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US5151032A
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Magnetophoretic display panel
Assignee: Pilot Corp
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Filing: 1990-07-12
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Granted: 1992-09-29
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Expires: 2010-07-12
Abstract
Abstract A magnetophoretic display panel comprising a plurality of cells that are sandwiched between two substrates and each of which is filled with a liquid dispersion comprising magnetic particles, a dispersion medium, a colorant and, optionally, a thickener. The magnetic particles are such that: (A) at least 90 wt. % of them have a particle size of 10-150 mu m; (B) they have an apparent density of 0.5-1.6 g/cm3; and (C) they have a saturation magnetization of 40-150 emu/g.
Inventors
- 👤 Tatsuya Igawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 19:10
CPC Classifications
B; B43; B43L; B43L1/00; B43L1/008; G; G09; G09F; G09F9/00; G09F9/30; G09F9/37; G09F9/375; G02; G02F; G02F1/00; G02F1/01; G02F1/09; G02F1/094
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
83 words
A magnetophoretic display panel comprising; a pair of substrates, a plurality of cells sandwiched between said substrates, each of said cells filled with a liquid dispersion comprising magnetic particles, a dispersion medium, and a colorant; at least 90 wt % of said magnetic particles have a particle size in the range of 10-150 μm; said magnetic particles have an apparent density in the range of 0.5-1.6 g/cm 3 ; and said magnetic particles have a saturation magnetization in the range of 40-150 emu/g.
Claim 2
Dependent Claim
83 words
A magnetophoretic display panel comprising; a pair of substrates, a plurality of cells sandwiched between said substrates, each of said cells filled with a liquid dispersion comprising magnetic particles, a dispersion medium, and a colorant; at least 90 wt % of said magnetic particles have a particle size in the range of 10-150 μm; said magnetic particles have an apparent density in the range of 0.5-1.6 g/cm 3 ; and said magnetic particles have a saturation magnetization in the range of 40-150 emu/g.
Claim 3
Dependent Claim
23 words
A magnetophoretic display panel according to claim 1 wherein said magnetic particles comprise porous black iron oxide particles produced by reduction with hydrogen.
Claim 4
Dependent Claim
17 words
A magnetophoretic display panel according to claim 1 wherein said magnetic particles are coated with a resin.
Claim 5
Dependent Claim
22 words
A magnetophoretic display panel according to claim 1, wherein said magnetic particles comprise a magnetic material mixed with a resin and pulverized.
Claim 6
Dependent Claim
29 words
A magnetophoretic display panel according to claim 1, wherein said magnetic material is selected from the group consisting of ferrite, γ-hematite, γ-ferrite oxide, barium ferrite and black iron oxide.
Claim 7
Dependent Claim
15 words
A magnetophoretic display panel according to claim 3, wherein said resin comprises a thermoplastic resin.
Claim 8
Dependent Claim
15 words
A magnetophoretic display panel according to claim 3, wherein said resin comprises a thermosetting resin.
Claim 9
Dependent Claim
13 words
A magnetophoretic display panel according to claim 3, wherein said coating is multi-layered.
Claim 10
Dependent Claim
32 words
A magnetophoretic display panel according to claim 8; wherein said multi-layered coating comprises a first resin coating and a second resin coating, and said first resin is different than said second resin.
Claim 11
Dependent Claim
12 words
A magnetophoretic display panel according to claim 1 further comprising a thickener.
Claim 12
Dependent Claim
84 words
A magnetophoretic display panel comprising; a pair of substrates, a plurality of cells between said substrates, each of said cells is filled with a liquid dispersion comprising magnetic particles, a dispersion medium, and a thickener, wherein, at least 90 wt % of said magnetic particles have a particle size in the range of 10-150 μm; said magnetic particles have an apparent density in the range of 0.5-1.6 g/cm 3 ; and said magnetic particles have a saturation magnetization in the range of 40-150 emu/g.
Claim 13
Dependent Claim
84 words
A magnetophoretic display panel comprising; a pair of substrates, a plurality of cells between said substrates, each of said cells is filled with a liquid dispersion comprising magnetic particles, a dispersion medium, and a thickener, wherein, at least 90 wt % of said magnetic particles have a particle size in the range of 10-150 μm; said magnetic particles have an apparent density in the range of 0.5-1.6 g/cm 3 ; and said magnetic particles have a saturation magnetization in the range of 40-150 emu/g.
Claim 14
Dependent Claim
23 words
A magnetophoretic display panel according to claim 11, wherein said magnetic particles comprise porous black iron oxide particles produced by reduction with hydrogen.
Claim 15
Dependent Claim
12 words
A magnetophoretic display panel according to claim 11 further comprising a colorant.
Claim 16
Dependent Claim
17 words
A magnetophoretic display panel according to claim 11, wherein said magnetic particles are coated with a resin.
Claim 17
Dependent Claim
22 words
A magnetophoretic display panel according to claim 14, wherein said magnetic particles comprise a magnetic material mixed with a resin and pulverized.
Claim 18
Dependent Claim
15 words
A magnetophoretic display panel according to claim 14, wherein said resin comprises a thermoplastic resin.
Claim 19
Dependent Claim
15 words
A magnetophoretic display panel according to claim 14, wherein said resin comprises a thermosetting resin.
Claim 20
Dependent Claim
13 words
A magnetophoretic display panel according to claim 14, wherein said coating is multi-layered.
Claim 21
Dependent Claim
32 words
A magnetophoretic display panel according to claim 14; wherein said multi-layered coating comprises a first resin coating and a second resin coating, and said first resin is different than said second resin.
Claim 22
Dependent Claim
29 words
A magnetophoretic display panel according to claim 11, wherein said magnetic material is selected from the group consisting of ferrite, γ-hematite, γ-ferrite oxide, barium ferrite and black iron oxide.
References Cited (Backward Citations)
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1995-09-29 | 1996-03-30 | 1996-09-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-09-29 | 2000-03-30 | 2000-09-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-09-29 | 2004-03-30 | 2004-09-29 | $7700.00 | Window Closed / Lapsed |