Hoechst Aktiengesellschaft

Kurt Hohmann

Reinhard Mohr

Manfred Hahnke

Peter Mischke

Eberhard Mundlos

Theodor Papenfuhs

Wolfgang Teige

Rudolf Neeb

Rudolf Lowenfeld

Horst-Roland Mach

Manfred Sittig

Gerd Pelster

Norbert Kollodzeiski

Eckhard Schwab

Sierling Ong

Cellulosic textiles are printed or dyed with multiple hook reactive dyes without fabric hand harshening on using a reactive dye preparation containing 0.5 to 10% by weight of a surfactant and 0 to 10% by weight of an antifoaming agent.

Prevention of fabric hand harshening on printing of dyeing cellulosic

Process for producing concentrated aqueous solutions of anionic azo dyes

Liquid formulations of mixtures of cationic dyes frequently have a very short storage life. As a consequence, these formulations give rise to customer complaints concerning incorrect dyeing strengths and hues and concerning isoluble constituents. It has now been found according to the invention that powder formulations and in particular liquid formulations of cationic dyes or of mixtures of these dyes can be stabilized by adding selected oxidizing agents.

Storable formulations of cationic dyes with oxidizing agent as stabilizer

Dye salts of a mono- or polycationic dye where the anion conforms to a general formula (1) or (2)

Novel dye salts of cationic dyes, having thiocyanatometallate or

Improvement of a process for spin-dyeing acid-modified polymers or copolymers of acrylonitrile in which cationic quaternary dyestuffs are added to the spinning mass and spun according to the wet-spinning procedure. The improvement is characterized by using dyestuffs characterized by a migration factor M of 20 or less than 20, by a combination index K of less than 2.5 and a cation weight of more than 310. Migration factor M and combination index K are known values in the dyestuff field or can be determined. The dyestuff to be used according to the invention can belong to the most different classes of dyestuffs; they fix rapidly on the polymer, and thus they do not color, or color only to a minor extent, the coagulation, stretching and washing baths although they are soluble in water and aqueous solutions of these baths. The fibers and filaments obtained by the process of the invention have outstanding fastnesses to wet processing and, owing to the absence of dyestuff aggregates at the surface of the fiber such as occur when spin-dyeing with pigments, very good fastnesses to dry and wet rubbing. The fibers are intense, absolutely transparent and free from specks.

Process for spin-dyeing of acid-modified polymers of copolymers of

Fiber material composed of acid-modified homopolymers or copolymers of acrylonitrile (PAC fibers) which has been obtained by a wet spinning process, has not been dried and is still in a swollen condition (gel form), can be dyed advantageously and in fast colors by means of soluble dyes, the molecule of which contains several groups, namely more than one quaternary grouping and/or a strongly basic grouping carrying no charge, which exert a basic action towards the acid groups of the fiber substance. The chromophore of this colorant can belong to the category of monoazo or diazo dyes, methine, azamethine or diazamethine dyes or naphthalactam dyes. In accordance with the invention, after substantially removing the non-aqueous spinning solvent by washing, the spun material, as a moist gel, is dyed continuously or discontinuously from an aqueous dyebath; the fibers can be stretched before the dye is applied, during the dyeing process itself or immediately afterwards. By virtue of their special nature, the dyes of the type designated above, which have a strong fixing action, produce optimum fixing rates when dyeing PAC gels and, in the subsequent production stages, do not cause any noticeable soiling, as a result of dye which has bled out, on components of machines and operating baths, such as stretching or after-treatment baths. Investigations of penetration of the fiber by the dye, of the fixing rate and of the resulting fastness properties, such as fastness to wet processing, have shown no disadvantages compared with conventional dyes.

Process for dyeing, in the gel state, fiber material composed of wet

Process for spin-dyeing of acid-modified polymers of acrylonitrile by

Chlorozincate salts of thiazolium azo compounds are prepared by reacting thiazolium azo compounds with an dialkylsulfate having from 1 to 4 carbon atoms in the alkyl radicals, which process comprises carrying out the reaction in an aqueous medium at a temperature of from about 10.degree. to 50.degree. C. in the presence of a zinc compound capable of binding acid, and with the use of from 1.8 to 2.5 mols of the dialkylsulfate, calculated on the starting azo dyestuff, at a pH not exceeding 8, preferably at 3-7. The prepared thiazolium azo compound is precipitated as chlorozincate salt, especially by means of an alkali metal chloride. According to this process, the chlorozincate salts are obtained in higher purity. A perceptible decomposition of the thiazolium azo compound does not occur. Chemicals, for example the alkylation agent and acid-binding agents need be used in a small quantity. In addition to this economy and to the less pollution of the waste water, the process has the advantage that it can be carried out with the use of a small reaction volume.

Process for the preparation of chlorozincate salts of thiazolium azo

A dyeing process has been found which enables to dye uniformly polyacrylonitrile fiber materials, by using as dyestuffs basic azo dyestuffs being non-quarternized and containing neither cationic quaternary ammonium groups nor cationic N-substituted or N-unsubstituted iminium groups, said azo dyestuffs containing on the other hand at least one unsubstituted or substituted amino group, hydrazino group, amidino group or guanidino group capable of forming salts. The very dyeing process as such is carried out according to usual processing data for dyeing polyacrylonitriles in a slightly acid medium. Especially with the use of several of these dyestuffs for polychromic dyeing, such as trichromic dyeing, special advantages are obtained, insofar that even at cut-rate dyeing periods and for preparing light color shades, there are obtained even dyes with constant color shades, when using these dyestuffs having good migrating properties.

Process for dyeing uniformly polyacrylonitrile fiber materials

It has been found that nickel-containing polyolefins can be dyed and printed in deep colors and with very good to excellent fastness properties when a thiazole-azo-(3-cyano-2,6-dihydroxypyridine) dyestuff is used.

Process for dyeing and printing nickel-containing polyolefins

New basic azo dyestuffs of the formula ##STR1## where D.sup.(+) is the radical of an aromatic or heterocyclic diazo component containing a quaternary nitrogen atom,

Quaternary basic azodyestuffs containing a propenyl amino radical

A process for the preparation of new dyestuff compositions which contain one or more basic dyestuffs in the form of dyestuff bases from the series of the triarylmethane, indoldiarylmethane, azine, oxazine, thiazine or xanthene dyestuffs or one or more basic dyestuffs of the series of the azo, anthraquinone, phthalocyanine, styryl, quinophthalone, benzoxanthene, naphthoylene-benzimidazole, naphthalimide or nitro series, carrying a primary, secondary or tertiary amino group or a guanidino or hydrazino group, as well as one or more non-ionic or slightly cationic surface-active agents and, optionally, water and/or an organic solvent miscible with water, which process comprises synthesizing the dyestuff in the surface-active agent optionally containing water and/or an organic solvent miscible with water, and then adding, if necessary, water and/or a solvent miscible with water and a further surface-active agent, this process of the invention having the advantage that an intermediate isolation, drying or grinding of the dyestuffs contained in the dyestuff compositions defined above is not necessary, so that the dyestuffs need not be introduced as substance into the surface-active agent and the solvent in a process wherein compositions of this type are prepared by a usual mixing, kneading or melting process; moreover, higher dyestuff yields are obtained in the dyestuff synthesis, and it allows to prepare dyestuff compositions from dyestuffs which are difficult to be isolated in substance after synthesis and often precipitate as oily or smeary products. The dyestuff compositions obtained according to the process of the invention, which are pastes or liquids, have a high stability upon storage. After being diluted with an aqueous solution of an amount at least equivalent to the dyestuff of an inorganic or organic acid, as well as, optionally, after the addition of dyeing and/or printing auxiliaries, the novel dyestuff compositions are suitable for dyeing or printing textile material containing acid groups.

Process for the preparation of dyestuff compositions

A process for the direct preparation of pure thiazolazo compounds had been found with the use of a 2-aminothiazole as diazo or azo component in a coupling process wherein the 2-aminothiazole used therein is subjected to the usual coupling reaction, if used as diazocomponent after diazotation, without intermediate isolation after its preparation in known manner. This process avoids the preparation of the 2-aminothiazoles as starting compounds in its solid form and the expensive purification of these instable compounds and yields now very pure azo products.

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Neu-Isenburg, Germany

Kurt Hohmann