US4895746A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Stack of pressure sensitive adhesive coated sheets
Assignee: 3M Co
•
Filing: 1989-03-01
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Granted: 1990-01-23
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Expires: 2009-03-01
Abstract
Abstract A stack of aligned sheets, each of which sheets includes a backing, a coating of pressure sensitive adhesive on a lower surface of the backing by which the sheet is adhered to the sheet beneath it in the stack, which coating extends along and within at least 12.5 mm of all of the edges of the backing, release means providing a first adhesion zone between adjacent sheets in the stack and adjacent one of the edges of the sheet for providing a sufficiently low release force between the adhesive coating and the upper surface of the adjacent sheet in the stack to afford, when the sheet is the uppermost sheet in the stack, each initiation of peeling of the sheet from the adjacent sheet in the stack, and attachment means providing a second adhesion zone between adjacent sheets in the stack for providing a sufficiently high release force that is higher than said low release force in the first adhesion zone to firmly adhere adjacent sheets in the stack together and thereby hold the stack of sheets together during handling, while affording continued peeling away of the uppermost sheet in the stack after initiating of such peeling along the first adhesion zone.
Inventors
- 👤 Timothy A. Mertens
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 19:19
CPC Classifications
G; G09; G09F; G09F3/00; G09F3/02; G09F3/0288; G09F2003/0202; G09F2003/0208; G09F2003/021; G09F2003/023; G09F2003/0247; G09F2003/0255; Y; Y10; Y10T; Y10T428/00; Y10T428/14; Y10T428/1405; Y10T428/24; Y10T428/24777; Y10T428/24793; Y10T428/24802; Y10T428/24851; Y10T428/2486
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
216 words
A stack of aligned sheets, each of which sheets includes a backing having a plurality of edges providing a peripheral edge for the sheet, and upper and lower surfaces, a coating of pressure sensitive adhesive on said lower surface by which the sheet is adhered to the sheet beneath it in the stack, said coating extending along and within at least 12.5 mm of all of said edges, release means providing a first adhesion zone between adjacent sheets in the stack and adjacent one of said edges for providing a sufficiently low release force between said adhesive coating and the upper surface of the adjacent sheet in the stack to afford, when the sheet is the uppermost or lowermost sheet in the stack, easy initiation of peeling of the sheet from the adjacent sheet in the stack along the first adhesion zone, and attachment means providing a second adhesion zone between adjacent sheets in the stack for providing a sufficiently high release force that is higher than said low release force in the first adhesion zone to firmly adhere adjacent sheets in the stack together and thereby hold the stack of sheets together during handling, while affording continued peeling away of the sheet in the stack after initiating of such peeling along the first adhesion zone.
Claim 2
Dependent Claim
216 words
A stack of aligned sheets, each of which sheets includes a backing having a plurality of edges providing a peripheral edge for the sheet, and upper and lower surfaces, a coating of pressure sensitive adhesive on said lower surface by which the sheet is adhered to the sheet beneath it in the stack, said coating extending along and within at least 12.5 mm of all of said edges, release means providing a first adhesion zone between adjacent sheets in the stack and adjacent one of said edges for providing a sufficiently low release force between said adhesive coating and the upper surface of the adjacent sheet in the stack to afford, when the sheet is the uppermost or lowermost sheet in the stack, easy initiation of peeling of the sheet from the adjacent sheet in the stack along the first adhesion zone, and attachment means providing a second adhesion zone between adjacent sheets in the stack for providing a sufficiently high release force that is higher than said low release force in the first adhesion zone to firmly adhere adjacent sheets in the stack together and thereby hold the stack of sheets together during handling, while affording continued peeling away of the sheet in the stack after initiating of such peeling along the first adhesion zone.
Claim 3
Dependent Claim
52 words
A stack of sheets according to claim 1 wherein said release means provides a release force value of less than about 15 grams per inch in said first adhesion zone, and said attachment means provides a release force value of greater than about 20 grams per inch in said second adhesion zone.
Claim 4
Dependent Claim
56 words
A stack of sheets according to claim 2 wherein said release means includes a coating of silicone low adhesion backsize along said upper surface in said first adhesion zone, and said layer of pressure sensitive adhesive is uniform, of the same adhesive composition, and has an adhesion to glass of less than 10 ounces per inch.
Claim 5
Dependent Claim
27 words
A stack of sheets according to claim 3 wherein said coating of pressure sensitive adhesive is a low peel pressure sensitive adhesive containing tacky elastomeric copolymer microspheres.
Claim 6
Dependent Claim
57 words
A stack of sheets according to claim 1 wherein said coating of pressure sensitive adhesive on each of said sheets is a uniform coating of the same pressure sensitive adhesive, and said release means includes a coating of low adhesion backsize coating on the portion of said upper surface of said sheet in said first adhesion zone.
Claim 7
Dependent Claim
37 words
A stack of sheets according to claim 1 wherein said coating of pressure sensitive adhesive is discontinuous on each of said sheets in said first adhesion zone to provide at least a portion of said release means.
Claim 8
Dependent Claim
37 words
A stack of sheets according to claim 1 wherein said coating of pressure sensitive adhesive has a different composition in said first and second adhesion zones to provide at least portions of said release and attachment means.
Claim 9
Dependent Claim
17 words
A stack of sheets according to claim 1 wherein said backing has zones of weakness formed therein.
Claim 10
Dependent Claim
19 words
A stack of sheets according to claim 1 wherein said backing has indicia printed on one of said surfaces.
Claim 11
Dependent Claim
28 words
A stack of sheets according to claim 1 wherein said coating of pressure sensitive adhesive extends along and within at least 6 mm of all of said edges.
Claim 12
Dependent Claim
35 words
A stack of sheets according to claim 1 wherein said coating of pressure sensitive adhesive comprises acrylic acid in one of said adhesion zones and comprises rubber resin in the other of said adhesion zones.
References Cited (Backward Citations)
US2170147A
Cited
US2248317A
Cited
US2574152A
Cited
US2607711A
Cited
US3083393A
Cited
US3373457A
Cited
US3575788A
Cited
US4128954A
Cited
US4107811A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-01-22 | 1993-07-24 | 1994-01-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-01-22 | 1997-07-24 | 1998-01-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-01-22 | 2001-07-24 | 2002-01-23 | $7700.00 | Window Closed / Lapsed |