摘要:
Tanning agents can be prepared by reacting at least one aldehyde of formula I, with at least one further identical or different aldehyde of formula I, where Z is a single chemical bond, unsubstituted or substituted C1-C12-alkylene, unsubstituted or substituted C5-C12-cycloalkylene or unsubstituted or substituted C6-C14-arylene, the reaction being carried out in the presence of an acidic catalyst and in the presence of at least one further carbonyl compound of formula II where R1 to R4, independently of one another, are hydrogen, unsubstituted or substituted C1-C12-alkyl, unsubstituted or substituted C3-C12-cycloalkyl, unsubstituted or substituted C7-C13-aralkyl or unsubstituted or substituted C6-C14-aryl, with the proviso that, where Z is a single chemical bond or a radical without a-hydrogen atoms, at least one further aldehyde of the formula I, in which Z contains α-hydrogen atoms, or at least one further carbonyl compound of formula II is present.
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.
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:
The present invention relates to C4–C6-polymercaptopolyols as regulators in the free-radically initiated solution and precipitation polymerization of ethylenically unsaturated monomers.
摘要:
The invention relates to a tanning agent that is produced by reacting at least one aldehyde of general formula (I) with at least another identical or different aldehyde of formula (I), wherein the variables are defined as follows: Z is a single chemical bond, an optionally substituted C1-C12-alkyl, an optionally substituted C5-C12-cycloalkyl or an optionally substituted C6-C14-aryl, wherein the reaction is carried out in the presence of an acid catalyst and optionally in the presence of at least another carbonyl compound of formula (II), R1 to R4 represent, independent of one another, hydrogen, optionally substituted C1-C12-allyl, optionally substituted C3-C12-cycloalkyl, optionally substituted C7-C13-aralkyl or optionally substituted C6-C14-aryl, provided that at least another aldehyde of formula (I) in which the radical of Z contains α hydrogen atoms or at least another carbonyl compound of formula (I) is present when Z is a single chemical bond or a radical without any hydrogen atoms. The invention also relates to a method for the production of said tanning agent, to the utilization thereof as curing agent, particularly for pretannage, tannage or retannage of animal skins using the inventive tanning agents. The invention further relates to a powder active agent containing one or more of said inventive tanning agents, to a method for the production of said powder active agents and to the use thereof as curing agent and to leather produced using the inventive tanning agents or the inventive method.
摘要:
Adducts are obtained by reacting carbonyl compounds of the formula I where R1 and R2 are as defined, with cyclic compounds of the formula II where X is selected from oxygen, sulfur and N—R8, R3-R8 are as defined, and n is an integer from 1 to 4, which adducts are useful as tanning agents and preservatives.
摘要:
A formulation for use in chrome-free or chrome tanning is proposed, comprising a clay mineral which, after vigorous stirring for 30 minutes in water at 50° C., has a number average particle diameter of less than 2 μm or a bimodal 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, the amount of the first, finely divided fraction being from 10 to 90% by weight, and one or more substances from one or more of the following groups: organic polymers, aldehyde tanning agents, sulfone tanning agents, resin tanning agents, phenol tanning agents, fatliquoring agents, vegetable tanning agents, dyes and pigments.
摘要:
A formulation for use in chrome-free or chrome tanning is proposed, comprising a clay mineral which, after vigorous stirring for 30 minutes in water at 50° C., has a number average particle diameter of less than 2 μm or a bimodal 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, the amount of the first, finely divided fraction being from 10 to 90% by weight, and one or more substances from one or more of the following groups: organic polymers, aldehyde tanning agents, sulfone tanning agents, resin tanning agents, phenol tanning agents, fatliquoring agents, vegetable tanning agents, dyes and pigments.
摘要:
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.
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.