Claims
- 1. An azo pigment obtained by a process wherein a diazotizable aromatic amine containing non-solubilizing substituents is diazotized in an anhydrous dipolar aprotic solvent with from stoichiometric to 20% in excess of stoichiometric amounts of nitrosyl sulfuric acid or nitrosyl chloride at a temperature of from -20.degree. to 40.degree. C.; the diazonium compound thus obtained is coupled with a coupling component selected from the group consisting of 2-hydroxy-3-naphthoylaminoarylides, acetoacetylaminoaryles, pyrazolones, hydroxy-quinolines, 2-hydroxy-3-naphthoylamino benzimidazolones and acetoacetylaminobenzimidazolones, to form an azo pigment; the acid is neutralized; and the pigment formed is thermally aftertreated without intermediate isolation.
- 2. An azo pigment as recited in claim 1 wherein the diazotizable aromatic amine contains carbamoyl, carboxylic acid anilide, acylamino or arylamino non-solubilizing substituents.
- 3. An azo pigment as recited in claim 1 wherein coupling is effected at -10.degree. to +50.degree. C.
- 4. An azo pigment as recited in claim 1 wherein the solvent is dimethyl formamide, dimethylacetamide, N-methylpyrrolidone, dimethyl sulfoxide, tetramethylene sulphone, tetramethyl urea or hexamethyl phosphoric acid tramide.
- 5. An azo pigment as recited in claim 1 wherein neutralizing is effected with a tertiary organic base.
- 6. An azo pigment as recited in claim 5 wherein the base is pyridine, dimethyl aniline or triethanol amine.
- 7. An azo pigment as recited in claim 1 wherein the maximum aftertreatment temperature is the boiling temperature of the aprotic solvent.
Priority Claims (1)
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2202773 |
Jan 1972 |
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Parent Case Info
This application is a continuation application of earlier filed copending application Ser. No. 027,721 filed Apr. 6, 1979, now abandoned, which application was a divisional application of earlier filed copending application Ser. No. 761,071, filed Jan. 21, 1977, now U.S. Pat. No. 4,182,708, which was a continuation-in-part of earlier filed copending application Ser. No. 619,460, filed Oct. 3, 1975, now abandoned, which in turn was a continuation of earlier filed copending application Ser. No. 325,549, filed Jan. 22, 1973, now abandoned.
US Referenced Citations (9)
Divisions (1)
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761071 |
Jan 1977 |
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Continuations (2)
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27721 |
Apr 1979 |
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325549 |
Jan 1973 |
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Continuation in Parts (1)
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619460 |
Oct 1975 |
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