DD296705A5 - METHOD FOR THE FUNGICIDAL AND ANTIBACTERIAL TREATMENT OF SKIN AND THUS TREATED BEEUTH - Google Patents

Abstract

Method for the antifungal and/or antibacterial treatment of hides. This method consists in treating these hides with a bath containing a lanthanum or cerium salt, for example a lanthanum acrylate.

Description

description

The present invention relates to a method of treating hides and the hides so treated.

In particular, it relates to a method which ensures their better biological preservation, especially in the course of their processing before or after tanning.

At present skins are generally available in various forms:

- unprocessed (salted, in brine, salted dry and fresh)

in the pickled state (treatment with a solution of an acid in the presence of salt)

in reversibly pre-tanned state (B.S.H. or B.S.S., for example wet white (wet white), dry white (dry white)

- in tanned state (for example by a chromium treatment

- as a semi-finished product (called "stain" [stained])

- or in the final state.

These skins are often transported or stored in premises which are not suitable for their preservation, in particular moisture and favorable climatic conditions favor bacterial infestation and / or fungal infestation of the skins.

The various treatment solutions used at each stage of processing the hides may have an antibacterial or fungicidal action. However, this is not enough to ensure sufficient protection.

The use of products or compositions comprising compounds having a fungistatic or antibacterial activity, such as, for example, tri- or pentachlorophenols, p-m-cresol, o-phenylphenol and their sodium salts, the derivatives of benzothiazole (for example TCMTB) has already been proposed for this purpose. , Isothiazolones and metal salts such as the zinc or copper salts.

These particular products have disadvantages because they are generally difficult to remove. For example, if the skins are treated with such products before or during the water treatments, they will be present in the wastes incurred in the course of skin treatment, such as shaving. These polluted waste can not be reused, especially for collagen production.

In addition, these special products are found in the treated wastewater of the hides, resulting in unacceptable pollution. In addition, these products may have a toxic effect on the treatment processes of the effluents (biological treatment) carried out in the water purification tanks.

Furthermore, these products may also be troublesome to the skin, for example after tanning.

The object of the invention is, in particular, to avoid these disadvantages by providing a method of treating skins Protection against fungal or bacterial attacks is proposed that in all process stages or steps of the Skin treatment can be applied. For this purpose, the invention proposes a treatment method for skins for protection against fungal and / or bacterial attacks

which comprises treating in a treatment bath containing at least one lanthanum or cerium salt.

Lanthanum or cerium salt is any water-soluble salt such as mineral salts such as nitrates, chlorides, Sulfates or the organic salts or organo-sulfonic acid or gluconates. According to a preferred embodiment of the invention, the lanthanum or cerium salts are organic salts which differ from a Vinylcarboxylic acid, for example, acrylic acid and methacrylic acid, deduce. The salts preferred according to the invention are the acrylates and methacrylates of lanthanum. The hides are treated with a lanthanum or cerium amount expressed as oxide between 0.02% and 1.25%, and

preferably between 0.04% and 1.25%.

These percentages correspond to the amount of the compound, for example, the lanthanum (expressed as oxide), the Treatment of 100kg intestine is added. By intestinal skin is meant a skin that is depilated and of fats and Epidermis is cleaned. The percentages given below in the text always correspond to those for the treatment of 100kg of intestinal membrane

used product quantity, unless otherwise noted.

When the salt is a salt of the vinylcarboxylic acid, free vinylcarboxylic acid is advantageously added to the treatment solution. According to another embodiment of the invention, the amount of vinyl anions or of vinylic acid in terms of

free vinyl acid, advantageously between 0.5% and 5% and preferably between 1% and 3%, based on the intestinal membrane.

This treatment bath may be alone or in combination with a skin treatment bath such as one Pickel-, Gerb- or Vorgerbbad, wiez. B. BSH or BSS bath, for example, in FR-PS 2610643 of the Center Technique Cuir Chaussure et Maroquinerie are described. This fungicidal and antibacterial treatment bath is particularly suitable for the treatment of tanned hides

to protect these harmful molds against them.

Thus, the treatment bath according to the invention protects the skins against attack by fungi, such as, for example, Aspergillus niger, Penicillium funiculosum, Rhizopus nigricans, Trichoderma viride or the bacteria Bacillus subtilis and Escherichia coli. Another advantage of the method according to the invention is the fact that the treatment agent does not occur

irreversible manner attaches to the skin fiber and therefore can be easily removed by washing.

Thus, their subsequent treatments are not affected. Furthermore, lanthanum or cerium are not pollutants and therefore can remain in the effluents. In addition, the residues of the vinyl monomers (acrylic or methane acrylic) are readily polymerizable, this polymerization

inhibits the interfering influence of these monomers.

The inventive method can be applied in any known manner, for example by impregnation in one Treatment bath when passing through a Gerbfaß. The invention also relates to treated by the process according to the invention and lanthanum and / or cerium

containing skins.

According to another feature, the treated skins contain 0.02% to 1.2% lanthanum or cerium, expressed as Weight ratio of dry matter, ie after drying in a convection oven for 6 hours at 105 ⁰ C and

drying to a constant weight at this temperature.

The treated hides also contain vinyl radicals in either monomeric or polymerized form. Further details, advantages and objects of the present invention will become apparent from the following examples

explained in more detail.

- A first series of experiments was carried out with a completely decalcified bovine skin.

This skin was cut and divided into pieces weighing 2000g. Each piece has been treated with a pickle acid solution, the composition of which is given below:

- Sample 1, control experiment

Pickelbad: 100% water, 10% NaCl, 1.5% sulfuric acid, pH 2.8. The treatment lasted 3h. These percentages indicate the amount of compound added per 100 kg of intestinal membrane. The same applies to the following examples.

- Sample 2

Pickelbad: 100% water, 20% NaCl, 1.5% sulfuric acid, 1.96% lanthanum nitrate (0.725% of La ₂ O ₃ ), The treatment lasted 3h.

- Sample 3

A solution of lanthanum acrylate and acrylic acid containing 172.8 g / L of La ₂ O ₃ and 476.3 g / L of acrylic acid was placed in a pickle bath containing 100% water and 10% salt to give a concentration of acrylic acid of 2% and La ₂ O ₃ of about 0.725%.

The skin was treated at pH 5.8 for 3 hours.

These samples were stored in a protective container at 18 to 20 ° C and a relative humidity of 85%. Under these storage conditions, mold marks appeared on Control 1 after 18 days of storage, while Samples 2 and 3 showed no change.

- A second series of experiments was carried out with a cow skin, which was pickled in a pickling bath containing 100% water, 5% sodium chloride and 1.5% sulfuric acid.

The skin was split into strips which were subsequently treated in stabilizing baths to obtain BSH skins. This stabilization treatment consisted in the addition of 2% (weight per gut) aluminum polychlorosulphate (0.16% in terms of Al ₂ O ₃ ) to the pickle solution after neutralization in the form of an aqueous solution having a basicity of 55%, a degree of desulfating of 82 % and an Al ₂ O ₃ content of 8.3%, which was obtained by the method described in EP-A-218487.

In the course of this treatment, a fungicidal and / or antiseptic treatment agent was added to the stabilizing bath neutralizing the bath to obtain a pH of about 4.

- Strip No. 1

Without fungicidal and / or antiseptic treatment

- Strip No. 2

A solution containing lanthanum acrylate and acrylic acid (172.8 g, expressed as La ₂ O ₃ and 476.3 g of acrylic acid) so that 0.4%, expressed as La ₂ O ₃ , by weight of the intestinal (skin weight) was present ,

- Strip No. 3

23.8 g of lanthanum acrylate was added to the stabilizing bath to give a content of 0.04%, expressed as La ₂ O ₃ , based on the weight of the intestine.

- Strip No. 4

A classical antiseptic agent sold under the trade name "Busan 30" was added to obtain a concentration of 0.07% by weight of the intestinal weight.

These different strips were placed in a humidity chamber with 85% humidity and at a temperature of 18 to

Stored 20 ⁰ C.

After 11 weeks storage, only control strip # 1 was on the leather side across the entire thickness, as well as on

The split hair side affected by mold.

In addition, some of these strips were subjected to tanning treatment by means of chromium or vegetable tanning. These tanning tests have shown that the treatment of the hides with a bath according to the invention, the tanning conditions

and the properties of the obtained tanned hides are not affected.

A lanthanum addition to the B.S. H.-Häuten has shown that the lanthanum content, based on the dry matter, 0.07% for Strip No. 3 and 0.46% for Strip No. 2. Hides were tested for mold in petri dishes on small leather samples that were microbial

in the ratio of 1 × 10 ^s cells per cm ^{2 of} leather were inoculated.

The thus inoculated sample was placed in an agar-agar medium, which was poured into a petri dish and even with a

corresponding microbial solution was inoculated.

The whole was placed in an oven kept at a constant temperature at 30 ^° C. for incubation. Mold development on the leather and agar-agar milieu was observed. In a first series of experiments, a leather tanned with chromium salts, usually called "wet-blue", was named

to a solution containing an antibacterial compound according to the invention and for comparison with a known and commonly used compound, namely a sold under the trade name "BUSAN"

Benzothiazole derivative, impregnated. The lanthanum content, expressed as lanthanum oxide, or the Busangehalt was 0.4%. The results are shown in the following table:

Antibacterial 3Tagen 6Tagen % Infestation of the sample 16 days 27 days composition 50% 100% 12 days 100% 100% 10% 60% 100% 80% 80% Lanthanxylolsulfonat 5% 60% 80% 80% 80% Lanthangluconat 5% 60% 80% 100% 100% lanthanum 0% 5% 80% 40% 60% Lanthanacrylat 40% Lanthanacrylat + 0% 5% 5% 15% acrylic acid 0% 0% 5% 0% 0% Busan 0%

Another series of experiments was carried out according to the same procedure but using hides pre-tanned with an aluminum solution, referred to as BSH skin.

It was observed that the skin impregnated with 0.4% lanthanum (expressed as La ₂ O ₃ ) and lanthanum acrylate was 75% infected after 6 days and that 50% was impregnated with a solution of lanthanum acrylate in acrylic acid after 10 days and 75 % was infested at 24 days, whereas skin containing no antibacterial agent was 100% infected at 3 days. These tests were also performed with skins that had been subjected to vegetable tanning. It has been found that the mixture of lanthanum lactate and acrylic acid makes it possible to delay mold attack by a few days (about 6 days) under the test conditions, while the untreated skins are infested very rapidly (after 1 day).

Claims (12)

1. A process for the fungicidal and antibacterial treatment of hides, characterized in that it consists of their treatment in a treatment bath containing at least one lanthanum or cerium salt. 2. The method according to claim 1, characterized in that the lanthanum or cerium salt is a water-soluble or dispersible salt selected from the group comprising the nitrates, halides, sulfates and organic salts. 3. The method according to claim 2, characterized in that the organic salts of Lathans or Cers are salts of a vinylcarboxylic acid or an organosulfonic acid or gluconates. 4. The method according to claim 3, characterized in that the vinylcarboxylic acid salts are acrylic or methacrylic acid salts. 5. The method according to claim 4, characterized in that the treatment bath contains a free vinylcarboxylic acid. 6. The method according to any one of the preceding claims, characterized in that the added to treat the skins amount of lanthanum or the ether, expressed as oxide, between 0.02% and 1.25% and preferably between 0.04% and 1, 25%, based on the intestinal membrane. 7. The method according to any one of the preceding claims, characterized in that the added for the treatment of hides amount of vinyl carboxylate anion and / or vinyl carboxylic acid, expressed as free vinyl carboxylic acid, between 0.05% and 5% and preferably between 1% and 3% on the intestine, amounts to. 8. The method according to any one of the preceding claims, characterized in that the fungicidal and antibacterial treatment bath is combined with one of the treatment baths for skins. 9. The method according to any one of the preceding claims, characterized in that it consists of the treatment of tanned or pre-tanned hides. 10. hides, characterized in that they contain lanthanum or cerium. 11. skins according to claim 10, characterized in that they contain vinyl groups in monomer or polymerized form. 12. skins according to claim 10 or 11, characterized in that the lanthanum or cerium content, expressed as oxide, between 0.04% and 1.2%, based on the dry matter.