpyrrolidone.
Claim 8
Dependent Claim
18 words
The process of claim 1 wherein the hydroxyalkyl methacrylate is a mixture of hydroxyethyl methacrylate and hydroxypropyl methacrylate.
Claim 9
Dependent Claim
23 words
The process of claim 1 wherein the hydroxyalkyl methacrylate is hydroxyethyl methacrylate or hydroxypropyl methacrylate and no cross-linking agent or catalyst is present.
Claim 10
Dependent Claim
128 words
A substantially water insoluble resin obtained by mixing together essentially only vinylpyrrolidone and a hydroxyalkyl methacrylate in a weight ration to the vinylpyrrolidone of from 15:85 to about 99:1; from 0 to about 25 parts by weight for each 100 parts of the vinylpyrrolidone of a cross-linking agent selected from the group consisting of ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, 1,4-butylene glycol dimethacrylate, 1,3-butylene glycol dimethacrylate, and methylacrylic acid with N-methylolacrylamide; and an amount of catalyst ranging from zero to about 5 grams thereof for each 100 grams of reaction mixture; and thereafter heating the mixture thus formed to a temperature of at least about 50*C and maintaining the reaction mixture at such temperature until polymerization is substantially completed.
Claim 11
Dependent Claim
38 words
The resin of claim 11 wherein the catalyst is present and is selected from the group consisting of benzoyl peroxide, lauryl peroxide, cumene hydroperoxide, dibutyl peroxide, azobisisobutyronitrile, tertiary butyl peroxide, tertiary butyl hydroperoxide, and ammonia plus hydrogen peroxide.
Claim 12
Dependent Claim
15 words
The resin of claim 11 wherein the hydroxyalkyl methacrylate is hydroxyethyl methacrylate or hydroxypropyl methacrylate.
Claim 13
Dependent Claim
15 words
The resin of claim 12 wherein the hydroxyalkyl methacrylate is hydroxyethyl methacrylate or hydroxypropyl methacrylate.
Claim 14
Dependent Claim
21 words
The resin of claim 13 wherein the weight ratio of the hydroxyalkyl methacrylate to the vinylpyrrolidone is from 60:40 to 99:1.
Claim 15
Dependent Claim
19 words
The resin of claim 13 wherein the weight ratio of the hydroxyalkyl methacrylate to the vinylpyrrolidone is about 70:30.
Claim 16
Dependent Claim
27 words
The resin of claim 15 wherein the amount of cross-linking agent is from 0.1 to 7 parts by weight for each 100 parts by weight of vinylpyrrolidone.
Claim 17
Dependent Claim
27 words
The resin of claim 15 wherein the amount of cross-linking agent is from 1 to 5 parts by weight for each 100 parts by weight of vinylpyrrolidone.
Claim 18
Dependent Claim
18 words
The resin of claim 11 wherein the hydroxyalkyl methacrylate is a mixture of hydroxyethyl methacrylate and hydroxypropyl methacrylate.
Claim 19
Dependent Claim
23 words
The resin of claim 11 wherein the hydroxyalkyl methacrylate is hydroxyethyl methacrylate or hydroxypropyl methacrylate and no cross-linking agent or catalyst is present.
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) | 1976-03-19 | 1976-09-18 | 1977-03-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-03-19 | 1980-09-18 | 1981-03-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-03-19 | 1984-09-18 | 1985-03-20 | $7700.00 | Window Closed / Lapsed |