Patent US3852093A successfully refreshed from Google Patents.
US3852093A
Expired / Lapsed
US
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Heat-sensitive copy-sheet
Assignee: 3M Co
•
Filing: 1972-12-13
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Granted: 1974-12-03
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Expires: 1992-12-13
Abstract
Abstract A transparent colored film product, which becomes clear and colorless at image areas when heated thermographically, contains a p-quinoneimine color body and a mild reducing agent.
Inventors
- 👤 Leary K O
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 14:12
CPC Classifications
B; B41; B41M; B41M5/00; B41M5/26; B41M5/28; B41M5/286; Y; Y10; Y10S; Y10S430/00; Y10S430/165
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
36 words
COLORED SHEET MATERIAL CAPABLE OF UNDERGOING LOCALIZED LOSS OF COLOR WHEN THERMOGRAPHICALLY HEATED IN PRESENCE OF A REDUCING AGENT AND CONTAINING A P-QUINONEIMENE COLOR BODY IN A FILM-FORMING BINDER WHEREIN SAID COLOR BODY HAS THE STRUCTURE
Claim 2
Dependent Claim
36 words
COLORED SHEET MATERIAL CAPABLE OF UNDERGOING LOCALIZED LOSS OF COLOR WHEN THERMOGRAPHICALLY HEATED IN PRESENCE OF A REDUCING AGENT AND CONTAINING A P-QUINONEIMENE COLOR BODY IN A FILM-FORMING BINDER WHEREIN SAID COLOR BODY HAS THE STRUCTURE
Claim 3
Dependent Claim
17 words
Sheet material of claim 1 disposed in face-to-face relationship with a second sheet containing said reducing agent.
Claim 4
Dependent Claim
12 words
Sheet material of claim 1 wherein is included a said reducing agent.
Claim 5
Dependent Claim
19 words
Sheet material of claim 3 wherein said reducing agent is a hydroquinone, catechol, resorcinol or trihydroxy-aromatic mild reducing agent.
Claim 6
Dependent Claim
14 words
Sheet material of claim 3 wherein said reducing agent is contained in said binder.
Claim 7
Dependent Claim
27 words
Sheet material of claim 3 wherein said reducing agent is contained in a different film-forming binder as a separate stratum adjacent the stratum containing said color body.
Claim 8
Dependent Claim
17 words
Sheet material of claim 6 wherein said strata are supported on a thin flexible transparent film carrier.
References Cited (Backward Citations)
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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) | 1977-12-02 | 1978-06-03 | 1978-12-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-12-02 | 1982-06-03 | 1982-12-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-12-02 | 1986-06-03 | 1986-12-03 | $7700.00 | Window Closed / Lapsed |