US4297005A
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Assignee: AT&T Inc
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Filing: 1979-06-25
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Granted: 1981-10-27
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Expires: 1999-06-25
Abstract
Abstract Display devices are described which contain, in addition to organic quinones and suitable organic solvent, a solid ionic conductor. Such display devices are advantageous because of exceptional persistence of the display. Thus, an image may be retained without application of electrical energy. In addition, these displays exhibit high optical contrast and low power consumption. Under certain conditions, these devices are non-linear (exhibit sharp thresholds) which permit multiplexing. This is highly advantageous in display device applications.
Inventors
- 👤 David W. Johnson, Jr.
- 👤 Shobha Singh
- 👤 LeGrand G. Van Uitert
- 👤 George J. Zydzik
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 23:15
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/15; G02F1/153; G02F1/1533; G02F1/1503
Claims Analysis
Total Claims: 46
Claim 1
Independent Claim
96 words
An electrochemical display device comprising: (a) first and second electrodes; (b) electrochemical solution in contact with the first and the second electrodes; (c) said electrochemical solution comprising: i. organic quinone which changes color under the influence of an electrical signal, ii. electrolyte, iii. organic solvent capable of dissolving said organic quinone; (d) characterized in that a solid cation ionic conductor separates the device into two cavities, each with its own electrode, one comprising the first electrode and the other comprising the second electrode and the two cavities are at least partially filled with said electrochemical solution.
Claim 2
Dependent Claim
96 words
An electrochemical display device comprising: (a) first and second electrodes; (b) electrochemical solution in contact with the first and the second electrodes; (c) said electrochemical solution comprising: i. organic quinone which changes color under the influence of an electrical signal, ii. electrolyte, iii. organic solvent capable of dissolving said organic quinone; (d) characterized in that a solid cation ionic conductor separates the device into two cavities, each with its own electrode, one comprising the first electrode and the other comprising the second electrode and the two cavities are at least partially filled with said electrochemical solution.
Claim 3
Dependent Claim
15 words
The electrochemical display device of claim 1 in which the cation ionic conductor is β-alumina.
Claim 4
Dependent Claim
62 words
The electrochemical display device of claim 2 in which the cation in the cation ionic conductor is selected from the group consisting of Na + , K + , Li + , Ag + , Rb + , Tl + , NH 4 + , In + , NO + , Ga + , Cu + , H 3 O + .
Claim 5
Dependent Claim
15 words
The electrochemical display device of claim 3 in which the cation is Na + .
Claim 6
Dependent Claim
31 words
The electrochemical display device of claim 1 in which the cation ionic conductor is Na 1+x Zr 2 Si xl P 3-x O 12 where x varies from 0 to 3.0.
Claim 7
Dependent Claim
15 words
The electrochemical display device of claim 1 in which x varies from 1.8 to 2.4.
Claim 8
Dependent Claim
30 words
The electrochemical display device of claim 1 in which the cation ionic conductor is hollandite with nominal formula K 1 .6 Mg 0 .8 Ti 7 .2 O 16 .
Claim 9
Dependent Claim
17 words
The electrochemical display device of claim 1 in which the cation ionic conductor is Li 3 N.
Claim 10
Dependent Claim
22 words
The electrochemical display device of claim 1 in which the cation conductor is a B 2 O 3 -Li 2 O-LiCl glass.
Claim 11
Dependent Claim
15 words
The electrochemical display device of claim 1 in which the cation is an alkali-metal ion.
Claim 12
Dependent Claim
14 words
The electrochemical display device of claim 10 in which the cation is sodium ion.
Claim 13
Dependent Claim
18 words
The electrochemical display device of claim 1 in which the organic quinone has up to 100 carbon atoms.
Claim 14
Dependent Claim
18 words
The electrochemical display device of claim 12 in which the organic quinone contains three to six aromatic rings.
Claim 15
Dependent Claim
30 words
The electrochemical display device of claim 12 in which the organic quinone contains hydrocarbon substituents selected from the group consisting of aromatic rings, aliphatic rings, heterocyclic rings and aliphatic groups.
Claim 16
Dependent Claim
16 words
The electrochemical display device of claim 14 in which the hydrocarbon substituent is an alkane group.
Claim 17
Dependent Claim
24 words
The electrochemical display device of claim 14 in which the organic quinone is selected from the group consisting of 2-ethylanthraquinone, 2-tertiary-butylanthraquinone and benz[α]anthracene-7,12 dione.
Claim 18
Dependent Claim
22 words
The electrochemical display device of claim 1 in which the solvent is selected from the group consisting of dimethylsulfoxide, N,N-diethylformamide, and N,N-dimethylformamide.
Claim 19
Dependent Claim
14 words
The electrochemical display device of claim 1 in which the electrolyte comprises alkali-metal halide.
Claim 20
Dependent Claim
14 words
The electrochemical display device of claim 18 in which the electrolyte comprises sodium iodide.
Claim 21
Dependent Claim
14 words
The electrochemical display device of claim 1 in which the electrolyte comprises ammonium halide.
Claim 22
Dependent Claim
14 words
The electrochemical display device of claim 20 in which the electrolyte comprises ammonium iodide.
Claim 23
Dependent Claim
15 words
The electrochemical display device of claim 1 in which the electrolyte comprises quaternary ammonium halide.
Claim 24
Dependent Claim
15 words
The electrochemical display device of claim 22 in which the electrolyte comprises quaternary ammonium iodide.
Claim 25
Dependent Claim
19 words
The electrochemical display device of claim 23 in which the electrolyte comprises tetrabutylammonium iodide, tetrahexylammonium iodide or tetraheptylammonium iodide.
Claim 26
Dependent Claim
16 words
The electrochemical display device of claim 1 in which the electrochemical solution comprises in addition opacifier.
Claim 27
Dependent Claim
19 words
The electrochemical display device of claim 25 in which the opacifier comprises solid semiconductor substances and solid insulator substance.
Claim 28
Dependent Claim
24 words
The electrochemical display device of claim 26 in which the semiconducting substance has a conductivity of at least 10 -9 mhos/cm at room temperature.
Claim 29
Dependent Claim
22 words
The electrochemical display device of claim 26 in which the opacifier comprises 1-90 weight percent solid semiconductor substance, remainder solid insulator substance.
Claim 30
Dependent Claim
22 words
The electrochemical display device of claim 26 in which the opacifier comprises 20-70 weight percent solid semiconductor substance remainder solid insulator substance.
Claim 31
Dependent Claim
24 words
The electrochemical display device of claim 29 in which the opacifier consists essentially of 40-60 weight percent solid semiconductor substance, remainder solid insulator substance.
Claim 32
Dependent Claim
32 words
The electrochemical display device of claim 26 in which the solid semiconductor substance consists essentially of at least one suitably doped compound selected from the group consisting of uncolored, transition metal oxides.
Claim 33
Dependent Claim
48 words
The electrochemical display device of claim 31 in which the solid semiconducting substance consists essentially of at least one suitably doped compound selected from the group consisting of TiO 2 , ZrO 2 , GeO 2 , Nb 2 O 5 , and Ta 2 O 5 .
Claim 34
Dependent Claim
19 words
The electrochemical display device of claim 32 in which the dopant concentration ranges from 0.001 to 1.0 weight percent.
Claim 35
Dependent Claim
17 words
The electrochemical display device of claim 32 in which the semiconductor material is doped TiO 2 .
Claim 36
Dependent Claim
23 words
The electrochemical display device of claim 34 in which the dopant is iron in the concentration range of 0.005 to 0.025 weight percent.
Claim 37
Dependent Claim
108 words
The electrochemical display device of claim 26 in which the insulating substance is selected from the group consisting of BeO, MgO, ZnO, Al 2 O 3 , Ga 2 O 3 , Sc 2 O 3 , Y 2 O 3 , La 2 O 3 , Gd 2 O 3 , SiO 2 , Gd 2 O 3 , SiO 2 , BeAl 2 O 4 , ZnGa 2 O 4 , BeAl 2 O 4 , ZnGa 2 O 4 , MgAl 2 O 4 , Be 3 Al 2 Si 3 O 12 , GdAlO 3 , NaAlSi 2 O 6 and NaYO 2 .
Claim 38
Dependent Claim
24 words
The electrochemical display device of claim 26 in which the insulator substance consists essentially of a transition metal oxide sufficiently pure to be insulating.
Claim 39
Dependent Claim
28 words
The electrochemical device of claim 37 in which the insulating substance is selected from the group consisting of NaAlSi 2 O 5 and Al 2 O 3 .
Claim 40
Dependent Claim
16 words
The electrochemical device of claim 1 in which the electrochemical solution comprises in addition silver halide.
Claim 41
Dependent Claim
16 words
The electrochemical device of claim 39 in which the electrochemical solution comprises in addition ammonium halide.
Claim 42
Dependent Claim
17 words
The electrochemical device of claim 40 in which the electrochemical solution comprises in addition quaternary ammonium halide.
Claim 43
Dependent Claim
12 words
The electrochemical device of claim 41 in which the halide is iodide.
Claim 44
Dependent Claim
16 words
The electrochemical device of claim 1 in which the electrochemical solution comprises in addition a halogen.
Claim 45
Dependent Claim
12 words
The electrochemical device of claim 43 in which the halogen is iodine.
Claim 46
Dependent Claim
17 words
The electrochemical device of claim 1 in which the organic quinone is added as a quinoide salt.
References Cited (Backward Citations)
US4175838A
Cited
US4183631A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-10-26 | 1985-04-27 | 1985-10-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-10-26 | 1989-04-27 | 1989-10-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-10-26 | 1993-04-27 | 1993-10-27 | $7700.00 | Window Closed / Lapsed |