Abstract: Process for the production of leather, wherein, after liming, deliming and, if appropriate, pickling, animal hides are pretanned or tanned with a mixture of compounds comprising (a) at least one organic tanning agent and (b) a mixture of (b1) at least one C3-C12-dicarboxylic acid (b2) and at least one further acidic compound selected from C1-C3-mono- or C3-C12-dicarboxylic acids, or salts thereof.

Abstract: Horny substances are removed from hides, pelts or skins of dead animals by treating the hides, pelts or skins in aqueous liquor with one or more compounds of the formula I or their corresponding alkali metal or alkaline earth metal salts or ammonium or phosphonium salts, the variables being defined as follows: R1 is selected from hydrogen and C1-C12-alkyl, unsubstituted or substituted by one or more S—H or O—H groups; X1 to X4 are identical or different and are selected from hydrogen, C1-C4-alkyl, O—H, S—H and N—HR2, R2 is hydrogen or C1-C12-alkyl or a C1-C4-Alkyl-C?O group, at least one radical X1 to X4 being S—H when R1 contains at least one sulfur atom and at least two radicals X1 to X4 being S—H when R1 contains no sulfur atom.

Abstract: The invention relates to a method for removing horn substances from animal skin. The method is characterized in that animal skins are treated in an aqueous bath containing between 0.05 and 5 wt. %, in relation to the weight of the salt, of at least one compound of general formula I or the corresponding alkali metallic salts or alkaline-earth metallic salts thereof or ammonium or phosphonium salts.

Abstract: Horny substances are removed from animal hides by a process wherein animal hides are treated in a liquor comprising from 0.05 to 5% by weight, based on the salted weight, of one or more compounds of the formula I or the corresponding alkali metal or alkaline earth metal or ammonium or phosphonium salts thereof, the variables being defined as follows: R1 is selected from hydrogen and C1-C12-alkyl, unsubstituted or substituted by one or more S—H or O—H groups; X1 to X4 are identical or different and are selected from hydrogen, C1-C4-alkyl, O—H, S—H and N—HR2, R2 is hydrogen or C1-C12-alkyl or a C1-C4-alkyl-C?O group, at least one of the radicals X1 to X4 being S—H, and, if R1 contains neither O—H nor S—H, at least one further radical from among X1 to X4 is selected from S—H, OH and NH—R2, and furthermore with at least one compound which catalyzes the hydrolysis of peptide bonds.

Abstract: Leather is produced by a process comprising at least two of the following process steps A) to D): A) use of one or more polyelectrolytes in the production of semifinished products or intermediate products, comprising the addition of one or more polyelectrolytes in at least one of the steps (a) to (d) (a) together with from 0 to 1.5% by weight, based on the salted weight, of lime, immediately before or during liming, (b) before or during deliming, (c) before or during bating, (d) together with, altogether, from 0 to 3% by weight, based on the pelt weight, of alkali metal or alkaline earth metal salt, immediately before or during pickling; B) treatment of the hides during liming in an aqueous liquor with one or more compounds of the formula B.1 ?or the corresponding alkali metal, alkaline earth metal, ammonium or phosphonium salts thereof, R10 and X1 to X4 having the meanings stated in the description, with the proviso that at least two mercapto groups are present in the compound or the compounds B.

Abstract: The present invention relates to C4–C6-polymercaptopolyols as regulators in the free-radically initiated solution and precipitation polymerization of ethylenically unsaturated monomers.

Abstract: The invention relates to a degreaser for treating hides, skins, pelts and other intermediates in leather and fur manufacture and also wool or related proteinaceous materials that is based on nonionic surfactants of the type of alcohol alkoxylates, comprising alcohol alkoxylates obtained by reaction of at least one alcohol ROH with n mol of at least one alkylene oxide per mole of alcohol ROH, where R is an alkyl radical of 5 to 30 carbon atoms which has a main chain, of 4 to 29 carbon atoms that has at least one C1— to C10-alkyl branch attached in the chain middle; the alkylene oxide has 2 to 6 carbon atoms, and n is an integer from 1 to 100. The invention further relates to a process for degreasing hide, skins, pelts and other intermediates of leather and fur manufacture and wool or related proteinaceous materials, which comprises using a degreaser according to the present invention, and to the use of the degreasers.

Abstract: The invention relates to a method for removing horn substances from animal skin. Said method is characterised in that animal skins are treated in an aqueous bath containing between 0.05 and 5 wt. %—in relation to the weight of the salt—of at least one compound of general formula I or the corresponding alkali metallic salts or alkaline-earth metallic salts thereof or ammonium or phosphonium salts, the variables having the following definitions: R1 is selected from hydrogen or C1-C12 alkyl, unsubstituted or substituted by at least one S—H group or one O—H group; X1 to X4 are the same or different and selected from hydrogen, C1-C4 alkyl, O—H, S—H or N—HR2; and R2 represents hydrogen or C1-C12 alkyl or a C1-C4-alkyl-C?O group, at least one X1 to X4 representing S—H. If R1 contains neither O—H nor S—H, at least one other X1 to X4 is selected from S—H, OH or NH—R2. Said aqueous bath also comprises at least one compound which catalyses the hydrolysis of peptide compounds.

Abstract: Horny substances are removed from hides, pelts or skins of dead animals by treating the hides, pelts or skins in aqueous liquor with one or more compounds of the formula I or their corresponding alkali metal or alkaline earth metal salts or ammonium or phosphonium salts, the variables being defined as follows: R1 is selected from hydrogen and C1-C12-alkyl, unsubstituted or substituted by one or more S—H or O—H groups; X1 to X4 are identical or different and are selected from hydrogen, C1-C4-alkyl, O—H, S—H and N—HR2, R2 is hydrogen or C1-C12-alkyl or a C1-C4-Alkyl-C?O group, at least one radical X1 to X4 being S—H when R1 contains at least one sulfur atom and at least two radicals X1 to X4 being S—H when R1 contains no sulfur atom.

Abstract: A process for the production of semifinished products and intermediates in the production of leather using one or more organic polyelectrolytes comprises at least one of the following steps: (a) Addition of one or more polyelectrolytes and from 0 to 0.7% by weight, based on the salted weight, of lime immediately before or during liming, (b) addition of one or more polyelectrolytes before or during deliming, (c) addition of one or more polyelectrolytes before or during bating, (d) addition of one or more polyelectrolytes and a total of from 0 to 3% by weight, based on the pelt weight, of alkali metal or alkaline earth metal salt immediately before or in the pickle.

Abstract: The present invention relates to C4-C6-polymercaptopolyols as regulators in the free-radically initiated solution and precipitation polymerization of ethylenically unsaturated monomers.