Abstract: The present invention relates to a process for dyeing leather with at least one dye F which has at least one alkaline-activable group of the formula A; where - - - - denotes the bond to the rest of the dye molecule; X is an electron-attracting radical, k is 1, 2 or 3, n is 0 or 1 and B is a CH?CH2 group or a CH2—CH2-Q group, where Q is an alkaline-detachable group, which comprises treating the leather with an aqueous float comprising at least one dye F at a pH of not less than 7.5. The present invention also relates to novel dyes which are particularly useful for reactive dyeing of leather.

Abstract: The present invention relates to a process for dyeing leather with at least one dye F which has at least one alkaline-activable group of the formula A; where - - - - denotes the bond to the rest of the dye molecule; X is an electron-attracting radical, k is 1, 2 or 3, n is 0 or 1 and B is a CH?CH2 group or a CH2—CH2-Q group, where Q is an alkaline-detachable group, which comprises treating the leather with an aqueous float comprising at least one dye F at a pH of not less than 7.5. The present invention also relates to novel dyes which are particularly useful for reactive dyeing of leather.

Abstract: Mixtures comprise the dye of the formula I ##STR1## the dye C.I. Sulphur Black 1 (53 185), at least one disazo dye of the formula II ##STR2## where the ring A, X.sup.1, R.sup.1, R.sup.2 and R.sup.

Abstract: Dyed leather is aftertreated with quaternized condensation products ofA) a precondensate of one or more trialkanolamines of the Formula I ##STR1## B) a) a carboxylic acid derivative thereof IIa ##STR2## b) a carboxamide IIb ##STR3## c) an epichlorohydrin IIc ##STR4## d) a monofunctional compound IId R.sup.9 --Y IIde) a bifunctional compound IIeZ'--R.sup.10 --Z.sup.

Abstract: Leather is dyed with pigments in an aqueous liquor at from 20.degree. to 60.degree. C. in the presence of an alkoxylated amine of 20 or more carbon atoms.

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: 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: 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: 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: 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.