Patent US4940628A successfully refreshed from Google Patents.
US4940628A
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Erasable system including marking surface and erasable ink composition
Assignee: Berol Corp
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Filing: 1988-10-24
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Granted: 1990-07-10
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Expires: 2008-10-24
Abstract
Abstract An erasable system including a marking element providing a substantially non-porous marking surface and an erasable marking composition for applying markings to the marking surface. The erasable marking composition comprises a dispersion of a particulate film-forming polymeric material and a colorant and preferably also include a water soluble polymer.
Inventors
- 👤 Nan J. Lin
- 👤 Peter G. Hanley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 19:11
CPC Classifications
B; B41; B41M; B41M5/00; B41M5/0029; Y; Y10; Y10S; Y10S260/00; Y10S260/38; Y10T; Y10T428/00; Y10T428/24; Y10T428/24802; Y10T428/24893; Y10T428/24901; Y10T428/25; Y10T428/254; Y10T428/31504; Y10T428/31844; Y10T428/31848; Y10T428/31855; Y10T428/31909; Y10T428/31924; Y10T428/31928
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
140 words
An erasable system including a marking element and an erasable marking composition for applying markings to the marking element, said marking element comprising a plurality of superposed sheets bound in the form of a book, each sheet comprising a non-porous marking surface comprising a polymeric material carried by a substrate, said marking composition consisting essentially of an aqueous dispersion of a particulate, polymeric film-forming material, a colorant, and an amount of a polymeric shear-thinning material sufficient to provide an erasable marking composition having a shear-thinning index between about 0.01 to about 0.6, said marking composition having a viscosity of about 100 cPs or lower when measured at a shear rate of 300 reciprocal seconds and providing a coalesced residue on drying which is substantially water insoluble and which can be completely erased from the marking surface with an elastomeric eraser.
Claim 2
Dependent Claim
140 words
An erasable system including a marking element and an erasable marking composition for applying markings to the marking element, said marking element comprising a plurality of superposed sheets bound in the form of a book, each sheet comprising a non-porous marking surface comprising a polymeric material carried by a substrate, said marking composition consisting essentially of an aqueous dispersion of a particulate, polymeric film-forming material, a colorant, and an amount of a polymeric shear-thinning material sufficient to provide an erasable marking composition having a shear-thinning index between about 0.01 to about 0.6, said marking composition having a viscosity of about 100 cPs or lower when measured at a shear rate of 300 reciprocal seconds and providing a coalesced residue on drying which is substantially water insoluble and which can be completely erased from the marking surface with an elastomeric eraser.
Claim 3
Dependent Claim
31 words
A system of claim 1 where the substantially non-porous surfaces is provided by a polymeric material selected from the group consisting of cellulosics, polyesters, polyethylenes, polypropylenes, polystyrenes, or mixtures of these.
Claim 4
Dependent Claim
19 words
A system of claim 1 where the marking element comprises a layer of polymeric material carried by a substrate.
Claim 5
Dependent Claim
19 words
A system of claim 3 where the thickness of the layer is between about 0.1 to about 10 mils.
Claim 6
Dependent Claim
10 words
A system of claim 4 where the substrate is paper.
Claim 7
Dependent Claim
18 words
A system of claim 5 where the paper has a thickness between about 1 to about 100 mils.
Claim 8
Dependent Claim
27 words
A system of claim 6 where the layer of polymeric material is selected from the group consisting of cellulosics, polyesters, polyethylenes, polypropylenes, polystyrenes, or mixtures of these.
Claim 9
Dependent Claim
40 words
A system of claim 1 where the polymeric film forming material is selected from the group consisting of a conjugated diene-containing polymeric material, a styrene-containing polymeric material, an acrylonitrile-containing polymeric material, a carboxylated acrylonitrile-containing polymeric material and mixtures of these.
Claim 10
Dependent Claim
35 words
A system of claim 1 where the amount of film forming polymeric material in the marking composition is between about 1 to about 70 percent by weight based on the total weight of the composition.
Claim 11
Dependent Claim
23 words
A system of claim 9 where the amount of film forming polymeric material is between about 3 to about 40 percent by weight.
Claim 12
Dependent Claim
20 words
A system of claim 10 where the amount of colorant is between about 0.3 to about 15 percent by weight.
Claim 13
Dependent Claim
27 words
A system of claim 1 where the viscosity of the marking composition is between about 1 cPs to about 70 cPs when measured at 300 reciprocal seconds.
Claim 14
Dependent Claim
34 words
A system of claim 1 where the marking composition includes a polymeric shear-thinning material selected from the group consisting of xanthan gum, carageenan gum, locust bean gum, hydroxyethylcellulose, guar gum and mixtures of these.
Claim 15
Dependent Claim
33 words
A system of claim 13 where the polymeric shear-thinning material is xanthan gum in an amount between about 0.05 to about 2 percent by weight based on the total weight of the composition.
Claim 16
Dependent Claim
12 words
A system of claim 1 where the colorant is substantially water insoluble.
Claim 17
Dependent Claim
20 words
A system of claim 1 where the colorant can be rendered substantially water insoluble on drying of the marking composition.
Claim 18
Dependent Claim
20 words
A system of claim 1 where the amount of colorant is between about 0.1 to about 40 percent by weight.
Claim 19
Dependent Claim
16 words
A system of claim 1 where the erasable marking composition is retained in a ball-point pen.
Claim 20
Dependent Claim
112 words
A marking element comprising a plurality of superposed sheets bound in the form of a book, each sheet comprising a non-porous marking surface comprising a polymeric material carried by a substrate, at least one of said sheets carrying a marking on the non-porous surface, said marking being completely erasable from the non-porous surface by an elastomeric eraser and said marking being a dry, substantially water insoluble, coalesced residue of a marking composition consisting essentially of an aqueous dispersion of a particulate, polymeric film-forming material, a colorant, and a polymeric shear-thinning material, said marking composition having a viscosity of less than 100 cPs when measured at a shear rate of 300 reciprocal seconds.
Claim 21
Dependent Claim
112 words
A marking element comprising a plurality of superposed sheets bound in the form of a book, each sheet comprising a non-porous marking surface comprising a polymeric material carried by a substrate, at least one of said sheets carrying a marking on the non-porous surface, said marking being completely erasable from the non-porous surface by an elastomeric eraser and said marking being a dry, substantially water insoluble, coalesced residue of a marking composition consisting essentially of an aqueous dispersion of a particulate, polymeric film-forming material, a colorant, and a polymeric shear-thinning material, said marking composition having a viscosity of less than 100 cPs when measured at a shear rate of 300 reciprocal seconds.
Claim 22
Dependent Claim
32 words
A marking element of claim 19 where the substantially non-porous surface is provided by a polymeric material selected from the group consisting of cellulosics, polyesters, polyethylenes, polypropylenes, polystyrenes, or mixtures of these.
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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) | 1993-07-09 | 1994-01-08 | 1994-07-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-07-09 | 1998-01-08 | 1998-07-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-07-09 | 2002-01-08 | 2002-07-10 | $7700.00 | Window Closed / Lapsed |