145results about How to "Increase shrinkage temperature" patented technology

The invention discloses a dual-purpose modification process for native breed sheepskin leather. The process sequentially comprises the following steps of processing native breed sheepskin semi-finished products: (1) classifying skin; (2) returning water; (3) soaking; (4) softening; (5) pickling; (6) performing chromium aluminum tanning; (7) performing tanning post-processing; (8) performing chrome retanning; (9) performing chrome retanning before dyeing; and (10) dyeing. According to the dual purpose modification process, commercially available native breed semi-finished skin (namely white skin) is processed, and the native breed semi-finished skin is tanned by increasing aldehyde aluminum tanning particularly, so that the extensibility of the native breed sheepskin can be effectively improved, the problem of dyeing defects is solved, and the uniformity in the post dyeing is ensured. The dual purpose modification process is matched with other steps and appropriate additives, and each additive is added according to reasonable additive amount, so that the final products have good handfeeling, high tearing resistance and high fullness, and the quality of the native breed sheepskin leather is greatly improved.

The invention discloses a method for preparing a modified starch tanning agent, comprising the following steps of: firstly, degrading corn starch; in the presence of HRP (Horse Radish Peroxidase)/ hydrogen peroxide (H2O2), grafting and modifying the degraded starch with sulfanilic acid, gallic acid and nekal; and then oxidizing the grafted starch with periodic acid. The invention has the innovation points that a nekal structure unit is introduced in the starch structure so as to improve the permeation wetting function of the modified starch tanning agent; the gallic acid structure unit is introduced to improve the tanning properties of the modified starch tanning agent, the sulfanilic acid is introduced to increase the dispersivity of the modified starch tanning agent, and dialdehyde action is used for improving the tanning properties of the modified starch tanning agent. The preparation method of the invention is peculiar and practical, and the obtained tanning agent is an environmentally-friendly leather tanning agent and is suitable for primary tanning and retanning. The shrinkage temperature (Ts) of pickled leather after primary tanning can be improved to 75-80 DEG C; and the retanned product has the advantages of wash resistance, high absorption rate on dyes and fatting agents and the like, is soft and plump.

The invention relates to a water-soluble octacarboxyl silsesquioxane tanning agent prepared by mercaptan-alkene click chemistry process and a method thereof. The method comprises the following steps: firstly preparing octavinyl-polyhedral oligomeric silsesquioxane by using vinyl trimethoxy silane through a hydrolysis condensation method, then reacting octavinyl-polyhedral oligomeric silsesquioxane with mercaptoacetic acid under the condition with photoinitiators and irradiation of ultraviolet lamps to obtain the water-soluble octacarboxyl silsesquioxane tanning agent. The water-soluble octacarboxyl silsesquioxane tanning agent is high in yield and high in purity; the reaction process is easy to control and operate; the reaction time is short; the tanning agent has a certain tanning effect; when the tanning agent cooperating with 2% chromium powder is applied to a tanning process of pickled goat skin, the shrinkage temperature of the tanned crust leather is increased by 35 DEG C; the thickening rate reaches about 67%.

The invention relates to a technical field of tanning chemistry and engineering, and provides a production technology for improving the smoothness and fineness of the grain surface of leather. According to the production technology, the grain surface of the cow leather obtained through the production technology is smooth, fine, tiny in pores, attractive, elegant, high in product grade, good in physical and mechanical properties, soft and comfortable in hand feeling and good in resilience, and in addition, the production technology is simple and easy to realize, appropriate in production cost and suitable for mass production and use. The production technology for improving the smoothness and fineness of the grain surface of the leather sequentially comprises the following steps of carryingout splitting on limed hide, carrying out deliming, softening and pickling, carrying out tanning, carrying out wringing and shaving, carrying out softening, carrying out retannin, carrying out neutralizing, carrying out filling, carrying out greasing, carrying out overdyeing and carrying out post treatment, wherein the tanning process adopts an aluminum-contained multi-metal tanning agent and a chrome tanning agent for co-tanning, the retanning process adopts a liquid betel nut tannin extract, an aldehyde tanning agent, an amphoteric synthetic tanning agent and the aluminum-contained multi-metal tanning agent for retanning, and the filling process adopts a micromolecular acrylic resin retanning agent, a phenolic condensation compound, a naphthalene sulfonic acid condensation compound, a synthetic greasing agent, sulfonated natural oil and a plant tannin extract for filling.

The invention relates to a tanning method by using an improved-structure chromium-free retanning agent, belonging to the technical field of leather treatment. In order to overcome the defects of severe chromium pollution, low shrinkage temperature and low setting point in the retanning process, the invention provides a tanning method by using an improved-structure chromium-free retanning agent. The method comprises the following steps: adding shaving leather into a rotating drum, adding 100-150 wt% of water, regulating the temperature to 25-30 DEG C, adding 1.5-2.0 wt% of coordination polymerization inhibitor, and rotating for 10-30 minutes; regulating the pH value of the bath to at most 3.5, and rotating for 60-90 minutes; adding 1.0-2.0 wt% of tanning-assisting tannin, and rotating for 90-120 minutes; adding a non-chromium metal composite tanning agent and 0.2-0.4 wt% of alkali extractor to perform alkali extraction; and heating to 38-40 DEG C to perform treatment, and carrying out after-treatment to obtain the finished leather product. The tanning agent has the advantages of high setting point and high shrinkage temperature; and the method effectively controls the total chromium content in the wastewater and sludge.

This invention provides an ecological tanning method. The method comprises: pre-tanning with aldehyde tanning agent, tanning with tetrahydroxymethyl phosphonium salt, and then adding collagen to enhance the bonding of the tanning agents. The method utilizes the reaction among aldehyde tanning agent, tetrahydroxymethyl phosphonium salt and collagen to enhance the bonding of the tanning agents as well as increase the shinkage temperature. Besides, the addition of collagen can improve the comprehensive properties of leather and reduce the aldehyde content in leather. The method can be used to replace chrome tannage, thus can avoid the harm of chrome salt to human body and environment.

The invention relates to a tanning method for tanning sheepskin clothing leather by a hyperbranched polymer-aluminum salt tanning agent. Current chrome free tanning agents cannot completely replace chrome tanning agents for realizing better anti-hydrothermal stability of leather. The tanning method provided by the invention comprises the following steps of: pre-treating; pickling; tanning; degreasing; retanning; neutralizing; filling; oiling and drying acidic leather. The preparation method of the hyperbranched polymer-aluminum salt tanning agent used in the tanning process comprises the following steps of: mixing diethanol amine and methyl acrylate, and adding methanol to obtain an AB2 type monomer; carrying out reaction of the AB2 type monomer with trimethylolpropane, and adding para-toluenesulfonic acid for temperature rising reaction to prepare hydroxyl-terminated hyperbranched polymer; carrying out reaction of the hydroxyl-terminated hyperbranched polymer with maleic anhydride, adding para-toluenesulfonic acid to prepare an intermediate of an aqueous liquor of the hydroxyl-terminated hyperbranched polymer, and mixing and reacting the intermediate aqueous liquor with analytically pure analytically pure at normal temperature to obtain the hyperbranched polymer-aluminum salt tanning agent. The method provided by the invention is higher in shrinkage temperature and can replace the conventional chrome tanning method, so that chrome tanning pollution is reduced.

The invention relates to an all-component wide-distribution organic polyaldehyde tanning agent and a preparation method thereof. The preparation method is characterized in that firstly, periodate is utilized to perform hydroformylation on polysaccharide and derivatives thereof under a proper condition, so as to retain all components of hydroformylated polysaccharide; secondly, an inorganic reducing agent is utilized to efficiently convert an iodine-containing compound into solid molecular iodine, and the solid molecular iodine is filtered and recycled; and finally, the hydroformylation product filtrate is subjected to heat treatment, so that the residual iodide is separated out in the form of steam, further absorbed by a NaOH solution and recycled, and the all-component wide-distribution organic polyaldehyde tanning agent is obtained. According to the all-component wide-distribution organic polyaldehyde tanning agent and the preparation method thereof, the technical problems that the conventional hydroformylated polysaccharide tanning agent is too narrow in molecular weight distribution and poor in tanning property, or contains the iodine-containing compound and affects the overall performance of leather after tanning are solved; besides, the prepared tanning agent retains all components of hydroformylated polysaccharide, the molecular weight distribution is wide, the shrinkage temperature of leather/fur after tannage can reach 85-90 DEG C, and the treated leather is pure white, full and soft.

The invention discloses a leather softening compound enzyme with acid proteases and a method for preparing the leather softening compound enzyme. The leather softening compound enzyme and the method have the advantages that the leather softening compound enzyme is mainly made of the high-activity acid proteases with abundant plant proteases and microorganism proteases, mould culture, acid lipase, non-ionic surfactants, plant extract, antioxidants, protective agents, activators and the like are scientifically compounded, accordingly, the compound enzyme is provided with complete enzyme systems, is stable in activity and high in efficacy, permeability and degreasing capacity and can act mildly and moderately, the hand feel and physical and mechanical properties of crust leather can be obviously improved, the bare weight of the crust leather can be obviously increased, and the shrinkage temperatures of the crust leather of raw hide of wet-blue leather of different animals can be increased by 9-14 DEG C; the porosity of the crust leather can be improved by 7.85-10.96%; the breathability of the crust leather can be improved by 41.0-50.1 mL/cm<2>hr; the tensile strength of the crust leather can be improved by 6.51-7.47 N/mm<2>; the tear strength of the crust leather can be improved by 5.28-20 N/mm; the elongation of the crust leather can be improved by 4.8-8.7%; the quality of products can be greatly improved, and the production cost can be reduced.

Disclosed is a preparation method of a chromium-free tanning agent. The preparation method includes following steps: adding a mixed solution into a solution and carrying out an acidification reaction with stirring to prepare a silicic acid solution, wherein the mixed solution contains a silicon-containing compound and a solvent and the solution is a mixture of an inorganic acid, an organic acid and a solvent, dissolving an aluminium-containing compound and adding the aluminium-containing compound to the prepared silicic acid solution, carrying out a spray drying process to obtain a white powdery chromium-free tanning agent product and drying and preserving the product. The tanning agent is free of harmful substances such as hexavalent chromium, formaldehyde and the like, is excellent in environmental-friendly performance, is substantially harmless to human body, is simple and convenient in production process, is low in cost and is suitable for large-scale production. [0]

The invention provides a leather tanning method. The method comprises the steps of a, pretreatment before tanning, dry animal skin is subject to soaking, meat removal, degreasing, hair removal, splitting and acid maceration, and raw hide is obtained; b, tannin extract tanning, wherein the raw hide is put into a rotary drum, and water and a plant tanning agent are added for plant tanning; c, aluminum tanning, wherein leather is put into the rotary drum, tanning liquid is added, and after tanning, baking soda and sodium acetate are used for neutralizing; d, aftertreatment, wherein through the above steps, finished leather is manufactured. A plant tanning agent and aluminum tanning agent composite tanning method is used for replacing a chromium metal tanning agent for tanning, and on the basis of keeping the tanning effect, the harm of chromium salt to the environment and the human body is removed.

The invention relates to the technical field of leather manufacturing, and provides an ecological environment-friendly vegetable tanning yellow cattle upper leather production process. According to the ecological environment-friendly vegetable tanning yellow cattle upper leather production process, an organic pre-tanning agent is used for pretreating softened leather, the tanning agent based on avegetable tanning agent is used for tanning, wherein the vegetable tanning agent is mainly a condensed vegetable tanning agent, and then an aldehyde tanning agent is combined for retanning; the vegetable tanning agent, collagen, the aldehyde tanning agent can form cross-linking to produce a vegetable-aldehyde synergistic tanning effect, the fixation effect of the vegetable tanning agent is improved to improve the absorptivity of the vegetable tanning agent, the washing resistance, organic agent resistance performance and shrinkage temperature of the obtained green leather are improved, and thedistribution of vegetable tanning agent on each layer of green leather is more uniform; and the green leather has fine grain size, good compactness, good softness, good fullness and good elasticity,and accords with the characteristics of upper leather products.

The invention relates to a preparation method of starch and sulfomethyl phenol graft copolymer leather synthesis tanning agent, the method comprises the following steps: reacting sodium bisulfite with sodium sulfite and formaldehyde, to prepare sodium hydroxymethanesulphonate, then performing a sulfomethylation of hydroxymethyl sulfonate and phenol under the alkaline condition, to prepare a sulfomethyl phenol solution, finally, mixing the sulphur methyland phenol solution with enzymatic degradated starch, regulating the pH value of the solution by sodium bicarbonate, performing a graft copolymerization reaction of starch and sulphur methyland phenol under the catalytic effect of horseradish peroxidase, to obtain the starch graft copolymer leather synthesis tanning agent. The obtained product has the advantages of moderate relative molecular mass, good permeability and high absorption, and is a high-molecular tanning agent with no pollution and green performance. The preparation method of the present invention has an unique synthesizing preparation technology, the shrinkage temperature can reach at 78 DEG C when the obtained synthesis tanning agent is taken as a main tanning agent, the thickening rate of the leather can reach at 28% when the obtained synthesis tanning agent is used for retanning, thereby the leather possesses soft handfeel. The agent can be used as the leather tanning agent with green environmental protection performance.

The invention provides a preparation method of high-performance carbon nanotube modified chrome tanning agent, which comprises the following steps of: after mixing a carbon nanotube with an acid solution, and ultrasonically processing the mixture to prepare a suspension; then, heating, condensing, refluxing, repeatedly washing and centrifugally separating until the pH value becomes neutral; subsequently, after dissolving dichromate in water, slowly adding sulfuric acid and the treated carbon nanotube; ultrasonically processing to prepare a stable suspension; taking glucose and adding water to dissolve the glucose; dropwise adding the water solution of glucose into the suspension containing dichromate while stirring so as to produce a carbon nanotube modified chrome tanning liquid in-situ; and finally, settling and placing for long time. The chrome tanning agent enhances the bonding force of chrome, increases the quality and the properties of leather, is friendly to environment, reduces pollution and decreases resource waste.

The invention relates to the technical field of tanning waste source utilization and provides a method for preparing a semi-chrome tanning addition agent through waste chrome shavings and an application method of the semi-chrome tanning addition agent. Waste chrome shaving resources can be effectively converted into the semi-chrome tanning addition agent so as to be reused in the leather production and preparation processes, and the dual economic benefits of environment-friendly tanning and reduction of tanning cost are achieved. According to the method for preparing the semi-chrome tanning addition agent through the waste chrome shavings, collagen hydrolysate liquor is obtained through acid hydrolysis of the waste chrome shavings and then modified through unsaturated dicarboxylic acid andtetrakis hydroxymethyl phosphonium salt, the semi-chrome tanning addition agent is obtained, carboxyl functional groups of collagens in the semi-chrome tanning addition agent are increased, the jointpoints of proteins in the obtained semi-chrome tanning addition agent and a chrome tanning agent are increased, thus, combination and absorption of leather treated through the obtained semi-chrome tanning addition agent and the chrome tanning agent are promoted, meanwhile, the obtained semi-chrome tanning addition agent has certain tanning performance and filling property, the crust leather contraction temperature can be increased, and the fullness, elasticity and grain surface flatness of crust leather are improved.

The invention relates to a preparation method of a formaldehyde-free leather synthetic tanning agent by enzymatic synthesis. Firstly, p-hydroxybenzoic acid and poly hexanediol are reacted to produce ester, then p-hydroxybenzoic acid macrogol ester, p-hydroxybenzaldehyde and sodium phenolsulfonate are dissolved in deionized water, the pH value of the system is adjusted with a sodium bicarbonate solution, and finally copolymerization is carried out under the catalytic action of horseradish peroxidase (HRP) to obtain the formaldehyde-free leather synthetic tanning agent. Through ester producing reaction and combined polymerization, aldehyde group, carboxyl and phenolic hydroxyl which have tanning effect on leather collagen fibers and polyethylene glycol branched chains, sulfo group and the like which have the functions of penetration, lubrication and filling are introduced into the product structure, and the obtained product has moderate relative molecular weight, good permeability and high absorption rate, and is a pollution-free polymer tanning agent with green performance.

The invention discloses a preparation method of a green and environmental protection tanning agent, comprising the following steps: weighing starch, deionized water, sodium hydrogen sulfite, CMC, SDS, silicone oil, op-10, sulfur alcohol and NaOH solution, adding the starch, the deionized water A, sodium hydrogen sulfite, CMC, SDS, the silicone oil, op-10, sulfur alcohol and the NaOH solution to a flask, heating to 50-60 DEG C while stirring, then adding hydrogen peroxide A, heating to 94-98 DEG C after constant temperature stirring for reaction, then cooling to 75-85 DEG C, adding HCL and then dropwise adding an initiator and a monomer, and cooling to room temperature after constant temperature stirring for reaction, thus obtaining the green and environmental protection tanning agent. The green and environmental protection tanning agent prepared according to the method disclosed by the invention can effectively improve the water resistance and shrinking temperature of leather, and de-tanning is not easy to cause.

The invention provides a leather manufacturing method achieving three-waste discharge reduction. The leather manufacturing method can comprehensively achieve reduction of three-waste discharge in the leather manufacturing process. Through wastewater reuse, solids are inhibited from decomposing or dissolving and are recycled; and exhaust emission is reduced through reduction of volatilization of wastewater, the solids and chemical materials. The leather manufacturing method is specially characterized in that soaking, liming, reliming, lime removal and softening, pickling chrome tannage, degreasing, retanning, neutralizing and dyeing are conducted independently, water is saved by over 70%, and energy is saved by over 20%; emission of solid waste is reduced by over 70%; the chemical materials are saved by 15% to 100%, and pollution to air due to volatilization of the chemical materials is reduced; and by the adoption of the method, the quality of leather can be improved remarkably.

The invention relates to a method for tanning pigskin first layer shoe lining leather by utilizing a non-chromium metal compound tanning agent. The method comprises an oil adding step and a tanning step. In the tanning step, an LTA-100 metal (without chromium) compound tanning agent, non-chromium tanning chaperones D6, an auxiliary tanning agent GM-40 and the like are adopted. The method is characterized in that the leather shrinkage temperature in industrial production can reach more than 90 DEG C, which conforms to the shoe-making manufacture requirement; the hexavalent chromium and total chromium detection requirement of the environment identification product can be met; the method has no phosphorus pollution and no formaldehyde release; the tannery sludge can be directly burned; a post-tanning process and the material do not need special adjustment, and the integrity property is good when compared with the traditional leather-making process. The invention meets the limit requirement on the hexavalent chromium and total chromium content of the environment identification product, has high shrinkage temperature, and provides a new path for shoe-making enterprises to produce high-grade environment-protection shoe lining leather.