RU2062791C1 - Method of fur hide treatment - Google Patents

Abstract

FIELD: fur hide finishing. SUBSTANCE: fur hides were subjected for soaking off, fermentation and tanning. Fermentation is carried out in fermenting solution (cultural fluid from baker's yeast production) at pH = 4.5-5.0, proteolytic activity is 70-90 U/g casein. Temperature of fermenting solution is maintained from 20 to 45 C and hides were kept in this solution for 24-48 hr. EFFECT: improved method of treatment.

Description

 The invention relates to the technology of dressing fur skins.

 A known method of dressing fur skins (rabbit, nutria, etc.), including the following basic operations: soaking, in which the fur skins are immersed for several hours (12 or more) in a solution containing salt and an antiseptic; souring, which consists in treating fur skins that have been soaked in soaps, prepared in, for example, water, coarsely ground oat or barley flour, sodium chloride, and which have accumulated as a result of acidification of organic acids in an amount of at least 3-5 g / l and enzymes that have a loosening effect on the skin tissue to acquire the last “pull” property (the ability to easily deform in the longitudinal and transverse directions); and tanning, which consists in keeping fur skins in tanning solutions containing tanning agents of inorganic origin (chromium and aluminum compounds) or organic (formaldehyde, vegetable tannides, unsaturated fats), which increase the chemical, mechanical and hydrothermal stability of the skin tissue as a result of interaction with tissue proteins (1,2).

 The disadvantages of the known method for the production of fur skins include the difficulty of controlling one of the main operations of dressing fermentation, in which it is necessary to control both the indicators of the starting materials of the fermentation solution (flour diastatic ability, acidity, proteolytic activity) and strictly control the acid content in the fermentation solution. Deviations from optimal values can lead to under-peeling of the skins or weakening of the connection with the dermis, before the peaking is achieved. In addition, a significant drawback of this operation is its significant duration, as well as the need for food products.

A known method of producing fur and fur sheepskin, including the following basic operations: soaking, pre-nickel, softening, pickling, tanning. In this method, in order to achieve a fine disintegration of collagen bundles of skin tissue, usually carried out by pickling, which consists in treating fur raw materials with a pickle solution consisting of acid and sodium chloride, a softening operation is introduced, which consists in exposing the skin tissue to carbohydrates with enzymatic preparations, in particular, maltavamorin P2b (available as one stripped off extract). The softening is carried out at a temperature of 38 ^o C at a certain concentration of maltavamorin with the addition of sodium chloride and sodium silicofluoride in the emollient solution (the latter components prevent the accumulation of bacteria in the solution that weaken the activity of enzymes). The duration of treatment with emollient is 24 hours (2).

 This method allows to obtain plastic soft leather tissue in a less laborious way and without the use of food products (compared with the above method, including pickling). However, this method requires the presence of an enzymatic preparation, which is associated with additional costs for its acquisition; due to the additional softening operation, the duration of the dressing process increases. Processing skins with a picel solution also requires strict acid dosage and process control. The use of acid requires the observance of strict safety measures during maintenance, in addition, the aggressiveness of the batch solution affects the durability of the equipment.

 The proposed method for processing fur skins eliminates the above disadvantages of the known methods, significantly simplifies the process of skinning, namely: it does not require the preparation of strictly dosed working solutions, eliminates the risk of overpickling skins and, accordingly, reducing the wear of skins, reduces the duration of the skinning cycle. In addition, the proposed method of processing fur skins eliminates the use of food products, special enzyme preparations of factory production, acids, which significantly reduces the money and labor costs, there are no safety or environmental problems associated with the use of acids.

 The proposed method for processing fur skins involves soaking the skins in an aqueous solution containing sodium chloride and an antiseptic, fermenting water from yeast production, tanning in aqueous solutions of basic chromium salts or other tanning agents. The use of yeast plants for fermentation of a ready-made quasiline solution containing organic acids and groups of enzymes necessary for affecting the skin tissue allows skinning in the mild optimal conditions of the quasil solution on the skin tissue without the need for complex control of the working solution and process, without using food products, acids and special enzyme preparations, excluding other costs associated with the use of well-known picnels and kvasilnyh solutions.

 The proposed method of processing fur skins is as follows.

Fur raw materials to be made, for example, nutria, rabbit, muskrat, etc. skins, are soaked at the initial stage of processing by the window method, for which fur skins are immersed in a solution of sodium chloride with a concentration of 5-15% having a liquid coefficient (g.k.) 5 -10, and withstand skins in this solution from 24 to 48 hours at a temperature of 15-25 ^o C (room). Detergent can be added to the solution. In the process, preservatives, dirt, blood, soluble proteins are removed from the fur raw materials, and the proteins of the skin tissue interact with water, which is accompanied by hydration and swelling of the tissue and bringing the skins to a state as close as possible to the pair. The skins that have passed through the soak are washed in water having a temperature of 15-25 ^° C for 30-60 minutes, after which the skins are fermented. Fermentation is the treatment of skins with a kvassilnym solution, which is used as wastewater from yeast industries, containing the right amount of organic acids and two types of enzymes: proteolytic and amylases. The optimal temperature of the solution is 20-45 ^o C, the reaction of the medium is pH 4.5, the average duration of the treatment of the skins with the solution is up to 48 hours (the duration can vary for different types of animal skins). As the skins are found in a fermented solution, organic acids loosen the skin tissue, proteolytic enzymes, interacting with proteins, break down collagen bundles, amylases act on the carbohydrate components of the skin tissue, converting them into soluble forms. Due to the fact that the wastewater from the yeast industry contains a sufficient amount of mineral salts that impede “pressure”, the addition of sodium chloride (as is the case with known methods of pickling) is not required. As a result of pickling, leather fabric acquires plasticity, reduces weight, while maintaining mechanical strength and size. The duration of the pickling is determined by the "dryer" or a duster from the inguinal part of the skin. After the pickling operation, the skins are washed in water with the addition of washing powder and rinsed. Then the skins are coiled by any suitable method, while the subcutaneous fat layer is removed from the skins that have been pickled relatively easily. The tanning operation (i.e., fixing the fiber separation obtained by fermentation and making the skin resistant to heat, moisture, chemicals and enzymes) is carried out with a tanning solution based on chromium compounds (basic salts of trivalent chromium) or with dry chrome tanning agent (which is produced in the form basic chromic sulfate with a given basicity), while tanning substances penetrate vigorously and evenly into the thickness of well-loosened skin tissue as a result of souring. Allowed tanning and other famous tanning agents. After tanning carry out the fatliquoring of the skins by known methods.

 Dressing of experimental batches of fur skins of a rabbit, nutria, muskrat showed the receipt of mezra of good quality and confirmed the efficiency of the proposed method. The use of wastewater from yeast production as a ready-made kvassilny solution containing all the necessary components for exposure to skin tissue (and not containing harmful or toxic substances, because the yeast production of food and feed purposes are strictly regulated), can significantly simplify the process of dressing fur skins , reduce the cost of funds, labor and time for the manufacture of fur, as well as avoid environmental problems that occur when using chemical acids to obtain the same result ultat.

Information sources
1. Once again about the dressing of skins, an article in the journal "Homestead" N 26, 1985, p. 22-24.

 2. Yu.N. Aronina. Technology of dressing and dyeing of fur, a textbook for the average. prof. schools. M. Light and food industry, 1981, p. 47-50, 51.

 3. Chemistry and technology of leather and fur, a textbook for high schools. Ed. prof. I.P. Strakhova, M. Legkoprombytizdat, 1985, p. 89-91.

Claims (1)

A method of processing fur skins, including soaking, pickling skins in a fermentation solution and tanning, characterized in that the culture fluid used for production of baker's yeast with a pH of 4.5 5.0 and a proteolytic activity of 70 to 90 units / g casein is used as a fermentation solution. and fermentation is carried out at a temperature of the solution of 20 45 ^o C and aging the skins in the solution of 24 48 hours