US3871886A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Photochromic copying method
Assignee: Ricoh Co Ltd
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Filing: 1973-06-21
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Granted: 1975-03-18
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Expires: 1993-06-21
Abstract
Abstract A stable image can be obtained by the copying method which comprises: applying image-wise ultraviolet rays having a wavelength lambda 1 corresponding to the absorption wavelength range of a spiropyran compound to a photochromic copying material comprising a support and a photosensitive layer containing the spiropyran compound, an aromatic or a cyclic ketone and a doped semi-conductive metal oxide; and subsequently applying ultraviolet rays having a wavelength lambda 2 capable of decomposing said ketone - either in the presence of an alcohol in the case of the ketone being aromatic or in the absence of alcohol in the case of the ketone being cyclic - to the whole surface of said copying material, or vice versa.
Inventors
- 👤 Jean Jules Achille Robillard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 19:04
CPC Classifications
G; G03; G03C; G03C1/00; G03C1/685; G03C1/72; G03C1/73
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
81 words
A COPYING METHOD SELECTED FROM THE GROUP CONSISTING OF: A. A FIRST METHOD WHICH COMPRISES IMAGEWISE EXPOSURE OF A PHOTOCHROMIC COPYING MATERIAL TO LIGHT RAYS HAVING A WAVELENGTH $1, SAID COPYING MATERIAL COMPRISING A SUPPORT AND A PHOTOSENSITIVE LAYER COMPRISING (A) A SPIROPYRAN, (B) AN AROMATIC OR A CYCLIC KETONE AND (C) A SEMICONDUCTIVE METAL OXIDE DOPED WITH AT LEAST ONE METAL, SAID WAVELENGTH $1, CORRESPONDING TO THE ABSORPTION WAVELENGTH OF THE SPIROPYRAN COMPOUND, SAID SPIROPYRAN COMPOUND HAVING THE GENERAL FORMULA:
Claim 2
Dependent Claim
81 words
A COPYING METHOD SELECTED FROM THE GROUP CONSISTING OF: A. A FIRST METHOD WHICH COMPRISES IMAGEWISE EXPOSURE OF A PHOTOCHROMIC COPYING MATERIAL TO LIGHT RAYS HAVING A WAVELENGTH $1, SAID COPYING MATERIAL COMPRISING A SUPPORT AND A PHOTOSENSITIVE LAYER COMPRISING (A) A SPIROPYRAN, (B) AN AROMATIC OR A CYCLIC KETONE AND (C) A SEMICONDUCTIVE METAL OXIDE DOPED WITH AT LEAST ONE METAL, SAID WAVELENGTH $1, CORRESPONDING TO THE ABSORPTION WAVELENGTH OF THE SPIROPYRAN COMPOUND, SAID SPIROPYRAN COMPOUND HAVING THE GENERAL FORMULA:
Claim 3
Dependent Claim
84 words
A method according to claim 1, wherein said spiropyran compound is selected from the group consisting of a compound of formula (I) wherein R1 R2 CH3, R3 C6H5, R4 OCH3, and R5 NO2; a compound of formula (I) wherein R1 R2 R3 CH3, and R4 R5 Br; a compound of formula (I) wherein R1 R2 R3 CH3, R4 H, and R5 NO2; a compound of formula (II) wherein R6 R7 CH3, R8 H, and R9 OCH3; a compound of formula (II) wherein R6 CH3,
Claim 4
Dependent Claim
27 words
A method according to claim 2, wherein the amount of ketone is from about 10 3*0.5 parts by weight per 1 part by weight of said spiropyran.
Claim 5
Dependent Claim
19 words
A method according to claim 2, wherein the alcohol is applied by coating the same onto the copying material.
Claim 6
Dependent Claim
54 words
A photochromic copying material comprising a support and a photosensitive layer comprising (a) a spiropyran, (b) an aromatic or a cyclic ketone and (c) a semiconductive metal oxide doped with at least one metal; said wavelength lambda 1 corresponding to the absorption wavelength of the spiropyran compound; said spiropyran compound having the general formula:
Claim 7
Dependent Claim
54 words
A photochromic copying material comprising a support and a photosensitive layer comprising (a) a spiropyran, (b) an aromatic or a cyclic ketone and (c) a semiconductive metal oxide doped with at least one metal; said wavelength lambda 1 corresponding to the absorption wavelength of the spiropyran compound; said spiropyran compound having the general formula:
Claim 8
Dependent Claim
85 words
A copying material according to claim 5, wherein said spiropyran compound is selected from the group consisting of a compound of formula (I) wherein R1 R2 CH3, R3 C6H5, R4 OCH3, and R5 NO2; a compound of formula (I) wherein R1 R2 R3 CH3, and R4 R5 Br; a compound of formula (I) wherein R1 R2 R3 CH3, R4 H, and R5 NO2; a compound of formula (II) wherein R6 R7 CH3, R8 H, and R9 OCH3; a compound of formula (II) wherein R6 CH3,
Claim 9
Dependent Claim
30 words
A copying material according to claim 5, wherein the amount of ketone employed is from about 10 3 *0.5 parts by weight per 1 part by weight of said spiropyran.
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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) | 1978-03-17 | 1978-09-16 | 1979-03-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-03-17 | 1982-09-16 | 1983-03-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-03-17 | 1986-09-16 | 1987-03-18 | $7700.00 | Window Closed / Lapsed |