Patent US3785820A successfully refreshed from Google Patents.
US3785820A
Expired / Lapsed
US
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Photorecording process and photorecording member
Assignee: Canon Inc
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Filing: 1972-02-18
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Granted: 1974-01-15
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Expires: 1992-02-18
Abstract
Abstract A photochromic compound, particularly, spiropyran compound, is used for producing images. The difference of properties such as polarity and solubility between the colored species and the colorless species is utilized to produce the images and the spiropyran compound is maintained in a dense state to obtain a stable colored state.
Inventors
- 👤 E Inoue
- 👤 I Shimizu
- 👤 I Endo
- 👤 H Kobayashi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 01:51
CPC Classifications
G; G03; G03C; G03C1/00; G03C1/685; Y; Y10; Y10S; Y10S430/00; Y10S430/163
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
138 words
A photorecording process which comprises applying a blanket irradiation of a radiation to a photosensitive layer comprising a spiropyran compound and a non-polar dispersion medium in an exposure amount and time duration sufficient to produce (1) an initial colored image in an unstable monomolecular colored state and thereafter (2) a stable colored species of loW solubility adapted to form a stable colored image in a coagulated and associated stable colored state, said stable colored state uneffected by radiation and heat, wherein said stable colored state has a broader absorption spectrum then said initial monomolecular colored state, next wetting the surface of the colored photosensitive layer with a polar liquid dispersion medium toconvert it to a color-erasable colored state, and then applying an imagewise irradiation by a radiation capable of erasing the color-erasable colored state to form an image.
Claim 2
Independent Claim
122 words
A method for forming an image which comprises applying an imagewise irradiation by a radiation to a photosensitive layer comprising a spiropyran compound and a non-polar dispersion medium in an exposure amount and time duration sufficient to produce (1) an initial colored image in an unstable monomolecular colored state and therafter (2) a stable colored species of low solubility adapted to form a stable colored image in a coagulated and associated stable colored state, said stable colored state uneffected by radiation and heat, wherein said stable colored state has a broader absorption spectrum then said initial monomolecular colored state, and then removing the colored species of the spiropyran compound at the colored portion of the resulting colored image using a polar solvent.
Claim 3
Dependent Claim
20 words
A photorecording process according to claim 1 in which the non-polar dispersion medium is removed by vaporization after imagewise exposure.
Claim 4
Dependent Claim
39 words
A photorecording process according to claim 1 in which after producing stable colored images by imagewise exposure, the colored image surface is wetted with a polar dispersion medium to convert the stable colored image to a color-erasable colored state.
Claim 5
Dependent Claim
23 words
A photorecording process according to claim 5 in which the color-erasable state is erased by using a radiation, heat or a mixture thereof.
Claim 6
Dependent Claim
34 words
A method for forming an image according to claim 3 in which the non-colored species of the spiropyran compound at the non-colored portion of the stable colored image is removed using a non-polar solvent.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-01-14 | 1977-07-16 | 1978-01-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-01-14 | 1981-07-16 | 1982-01-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-01-14 | 1985-07-16 | 1986-01-15 | $7700.00 | Window Closed / Lapsed |