DE1271858B - Process for the preparation of cationic azo dyes - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Int. CL:. C09b

German class: 22 a-3

Number: 1271 858

File number: P 12 71 858.0-43 (A 42292)

Filing date: February 9, 1963

Open date: 4th July 1968

The invention relates to a process for the preparation of cationic azo dyes of the formula

Method of manufacture

of cationic azo dyes

CH, - CO

■ - «

IO

15 applicants:

American Cyanamid Company,

Stamford, Conn. (V. St. A.)

Representative:

Dipl.-Ing. M. Licht and Dr. R. Schmidt,

Patent Attorneys, 7603 Oppenau, Allmendplatz 4

Named as inventor:

John Justin Randall,

South Bound Brook, N.J. (V. St. A.)

Claimed priority:
V. St. v. America February 28, 1962
(176448)

wherein (X) "represents an anion, by coupling diazotized 2-amino-6-acetylaminobenzthiazol in acid solution with N-phenyl morpholine in a ₂ o a known manner and subsequent reaction of the azo dye thus obtained with methylating agents. These dye salts useful for blue coloring Such fibers or masses of polyacrylonitrile and other polymers which have acidic or ionic character, for example those of the formula

H ₃ CO

N (CH ₂ CH ₂ OH) ₂

Cl

where X stands for Cl (German Patent 963 176, page 7, lines 15 to 20), or those of the formula

/ CH ₂ - CH ₂ \

O X '

CH ₂ - CH ₂

wherein X means (p-CH ₃ -C ₆ H ₄ SO ₃ ) "(German Auslegeschrift 1 050 940, column 3, lines 66/67, and column 4, line 1).

The previously known color salts of this class, with which one can polyacrylonitrile and other fibers has colored, but show certain deficiencies, such as insufficient uniformity of the colorations achieved, poor reproducibility both in hue and in color depth and sensitivity to Changes in the pH value and mechanical stresses on the fibers dyed with them. A Another serious defect is their so-called »red tinge«. The dyes afflicted with it result Admittedly acceptable blue colorations in daylight, but in artificial light they get an ugly color red appearance.

Surprisingly, it has now been found that this deficiency is found in those which can be produced according to the invention

K »56» / «9

cationic dyes of the formula (I) do not occur, as comparative tests with very numerous similar colored salts. The new cationic azo dyes show no reddish cast and are also particularly notable for the uniformity of the colorations achieved alone as well as in a mixture with other dyes. This result, which is just in terms of otherwise extensive agreement in structure with the comparison substances was completely unexpected, is apparently based on the relatively slow absorption speed of the new color salts. Since the known dye salts of this class are absorbed much faster and therefore unevenly colored result, they are also suitable for the preparation of mixtures with other slower absorbing dyes Cannot be used to achieve certain color tones (brown, olive, navy blue and blue-black). In contrast, the cationic dyes prepared according to the invention have absorption speeds which are comparable to those of other known color salts of this class of dyes. she can thus be used with other cationic dyes with similar or the same absorption speeds without any risk be mixed.

For the quaternization of the by diazotizing 2-amino-6-acetyIaminobenzthiazol and domes in acidic solution with N-phenylmorpholine produced by known process steps dye particularly suitable established methylating agents are dimethyl sulfate, methyl chloride, methyl iodide, Methyl o- or p-toluenesulfonate, a mixture of o- and p-methyl toluenesulfonates or methyl perchlorate.

Dye salts prepared according to the invention are generally suitable for dyeing fibers which consist at least partially of anionic polymers, d. H. thermoplastic, linear polymers with negatively charged groups on the polymer chain. These polymers are known in the art. In general, they are either by copolymerization or by homopolymerization of a Monomers containing anionic groups prepared. In certain cases, however, they can by post-treating a nonionic polymer with a reactant such as a sulfonating agent, getting produced. In addition, the anionic groups, which the dye character determine also to be introduced as end groups in a vinyl polymer chain through the Using a suitable polymerization initiator, such as persulfate, or by using a suitable chain stoppers such as sulfite. In this case it is not necessary to use an anionic monomer to use. But once the polymer has been made, the structure of the anion is its own Usefulness in the context of the invention is insignificant.

While the dyes prepared in accordance with the invention can be used to make polymers color that even only a small number of anionic sites that are then always in the whole polymer chain recurring, so for practical purposes it is advisable to use / fibers made from polymers exist, 'in which the anionic groups in an amount of at least 10 millimoles per kilogram Polymer are present, preferably on the order of about 25 to 100 millimoles per kilogram. Even higher concentrations can be present, but this is not necessary.

As examples of anionic polymers to be colored with the dyes which can be prepared according to the invention are mentioned:

1. Acrylonitrile-methyl methacrylate copolymers with anionic end groups introduced by means of the polymerization catalyst and / or chain stopper;

2. Acrylonitrile-methylvinylpyridine-vinyl acetate terpolymers with anionic end groups;

3. Acrylonitrile-styrene-sulfonic acid copolymers (see U.S. Patent 2,837,500);

4. Acrylonitrile-methyl methacrylate-styrenesulfonic acid terpolymers (see U.S. Pat. No. 2,837,501);

5. Acrylonitrile - vinylidene chloride - polyvinyl - pyrrolidone terpolymers with anionic end groups;

6. Acrylonitrile-vinyl chloride copolymers with anionic end groups;

7. Vinylidene-dinitrile-vinyl acetate copolymers with anionic end groups and 8. Ethylene glycol, terephthalic acid or dimethyl terephthalate and sulfoterephthalic acid condensation polymers.

Polyacrylonitrile fibers in which the acrylonitrile monomer has been copolymerized with an acidic or anionic monomer or which anionic end groups, such as the products listed above, can be successfully with the dyeing dyes produced according to the invention. The dyeings obtained show excellent adhesive strength, Uniformity and a brilliant blue tint.

Although perhaps the main advantage of the dyes made in accordance with the present invention is uniformity of the coloration achieved, many other properties are still advantageous: The dye . does not stain acetate; the tints achieved with it can be adjusted through the sodium chloride content in the dye bath. The dyes can be used together with various acids in the Dyebath, such as acetic acid, formic acid or sulfuric acid. Shades and depths of color that match any of these acids obtained are uniform. The colors on the products can be reproduce flawlessly.

In the examples, unless otherwise specified, parts are parts by weight and percentages Percentages by weight and temperatures are given in degrees Celsius.

example 1

20.7 parts of 2-amino-6-acetylaminobenzothiazole are suspended in 75 parts by volume of 90% strength formic acid and added at 0 to 5 ° to a solution that is obtained by mixing 110 parts (60 parts by volume) concentrated sulfuric acid and 50 parts of water and cooled to 5 to 0 °. That The whole thing is cooled down to -5 to 0 °. Then 7.0 parts of sodium nitrite in 50 parts by volume of water dissolved and added to the above solution over half an hour, the temperature is held at -5 to 0 °. It is stirred for half an hour at -5 to 0 °. When the diazotization is complete, enough ice is added that the volume of the reaction mixture doubles. Parts of N-phenylmorpholine are in 120 parts

Glacial acetic acid dissolved, tempered to 0 to -5 ° and the suspension added to the diazo compound. The whole thing is diluted to 2000 parts by volume with water and stirred for half an hour. 100 parts of sodium acetate are added to adjust the pH to bring it to 1.0. After further stirring this will be

CH, - CNH

Product deposited by dilution with water to 3000 parts by volume. 200 parts by volume of concentrated ammonium hydroxide solution are added. The product is filtered, washed with water until the filtrate is free of mineral acid, and dried at 100 °. It conforms to the formula

N = N / CH ₂ CH ₂ V
NO

CH ₂

The yield is about 79.2% of theory.

25 parts of this product and 650 parts of monochlorobenzene are heated to boiling (134 °) and the water is drawn off with 50 parts of monochlorobenzene. The residue is cooled to 110 °, then 62.5 parts of the isomer mixture of methyl o- and p-toluenesulfonate are added. That The whole thing is heated on the reflux condenser (110 to 115 °) until the quaternization is complete (approx 5 hours). The precipitated reaction product is collected with 150 parts of cold monochlorobenzene washed, taken up again in 300 parts of monochlorobenzene, boiled for 15 minutes, filtered and again washed with cold monochlorobenzene.

To clean the product, 5 parts are dissolved in 200 parts of glacial acetic acid at 70 ° and filtered hot. 500 parts of tetrahydrofuran are added to the filtrate with stirring. Then 50 parts Heptane added. The precipitated product is collected with 100 parts of tetrahydrofuran and Washed 50 parts of heptane and then dried at 75 °. It conforms to the formula

CH, CNH

\ / LJH ₂ - Cn ₂ \

V-N = N- / V-NO

W ^X CH ₂ - CH ₂ /

CH ₃

(III)

The yield is 3.1 parts.

Used as methylating agent instead of the isomer mixture of methyl o- and p-toluenesulfonate a mixture of methyl o- and p-toluenesulfonate in a volume ratio of 1: 1 is obtained similar colored salts in good yields.

Dyeing prescription

The dye salt obtained according to Example 1 is to a fineness below 0.45 mesh openings per Shredded millimeters and processed into the following mixture:

2.0 parts dye salt,

2.8 parts sulfamic acid,

1.3 parts of a nonionic polyoxyethylene ether,

20.6 part g ^ boric acid.

26.7 parts

55

The mixture is passed through a sieve with 0.9 mesh openings per millimeter.

Part of the mixture obtained is dissolved in 500 parts of water. From this solution are 50 parts used as a dye solution together with 150 parts of water for a dye bath. This becomes 1 part Given 10% sodium chloride solution and 2 parts of a 5% solution of 28% acetic acid. In addition then give three 5 g strands of dry fibers of a copolymer of 94% acrylonitrile and 2% Methyl acrylate. The bath is heated to 93 ° and held at this temperature for 1 hour. then the strands are removed, washed first with water, then at 71 ° in a 0.1% strength Soap solution washed for 2 to 5 minutes, washed again with water and finally dried. The blue colorations obtained are of uniform depth of color.

Example 2

Example 1 is repeated, but the isomer mixture of methyl o- and p-toluenesulfonate is replaced by the amounts of dimethyl sulfate or methyl iodide given below. With the so produced Color salts, polyacrylonitrile with anionic sites in the molecule is colored in blue shades.

Methylating agent Applied amount
in percent by weight Hue of
Coloring on
Polyacrylonitrile Dimethyl sulfate
Methyl iodide 42
58 blue
blue

The perchlorate salt in which (X) in the formula (I) = ClO ₄ "is prepared by adding an equimolecular amount of perchloric acid to an aqueous acidic solution of the methyl sulfate salt in which (X)" in the formula (I) = CH ₃ SO ₄ T is.

Claims (1)

Claim: Process for the production of cationic azo dyes, characterized in that that one diazotized 2-amino-6-acetylaminobenzothiazole in acidic solution with N-phenylmorpholine couples and then with methylating agents to form cationic azo dye open of the formula CH ₂ CH, CO-NH wherein (X) is an anion. Documents considered: German Patent No. 963 176; German interpretative document No. 1 050 940. When the application was announced, a coloring table with explanations was laid out.