RU2437940C1 - Method of pelt processing - Google Patents

Abstract

FIELD: process engineering. ^ SUBSTANCE: proposed method comprises retanning half stuff by chrome tanning agent, neutralisation, rinsing, dyeing, stuffing, filling with water-soluble acrylic retanning by organic tanning agents, setting, drying and pickling by applying clear primer, first compaction, twofold application of finishing composition, first fixation of coating, second compaction and second fixation. Filling with acrylic polymer is performed after dyeing. retanning by organic tanning agents is performed prior to stuffing. After stuffing, half stuff is additionally filled for 20-30 min with 40%-water dispersion of copolymer of butadiene, acrylonitrile and methacrylic acid in the ratio of 50:45:5 at the flow rate of 3-4% of half stuff bulk. ^ EFFECT: production of water-, oil-, gasoline- and heat resistance leather. ^ 2 cl, 2 tbl, 5 ex

Description

The invention relates to methods for the production of special types of leathers and can be used in the production of water-, oil-, benz-, heat-resistant leathers for various purposes and assortment.

A known method of producing leather, including the retanning of the semi-finished product with a chrome tanning agent, neutralization, dyeing, fatliquoring, retanning with organic tanning agents, wiring, drying and finishing by applying unpigmented soil and a coating composition. The method allows to increase the water resistance of the skin, the resistance of the coating to wet friction and its adhesion to the skin due to the introduction of a copolymer of α, α ^' -dihydroperfluoroheptyl acrylate with N-methylol methacrylamide of the LF-M grade (SU 1420022 A1, class C14C 11 into the impregnating soil and topcoat) / 00, 08/30/1988).

The disadvantage of this method is the relatively low water, oil, gas resistance of the finished leather and the resistance of the coating to wet friction.

There is also known a method of producing leathers, including retanning a semi-finished product with a chrome tanning agent, neutralizing, dyeing, fatliquoring in the presence of hexamethylenetetramine in an amount of 8-10% by weight of fat, sequential treatment with sodium formate, chrome tanning agent and potassium alum at a flow rate of 0.3-0, 5, 0.3-0.5%, based on chromium oxide, and 1.8-2.0% by weight of the semi-finished product, retanning with an organic tanning agent, wiring, drying and finishing by applying pigmented soil, a coating composition and fixing nitroemulsion varnish. At the same time, hydrogen peroxide is additionally added to the compositions of pigmented soil and topcoat 10-30% by weight of the pigment concentrate, and GKZh-94 silicone fluid in the amount of 3-5% by weight of the varnish is introduced into the fixing varnish. The method allows to increase the water-, oil-, heat resistance of leathers from cattle skins (SU 1583445 A1, class C14C 9/00, 11/00, 08/07/1990).

The disadvantage of this method is the low gas resistance obtained with its help leather for the top of working and sports shoes.

The closest analogue of the proposed technical solution is a method for producing leathers, including retanning of the semi-finished product with a chrome tanning agent, neutralization, washing, dyeing, washing, fatliquoring, filling with MBM-3 brand acrylic copolymer in an amount of 3-4% by weight of the semi-finished product, retanning with organic tanning agents, washing ( after filling, retanning or after fatliquoring), wiring, drying and finishing by applying unpigmented soil, first pressing, two-time coating composition, first fixing the coating of the second pressing and fixing the second cover. When finishing leathers, a composition containing 20% acrylic emulsion A — 10 wt.%, 20% dispersion MX-30 — 20 wt.%, Penetrator — 10 wt.%, And the rest, as coating composition - composition containing, wt.%: pigment concentrate 3-4, 20% polyacrylate film former 30-40, 10% casein 2.5-3.0, the rest is water. When the coating is first fixed, a 15-17% nitroemulsion varnish E-NTs-542 is applied to the skin, and during the second fixing, a composition containing 25 wt.% Of NTs-573 varnish, 37.5 wt.% Butyl acetate and 37.5 wt. .% ethyl alcohol [Reference tanner (Technology) / Ed. N.A. Balberova. - M .: Legprombytizdat, 1986. - P.47-48. Handbook of Tanner (Finishing. Production Control) / Ed. N.A. Balberova. - M .: Legprombytizdat, 1987. - P.41-43].

The disadvantage of this method is that it does not allow to obtain skin with both high performance and protective, namely water-, oil-, petrol-repellent properties.

The technical result of the invention is to increase the operational properties and water-, oil-, benz-, heat resistance of leathers while maintaining their hygiene indicators.

This result is achieved in that in a method for producing leathers, including retanning a semi-finished product with a chrome tanning agent, neutralizing, washing, dyeing, fatliquoring, filling with a water-soluble acrylic polymer, retanning with organic tanning agents, wiring, drying and finishing by applying unpigmented soil, first pressing, double coating composition, the first fixing of the coating, the second pressing and the second fixing of the coating, filling with a water-soluble acrylic polymer is carried out after dyeing, retanning with organic tanning agents is carried out before fatliquoring, after the fatliquoring the semi-finished product is additionally filled with 20% aqueous dispersion of a copolymer of butadiene, acrylonitrile and methacrylic acid in a ratio of 50: 45: 5 at a flow rate of 3-4% by weight of the semi-finished product, after fatliquoring; as unpigmented soil using a composition containing, wt.%:

40% aqueous copolymer dispersion butadiene, acrylonitrile and methacrylic acids in a ratio of 50: 45: 5 10-20 Penetrator 20-30 Water rest,

as a coating composition is a composition containing, wt.%:

Pigment concentrate 5-6 40% aqueous copolymer dispersion butadiene, acrylonitrile and methacrylic acids in a ratio of 50: 45: 5 20-30 30% aqueous polyurethane dispersion 5-10 20% casein 5-10 Water rest,

the first fixing of the coating is carried out by a composition containing, wt.%:

30% aqueous polyurethane dispersion 40-50 Pigment concentrate 1-2 Water rest,

the second fixing coating - composition containing, wt.%:

Perfluorocarbonyl silicone amide acids of the formula C ₃ F ₇ OCF (CF ₃ ) CF ₂ OCF (CF ₃ ) CONH (CH ₂ ) ₃ Si (OC ₂ H ₅ ) ₃ 1-5 Nonionic Fluorocarbon surface-active substance formulas C ₆ F ₁₃ CONH (CH ₂ CH ₂ O) _n H, where n = 6-8 0.1-0.5 Water rest,

the first pressing is carried out between two applications of the coating composition, and the second pressing is after the second coating fixation. In this case, dyeing, filling with a water-soluble acrylic polymer, retanning with organic tanning agents, fatliquoring and additional filling are carried out in one bath.

A distinctive feature of the proposed method is that filling with a water-soluble acrylic polymer after dyeing, retanning with organic tanning agents before fatliquoring, additional filling of the semi-finished product after fatliquoring with an aqueous dispersion of a copolymer of butadiene, acrylonitrile and methacrylic acid in a ratio of 50: 45: 5 (BAM) in one bath , as well as leather finishes with the proposed compositions based on the BAM copolymer, polyurethane and organosilicon perfluorocarboxylic acid amide with the stated ratio These components make it possible to obtain a synergistic effect of increasing the strength, water, oil, benz, and heat-resistant properties of the skin, as well as the resistance of the coating to repeated bending, dry and wet friction, while maintaining their hygiene indicators.

Additional filling of the semi-finished product for less than 20 min with a 40% aqueous dispersion of BAM copolymer obtained at other monomer ratios other than 50: 45: 5, in an amount of less than 3% by weight of the semi-finished product, as well as finishing the leather by applying unpigmented soil, coating composition, first and the second coating fixer, with other qualitative and quantitative ratios of components other than those declared, does not allow to obtain a synergistic effect of increasing the operational and protective properties of the finished leather while maintaining their hygienic indicators.

Additional filling of the semifinished product for more than 30 min with a 40% aqueous dispersion of BAM copolymer at a flow rate of more than 4% by weight of the semifinished product is impractical, since there is no further strengthening of the effect.

As a water-soluble acrylic polymer when filling leathers, Polinap 101, Polinap 105, Polinap SM / 2 brand preparations based on acrylic acid polymers with a molecular weight of 30,000-65,000 neutralized with alkali, with a mass fraction of the main substance of 30-35% and other polymers are used. .

The BAM copolymer is prepared by emulsion polymerization. The duration of dosing of monomers is 6.0-6.5 hours at 80-85 ° C. The loading of monomers is carried out in the following sequence: first, butadiene and acrylonitrile are introduced, and after 3.0-3.5 hours from the start of synthesis, methacrylic acid is added. The ratio of monomers in the copolymer is 50: 45: 5, respectively.

The composition of unpigmented soil is prepared by sequential mixing of a 40% aqueous dispersion of BAM with water and penetrator. Isopropyl alcohol, Ammolan IP (BASF), PP-8620 (Pielcolor), EE-8060 (Pielcolor) and others are used as penetrator. The coating composition is prepared as follows: a 40% aqueous dispersion of BAM is successively mixed with water and a 30% aqueous dispersion of polyurethane. 20% casein solution and pigment concentrate are gradually added to the resulting mass with thorough stirring. Aquapol-10 (TU 2251-373-10488057-2004), Astacin Top EE-US, Astacin Finish PUMN TF (BASF) are used as a polyurethane dispersion. and others.

The composition of the first fixative is prepared by sequentially mixing a 30% aqueous dispersion of polyurethane with water and a pigment concentrate.

The composition of the second fixer is prepared as follows

The organosilicon perfluorocarboxylic acid amide (CAPF) is sequentially mixed with a nonionic fluorocarbon surfactant (Fluorosurfactant) and water.

KAPF receive as follows:

102 g (0.2 mol) of C ₃ F ₇ OCF (CF ₃ ) CF ₂ OCF (CF ₃ ) COOCH _{3 are} added to a flask with a stirrer, dropping funnel and reflux condenser and 46.2 g (0.21 mol) of NH ₂ (CH ₂ ) are added. ) ₃ Si (OC ₂ H ₅ ) ₃ . The contents are stirred at room temperature for 2 hours to obtain a homogeneous mixture, which is subjected to distillation, highlighting the fraction with T _bale = 140-144 ° / 1 mm, yield 98%).

According to NMR ¹ H and ¹⁹ F, the compound has the structure C ₃ F ₇ OCF (CF ₃ ) CF ₂ OCF (CF ₃ ) CONH (CH ₂ ) ₃ Si (OC ₂ H ₅ ) ₃ , n _D ²⁰ = 1.3550, d ₄ ²⁰ = 1.4248 g / cm ² .

Fluorine-surfactant is obtained as a result of the reaction of perfluoroenanthic acid amide CF ₃ (CF ₂ ) ₅ CONH ₂ and ethylene oxide according to the scheme:

C ₆ F ₁₃ CONH ₂ + nCH ₂ CH ₂ O → C ₆ F ₁₃ CONH (CH ₂ CH ₂ O) _n H, where n = 6-8.

The method is as follows:

Prefabricated leather for upper shoes obtained by the standard method for the production of chrome tanned leathers of different thicknesses and assortment for upper shoes and lining from cattle skins (approved on 11/22/1983), after retanning with a chrome tanning agent, neutralizing and washing, it is dyed at a consumption dyes 2-3% by weight of the semi-finished product, g.k. 0.5-0.7 and a temperature of 40-45 ° C for 40-45 minutes Then, in the same bath, filling is carried out for 30-40 minutes with a water-soluble acrylic polymer in an amount of 4-5% by weight of the semi-finished product, retanning for 50-60 minutes with a mixture of synthetic (Relugan D, Relugan S, Basyntan SL, DFPM-2 according to TU 17-06-164-95, ATP according to TU 13-7308001-389-85, etc.) and vegetable (mimosa, quebracho, chestnut) tanning agents at their consumption of 4-5% by weight of the semi-finished product. Fatliquoring for 50-60 minutes is carried out at Zh.K. 1.2-1.3, a temperature of 60-65 ° C and a consumption of fatliquoring materials of 8-9% by weight of the semi-finished product. As fatliquoring materials, ready-made compositions based on natural and synthetic fats are used, for example, Universal-N, Universal-S, Extra, Triamol N according to TU 2484-052-00302267-2000, SMX-E, SMX-470 according to TU 2484-013- 222-84-995-99 and others. After that, in the same bath, additional filling is carried out for 20-30 minutes with 40% aqueous dispersion of BAM in the amount of 3-4% by weight of the semi-finished product. After washing, wiring and drying, the skin is subjected to finishing processes and operations using known technologies, depending on the type of finish. When coating dyeing on the skin is applied unpigmented soil containing, wt.%: 40% aqueous dispersion of copolymer BAM 10-20, penetrator 20-30, the rest of the water, apply a coating composition containing, wt.%: Pigmented twice with intermediate pressing concentrate 5-6, 40% aqueous dispersion of a BAM copolymer 20-30, 30% aqueous dispersion of a polyurethane 5-10, 20% casein 5-10, the rest water. The resulting coating is fixed first with a composition containing, wt.%: 30% aqueous dispersion of polyurethane 40-50, pigment concentrate 1-2, the rest of the water, and then with a composition containing, wt.%: KAPF 1-5, Fluorine-surfactant 0 , 1-0.5, the rest of the water, after which the skin is repeatedly pressed.

The compositions of the finishing compositions of the examples are presented in table 1.

Example 1. Prefabricated leather for upper shoes, obtained by a standard method, after retanning with a chrome tanning agent, neutralizing and washing, is dyed at a consumption of dyes of 3% by weight of the semi-finished product, g.k. 0.7 and a temperature of 45 ° C for 40 min. Then Polynap 101 is introduced into the same bath in an amount of 4% by weight of the semi-finished product, after 30 minutes a mixture of Quebracho and synthetic tanning agent DFPM-2 is added to the treatment solution at a flow rate of 5% each by weight of the semi-finished product. After 60 minutes, hot water is added to the bathtub and fatliquoring is carried out with the SMX-470 composition in the amount of 9% of the mass of the semi-finished product with liquid 1.2 and a temperature of 60 ° C for 60 minutes After that, a 40% aqueous dispersion of BAM copolymer is introduced into the bath in an amount of 3% by weight of the semi-finished product and additional filling is carried out for 20 minutes. After washing, wiring and drying, the declared finishing compositions are applied to the skin with a natural front surface: unpigmented soil at a flow rate of 60 g / m ² , a coating composition is applied twice with intermediate pressing at a flow rate of 100 and 80 g / m ² , the coating obtained is fixed with the first composition at a flow rate of 60 g / m ² , then the second at a flow rate of 60 g / m ² (see table 1, example 1) and re-pressed.

Example 2. Prefabricated leather for upper shoes, obtained by a standard method, after retanning with a chrome tanning agent, neutralization and washing are treated as in example 1, but additional filling with 40% aqueous dispersion of BAM copolymer at a flow rate of 3.5% by weight of the semi-finished product is carried out for 25 minutes. The compositions of the finishing compositions are presented in table 1, example 2.

Example 3. Semi-finished leather for upper shoes, obtained by a standard method, after being retaned with a chrome tanning agent, neutralized and washed, is treated as in example 1, but additional filling with 40% aqueous dispersion of BAM copolymer at a flow rate of 4% by weight of the semi-finished product is carried out for 30 minutes. The compositions of the finishing compositions are presented in table 1, example 3.

Example 4 (control). Prefabricated leathers for upper shoes, obtained by a standard method, after retanning with a chrome tanning agent, neutralization and washing are treated as in example 1, but additional filling with 40% aqueous dispersion of BAM copolymer at a flow rate of 2.5% by weight of the semi-finished product is carried out for 15 minutes. The compositions of the finishing compositions are presented in table 1, example 4.

Example 5 (control). Prefabricated leathers for upper shoes, obtained by a standard method, after retanning with a chrome tanning agent, neutralization and washing are treated as in example 1, but additional filling with 40% aqueous dispersion of BAM copolymer at a flow rate of 4.5% by weight of the semi-finished product is carried out for 35 minutes. The compositions of the finishing compositions are presented in table 1, example 5.

Quality indicators of the obtained leathers and skins of the prototype are presented in table 2.

The strength properties of the leathers were determined according to GOST 938.11, the resistance of the coating to repeated bending according to GOST 13868, the resistance of the coating to dry and wet friction according to GOST R 52580, the adhesion of the coating to dry and wet skin according to GOST ISO 11644, the welding temperature according to GOST 938.25.

Indicators of hygienic and hydrophobic properties of leathers were obtained as a result of tests conducted on the device PVD-2 according to GOST 938.22.

Oil and petrol resistance of the skin was determined by the methods described in the book: Danilkovich A.G., Chursin V.I. Workshop on chemistry and technology of leather and fur. - M., 2002 .-- 415 p.

Using the proposed method allows to obtain water-, oil-, benz-, heat-resistant leather with high performance properties while maintaining their hygiene indicators.

Table 1 Composition Components The content of the components according to the examples, wt.% one 2 3 four 5 Unpigmented pound 40% BAM water dispersion 10.0 15.0 20,0 9.0 21.0 Penetrator 20,0 25.0 30,0 19.0 31,0 Water 70.0 60.0 50,0 72.0 48.0 Coating composition Pigment concentrate 5,0 5.5 6.0 4,5 6.5 40% BAM water dispersion 20,0 25.0 30,0 19.0 31,0 30% aqueous polyurethane dispersion 5,0 7.5 10.0 4,5 10.5 20% casein 5,0 7.5 10.0 4,5 10.5 Water 65.0 54.5 44.0 67.5 41.5 First fixer 30% aqueous polyurethane dispersion 40,0 45.0 50,0 39.0 51.0 Pigment concentrate 1,0 1,5 2.0 0.5 2.5 Water 59.0 53.5 48.0 60.5 46.5 Second fixer KAPF 1,0 3.0 5,0 0.5 5.5 Fluorine surfactant 0.1 0.3 0.5 0.05 0.55 Water 98.9 96.7 94.5 99.45 93.95

Claims (2)

1. A method of producing leathers, including retanning a semi-finished product with a chrome tanning agent, neutralizing, washing, dyeing, fatliquoring, filling with a water-soluble acrylic polymer, retanning with organic tanning agents, wiring, drying and finishing by applying unpigmented soil, first pressing, double coating, first fixing the coating , second pressing and second fixing of the coating, characterized in that the filling with a water-soluble acrylic polymer is carried out after dyeing, doubled organic tanning is carried out before fatliquoring; after the fatliquoring, the semi-finished product is additionally filled with 20% aqueous dispersion of a copolymer of butadiene, acrylonitrile and methacrylic acid in a ratio of 50: 45: 5 at a flow rate of 3-4% by weight of the semi-finished product after 20-30 min unpigmented soil using a composition containing, wt.%:
40% aqueous copolymer dispersion butadiene, acrylonitrile and methacrylic acids in a ratio of 50: 45: 5 10-20 penetrator 20-30 water rest,
as a coating composition is a composition containing, wt.%:
pigment concentrate 5-6 40% aqueous copolymer dispersion butadiene, acrylonitrile and methacrylic acids in a ratio of 50: 45: 5 20-30 30% aqueous polyurethane dispersion 5-10 20% casein 5-10 water rest,
the first fixing of the coating is carried out by a composition containing, wt.%:
30% aqueous polyurethane dispersion 40-50 pigment concentrate 1-2 water rest,
the second fixing coating is carried out by a composition containing, wt.%:
organosilicon perfluorocarboxylic acid amide of the formula C ₃ F ₇ OCF (CF ₃ ) CF ₂ OCF (CF ₃ ) CONH (CH ₂ ) ₃ Si (OS ₂ H ₅ ) ₃ 1-5 nonionic fluorocarbon surfactant the formula C ₆ F ₁₃ CONH (CH ₂ CH ₂ O) _n H, where n = 6-8 0.1-0.5 water rest,
the first pressing is carried out between two applications of the coating composition, and the second pressing is after the second fixing of the coating. 2. The method according to claim 1, characterized in that the dyeing, filling with a water-soluble acrylic polymer, retanning with organic tanning agents, fatliquoring and additional filling are carried out in one bath.