Patent US5139815A successfully refreshed from Google Patents.
US5139815A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Acid catalyzed silicone release layers
Assignee: Smith H P Paper Co
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Filing: 1990-08-13
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Granted: 1992-08-18
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Expires: 2010-08-13
Abstract
Abstract A release sheet for adhesive products is provided wherein an acidic material such as an acidic polymer is disposed between a substrate layer and an acid catalyzed silicone release layer. The acid catalyzed silicone release layer is preferably a photocationic curable cycloaliphatic epoxy functional poly-dimethyl-siloxane. Provision of the acidic material between the silicone release layer and the substrate prevents neutralization of acids formed during cure of the silicone layer. Thus, faster cure times can be achieved.
Inventors
- 👤 Robert Patterson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 20:46
CPC Classifications
D; D21; D21H; D21H19/00; D21H19/10; D21H19/14; D21H19/24; D21H19/32; C; C09; C09J; C09J7/00; C09J7/40; C09J7/401; C09J7/403; D21H17/00; D21H17/20; D21H17/33; D21H17/46; D21H17/59; D21H25/00; D21H25/04; D21H25/06; C09J2301/00; C09J2301/40; C09J2301/416; C09J2483/00; C09J2483/005
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
72 words
A process for preparing a release sheet, comprising the steps of: providing an acidic material on at least one surface of a substrate layer, wherein the acidic material is provided in an amount sufficient to provide a surface with a pH of about 1 to about 5; applying an acid catalyzed uncured silicone release layer on said acidic material on said surface of said substrate layer; and curing said silicone release layer.
Claim 2
Dependent Claim
72 words
A process for preparing a release sheet, comprising the steps of: providing an acidic material on at least one surface of a substrate layer, wherein the acidic material is provided in an amount sufficient to provide a surface with a pH of about 1 to about 5; applying an acid catalyzed uncured silicone release layer on said acidic material on said surface of said substrate layer; and curing said silicone release layer.
Claim 3
Dependent Claim
15 words
The process of claim 1 wherein said acidic material consists essentially of an acidic polymer.
Claim 4
Dependent Claim
31 words
The process of claim 2, wherein the acidic polymer is selected from the group consisting of polyacrylic acid, ethylene acrylic acid copolymer, ethylene maleic acid copolymer and polyacryloamidomethyl propane sulfonic acid.
Claim 5
Dependent Claim
16 words
The process of claim 1, wherein the acidic material is extrusion coated onto the substrate layer.
Claim 6
Dependent Claim
29 words
The process of claim 1, wherein said silicone release layer is a photocationic curable release layer and curing is initiated by exposing said silicone release layer to UV light.
Claim 7
Dependent Claim
18 words
The process of claim 5, wherein said curing further includes the step of heating said silicone release layer.
Claim 8
Dependent Claim
21 words
The process of claim 1 wherein the acidic material provides a surface with a pH of about 1.5 to about 4.
Claim 9
Dependent Claim
21 words
The process of claim 1, wherein the acidic material provides a surface with a pH of about 1.5 to about 3.
Claim 10
Dependent Claim
18 words
The process of claim 1, wherein the acidic material provides a surface with a pH of about 2.
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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) | 1995-08-18 | 1996-02-17 | 1996-08-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-08-18 | 2000-02-17 | 2000-08-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-08-18 | 2004-02-17 | 2004-08-18 | $7700.00 | Window Closed / Lapsed |