WO2013023979A1 - Method for dyeing substrates containing collagen fibre - Google Patents

Abstract

A method for dyeing substrates containing collagen fibre and treated with at least one compound containing carbamoylsulphonate groups, the method being characterized in that subsequent dyeing of the collagen fibre substrate thus treated takes place with at least one anionic dye, the compounds in the component that contain carbamoylsulphonate groups being a reaction product of at least one organic polyisocyanate and at least one bisulphite and/or disulphite, characterized in that the organic polyisocyanate has a molecular weight of less than 400 g/mol and contains NCO groups bonded to aliphatic or cycloaliphatic structures.

Description

 Process for dyeing collagen fiber-containing substrates

The invention relates to a process for dyeing a collagen fiber-containing substrate treated with a carbamoylsulfonate group-containing compound.

The coloring of chrome-tanned leathers has long been known, for example from US-A-5085167. The coloring of chromium-free tanned leathers, for example of vegetable or glutardialdehyde tanned leathers (wet white), is already known. However, it is disadvantageous that vegetable or glutardialdehyde tanned leather still have problems in terms of their brilliance, Durchstärbbarkeit, levity and uniform coloring of meat side and grain side. Furthermore, it is important that in addition also the requirements placed on the respective leather article regarding the optical and haptic properties such as softness, grain smoothness, fullness are met.

According to WO2010 / 130311, an alternative tanning process with organic, reactive tanning agents based on dichlorotriazine compounds, which are obtained by reacting amino-functional aromatic sulfonic acids with trichlorotriazine, has also been proposed. Even if less yellow wet white is already obtained, the above-mentioned properties, the wet whites and the subsequent coloring are still in need of improvement.

The object of the present invention was to find a method by which chromium-free tanned collagen fiber-containing substrates, in particular leather or fur skins, can be dyed with satisfactory results and have improvements in the abovementioned properties.

Surprisingly, it has now been found that this object can be achieved for collagen fiber-containing substrates which have been treated with compounds containing carbamoylsulfonate groups and which, after dyeing with anionic dyes, have distinct advantages of dyeing in the abovementioned properties in comparison to other tanned leathers. The invention therefore relates to a process for dyeing collagen fiber-containing substrates treated with at least one carbamoylsulfonate-containing compound, which comprises subsequently dyeing the thus treated collagen fiber-containing substrate with at least one anionic dye, wherein the carbamoylsulfonate-containing compound comprises a reaction product at least one organic polyisocyanate and at least one bisulfite and / or disulfite, characterized in that the organic polyisocyanate has a molecular weight of less than 400 g / mol with NCO groups bound to aliphatics or cycloaliphatic, in particular 1, 4-diisocyanatobutane, 1, 6-diisocyanatohexane (HDI), 1, 5-diisocyanato-2,2-dimethylpentane, 2,2,4- and 2,4,4-trimethyl-1,6-diisocyanatohexane (TMHI), 1,3- and 1,4-diisocyanatohexane, 1,3- and 1,4-diisocyanato-cyclohexane (CHDI) as well as any desired mixtures of these isomers, 1-isocyanato-2-isocyanatomethyl-cyclopentane, 1,2- , 1,3- and 1,4-bis (isocyanatomethyl) -cyclohexane and any desired mixtures of isomers, 1,2-, 1,3- and 1,4-bis (isocyanatoethyl) -cyclohexane and any desired mixtures of these isomers, 1, 2-, 1,3- and 1,4-bis (isocyanato-n-propyl) -cyclohexane and any mixtures of these isomers, 1-isocyanatopropyl-4-isocyanatomethyl-cyclohexane and isomers, l-isocyanato-3,3,5- trimethyl-5-isocyanatomethylcyclohexane (IPDI), 1-isocyanato-1-methyl-4-isocyanatomethylcyclohexane (IMCI), 2,4'- and 4,4'-diisocyanatodicyclohexylmethane (H ₁₂ MDI) and isomers, Dimeryl diisocyanate (DDI), bis (isocyanatomethyl) bicyclo [2.2.1heptane (NBDI), bis (isocyanatomethyl) tricyclo [5.2.1.0 ² ' ⁶ ] decane (TCDDI) and isomers and any mixtures of such diisocyanates and xylylene diisocyanates formulas

EP-A 0 690 135, WO98 / 38340 and EP-A 0 814 168 already describe carbamoylsulfonate-containing compounds as tanning agents which are substantially inert to the reaction with water. An aqueous dispersion having a stability sufficient for use in the tanning process is obtained. However, this process has two serious disadvantages:

The reaction of isocyanate with polyether alcohol must be carried out with the exclusion of water and preferably without viscosity-lowering solvents and therefore requires technically high-quality and expensive hardware and an additional synthesis step.

The reaction of the polyether alcohol with the isocyanate consumes part of the isocyanate functions and thus reduces the tanning effect of the product.

Also known from EP-A-1647563 are aqueous compositions containing at least one compound containing carbamoylsulfonate groups and at least one alcohol alkoxylate. Among collagen fiber-containing substrates for the treatment, in particular tanning, with a carbamoylsulfonate group-containing compound according to the invention is in particular the common animal derived raw materials, in particular hides and skins, for example, cattle hides and files of cattle, veal, buffalo, hides and skins of pig, sheep, goat, reindeer, deer, kangaroo, hides and skins of other small animals such as sable, fox, Rabbits, hides of reptiles (eg snakes), fish or birds, as well as split skins (for example, crevices, meat split, column with hair) and pre-tanned semifinished products (eg wet white) understood.

In this case, the collagen fiber-containing substrates may be associated with keratinic constituents or be free from keratinic constituents. By keratinic constituents animal hairs are to be understood in particular. Collagen fiber-containing substrates with associated keratinic constituents are in particular hides and skins in which the keratinic constituents, in particular the animal hairs, are not removed during the work in the water workshop, during the tanning and the subsequent steps in the retanning and completion to the ready-to-use material and not damaged but remain firmly connected to the surface support of the collagen fiber-containing substrate, the so-called dermis. The tanned hides and skins made from this raw material, in which the hair is intact and firmly attached to the dermis, are summarized below under the term fur skins. These also have disadvantages in the dyeing.

Collagen fiber-containing substrates without keratinic constituents are in particular hides and skins in which the keratinic constituents, in particular animal hairs, were removed in the liming mill in the water workshop and which were used as uncleaved leaves or after splitting as crevices, meat gaps or middle gaps and then during tanning and in the subsequent steps in the retanning and, if necessary, dressing are processed to ready-to-use material. The tanned hides and skins made of this raw material, in which the hair was removed in the water workshop in the so-called limber, are summarized below under the term leather. These also have disadvantages in the dyeing.

Preferred collagen fiber-containing substrates are preferably leather and fur skins, which in particular have a chromium content of less than 1000 ppm, in particular less than 500 ppm, based on the substrate. Carbamoylsulfonate-containing compounds (component a) are understood as meaning those having the following structural unit:

-NH-CO-SO ₃ K where K ^{+ is} a cation equivalent.

Preference is given to organic polyisocyanates having an NCO functionality of 1.8 to 2.5.

Preference is given to using the above diisocyanates. However, it is also possible to use monofunctional aliphatic isocyanates, such as, for example, butyl isocyanate, hexyl isocyanate, cyclohexyl isocyanate, stearyl isocyanate or dodecyl isocyanate and / or polyisocyanates having an average NCO functionality of 2.2 to 4.2.

The higher-functional polyisocyanates are preferably composed of trimeric 1,6-diisocyanatohexane, trimeric 1,2-, 1,3- or 1,4-bis (isocyanatomethyl) cyclohexane, trimeric 1,2-, 1,3- or 1,4-bis (isocyanatoethyl) cyclohexane, trimeric 1,2-, 1,3- or 1,4-bis (isocyanato-n-propyl) -cyclohexane, trimeric 1-isocyanatopropyl-4-isocyanatomethyl-cyclohexane and isomers or trimeric 1-isocyanato-3,3,5-trimethyl-5-isocyanatomethylcyclohexane and optionally dimeric 1,6-diisocyanatohexane, dimeric 1,2-, 1,3- or 1,4-bis (isocyanatomethyl) cyclohexane, dimeric 1,2-, 1,3- or 1,4-bis (isocyanatoethyl) cyclohexane, dimeric 1,2-, 1,3- or 1,4-bis (isocyanato-n-propyl) -cyclohexane, dimeric 1 Isocyanatopropyl-4-isocyanatomethylcyclohexane and isomers, or dimeric l-isocyanato-3,3,5-trimethyl-5-isocyanatomethyl-cyclohexane and the corresponding higher homologs existing isocyanurate groups and optionally uretdione polyisocyanate having a m NCO content of 19 to 24% by weight, as is known per se by catalytic trimerization and isocyanurate formation of 1, 6-diisocyanatohexane, 1,2-, 1,3- or 1, 4-bis (isocyanatomethyl ) cyclohexane, 1,2-, 1,3- or 1,4-bis (isocyanatoethyl) cyclohexane, 1,2-, 1,3- or 1,4-bis (isocyanato-n-propyl) -cyclohexane, 1 Isocyanatopropyl-4-isocyanatomethylcyclohexane and isomers, or from isocyanato-3,3,5-trimethyl-5-isocyanatomethylcyclohexane, and which preferably has an (average) NCO functionality of from 3.2 to 4.2 exhibit. The use of monofunctional and of more than difunctional isocyanates in both cases is preferably limited to amounts of not more than 10 mol%, based on all polyisocyanates.

However, very particular preference is given to the abovementioned aliphatic, cycloaliphatic and araliphatic diisocyanates. Particularly preferred are hexamethylene diisocyanate (HDI), diisocyanato-cyclohexane, 1,2-, 1,3- and 1,4-bis (isocyanatomethyl) cyclohexane and any desired mixtures of isomers, 1,2-, 1,3- and 1, 4 bis (isocyanatoethyl) cyclohexane and any mixtures of these isomers, 1,2-, 1,3- and 1,4-bis (isocyanato-n-propyl) -cyclohexane and any mixtures of these isomers, 2,4'- and 4,4'-diisocyanato-dicyclohexylmethane, 1-isocyanatopropyl-4 isocyanatomethylcyclohexane and isomers and 1-isocyanato-3,3,5-trimethyl-5-isocyanatomethylcyclohexane (IPDI). Hexamethylene diisocyanate (HDI), 1,2-, 1,3- and 1,4-bis (isocyanatomethyl) -cyclohexane and mixtures of these isomers are especially preferred from this latter group. Suitable bisulfites and / or disulfites are preferably their alkali metal or ammonium salts, in particular the sodium salts of sulfurous or disulfurous acid, ie sodium hydrogen sulfite (NaHSC> 3) or sodium disulfite (Na2S2Ü5).

The other alkali metal and ammonium salts of these acids, namely potassium bisulfite, potassium bisulfite, lithium bisulfite, lithium disulfite, ammonium bisulfite, ammonium bisulfite and simple tetraalkylammonium salts of these acids, such as tetramethylammonium bisulfite, tetraethylammonium bisulfite, etc., may also be used to advantage Solutions with solids contents of 5 to 40% by weight used.

In a preferred embodiment of the invention, the carbamoylsulfonate-containing compounds based on aliphatic polyisocyanates such as hexamethylene diisocyanate, isophorone diisocyanate, bis (isocyanato) cyclohexane, 1,2-, 1,3- and 1,4-bis (isocyanatomethyl) - cyclohexane and any mixtures of Isomers, 1,2-, 1,3- and 1,4-bis (isocyanatoethyl) cyclohexane and any mixtures of these isomers, 1,2-, 1,3- and 1,4-bis (isocyanato-n-propyl) - Cyclohexane and any mixtures of these isomers, l-isocyanatopropyl-4-isocyanatomethyl cyclohexane and isomers, 2,4 'and 4,4'-diisocyanato-dicyclohexylmethane or nonyl triisocyanate and mixtures thereof, but especially hexamethylene diisocyanate 1,2-, 1,3 - And 1,4-bis (isocyanatomethyl) cyclohexane and any mixtures of isomers, 1,2-, 1,3- and 1,4-bis (isocyanatoethyl) cyclohexane and any mixtures of these isomers, 1,2-, 1 , 3- and 1,4-bis (isocyanato-n-propyl) -cyclohexane and any mixtures of these isomers and / or Isophorone diisocyanate, particularly preferably hexamethylene diisocyanate, isophorone diisocyanate, 1,3-bis (isocyanatomethyl) cyclohexane and 2,4'- and 4,4'-diisocyanato-dicyclohexylmethane. For this last-mentioned group, the carbamoylsulfonate-containing compounds are particularly preferably based on hexamethylene diisocyanate (HDI), 1,2-, 1,3- and 1,4-bis (isocyanatomethyl) -cyclohexane and mixtures of these isomers.

Tanner form The carbamoylsulfonate group-containing compound used for tanning can be used in liquid form, for example as aqueous compositions, or as a particulate solid.

In the case of aqueous compositions, these may be present, for example, as a solution or suspension. A solution is preferred. Preferably, the dry residue of the aqueous composition, ie the total concentration of the ingredients of the aqueous composition, is preferably from 25 to 50%. In particular, a total concentration of the aqueous composition of from 30 to 40% is advantageous, with the proportion of the carbamoylsulfonate group-containing compound in the composition being particularly advantageously from 28 to 35%.

When other additives are used, it is preferred that the proportion of the carbamoylsulfonate group-containing compound decreases in the corresponding ratio according to the proportions of the further additional component, so that the total concentration of the solids in the aqueous solution is preferably not more than 50%.

Also preferably, the carbamoylsulfonate-containing compound is used as a particulate solid, which preferably has a melting point of greater than 20 ° C, preferably greater than 60 ° C, in particular greater than 100 ° C.

By "particulate" is meant, in particular, a material having an average particle size of 0.1 μm to 1000 μm, preferably 1 to 800 μm, in particular 50 to 300 μm, the mean being based on the mass (weight average) of all particles The mean particle size can be determined, for example, microscopically, preferably the solid material is in the form of powder or granules, Preferably, the particulate solid material has a residual moisture content of 0 to 10% by weight. in particular from 0 to 5% by weight, particularly preferably 0 to 2% by weight, based on the material The particulate solid material is generally based on any, preferably a spherical or spherical shape-like or derived particle structure Agglomerates of particles of the mentioned forms in the range of the specified particle size in Question: The particulate solid material contains 1 to 100%, preferably 10 to 100%, more preferably 25 to 100%) of compounds containing carbamoylsulfonate groups.

Very particular preference is given to compounds containing carbamoylsulfonate groups and their preparations using component d) and optionally component e), which contain no emulsifier and which have a pH of less than 4.5, based on a 35% solution in Water. Particularly preferred is the use of carbamoylsulfonate-containing compounds for tanning in the form of particulate solids.

Emulsifier The carbamoylsulfonate group-containing compound used for tanning may contain one or more emulsifiers of component c) or contain no emulsifier. Preferred carbamoylsulfonate-containing compounds contain no emulsifier. Suitable emulsifiers are, for example, cationic, anionic, amphoteric and nonionic surfactants, which are preferably capable of reducing the interfacial tension between an organic and an aqueous phase, so that an oil-in-water emulsion can form.

Preferred cationic emulsifiers are quaternary ammonium compounds, for example cetyltrimethylammonium bromide or benzyllauryldimethylammonium chloride.

 Preferred anionic emulsifiers are soaps, metal soaps, organic soaps such as mono-, di- or triethanolamine oleate, stearate, diethylethanolamine oleate, stearate or 2-amino-2-methylpropane-1-ol stearate, sulfurized compounds such as sodium dodecyl sulfate or Turkish red oil and sulfonated compounds such as sodium cetylsulfonate ,

Preferred amphoteric emulsifiers are phosphatides such as lecithins, various proteins such as gelatin or casein and the actual amphoteric surfactants.

Preferred nonionic emulsifiers are fatty alcohols such as lauryl, cetyl, stearyl or palmityl alcohol, partial fatty acid esters of polyhydric alcohols with saturated fatty acids such as glycerol monostearate, pentaerythritol monostearate, ethylene glycol monostearate, or

Propylene glycol monostearate, partial fatty acid esters of polyhydric alcohols with unsaturated fatty acids such as glycerol monooleate, pentaerythritol monooleate, furthermore polyoxyethylene esters of fatty acids such as polyoxyethylene stearate, polymerization products of ethylene oxide and propylene oxide with fatty alcohols such as fatty alcohol polyglycol ethers or fatty acids such as fatty acid ethoxylates.

Particularly preferred nonionic emulsifiers are at least one nonionic, ester group-containing, alkoxylated polyol having an HLB value of at least 13 (c1) and / or an alkyl glycoside (c2) and / or a nonionic ester group-free alkoxylated alcohol (c3).

Component cl)

The preferred nonionic, ester group-containing, alkoxylated polyols of component cl) have an HLB value of 13 to 19, in particular 14 to 18, wherein the HLB value is determined by the method according to Griffin, W. C: Classification of surface active agents by HLB, J. Soc. Cosmet. Chem. 1, 1949. In addition, preferred compounds of component (c1) have a water solubility at 20 ° C. of at least 10 g per liter, in particular at least 20 g per liter.

Suitable compounds of component c1) are those which are obtainable in a manner known per se from polyols by alkoxylation and partial esterification of the hydroxyl groups with a carboxylic acid. Suitable starting polyols, for example, polyhydric (cyclo) aliphatic alcohols such as glycerol, trimethylolpropane, pentaerythritol, dipentaerythritol, derived from mono- or polysaccharides polyols, preferably the molecular weight of 92 to 2000 are used as starter molecules. Particularly preferred starter alcohols are polyols having from 3 to 10 hydroxyl groups, in particular glycerol, and those having a sorbitan skeleton, in particular 1,4- or 1,5-sorbitan, preferably 1,4-sorbitan.

Preferred compounds containing carbamoylsulfonate groups are characterized in that the compound of component c1) used is the reaction product of a polyol with at least one alkylene oxide having 2 to 6 carbon atoms, preferably in an amount of 10 to 60 molar equivalents, based on the Polyol and subsequent reaction with at least one carboxylic acid having 6 to 30 carbon atoms. The polyol used is preferably a polyol selected from the group consisting of glycerol, trimethylolpropane, pentaerythritol, dipentaerythritol, and mono- and polysaccharide-derived polyols, in particular sorbitol and polyols having a sorbitan skeleton.

The compounds of component cl) are particularly preferably partially esterified sorbitan alkoxylates whose hydroxyl groups are esterified before or preferably after the alkoxylation with carboxylic acids having a chain length of 6 to 30 carbon atoms, each hydroxyl group of the base polyol having an independent number of Have alkoxy units and per sorbitan unit on average 10 to 60 alkoxy units are present. The preferred esterified sorbitan alkoxylates have a random distribution of the alkoxy groups.

Preference is given to partially esterified alkoxylated sorbitan derivatives by reaction of a sorbitan of the formula X- (OH): in which

X is a sorbitan radical, in particular a 1,4-sorbitan radical and m is the number 4

10 to 60 equivalents, per mole of sorbitan, preferably 10 to 40, particularly preferably 10 to 30 and very particularly preferably 15 to 25 equivalents of identical or different C2-C6-alkylene oxides, in particular C2 and / or C3-alkylene oxides, preferably ethylene oxide and with

1 to 3, preferably 0.8 to 1.2 equivalents, based on the sorbitan, of an aliphatic, optionally unsaturated carboxylic acid, preferably having a chain length of 6 to 30 carbon atoms, which is unsubstituted or substituted by hydroxy groups, preferably straight-chain, in made in any order. The reaction with the alkylene oxide is preferably carried out first, followed by the reaction with the carboxylic acid.

Preferred are sorbitan polyoxyethylene monoesters, which are alkoxylated with 10-60 moles of ethylene oxide units per sorbitan unit, and preferably have a 1,4-sorbitan skeleton.

These preferably correspond to the following structural formulas in which

R is an optionally substituted by hydroxyl groups alkyl or alkenyl radical of

 Carboxylic acid is and m, n, p and q are independent, are statistical values and each represents a number from 0 to 60, with the proviso that the sum of the number of oxyethylene

Units m + n + p + q is from 10 to 60, preferably 18 to 22, especially 20.

Also suitable are corresponding alkoxylated sorbitan diesters and mixtures thereof.

Furthermore, alkoxylated sorbitan esters are suitable in which a hydroxyl group of the sorbitan unit, in particular in the formulas given above, is esterified directly with the carboxylic acid, ie in which there is no alkylene oxide unit between the sorbitan unit and the carboxylic acid residue and the three are not acylated Hydroxyl groups are etherified with a correspondingly higher number of alkylene oxide units. Such compounds are obtainable, for example, by first esterifying the sorbitan with a carboxylic acid and subsequently alkoxylating the resulting product, consisting of a mixture of the isomeric monoesters, which may also contain mixtures of the isomeric diesters in the presence of an excess of carboxylic acid. The alkylene oxide used for the alkoxylation of sorbitan is preferably selected from the group consisting of ethylene oxide, propylene oxide and butylene oxide. It is also possible that the sorbitan is reacted with various of said alkylene oxides, for example ethylene oxide and propylene oxide, whereby sorbitan-alkoxylates can be obtained, each comprising blocks of several units of an alkylene oxide, for example ethylene oxide, in addition to blocks of several units of another Alkylene oxide, for example propylene oxide having. The sorbitan alkoxylates particularly preferably contain ethylene oxide (EO) units, preferably exclusively. In such a case, the alkylene oxide used is particularly preferably ethylene oxide.

Furthermore, it is possible in the reaction of a sorbitan with various of said alkylene oxides, e.g. To obtain ethylene oxide and propylene oxide, sorbitan alkoxylates in which the incorporation of the various alkylene oxides is carried out statistically. The amounts of alkylene oxide used are preferably 10 to 60 moles of alkylene oxide per mole of sorbitan, preferably 10 to 40 moles, more preferably 10 to 30 moles and most preferably 15 to 25 moles. Very preferred alkylene oxide is ethylene oxide. The carboxylic acids suitable for the esterification of the starting polyol, especially the sorbitan alkoxylate, are preferably saturated or unsaturated and linear or branched and may optionally be substituted by hydroxyl groups. The following carboxylic acids may be mentioned as examples: hexanoic acid, heptanoic acid, octanoic acid, nonanoic acid, decanoic acid, undecanoic acid, dodecanoic acid, tridecanoic acid, tetradecanoic acid, pentadecanoic acid, hexadecanoic acid, heptadecanoic acid, octadecanoic acid, nonadecanoic acid, eicosanoic acid, octadecenoic acid (oleic acid), undecenoic acid. Decanoic acid, undecanoic acid, dodecanoic acid (lauric acid), tetradecanoic acid, hexadecanoic acid (palmitic acid), octadecanoic acid (stearic acid) and ricinoleic acid are particularly preferred. Very particular preference is given to dodecanoic acid (lauric acid), hexadecanoic acid (palmitic acid) and octadecanoic acid (stearic acid) and octadecenoic acid (oleic acid). As compounds of component cl) it is possible to use, for example, commercially available products, such as, for example, sorbitan polyoxyethylene (20) monolaurate (for example Polysorbat® 20 or Tween® 20 (Croda Oleochemicals) or Eumulgin® SML 20 (Cognis)), sorbitan polyoxyethylene (20) monopalmitate (for example Polysorbate 40 or Tween® 40 (Croda Oleochemicals)), sorbitan polyoxyethylene (20) monostearate (for example polysorbate 60 or Tween® 60 (Croda Oleochemicals) or Eumulgin® SMS 20 (Cognis)), sorbitan polyoxyethylene (20 ) monooleate (for example Polysorbate 80 or Tween® 80 (Croda Oleochemicals)).

Further preferred compounds of component cl) are, for example, alkoxylates of mono- and polyglycerol esters. The preparation of such alkoxylated (poly) glycerol esters is carried out either by alkoxylation of glycerol or a polyglycerol and subsequent esterification with a Fatty acid or by esterification of glycerol or polyglycerol with a fatty acid and subsequent alkoxylation. Particularly suitable for the compositions according to the invention are alkoxylates of mono- and polyglycerol esters which have an HLB value of at least 13 and preferably have a water solubility at 20 ° C. of more than 10 g per liter. Also suitable are alkoxylated glycerol esters or polyglycerol esters which have been esterified with more than one carboxylic acid. Particularly preferred are alkoxylated monoglycerol monoesters.

Suitable for alkoxylation are C 2 to C 6 -alkylene oxides, more preferably ethylene oxide. Preferred is an alkoxylation with 10 to 100 alkylene oxide units, in particular with 20 to 60 alkylene oxide units. The hydroxyl groups of glycerol or of polyglycerol have, independently of one another, on average, a different number of alkylene oxide units.

For example, be particularly suitable alkoxylates of mono- and polyglycerol esters. called: glycerol monostearate ethoxylates with an average of 15 to 30, in particular with an average of 20 EO units, glycerol monooleate ethoxylates with 20 to 40 EO units, diglycerol monostearate with 20 to 40 EO units, polyglycerol monostearate with 20 to 40 EO units Units, castor oil alkoxylates and hydrogenated castor oil alkoxylates, short (hydrogenated) castor oil alkoxylates. The latter are products which are obtainable by alkoxylation of castor oil or hydrogenated castor oil with alkylene oxides, in particular ethylene oxide and propylene oxide, preferred are those containing from 20 to 100 alkylene oxide units per (hydrogenated) castor oil unit, preferably from 20 to 60 Have ethylene oxide units per (hydrogenated) castor oil unit. Corresponding glycerol-based compounds of the components cl) are likewise available as commercial products, for example glycerol monostearate ethoxylate having on average 20 EO units as Cutina® E 24 (Cognis), hydrogenated castor oil ethoxylate having on average 40 EO units as Eumulgin® HRE 40 (Cognis).

Component c2) Preferred compounds of component c2) are, for example, alkylmonoglycosides, alkyldiglycosides, alkyltriglycosides and higher homologs, generally referred to herein as alkylglycosides, in particular monoglucosides, diglucosides, triglucosides or higher homologs and mixtures thereof, the hydroxyl groups of which are partially denoted by C _Ö -C ig-alkyl groups are substituted. Preferably, mixtures of mono-, di-, and higher homologues with Triglucosiden C _Ö CI _S - alkyl groups and a degree of polymerization (DP) of 1 to 5. Especially preferred are alkyl glucosides, the alkyl groups of a chain length of 6 to 18 carbon atoms , in particular 6 to 12 C atoms. Also preferred are alkylglucosides whose alkyl groups have a chain length distribution or represent mixtures of alkylglucosides with different alkyl chains. Alkyl glycosides are preferably substances consisting of a single ring of a sugar or a chain of rings of a sugar linked together with glycosidic linkages, the last ring of the glycosidic chain being acetalated with an alcohol. Alkyl glycosides have the following general formula H- (G) _w -O-R 'where

G represents a glycosidic unit,

R 'represents the alkyl radical of an alcohol used to form the glycosidic acetal, and w represents the average degree of polymerization, i. H. the number of linked glycosidic units is and stands for a number from 1 to 5.

Suitable are alkyl glycosides in which w is a number from 1 to 5 and R 'is the radical of a linear or branched aliphatic alcohol having 6 to 30 carbon atoms. These products are known per se and commercially available. The value w can be influenced in the synthesis by adjusting the molar ratio of alcohol to saccharide accordingly. By increasing this ratio, alkyl glycosides having a lower average value of w are obtained. Conversely, a higher degree of polymerization is achieved by a low molar ratio of alcohol to saccharide. where R 'is an alkyl radical and

The compounds are usually present as isomer mixtures. especially the

 Carbon atoms (glycosidic C atoms) are present as mixtures of the stereoisomers.

Depending on the molar ratio of the starting materials and depending on the process conditions, the preferred alkyl polyglucosides are mixtures of alkyl monoglucoside, alkyldiglucoside and alkyl triglucoside and optionally alkyl oligoglucoside, which may also contain (poly) glucoses and small amounts of the free alcohol ROH.

The preparation of alkyl polyglucosides is possible, for example, by a direct synthesis starting from sugar with an excess of one or more alcohols. In an alternative method of synthesis, one starts with starch which is first reacted with lower alcohols (e.g., methanol, ethanol, butanol) in the presence of an acidic catalyst to form an alkylglucoside having a short chain glycosidic group (e.g., methyl, ethyl, butyl). This intermediate is then reacted under vacuum with the long-chain alcohol R'-OH in the presence of an acid as catalyst by Umacetalisierung, wherein the equilibrium by distilling off the lower alcohol is shifted. For example, the preparation of alkyl glucosides is described in WO90 / 001489, US 5576425, DE 69824366 or in a publication by M. Biermann (Henkel KGaA), K. Schmid, P. Schulz in Starch - Stärke, vol. 45 (8), p. 281-288 (1993).

Particularly preferred alkylglucosides are, in particular, hexylglucoside, octylglucoside, decylglucoside, undecylglucoside, and dodecylglucoside and also their homologs, and the mixture of alkylmono-, di-, tri-, and optionally polyglucoside and mixtures from this series.

Also suitable are alkyl glycosides whose sugar moiety is composed of various sugar units. However, alkyl glycosides which are composed exclusively of glucose units are particularly preferred. The compounds of component c2) are available as commercial products: for example, a Cg-Cio-alkylpolyglucoside having a degree of polymerization (DP) of 1.6 under the trade name Glucopon® 215 CS UP (Cognis) is available. A Ci2-Ci ₆ alkyl polyglucoside with a degree of polymerization DP of 1.4 for example is available under the trade name Glucopon® 600 CS UP (Cognis). Component c3)

As preferred nonionic, ester group-free alcohol alkoxylates of component c3) polyether alcohols are suitable, which are accessible in a conventional manner by alkoxylation of suitable starter molecules. Such are known for example from EP-A-1647563. For the preparation of the polyether alcohols, any mono- or polyhydric alcohols of molecular weight 88 to 438 can be used as starter molecules.

Particularly preferred are alkoxylates of aliphatic alcohols having a chain length of 5 to 30 carbon atoms and 1-25 alkoxy units. Preference is given to using linear or branched, saturated or unsaturated alcohol alkoxylates which are obtained by reacting at least one alcohol ROH with n moles of at least one alkylene oxide per mole of alcohol ROH, where R is an alkyl radical having 5 to 30 carbon atoms, having a main chain with 4 to 29 Having carbon atoms branched in the middle of the chain with at least one C \ -C \ Q- alkyl radical; the alkylene oxide has 2 to 6 carbon atoms and the n is a value of 1 to 25.

For the purposes of the present invention, chain center means those carbon atoms of the main chain, ie the longest alkyl chain of the radical R, beginning with the carbon atom C # 2, where the numbering starts from the carbon atom (C # 1) which is directly attached to the carbon atom Rest R adjacent oxygen atom is bound, and ending with the carbon atom ω, which is the terminal carbon atom of the main chain, wherein C # 2 and the carbon atom ω-2 are included. This means that at least one of the carbon atoms C # 2, C # 3,... To Ο _ω _2 of the main chain of the radical R is substituted by a C 1 to C _j 0 -alkyl radical. This is preferred

Carbon atom C # 2 of the main chain of the radical R substituted with a C \ - to C _j Q-alkyl radical.

In addition, it is also possible that one or more carbon atoms in the middle of the chain are substituted with two C 1 to C 4 alkyl radicals, that is, one or more carbon atoms in the middle of the chain are quaternary carbon atoms.

Particularly preferred is a mixture of alcohol alkoxylates based on 1 to 3 different alcohols ROH, more preferably on 1 or 2 different alcohols ROH. In this case, the number of carbon atoms of the radical R may be different and / or the type of branching. Preferably, the main chain of the alcohols ROH has 1 to 4 branches, provided that the chain length allows more than one branch in the middle of the chain, more preferably 1 to 3, most preferably 2 or 3. These branches are generally independently 1 to 10 carbon atoms, preferably 1 to 6, more preferably 1 to 3 carbon atoms. Accordingly, particularly preferred branches are methyl, ethyl, n-propyl or iso-propyl groups. The radical R of the alcohol ROH preferably has 5 to 30 carbon atoms. Since the group R preferably has at least one branch with at least one carbon atom, the main chain comprises 4 to 29 carbon atoms. Preferably, the radical R has from 6 to 25 carbon atoms, more preferably from 10 to 20. That is, the main chain preferably has 5 to 24 carbon atoms, more preferably 9 to 19. Most preferably, the main chain has 9 to 15 carbon atoms and the others Carbon atoms of the radical R are distributed over one or more branches.

Preferred linear alcohols ROH are, for example, octyl alcohol, nonyl alcohol, decyl alcohol, undecyl alcohol, dodecyl alcohol, tridecyl alcohol, tetradecyl alcohol, pentadecyl alcohol, hexadecyl alcohol, octadecyl alcohol, octadecenyl alcohol or hexadecenyl alcohol and their technical mixtures.

The alkylene oxide reacted with the branched alcohols ROH to the alcohol alkoxylates used is preferably selected from the group consisting of ethylene oxide, propylene oxide and butylene oxide. It is also possible that a single alcohol ROH with various of said alkylene oxides, e.g. Ethylene oxide and propylene oxide, whereby alcohol alkoxylates each containing blocks of several units of an alkylene oxide, e.g. Ethylene oxide, in addition to blocks of several units of another alkylene oxide, e.g. Propylene oxide. The alcohol alkoxylates used according to the invention particularly preferably comprise ethylene oxide (EO) units, that is to say that the alkylene oxide used is preferably ethylene oxide.

Furthermore, in the reaction of a single alcohol, it is possible to use ROH with various of the alkylene oxides mentioned, e.g. Ethylene oxide and propylene oxide to obtain alcohol alkoxylates in which the incorporation of the various alkylene oxides is carried out statistically. The amounts of alkylene oxide used are preferably 1 to 25 moles of alkylene oxide per mole of alcohol, preferably 1 to 20 moles, more preferably 3 to 15 moles and most preferably 5 to 12 moles.

Particularly preferred is the use of the carbamoylsulfonate-containing compound in a mixture with an emulsifier, in particular one of the component c1), c2) and / or c3), preferably the component c1) and / or c2), in particular c1).

Preferably, the carbamoylsulfonate group-containing compound is used as an aqueous composition containing

5 to 50 wt .-%, in particular 10 to 40 wt .-% of the carbamoylsulfonate groups-containing compound of component a) and 0.05 to 5 wt .-%, in particular 0.1 to 2 wt .-% of component c), in particular component cl), each based on the composition.

Other additives

The carbamoylsulfonate-containing compound may, in addition to the preferred emulsifiers and other additives such as carboxylic acids of component d) or salts thereof, contain or do not contain.

Component d)

Suitable compounds of component d) are, in particular, monocarboxylic or polycarboxylic acids, preferably hydroxypolycarboxylic acids. Examples which may be mentioned are: formic acid, acetic acid, oxalic acid, glyoxylic acid, malonic acid, lactic acid, tartaric acid, maleic acid, glutaric acid, phthalic acid, adipic acid, malic acid, succinic acid, citric acid, or polycarboxylic acids such as (co) - polymers of (meth) acrylic acid, maleic acid, crotonic acid or Itaconic acid or derivatives thereof with optionally further monomers such as ethene, propene, styrene, hydroxyethyl methacrylate, hydroxypropyl methacrylate, hydroxyethyl acrylate, hydroxypropyl acrylate, 4-hydroxybutyl vinyl ether, in particular those having an average molecular weight (weight average MW) of 500 to 100,000 g / mol, in particular 500 have up to 30,000 g / mol.

Particularly preferred as component d) is at least one carboxylic acid, preferably oxalic acid, succinic acid, glutaric acid or adipic acid, in particular at least one hydroxy-polycarboxylic acid, preferably citric acid, tartaric acid or lactic acid or mixtures thereof. Component e)

Preferred further additives of component e) may preferably be auxiliaries, such as fatliquoring agents, dedusting agents, organic tanning agents, component b), buffers and / or fillers, or may not be present.

Fatliquoring agents are preferably substances based on biological, mineral or synthetic oils which can be provided with hydrophilic groups in order to improve the usability in water, eg. B. by complete or partial sulfation, sulfitation, carboxylation or phosphating.

Suitable fillers are preferably inert inorganic salts and organic polymers in question, for. As sulfates such as sodium sulfate or calcium sulfate, talc, silica compounds, starch or lignosulfonates into consideration. Suitable buffers are those which can be adjusted and stabilized by addition in a sufficient amount of a pH range, in particular a pH range of 1 to 5, preferably 2.0 to 3.5. Suitable buffers for this are preferably mixtures of compounds of component d) and their salts in question. Preferred salts are in particular alkali metal salts, preferably sodium or potassium salts.

Preferred dedusting agents in the case of a solid, particulate form of the carbamoylsulfonate-containing compound include, for example, alkoxylates of aromatic compounds or polyethers or certain mono- or diesters or certain mono- or diethers. Examples which may be mentioned specifically: ethoxylates, propoxylates or mixed polyethers based on EO / PO, wherein mentioned as aromatic compounds hydroquinone or phenol-styrene, polyethylene glycol having an average molecular weight of 100 to 800, polypropylene glycol having an average molecular weight of 100 to 800, EO / PO mixed polyether having an average molecular weight of 100 to 800, monoalkyl ethers or dialkyl ethers of the abovementioned polyethers, where the alkyl radical may have 1 to 4 carbon atoms, and mono- or dialkyl esters of the abovementioned polyethers with aliphatic carboxylic acids, such as, for example, acetic acid, Propionic acid, maleic acid, succinic acid, fumaric acid, glutaric acid, adipic acid, citric acid. Dustproofing agents based on mineral oil are also suitable. Dust removing agents are preferably used in an amount of 0 to 5.0, preferably 0.05 to 2.0%, based on inventive solid material.

In a likewise preferred embodiment, the carbamoylsulfonate group-containing compound used contains less than 1% by weight of organic or inorganic tannins, preferably less than 0.1% by weight, in particular the carbamoylsulfonate-containing compound used is essentially free from organic or inorganic tannins, most preferably it is free of inorganic tannins.

In a further embodiment, the carbamoylsulfonate group-containing compound used can also be used together with organic tanning agents, in particular those of component b). Preferably contains such a composition, which is present in particular as a particulate solid

From 10 to 90% by weight, in particular from 30 to 70% by weight, of the carbamoylsulfonate group-containing compound of component a), - 10 to 90% by weight, in particular 30 to 70% by weight of component b), and

0 to 5 wt .-%, in particular 0 to 2 wt .-% water (residual moisture), in each case based on the material. Also, for such a tanning agent combination, it is preferred that it is less than 1% by weight of inorganic tanning agents, preferably less than 0.1% by weight, but substantially free of inorganic tannins, each based on the tanning agent composition.

Preparation of the Carbamoylsulfonate Group-Containing Composition The carbamoylsulfonate group-containing compound used can be prepared, for example, as an aqueous composition by mixing components a) and optionally further additives in water.

The compound of component a) can also be obtained, for example, by reacting at least one organic polyisocyanate with at least one bisulphite and / or disulphite in an organic or aqueous-organic solvent such as, for example, water / dioxane analogously to the procedure from DE102006056479-A1.

Preference is also given to a process for the preparation of carbamoylsulfonate-containing compounds in which at least one organic polyisocyanate is reacted with at least one bisulfite and / or disulfite in the presence of water and optionally in the presence of an emulsifier of component c) and optionally of component d), and optionally mixed with further additives and then optionally dried, preferably spray-dried.

method

As a raw material for the production of dyed leather and fur skins collagen fiber-containing substrates, especially animal skins and skins are used with or without hair. These are first prepared in a manner known to those skilled in the art and as usual in the water workshop. The skins and skins prepared in this way are generally converted into a tanned product by treatment with compounds containing carbamoylsulfonate groups, which preferably has a shrinkage temperature of at least 65 ° C., preferably at least 68 ° C., particularly preferably at least 70 ° C. The shrinkage temperature is determined by methods known to those skilled in the art, for example by heating the tanned intermediate by immersion in a water bath whose temperature is increased at a certain heating rate until the contraction of the material is observed. The temperature reached on contraction is read on the display of the tester (Leather Shrinkage Tester). The shrinkage temperature can also be determined by means of the differential scanning calorimetry (DSC) method known to the person skilled in the art. The entire process of producing dyed leathers and furskins involves various sub-steps, including simplifying the wet-finishing steps and the finishing of the dry leather or fur skins. The wet treatment steps again include the Water workshop, tanning and retanning. The water workshop again comprises several pretreatment steps: For the production of leather (hides and skins without hair) these are the steps soft, liming, deliming and stain, for the production of fur skins (skins and skins with hair) these are the steps dirt soft / soft, laundry and degreasing. Subsequent tanning involves the steps of tanning, in which the shrinkage temperature of the collagen-containing substrate is increased and folding is enabled. The retanning generally comprises the partial steps of the actual retanning, greasing, dyeing, optionally hydrophobing and fixing. The finished leather (crust) obtained after completion of the work in wet end are finished as usual, for example, Ausgereckt, dried and usually staked. In addition, the dry leather can optionally be provided in the usual manner in finishing with finishes or coatings to adapt the properties of the leather surface to the respective requirements for later use. The fur skins obtained after completion of the work in wet end are completed as usual, for example by drying, cleats, degreasing, combing and ironing the hair coat. If desired, the fur skins can be further treated in order to adapt the properties of the leather surface to the respective requirements for later use.

The treatment with carbamoylsulfonate group-containing compounds is generally understood as the actual tanning.

The (tanned) material treated in the process according to the invention with the carbamoylsulfonate-containing compound can therefore already be referred to as leather, the so-called wet white. With the material obtained in the tanning, you can already perform conventional mechanical treatments such as wilting or folding. For the production of a ready-to-use leather (Crust), which may optionally be finished, however, further treatment steps known per se, such as in particular retanning, are required. In the process according to the invention, after the treatment with compounds containing carbamoylsulfonate groups (tanning), further post-tanning steps preferably follow, in particular containing the steps of the actual retanning with a treatment with organic tanning agents, preferably with the component b), a dyeing, if appropriate greasing and hydrophobing, as well as a fixation. In a likewise preferred embodiment, the retanning is carried out in the presence of less than 1% by weight of inorganic tanning agents, preferably less than 0.1% by weight, based on the amount of retanning agent used, in particular the post-tanning steps are carried out in the absence of inorganic tanning agents like chrome tanning agents. The process for the tanning of collagen fiber-containing substrates, in particular hides and skins, is preferably characterized in that, after the steps of the water workshop, hides pretreated as usual are treated with a compound containing carbamoylsulfonate groups.

It is preferred that the collagen fiber-containing substrate is not pickled prior to treatment with a carbamoylsulfonate group-containing compound. Pimples are understood to mean a treatment step of the substrate to be tinted collagen fiber, in particular the hides and skins, in particular of the pollen material, in which the collagen fiber-containing substrate with the aid of strong acids and salt, preferably with a mixture containing formic acid and / or sulfuric acid in the presence of sodium chloride is treated in which the pH of the aqueous tanning liquor is set to 2 to 3.5.

It is therefore a particular advantage of the process according to the invention over known processes for producing wet white that a pimple is no longer required. Thus, the tanner can be spared an additional step and at the same time the burden of the wastewater can be avoided by a high input of salt. The treatment with a carbamoylsulfonate group-containing compound and in particular also all subsequent steps of the process according to the invention are preferably carried out in the absence of mineral or other organic reactive tanning substances other than compounds containing carbamoylsulfonate groups.

Organic reactive tannins in this context are, for example, those with aldehyde functions such as glutaric dialdehyde, glyoxal, succinic dialdehyde, adipic dialdehyde or degraded dialdehyde starch.

The organic tanning agents of component b) are not organic reactive tanning agents in the context of the invention. The invention also relates to the use of anionic dyes for dyeing collagen fiber-containing substrates, in particular tanned hides and skins, ie leather and fur skins, in the presence of carbamoylsulfonate-containing compounds and optionally organic tanning agents, preferably those of component b), but in the absence have been treated by mineral or other organic reactive tanning agents. The carbamoylsulfonate-containing compound is preferably added to the collagen fiber-containing substrates treated in the water workshop, in particular hides and skins, at a pH in the section of the substrate of from pH 5 to pH 10, preferably from pH 7 to pH 10, particularly preferably pH 8 to pH 10, and at a pH in the liquor of pH 5 to 10, preferably pH 6 to pH 9, more preferably pH 6 to pH 8 is added and allowed to penetrate for 0.1 to 8 hours, preferably 0.2 to 2 hours in the entire cross section of the substrate and then adds a fixing agent. Suitable fixatives in the tannery known bases or mixtures thereof, for example, sodium hydroxide, alkali metal carbonates, Alkalihydrogencarbonate, magnesium oxide, dolomite, tertiary amines, etc., but especially dolomite, magnesium oxide, sodium carbonate and sodium hydroxide. The fixation is preferably carried out over a period of 2 to 24 hours, preferably 4 to 12 hours at a pH in the liquor of pH 7 to pH 10, preferably from pH 7.5 to pH 9.0, particularly preferably 7, 8 to 8.8. The temperature in the fixing is preferably 15 to 60 ° C, more preferably 20 to 50 ° C, most preferably 25 to 45 ° C. The appropriately prepared collagen fiber-containing substrates, in particular the pretreated skins and skins pretreated in the water workshop, are preferably used in a commercially available tanning drum in an aqueous liquor at a temperature of 10 ° C. to 60 ° C. and a pH of 5 to 10, preferably 7 to 9, with 0.5 to 10%, preferably 1 to 4% of the carbamoylsulfonatgruppen- containing compound based on pumice weight, wherein a tanned intermediate (leather) having a shrink temperature of at least 65 ° C, preferably at least 68 ° C, especially preferably at least 70 ° C receives. The shrink temperature is determined by the methods known to those skilled in the art, for example by heating the tanned intermediate by immersion in a water bath whose temperature is raised at a certain heating rate until the contraction of the material is observed. The temperature reached on contraction is read on the display of the tester (Leather Shrinkage Tester). The shrinkage temperature can also be determined by means of the differential scanning calorimetry (DSC) method known to the person skilled in the art.

It is also possible to slow down or interrupt the tanning by acidification to pH 3 to pH 6, preferably to pH 3.5 to pH 5.5, or by addition of ammonia or a primary or secondary amino compound. This is particularly advantageous if an excessive astringency of the liquor is to be avoided and a partial inactivation of the tanning agent is desired. These additional measures are suitable for influencing the tanning process in an advantageous manner.

In the process according to the invention, it is very particularly preferred to choose a low initial pH of the liquor of from 6 to 8 for the penetration of the carbamoylsulfonate-containing compound and to fix in a pH range of from 7.8 to 8.8 and by increasing the Temperature to regulate up to 60 ° C.

The tanned intermediates obtained from the bloom material, which are also referred to as wet white due to the light color, are suitable for mechanical further processing by z. B. Wilting, folding or splitting. In addition, these intermediates are characterized by a very white, clear and light-fast intrinsic color, which is a clear advantage, for example, compared with glutardialdehyde tanned leathers, especially for the production of white leather. The so-tanned leather can be retanned by other methods, and finished with known per se operations such as dyeing, greasing and optionally water repellency soft and airy crust leather with the corresponding shades.

The actual tanning essentially serves to stabilize the hides and skins, which thereby become falzbar. The preferably subsequent retanning with organic tanning agents, in particular those of component b), completes the leather production and serves to refine and adjust the properties in order to obtain useful leathers for the respective leather articles.

When retanning, it is often useful to simultaneously make a fatliquoring of the leather and to use appropriate fatliquors. Organic tanning agents are, for example, those of component b), which often have simultaneously more or less extensive filling and softening properties, in some cases by modification in the tannin formulation, such as the addition of resin tanning agents, filling polymer tanning or plasticizing polymer tanning agents, to the dominant characteristic can be made. In principle, however, all the usual non-tanning fatliquoring agents in the process according to the invention can also be used during the retanning. The working steps of the actual retanning, dyeing and greasing are advantageously carried out in the pH range from 3.5 to 6.0, it being possible to co-use hydrophobicizing agents. It is also possible to additionally perform a pot dyeing with anionic dyes before fixation.

Preferably, the actual hydrophobing is carried out at a pH of 3.5 to 7.0, preferably 3.5 to 6. Finally, the hydrophobized leather for fixing to a pH of 2.5 to 4.0, preferably 2 , 5 to 3.5 acidified, washed and finished as usual, for example by storage on the box, stretching, vacuum drying and hanging drying and studs. If particularly high hydrophobicity values are required, aluminum salts such as basic aluminum chloride, aluminum formate, titanium or zirconium salts such as zirconium sulfate may be added during the fixing step.

The mentioned non-tanning fatliquoring agents are usually pre-emulsified in aqueous systems and usually contain emulsifiers. Furthermore, such emulsions or dispersions may sometimes contain organic solvents to promote deeper penetration and uniform distribution throughout the leather surface. When co-use of non-tanning fatliquoring in Nachgerbschritt these can be used in amounts of up to 80 wt .-%, preferably up to 40 wt .-% solids, based on the shaved weight. The weight ratio of organic tannins of component b) to non-tanning fatliquoring agents is in particular 99: 1 to 20:80, especially 95: 5 to 35:65. The tanning described above can also be carried out with the concomitant use of organic tannins of component b), wherein these can be used or not be co-used. The tanning agents of component b) can be used together with the carbamoylsulfonate group-containing compound or successively.

The tanning is followed, preferably by retanning, by treatment with organic tanning agents of component b), preferably with syntans and vegetable tanning agents. During the actual retanning, the desired leather properties are set. In turn, organic tanning agents, syntans and vegetable tanning agents are preferably used. In addition, polymeric retanning agents, for example those based on (co) polymers, as well as resin tanning agents, dyes, fatliquoring agents and proportionately hydrophobicizing agents, are advantageously used here. Preferably, these agents are used during the retanning in the usual quantities for wet white.

The advantage of the tanning process according to the invention is that pimple is no longer required, leather with a wide range of properties is obtained and the folding chips resulting from the mechanical processing do not contain any harmful compounds and can be used in many ways as raw materials, i.a. also for the production of valuable products, which in turn can be used in the leather manufacturing process. This provides a significant contribution to reducing wastes in leather production and simplifying the processing of shavings.

The wetted on the basis of Carbamoylsulfonatgruppenhaltigen compounds wet whites yield white, yellowing resistant, brilliant and colored, possibly also hydrophobized leather or fur skins whose softness is adjusted by the products used in the retanning.

For the pre-tanning of fur skins the depilation is of course no longer necessary.

For collagen fiber-containing substrates with associated keratinic constituents, in particular hides and skins with hair, the production processes to finished furskins, in which the keratinic constituents, in particular hair, are to be preserved, can be very different. By way of example, the basic production process for the production of sheepskins will be described in simplified form below: The raw material used is preferably dehydrated, in particular salted and / or air-dried, sheepskin. The treatment of the raw material is usually carried out in a reel, the amounts of the funds used are given, for example, in grams per liter of liquor or in percent by weight, based on the wet weight of the hides and skins. The method is preferably divided into the following steps, wherein the invention is not limited to this described embodiment, but includes any procedure for the treatment of fur skins with carbamoylsulfonate-containing compounds:

Water Workshop:

Step 1) Dirt switch / switch in water in the presence of softeners or detergents (surfactants),

Step 2) Deflocculation, optionally splitting the raw hides

Step 3) wash with water in the presence of detergents (surfactants) and brighteners, step 4) optionally pimples for skin disruption with water, common salt and

 Formic acid, usually in the presence of a bleach, detergent and with the addition of an electrolyte-resistant fatliquoring agent,

Tanning:

 Step 5) Tanning with carbamoylsulfonate group-containing compounds

retanning:

 Step 6a) actual retanning with organic tannins, fatliquoring

 Step 6b) Dyeing and optionally hydrophobing Step 7) Drying and finishing of the skins:

 Drain, hang-dry, condition (e.g., moist wet with water

 Sawdust), studs and bows of the leather side, combing the hair coat, then

Dry-cleaning (degreasing eg with sawdust or, if necessary, use of special closed equipment and treatment with organic solvents such as in a chemical cleaning), combing and ironing the hair coat. Any commercial raw material is suitable and the hides and skins are usually treated in a reel. Most preferably, the hides and skins are first pretreated by a soak, switch, defibering and wash and then thoroughly washed.

The inventive method can also be stirred without pimples. When working with pimples, the washed hides and skins are treated in an aqueous sodium chloride solution (e.g., 5 ° Be) with the addition of carboxylic acids at pH 2 to 4 for several hours. It is then washed and then de-pipetted and degreased by means of sodium formate, sodium bicarbonate and surface-active compounds (surfactants), the pH being gradually raised to pH 5 to 10. The pickled material is then used for tanning. When working without pimples, the washed hides and skins are used directly for tanning. It is preferred that the hides and skins are not pickled prior to treatment with a carbamoylsulfonate group-containing compound.

The progress of the tanning is advantageously followed by measuring the shrinkage temperature of the substrate. If at least a shrinkage temperature of 65 ° C, preferably of at least 68 ° C, more preferably of at least 70 ° C is reached, the pH is lowered, drained the fleet and washed the fur skins.

The (tanned) material treated in the process according to the invention with the carbamoylsulfonate-containing compound can therefore already be referred to as wet white.

The so-tanned fur skins can then in the retannage (step 6) with

 6a-1 organic tanning agents, in particular with those of component b), such as syntans, polymeric retanning agents, plasticizing polymer tanning agents,

6a-2 fatliquors and

6a-3 dyes 6b) and optionally treated with water repellents.

Reservation agents may be added prior to staining if the hair is not to be dyed as well. The dye is advantageously fixed by the addition of cationic auxiliaries after dyeing. The dyeing process according to the invention can also be used with certain furskins, preferably with sheepskins for medical purposes or for direct skin contact.

At the end of the retanning step (step 6), the liquor is preferably adjusted to a pH of from 2.5 to 4.5, preferably from 3 to 4, by addition of formic acid, and the fur is washed.

The retanned fur skins are then usually taken from the reel (step 7). It is drained and dried by hanging. Then the fur skins are dressed and, if necessary, degreased moist in the lautering barrel and dried. The meat side is ground if necessary. Finally, the hair is combed and ironed. It is also possible to treat the fur skins with tools against staining or against static charge, etc., for example, by a spray application of appropriate means.

The individual process steps are described in detail below.

For tanning the pretreated in the water workshop hides and skins with hair preferably in a coiler in an aqueous liquor with a fleet length of 300 to 1000%, based on wet weight, at a temperature of 10 ° C to 50 ° C with 0.5 to 10 %, preferably 1 to 5% of at least one compound containing carbamoylsulfonate groups, based on the wet weight of the hides and skins. This gives preferably a tanned intermediate (fur, wet white) having a shrink temperature of at least 65 ° C, preferably at least 68 ° C, more preferably at least 70 ° C. The skins and hides pretreated in the water workshop are preferably conditioned in the reel to a pH in the substrate cross section of pH 5 to pH 10, preferably pH 7 to pH 10, particularly preferably pH 8 to pH 10. Then, the carbamoylsulfonate group-containing compound at an initial pH in the substrate cross section of pH 5 to pH 10, preferably pH 7 to pH 10, more preferably pH 8 to pH 10 and an initial pH in the liquor of pH 5 to 10 , preferably pH 6 to pH 9, more preferably pH 6 to pH 8 added and allowed to penetrate for 0.1 to 8 hours, preferably 0.2 to 2 hours in the entire cross-section of the substrate and then adds a fixing agent. Suitable fixatives in the tannery known bases or mixtures thereof, for example, sodium hydroxide, alkali metal carbonates, Alkalihydrogencarbonate, magnesium oxide, dolomite, tertiary amines, etc., but especially dolomite, magnesium oxide, sodium carbonate and sodium hydroxide. The fixation is preferably carried out over a period of 2 to 24 hours, preferably 4 to 12 hours at a pH in the liquor of pH 7 to pH 10, preferably from pH 7.5 to pH 9.0, particularly preferably 7, 8 to 8.8. The temperature in the fixing is preferably 15 to 60 ° C, more preferably 20 to 50 ° C, most preferably 25 to 45 ° C. In the tanning reaction of the collagen fiber-containing substrates bisulfite is released, whereby the pH value of the liquor falls. It is particularly advantageous to maintain the pH in the above-mentioned range during tanning by addition of the fixing agent. In general, addition of the fixative in 2 to 3 portions after complete penetration is sufficient to adjust the preferred pH range. Treatment with the fixative completes the covalent attachment of the carbamoyl sulfonate group-containing compounds to the collagen fiber-containing substrate.

Dyeing is preferably carried out by treating a collagen fiber-containing substrate which has been treated with at least one carbamoylsulfonate-containing compound in an aqueous liquor containing at least one anionic dye before, during or after the actual retanning. After tanning and folding, very white wet white substrates are obtained, which can be used for the subsequent steps.

After the actual retanning preferably the pH is lowered to 3 to 4, then washed and then in the presence of fatliquoring, dyeing auxiliaries and anionic dyes, which are preferably used in diluted form, at 15 to 70 ° C and pH 3 to 4 im Stained for 1 to 3 hours, then acidified to a pH of 2.5 to 4, optionally treated with further concentrated anionic dye (pot color),

The anionic dye is preferably used in an amount of 0.05 to 5%, based on shaved weight (leather) or based on wet weight (fur skins) In the case of a pot coloration preferably 0.01 to 1.5% of anionic dye, based on Folding weight (leather) or based on wet weight (fur skins) used.

The anionic dyes can be used as aqueous solutions, suspensions or in solid form as powders or granules. These may contain other auxiliary agents, such as organic solvents, stabilizers, dyeing auxiliaries or other customary additives. Preferred anionic dyes include, for example, the following:

Acid Black 2, Acid Black 52, Acid Black 71, Acid Black 84, Acid Black 107, Acid Black 173, Acid Black 194, Acid Black 210, Acid Black 220, Acid Black 234, Acid Blue 25, Acid Blue 90, Acid Blue Acid Blue 158, Acid Blue 193, Acid Blue 284, Acid Blue 349, Acid Brown 75, Acid Brown 83, Acid Brown 161, Acid Brown 194, Acid Brown 282, Acid Brown 298, Acid Brown 311, Acid Brown 314, Acid Brown 322, Acid Brown 324, Acid Brown 349, Acid Brown 355, Acid Brown 365, Acid Brown 413, Acid Brown 414, Acid Brown 425, Acid Brown 431, Acid Brown 432, Acid Brown 434, Acid Brown 452, Acid Brown 75, Acid Brown 97, Acid Brown Mix, Acid Green 26, Acid Green 68, Acid Green 104, Acid Orange 111, Acid Orange 33, Acid Orange 61, Acid Orange 74, Acid Orange 142, Acid Orange 56, Acid Red 119, Acid Red 131, Acid Red 374, Acid Red 414, Acid Red 425, Acid Red 434, Acid Red 97, Acid Violet 48, Acid Yellow 42, Acid Yellow 49, Acid Yellow 79, Acid Yellow 99, Acid Yellow 194, Acid Yellow 232, Direct Black 168, Direct Blue 59, or mixtures thereof.

Particular preference is given to dyes which contain no transition metals.

The wet white tanned based on Carbamoylsulfonatgruppenhaltigen compounds yield white, yellowing resistant, leather and fur skins whose softness is adjusted by the products used in the retanning. The dyed leather and fur skins of the process according to the invention have extremely brilliant colorations, a very good through-coloring, a high levelness of the dyeing and also show a uniform coloring of the meat and scar sides. The dyed leather meets the authenticity requirements, for example, shoe upper leather, furniture leather and car leather, the dyed fur skins meet the authenticity requirements, for example, for applications in the medical field, for clothing and for decorative purposes. Preferred organic tanning agents of component b) are syntans, resin tanning agents, polymeric retanning agents and vegetable tanning agents.

The syntans are, for example, at least one condensation product based on

A) sulfonated aromatics, B) aldehydes and / or ketones and optionally

C) one or more compounds selected from the group of unsulfonated aromatics, urea and urea derivatives.

"Base of" means that the condensation product was optionally prepared from other reactants besides A, B and optionally C. Preferably, however, the condensation products in the context of this application are prepared only from A, B and optionally C.

For the purposes of this application, sulfonated aromatics are also understood to mean sulfomethylated aromatics. Preferred sulfonated aromatics are: naphthalenesulfonic acids, phenolsulfonic acid, sulfonated ditolyl ethers, 4,4'-dihydroxydiphenylsulfone, sulfonated diphenylmethane, sulfonated diphenyl, sulfonated terphenyl or benzenesulfonic acids, toluenesulfonic acids. Suitable aldehydes and / or ketones are in particular aliphatic, cycloaliphatic and aromatic in question. Preference is given to aliphatic aldehydes, particular preference being given to formaldehyde and other aliphatic aldehydes having 3 to 5 C atoms.

Suitable non-sulfonated aromatics are, for example, phenol, cresol or dihydroxydiphenylsulfone, dihydroxydiphenylmethane, ditolyl ether, dihydroxyditolyl ether, dihydroxyditolylsulfone, hydroxybenzoic acid.

As urea derivatives, for example dimethylolurea, melamine or guanidine can be mentioned.

Phenol and phenol derivatives such as, for example, phenolsulfonic acid, are often also linked by simultaneous action of formaldehyde and urea or by dimethylolurea (DE-A 1 113 457). Sulfonation of aromatic compounds are (according to Ullmann's Encyclopedia of Industrial Chemistry Volume 16 (4th edition) Weinheim 1979, p. 138) usually, without separating the unreacted starting compounds, alone or together with other starting compounds with formaldehyde condensed. A solubilizing group can also be introduced in phenols by sulfomethylating with the simultaneous action of alkali hydrogen sulfite and formaldehyde together with the condensation. This sulfomethylation is e.g. in DE-A 848 823.

Further preferred condensation products are condensates of ditolyl ether sulfonic acid with 4,4'-dihydroxydiphenylsulfone, and of phenolsulfonic acid with phenol, formaldehyde and urea. Particularly preferred condensation products are those which are obtained by condensation of sulfonated and optionally non-sulfonated aromatics with aliphatic aldehydes, preferably formaldehyde, sulfonated aromatics in particular meaning no sulfomethylated aromatics.

Such condensation products are preferably obtained by condensation of sulfonated naphthalene and sulfonated phenol or 4,4'-dihydroxydiphenylsulfone with formaldehyde or by condensation of naphthalenesulfonic acid and formaldehyde or by condensation of sulfonated ditolyl ether, sulfonated phenol with formaldehyde or by condensation of sulfonated phenol, urea, phenol Formaldehyde or by condensation of sulfonated phenol, urea, phenol, sulfonated ditolyl ether with formaldehyde. The condensation product preferably obtained in the condensation preferably has an average degree of condensation of 1 to 150, preferably from 1 to 20, in particular from 1 to 12. Preference is given here to products based on the condensation of naphthalenesulfonic acids, ditolyl ether sulfonic acids, phenolsulfonic acids, dihydroxydiphenylsulfone and phenol, and combinations of these raw materials with formaldehyde, glyoxal or glutaric dialdehyde and optionally urea or urea derivatives. Also suitable organic tanning agents are polycondensates based on dihydroxydiphenylsulfone / naphthalenesulfonic acid and formaldehyde, dihydroxydiphenylsulfone / ditolyl ether sulfonic acid and formaldehyde, dihydroxydiphenylsulfone / phenolsulfonic acid / ditolyl ether sulfonic acid / urea and formaldehyde (commercial tanning agents such as TANIGAN® BN, TANIGAN® PR, TANIGAN® 3LN, TANIGAN ® HO, TANIGAN® UW from Lanxess or mixtures thereof).

The organic tanning agents used, in particular the syntans, may contain other additives such as buffers or lignosulfonates.

Resin tanning agents are also suitable as organic tanning agents and are preferably polycondensates based on melamine, dicyandiamide, urea, lignin sulfonate or mixtures thereof with formaldehyde or glutardialdehyde.

The preferred polymeric retanning agents are high molecular weight water-soluble or water-dispersible products, e.g. B. from the (co) polymerization reaction of unsaturated acids and their derivatives with z. B. filling or greasing effect on leather. Preference is given to (co) polymerization of acrylic and methacrylic acid and their esters. Further polymeric retanning agents are the polyaspartic acid amides described in WO 97/06279, having a number average molecular weight of from 700 to 30,000, preferably from 1,300 to 16,000, obtainable by reacting

A. Polysuccinimide having a number average molecular weight of 500 to 10,000, preferably 500 to 6,000, in particular 1,000 to 4,000, with B. 5 to 90, preferably 20 to 80 mol%, based on Succinimideinheiten of polysuccinimide A, primary and / or secondary amine whose nitrogen substituents contain 1 to 60, preferably 1 to 36 carbon atoms, substituted by fluorine atoms, hydroxyl, amino groups and / or organosilicon radicals and / or interrupted by oxygen atoms, ester, amide, urea, urethane groups wherein at least 2.5, preferably at least 15, in particular at least 30 mol% of the

Nitrogen substituents of the amine contain at least 12 carbon atoms, optionally C. (i) Derivatives of C 1 -C 18 -monocarboxylic acids and / or C 2 -C 10 -dicarboxylic acids and / or (ii) monoisocyanates, diisocyanates or epichlorohydrin (for reacting amino and / or hydroxyl groups on the nitrogen substituents of the reaction product of A and B) ), and (mandatory) D. 95 to 10, preferably 80 to 20 mol% ring-opening base in the presence of water.

The preferred polyaspartic acid amides of WO 97/06279 are also to be considered incorporated herein.

Further polymeric retanning agents are, for example, (co) polymers which are a) structural units of the general formula I

steht, in der

stands in the

* indicates the orientation for the incorporation of the radical W into the formula I, and

Z represents the radicals -OH, -O ^" M ⁺ or -N-R'R ² , wherein R ¹ and R ² independently of one another represent hydrogen, optionally substituted alkyl radicals, alkenyl radicals, aralkyl radicals or cycloalkyl radicals which are denoted by O atoms, N atoms, Si atoms or amide, carbonate, urethane, urea, allophanate, biuret, isocyanurate groups or mixtures thereof may be interrupted and

M ^{+ is} H ⁺ or an alkali ion, an NH ₄ ion or a primary, secondary, tertiary or quaternary aliphatic ammonium radical which preferably carries a C 1 -C ₂₂ -alkyl or -hydroxyalkyl group, b) at least 10 mol% , based on the units of the formula I, structural units of the general formula Ia

enthält, wobei

contains, where

R ^{3 is} a hydrocarbon radical having C -C atoms, preferably a saturated C 1 -C 6 -alkyl radical, in particular C 9 -C 30 -alkyl radical, and

R ^ is hydrogen or has the same meaning as R ³ , and polyether units having an average molecular weight of 200-6000 g / mol.

Vegetable tannins are derived, for example, from vegetable sources tannins from the classes of condensed tannins or hydrolyzable tannins z. As chestnut extract, Mimosa, Tara or Quebracho. Vegetable tanning agents are also those which are made vegetable sources such as algae, fruits, such as rhubarb, olives, plant parts such as leaves, tree bark, roots, wood may optionally be obtained by a chemical or enzymatic modification and / or by extractive methods.

The organic tanning agents of component b) are usually in the form of aqueous solutions or aqueous dispersions in amounts of 3 to 100 wt .-%, preferably 10 to 50 wt .-% solids, based on the shaved weight of the leather or based on the wet weight the fur skins, in Nachgerbschritt and in amounts of 0 to 50 wt .-%, preferably 0 to 30% by weight of solid, based on the bladder weight of hides and skins (hairless) or based on the wet weight of hides and skins ( with hair), used in tanning. The anionic dyes can also be used simultaneously together with a fatliquoring agent and optionally hydrophobing agent.

Suitable hydrophobizing agents are, for example, polysiloxanes, preferably aqueous emulsions of polysiloxanes.

The hydrophobing is usually carried out by milling in a suitable apparatus in a conventional manner, i. at liquor lengths of 50 to 2000%, preferably 100 to 400%, based on the shaved weight of the leather or the wet weight of the fur skins, and at temperatures of 20 to 60 ° C, preferably 35 to 50 ° C, wherein at the beginning the pH values usually between 4.5 and 8.0, preferably between 4.8 and 5.5, lie. In general, the hydrophobing is completed in a time of 20 to 240, preferably 30 to 120 minutes. At the end of the hydrophobing, an optionally used emulsifier is usually fixed with acid, preferably formic acid, by adjusting a pH from 3.0 to 5.0, preferably from 3.8 to 4.0.

The effect of the hydrophobization can be enhanced by an aftertreatment with a ternary, trivalent or tetravalent metal salt, in particular with a basic chromium sulfate, with aluminum sulfate, aluminum formate, zirconium sulfate, titanium sulfate, calcium chloride or magnesium sulfate. Of the salts mentioned, expediently, based on the shaved weight of the leather or the wet weight of the fur skins, 0.5 to 5 wt .-%, preferably 1 to 2 wt .-%, is used. Of the indicated salts, basic aluminum chloride, aluminum triformate, titanium and zirconium sulfate are preferred. Many of the polysiloxanes described above as hydrophobizing agents require no metal salt fixation in order to achieve a good hydrophobicizing effect. The invention also relates to collagen fiber-containing substrates, in particular leather and fur skins, which have been tanned with at least one carbamoylsulfonate-containing compound and dyed with at least one anionic dye. In each case, the preferred forms described above also apply here.

Examples

 A) Production examples

Example AI: particulate polycarbamoylsulfonate with emulsifier and organic tanning agent To a solution of 95.5 g of sorbitan-polyethylene glycol (20) -monododecanoate (eg Eumulgin SML 20 (Cognis) or Tween 20 (Croda)), containing a total of 20 ethylene oxide units per Sorbitan unit is alkoxylated (HLB 16.7), in 3199.5 g of water and 4524.8 g of sodium bisulfite solution (NaHS0 ₃ , 38-40% in water) at 25 ° C and a pH of 4.36 under Stirring 1358.3 g of hexamethylene diisocyanate metered in from 40 minutes, wherein the temperature of the reaction mixture is adjusted to 50 ° C within. The pH is 5.62. Then 70.3 g of citric acid (anhydrous) dissolved in 70.3 g of water are added.

The mixture is stirred for 1 hour at 50 ° C, the reaction mixture is clear. Then it is cooled to 25 ° C within 2 hours. It is stirred for 1 hour at room temperature (20-23 ° C). The pH of the solution is 4.67. Then 211.3 g of citric acid (anhydrous) dissolved in 211.3 g of water are added and stirred for 15 minutes. The concentration is adjusted by adding 258.7 g of water. A clear 35.0% solution with a pH of 3.11 is obtained.

5000 g of a 35% solution of the above-described carbamoylsulfonate-containing compound and 5000 g of the 50% aqueous solution of a methylene-bridged aromatic polycondensate based on sulfonated ditolyl ether and 4,4'-dihydroxydiphenylsulfone are fed by means of a pump into a spray dryer with disc atomizer with the inlet temperature set to 165 ° C. The starting temperature was between 70 and 80 ° C. Caking in the dryer was not observed. An almost white finely divided powder with a bulk density of 562 g per 1000 ml was obtained, which had a dry residue of 99.27% (Mettler IR dryer HR 73P, 120 ° C., standard drying to constant weight). The obtained dust-free powder had a particle size of 5.0 μιη to 300 μιη. It dissolves very quickly in water without clumping. A solution of 5 g of powder in 50 ml of water had a pH of 3.40. Example A 2a: Particulate polycarbamoylsulfonate with HDI, without emulsifier

To a solution of 391.4 g of water and 527.6 g of sodium bisulfite solution (NaHSC> 3, 38-40% in water) are added 166.3 g of hexamethylene diisocyanate at 23 ° C in one portion, the mixture by means of a dispersing machine with rotor - Stator principle (Ultraturrax unit from IKA) is dispersed at 15,000 revolutions per minute. The temperature of the reaction mixture is raised to 60 ° C. within 60 minutes after addition of the isocyanate. The pH is 3.02 at the beginning and increases to 5.84 during the reaction. After a reaction time of 180 minutes, a turbid solution has formed. The speed is reduced to 12,000 revolutions per minute and cooled to 34 ° C within 2 hours. The batch is filtered. The clear solution has a pH of 4.34. There are added 28.3 g of citric acid monohydrate dissolved in 23.4 g of water. A solution having a solids content of 35.25% by weight and a pH of 2.12 is obtained. To this solution is added 3000 ml of acetone. It is stirred for 2 hours. The precipitated white solid is filtered off, washed with acetone and dried in vacuo at 20 ° C to constant weight (yield 90.3%>, residual moisture 0.5 wt .-%).

A solution of 1.75 g of powder in 5 ml of water is clear and has a pH of 2.20.

Example A 2b: Particulate polycarbamoylsulfonate with CHDI, without emulsifier

To a solution of 431.8 g of water and 554.1 g of sodium bisulfite solution (NaHSO ₃ , 38-40% in water), 191.8 g of bis (isocyanatomethyl) cyclohexane (mixture of isomers, or 1.4- and 1.3- Isomer) at 20 ° C. in one portion, the mixture being dispersed by means of a dispersing machine with a rotor-stator principle (Ultraturrax aggregate from IKA) at 15,000 revolutions per minute. After 2 hours, the setting of the dispersing unit is increased to 18,000 revolutions per minute. After another 30 minutes, the speed is increased to 20,000 revolutions per minute. The temperature of the reaction mixture is 3 hours after addition of the isocyanate 60 ° C. After a reaction time of 3.5 hours, the organic phase has disappeared. It is then cooled in 1.5 hours to 40 ° C, while further dispersed at 15000 revolutions per minute. After a total reaction time of 5 hours, the mixture is filtered and mixed with a solution of 28.3 g of citric acid monohydrate in 23.4 g of water, resulting in a pH of 2.58. A 35.0% solution with a pH of 2.58 is obtained.

At room temperature, 3000 ml of acetone are added to this solution. It is stirred for 2 hours. The precipitated white solid is filtered off, washed with acetone and dried in vacuo at 20 ° C to constant weight (yield 80.5%>, residual moisture 0.9 wt .-%>).

A solution of 1.75 g of powder in 5 ml of water is clear and has a pH of 2.60. Example A 2c: Particulate polycarbamoylsulfonate with HDI, without emulsifier

A solution of 326.5 g of water, 461.7 g of sodium bisulfite solution (NaHSC> 3, 38-40% in water) and 9.8 g of an adduct of 2 mol of citric acid and 1 mol of hexamethylene diisocyanate (obtained by drying the aqueous solution , Dispersion at 12000 rpm). To this template are added at 20 ° C 138.6 g of hexamethylene diisocyanate in one portion. The temperature of the reaction mixture is increased to 50 ° C. with dispersion within 60 minutes. After reaching 50 ° C., 7.8 g of citric acid monohydrate dissolved in 6.5 g of water are added, resulting in a pH of 3.05. The mixture is kept for 1 hour at 50 ° C and then cooled to 25 ° C within 2 hours. The pH of the clear solution is 2.92 at room temperature. There are 23.6 g of citric acid monohydrate dissolved in 19.5 g of water. After adjusting the solids content with 26.4 g of water to obtain a clear 35.0% solution with a pH of 2.30.

 At room temperature, 3000 ml of acetone are added to this solution. It is stirred for 2 hours. The precipitated white solid is filtered off, washed with acetone and dried in vacuo at 20 ° C to constant weight (yield 93.5%>, residual moisture 0.7 wt .-%).

A solution of 1.75 g of powder in 5 ml of water is clear and has a pH of 2.4.

B) Examples of use (wet white production)

The amounts of each of the products used (for example commercial products as supplied) are based on the weight of the raw materials or intermediates used.

B 1A: Preparation of wet white with tanning agent from example AI

Salted cowhides are washed commercially, limed, depilated, fleshed, and split. The pumice material (2.6 mm) is washed with 200% liquor and drained the liquor. For pre-delineation, the bins are prepared in 100% liquor and 0.2% sodium bisulphite, 0.1% of an ammonium-free decalcifying agent (eg Cismollan DLP, product of LANXESS) and 0.2% of a mixture of dicarboxylic acids (eg Cismollan DL, product of LANXESS) for 30 minutes at 30 ° C. The fleet is drained. Then 30% water, 0.2% sodium bisulfite and 0.1% of an ammonium-free decalcifying agent (eg Cismollan DLP, product of LANXESS) and 0.2% of a mixture of dicarboxylic acids (eg Cismollan DL, product of LANXESS) are added for further deliming and the barrel moves for 1 hour at 30 ° C. At pH 7.7, 1% of a beeignem (e.g., Levazyme AF, product of LANXESS) and 0.1% of a fatty alcohol ethoxylate-based degreaser (e.g., Cismollan AN 90) are added and agitated for an additional 45 minutes. The liquor is then drained and the buff washed twice.

(The following product quantities are based on the weight of the pelts) The prepared buff is conditioned for 30 minutes with 50% water, 0.2% sodium bicarbonate and 1% sodium acetate to pH 9.0 and treated with 1.7% of the product from Example AI (powder). After a penetration time of 20 minutes, a further 3.4% of the product from Example AI (powder) are added. During the following 1.5 hours at 40 ° C., the pH is adjusted to 8.1 by adding a total of 0.5% sodium carbonate (diluted 1:10 with water). Then the drum is moved for a further 2 hours at 40 ° C and the shrinkage temperature is measured (pH 7.65, Ts 68 ° C). The drum is moved for 2 hours in automatic mode (10 minutes / hour) and the pH is measured. Then 0.2% of a preservative (eg Preventol U-Tec G, product of LANXESS) is added and the pH reduced to 4.3 with 0.3% formic acid (85%, diluted 1:10). You move the barrel for 1.5 hours. Then the fleet is drained. The wet white leathers are washed and stored on the box. The shrink temperature is measured again (70 ° C). The leathers can wither without problems and fold to a thickness of 1.2 mm.

B 2A: Comparative Example: Preparation of Wet White with GTA Salted cowhides are commercially washed, limed, depilated, fleshed, and split. The pumice material (2.6 mm) is washed with 200%> liquor and drained the liquor. The bins are now delimed in the barrel in 100% liquor and 0.3% sodium bisulfite, 2.5% ammonium chloride, 0.2% formic acid 85% for 30 minutes. Then 0.5% of a Beizenzym (1000 trypsin units) is added and the barrel is agitated for 1 hour. The pH is 8.5. The liquor is drained and the breeze washed for 10 minutes and drained the fleet again.

(The following product quantities are based on the weight of the pelts)

The bins are now added with 30% water, 6% sodium chloride, 0.3% of a preservative (eg Preventol WB Plus L, product of LANXESS), 0.5% formic acid 85%, 0.90% sulfuric acid 96% for 70 minutes 30 ° C pickled. Then 1.00% of a fatliquor (e.g., Eureka 975 ES-I) is added and agitated for 3 hours. The liquor pH is 2.9. Subsequently, 3.00% of an aqueous glutaraldehyde solution (GTA, about 24%, pH 1.5 to 2.5) are added and pre-tanned for 2 hours. The drum is moved for another 2 hours in automatic mode (10 minutes / hour) and the pH is measured (pH 2.9).

For neutralization, 1.00% sodium formate is added and after 15 minutes runtime, another 1.00% sodium formate is added, resulting in a pH of 3.6. After a running time of 30 minutes, 1.00% of a neutralizing tanning agent based on aromatic sulfonic acids (eg TANIGAN PAK, product of LANXESS) is added. The barrel is agitated for 20 minutes, the pH is 3.75. Then 0.2% sodium bicarbonate is added and agitated for 30 minutes (pH 4.0). Now be 3.0 % of a 4,4'-dihydroxydiphenylsulfone based tanning agent (eg Tanigan HO, product of LANXESS) was added and the barrel agitated for 1 hour.

Thereafter, the liquor is drained, washed with 200% water and drained again. The Wet White is stored on the box. The shrink temperature is measured again (70 ° C). The leathers can wither without problems and fold to a thickness of 1, 2 mm.

B 3A: Preparation of wet white with tanning agent from Example A2a

Wet white was prepared analogously to Example B 1A using 2.1%, based on pum weight, of the tanning agent from Example A2a.

B 4A: Preparation of wet white with tanning agent from Example A2b Analogously to Example B 1A, wet white was produced using 2.1%, based on the weight of the body, of the tanning material from Example A2b.

B 5A: Preparation of wet white with tanning agent from Example A2c

Wet white was prepared analogously to Example B 1A using 2.1%, based on pum weight, of the tanning agent from Example A2c.

C) Dyeing Examples

 (The following use amounts of the products refer to the shaved weight of the leather) Example Cl: Preparation of a retanned leather with wet white from example B1A

Folded wet white (thickness 1.3 / 1.4 mm) from example B 1A is applied in a tannery with a liquor of 300% water (40 ° C.) and 0.2% of a fatty alcohol alkoxylate (eg CISMOLLAN AN 90, product of LANXESS ) (Diluted 1: 5) for 10 minutes. The fleet has a pH of 4.3 and is drained. Then 50% water (30 ° C), 3.0% of an organic tanning agent (eg TANIGAN RFS, product of LANXESS), 1.5% sodium formate and 3% of a Lickers (eg Baykanol Licker SL, product of LANXESS) (1 : 8 diluted) added. The barrel is moved for 30 minutes, the liquor has a pH of 4.8. Then 3.0% of a softening polymer tanning agent based on a modified polyamide carboxylic acid (eg LEVOTAN LB, product of LANXESS) (diluted 1: 3 with water) and after 10 minutes 5.0% of a polycondensate based on aromatic sulfonic acid and phenolic compounds (eg TANIGAN BN, product of LANXESS) and 8.0% of an adjuvant (eg Granofin TA, product of Clariant). After 30 minutes (pH 4.6) 5.0% of a polycondensate based on aromatic sulfonic acid and phenolic compounds (eg TANIGAN BN, product of LANXESS) and 8.0% vegetable tanning agent (Mimosa) were added and agitated for 150 minutes. The pH at this time is 4.4.

 Then 50% warm water (50 ° C) is added and the barrel is heated to 50 ° C. After 10 minutes, 3.0% of a fatliquor (e.g., BAYKANOL Licker SL, product of LANXESS) (diluted 1: 8) is added and agitated for 15 minutes. Thereafter, 3.0% of a polyacrylate-based filler polymer tanner (e.g., LEUKOTAN 1084, product of Dow Chemical) (diluted 1: 3) is added and agitated for another 45 minutes. Then it is acidified with 1.3% formic acid (diluted 1:10) in 2 portions to pH 3.8. After 45 minutes, the liquor is drained and washed.

 For dyeing, fresh liquor is used: 50% water (20 ° C) and 3.0% of a lickers (e.g., BAYKANOL Licker SL, product of LANXESS) (diluted 1: 8) are added and tumbled for 60 minutes. After a lead time of 2% of a naphthalenesulfonic acid condensate (eg TANIGAN PR, product of LANXESS), 3.0% of an anionic dye (BAYGENAL Black TDE, (CI Acid Black 210), product of LANXESS) is added and agitated for 60 minutes , Then add 100% water (60 ° C) and raise the temperature to 50 ° C. Then it is fixed with 3% formic acid (diluted 1:10). After 30 minutes, a pH of 3.2 is reached. As a pot staining, 1% of an anionic dye (BAYGENAL Black TDE (C.I. Acid Black 210), product of LANXESS) is added and the barrel is agitated for 20 minutes. Finally, fix with 1.0% formic acid for 30 minutes, drained the liquor and washed with 200% water. The leathers are unloaded and completed in the usual way by stretching, hanging drying and studs.

This gives a soft, full, no matter colored deep black leather with good color and high color brilliance. The fastness properties are excellent (light fastness grade 3, perspiration fastness grade 4-5). The migration fastness (PVC) has the rating of 5. Example C2: Preparation of a retanned leather with wet white from Example B 1A

Folded wet white (thickness 1.3 / 1.4 mm) from example B 1A is applied in a tannery with a liquor of 300% water (40 ° C.) and 0.2% of a fatty alcohol alkoxylate (eg CISMOLLAN AN 90, product of LANXESS ) (Diluted 1: 5) for 10 minutes. The fleet has a pH of 4.3 and is drained. Then 50% water (30 ° C), 3.0% of a neutralization tanning agent (eg TANIGAN PAK, product of LANXESS), 1.5% sodium formate and 3% of a Lickers (eg BAYKANOL Licker SIS, product of LANXESS) (1: 8 diluted) was added. The barrel is moved for 30 minutes, the fleet has a pH of 5.5. Then 3.0% of a softening polymer tanning agent based on a modified polyamide carboxylic acid (eg LEVOTAN LB, product of LANXESS) (diluted 1: 3 with water) and after 10 minutes 5.0% of a polycondensate based on aromatic sulfonic acid and phenolic compounds (eg TANIGAN BN, product of LANXESS) and 8.0% of an adjuvant (eg Granofin TA, product of Clariant). After 30 minutes (pH 4.8) 5.0% of a polycondensate based on aromatic sulfonic acid and phenolic compounds (eg TANIGAN BN, product of LANXESS) and 8.0% of a vegetable extracts containing 4,4'-Dihydroxydiphenylsulfon-based Syntans (eg TANIGAN F, product of LANXESS) and 4.0% of a formaldehyde-free resin tanning agent (eg RETINGAN ZF, product of LANXESS) was added and agitated for 150 minutes. The pH at this time is 4.9.

 Then 50% warm water (50 ° C) is added and the barrel is heated to 50 ° C. After 10 minutes, a mixture of fatliquors consisting of 8.0% Atlasol 170 (product of Atlas), 3.0% BAYKANOL Licker TSI (product of LANXESS), 3.0% Atlasol WRM (product of Atlas) is added and Moved for 15 minutes. Thereafter, 3.0% of a polyacrylate-based filler polymer tanning material (e.g., LEUKOTAN 970, product of Dow Chemical) (diluted 1: 3) is added and agitated for a further 60 minutes. It is then acidified to pH 3.8 with 2.0% formic acid (diluted 1:10). After 30 minutes, the liquor is drained and washed.

For dyeing, fresh liquor is used: 50% water (20 ° C) and 3.0% of a lickers (e.g., BAYKANOL Licker SL, product of LANXESS) (diluted 1: 8) are added and tumbled for 60 minutes. After a lead time of 15 minutes with 2% of a naphthalenesulfonic acid condensate (eg TANIGAN PR, product of LANXESS), 3.0% of an anionic dye (BAYGENAL Yellow 4GL, (CL Acid Yellow 79), product of LANXESS) is added and 60 minutes emotional. Then add 100% water (60 ° C) and raise the temperature to 50 ° C. Then it is fixed with 3% formic acid (diluted 1:10). After 30 minutes, a pH of 3.2 is reached. As a pot staining, 1% of an anionic dye (BAYGENAL Yellow 4GL (C.L Acid Yellow 79), product of LANXESS) is added and the barrel is agitated for 20 minutes. Finally, fix with 1.0% formic acid for 30 minutes, drained the liquor and washed with 200% water. The leathers are unloaded and completed in the usual way by stretching, hanging drying and studs.

This gives a soft, full, no matter colored bright yellow leather with good color and high color brilliance. The fastness properties are excellent (light fastness grade 6, perspiration fastness grade 5). The migration fastness (PVC) has the rating of 5. Example C3: Preparation of a retanned leather with wet white from example B3A

Example C2 was repeated except that the wet white from Example B3A was used and used as the anionic dye BAYGENAL Red GX (Acid Red 374). This gives a soft, full, no matter colored red leather with good color and high color brilliance. Example C4: Preparation of a retanned leather with wet white from example B4A

Example C2 was repeated except that the wet white from Example B4A was used and used as the anionic dye BAYGENAL Brown CGG New (Acid Brown 83). This gives a soft, full, no matter colored brown leather with good color and high color brilliance.

Example C5: Preparation of a retanned leather with wet white from example B5A

 Example C2 was repeated except that the wet white from example B5A was used and used as the anionic dye BAYGENAL Brown CGG New (Acid Brown 83). This gives a soft, full, no matter colored brown leather with good color and high color brilliance.

Example C6: Comparative Example / Preparation of a retanned leather with wet white from example B2A (GTA)

 Example C2 was repeated except that the GTA-based wet white from Example B2A was used and used as the anionic dye BAYGENAL Yellow 4GL (C.I. Acid Yellow 79). This gives a soft, less full, dull yellow leather with insufficient coloring. The leather undergoes a color shift to a dirty yellow during storage. The leather thus has significant disadvantages over the inventive example C2.

Claims

claims A process for dyeing collagen fiber-containing substrates treated with at least one carbamoylsulfonate-containing compound, which comprises subsequently dyeing the thus treated collagen fiber-containing substrate with at least one anionic dye, wherein the carbamoylsulfonate-containing compound is a reaction product of at least one organic polyisocyanate and at least one bisulfite and / or disulfite, characterized in that the organic polyisocyanate has a molecular weight of less than 400 g / mol and NCO groups bound to aliphatics or cycloaliphatic. Dyeing process according to Claim 1, characterized in that at least one of the anionic dyes is Acid Black 2, Acid Black 52, Acid Black 71, Acid Black 84, Acid Black 107, Acid Black 173, Acid Black 194, Acid Black 210, Acid Black 220, Acid Blue 234, Acid Blue 25, Acid Blue 90, Acid Blue 1 13, Acid Blue 158, Acid Blue 193, Acid Blue 284, Acid Blue 349, Acid Brown 75, Acid Brown 83, Acid Brown 161, Acid Brown 194, Acid Brown 282, Acid Brown 298, Acid Brown 311, Acid Brown 314, Acid Brown 322, Acid Brown 324, Acid Brown 349, Acid Brown 355, Acid Brown 365, Acid Brown 413, Acid Brown 414, Acid Brown 425 Acid Brown 431, Acid Brown 432, Acid Brown 434, Acid Brown 452, Acid Brown 75, Acid Brown 97, Acid Brown Mix, Acid Green 26, Acid Green 68, Acid Green 104, Acid Green 111, Acid Orange 33, Acid Orange 61, Acid Orange 74, Acid Orange 142, Acid Orange 56, Acid Red 119, Acid Red 131, Acid Red 374, Acid Red 414, Acid Red 425, Acid Red 434, Acid Red 97, Acid Violet 48, Acid Yellow 42, Acid Yellow 49, Acid Yellow 79, Acid Yellow 99, Acid Yellow 194, Acid Yellow 232, Direct Black 168 and / or Direct Blue 59. 3. Dyeing process according to claim 1, characterized in that as anionic dye at least Acid Black 2, Acid Black 52, Acid Black 71, Acid Black 84, Acid Black 107, Acid Black 173, Acid Black 194, Acid Black 210, Acid Black 220, Acid Blue 234, Acid Blue 25, Acid Blue 90, Acid Blue 1 13, Acid Blue 158, Acid Blue 193, Acid Blue 284, Acid Blue 349, Acid Brown 75, Acid Brown 83, Acid Brown 161, Acid Brown 194 Acid Brown 282, Acid Brown 318, Acid Brown 311, Acid Brown 312, Acid Brown 322, Acid Brown 324, Acid Brown 349, Acid Brown 355, Acid Brown 365, Acid Brown 413, Acid Brown 414, Acid Brown 425, Acid Brown 431, Acid Brown 432, Acid Brown 434, Acid Brown 452, Acid Brown 75, Acid Brown 97, Acid Brown Mix, Acid Green 26, Acid Green 68, Acid Green 104, Acid Green 111, Acid Orange 33, Acid Orange 61, Acid Orange 74, Acid Orange 142, Acid Orange 56, Acid Red 1 19, Acid Red 131, Acid Red 374, Acid Red 414, Acid Red 425, Acid Red 434, Acid Red 97, Acid Violet 48, Acid Yellow 42, Acid Yellow 49, Acid Yellow 79, Acid Yellow 99, Acid Yellow 194, Acid Yellow 232, Direct Black 168, Direct Blue 59 or mixtures thereof. A method of dyeing according to claim 1, characterized in that the carbamoylsulfonate-containing compound is a reaction product of organic polyisocyanates and bisulfite and / or disulfite, wherein the organic polyisocyanate is a polyisocyanate having an NCO functionality of 1, 8 to 2.5. Dyeing process according to claim 1, characterized in that the organic polyisocyanate is a 1, 4-diisocyanatobutane, 1,6-diisocyanatohexane (HDI), 1, 5-diisocyanato-2,2-dimethylpentane, 2,2,4- or 2,4,4-trimethyl-1, 6-diisocyanatohexane (TMHI), 1, 3- and 1, 4-diisocyanatohexane, 1, 3- and 1, 4-diisocyanato-cyclohexane (CHDI) and any desired mixtures of these isomers, 1-isocyanato-2-isocyanatomethyl-cyclopentane, 1 , 2-, 1, 3- and 1, 4-bis (isocyanatomethyl) cyclohexane and any mixtures of isomers, 1, 2-, 1, 3- and 1, 4-bis (isocyanatoethyl) cyclohexane and any mixtures of these isomers , 1, 2-, 1, 3- and 1, 4-bis (isocyanato-n-propyl) -cyclohexane and any mixtures of these isomers, 1 - isocyanatopropyl-4-isocyanatomethyl-cyclohexane and isomers, l-isocyanato-3,3 , 5-trimethyl-5-isocyanatomethylcyclohexane (IPDI), 1-isocyanato-1-methyl-4-isocyanatomethylcyclohexane (IMCI), 2,4'- and 4,4'-diisocyanatodicyclohexylmethane (Hi ₂ MDI) and isomers, dimeryl diisocyanate (DDI), bis (isocyanatomethyl) bicyclo [2.2.1] heptane (NBDI), bis (isocyanatomethyl) tricyclo [5.2.1.0 ² ' ⁶ ] decane (TCDDI) and isomers and any mixtures thereof Diisocyanates and xylylene diisocyanates of the formulas Process according to Claim 1, characterized in that the compound containing carbamoylsulfonate groups is used in combination with at least one nonionic, ester group-containing compound. containing alkoxylated polyol having an HLB value of at least 13 (cl) and / or an alkyl glycoside (c2) and / or a nonionic ester group-free alkoxylated alcohol (c3) is used. 7. The method according to claim 1, characterized in that the Carbamoylsulfonatgruppen- containing compound is used in the absence of emulsifiers. 8. The method according to claim 1, characterized in that as collagen fiber-containing substrates leather or fur skins are used. 9. Use of anionic dyes for dyeing collagen fiber-containing substrates, in particular leathers and furskins, which have been treated in the presence of carbamoylsulfonate-containing compounds and optionally organic tanning agents but in the absence of mineral or other organic reactive tanning agents.  10. Collagen fiber-containing substrates, in particular leather or fur skins, which have been tanned with at least one carbamoylsulfonate-containing compound and dyed with at least one anionic dye.