The method of tanning hides
(57) Abstract:The inventive skin is treated with a solution of tannic composition with the following components concentration, g/l: chrome tanning agent in terms of Cr2O310; poly-2-oxypropylene chloride 0,005 - 0,01. table 2. The invention relates to chemical treatment of skins, and tanned hides, and is intended for use in the leather industry for tanning skins from Astrakhan, sheepskin, goat and other skins.There is a method of tanning skins using tanning composition on the basis of the reaction products of Polyoxymethylene with a secondary amine and alcohol, and after the reaction in the form of tertiary amino groups and ether groups .There is a method of tanning skins using tanning composition on the basis of salts of trivalent chromium and a polycarboxylic acid, after reaction in the form of ether, urethane or amide .Known methods of tanning skins have some drawbacks, namely the duration of the tanning process due to the absence in the structure of the active hydroxyl and ionogenic groups, as well as trudnodokazuemosti composition due to the formation of new substances in pria physico-mechanical characteristics of hides, skins, in the known method in the solution of the tanning composition on the basis of chrome tanning agent and a polymeric agent as a polymeric agent used polyhexamethylenediamine chloride with the concentration of the components in the following ratios, l:
Chrome tanning agent in terms of Cr2O310
Poly-2-oxoprop - Ammoni chloride 0,005-0,01
Introduction to tanning composition of the polymeric agent containing in its structure the active hydroxyl and ionogenic groups leads to the formation of khromosomnymi compounds a large number of cross-linking, "cross-linking" molecular chains of collagen. Tanning khromosomnymi compounds increases the speed of diffusion tanning particles of tanning solution and increases their content in the material, which leads to the reduction of the process time tanning and improvement of physical-mechanical characteristics of the skin.P R I m e R 1. The polymeric agent is prepared as follows. In a three-neck flask pour 40,52 ml (0,595 mol) of 25% aqueous ammonia and with vigorous stirring to a solution of ammonia in small portions over 5-10 min add 25 ml (0,305 mol) of epichlorohydrin. The reaction mixture is heated to 80-90aboutC. After cooling is giving 1 h at 35aboutTo obtain product is a light brown color. Received the product a few times treated with acetone or isopropyl alcohol to remove unreacted substances. Yield, % 95 Content of chlorine % 26
bone of 0.5% solution in water, DL/g 0,39; Exchange capacity of 0.1 n AgNO3, mg-equiv/g of 4,9;
Given viscosity in 0.1 KCl, DL/g 0,09
In the prepared chromic extract volume of 100 l containing 10 g/l of chromium (III) oxide at room temperature add a freshly prepared solution of poly-2-oxypropylene chloride containing 0.5 g of polymer. Intensively mix the components of the solution for 15 min and the process of tanning, which ends in 6 hours after the tanning process the samples processed according to the current plant technology and then the prepared samples are subjected to physical and mechanical tests. Check the end of the tanning process is carried out by sensing the temperature of the welding skins (PL.1).Karakul skins have the following physical characteristics: tensile strength, EASC/mm20,96; elongation, %, 32.P R I m m e R 2. In the prepared chromic extract volume of 100 l containing the example 1, containing 1 g of polymer, and the process of tanning samples Karakul skins, which ends after 6 hours the End of the tanning process and the subsequent processing is carried out as indicated in example 1.Karakul skins have the following physical characteristics: tensile strength, kgf/mm2, 0,90; elongation, %, 29.The study of the speed of penetration of the tanning agents into the tissue of the skin showed that in the known method the maximum value of the chromium oxide is reached after 12 h, when used in tanning solution polymer agent, in the proportions stated in the proposed method, the maximum value of the chromium oxide is achieved after 5 h, which indicates the acceleration of the process of tanning is more than 2 times due to the complexation of polymer chains oxide of chromium.The results of physico-mechanical tests 25 samples Karakul skins subjected to the process of tanning on the proposed method are presented in table.2.As can be seen from the above experiments, technical and economic efficiency of the invention is provided by the intensification of the process of tanning, improvement of physico-mechanical characteristics of the skin. P IS P> The METHOD of TANNING hides and SKINS by treating them with a solution of tannic structure on the basis of chrome tanning agent and a polymeric agent, characterized in that the polymeric agent is used poly-2-oxypropylene chloride with the following components concentration, g/l:
Chrome tanning agent in terms of Cr2O3- 10
Poly-2-oxypropylene chloride - 0,005 - 0,01
FIELD: leather industry.
SUBSTANCE: method comprises pickling, tanning, and neutralizing the semifinished item. During pickling and subsequent tanning, the picking liquid is provided with acetate sodium in amount of 0.2-0.5 % and, then, chromic tanner in amount of 1.5-1.8%. The tanning is carried out until the pH of the solution reaches 4.2-4.4.
EFFECT: enhanced quality of tanning.
FIELD: leather industry.
SUBSTANCE: method involves pickling leather depilated hide with sodium chloride and sulfuric acid, addition of chrome tanning agent to the same bath in its consumption 0.5-0.6% of depilated hide mass as measured for chrome oxide, and chrome-plating is carried out for 2-4 h. Aliphatic dialdehyde is added to same bath in the concentration 3-6% of depilated hide mass, and treatment is carried out for 2-3 h wherein glyoxal or glutaraldehyde is used as dialdehyde. Invention provides enhancing thermal stability and strength properties of leather and can be used in tanning leathers for different designation and assortment.
EFFECT: improved tanning method.
2 cl, 1 tbl, 9 ex
FIELD: chemistry, hide tanning.
SUBSTANCE: method relates to tanning hides and can be used in the leather industry. Animal hides are treated with a solution of chrome tanning agent with addition of an activating organic agent in form of aminocapronic acid at concentration of 8-12 g/l.
EFFECT: improved strength properties of hides and environmentally safe method.
FIELD: process engineering, leather industry.
SUBSTANCE: after hide pickling, skins are sent to ageing. Then fur leather layer is processed by priming solution comprising chrome tanning agent with concentration of 9-18 g/l per chrome oxide. Skins are aged to effect main paste-tanning-stuffing and ageing.
EFFECT: improved organoleptic properties of fur skins, ie broach, softness, elasticity and higher tensile strength.
2 tbl, 3 ex
SUBSTANCE: method involves chrome tanning and post-tanning a semi-finished product through chrome tanning in the presence of a product of reaction of 3-aminopropyltriethoxysilane and glycidylmethacrylate in molar ratio of 1:2 and consumption of the chrome tanning agent and reaction product of 3-4% and 2-3% of the weight of the semi-finished product respectively. Neutralisation and hydrophobisation with a polymer tanning agent are then carried out for 30-40 minutes with consumption of the tanning agent equal to 8-10% of the weight of the semi-finished product. After that dyeing is carried out in the presence of a synthetic tanning agent in amount of 3-4% of the weight of the semi-finished product. Post-tanning is carried out with a plant-material tanning agent and the semi-finished product is also treated for 20-30 minutes with a product of reacting hexamethylenediamine with phosphoric acid and urea in the presence of glycerin in molar ratio of 1:3:3:0.5 respectively, in amount of 3-4% of the weight of the semi-finished product and for 20-30 minutes with organic acid in amount of 0.5-1.0% of the weight of the semi-finished product. Further, the semi-finished product undergoes greasing and re-treated for 40-50 minutes with a product of reacting hexamethylenediamine with phosphoric acid and urea in the presence of glycerin in molar ratio of 1:3:3:0.5 and consumption of 7-8% of the weight of the semi-finished product, volume ratio of 0.8-1.0 and temperature of 20-22°C. Hydrophobisation with a polymer tanning agent, dyeing in the presence of a synthetic tanning agent, post-tanning with a plant-material tanning agent, further treatment with a product of reacting hexamethylenediamine with phoshoric acid and urea in the presence of glycerin in the said molar ratio and with organic acid is carried out in one bath. Separation and drying are carried out after all operations.
EFFECT: higher water-, fungus- and heat-resistance of leather under high moisture and temperature conditions, and wide range of special types of leather.
2 cl, 3 tbl, 5 ex
SUBSTANCE: invention refers to general chemical engineering and is applicable to measure a mass transfer rate of various materials into capillary-porous bodies of leather and fur industries, wood processing, construction materials manufacturing, textile industry, etc. The method consists in the fact that capillary-porous body samples, e.g. leather, are filled with chemicals; this process involves sectioning specimens to be analysed to a chemical penetration speed as shown by a penetration depth per a unit of time. The capillary-porous bodies, e.g. thickness leather specimens are fixed in a retainer of a contrast colour, placed on a surface of a contrast colour and recorded by means of a remote digital camera fixed on a Tripod. The digital camera is provided with extension rings for macrophotography and a ring flash; a sample image is uploaded into a software programme for digital processing of colour images to generate a chemical penetration histogram into the thickness of the capillary-porous body, which is used to measure an area of the stained specimen, whereas a speed is calculated by the area of the stained specimen per a unit of time.
EFFECT: invention provides the more effective measurement of mass transfer speed in the capillary-porous bodies, and reducing the length of the process.
29 dwg, 6 tbl
FIELD: tannery industry, in particular method for syntan (synthetic tanning material) production.
SUBSTANCE: claimed method includes diphenolepropane sulgation and condensation with formaldehyde followed by acidifying with sulfuric acid. Formed product is dispersed in lignosulfates containing 0.5-1.5 % of aluminum sulfate as calculated to aluminum oxide.
EFFECT: syntans with stable content of tanned materials: environmentally friendly and economical process.
FIELD: chemistry of polymers, leather industry, chemical technology.
SUBSTANCE: invention relates to a method for preparing polymeric products that are used in processes for dressing leather or fur, in treatment and disinfection of natural and sewage waters. Method for preparing polymeric products involves the hydroxymethylation reaction of polyhexamethylene guanidine chloride with formaldehyde and arylation reaction of prepared product with aromatic compound comprising o-amino- or o-hydroxy-groups. The hydroxymethylation reaction is carried out in the presence of acetic acid or formic acid up to formation of trimethylol derivative of polyhexamethylene guanidine chloride. In some cases the arylation product is subjected for complex formation with transient metal salt or azo-coupling reaction with diazonium salt taken among group including sulfanilic acid, naphthionic acid, j-naphthyls, p-nitroaniline, 2,6-dichloro-4-nitroaniline. Invention provides simplifying, accelerating and enhancing the effectiveness of process in dressing leathers with derivatives of polyhexamethylene guanidine showing tanning effect, staining properties, flocculating capacity and high antibacterial activity.
EFFECT: improved preparing method.
3 cl, 1 tbl, 9 ex
SUBSTANCE: invention relates to graft polymers based on polysaccharides and polypeptides. Graft polymer based on polysaccharides and polypeptides or respective derivatives thereof are obtained by free-radical polymerisation of A) a monomer selected from following, or a mixture of following monomers: (a) from 20 to 100 wt% acrylic acid or methacrylic acid, or mixture thereof, or salts thereof with an alkali metal, alkali-earth metal or ammonium, (b) from 0 to 80 wt% other monoethylenically unsaturated monomers, which can be copolymerised with monomer (a) and (c) from 0 to 5 wt% monomers containing per molecule at least 2 ethylenically unsaturated unconjugated double bonds in presence of B1) polysaccharides subjected to oxidative, hydrolytic or enzymatic decomposition, oxidised polysaccharides subjected to hydrolytic decomposition or subjected to enzymatic decomposition, or chemically modified decomposed products, chemically modified mono-, oligo-or polysaccharides, or mixtures of said compounds and B2) polypeptides subjected to hydrolytic or enzymatic decomposition and optionally chemically modified polypeptides, or mixtures of said compounds, with weight ratio A:(B1+B2) ranging from 60:40 to 1:99 and B1:B2 from 97:3 to 3:97. Also disclosed is a method of producing graft polymers, method of tanning leather, and tanned leather.
EFFECT: wider range of polymers for various types of tanning.
7 cl, 18 ex