Claims
- 1. An organic solvent-soluble azo dye having the formula ##STR9## in which A and C each represents the phenyl ring;
- m is an integer from 1 to 3;
- x represents H or a NO.sub.2 group;
- y represents H, Cl, NO.sub.2 or alkyl or alkoxy containing from 1 to 3 carbon atoms;
- z represents H, Cl, or alkyl or alkoxy containing from 1 to 3 carbon atoms;
- R' represents alkyl containing from 1 to 3 carbon atoms; or R' represents the group ##STR10## R" represents H or alkyl containing from 1 to 3 carbon atoms; and R'" represents alkyl containing from 1 to 18 carbon atoms.
- 2. An organic solvent-soluble azo dye having the formula ##STR11##
- 3. An organic solvent-soluble azo dye having the formula ##STR12##
- 4. An organic solvent-soluble azo dye having the formula ##STR13##
- 5. An organic solvent-soluble azo dye having the formula ##STR14##
- 6. An organic solvent-soluble azo dye having the formula ##STR15##
THE PRIOR ART
This is a continuation, division, of application Ser. No. 153,868 filed June 16, 1971, now abandoned.
Heretofore, dyes compounded with organic solvents have been provided in the solid state, as powders, granules, flakes and the like. Many difficulties and problems have been encountered in the preparation and use of such products. In fact, powders of the solvent-containing dyes originate environmental dust and, in consequence, are difficult to handle. Agglomerates comprising the solvent-containing dyes have the drawback of a lower solubilization rate, which limits their usefulness.
On the other hand, when the traditional solvent-containing dyes (CF. e.g., C. I. 2nd Ed. 1956, Nos. 11020, 12055, 26100 and 26105) are used, it is not possible to employ concentrated solutions prepared in advance of use, inasmuch as the dyes are only sparingly soluble in the organic solvents, the solubility being, generally, only to the extent of 2% to 5%.
In consequence, additional expense is incurred due to the large amount of solvent needed, the requirement for special apparatus, and the increased shipping costs.
Even fluid pastes having a high dye concentration (solid dye finely divided in the support) present the inconvenience that it is not possible to obtain, rapidly, a homogeneous distribution of the dye in the material to be colored.
A primary object of this invention was to provide liquid dye compositions which could be prepared very simply and inexpensively, and which would have excellent tinctorial power, excellent stability against crystallization at low temperatures up to 0.degree. C, the capacity to dissolve or disperse instantly in the organic solvents, and particularly in the liquid petroleum distillates, thus making it possible to color those products during loading thereof in tank cars by means of a metering-mixing pump.
We have now found, surprisingly, that dyes of the general formula as set out and defined in the foregoing Abstract Of Disclosure are characterized by high coloring power and solubility in organic solvents, and are stable to recrystallization at low temperatures, by virtue of which characteristics said dyes can be used very advantageously for many purposes.
For instance, due to the chemical and physical characteristics thereof, the dyes of this invention are adapted to use as coloring agents for a wide variety of materials including inks, synthetic plastics, natural and synthetic resins, wood, oils, natural and synthetic waxes, and in the denaturing of organic liquids. In particular, these dyes are eminently suitable for use in coloring gasoline, gas oil, lubricating oils, and similar liquid petroleum distillates.
The various petroleum distillates are colored for the purpose of indicating both the source thereof, and the commercial and industrial applications for which they are intended.
The dyes embraced in formula (I) given in the foregoing Abstract, can be prepared for instance, --and the process for synthesizing the same is another object of this invention-- by reacting, in an anhydrous organic solvent, a dye of the general formula ##STR3## with a vinylether of the general formula
The intermediate dyes of formula II are prepared by known processes. For example, those intermediate dyes can be prepared by coupling a diazo-amino compound of the general formula ##STR4## with a coupling agent of the general formula: ##STR5## in which the substituents are as set forth hereinabove.
The anhydrous inert organic solvents useful as reaction medium include toluene, xylene and chlorobenzene.
As the acetylation reaction proceeds, the dye which is formed is dissolved in the organic solvent.
At the end of the reaction, the catalyst is neutralized by means of an anhydrous inorganic alkaline substance, such as Na.sub.2 CO.sub.3 ; K.sub.2 CO.sub.3 or the like, and/or by means of an aliphatic amine such as triethylamine, triethanolamine, etc. The neutralization is always effected under anhydrous conditions.
Under the working conditions, the dye is not extractable by aqueous alkaline solutions nor, in practice, even by aqueous acid solutions.
In fact, the quantity of dye extracted by aqueous acid solutions would be so small that the shade and intensity of the organic phase (for instance, gasoline and commercial gas oils) would not be considerably varied.
Liquid coloring compositions are obtained which can be used for coloring gasoline and gas oil.
The technical advantages of this invention are not limited to those illustrated above, which depend on the execptionally high solubility of the dyes in the organic solvents. Another advantage derives from the possibility of varying the substituents R', R", R'", X, Y and Z in the formula, to obtain shades from yellow to violet.
More specifically, the organic solvent-soluble monoazo dyes of the invention have the formula: ##STR6## in which A and C each represents the phenyl ring; m is an integer from 1 to 3;
z represents H, Cl, or alkyl or alkoxy containing from 1 to 3 carbon atoms or a lower-acylamino radical;
US Referenced Citations (2)
| Number |
Name |
Date |
Kind |
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2266142 |
Adams |
Dec 1941 |
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|
3586663 |
Kruckenberg |
Jun 1971 |
|
Continuations (1)
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Number |
Date |
Country |
| Parent |
153868 |
Jun 1971 |
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Patent Grant
4011209
