Patent US4330473A successfully refreshed from Google Patents.
US4330473A
Expired / Lapsed
US
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Recording material
Assignee: ESCO Co LP
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Filing: 1980-11-26
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Granted: 1982-05-18
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Expires: 2000-11-26
Abstract
Abstract The present invention discloses novel fluoran compound useful as the lactone electron donative color-forming agents having the general formula: ##STR1## wherein, R 1 , R 2 and R 4 are respectively hydrogen, methyl or ethyl groups; R 3 is hydrogen or a methyl group; and R 5 is a phenyl group or a phenyl group substituted with from one to five methyl groups. The compound of the invention is soluble in aromatic solvents as well as in aromatic-aliphatic mixed solvents and also has excellent light fastness after developing color.
Inventors
- 👤 Yoshihiro Hatano
- 👤 Kenji Yamamoto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 15:00
CPC Classifications
B; B41; B41M; B41M5/00; B41M5/124; B41M5/132; B41M5/136; B41M5/145; B41M5/1455; C; C09; C09B; C09B11/00; C09B11/04; C09B11/10; C09B11/24
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
1 words
3-diethylamino-6-methyl-7-(2',4'-dimethylanilino)fluoran.
Claim 2
Dependent Claim
1 words
3-diethylamino-6-methyl-7-(2',4'-dimethylanilino)fluoran.
References Cited (Backward Citations)
US3669711A
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DE2110859A1
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US3721576A
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US3746562A
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JPS4734442U
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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) | 1985-05-17 | 1985-11-16 | 1986-05-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-05-17 | 1989-11-16 | 1990-05-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-05-17 | 1993-11-16 | 1994-05-18 | $7700.00 | Window Closed / Lapsed |