US4234637A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Microporous protective coverings
Assignee: Department of National Defence
•
Filing: 1979-06-20
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Granted: 1980-11-18
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Expires: 1999-06-20
Abstract
Abstract A flexible, microporous, non-water soluble, non-skin-toxic film is provided for use in protective garments such as diver's suits, foul weather suits and the like. The film is of a thickness in the range of about 12.5μ to 12.5 mm and possesses about 100 to 1000 pores of a diameter in the range of about 2 to 100μ per cm 2 of film surface. The porosity of the film permits the passage of body vapors but prevents, at least up to modest external pressures, the counter-passage of water. The film can be of a foamed material to provide increased insulational value.
Inventors
- 👤 Richard B. H. Sewell
- 👤 Derek J. Kidd
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 06:53
CPC Classifications
A; A41; A41D; A41D31/00; A41D31/04; A41D31/18; Y; Y10; Y10T; Y10T156/00; Y10T156/10; Y10T156/1052; Y10T156/1056; Y10T428/00; Y10T428/24; Y10T428/24273; Y10T428/24298; Y10T428/26; Y10T428/268; Y10T428/269
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
119 words
A flexible, microporous non-water-soluble, non-skin-toxic film of a material selected from the group consisting of natural and synthetic elastomers and synthetic polymers for use in protective garments, said film having first and second surfaces, a thickness between said surfaces being in the range of about 12.5μ to 12 mm, and between about 100 to 1000 pores per cm 2 of film surface, said pores extending between said surfaces and having a diameter in the range of about 2 to 100μ, wherein the pores are tapered and have an average diameter at the first surface of the film of about 2μ and an average diameter at the second surface of the film in the range of about 30 to 100μ.
Claim 2
Dependent Claim
119 words
A flexible, microporous non-water-soluble, non-skin-toxic film of a material selected from the group consisting of natural and synthetic elastomers and synthetic polymers for use in protective garments, said film having first and second surfaces, a thickness between said surfaces being in the range of about 12.5μ to 12 mm, and between about 100 to 1000 pores per cm 2 of film surface, said pores extending between said surfaces and having a diameter in the range of about 2 to 100μ, wherein the pores are tapered and have an average diameter at the first surface of the film of about 2μ and an average diameter at the second surface of the film in the range of about 30 to 100μ.
Claim 3
Dependent Claim
14 words
A microporous film according to claim 1, wherein the film is of foamed material.
References Cited (Backward Citations)
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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) | 1983-11-18 | 1984-05-19 | 1984-11-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-11-18 | 1988-05-19 | 1988-11-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-11-18 | 1992-05-19 | 1992-11-18 | $7700.00 | Window Closed / Lapsed |