SU133159A1 - The method of making yuft leather chrome tanning for shoes hot curing - Google Patents

Description

The currently existing technology for the production of Russian leather suitable for making shoes using hot curing does not provide the necessary water resistance of shoes made by this method. By using (for these purposes) usually a highly greased yuft, a sufficient strength of gluing the top to the rubber bottom of the shoe is not achieved.

The described method of making yuft leather of chrome tanning, unlike the well-known one, significantly improves the water resistance of shoes made by hot vulcanization and provides the necessary strength for gluing the top of the shoe to the rubber bottom. This is achieved by the fact that the Yuft skin, produced by known methods, with the usual content of fat, is additionally treated with various hydrophobic products that have high adhesive properties when combined with a rubber bottom, when sewing shoes using hot vulcanization.

According to the proposed method, the leather raw material after the processes of washing, washing and mezzanine goes to the washing with a content of sodium sulfite of 2.5-5.0 g / l.

Golding is carried out in two ways. In the first embodiment, this process is carried out in frame drums or vats at Zh. K. 3 - 3.5 sodium sulfide concentration of 0.8-0.9 g / l and lime - 10-12 g / l. The duration of ash is 36-40 hours. The temperature of the solution during the whole process is maintained at a level of 30-32. After 2, 4, and 18 hours from the beginning of the ashing period, the ash pits reinforce No. 133159-2 with sodium sulphide to the initial concentration. In the second embodiment, the ashing process is carried out for 3-4 days. The concentration of sodium sulfide is 0.6-0.8 g / l and lime 10-12 g / l. Solution temperature 18-22 °.

Doubling the die on a sawing machine is made on the basis of obtaining a finished skin thickness of at least 2.5 mm at the standard point.

Predtubilny and tanning processes, as well as washing, neutralization and dyeing operations are carried out in suspended drums according to well-known methods of producing chrome leather goods from cattle raw materials.

After the process of dyeing and washing, the semi-finished product goes to emulsion greasing, combined with kerosene treatment.

The process is carried out in a bath at a fluid ratio of 1-1.5 and a temperature of 60-65 °. The total fat consumption per pure fat is 9-10%, and kerosene is from the sliced weight. The preparation of the fat emulsion is carried out in the usual way, used in the fattening of chrome leather for the upper of the shoe with the use of synthetic fats in the bouquet.

On a fresh bath after fattening, the semi-finished product is doubled with vegetable or synthetic tanning agents. The consumption of tannins is 2-5% of the planed weight of the semi-finished product. The processing time is 1 hour with a liquid ratio of 1.0-1.5. After tannins, the skin is washed in running water for 10-15 minutes.

The impregnation of chromium leather to make it water resistant is carried out in one of the following ways:

Ivariant. Chromolan treatment.

A dilute solution of chromolane with a temperature of 40-45 ° is poured into the drum. The consumption of chromolane is 10% of the planed weight of leather, considering the technical product. The processing time is 1.0-1.5 hours, J.-K. - 0.6-0.8.

II variantImpression with SKS-30-1 or SKS-50-1ZhK latex - 0.8. The temperature of the poured water is 40-45 °. Latex consumption 20-30% of the planed weight of leather, counting on 20 / o-ny latex dry residue. Processing time - up to 3 hours. The pH of the bath is not adjusted.

1P option.

Impregnation with latex SKS-30-1 or SKS-50-1 with the subsequent treatment with chromolan.

Impregnation with latex is carried out according to the regime described in variant P. After the latex is fully processed, rinsing is performed on running water with a temperature of 35-40 ° for 10-15 minutes. Then, the spent wash liquid is completely drained.

Chromolan treatment is carried out according to the mode given in option I at the rate of the technical product consumption of 7.5-10% of the weight of planed leather.