US3666947A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Liquid crystal imaging system having an undisturbed image on a disturbed background and having a radiation absorptive material dispersed throughout the liquid crystal
Assignee: Xerox Corp
•
Filing: 1971-01-06
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Granted: 1972-05-30
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Expires: 1991-01-06
Abstract
Abstract An imaging system wherein an imaging member comprising a composition comprising a material having a cholesteric liquid crystalline phase with radiation absorptive material dispersed throughout the liquid crystalline material, is provided with the liquid crystalline composition in its Grandjean or ''''disturbed'''' texture state, and the member is thermally imaged by imagewise heating image portions of said imaging material to a temperature at least about the cholesteric liquid-isotropic transition temperature range of the material and allowing said heated portions of said imaging material to return to a temperature within the cholesteric liquid crystalline mesophase temperature range of said material, whereby said imaged areas assume the focal-conic or ''''undisturbed'''' texture state in the desired image configuration. Images provided by the inventive system may be erased, and the imaging members used therein are typically reuseable.
Inventors
- 👤 Werner Erwin Louis Haas
- 👤 James E Adams
- 👤 John B Flannery Jr
- 👤 Bela Mechlowitz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 14:31
CPC Classifications
B; B41; B41M; B41M5/00; B41M5/26; B41M5/28; B41M5/281; G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/132; G02F1/133; G02F1/1333; G02F1/133362; G02F1/137; G02F1/13718
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
17 words
The method of claim 1 wherein said layer of imaging composition is provided on a supporting substrate.
Claim 2
Dependent Claim
12 words
The method of claim 2 wherein the supporting substrate is substantially transparent.
Claim 3
Dependent Claim
23 words
The method of claim 3 wherein the imaged composition is observed between polarizers with transmitted light, and the transparent substrate is optically isotropic.
Claim 4
Dependent Claim
23 words
The method of claim 1 wherein the radiation absorptive material is particulate material of average particle size not greater than about 5 microns.
Claim 5
Dependent Claim
23 words
The method of claim 5 wherein the radiation absorptive material is particulate material of average particle size not greater than about 1 micron.
Claim 6
Dependent Claim
23 words
The method of claim 1 wherein the radiation absorptive material is particulate material which is substantially insoluble in the cholesteric liquid crystalline material.
Claim 7
Dependent Claim
21 words
The method of claim 1 wherein the radiation absorptive material is soluble in or miscible with the cholesteric liquid crystalline material.
Claim 8
Dependent Claim
21 words
The method of claim 1 wherein the radiation absorptive material comprises not greater than about 20 percent of the imaging composition.
Claim 9
Dependent Claim
24 words
The method of claim 1 wherein said layer of imaging composition is of thickness in the range between about 1 and about 50 microns.
Claim 10
Dependent Claim
18 words
The method of claim 1 wherein said layer of imaging composition is overcoated with a substantially transparent overcoating.
Claim 11
Dependent Claim
19 words
The method of claim 11 wherein said substantially transparent overcoating is of thickness not greater than about 10 mils.
Claim 12
Dependent Claim
33 words
The method of claim 1 wherein the energy applied to the layer of imaging composition is in the range between about 1 millijoule/cm2 and about 100 millijoules/cm2 of surface area of said layer.
Claim 13
Dependent Claim
19 words
The method of claim 1 wherein the energy is applied in imagewise configuration to the layer of imaging composition.
Claim 14
Dependent Claim
26 words
The method of claim 14 wherein the energy is applied by exposing the layer of imaging composition to radiant energy through a mask in image configuration.
Claim 15
Dependent Claim
17 words
The method of claim 15 wherein the source of said radiant energy is a gas discharge lamp.
Claim 16
Dependent Claim
30 words
The meThod of claim 15 wherein the exposure time is not greater than about 10 seconds and wherein the source of said radiant energy is a Xenon gas discharge lamp.
Claim 17
Dependent Claim
49 words
The method of claim 1 wherein said imaging composition comprises a mixture of a material having a cholesteric liquid crystalline mesophase and at least one material selected from the group consisting of: materials having a nematic liquid crystalline mesophase, materials having a smectic liquid crystalline mesophase, and mixtures thereof.
Claim 18
Dependent Claim
18 words
The method of claim 1 wherein the imaging composition comprises a mixture of oleyl cholesteryl carbonate and p-methoxy-benzylidene-p''-n-butylaniline.
Claim 19
Dependent Claim
17 words
The method of claim 1 wherein the imaging composition comprises a mixture of cholesteryl erucate and p-methoxy-benzylidene-p''-n-butylaniline.
Claim 20
Dependent Claim
26 words
The method of claim 1 wherein said imaging composition exhibits cholesteric liquid crystalline characteristics in the temperature range between about 20* C. and about 30* C.
Claim 21
Dependent Claim
40 words
The method of claim 1 wherein before applying the energy to produce the imagewise effect, the layer of imaging composition is thermally biased to a temperature not greater than about 5* C. below the isotropic transition temperature of the composition.
Claim 22
Dependent Claim
48 words
An imaging method comprising: a. providing and imaging a layer of imaging composition by the method of claim 1, and b thereafter uniformly applying an external force to said imaging member to erase the image by uniformly providing the layer of imaging composition in the Grandjean texture state.
Claim 23
Dependent Claim
24 words
A repetitive imaging method comprising repeating steps a and b of claim 23 a plurality of times using the same layer of imaging composition.
Claim 24
Dependent Claim
18 words
The method of claim 1 wherein the layer of imaging composition has a Lambda in the visible spectrum.
References Cited (Backward Citations)
US2976415A
Cited
US3114836A
Cited
US3401262A
Cited
US3415991A
Cited
US3529156A
Cited
US3569709A
Cited
US3604930A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-05-30 | 1975-11-29 | 1976-05-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-05-30 | 1979-11-29 | 1980-05-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-05-30 | 1983-11-29 | 1984-05-30 | $7700.00 | Window Closed / Lapsed |