DE957149C - Process for the preparation of new monoazo dyes - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN PATENT OFFICE

ISSUED JANUARY 31, 1957

PATENT LETTERING

J & 957.149 CLASS 22a GROUP INTERNAT. CLASS C09b

C 8481 IVb / 22a

Dr. Paul Rhyner, Dr. Rudolf Rüegg and Dr. Robert Wittwer,

Basel, Switzerland)

have been named as inventors

CIBA Aktiengesellschaft, Basel (Switzerland)

Process for the preparation of new monoazo dyes

Patented in the territory of the Federal Republic of Germany on November 22, 1963

Patent application published on August 2, 1956

Patent issued January 10, 1957

The priority of the application in Switzerland of November 27, 1952 has been claimed

It was found that one. to new, valuable ones Monoazo dyes are obtained when using diazo compounds from amines of the formula

NH ₉

(i)

wherein one of the two X is a - SO ₂ CH ₃ group and

the other is a chlorine or, preferably, a hydrogen atom, with compounds of formula 15

NC ₂ H ₄ OH

C ₂ H ₄ OH

(2)

CH,

combined, where η is an integer with a value of 25 at most 2.

The aminobenzene-mono-methylsulfones used as starting materials in the present process of formula (i) can be obtained by methylating (for example with dimethyl sulfate) the corresponding nitrobenzene monosulfinic acids or their alkali salts and subsequent reduction of the nitro group obtained Nitrobenzolmethylsulfone be prepared to the amino group. They can also be obtained from the corresponding nitro-thiophenols, if the latter is methylated, the methylthioethers obtained oxidized to methyl sulfones and finally those present in the nitrobenzene methyl sulfones obtained Nitro group converted into an amino group in a manner known per se. You can do it too according to the method of French patent 829,926. As examples of so available The following starting materials may be mentioned: 2-chloro-aminobenzene-4-methylsulfone, 4-chloro-i-aminobenzene-2-methylsulfone and especially i-aminobenzene-4-methylsulfone and i-aminobenzene-2-methylsulfone. The azo components used in the present process are i-di - (/? - oxyethyl) -amino-3-methylbenzene and i-di - (/? - oxyethyl) -ammo-3-methyl-6-methoxybenzene into consideration.

The diazotization of the aminobenzene methyl sulfones mentioned can according to methods known per se, for. B. with the help of mineral acid, especially hydrochloric acid and sodium nitrite.

The coupling can also be carried out in a manner known per se, for. B. in neutral to acidic medium, optionally in the presence of sodium acetate or the like influencing the coupling speed Buffer substances.

After the coupling reaction has taken place, the dyes formed can be removed from the coupling mixture easy, e.g. B. separated by filtration, since they are only sparingly soluble in water.

The monoazo dyes obtained in this way are new. They correspond to the formula
40

X 0 "—1C" —iH ₂ "-!

X

N = N

NC ₂ H ₄ OH

C ₂ H ₄ OH

(3)

where η is an integer of at most 2, one of the two Xs is a —SO ₂ CH ₃ group and the other X is a chlorine or, preferably, a hydrogen atom.

These new monoazo dyes, especially the

chlorine-free dyes are very suitable for dyeing and printing structures, e.g. B. fibers and fabrics made from cellulose esters and ethers, but above all for dyeing acetate rayon and Formed from super-polyurethanes and super-polyamides, for example synthetic, linear polyamides and polyurethanes, as well as blended fabrics made from polyamide and acetate rayon threads.

The colorations produced on such structures with these new dyes are distinguished by the special purity and liveliness of their hue and good general fastness properties, in particular characterized by high lightfastness and good fastness to sublimation.

Compared to the dyes known from British patent specification 560 298, the according to the present process available next comparable new dyes the advantage of a greater yield and better drawability at 50 °. Own the new dyes a better drawability at 50 ° than that obtained according to Example 8 of U.S. Patent 2,151,857 known dye, which, by the way, produces dyeings on polyamide fibers that are less than good Have sublimation fastness than those that can be obtained with the new, according to the present process obtainable dyes.

In the following examples, unless otherwise specified, parts are parts by weight and the percentages are percentages by weight.

example 1

17 parts of i-aminobenzene-4-methylsulfone, 25 parts a 4N sodium nitrite solution and 30 parts of ice are concentrated in 40 parts of water with 25 parts Hydrochloric acid added. By cooling from the outside, the temperature during the diazotization is between ο held up to 5 °. The diazo solution is completely clear and colored pale gold yellow. You let them slowly to 22.5 parts of i-di - (/? - oxyethyl) -amino-3-methyl-6-methoxybenzene, which is dissolved in 40 parts of 2η-hydrochloric acid flow. A dark red solution is created, from which the dye comes through Neutralize with saturated sodium acetate solution precipitates. The sucked off and dried dye represents a red powder, which dissolves in sulfuric acid with a brownish red color and acetate art, eide and dyes polyamide fibers in scarlet orange-red shades of high lightfastness.

Example 2

20.5 parts of 2-chloro-i-aminobenzene-4-methylsulfone are concentrated in portions in 60 parts Sulfuric acid, in which 6.9 parts of sodium nitrite were dissolved, entered. By pouring on 400 parts of ice produce a clear, golden-yellow solution. The diazo solution obtained in this way is slowly left in nc a solution of 22.5 parts of i-di (/ 3-oxyethyl) amino-3-methyl-6-methoxybenzene and 40 parts of 2η-hydrochloric acid flow. The dye falls from the resulting dark red solution by adding saturated sodium acetate solution as scarlet 115. powder made up in concentrated sulfuric acid dissolves with a reddish brown color and dyes acetate rayon and polyamide fibers in vivid red tones.

The following table lists further dyes which, according to the iao in Examples 1 and 2 specified method from the components mentioned in columns I and II are available. In column III is in each case the color of the dried dye powder and in column IV the one with it Acetate rayon and polyamide fibers indicated.

I. II III IV Colorings on acetate Diazo component Azp component Color of the "dye rayon and poly
amide fibers I. l-aminobenzene-4-methyl- i ~ Di - (/? - oxyethyl) -amino- Orange red orange sulfone 3-methylbenzene 2 2-chloro-i-aminobenzene- i-Di- (jS-oxyethyl) -amino- scarlet scarlet 4-methyl sulfone 3-methylbenzene 3 i-aminobenzene-2-methyl- i-di- (j8-oxyethyl) -amino- Orange red orange sulfone 3-methylbenzene 4th the same i-Di - (/? - oxyethyl) -amino- Wine red scarlet 3-methyl-6-methoxybenzene 5 i-amino-4-chlorobenzene i-Di - (/ 9-oxyethyl) -amino- Orange red Red orange 2-methyl sulfone 3-methylbenzene

Claims (4)

Patent claims i. Process for the production of new monoazo dyes, characterized in that one diazo compounds from amines of the formula NH wherein one of the two X is a - SO ₂ CH ₃ group and the other X 'is a chlorine or hydrogen atom, with compounds of the formula NC ₂ H ₄ OH C ₂ H ₄ OH combined, where η is an integer with a value of at most 2. 2. The method according to claim 1, characterized in that that chlorine-free diazo compounds are used. 3. The method according to claim 1 and 2, characterized in that there is used as the azo component ι -Di- (| 8-oxyethyl} -amino-3-methyl-6-methoxybenzene used. 4. The method according to claim 1 to 3, characterized in that the coupling in weak acidic means is made. References considered: British Patent No. 560,298; U.S. Patent No. 2,151,857. © 609 577 / + 11 7.56 (609 777 1. 57)