Abstract: Pigment preparations useful for pigmenting or delustering finishes for leather and leather substitutes consist essentially of pigments or delusterants or a mixture thereof, binders, water and if desired further customary dispersants and auxiliaries, the binders used being copolymers ofA) from 40 to 80% by weight of at least one aromatic vinyl compound of the general formula I ##STR1## where R.sup.1, R.sup.2 and R.sup.3 are each hydrogen, methyl or ethyl and n is 1 or 2,B) from 20 to 60% by weight of acrylic acid or methacrylic acid or a mixture thereof, andC) from 0 to 10% by weight of further copolymerizable monomers,in the form of their salts.

Abstract: A condensate of bis-(4-hydroxyphenyl) sulfone, an aldehyde, a dialdehyde and/or glyoxylic acid and aminoacetic acid or an N-substituted aminoacetic acid is prepared and used as a tanning assistant, in a process for tanning leather in combination with, in particular, aluminum tanning agents.

Abstract: Leather is finished on the basis of a purely aqueous system using aqueous polymer dispersions, casein and crosslinking agents in the bottoming and seasoning.

Abstract: A tanning assistant useful in particular for tanning in combination with aluminum tanning agents is obtained by condensing melamine with glyoxal and/or glyoxylic acid and optionally with an aromatic compound which has a phenolic hydroxyl group or optionally with a condensable nitrogen compound.

Abstract: In a particularly time-saving and economical process for deliming hides, a cyclic ester of sulfurous acid with an aliphatic 1,2-diol is used as the deliming agent.

Abstract: Amphoteric condensates of the general formula I ##STR1## where A is a benzene or naphthyl radical, B is a radical derived from the group consisting of urea, biuret, dicyanodiamide or melamine, or a mixture of these radicals, X is --CH.sub.2 --COOH, CH.sub.3 --CH--COOH, CH.sub.3 --CH.sub.2 --CH--COOH, (CH.sub.3).sub.2 C--COOH or --CH.sub.2 --CH.sub.2 --COOH, R is H, alkyl of 1 to 4 carbon atoms or one of the radicals, X, Y is --CH.sub.2 SO.sub.3 H or --SO.sub.

Abstract: The invention relates to basic chromium aluminum sulfates which are soluble in cold water and are of the general formulaCr.sub.x Al.sub.2-x (OH).sub.2 y. (SO.sub.4).sub.3-y.n H.sub.2 Owhere x is from 0.1 to 1.9, y is from 0.01 to 2 and n is from 4 to 24, and a process for the preparation thereof. The process comprises reacting chromium (III)--containing waste sulfuric acid having a water content of 20-50% by weight with aluminum oxide and/or aluminum oxide hydroxide and/or aluminum hydroxide at a temperature of 100.degree. to 200.degree. C. The molten product is converted to droplet form and allowed to solidify in free fall.

Abstract: An amino-containing and carboxyl-containing polymer tanning agent containing more carboxyl groups than amino groups, when used for retanning mineral-tanned leather, gives, alone or in combination with conventional anionic retanning agents, leather which is readily dyeable and has good sensory properties.

Abstract: Compounds containing sulfonic acid groups and of the general formula I ##STR1## where D.sup.1 is a radical of a diazo component, X.sup.1 and X.sup.2 independently of one another are each hydroxyl or unsubstituted or substituted amino, Y is hydrogen, chlorine, methyl, hydroxysulfonyl or a radical of the formulaD.sup.3 --N.dbd.N--and D.sup.2 is a radical of the formula ##STR2## D.sup.3 is a radical of a diazo component from the aniline or aminonaphthalene series, K is a radical of a coupling component from the benzene or naphthalene series, and the rings in the coupling component D.sup.2 may furthermore be substituted by chlorine, methyl, methoxy, hydroxysulfonyl, aminosulfonyl, hydroxyl or acylamino, and metal complexes of such compounds, give very fast, brown dyeings, particularly on leather.

Abstract: The present invention discloses substituted phenyl di and trisazo dyes free of reactive groups having two or three sulfonic acid groups, of the general formula: ##STR1## wherein D.sup.1 is ##STR2## Z is hydrogen or D.sup.4 --N.dbd.N--; D.sup.2 is phenyl substituted by hydroxyl, hydroxysulfonyl, chlorine or nitro, or is naphthyl substituted by hydroxy, hydroxysulfonyl or nitro, X, independently of one another, are hydroxyl or amino, D.sup.3 is phenyl which is substituted by hydroxysulfonyl, chlorine, bromine, methyl, methoxy, ethoxy, nitro, phenylamino, sulfophenylamino or nitrosulfophenylamino, or is naphthyl which is substituted by hydroxysulfonyl; D.sup.4 is phenyl which is unsubstituted or substituted by methyl, ethyl, methoxy, ethoxy, chlorine, bromine, nitro, sulfamoyl or hydroxysulfonyl, or is naphthyl which is substituted by hydroxysulfonyl; and R.sup.

Abstract: Mixtures of two or more cobalt 1:2 complexes of azo dyes of the formula I ##STR1## where R is ##STR2## where R.sup.1 is hydrogen, C.sub.1 -C.sub.18 -alkyl, or hydroxyalkyl or alkoxyalkyl which may be interrupted by oxygen, and X and Y are hydrogen, fluorine, chlorine, bromine, C.sub.1 -C.sub.4 -alkyl or C.sub.1 -C.sub.4 -alkoxy.The mixtures according to the invention are particularly useful for dyeing leather.

Abstract: Water-soluble or self-dispersing resin tanning agents are prepared by heating from 5 to 30% by weight of melamine, from 15 to 45% by weight of urea, from 20 to 35% by weight (calculated as anhydrous material) of formaldehyde and from 15 to 55% by weight of sodium bisulfite or of a corresponding amount of some other salt of sulfurous acid for from two to twelve hours in aqueous solution at 40.degree.-120.degree. C. and a pH of from 5 to 9.

Abstract: Mineral tanned leather is frequently retanned with synthetic tanning agents to improve the fullness and softness, but leather retanned by the prior art methods is difficult to dye in full shades with anionic dyes. According to the invention, condensation products of C.sub.1-4 aldehydes with certain aromatic sulfonic acids or carboxylic acids containing amino groups are employed for retanning, thereby improving the receptivity of the leather for anionic dyes. These acids have the general formula ##STR1## where X and X' are independently H, --CH.sub.2 --SO.sub.3 H or --CH.sub.2 --OH, A is a benzene radical, Y and Z are independently H, --SO.sub.3 H or --CO.sub.2 H, R is H or C.sub.1-4 -alkyl and n is from 0 to 10, with the proviso that at least one sulfonic acid or carboxyl group is present in the molecule.

Abstract: Conventionally limed hides are delimed for from one to six hours under conventional deliming conditions in respect of liquor length, temperature and pH of the liquor, by a process in which a cyclic carbonate of a polyhydric aliphatic alcohol of 2 to 6 carbon atoms is employed as the active agent.

Abstract: An auxiliary for the soaking of hides and skins, which consists of a salt of the formula IM.sup.+ [O.sub.3 S--S--R].sup.- Iwhere R is an organic radical of 1 to 8 carbon atoms, which may carry one or more functional groups, and M.sup.+ is one equivalent of a cation, mixtures thereof with other conventional soaking auxiliaries, and processes for their use. Using the novel auxiliary avoids all toxicity hazards and odor nuisance, as well as avoiding oxidation losses, and achieves good loosening of the hair.

Abstract: A process for dyeing grain leather with anionic dyes under the conventional conditions for exhaustion methods, in the presence of two specific surfactants. The combined use of the two surfactants results, in the case of cationically tanned (essentially mineral-tanned) leather, in an improvement in the levelness and dye penetration and in the case of anionically tanned (synthetics-tanned or vegetable-tanned) or retanned leather, in an increase in depth of the color.The two surfactants are(a) an aliphatic alcohol of 9 to 24 carbon atoms oxyethylated with from 3 to 120 ethylene oxide units and(b) an aliphatic amine of 8 to 20 carbon atoms oxyethylated with from 6 to 80 ethylene oxide units,and they are used in a weight ratio of a:b of from 1:4 to 4:1 and in a total amount of from 0.3 to 3%, based on shaved weight.

Abstract: A process for deliming hides, in which, instead of using conventional acids or acid salts, esters which hydrolyze under the conventional deliming conditions are employed. This avoids the disadvantages associated with an overdose of conventional deliming agents.

Abstract: A process for separating 1,5-dinitroanthraquinone and 1,8-dinitroanthraquinone by heating a dinitroanthraquinone mixture, in a mixture of from 5 to 85 per cent by weight of N-methylpyrrolidone and from 95 to 15 per cent by weight of an organic liquid which boils at from 80.degree. to 210.degree. C and is miscible in all proportions with N-methylpyrrolidone, at from 60.degree. to 180.degree. C, and separating off the undissolved material, at the extraction temperature, after the solution equilibrium has been reached. The insoluble material contains more than 85 per cent by weight, and as a rule more than 90 per cent by weight, of 1,5-dinitroanthraquinone. From the extract, it is possible to isolate the dissolved 1,8-dinitroanthraquinone together with the dissolved 1,5-dinitroanthraquinone and any byproducts which may be present.

Abstract: A process for the isolation of mixtures of 1,5-dinitroanthraquinone and 1,8-dinitroanthraquinone which have a high content of .alpha.,.alpha.'-dinitroanthraquinones by heating a suspension of the crude dinitroanthraquinone mixture in certain organic liquids at from 60.degree. to 200.degree. C until solution equilibrium has been set up, and separating the undissolved material from the solution. The undissolved material contains more than 90% and as a rule more than 95% by weight of 1,5-dinitroanthraquinone and 1,8-dinitroanthraquinone. The pure mixture of 1,5-dinitroanthraquinone and 1,8-dinitroanthraquinone may be used for the manufacture of dyes.