Patent US4767653A successfully refreshed from Google Patents.
US4767653A
Expired / Lapsed
US
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Spliceable sheet material
Assignee: 3M Co
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Filing: 1985-11-12
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Granted: 1988-08-30
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Expires: 2005-11-12
Abstract
Abstract Heat-sealable sheet material for use in the fabrication of lapped-seam membrane. In a presently preferred construction, linear low density polyethylene film is adhered to one lateral border of cured polymerized EPDM composition; preferably the adhesive is protected with a removable liner, e.g., a polyester film until lapped-seam splicing is to be carried out. A transfer tape based on thermoplastic heat-sealable adhesive carried by a strippable liner also constitute part of the invention. The transfer tape is advantageously applied to a sheet of uncured EPDM compound and the resultant assembly subjected to heat and pressure to cure the compound and bond the heat-sealable adhesive firmly thereto.
Inventors
- 👤 Richard L. Renstrom
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 17:45
CPC Classifications
E; E04; E04D; E04D5/00; E04D5/12; Y; Y10; Y10T; Y10T428/00; Y10T428/14; Y10T428/1452; Y10T428/19; Y10T428/24; Y10T428/24777; Y10T428/24793; Y10T428/24802; Y10T428/24843; Y10T428/26; Y10T428/263; Y10T428/28; Y10T428/2813; Y10T428/2817; Y10T428/2826; Y10T428/2852; Y10T428/2878; Y10T428/31504; Y10T428/31855; Y10T428/31909; Y10T428/31913; Y10T428/31917; Y10T428/31924; Y10T428/31928; Y10T428/31935
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
187 words
A spliceable sheet material for use in the fabrication of lapped-seam membrane roofing, comprising in combination: a rubbery water-impermeable membrane consisting essentially of thermoset olefin polymer, said membrane having on one side, in a border area along one edge, a thin layer of firmly bonded heat-sealable high molecular weight, thermoplastic adhesive that wets the thermoset olefin polyolefin polymer and that has a softening point of at least about 80° C. and less than about 250° C., said heat-sealable adhesive having a melt index of at least 0.5, said membrane also having on the opposite side in a border area along the opposite edge, a thin layer of the same adhesive, whereby when splicing is effected by overlapping adjacent strips of said sheet material so that the adhesive-coated surfaces are in contact and heat and pressure is applied to the overlapped area, the T-peel values of the spliced borders are at least 17.5 N/cm, the dynamic shear is at least 17.5 N/cm, the static shear is at least 24 hours, and the low temperature flexibility requirements are satisfactory, all as measured in accordance with the tests described herein.
Claim 2
Dependent Claim
187 words
A spliceable sheet material for use in the fabrication of lapped-seam membrane roofing, comprising in combination: a rubbery water-impermeable membrane consisting essentially of thermoset olefin polymer, said membrane having on one side, in a border area along one edge, a thin layer of firmly bonded heat-sealable high molecular weight, thermoplastic adhesive that wets the thermoset olefin polyolefin polymer and that has a softening point of at least about 80° C. and less than about 250° C., said heat-sealable adhesive having a melt index of at least 0.5, said membrane also having on the opposite side in a border area along the opposite edge, a thin layer of the same adhesive, whereby when splicing is effected by overlapping adjacent strips of said sheet material so that the adhesive-coated surfaces are in contact and heat and pressure is applied to the overlapped area, the T-peel values of the spliced borders are at least 17.5 N/cm, the dynamic shear is at least 17.5 N/cm, the static shear is at least 24 hours, and the low temperature flexibility requirements are satisfactory, all as measured in accordance with the tests described herein.
Claim 3
Dependent Claim
19 words
The sheet material of claim 1 wherein the heat-sealable adhesive has a softening point of at least 100° C.
Claim 4
Dependent Claim
25 words
The sheet material of claim 1 wherein the heat-sealable adhesive has a softening point of at least 120° C. but not more than 250° C.
Claim 5
Dependent Claim
20 words
The sheet material of claim 3 wherein the olefin polymer consists essentially of polymerized ethylene, propylene, and diene monomers (EPDM).
Claim 6
Dependent Claim
22 words
The sheet material of claim 4 wherein the heat-sealable adhesive is linear low density polyethylene having a melt index of about 1.0.
Claim 7
Dependent Claim
17 words
The sheet material of claim 1 wherein the heat-sealable adhesive is protectively covered by a strippable liner.
Claim 8
Dependent Claim
54 words
A spliced membrane made by overlapping the adjacent borders of two laterally juxtaposed strips of the sheet material of claim 1, so that the adhesive is interposed between the two thermoset olefin adhesive-coated surfaces are in contact with each other, and applying sufficient heat and pressure to bond the overlapped borders to each other.
Claim 9
Dependent Claim
15 words
The spliced membrane of claim 7 wherein the softening point is at least 120° C.
Claim 10
Dependent Claim
17 words
The sheet material of claim 1 wherein the layer of heat-sealable adhesive is about 90 micrometers thick.
References Cited (Backward Citations)
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Cited
GB1382826A
Cited
EP0048003A1
Cited
US4404249A
Cited
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Cited
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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) | 1991-08-30 | 1992-02-29 | 1992-08-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-08-30 | 1996-02-29 | 1996-08-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-08-30 | 2000-02-29 | 2000-08-30 | $7700.00 | Window Closed / Lapsed |