DE521123C - Process for the production of non-settling aqueous dye pastes - Google Patents

Description

Process for the preparation of non-settling aqueous dye pastes When using aqueous pastes from more or less finely divided. Substances usually have the disadvantage that these pastes tend to stand up Ball up and settle, making the paste if it is longer or shorter Is kept for time, no longer has a uniform composition. One has suggested adding gum, glue and other similar thickeners, however these additives have the disadvantage of mold formation.

It has now been shown that polychlorinated naphthalenesulfonic acids and their salts have particularly valuable properties in this regard. The addition of 2 ° (o sodium polychloronaphthalene sulfonate (calculated on the total weight of the Paste) to an aqueous paste, for example of Duranthren Gold Orange Y (p c h u 1 t z, color tables, 6th edition, volume i no. 76o) completely prevents the settling of the solid dye, and it has been shown that the paste despite Weeks of standing practically retains their uniform composition. These The effect is based on the formation of a stiff gel which, however, is easy to stir and quickly becomes thin when stirred or shaken.

Solutions or pastes, which polychloronaphthalene stdlfonsättren or their salts ent-. are not subject to damage from mold growth. The products also have valuable properties with regard to wetting.

L a u r e n t (Liebigs Annalen, 72, 300) already had the fact in 1849 recorded that the potassium salt of sulfonated tetrachloronaphthalene was precipitated forms a gel with water from alcoholic solution, but has this observation no technical application found so far.

The compounds used according to the invention are .by Sulfonation of a mixture of polychloronaphthalenes produced, which on average Contains 3 to 4.5 atoms of chlorine in the molecule. These substances can be through different known methods can be obtained, for example by that in the English patent 291 8q: 9 process described, namely by chlorination with chlorine gas in the presence of ferric chloride.

Example 1 Preparation of Polychlornaphthalinsulfonsäuren 3oo parts of a Polychlornaphtbalingemisches which is prepared by introducing chlorine gas in naphthalene in the presence of iron chloride at 1 30 to 16O ° C and contains an average of 3.5 atoms of chlorine in the molecule are heated at i5o ° C and then 300 parts of 22% oleum were added in the course of -io minutes at 150 to 160 ° C. The temperature is then increased to 180 ° C. and after 1 hour the mixture is poured into 300 parts of boiling, saturated salt solution at 180 ° C. and allowed to cool for 18 hours while stirring. The precipitated sodium salt is filtered off and washed with salt water, pressed off and dried at 130.degree. Unchanged polychloronaphthaiine can be removed by leaching with hot benzene, and the remaining sodium salt can be freed from the chlorine sodium by washing it out with 350 parts of boiling water.

The product thus obtained gives a clear solution in hot water. An i; 6 0/0 solution solidifies to a gel on cooling, which, however, on stirring or shaking is liquefied.

Other salts can be prepared by adding the sulfonation product is neutralized with a suitable base or a salt. Examples of ioo parts 25 parts of a hot, aqueous iooröigen solution of sodium trichloronaphthatinsulfonat added, which in the manner shown in Example I from polychloronaphthalene with three chlorine atoms is obtained in the molecule. The whole thing is stirred well and left to cool. That Product is then ready to be stored without the risk of settling.

Example 3 50 parts of a hot, aqueous solution of sodium trichloronaphthalene sulfonate of Io 0j0 starch are mixed with zoo parts of an aqueous pulp of thioindigo in a finely divided state, which contains 25% of the pure dye. That Mixture is: Stirred thoroughly and then left to cool and can then be stored will.

Example q.

200 parts of an aqueous paste of the dye; softer- through clutch from i. 2 # 4-Dinitroaniline with 3-Naphthol 'is obtained and 25 parts of pure dye contains, are mixed with 50 parts of a hot, aqueous 100000000 solution of sodium trichloronaphthalene sulfonate, whereupon the mass is allowed to cool. Thereby a paste is obtained which is essentially free from the disadvantage of Weaning is.

Claims (1)

PAT1? NTANSPRU CII Process for the production of non-weaning, Aqueous dye pastes, characterized in that an aqueous Paste or suspension of an insoluble dye a polychloronaphthalene sulfonic acid or add a salt of the same.