Abstract: A deliming composition and a deliming method using graft polymers from polysaccharides and/or polypeptides or the corresponding derivatives, obtainable by radical polymerization of a monomer, selected at least from, or a monomer mixture of, acrylic acid or methacrylic acid or the mixtures thereof.

Abstract: The invention relates to specific chrome tanning agents and also to their use for the tanning of hides and skins, and to the leather and pelts obtainable as a result. It further provides a new process wherein the protein-masked chrome tanning agents of the invention are obtained from materials containing chromium and collagen, more particularly from leather production wastes such as leather shavings, for example. This enables recycling of chromium-containing leather production wastes, thereby permitting a significant reduction in the amount of such wastes, a fact which leads to considerable economic, environmental and logistical advantages.

Abstract: A method of preparing hydrophobicizing leather treatment compositions includes the steps of a) free-radically initiated copolymerization of i) at least one ethylenically unsaturated carboxylic acid or its derivatives, and ii) at least one (meth)acrylate of a primary saturated C8 to C22 alcohol, b) mixing the reaction mixture obtained after step a) with water, c) salting at least some of the carboxyl groups of the reaction mixture obtained after step b) with a base, and d) shearing the reaction mixture obtained after step c) to an average particle size of 0.05-10 ?m, wherein step a) is carried out in oil as reaction medium and wherein the atmosphere in step a) contains less than 0.1% by volume of an oxidizing gas.

Abstract: The invention relates to a device for reducing the odor of tanned leather, comprising a treatment chamber, which is designed to dry tanned leather and/or treat dried leather, and at least one odor reducing reservoir, wherein the at least one odor reducing reservoir has at least one odor-neutralizing substance, and a gas-exchange connection is provided between the treatment chamber and the odor reducing reservoir.

Abstract: A composition including an acetal of an aldehydic tanning agent for tanning hides and/or pelts, as well as a method for tanning hides and/or pelts in order to produce leather, wherein an acetal of an aldehydic tanning agent is used. By reducing the pH, the aldehydic tanning agent can be released, whereby a tanning step is initiated. The composition according to the invention and the method according to the invention are characterized by lower toxicity compared to conventional compositions and tanning methods based on aldehydic tanning agents. Furthermore, improved penetration of the tanning agents into deeper layers of the hide and/or the pelt is possible, so that particularly homogeneous tanning is achieved.

Abstract: A composition including an acetal of an aldehydic tanning agent for tanning hides and/or pelts, as well as a method for tanning hides and/or pelts in order to produce leather, wherein an acetal of an aldehydic tanning agent is used. By reducing the pH, the aldehydic tanning agent can be released, whereby a tanning step is initiated. The composition and the method are characterized by lower toxicity compared to conventional compositions and tanning methods based on aldehydic tanning agents. Furthermore, improved penetration of the tanning agents into deeper layers of the hide and/or the pelt is possible, so that particularly homogeneous tanning is achieved.

Abstract: A composition including an acetal of an aldehydic tanning agent for tanning hides and/or pelts, as well as a method for tanning hides and/or pelts in order to produce leather, wherein an acetal of an aldehydic tanning agent is used. By reducing the pH, the aldehydic tanning agent can be released, whereby a tanning step is initiated. The composition according to the invention and the method according to the invention are characterized by lower toxicity compared to conventional compositions and tanning methods based on aldehydic tanning agents. Furthermore, improved penetration of the tanning agents into deeper layers of the hide and/or the pelt is possible, so that particularly homogeneous tanning is achieved.

Abstract: A composition including an acetal of an aldehydic tanning agent for tanning hides and/or pelts, as well as a method for tanning hides and/or pelts in order to produce leather, wherein an acetal of an aldehydic tanning agent is used. By reducing the pH, the aldehydic tanning agent can be released, whereby a tanning step is initiated. The composition and the method are characterized by lower toxicity compared to conventional compositions and tanning methods based on aldehydic tanning agents. Furthermore, improved penetration of the tanning agents into deeper layers of the hide and/or the pelt is possible, so that particularly homogeneous tanning is achieved.

Abstract: The present invention is directed to a process for retanning leather comprising the steps of: a) providing tanned or pre-tanned leather b) treating the tanned leather of step a) with a composition comprising hollow microspheres, preferably as an aqueous composition, the hollow microspheres have a true density of from 0.01 to 0.10 g/cm3 (25° C.) and/or a bulk density of the dry powder of 0.005 to 0.06 g/cm3 (25° C.), c) drying, whereby the temperature of the leather during drying does not exceed 75° C. as well as to leather obtained by said process.

Abstract: The present invention is directed to a process for retanning leather comprising the steps of: a) providing tanned or pre-tanned leather b) treating the tanned leather of step a) with a composition comprising hollow microspheres, preferably as an aqueous composition, the hollow microspheres have a true density of from 0.01 to 0.10 g/cm3 (25° C.) and/or a bulk density of the dry powder of 0.005 to 0.06 g/cm3 (25° C.), c) drying, whereby the temperature of the leather during drying does not exceed 75° C. as well as to leather obtained by said process.

Abstract: D-Isoascorbic acid or one of its salts, as such or as a constituent of a liquid or solid formulation, is an effective agent for reducing the amount of Cr(VI) compounds in leathers tanned with Cr(III) salts by treatment of the leather in an aqueous liquor after tanning or finishing or of a commodity article with an aqueous solution.

Abstract: D-Isoascorbic acid or one of its salts, as such or as a constituent of a liquid or solid formulation, is an effective agent for reducing the amount of Cr(VI) compounds in leathers tanned with Cr(III) salts by treatment of the leather in an aqueous liquor after tanning or finishing or of a commodity article with an aqueous solution.

Abstract: Compositions comprising a) 5 to 50% by weight of an aliphatic dialdehyde having 2 to 10 carbon atoms; b) 2-5 to 20% by weight of at least one reductive saccharide having a dextrose equivalent of 10 to 100; c) 2.5 to 20% by weight of at least one water-soluble, optionally monoetherified polyoxaalkylene glycol having a molecular weight of more than 100 and not more than 2000; and d) 90 to 10% by weight of water, 0.05 to 0.19 mole of the components b) and c) being added per mole of the component a), outstandingly suitable for the pretanning of pelts and subsequent production of leathers free of heavy metals.

Abstract: Compositions comprising a mineral oil or wax and a liquid polysiloxane substituted by functional groups, an anionic surfactant and additionally a molecular mono- or polycarboxylic acid and optionally any emulsifiable, hydrophilic or amphiphilic polymer comprising carboxyl groups are outstanding water repellents for leather, furskins, textiles and fibrous materials.

Abstract: Tanned leather is (a) pretreated in an aqueous and alkaline medium either with ammonia, primary amines or a mixture of ammonia and primary amines and then with a polyfunctional organic compound containing at least one aldehyde group as a functional group, or (b) in an aqueous and acidic medium with a polyfunctional organic compound and then ammonia, primary amines or a mixture of ammonia and primary amines, and (c) then dyed in an aqueous and alkaline medium with a water-soluble dye containing at least one functional group which is capable of reacting with one of the functional groups of the organic compound, forming a covalent bond. A tanned and dyed leather is obtainable with a high color intensity, outstanding wet fastness and excellent grain tightness, wherein the dye is permanently and covalently bonded to the leather via a bridging group, preferably in the region of the surface, and the bridging group is essentially bonded to the leather via —N?CH— groups.

Abstract: There is disclosed an aqueous formulation for pretanning leather, which formulation comprises (a) a reductive saccharide having a dextrose equivalent of 10 to 100, and (b) an aliphatic dialdehyde containing 2 to 8 carbon atoms, and which is devoid of mineral salts. The leather treated with the novel aqueous composition (wet white leather) is eminently suitable for further processing, especially for the manufacture of leathers which are devoid of heavy metals.

Abstract: Compositions for the simultaneous retanning and fatliquoring of leather are described which may include further leather treatment agents as well.