Patent US5947918A successfully refreshed from Google Patents.
US5947918A
Expired / Lapsed
US
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Impact energy absorbing composite materials
Assignee: W.L. Gore and Associates Inc
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Filing: 1998-05-04
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Granted: 1999-09-07
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Expires: 2018-05-04
Abstract
Abstract An impact energy absorbing composite material of expanded polytetrafluoroethylene (ePTFE) and an elastomer is disclosed. The composite is comprised of at least one layer of expanded polytetrafluoroethylene and at least one layer of an elastomer. The individual layer thicknesses of the ePTFE and elastomer are controlled to achieve superior high energy impact resistance. The invention herein provides a material having performance that also can be tailored to meet other design needs for a given application, for example, space considerations or comfort.
Inventors
- 👤 Carl H. Jones
- 👤 William B. Johnson
- 👤 John M. Blaha
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 10:16
CPC Classifications
A; A63; A63B; A63B71/00; A63B71/08; A63B71/085; A63B2071/088; Y; Y10; Y10T; Y10T442/00; Y10T442/60; Y10T442/674
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
59 words
An impact energy absorbing article comprising: a) a layer of polytetrafluoroethylene (PTFE) having a PTFE layer thickness and a density less than about 2.0 g/cm 3 , and b) a layer of an elastomer having an elastomer layer thickness, wherein a ratio of said PTFE layer thickness to said elastomer layer thickness is greater than or equal to 0.5.
Claim 2
Dependent Claim
59 words
An impact energy absorbing article comprising: a) a layer of polytetrafluoroethylene (PTFE) having a PTFE layer thickness and a density less than about 2.0 g/cm 3 , and b) a layer of an elastomer having an elastomer layer thickness, wherein a ratio of said PTFE layer thickness to said elastomer layer thickness is greater than or equal to 0.5.
Claim 3
Dependent Claim
15 words
The impact energy absorbing article of claim 1 wherein said ratio is greater than one.
Claim 4
Dependent Claim
15 words
The impact energy absorbing article of claim 1 wherein said ratio is greater than three.
Claim 5
Dependent Claim
15 words
The impact energy absorbing article of claim 1 wherein said ratio is greater than ten.
Claim 6
Dependent Claim
50 words
The impact energy absorbing article of claim 1 wherein said elastomer selected from the group consisting of polyisoprene, cis-1,4 polyisoprene, polybutadiene, halogenated butyl rubber, styrene-butadiene rubber, polyacrylic rubber, butyl rubber, ethylene-propylene rubber, neoprene rubber, hypalon rubber, polysulfide elastomer, silicone, urethane, fluorocarbon rubber, hexafluoropropylene, tetrafluoroethylene, propylene, chlorotrifluoroethylene, polymethylvinyl ether, and thermoplastic.
Claim 7
Dependent Claim
53 words
The impact energy absorbing article of claim 1 wherein said PTFE is expanded PTFE and has a fibril and node structure or remnants thereof as characterized by peaks at about 327° C. and about 380°0 C. in a thermogram of differential scanning calorimetry in the course of a temperature rise of 10° C./min.
Claim 8
Dependent Claim
18 words
The impact energy absorbing article of claim 6 wherein said density is less than 1.5 g/cm 3 .
Claim 9
Dependent Claim
18 words
The impact energy absorbing article of claim 6 wherein said density is less than 1.0 g/cm 3 .
Claim 10
Dependent Claim
18 words
The impact energy absorbing article of claim 6 wherein said density is less than 0.5 g/cm 3 .
Claim 11
Dependent Claim
41 words
The impact energy absorbing article of claim 1 further comprising a plurality of said layers of PTFE and wherein said ratio is of a sum of the ePTFE layer thicknesses of said plurality of PTFE layers to said elastomer layer thickness.
Claim 12
Dependent Claim
41 words
The impact energy absorbing article of claim 1 further comprising a plurality of said layers of elastomer and wherein said ratio is of said PTFE layer thickness to a sum of the elastomer layer thicknesses of said plurality of elastomer layers.
Claim 13
Dependent Claim
58 words
The impact energy absorbing article of claim 1 further comprising a plurality of said layers of PTFE and a plurality of said layers of elastomer, and wherein said ratio is of a sum of the PTFE layer thicknesses of said plurality of PTFE layers to a sum of the elastomer layer thicknesses of said plurality of elastomer layers.
Claim 14
Dependent Claim
14 words
The impact energy absorbing article of claim 1 wherein said article is a mouth-guard.
Claim 15
Dependent Claim
16 words
The impact energy absorbing article of claim 1 wherein said article is an athletic padding material.
Claim 16
Dependent Claim
17 words
The impact energy absorbing article of claim 1 wherein said article is a component of a shoe.
Claim 17
Dependent Claim
15 words
The impact energy absorbing article of claim 1 wherein said article is a prosthetic device.
Claim 18
Dependent Claim
15 words
The impact energy absorbing article of claim 1 wherein said article is a protective helmet.
Claim 19
Dependent Claim
17 words
The impact energy absorbing article of claim 1 wherein said article is padding to protect mechanical equipment.
Claim 20
Dependent Claim
25 words
The impact energy absorbing article of claim 1 wherein said article is a protective material on the interior of an automobile or other moving vehicle.
Claim 21
Dependent Claim
16 words
The impact energy absorbing article of claim 1 wherein said ratio is between 1:1 and 50:1.
Claim 22
Dependent Claim
16 words
The impact energy absorbing article of claim 1 wherein said ratio is between 1:1 and 10:1.
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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) | 2002-09-06 | 2003-03-08 | 2003-09-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-09-06 | 2007-03-08 | 2007-09-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-09-06 | 2011-03-08 | 2011-09-07 | $7700.00 | Window Closed / Lapsed |