RU2027771C1 - Method of fur hide treatment - Google Patents

Abstract

FIELD: leather industry. SUBSTANCE: fur hides were washed with water at 25-35 C for 0.5-1.5 h, soaked off-defatted in lipase or acid or neutral protease solution at their consumption 0.1-2 and 0.1-1 wt.-% of hide mass, at 30-37 C, pH 3-7 for 1-6 h. Then softening is carried out in solution of enzymic preparation or composition of enzymic preparations with prevailing glycosidase activity at consumption 0.1-5 wt.-% of hide mass, at 30-37 C, pH 3-7 for 1-6 h. EFFECT: improved method of treatment. 3 tbl

Description

 The invention relates to light industry and can be used in the processing of raw materials of fur production: fur and fur sheepskin, skins of nutria, muskrat, rabbit, mink and others.

 A known method of processing fur and fur sheepskins using the enzyme preparation protosubtilin GZx (G10x) in the presence of formaldehyde, nonionic and anionic surfactants in an alkaline environment during soaking-degreasing [1].

 The disadvantage of this method is that the treatment of the skins is carried out under adverse conditions for the hair - in an alkaline environment, in this regard, formaldehyde is introduced into the processing solution, which negatively affects working conditions and the environment. In addition, this method is not applicable for the treatment of fur skins with a high fat content, as it does not provide sufficient degreasing of the skins. It was experimentally established that the use of this method in the treatment of muskrat and rabbit skins leads to a weakening of the connection between the hair and the skin tissue.

 There is a method of soaking rabbit fur skins using enzyme preparations of amylosubtilin GZx and maltavamorin G10x at a ratio of 2: 1, a concentration of 0.1-0.2 g / l and a processing time of 16 hours [2].

 It was experimentally established that this method is ineffective for treating fur and fur sheepskins, as well as skins containing a lot of fatty inclusions (skins of nutria, muskrat, mink, etc.), since it does not provide the necessary degree of degreasing and separation of the structural elements of the skin tissue , which negatively affects the quality of the finished product.

 There is also a method of processing fur raw materials using enzyme preparations of lipase and polygalacturonase in the processes of soaking and pickling [3].

 The disadvantage of this method is that the degreasing of the skins is carried out in an alkaline environment under adverse conditions for the hair. The use of formaldehyde in this process to prevent hair flowing negatively affects working conditions and the environment. The Novosti paste and sodium fluorosilicate (ammonium) have a negative effect on working conditions and the environment, which is introduced to prevent the development of microorganisms in the processing fluid that contribute to the fluidity of the hair and have a destructive effect on the skin tissue of the skin due to prolonged treatment (11- 13 h).

 The closest in technical essence and the achieved result is a method of processing fur raw materials, including washing the skins with water, soaking, degreasing in the presence of lipase and protease and tanning [4].

 The disadvantage of this method is its unsuitability for processing skins of nutria and mink, insufficient strength and elastoplastic properties of the semi-finished fur product.

 The aim of the invention is to expand the technological capabilities of the method, improving the quality of finished skins by improving the strength and elastoplastic properties, increasing the yield of finished products by area.

This goal is achieved by the fact that in the method of processing fur hides, including washing the hides with water, soaking and degreasing in the presence of lipase and protease and tanning, they additionally soften the solution of the enzyme preparation or the composition of enzyme preparations with a predominant glycosidase ability at a rate of 0.1 -5 wt.% Raw materials, a temperature of 30-37 ^o C, pH 3-7 for 1-6 hours, washing the skins with water is carried out at a temperature of 25-35 ^o C for 0.5-1.5 hours, when soaking degreasing protease use acidic or neutral and pro odyat this process at a rate of lipase and protease, respectively, equal to 0.1-2.0 and 0.1-1.0 wt.% skins temperature 30-37 ^o C for 1-6 hours.

 In the table. 1 shows a comparative analysis of the essential features of the preparatory processes for the known and proposed methods.

 Tanning and all subsequent processes and operations are carried out according to a known scheme.

 As a lipase, lipases of microbiological origin can be used, isolated, for example, from strains of Aspergillus oryzae, Rhizopus oryzae, Rhizopus arrhizus and others with lipolytic activity of 1000 units / g or higher, determined by the Ota-Yamada method.

 As a protease, acidic and neutral proteases of microbiological origin can be used, isolated, for example, from strains of Bacillus subtilis, Bacillus mesentericus, Bacillus licheniformis, Aspergillus oryzaе and others with proteolytic activity of 5-10 u / g or higher, determined by the modified Anson method .

 As an enzyme preparation or a composition of enzyme preparations with a predominant glycosidase ability, enzyme preparations or their compositions isolated, for example, from strains of Aspergillus awamori, Aspergillus oryzae, Aspergillus foetidus, Aspergillus niger, Bacillus subtilis and others having one or a complex of activities can be used for example, glucamylase, maltase, pectinase, exopoligalacturonase, hyaluronidase, amylase, etc.

It is known that the use of proteases in the treatment of fur skins helps to weaken the connection of hair with skin tissue. However, compliance with the soaking-degreasing regime of the claimed method (pH 3-7, temperature 30-37 ^o C, lipase consumption 0.1-2 wt.%, Protease consumption 0.1-1 wt.% Raw materials, sequential introduction of lipase and protease into processing fluid, etc.) allows you to get a semi-finished product with a strong connection of hair with leather tissue.

 The introduction into the technological cycle of the process of softening using an enzyme preparation or a composition of enzyme preparations with glycosidase ability ensures the necessary degree of separation of the structural elements of the skin tissue, as a result of which its elastic-plastic properties are improved, and the yield of finished products over the area is increased.

 An exception from the technological cycle of the pickling process is necessary, since it has been experimentally established that in the proposed method, pickling leads to a deterioration in the strength properties of leather tissue, a decrease in its heat resistance.

 Variants of the consumption of enzyme preparations and process parameters of the proposed method are given in table.2.

 The method according to examples 1-3 is as follows.

The fur sheepskin is washed with water for 0.5-1.5 hours at a temperature of 25-35 ^o C and subjected to soaking-degreasing in the presence of liporizin G10X lipase (lipolytic activity of 10,000 units / g) at a flow rate of 0.1-2 wt.% Skins at a temperature of 30-37 ^o C for 0.5 h, then a neutral protease protosubtilin G10X (proteolytic activity of 40 units / g) is additionally introduced into the treatment solution at a flow rate of 0.1-1 wt.% skins. The total duration of the process is 1-6 hours. Then, a multi-enzyme composition including enzyme preparations pectofoetidin G10x and celloviridine (glucoamylase activity, respectively, 102 units / g and 65 units / g, respectively) is carried out with a mutual ratio of 1: 1, when its flow rate of 0.1-5 wt. % of raw materials, temperature 30-37 ^o C, pH 3-7 for 1-6 hours. Then, tanning and subsequent processes and operations are carried out according to known technology.

 The performance of the semi-finished fur product obtained according to examples 1-3, according to a comparative example (according to the prototype) and according to GOST 4661-76 are given in table 3.

 As follows from table 3, the proposed method allows to obtain a high-quality fur semi-finished product with a stronger bond of the hair with the skin tissue, better strength and elastoplastic properties, less stiffness of the skin tissue and a larger yield over the area.

Claims (5)

 1. METHOD FOR PROCESSING FUR SKINS, including washing the skins with water, soaking and degreasing in the presence of lipase and protease and tanning, characterized in that, in order to expand the technological capabilities of the method, improve the quality of the finished skins by improving the strength and elastoplastic properties, increasing the yield of finished products by area, before tanning, an additional softening is carried out in a solution of an enzyme preparation or composition of enzyme preparations with a predominant glycosidase ability, and when soaked, it is degreased and a protease using acidic or neutral. 2. The method according to claim 1, characterized in that the washing of the skins with water is carried out at 25 - 35 ^o C for 0.5 to 1.5 hours 3. The method according to claim 1, characterized in that the soaking-degreasing is carried out at a flow rate of lipase and protease, respectively, equal to 0.1 - 2.0% and 0.1 - 1.0% by weight of the skins, temperature 30 - 37 ^o C for 1 to 6 hours 4. The method according to claim 1, characterized in that the softening is carried out at a flow rate of the enzyme preparation or the composition of the enzyme preparations 0.1 to 5% by weight of the skins, a temperature of 30 - 37 ^o C, pH 3 - 7 for 1 to 6 hours  5. The method according to claims 1 and 3, characterized in that when soaking, degreasing, the skins are initially treated in a lipase solution, followed by the addition of a protease.

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