DE419431C - Process for the production of azo dyes which are resistant to absorption from nitrosamine dyes - Google Patents

Description

Process for the production of steam-resistant azo dyes from nitrosamine dyes. When using the nitrosamine inks in multi-color printing at the same time as others Dyes makes itself felt the disadvantage that the nitrosamine colors under certain circumstances not tolerate the steaming, but instead either lose a lot of strength and fade or change in tone.

It has now been found that nitrosamine paints, i.e. H. Mixtures of Nitrosamines and Oxynaphthoesäurearyliden or bodies with a couplable Methylene group, which have aromatic nitro or nitroso compounds as oxidizing agents are added, are so steam resistant that it succeeds through use such nitrosam print colors even after several hours of steaming, as it is, for. B. at Multicolor printing with tannin and most stain colors is essential, the dye to develop with certainty in full strength and pure nuance.

In the German patent 298236 a method is described, to make the nitrosamine colors steam resistant, which consists in being neutral Chromates or other metal salts added, which act with azo dyes for steaming Form resistive paints. It could not therefore be foreseen that organic Oxidizing agents, with which there can be no question of a protective varnish formation, would have the same effect.

Mixtures of the nitrosamine alkali salts are suitable as nitrosamine colors, which z. B. from nitroanilines, nitrotoluidines, nitroanisidines, chloranilines, Chlornitroanilinen, dianisidine and other diazotizable bases can be obtained can, with the alkali salts of z. B. Oxynaphthoic acid arylides and of bodies, which contain a methylene group capable of coupling, for example pyrazolone derivatives or derivatives of (3-ketone aldehyde, such as acetoacetic and diacyl acetic arylides.

The following are mentioned as aromatic nitro or nitroso compounds: nitrosulphonic acid salts of the benzene, naphthalene and anthraquinone series. and their halogen derivatives, nitrosonaphthol sulfonic acid salts, nitrophenol sulfonic acid salts and others. Example. Multi-color printing on Kaliko The white goods are printed with the following printing inks: I. Nitrosamine color: 22.5 g of 2,3-oxynaphthoic anilide, 19.5 g caustic soda, 97 percent, III g nitrosamine paste of the m-nitro-p-to- luidins, corresponding to 14J9 base, 5oo g starch carrier thickening, 50 g sodium nitrobenzenesulfonate, 297 g of water 1000 g. II. Basic color: 1 5 g pure green LB, 10 g glycerine, 15 g acetin, 8o g acetic acid 6 ° Be, 6 g tartaric acid i: a, 400 g acetic acid starch thickener (containing zoo g acetic acid 6 ° B6 in kg), 9o g tannic acetic acid i: i, 384 g water 1000 g. After drying, the mixture is steamed for one to one and a half hours in a closed steam kettle and the development of the dyes is brought about by a passage in the following bath at about 60 °: 30 g of acetic acid 8 ° B6 and iog tartar to 11 .

It is then soaped at about 30 °, rinsed and dried. You get a bright red with green accompanying color.

Depending on the choice of nitrosamine and accompanying colors, you get brilliant ones Prints in all nuances.

Instead of the nitrobenzenesulfonic acid salt, others of the abovementioned aromatic nitro or nitroso compounds are added. The proportions depend on the amount of dye used and the duration of the Steaming process.

Claims (1)

PATENT REQUEST: Process for the production of steam-resistant azo dyes from nitrosamine inks, characterized in that the printing inks are aromatic nitro or nitroso compounds are added as oxidizing agents.