DE1131640B - Process for dyeing structures made of cellulose triacetate - Google Patents

Description

Because of its hydrophobic nature, cellulose triacetate, which is similar in color to terephthalic acid polyesters, is known to be difficult to dye from an aqueous medium. Although it has already been proposed to work in the presence of so-called carriers, and it is z. B. known that cellulose triacetate fibers by means of disperse dyes, which were originally developed for cellulose 2V ₂ acetate, can be dyed in an aqueous medium at boiling point, if the dyed material in the presence of a carrier mixture consisting of benzanilide and dimethyl terephthalate, with the aqueous dye dispersion treated.

Also known is a process for dyeing structures made of cellulose triacetate with disperse dyes, that consists in dyeing in the presence of esters of salicylic acids containing alkyl groups in emulsified form, e.g. B. in the presence of the o-, m- or p-cresotinic acid methyl ester.

It has now been found that structures made of cellulose triacetate can, surprisingly, ^{be dyed advantageously from an aqueous bath at temperatures above 100 °} C. without using an organic carrier, if baths are used which contain complex 1: 2 chromium or cobalt compounds of sulfonic acid group-free monoazo dyes as dyes contain at least 10 g per liter of a water-soluble alkali salt of an inorganic acid or an organic carboxylic acid of low molecular weight.

As complex compounds of azo dyes come here z. B. the 1: 2 complex compounds of chromium and cobalt, the two sulfonic acid group-free monoazo dyes, especially two o, o'-dioxymonoazo dyes free of sulfonic acid and carboxyl groups on a metal atom complex bound included. A large number of such 1: 2 complexes are known, e.g. B. from the French Patents 953594, 1030656, 1040723, 1058651, 1061284, 1061365, 1061060, 1085262 and from U.S. Patent 2551012.

Sodium chloride, potassium chloride, potassium bromide and sodium sulfate are advantageously used as water-soluble salts and the like. The amount of salt to be used can be freely selected within wide limits. The optimal one The amount can easily be determined for each individual dye by means of preliminary tests on a case-by-case basis; in the in general, amounts of salt up to 50 g of salt per liter of dye liquor turn out to be, depending on the desired depth the coloring as sufficient.

The pH of the dyebath is preferably kept between 6 and 8, and the process for dyeing structures can be used
made of cellulose triacetate

Applicant:
CIBA Aktiengesellschaft, Basel (Switzerland)

Representative: Dr.-Ing. F. Wuesthoff, Dipl.-Ing. G. Pulse and Dipl.-Chem. Dr. rer. nat. E. Frhr. v. Pechmann, patent attorneys, Munich 9, Schweigerstr. 2

Claimed priority:
Switzerland of November 17, 1958 (No. 66 226)

Raymond Defago, Riehen,

and Dr. Robert Wittwer, Basel (Switzerland),

have been named as inventors

Dyebath, if appropriate, the auxiliaries customary in dyeing, but no organic carriers, added will.

The dye baths to be used in the present process can be prepared by methods known per se. The dye baths can be produced directly in the concentration required for dyeing by dissolving the metal-containing dyes and the water-soluble salts or buffer mixtures in water in any order. So-called stock solutions, which contain the substances mentioned in a high concentration, usually too high for dyeing, can also be diluted until the desired concentration is reached. In the baths that can be produced in this way, the dyeing is carried out ^{above 100 ° C., according to the invention.} It is generally advisable to choose temperatures of 110 to 140 ⁰ C.

According to the present process, while maintaining the good properties of the dyed Materials receive valuable, very even colorations which are generally lightfast and sublimation fast.

While the process of German patent specification 939206 does not provide any useful coloring on cellulose triacetate with 1: 2 chromium and cobalt complex compounds of sulfonic acid group-free monoazo dyes results, a deep coloration is obtained by the present method, and this is all the more surprising as the corresponding use of z. B. aniline chlorohydrate instead of sodium chloride neither on triacetate still leads to the goal on acetate silk.

209 610/351

In the following example, unless otherwise specified, the parts mean parts by weight, the Percentages by weight and temperatures are given in degrees Celsius.

example

In a dyebath containing 3 parts of the 1: 2 cobalt complex compound of the dye of the formula
OH HO Cl

-N = N-

SO ₂ NH ₈

in 5Q00 parts by weight of water of 5O ⁰ C, are added 150 parts of sodium chloride and is a triacetate with 100 parts. The temperature is raised to 125 ° C. in the course of 30 minutes and dyeing is carried out at this temperature for 60 minutes (pressure 1.5 atmospheres). After cooling to 100 ^° C., the fiber is rinsed hot and dried. A deep bordo color is obtained.

Good results are also obtained if instead of the specified 150 parts of sodium chloride 210 parts of sodium acetate, 200 parts of sodium formate or 180 parts of potassium chloride can be used.

With the metal complex compounds mentioned in the following table, column I, one obtains according to the above Method on cellulose triacetate fibers the nuances mentioned in column II.

I. Λ
\ / \ / ^! < - II 1. 1: 2 chromium complex compound of the dye of the formula ]
SO ₂ CH ₃ Cl NH ₂ ^ ₁ OH
ι HO 1: 2 chromium complex compound of the dye of the formula 1: 2 chromium complex compound of the dye of the formula SO ₂ -NH C = N Χ
ι I / \ I / \ OHH O OH
HO
/ \ i I '
CH ₃ ^CH 3 I 1 .cN-ZN-
O ₂ NJ, JN = NC ^ I / NN = N-- '' ^N
°° ^sJ \ / 'sy / X
{ i_ N = N - C; " Red CH ₃ 2. 1: 2 chromium complex compound of the dye of the formula OH HO Cl (y-χ strong bluish violet 3. blue 4th orange

5 I. -NN-C'- ' ⁰ ^ i CH ₃ _N = N - Y) -SO ₂ NH ₂ A- ' 6th II 1: 2 cobalt complex compound of the monoazo dye of
formula
OH HO Cl
i I! f ^X C = N V '' 1: 2 cobalt complex compound of the monoazo dye of
formula
OH HO Cl
ι ι ι II
SO ₂ CH ₃ Cl 1: 2 cobalt complex compound of the monoazo dye of 5. Γ Υ ^{Ν = Ν} -γ γ 'j NO ₂ 1: 2 cobalt complexv
formula
C. OH
CO-CH ₃ Reddish blue O ₂ N ^,. \ / A ■ i connection of the monoazo dye of the
) H HO
j ■■■ ^ ₁ -N = N-CH I.
Cl '' J ^x co-nhY "> 1: 2 cobalt complex compound of the monoazo dye of
formula
? ^H HO
A ι SO ₂ CH ₃ 6th j ^ν '' γ / orange I j
SO ₂ -NH k J
\ / χ / 7th Bordo 8th. Ruby red 9. yellow

I 131

An orange color is obtained according to the above procedure if, instead of the specified metal-containing Dye a corresponding amount of the dye used, which is according to Example 11 of the German Patent 925725 obtained by reacting 17 parts of 2-oxybenzoic acid-5-sulfonic acid-N, 3'-chlorophenylamide with 23 parts of the chromium-containing monoazo dye from diazotized! 2-Amino-1-oxybenzene-4-sulfonic acid amide and l- (3'-chlorophenyl) -3-methyl-5-pyrazolone, which has 1 atom per molecule of dye Contains chrome.

Claims (2)

PATENT CLAIMS: 1. A method for dyeing structures made of cellulose triacetate from an aqueous bath, characterized in that the material to be dyed at Tempe- Temperatures above 100 ⁰ C in a bath that contains a complex 1: 2 chromium or cobalt complex compound of a monoazo dye free of sulfonic acid groups and at least 10 g of a water-soluble alkali salt of an inorganic acid or low molecular weight aliphatic carboxylic acid, but no organic carrier. 2. The method according to claim 1, characterized in that dyeing at 110 to 140 ⁰ C. Considered publications:
German Patent No. 939 206;
British Patent No. 534,903;
Textil-Rundschau, 1956, pp. 520 and 523. 1 209 610/351 6.62