摘要:
The soaking of hides and skins is enzymatically assisted in a method using an aqueous float having a pH from 9 to 11 which containsA) a lipase having an activity optimum in the pH region from 9 to 11,B) a protease with activity in the pH region from 9 to 11, andC) a surface active agent.
摘要:
A method for the wet degreasing of raw hides and skins, pelts, and wet blues under the conditions of enzymatic bating, wherein enzymatic bating of the hide stock is carried out with proteolytic enzymes in the presence of synthetic surface active substances, for example, a mixture of a non-ionic emulsifier and anionic emulsifier.
摘要:
A method and a device for converting and separating substances dissolved in a carrier fluid, more particularly proteides or proteins, by adding and mixing with an agent, e.g. enzymes, which brings about the chemical reaction or the build-up or breakdown of the molecules of the substances and causes them to precipitate. In addition these substances are mixed and come to an accelerated reaction with the agent in at least one circuit flow through a jet immersion reactor while a gas is supplied intensively thereto before froth flotation of the precipitated substances is carried out after adding means assisting flotation.
摘要:
An oligomerized polyorganosiloxane cocondensate which may be obtained, in part, by mixing an water-soluble amino-functional organosilane represented with at least one of the followoing: a fluoro-functional organosilane, an organosilane, and an organosilane. The cocondensate may be used, for example, in a method of treating surfaces.
摘要:
A method for preparing unhaired hides ready for tanning from hides and skins using proteolytic and lipolytic enzymes in the beamhouse, whereby in at least one of the partial steps of the beamhouse consisting of a) liming in the pH range 11.5-14 and b) bating in the pH range 5-11.5, alkaline lipases (E.C.3.1.3.) having an activity optimum in the pH range 9-11 are added to the aqueous floats corresponding to these partial steps.
摘要:
Tanning agents containing a complex formed between chromium ions and an acrylate or methacrylate polymer and further including an organically bound thio group present in said polymer or in a mercapto compound added to the tanning agents, and methods for pickling, tanning, and retanning skins and hides with such tanning agents.
摘要:
A process for liming skins and hides with preservation and separation of the hair, including the following successive steps:(A) a soaking step in a aqueous liquor containing a surfactant;(B) an incubation step in an aqueous liquor free of inorganic sulfur but containing hydrotropes and organic sulfur compounds as unhairing agents;(C) an step for immunization of the hair at a pH between 10 and 14;(D) a hair loosening step in which inorganic sulfide is added to the float;(E) a separation step in which the hair is separated from the skins and hides; and(F) a liming step in which the pelts so obtained are limed in an aqueous alkaline liquor comprising liming aids.
摘要:
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.1; C) use of degreasing agents of the formula C.1 for degreasing pelts, hides or other intermediate stages and semifinished products in leather production, n and R16 to R21 having the meanings stated in the description; D) tanning with the use of a tanning agent which can be prepared by reacting at least one aldehyde of the formula D.1, with at least one further identical or different aldehyde of the formula D.1 in the presence of an acidic catalyst and optionally in the presence of at least one further carbonyl compound of the formula D.2 Z and R22 to R25 having the meanings stated in the description, with the proviso that, when Z corresponds to a single chemical bond or a radical without α-hydrogen atoms, at least one further aldehyde of the formula D.1, in which Z contains α-hydrogen atoms, or at least one further carbonyl compound of the formula D.2 is present.
摘要:
A semifinished leather product is produced from an animal hide by pretanning with the use of a chromium-free tanning agent and of a clay mineral which, after stirring for 30 minutes in water at 50° C. at a circumferential rotor speed of from 5 to 25 m/s, has a number average particle diameter of less than 2 μm or a bimodal particle size distribution with a first, finely divided fraction whose number average particle diameter is less than 0.5 μm and a second, coarser fraction whose number average particle diameter is less than 5 μm, determined in each case by the method according to ISO 13320-1, by combined laser light diffraction and light scattering, a proportion of the first, finely divided fraction being from 10 to 90% by weight, and drying of the pretanned animal hide to a water content of from 5 to 45% based on the total weight of the semifinished leather product.
摘要:
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.