Patent US4255327A successfully refreshed from Google Patents.
US4255327A
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US
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Direct black dye
Assignee: Crompton and Knowles Corp
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Filing: 1979-03-27
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Granted: 1981-03-10
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Expires: 1999-03-27
Abstract
Abstract This invention relates to a new group of trisazo compounds that are useful as direct dyes for cellulosic textiles, paper and leather; imparting a black coloration thereto. The new dye is intended to replace the widely used paper dye known as C.I. Direct Black 38--a dye synthesized from an intermediate (benzidine) whose use is being curtailed because it is a known carcinogen.
Inventors
- 👤 David A. Brode
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 21:24
CPC Classifications
D; D21; D21H; D21H21/00; D21H21/14; D21H21/28; C; C09; C09B; C09B31/00; C09B31/16; C09B31/18
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
105 words
A tri or tetrasulfonic compound having the structure ##STR9## where A is ##STR10## where R 1 is H, SO 3 M, lower alkyl, lower alkoxy, halogen, COOM, NHCO lower alkyl, NHCOCOOM, NO 2 or CN and R 2 is H, SO 3 M, lower alkyl, lower alkoxy, halogen or COOM; ##STR11## wherein R 3 is H, lower alkyl or lower alkoxy; R 4 is H, lower alkyl, lower alkoxy or NHCO lower alkyl; R 5 is H or SO 3 M; R 6 is H or lower alkyl and M is H, Na, K, Li, NH 4 or a mono, di or tri alkanol amine.
Claim 2
Dependent Claim
105 words
A tri or tetrasulfonic compound having the structure ##STR9## where A is ##STR10## where R 1 is H, SO 3 M, lower alkyl, lower alkoxy, halogen, COOM, NHCO lower alkyl, NHCOCOOM, NO 2 or CN and R 2 is H, SO 3 M, lower alkyl, lower alkoxy, halogen or COOM; ##STR11## wherein R 3 is H, lower alkyl or lower alkoxy; R 4 is H, lower alkyl, lower alkoxy or NHCO lower alkyl; R 5 is H or SO 3 M; R 6 is H or lower alkyl and M is H, Na, K, Li, NH 4 or a mono, di or tri alkanol amine.
Claim 3
Dependent Claim
76 words
The method of making a compound of claim 1 which comprises diazotizing an optionally substituted aminobenzene having the structure ##STR12## or a naphthylamine having the structure ##STR13## and coupling to an optionally substituted aniline, having the structure ##STR14## or a naphthyl amine having the structure ##STR15## rediazotizing the resulting monoazo compound and coupling to Gamma acid in alkaline medium; rediazotizing the resulting disazo compound and coupling to m-phenylenediamime sulfonic acid or a lower alkyl homolog thereof.
Claim 4
Dependent Claim
10 words
The compound according to claim 1 having the structure: ##STR16##
Claim 5
Dependent Claim
10 words
A compound according to claim 1 where M is Na.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-03-09 | 1984-09-08 | 1985-03-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-03-09 | 1988-09-08 | 1989-03-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-03-09 | 1992-09-08 | 1993-03-10 | $7700.00 | Window Closed / Lapsed |