RU1801985C - Method of leather manufacture from swine raw - Google Patents

Abstract

SUMMARY OF THE INVENTION: The tanned semi-finished product is finished up with tanning chromium compounds, treated with a mixture of phenolic synthetic tanning agents and tanning chromium compounds at a flow rate of 2–3%, respectively, for tanning agents, and 0.35–0.5%, counting for oxide chromium, by weight of the semi-finished product at a pH of 4.0-4.2. Then, neutralization is carried out at a pH of 6.2-7.0.3.

Description

The invention relates to the leather industry and can be used to make leather from pork raw materials.

The aim of the invention is to increase the elasticity, softness and grading of the finished skin.

The method is as follows ...

Semi-finished products tanned according to the standard method are sorted, planed to the required thickness, and completed in a batch of leather from raw materials without significant defects.

Degreasing and retanning is carried out according to a standard procedure.

At the end of the chrome retanning, the pH is adjusted to 4.0–4.2. At a pH below 4.0, tanning agent stains and above 4.2 a precipitate of chromium hydroxide precipitates. To a bath with a pH of 4.0-4.2 serves a solution of organic tanning agent in an amount of 2.0-3% of

the weight of the semi-finished product based on tanning, tanning chromium compounds based on chromium oxide in an amount of 0.35-0.5% and electrolyte-resistant fat in an amount of 2-4% by weight of planed leathers, and also sodium carbonate or bicarbonate for maintaining a pH in the range of 4.0-4.2, the amount of which is selected experimentally, based on the acidity of the tanning agents.

Fat is added to soften the skin, as It is known that pre-fatliquoring allows you to obtain soft skin with less fat consumption than with single-phase fatliquoring.

The drum is rotated, after 60 minutes the bath is drained, washing is performed. Then through neutralization is carried out to a pH of 6.2-7.0, T 30-35 ° C. After 90 minutes of rotation, a control is carried out: pH 6.2-7.0;

about y

00

ate

methyl red should be yellow throughout the cross section. In the case of a low pH or red coloring of the middle layer of skin, sodium carbonate is added to achieve these parameters. Exceeding the pH above 7.0 leads to partial skin hollowing, stiffness and cracking of the face layer, below 6.2. - the skin is not soft enough. Then draining, washing with water T 60 ° C, dyeing according to a standard method. The fatliquoring is carried out with a fat emulsion with a consumption of 8-12% of pure fat by weight of the semifinished product for shoe leathers H..J2-15% for clothes. After working off with a fat emulsion (within 40-70 minutes), the bath is brought to T45-50 ° C by full or partial draining and a set of cold water. An organic tanning agent is retanning the cooled bath: a mixture of vegetable tanides and synthetic tanning agents for shoe and purely synthetic tanning leathers. After 60 minutes organic acid is fed to the waste bath to a pH of 3.5-4.0 to fix fats, tanning agents, dyes. Then flushing and discharge are carried out.

Drying and moisturizing processes and finishing operations are carried out according to a standard method, according to options including a breakdown in the drum.

Example 1. The drum was loaded p / f with an area of 80-120 dm2, a thickness of 0.8-0.9 mm, degreased, retaned by a standard method. Then, with a 10% sodium carbonate solution (GOST 1.0689-75), the pH of the spent chrome retanning bath was adjusted to 4.0. A tanning solution No. 2 (TU 38-10271-78), a dry chrome tanning agent with a basicity of 40% (TU 6-18-23-87), and VNIIZH paste (TU-6-04-53-82) were applied to a bath with pH 4.0 ) in an amount of 3% by weight of planed leathers and a 10% sodium carbonate solution in an amount of 30% by weight of chromium oxide. The drum was rotated for 60 minutes, draining, washing. Then through neutralization was carried out to a pH of 6.2-7.0 at T 32 ° C and g. 1.5 sodium carbonate in an amount of 1.8% and ammonium sulfate (GOST 9097-82) in an amount of 2.0% by weight of planed leathers. After 90 minutes the rotations were monitored by the Metolov red indicator - the skin section was yellow over the entire cross section, pH 6.2. Next, we drained, washed and dyed according to the standard procedure. Subsequent fatliquoring was carried out with a fat emulsion of the following composition: (wt.% Per technical product)

Synthetic fat

(TU 38-1016.92-79). 4,5

Sulfonated

 fish oil (TU 6-01-868-79) 4,5 Paste VNIIZH

(TU 6-04-53-82) - 4.0 Parachlor250. 1,5. Emulsifier 0.7

The drum was rotated for 60 minutes. The bath was cooled to T 45 ° C by partial draining and a set of cold water, Then a dispersant NF grade A 55% (GOST 6848-79) was supplied in an amount of 2%, and tanning agent No. 2, in an amount of 1.5% for tanning agents and willow extract (OST 17-121-71) - 1.5% for tandy of the weight of planed leathers, The drum was rotated for 60 minutes, formic acid was applied (GOST 1706-78) 20%, calculated as 0.7% of the active substance by weight p / f, rotated 30 minutes

Further processes were carried out according to a standard technique,

In this example, you can get elastic skin for. upper shoes.

Clothing skin is obtained according to example 2.

Example r 2. The drum was loaded p / f

an area of 80-120 dm2, thicknesses. 0.6-0.7 mm. Before

all processes were following the example

No. 1 at railway station 2.

The fatliquoring was carried out with the same fat emulsion as in Example 1, but with a consumption of 12-15% of pure fat by weight of planed leathers. The drum was rotated for 60 minutes, the bath was cooled to T 45 ° C by partial discharge and a set of cold water. Then, body no. 2 was fed in an amount of 3% for tanning leathers massed from the mass.

The remaining processes were carried out as in example 1.. : ..:

When processing the semi-finished product by examples, various amounts of tanning agent No. 23, dry chrome tanning agent, fat emulsion, dispersant NF, willow extract were taken, the pH of neutralization was changed. The results are summarized in table. 1,2,3.

Sample The tanned semi-finished product, similar to the semi-finished product according to examples 1 and 2, was processed according to the method for raw bovine cattle, taken as a prototype (4). .to. -. 1.5, the consumption of glutaraldehyde 1.5%, paste VNIIZH-3 from the mass of the semi-finished product for 60 minutes, drain, rinse. Then, neutralization was carried out at T - 35 ° C; 1.5, sodium carbonate 1.8%, ammonium sulfate 2.0% for 90 minutes, pH 6.3. the cut over the entire cross section during the test with the indicator methyl red yellow. Draining, washing, dyeing according to example 1, draining the bath, a set of water T - 40 ° C, Zh.K. - 1.5, chrome synthane retanning and tanning agent Nfe 2 in an amount of 3% for tanning by weight s / f and

0.5% tanning compounds of axis chromium, 40%, counting on chromium oxide, for 60 minutes, drain, set of water 40 ° С, f.k. d 15, retanning of 1.2% willow extract, 1.2% BNS tanning agent (all for tanning), 2% NF dispersant 55% for 60 min, draining, water set at 60 ° С, fatliquoring with fat emulsion ( composition and consumption according to example 1), further processes according to example 1.

Comparative physical and mechanical properties of the skins obtained by the presented examples are given in table 1.

The use of the present invention will improve the quality of shoe and clothing leather from pig raw materials by increasing elasticity and softness, and increase their grading by reducing the area of lesions with defects, local stiffness and breathability, as well as improve the cutting properties of the leather by improving the uniformity of elastic properties by area.

Claims (3)

SUMMARY OF THE INVENTION 1. Method for producing leather from pork raw materials, including washing the semi-finished product, retanning, neutralizing, dyeing, treating with a mixture of phenolic synthetic tanning and tanning compounds of chromium, fatliquoring with a fat emulsion, treating with an organic tanning agent and organic acid, using an alternative and th - so that, in order to increase the elasticity, softness and grade of the finished skin, retanning is carried out with a tanning chromium compound, treatment with a mixture of phenolic synthetic tanning agents and tanning chromium compounds is carried out before neutralization at their consumption, respectively equal to 2-3%, counting on tanning agents and 0.35-0.5%, counting on chromium oxide, based on the weight of the semi-finished product at pH 4.0-4.2, and neutralization is carried out at pH 6.2-7, 0. 2. The method according to claim 1, including the fact that, in order to obtain elastic leather for the upper of the shoe, the fatliquoring is carried out at a flow rate of the emulsifying emulsion of 9-12%, considering pure fat, and as organic tanning agents use a mixture of synthetic and vegetable tanning agents at a ratio of 1: 1 and a consumption of 2.5-3.5%, based on tanning agents, based on the weight of the semi-finished product. 3. The method according to claim 2, characterized in that, in order to obtain clothing skin, fatliquoring is carried out at a consumption of fatliquoring emulsion of 12-15%, counting as pure fat, and synthetic tanning agent is used as an organic tanning agent at a rate of 2.5-3.5%, counting on tanning, by weight of the semi-finished product. Table 1 Tabl 3