US4045238A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Regenerated cellulose sponge
Assignee: MedChem Products Inc
•
Filing: 1975-12-04
•
Granted: 1977-08-30
•
Expires: 1995-12-04
Abstract
Abstract Regenerated cellulose sponges of incresed absorbency and rate of absorption formed by impregnating the sponge material with a solution or dispersion containing from 0.005 to 0.25% of a water-soluble or water-dispersible, high molecular weight, hydrophylic, film-forming polymer, drying the impregnated sponge and compressing it. The presence of the film-forming polymer allows the cutting of desired shaped individual sponges from the treated sponge material with a minimal formation of lint particles on the cut surfaces.
Inventors
- 👤 Orlando A. Battista
- 👤 Richard L. Ward
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 09:43
CPC Classifications
C; C08; C08J; C08J9/00; C08J9/36; C08J9/40; C08J9/42; A; A61; A61L; A61L15/00; A61L15/16; A61L15/22; A61L15/28; A61L15/32; A61L15/325; A61L15/42; A61L15/425; C08J2301/00; C08J2401/00; C08J2489/00
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
113 words
A method for increasing the liquid absorbency of regenerated cellulose sponge which comprises immersing the sponge, free of water-soluble materials, in a solution or dispersion consisting of water and a water-soluble or water-dispersible, high molecular weight, hydrophylic, film-forming polymer, the solution or dispersion containing from about 0.005 to about 0.250% by weight of the polymer, compressing and releasing the sponge while so immersed so as to impregnate the sponge with and distribute uniformly throughout the sponge the film-forming polymer, drying the impregnated sponge to a volatiles content including water of not more than about 0.5%, conditioning the dried sponge to a moisture content of at least about 6% and compressing the conditioned sponge.
Claim 2
Independent Claim
113 words
A method for increasing the liquid absorbency of regenerated cellulose sponge which comprises immersing the sponge, free of water-soluble materials, in a solution or dispersion consisting of water and a water-soluble or water-dispersible, high molecular weight, hydrophylic, film-forming polymer, the solution or dispersion containing from about 0.005 to about 0.250% by weight of the polymer, compressing and releasing the sponge while so immersed so as to impregnate the sponge with and distribute uniformly throughout the sponge the film-forming polymer, drying the impregnated sponge to a volatiles content including water of not more than about 0.5%, conditioning the dried sponge to a moisture content of at least about 6% and compressing the conditioned sponge.
Claim 3
Dependent Claim
24 words
A method as defined in claim 1 wherein the sponge is conditioned to a moisture content of from 7 to 12% prior to compression.
Claim 4
Dependent Claim
25 words
A method as defined in claim 2 wherein the conditioned sponge is compressed to a bulk density of between about 7 lbs./cu.ft. and 50 lbs./cu.ft.
Claim 5
Dependent Claim
23 words
A method as defined in claim 2 wherein the solution or dispersion contains from 0.010 to 0.030% by weight of the film-forming polymer.
Claim 6
Dependent Claim
25 words
A method as defined in claim 4 wherein the conditioned sponge is compressed to a bulk density of between about 20 lbs./cu.ft. and 50 lbs./cu.ft.
Claim 7
Dependent Claim
14 words
A method as defined in claim 1 wherein the film-forming polymer is microcrystalline collagen.
Claim 8
Dependent Claim
13 words
A method as defined in claim 1 wherein the film-forming polymer is gelatin.
Claim 9
Dependent Claim
14 words
A method as defined in claim 1 wherein the film-forming polymer is regenerated cellulose.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-08-29 | 1981-02-28 | 1981-08-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-08-29 | 1985-02-28 | 1985-08-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-08-29 | 1989-02-28 | 1989-08-30 | $7700.00 | Window Closed / Lapsed |