RU2238980C1 - Method of pickle salting-tanning of genuine fur, preferably rabbit fur - Google Patents

Abstract

FIELD: fur industry.

SUBSTANCE: invention relates to technology of manufacture of fur semiproduct with soft and long hair. Crude fur is treated with composition containing oxalic acid, table salt, alum, nonionic surfactant, Coripol-pelzlicker, and water. Coripol-pelzlicker is added to composition 12-18 h before pickle salting-tanning is ended. Treatment is continued at 20-25^оС. Process is carried out for 24-26 h at liquid coefficient 20-22.

EFFECT: improved feasibility of process, reduced power consumption, and improved quality of semiproduct.

2 cl, 1 tbl, 6 ex

Description

The invention relates to a technology for the manufacture of semi-finished fur products with soft and long hair and can be used in the fur industry, in particular for the manufacture of rabbit skins.

The well-known industrial technology of pickling-tanning of a fur semi-finished product with a soft long hair coat in longboats at 40-50 ° С, liquid coefficient (LC) 9-25, pH 3.5-10 by treatment with a composition based on both mineral and organic acids, chromic extract, sodium chloride and excipients. The quality of the semi-finished product produced by this technology meets the requirements of GOST [RF Author Certificate No. 755843, publ. 08/15/1980].

The presence of a long hairline, prone to scaling, requires liquid operations at high LC, and fur production by this technology is accompanied by the formation of a large amount of wastewater containing toxic chromium oxide compounds (VI).

A known method of processing fur, eliminating the use of chromium compounds by treatment with an aqueous composition based on aluminum alum, fat emulsion, chloride, carbonate, sodium thiosulfate. Aluminum alum is pretreated with sodium carbonate, after which an additional 40% formalin solution is added [Patent on Application No. 93019576/12, claims, publ. 10/09/1995].

The method allows to obtain a plastic semi-finished product (full elongation by 6%), reduce weight by 13%, but a significant drawback of this method is the use of formalin - a substance that is toxic and harmful to humans.

A known method of pickling-tanning of natural fur by processing raw materials at 40-50 ° C with a composition containing sulfuric or acetic acid, sodium chloride, chromic extract, hyposulfite, soda ash and auxiliary substance OP-10, the processing time of the fur is 9-12 hours, LCD 9 -11 [Aronina Yu.N. et al. Fur technology. M., 1974]. The quality of the fur produced by this technology meets the requirements of GOST.

However, this method does not exclude the formation of a large amount of wastewater containing chromium, and is also carried out at elevated temperatures, which leads to high energy costs.

The closest to the claimed technical solution according to the technical essence and the achieved effect is a method of pickling-tanning of natural fur by processing raw materials at 30-35 ° C with a composition containing sulfuric acid, sodium chloride, chromic extract, aluminum alum, excipients: hyposulfite, soda ash, urotropin; the processing time of the fur is 10-12 hours, LCD 8-10 (Klyagina NI, Martynova SF. Handbook of the fur and sheepskin-fur coat industry. M., 1959, pp. 156-157).

The disadvantage of this method is the use of toxic substances-urotropine, as well as a large amount of wastewater containing chromium. In addition, due to the presence of chromium compounds, this method does not allow to obtain a sufficiently light, soft and plastic fur semi-finished product, which would meet the requirements of modern trends in the fur fashion. Since processing is carried out at elevated temperatures, additional energy consumption is required.

The technology of chrome-free tanning is known, however, it requires the use of formaldehyde, a substance toxic and harmful to humans (RU 93019576/12, from 10.09.1995).

It is known to use oxalic acid in the process of bleaching the hair at the recovery stage to maintain a favorable pH of the process (Klyagina NI, Martynova SF, Handbook of the fur and sheepskin coat industry. M., 1959, p. 174).

The technical result of the invention is to improve manufacturability, to obtain a soft, plastic and light semi-finished product while maintaining its strength by eliminating the use of chromium compounds, reducing energy consumption.

This technical result is achieved by the fact that in the method of pickling-tanning of natural fur, mainly rabbit, which consists in processing the raw material with a composition containing acid, aluminum alum, excipients, including sodium chloride, oxalic acid is used as the acid, and as auxiliary substances additionally use a nonionic surfactant and a fatliquoring material - Coripol-Peltzlicer in the following ratio of components in the processed with Stava, g / l:

Oxalic acid 16-22

Salt 20-30

Aluminum Alum 25-30

Nonionic surfactant

substance 1.5-2

Coripol-Peltzicker 1-2

Water rest,

moreover, Coripol-Peltzicker is administered 12-18 hours before the end of pickling-tanning, at a temperature of the process of pickling-tanning 20-25 ° C.

The pickling-tanning process is carried out at a liquid coefficient of 20-22, the duration of the process is 24-26 hours.

In the inventive method, oxalic acid is used as a masking agent, which when interacting with aluminum alum forms alumina-oxalate complexes that bind to collagen, while strengthening the structure of the skin tissue of the fur.

It is essential to use oxalic acid in combination with aluminum alum, sodium chloride, a nonionic surfactant, anionic fatliquoring agent - a combination of surface-active emulsifiers with hydrocarbons with an active substance content of 50% - Coripol-Peltzlicer in the stated ratio of ingredients.

Only the claimed combination of features allows to achieve the above objective of the invention.

Example 1. Water is added to a longboat at a temperature of 25 ° C and 30 g / l of sodium chloride, 16 g / l of oxalic acid, 30 g / l of aluminum alum are dissolved in it, 1.5 g / l of Pickenol is added. The solution is mixed, picking up a sample for analysis of salt and acid, and then load the rabbit skins. 16 hours after the start of pickling-tanning, an anionic fatliquoring agent is added - a combination of surface-active emulsifiers with hydrocarbons with an active substance content of 50% (Coripol-Peltzlicer) in an amount of 2 g / l. The total duration of the process is 24 hours, LCD 20. After unloading the skins are layered for 24 hours. Fur quality indicators are given in the table.

Example 2. The process of pickling-tanning is similar to example 1, only oxalic acid is added in an amount of 22 g / L.

Example 3. The process of pickling-tanning is similar to example 1, only oxalic acid is added in an amount of 20.9 g / L.

Example 4. Pour water at a temperature of 20 ° C into a longboat and dissolve 20 g of sodium chloride and 20.9 g / l of oxalic acid, 25 g / l of aluminum alum and 2 g / l of Peramit ML in it, mix the solution, wipe the sample for analysis on the content of salt and acid, and then load the rabbit skins. Fatliquoring is served in the bath after 12 hours in an amount of 1 g / l. The duration of the process is 26 hours, ZhK 22. After unloading - laying skins for 24 hours.

Example 5. The process of pickling-tanning is similar to example 4, only fatliquoring is served 16 hours after the start of the process.

Example 6. The process of pickling-tanning is similar to example 4, only fatliquoring is served 18 hours after the start of the process.

Analyzing this table, we can conclude that in the case of Example 3, the highest weld temperature is observed, and in the case of Example 5, the greatest elongation at break is observed, therefore, the parameters of these processes should be considered optimal. After the pickling-tanning process, the skins have not yet passed all the processing stages, and insufficient welding temperature can be increased by subsequent retanning, and acidity is eliminated by subsequent neutralization, as a result of which fur skins comply with the requirements of GOST 2974-75 dressed rabbit skins.

Indicators of abrasion of the hairline and elongation at break by GOST are not required, but in this case they are necessary to represent the strength of the hairline and the elasticity of the skin tissue of the fur, since the wear resistance of the fur product depends on the strength of the hair, and high elasticity is subsequently required when cutting skins and the manufacture of fur products.

The proposed method, in comparison with the known method, completely eliminates the use of chromium compounds, which is an important environmental aspect, in addition, the absence of chromium allows further finishing operations using hydrogen peroxide, in particular bleaching. Also, this method allows you to get a semi-finished fur product with a fairly strong structure of the dermis and at the same time soft, light and plastic. Since the process is carried out at room temperature, energy is significantly saved. It should also be noted the cheapness of the chemical materials used.

Claims (2)

1. The method of pickling-tanning of natural fur, mainly rabbit, which consists in processing raw materials with a composition containing acid, aluminum alum, excipients, including sodium chloride, characterized in that oxalic acid is used as an acid, and nonionic superficially is used as excipients -active substance and fatliquoring material - Coripol-Peltzlicer in the following ratio in the treated composition, g / l: Oxalic acid 16-22 Salt 20-30 Aluminum Alum 25-30 Nonionic surfactant 1.5-2 Coripol-Peltzicker 1-2 Water Else moreover, Coripol-Peltzicker is introduced 12-18 hours before the end of pickling-tanning, at a temperature of the process of pickling-tanning 20-25 ° C. 2. The method according to claim 1, characterized in that the pickling-tanning process is carried out at a liquid coefficient of 20-22, the duration of the process is 24-26 hours