Patent US3971866A successfully refreshed from Google Patents.
US3971866A
Expired / Lapsed
US
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Thermoformable release liner
Assignee: 3M Co
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Filing: 1974-06-07
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Granted: 1976-07-27
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Expires: 1994-06-07
Abstract
Abstract Thermoformable release liner for use in sheet products subjected to deep-draw thermoforming operations and which may be readily removed as generally one piece by hand-pulling after the thermoforming operation is completed, comprises a multilayer structure including (a) a reinforcing layer of a material that, although it is unsuitable for use as the complete release liner, provides useful properties when used as a thinner layer of the release liner, and (b) at least one additional layer adhered to the reinforcing layer to give body to the release liner.
Inventors
- 👤 Erlin J. Johnson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 13:26
CPC Classifications
C; C09; C09J; C09J7/00; C09J7/20; C09J7/22; C09J7/24; C09J7/241; C09J7/40; C09J7/405; C09J2301/00; C09J2301/30; C09J2301/302; C09J2423/00; C09J2423/04; C09J2423/046; C09J2423/10; C09J2423/106; C09J2477/00; C09J2477/005; C09J2483/00; C09J2483/005; Y; Y10; Y10T; Y10T156/00; Y10T156/10; Y10T156/1002; Y10T156/1036; Y10T156/1038; Y10T428/00; Y10T428/14; Y10T428/1452; Y10T428/1457; Y10T428/24; Y10T428/24628; Y10T428/26; Y10T428/31504; Y10T428/31652; Y10T428/31667; Y10T428/31725; Y10T428/31739; Y10T428/31743; Y10T428/31746
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
187 words
A contoured article comprising a drawn thermoformed base sheet, a layer of pressure-sensitive adhesive united to said base sheet, and a release liner temporarily adhered over substantially the whole area of said layer of adhesive, said liner (1) in its unelongated form requiring less than about 3 pounds per inch width tensile load to exhibit a 10 percent elongation at 325°F and greater than about 3 pounds per inch width tensile load to exhibit a 10 percent elongation at 150°F, (2) comprising (a) a thin thermoplastic reinforcing layer of a first material that, in its unelongated form, requires greater than about 1000 pounds per square inch tensile stress to exhibit a 10 percent elongation at 150°F and can be elongated to at least 200 percent of its original length at 325°F and (b) at least one bodying layer united to the reinforcing layer of a second material that can be elongated to at least 200 percent of its original length at 325°F while remaining as a continuous film adhered to the reinforcing layer, and (3) being removable from the adhesive layer as a continuous sheet by hand-pulling.
Claim 2
Dependent Claim
187 words
A contoured article comprising a drawn thermoformed base sheet, a layer of pressure-sensitive adhesive united to said base sheet, and a release liner temporarily adhered over substantially the whole area of said layer of adhesive, said liner (1) in its unelongated form requiring less than about 3 pounds per inch width tensile load to exhibit a 10 percent elongation at 325°F and greater than about 3 pounds per inch width tensile load to exhibit a 10 percent elongation at 150°F, (2) comprising (a) a thin thermoplastic reinforcing layer of a first material that, in its unelongated form, requires greater than about 1000 pounds per square inch tensile stress to exhibit a 10 percent elongation at 150°F and can be elongated to at least 200 percent of its original length at 325°F and (b) at least one bodying layer united to the reinforcing layer of a second material that can be elongated to at least 200 percent of its original length at 325°F while remaining as a continuous film adhered to the reinforcing layer, and (3) being removable from the adhesive layer as a continuous sheet by hand-pulling.
Claim 3
Dependent Claim
17 words
A contoured article of claim 1 in which the reinforcing layer of the release liner comprises nylon.
Claim 4
Dependent Claim
15 words
A contoured article of claim 1 in which the bodying layer comprises polyethylene or polypropylene.
Claim 5
Dependent Claim
15 words
A contoured article of claim 2 in which the bodying layer comprises polyethylene or polypropylene.
Claim 6
Dependent Claim
19 words
A contoured article of claim 1 in which the reinforcing layer is between 0.1 and 2 mils in thickness.
Claim 7
Dependent Claim
24 words
A contoured article of claim 1 in which the release liner carries a cured polymeric silicone treatment that gives the liner improved release properties.
Claim 8
Dependent Claim
19 words
A contoured article of claim 1 in which the melting point of said second material is less than 325°F.
Claim 9
Dependent Claim
200 words
A contoured article comprising a drawn thermoformed base sheet, a layer of pressure-sensitive adhesive united to said base sheet, and a release liner temporarily adhered over substantially the whole area of said layer of adhesive, said liner (1) in its unelongated form requiring less than about 3 pounds per inch width tensile load to exhibit a 10 percent elongation at 325°F and greater than about 3 pounds per inch width tensile load to exhibit a 10 percent elongation at 150°F, (2) comprising (a) a thermoplastic nylon reinforcing layer that in its unelongated form, requires greater than about 1000 pounds per square inch tensile stress to exhibit a 10 percent elongation at 150°F and can be elongated to at least 200 percent of its original length at 325°F and (b) at least one bodying layer united to the reinforcing layer of a thermoplastic material selected from polyethylene that can be elongated to at least 200 percent of its original length at 325°F while remaining as a continuous film adhered to the reinforcing layer, (3) carrying a cured polymeric silicone treatment that gives the liner improved release properties, and (4) being removable from the adhesive layer as a continuous sheet by hand-pulling.
Claim 10
Dependent Claim
200 words
A contoured article comprising a drawn thermoformed base sheet, a layer of pressure-sensitive adhesive united to said base sheet, and a release liner temporarily adhered over substantially the whole area of said layer of adhesive, said liner (1) in its unelongated form requiring less than about 3 pounds per inch width tensile load to exhibit a 10 percent elongation at 325°F and greater than about 3 pounds per inch width tensile load to exhibit a 10 percent elongation at 150°F, (2) comprising (a) a thermoplastic nylon reinforcing layer that in its unelongated form, requires greater than about 1000 pounds per square inch tensile stress to exhibit a 10 percent elongation at 150°F and can be elongated to at least 200 percent of its original length at 325°F and (b) at least one bodying layer united to the reinforcing layer of a thermoplastic material selected from polyethylene that can be elongated to at least 200 percent of its original length at 325°F while remaining as a continuous film adhered to the reinforcing layer, (3) carrying a cured polymeric silicone treatment that gives the liner improved release properties, and (4) being removable from the adhesive layer as a continuous sheet by hand-pulling.
Claim 11
Dependent Claim
187 words
A multilayered sheet product suitable for deepdraw thermoforming operations comprising a thermoformable base sheet, a layer of pressure-sensitive adhesive united to said base sheet, and a release liner temporarily adhered to said layer of adhesive, said liner (1) in its unelongated form requiring less than about 3 pounds per inch width tensile load to exhibit a 10 percent elongation at 325°F and greater than about 3.0 pounds per inch width tensile load to exhibit a 10 percent elongation at 150°F, (2) comprising (a) a thin thermoplastic reinforcing layer of a first material that, in its unelongated form, requires greater than about 1000 pounds per square inch tensile stress to exhibit a 10 percent elongation at 150°F and can be elongated to at least 200 percent of its original length at 325°F, and (b) at least one bodying layer united to the reinforcing layer of a thermoplastic material that can be elongated to at least 200 percent of its original length at 325°F while remaining as a continuous film adhered to the reinforcing layer, and (3) being removable from the adhesive layer as a continuous sheet by hand-pulling.
Claim 12
Dependent Claim
187 words
A multilayered sheet product suitable for deepdraw thermoforming operations comprising a thermoformable base sheet, a layer of pressure-sensitive adhesive united to said base sheet, and a release liner temporarily adhered to said layer of adhesive, said liner (1) in its unelongated form requiring less than about 3 pounds per inch width tensile load to exhibit a 10 percent elongation at 325°F and greater than about 3.0 pounds per inch width tensile load to exhibit a 10 percent elongation at 150°F, (2) comprising (a) a thin thermoplastic reinforcing layer of a first material that, in its unelongated form, requires greater than about 1000 pounds per square inch tensile stress to exhibit a 10 percent elongation at 150°F and can be elongated to at least 200 percent of its original length at 325°F, and (b) at least one bodying layer united to the reinforcing layer of a thermoplastic material that can be elongated to at least 200 percent of its original length at 325°F while remaining as a continuous film adhered to the reinforcing layer, and (3) being removable from the adhesive layer as a continuous sheet by hand-pulling.
Claim 13
Dependent Claim
17 words
A sheet product of claim 9 in which the reinforcing layer of the release liner comprises nylon.
Claim 14
Dependent Claim
15 words
A sheet product of claim 9 in which the bodying layer comprises polyethylene or polypropylene.
Claim 15
Dependent Claim
15 words
A sheet product of claim 10 in which the bodying layer comprises polyethylene or polypropylene.
Claim 16
Dependent Claim
19 words
A sheet product of claim 9 in which the reinforcing layer is between 0.1 and 2 mils in thickness.
References Cited (Backward Citations)
US3507733A
Cited
US3468744A
Cited
US3452861A
Cited
US3518158A
Cited
US3509991A
Cited
US3565750A
Cited
US3749593A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-07-27 | 1980-01-26 | 1980-07-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-07-27 | 1984-01-26 | 1984-07-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-07-27 | 1988-01-26 | 1988-07-27 | $7700.00 | Window Closed / Lapsed |