Basf Aktiengesellschaft

Dietrich Lach

Rolf Streicher

Erwin Hahn

Ortwin Schaffer

Guenter Hansen

Rolf Fikentscher

Heinz Eilingsfeld

Udo Bergmann

Georg Zeidler

Kurt Schneider

Rainer Strickler

Klaus Ebel

Alfred Oftring

Wolfgang Reuther

Werner Ostertag

Klaus Grychtol

Manfred Herrmann

Guenter Eckert

Horst Belde

Henning Wienand

Karl Fischer

Franz Feichtmayr

Michael Thomas

Gerhard Bolz

Franz Leppmeier

Hilmar Bruenemann

Lothar Wuertele

Lothar Hohr

Bernhard Magerkurth

Werner Maltry

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 of

Pigment preparations

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.

Condensates of bis-(4-hydroxyphenyl) sulfone as tanning assistants,

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

Finishing of leather

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.

Tanning assistant

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.

Deliming of hides and use of cyclic esters of sulfurous acid as deliming

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.3 H, Z is alkyl of 1 to 4 carbon atoms or alkoxy of 1 to 4 carbon atoms, m is from 1 to 10, n is from 0 to 5, p is from 0 to 2, q is from 0 to 2, and o is 4-(p+q) if A is benzene, and is 6-(p+q) if A is naphthyl, and their alkali metal and ammonium salts for retanning, and a process for retanning and dyeing mineral tanned leathers

Amphoteric condensates and their use in retanning

The invention relates to basic chromium aluminum sulfates which are soluble in cold water and are of the general formula

Basic chromium aluminum sulfates and their preparation

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.

Carboxyl- and amino-containing copolymer for after-tanning mineral

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 formula

Metal complexes of dis- or trisazo compounds containing a middle

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.2 is methyl, ethyl or allyl; the rings B and E may additionally be substituted by methyl, ethyl, methoxy, ethoxy, chlorine, bromine or hydroxysulfonyl, with the proviso that D.sup.2 has a hydroxyl group ortho to the azo bond; or the iron, manganese, cobalt, chromium, nickel or copper complexes of this dye. These compounds, particularly in the form of their metal complexes are suitable for dyeing nitrogen-containing fibers such as wool, and preferably, leather. The present dyes yield very fast brown hues, in particular on retanned leather.

Dis-, tris-, and tetrakisazo compounds containing resorcinol,

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.

Complex dye mixture containing at least two cobalt 1:2 complexes of azo

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.

Preparation of water-soluble or self-dispersing resin tanning agents

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.

Tanning agent, its preparation and its use for retanning

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.

Deliming hides

An auxiliary for the soaking of hides and skins, which consists of a salt of the formula I

Growing community of inventors

Friedelsheim, Germany

Dietrich Lach