US4935308A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Composite material and method of making same
Assignee: Lockheed Martin Corp
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Filing: 1985-09-12
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Granted: 1990-06-19
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Expires: 2005-09-12
Abstract
Abstract A protective material comprising a layer of vinylidene chloride or saran or copolymer of vinylidene chloride between two layers of polyethylene to provide protection against both permeation and breakthrough. A cloth backing or inner layer can be added to this material for comfort. The material can be modified with a reinforcing material such as fiberglass or scrim cloth. Inclusion of an indicator substance between layers, or impregnated in a layer, provides further protection by warning the user of permeation and breakthrough. This material can be utilized in protective clothing such as gloves, as enclosures for instruments and equipment, as a container, and in other applications. The material is preferably formed by first surface treating one or more layers of polyethylene and/or vinylidene chloride or saran with a solution comprising any hexavalent chromium compound such as a chromate or chromium trioxide in hydrogen ion such as supplied from sulfphuric acid, and then pressing the layers of vinylidene chloride and polyethylene together under heat and pressure such as 330 degrees Fahrenheit at 400 PSI.
Inventors
- 👤 Richard J. Guerra
- 👤 David C. Marshall
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 22:11
CPC Classifications
A; A62; A62D; A62D5/00; A41; A41D; A41D31/00; A41D31/04; A62B; A62B17/00; B; B32; B32B; B32B27/00; B32B27/30; Y; Y10; Y10S; Y10S428/00; Y10S428/911; Y10S428/913; Y10T; Y10T428/00; Y10T428/31504; Y10T428/31855; Y10T428/31909; Y10T428/31913; Y10T428/3192; Y10T428/31928; Y10T442/00; Y10T442/30; Y10T442/3854; Y10T442/387
Claims Analysis
Total Claims: 29
Claim 1
Independent Claim
73 words
A protective material, comprising: a plurality of preformed sheets of a polyolefin; a preformed sheet of a first material, selected from the group consisting of vinylidene chloride homopolymers and copolymers, and any combination thereof, disposed between ones of said layers of said polyolefin and in contact with at least one of said layers of said polyolefin; and indicator means included within said material for indicating the presence of at least one predetermined substance.
Claim 2
Dependent Claim
73 words
A protective material, comprising: a plurality of preformed sheets of a polyolefin; a preformed sheet of a first material, selected from the group consisting of vinylidene chloride homopolymers and copolymers, and any combination thereof, disposed between ones of said layers of said polyolefin and in contact with at least one of said layers of said polyolefin; and indicator means included within said material for indicating the presence of at least one predetermined substance.
Claim 3
Dependent Claim
75 words
A protective material, comprising: a plurality of preformed sheets of a polyolefin; and a preformed sheet of a first material, selected from the group consisting of vinylidene chloride homopolymers and copolymers, and any combination thereof, disposed between ones of said layers of said polyolefin and in contact with at least one of said layers of said polyolefin; wherein said polyolefin has been surface treated with a solution comprising a hexavalent chromium compound and an acid.
Claim 4
Dependent Claim
75 words
A protective material, comprising: a plurality of preformed sheets of a polyolefin; and a preformed sheet of a first material, selected from the group consisting of vinylidene chloride homopolymers and copolymers, and any combination thereof, disposed between ones of said layers of said polyolefin and in contact with at least one of said layers of said polyolefin; wherein said polyolefin has been surface treated with a solution comprising a hexavalent chromium compound and an acid.
Claim 5
Dependent Claim
15 words
A protective material as recited in claim 2 wherein said polyolefin comprises polyethylene or polypropylene.
Claim 6
Dependent Claim
14 words
A protective material as recited in claim 2 wherein said solution further comprises water.
Claim 7
Dependent Claim
31 words
A protective material as recited in claim 4 wherein said preformed sheet of said first material has been surface treated with a solution comprising a hexavalent chromium compound and an acid.
Claim 8
Dependent Claim
15 words
A protective material as recited in claim 4, further comprising means for reinforcing said laminate.
Claim 9
Dependent Claim
17 words
A protective material as recited in claim 2 wherein said polyolefin has been surface treated by oxidation.
Claim 10
Dependent Claim
23 words
A protective material as recited in claim 2 wherein said preformed sheets of a polyolefin are each in the form of a film.
Claim 11
Dependent Claim
46 words
A laminate, comprising a preformed sheet of a first material selected from the group consisting of vinylidene chloride homopolymers and copolymers, and any combination thereof; and a polyolefin laminated to, and in contact with, said material; wherein said polyolefin comprises a sheet of polyethylene or polypropylene.
Claim 12
Dependent Claim
46 words
A laminate, comprising a preformed sheet of a first material selected from the group consisting of vinylidene chloride homopolymers and copolymers, and any combination thereof; and a polyolefin laminated to, and in contact with, said material; wherein said polyolefin comprises a sheet of polyethylene or polypropylene.
Claim 13
Dependent Claim
25 words
A laminate as recited in claim 9 wherein said polyolefin has been surface treated with a solution comprising a hexavalent chromium compound and an acid.
Claim 14
Dependent Claim
13 words
A laminate as recited in claim 10 wherein said solution further comprises water.
Claim 15
Dependent Claim
26 words
A laminate as recited in claim 9 wherein said first material has been surface treated with a solution comprising a hexavalent chromium compound and an acid.
Claim 16
Dependent Claim
25 words
A laminate as recited in claim 9, further comprising indicator means included in said laminate for indicating the presence of at least one predetermined substance.
Claim 17
Dependent Claim
14 words
A laminate as recited in claim 9 further comprising means for reinforcing said laminate.
Claim 18
Dependent Claim
17 words
A laminate as recited in claim 9 wherein said preformed sheet has been surface treated by oxidation.
Claim 19
Dependent Claim
16 words
A laminate as recited in claim 15 wherein said polyolefin has been surface treated by oxidation.
Claim 20
Dependent Claim
16 words
A laminate as recited in claim 9 wherein said polyolefin has been surface treated by oxidation.
Claim 21
Dependent Claim
17 words
A laminate as recited in claim 9 wherein said polyolefin is in the form of a film.
Claim 22
Dependent Claim
67 words
A protective material, comprising a plurality of preformed sheets of a polyolefin; and a preformed sheet of a first material, selected from the group consisting of vinylidene chloride homopolymers and copolymers, and any combination thereof, disposed between ones of said layers of said polyolefin and in contact with at least one of said layers of said polyolefin; wherein said preformed sheet has been surface treated by oxidation.
Claim 23
Dependent Claim
67 words
A protective material, comprising a plurality of preformed sheets of a polyolefin; and a preformed sheet of a first material, selected from the group consisting of vinylidene chloride homopolymers and copolymers, and any combination thereof, disposed between ones of said layers of said polyolefin and in contact with at least one of said layers of said polyolefin; wherein said preformed sheet has been surface treated by oxidation.
Claim 24
Dependent Claim
17 words
A protective material as recited in claim 19 wherein said polyolefin has been surfaced treated by oxidation.
Claim 25
Dependent Claim
22 words
Protective apparel as recited in claim 19 wherein at least one surface of one of said layers of polyolefin has been oxidized.
Claim 26
Dependent Claim
33 words
Protective apparel as recited in claim 21 wherein at least one surface of said layer selected from the group consisting of vinylidene chloride homopolymers and copolymers, and any combination thereof has been oxidized.
Claim 27
Dependent Claim
33 words
Protective apparel as recited in claim 19 wherein at least one surface of said layer selected from the group consisting of vinylidene chloride homopolymers and copolymers, and any combination thereof has been oxidized.
Claim 28
Dependent Claim
36 words
Protective apparel as recited in claim 19 wherein said preformed sheet is selected from the group consisting of vinylidene chloride homopolymers and copolymers, and any combination thereof is in contact with a said layer of polyolefin.
Claim 29
Dependent Claim
21 words
Protective apparel as recited in claim 19 wherein said preformed sheets of polyolefin are each in the form of a film.
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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) | 1993-06-18 | 1993-12-18 | 1994-06-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-06-18 | 1997-12-18 | 1998-06-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-06-18 | 2001-12-18 | 2002-06-19 | $7700.00 | Window Closed / Lapsed |