SU1214764A1 - Method of manufacturing leather - Google Patents

Description

The invention relates to leather industry and can be used for tanning in the production of heat-resistant yuft leathers.

The aim of the invention is to intensify and simplify the process by eliminating the milling process.

According to the proposed method of producing leather, the process of softening is eliminated, and desalting and salting are carried out jointly at a consumption of ammonium sulphate of 10-12% by weight of a mole. At the same time, I conduct tanning in the presence of sodium acetate in the amount of 1.0-1.2% by weight of a mole at a pH of 3.3-3.8.

It is known that concentrated ammonium sulfate solutions have a strong salting out and drying effect, which is due to the significant hydration of ion 30, the maximum amount per SO4 ion is 40 molecules, and Cf ion is 4.8.

As a result, the penetration of chromium, titanium and zirconium particles into the dermis is accelerated. The use of a significant amount of ammonium sulfate before tanning with zirconium compounds slows down the binding of tanning complexes of zirconium in the initial stage of tanning, which eliminates the appearance of tightening on the front surface of the skin. The use of a large amount of ammonium sulfate greatly accelerates the desalination process and prevents the formation of gypsum on the surface of the skin as a result of the formation of the (NH) 2Ca (.50) 2 5 double salt that has good solubility.

The specified amount of s-sulfonate sulphate does not result in thin skin, since after salting, the semifinished product undergoes tanning with chromium, titanium and dirconi 5 compounds, retanning with syntans and treatment with resins, resulting in a filled heat-resistant yuft,

As a masking agent

sodium acetate is used. It is added to mask the heteropoly junction (mixed) complex compounds formed with the participation of chromium and titanium complexes.

and zirconia. Mixed complex tanning agents are more resistant to dilution and higher pH than individual light zirconium compounds.

Since according to the proposed method, tanning is carried out with simultaneous dosing of chromium, titanium, zirconium and acetate compounds.

sodium, then in solution both sequentially and simultaneously the formation of mixed tannins and their masking.

As a result, the danger of hydrolysis of titanium and zirconium compounds does not arise and the possibility of metal hydroxides is excluded.

Consumption of zirconium compounds and

titanium is, respectively, 0.2-0.4 and 0.5-0.7% by weight of mole, in terms of oxides, which reduces the consumption of chromium compounds to obtain a heat-resistant

yufti from 2.0% to 1.4-1.6% by weight of mole in terms of chromium oxide.

By tanning with masked mixed complexes, the required thermal stability is achieved at

reduced consumption of chrome tanning agents while simultaneously giving fullness to zirconium and titanium compounds.

The proposed method is carried out

next item.

Example 1. A mollusk of light bygus after ash and skulking is washed, treated in a drum with a solution of ammonium sulfate at a temperature of 20-25 C, LC 1.0-1.2 for 45-60 minutes. The consumption of ammonium sulfate 12% by weight mole. After the salt process, sulfuric acid is simultaneously poured in an amount of 0., 3% uh are covered with sodium acetate, sodium sulfate zirconate, ammonium sulfate titanylate, and a chromium extract. Total tanning time 8-10 hours. Consumption of sodium acetate

1.2% ammonium sulfate ammonium 0, 7% in terms of titanium dioxide, sodium sulfate zirconate 0.4% in terms of zirconium dioxide, chromic extract 1.6% by weight

mole, pH of the tanning solution 3.2–3.4 ° After 4-6 hours from the onset of tanning, urotropin is added in an amount of .1%. After neutralizing the subdub.

It is syntanami at a rate of 5% by weight of the mole. All further processes and operations are carried out according to the standard procedure for the production of heat-resistant Yuft skin.

Approximately 2. The middle cruisers after ash and skimming are washed, drummed with a solution of ammonium sulfate at a temperature of 20-25 s, LC 1.0-1.2 for 45-60 minutes. The consumption of ammonium sulfate 11% by weight mole. After the salting process, sulfuric acid in an amount of 0.3% is simultaneously poured in, sodium acetate, sodium zirconate, ammonium sulfate and ammonium sulfate and chromium extract are poured. The total duration of tanning is 8-10 hours. Consumption of sodium acetate 1.1%, ammonium titanylate sulfate 0.6% based on titanium dioxide, sodium sulfate 0.3% based on zirconia, chromic extract 1.5% by weight mole , the pH of the oak solution 3.2-3.4. After 4-6 hours from the onset of tanning, urotropine is added in an amount of 1%. After neutralization, they are duplicated with syntans at a rate of 4% by weight of the mole. All further processes and operations are carried out according to the typical method for the production of heat-resistant Russian leather.

PRI me R 3. The pads are easily washed and treated with an ammonium sulphate solution at a temperature of 20–25 ° C, LC 1.0–1.2 for 45–60 minutes after ash and skins are washed in a drum. The consumption of ammonium sulfate 10% by weight mole. After the salting process, sulfuric acid in an amount of 0.3% is simultaneously poured in, sodium acetate, ammonium sulfate ammonium, sodium sulfate zirconate and chromium extract are poured. The total duration of tanning is 8-10 hours. Consumption of sodium acetate 1%, ammonium sulfate ammonium 0.5% based on titanium dioxide, sodium sulfate 0.2 0.2 based on zirconium dioxide, 1.4% by weight chromium extract, pH of tanning a solution of 3.2-3.4. After 4-6 hours from the onset of tanning, urotropine is added in an amount of 1%. After neutralization, subtitle with syntans at a rate of 3% by weight of the mole. All further processes and operations are carried out according to the standard procedure for the production of heat-resistant Yuft skin.

4764

In tab. 1 is given a comparative description of the quality of leather, developed by the proposed method and the prototype. 5 In table. 2 gives a comparative description of leather, developed by the proposed method and provided OST 17-317-74.

Table 1

The chemical composition of the physico-mechanical properties of the skin. And the total duration of the treatment

The method of tanning in the laboratory

proposed

prototype

Moisture contents,%

Strength at stretching 10 Sha

14 14

2.51 2.10

Stress at occurrence of cracks on the face layer 10 MPa

Elongation at a voltage of 10 MPa,%

2.49 1.8

27 27

Temperature is about

Svarivany, With

Total duration image10 101

Mass fraction,% of moisture, not more than

Continuation of table 2

3.8

0, 9

1.0

) 8.4

4, 3

25.1

7.5-11.5

17.5

Compiled by S. Likhachev Editor L. Povhan Tehred 3.Paly Proofreader E. Sirohman

Order 858/39 Circulation 379Subscription

VNIIPI USSR State Committee

for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5

Branch ShSh Patent, Uzhgorod, st. Project, 4

Continued table. 2

layer (by skin), MPa, not less

Permeability

(by batch),

ml (cm), not more than

Dynamic permeability (by batch), min

24.9

0.3

35

16.5

0.4

thirty

Vapor permeability for moisture evaporated from the free surface (by batch),%, not less

28

25

Temperature of welding, С, not

less

108

104

Claims (2)

1. METHOD FOR PRODUCING LEATHER, mainly heat-resistant yuft, including unwinding of raw materials, gritting, fouling, washing, anesthetizing of the foil with ammonium sulfate, salting and tanning with chromium, titanium and zirconium compounds, characterized in that, in order to intensify and simplify the method by eliminating the process softening, desalting and salting are carried out jointly at a flow rate of ammonium sulfate 10-12% by weight of the target. 2. The method according to π. 1, which is related to the fact that, in order to improve the quality of leathers, tanning is carried out in the presence of sodium acetate in an amount of 1.0-1.2% of the weight of a loach at a pH of 3.3-3.8.