US3725416A
Expired / Lapsed
US
⏱️ 0.0 years remaining
7-piperidinofluoran
Assignee: Yamamoto Chemicals Inc
•
Filing: 1970-11-30
•
Granted: 1973-04-03
•
Expires: 1990-11-30
Abstract
Abstract Compounds and a pressure-sensitive copying sheet containing said compounds as a color-forming agent art provided said compounds have the following general formula: WHEREIN EACH OF R1 and R2 is independently alkyl of up to 4 carbon atoms; and each of X and Y is independently hydrogen, halogen of alkyl of up to 4 carbon atoms. D R A W I N G
Inventors
- 👤 K Yamamoto
- 👤 N Sasaki
- 👤 M Terayama
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 00:01
CPC Classifications
C; C09; C09B; C09B11/00; C09B11/04; C09B11/10; C09B11/24
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
12 words
A compound of claim 1 wherein said halogen is chlorine or bromine.
Claim 2
Dependent Claim
1 words
3-diethylamino-7-piperidinofluoran
Claim 3
Dependent Claim
1 words
3-diethylamino-5-methyl-7-piperidinofluoran
Claim 4
Dependent Claim
1 words
3-diethylamino-5-chloro-7-piperidinofluoran
Claim 5
Dependent Claim
1 words
3-dimethylamino-7-piperidinofluoran
Claim 6
Dependent Claim
1 words
3-dimethylamino-5-methyl-7-piperidinofluoran
References Cited (Backward Citations)
US3442908A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-04-02 | 1976-10-02 | 1977-04-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-04-02 | 1980-10-02 | 1981-04-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-04-02 | 1984-10-02 | 1985-04-03 | $7700.00 | Window Closed / Lapsed |