US2940866A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Heat sensitive copy sheet
Assignee: Unisys Corp
•
Filing: 1957-04-10
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Granted: 1960-06-14
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Expires: 1977-04-10
Abstract
No abstract record available.
Inventors
- 👤 Robert H Sprague
- 👤 Dominick R Friello
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 22:20
CPC Classifications
B; B41; B41M; B41M5/00; B41M5/26; B41M5/30; B41M5/337; B41M5/3375; Y; Y10; Y10S; Y10S428/00; Y10S428/913; Y10S430/00; Y10S430/165
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
116 words
A HEAT SENSITIVE COPYING SHEET COMPRISING A SUPPORT AND A HEAT SENSITIVE LAYER THEREON, THE HEAT SENSITIVE LAYER COMPRISING A COLORLESS DYE BASE DERIVED FROM A MEMBER OF THE GROUP CONSISTING OF THE TRIPHENYLMETHANE DYES AND STYRYL DYE BASES, AN ACID FORMING SUBSTANCE SELECTED FROM THE GROUP CONSISTING OF HYDRATED ZINC ACETATE, BENZAMIDE, CHLORACETAMIDE, 2-NAPHTHYLACETAMIDE, AND HYDOXYETHYLPHTHALIMIDE, FOR FORMING AN ACID IN THE PRESENCE OF HEAT, A FILM FORMER, AND A RELATIVELY STRONG BASE FOR MAINTAINING THE DYE IN ITS COLORLESS FORM AT ROOM TEMPERATURE, THE RATIO OF SAID ACID FORMING SUBSTANCE AND BASES BEING CHOSEN SO THAT IN THE PRESENCE OF HEAT SAID ACID FORMING SUBSTANCE WILL CONVERT THE COLORLESS BASE TO THE COLORED FORM.
Claim 2
Dependent Claim
116 words
A HEAT SENSITIVE COPYING SHEET COMPRISING A SUPPORT AND A HEAT SENSITIVE LAYER THEREON, THE HEAT SENSITIVE LAYER COMPRISING A COLORLESS DYE BASE DERIVED FROM A MEMBER OF THE GROUP CONSISTING OF THE TRIPHENYLMETHANE DYES AND STYRYL DYE BASES, AN ACID FORMING SUBSTANCE SELECTED FROM THE GROUP CONSISTING OF HYDRATED ZINC ACETATE, BENZAMIDE, CHLORACETAMIDE, 2-NAPHTHYLACETAMIDE, AND HYDOXYETHYLPHTHALIMIDE, FOR FORMING AN ACID IN THE PRESENCE OF HEAT, A FILM FORMER, AND A RELATIVELY STRONG BASE FOR MAINTAINING THE DYE IN ITS COLORLESS FORM AT ROOM TEMPERATURE, THE RATIO OF SAID ACID FORMING SUBSTANCE AND BASES BEING CHOSEN SO THAT IN THE PRESENCE OF HEAT SAID ACID FORMING SUBSTANCE WILL CONVERT THE COLORLESS BASE TO THE COLORED FORM.
References Cited (Backward Citations)
US1351071A
Cited
US2618573A
Cited
US2474084A
Cited
US2595957A
Cited
US2755200A
Cited
US2755201A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1963-06-14 | 1963-12-14 | 1964-06-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-06-14 | 1967-12-14 | 1968-06-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-06-14 | 1971-12-14 | 1972-06-14 | $7700.00 | Window Closed / Lapsed |