DE1288232B - Preservatives for skins or pelts - Google Patents

Description

Treated Success.

On the basis of the known state of the art, it was also not to be expected that by adding

would achieve, since it was found that ζ. Β. Disinfectants based on phenols or quaternary ammonium bases lose their effectiveness when salting hides.

It was also known that in addition to the stains caused by bacteria, e.g. B. Red and Violet discolouration, also often spots based on mineral salts, so-called incrustation spots, occur.

cetenarten), occurring discolouration (red and 5 bination with sodium chloride for preserving hides violet discolouration etc.) as well as the formation of tion. The person skilled in the art still had to be able to prevent mineral salt stains. assume that such a combination

So far one has had the hides or skins with the unsuitable ones, since already in several literary divisions Mixtures of sodium chloride and put on the decrease in effectiveness of the bacteriostatic with salt, fungicides and / or disinfectants used to a greater or lesser extent effective means without satisfactory. In the case of the preservation of skins

Among other things, there is the very specific problem of combating halophilic bacteria against them many microcides, which are quite useful in other disinfectant applications in addition to sodium chloride in the field, fail. It was Salting of hides has also been known to have a satisfactory result in the preservation of hides the fixation of any antiseptics added to the salt by the skin's collagen their effectiveness is often reduced (compare 20, for example, Chemical Abstracts, 55 [1961], 27931 e: »Conservation of hides by salting ", or I. J u 11 i e η, Bull. assoc. franc, chimistes inds. cuir et doc. may be. et tech. inds. cuir, 23, pp. 225-230 [1961]). Compared to the so far almost exclusive in technical practice

These incrustation or salt stains are the use of soda and naphthalene as additives The skin con-containing agent according to the invention has deposits of water-insoluble phosphorus-to-skin salt Calcium and / or magnesium compounds have the advantage that this is very uncomfortable Skin fiber mesh. A distinction is made between naphthalene with a persistent smell by one Salt-suitable not or only weakly smelling Redukflecken consisting mainly of calcium phosphate several types, e.g. B. meat side, middle 30 üonsmittel in combination with organotin shifting or scar salt stains, while those can be replaced by ties. In the treatment Magnesiumphosphaieverlagerung occurring salt of the skins with naphthalene results from the practically only stains on the so-called salt possibility of health damage that speck, d. H. on incrustations of magnesium a maximum working concentration of werammonium phosphate is observed in between and scarring must. These disadvantages can be caused by the restrict. Due to the occurrence of these skin preservatives according to the invention at the same Bacteria and minerals caused discoloration or even an improved preservative effect or stains are avoided during the preservation.

If the later further treated and finally suitable reducing agents, which are subjected to a quality reduction in the skin, which is tanned during salting, do not interfere with the process, they are either completely or for certain purposes nitrites such as sodium nitrite, bisulfites such as sodium (suede , Glove leather) makes useless. bisulfite, benzenesulfinic acid or ascorbic acid or the aim and object of the invention was therefore to provide another known reducing agent. To find by the means that both the stains occurring by bacteria addition of hexamethylenetetramine or a com and the bination of hexamethylenetetramine caused by minerals 45 with other stains and incrasting of skins reducing substances such. B. with SO ₂ , or skins are prevented. also a stabilization and reinforcement of the

It has now surprisingly been found that organotin compound is achieved. Another Organotin compounds in a mixture with increased Na activity can also be achieved with the antrium chloride and an addition of a reducing agent of small amounts of a surface-active agent by means of and / or hexamethylenetetramine in the case of one substance of the polyglycol type. salting of hides their bactericidal or bacterial The preservative according to the invention for Do not lose static effect while the skins or pelts are thus made of sodium chloride Prevention of mineral seed stains or incrustations and, in each case based on sodium chloride, 0.003 to Rip staining likely on a colloidal 55-10 weight percent, preferably 0.01 to 1 weight mix Action of together with Na percent, an organotin compound of alltrium chloride applied inorganic compounds fertilize and the addition of the reducing agent j ^ iv ^ i

and / or hexamethylenetetramine, surprise- \, /

thus it was found that the effectiveness was 60 Sn

of the tetravalent organotin compounds R ^{IU //} ^ R ¹ '

can be strengthened by a reducing agent and / or hexamethylenetetramine, whereby at the same time where R ¹ , R ", R ^m and R ^{IV are} identical or different, a stabilization of the tetravalent organic orga-tin compounds bound to the tin via carbon atoms occurs and the effect of the niche occurs Mean residues which can be replaced up to a maximum of three tetravalent organic tin compounds even by organic or inorganic groups that are not bound via carbon atoms and are retained for a longer period of time or storage, and 0.03 to 1 percent by weight, preferably 0.2

up to 0.5 percent by weight, of a reducing agent and / or 0.009 to 30 percent by weight, preferably 0.03 to 3 percent by weight, hexamethylenetetramine and optionally a small amount of a surfactant of the polyglycol type.

Besides sodium chloride, e.g. B. in the form of rock salt, sea salt, saline salt or vacuum salt, can the preservative also includes other known mineral preservative salts or preservative salt mixtures, z. B. sodium chloride-sodium sulfate mixtures contain.

Organotin compounds of the above Formula are e.g. B. tri-n-butyltin acetate, benzoate, salieylate, dibutyltin succinate, triethyltin laurate. Bis (iribiityl tin) oxide, bis (triethyltin) sulfide, Octyizinntrihexoat, Tribenzylphenyltinn, Träthyltinnphenoxid or triisopropyltin pentachlorophenolate.

Particularly good results are achieved when the hides or skins are sawn with a preservative based on sodium chloride, which has an addition of 0.01 percent by weight of tri-n-butyltin acetate, 0.5 percent by weight of sodium nitrite and 0.5 percent by weight of hexamethylenetetramine with a sulfur dioxide content of 7.4 ° / ₀ .

The interim preservation of the hides from falling after slaughter to further processing (e.g. tanning process) should as much as possible preserve the skin's condition and Ensure easier further processing and good quality of the skins. Be before preservation the individual ingredients are intimately mixed with Sak and the mixture z. B. applied by scattering on the skins. As the effectiveness of each component is not influenced by the type of application, the mixing is mainly done in order to to achieve a more comfortable handling.

Wet conservation is also possible. The sodium chloride can also be used with known anti-caking agents as well as the usual denaturing agents, e.g. soda, are added, an addition of 3% soda is particularly advantageous. The stabilized organotin compounds do not interfere with the processing that occurs after the preservation. You have beyond that the advantage that they themselves do not lose their effectiveness in the subsequent softening process ond that they inhibit the fluid processes, which under certain circumstances progress very quickly in the softening process.

Experimental series for preserving skins:

To carry out the test series, unchanged and blotchy salted calf skin, z. B. Skin with red and violet discoloration, cut into 100 lOOtnra pieces. The pieces of the stain-free (unchanged) skin were then prepared in various ways (see Table I) and each brought together with a piece of stained skin in such a way that the flesh sides lay on top of one another. These pairs of pieces of skin were tightly rolled up for storage, tied with rubber rings and kept in a screw-top jar. In this way it was achieved that the pieces of hide are stored in an atmosphere like those in the hide cellars

ίο of the hides, where the salted hides lying in stacks prevails.

The modified (blotchy) skin used looked uniformly bright red on the flesh side and was littered with countless dark red to purple point-like spots that were stuck in the skin, while the bright red color seemed more attached to the sodium chloride crystals. In Table I are the test results are summarized. Only the surcharges are given which are used to combat it serve to discolour red and purple. The amount of sodium chloride required for salting is included Use 500 g per kilogram of fresh skin.

Table II shows tests carried out with blotchy skin; it interested here the extent to which an existing infestation can be eliminated. The table shows that existing red discoloration can be permanently removed.

In a further series of experiments, the process of salting in was imitated. Fresh raw veal skin was sprinkled with table salt on the meat side, rolled up and laced. At the same time was a Pieces of blotchy skin rolled up with it. The amount of common salt used corresponds to half of the Skin weight and contains the following additives:

1. pure table salt,

2. 0.001% tri-n-butyltin acetate,

3. 0.01% tri-n-butyltin acetate and 0.5% sodium nitrite,

4. Containing 0.01% tri-n-butyltin acetate, 0.5% sodium nitrite, 0.5% hexamethylenetetramine of sulfur dioxide of 7.4%.

An addition of 0.001% tri-n-butyltin acetate to the Table salt is not enough to cause red and purple discolouration to prevent. The sample looked particularly good when it was salted with table salt which was an addition of 0.01% tri-n-butyltin acetate, 0.5% sodium nitrite and 0.5% hexamethylenetetramine with a sulfur dioxide content of 7.4%. } it was by far the worst condition the skin sample that had been treated with pure table salt.

Table I.

Attempts sr preserving calfskin

attempt

Treatment cifcr healthy, geü> lz: ne »

Skin with 500 g sodium chloride im

1 kg skin, additives of

0.0750 g of ti n -butylziniibenzoai
CU SOu g AlkyiphenylpoIyglykoIiiUier
0.275 g hexamethylenetetramine.
0JKJ75 g sulfur dioxide.

Appearance of the prepared skin
five weeks of contact with blotchy skin

no infestation, skin soft, supple
Color: whole area light

continuation

attempt Treatment of the healthy, salted
Skin with 500 g of sodium chloride for
1 kg skin, additives of Appearance of the prepared skin
five weeks of contact with blotchy skin 2 0.0375 g tri-n-butyltin benzoate no infestation, skin soft, supple 0.0750 g of alkylphenyl polyglycol ether Color: whole area light 0.1896 g formaldehyde 0.1188g hexamethylenetetramine 0.0038 g of sulfur dioxide 3 0.0750 g of tri-n-butyltin benzoate no infestation, skin soft, supple 0.1500 g of alkylphenyl polyglycol ether Color: whole area slightly gray 0.2375 g of hexamethylenetetramine Parallel attempt to 1 after 6 months of contact 0.0075 g of sulfur dioxide 4th 0.0375 g tri-n-butyl tin benzoate no infestation, skin soft, supple 0.0750 g of alkylphenyl polyglycol ether Color: whole area slightly gray 0.1188g hexamethylenetetramine Parallel experiment to 2 0.0038 g of sulfur dioxide 5 NaCl without additives very strong red and violet coloring

The same results were obtained with the omission of the sulfur dioxide in experiments 1 to 4.

Table II
Attempts to preserve calfskin

Treatment of blotchy, salty skin with quantities given for 1 kg of skin

Condition of the skin at the start of the experiment Appearance of the treated skin five weeks standing time

Washed off with an aqueous solution of 250 g of table salt and the addition of

0.060 g tri-n-butyltin benzoate, 0.120 g alkylphenyl polyglycol ether, 0.300 g formalin,

0.190 g hexamethylenetetramine,

0.003 g of sulfur dioxide and slightly re-salted with pure table salt

Sprinkled with 100 g of NaCl, which contains V _{10 of} the amounts from the previous experiment of tri-n-butyltin benzoate, alkylphenyl polyglycol ether, formalin, hexamethylenetetramine and sulfur dioxide

Treated in places after trial (Table I)

Red discoloration

Red discoloration and a corner purple discoloration

slight red discoloration

Red discoloration skin soft, supple

Color: whole area very light to white

Skin soft, supple
Color: very light to white, purple discoloration has remained

Skin soft, supple

Color: light red coloring (practical

unchanged)

treated area light gray to light; Environment red and faint purple color

Claims (4)

Patent claims: 1. Preservative for hides or skins, characterized in that the preservative consists of sodium chloride and, in each case based on sodium chloride, 0.003 to 10 percent by weight of an organotin compound of the general formula R ^IV III Sn _R II where R ¹ , R ″, R ™ and R ^w mean the same or different organic radicals bonded to the tin via carbon atoms, which up to a maximum of three can be replaced by organic or inorganic groups not bonded via carbon atoms, and 0.03 to 1 percent by weight of a reducing agent and / or 0.009 to 30 percent by weight of hexamethylenetetramine. 2. Preservative for hides or skins according to claim 1, characterized in that the preservative additionally contains a small amount of a surfactant Contains type of polyglycols. 3. Preservative for hides or skins according to claims 1 and 2, characterized in that that it is the organotin compound tri-n-butyltin acetate and / or benzoate and / or -oxyd contains. 4. Preservative for hides or skins according to Claims 1 to 3, characterized in that that there is sodium nitrite and / or hexamethylenetetramine with sulfur dioxide as a reducing agent contains. S. Preservatives for hides or skins according to Claims 1 and 4, characterized in that that it consists of a mixture containing 0.01 percent by weight of tri - η - butyltin acetate, 0.5 weight percent sodium nitrite and 0.5 weight percent hexamethylenetetramine with a Sulfur dioxide content of 7.4 percent by weight, the amounts of the components based on sodium chloride are related, contains. 909 505/1514