Fur finishing

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Three dressers on thin cutting machines

The conversion of the raw hide into leather, i.e. a tanned condition protected from rot, is referred to in the tobacco industry as (fur) dressing or tobacco dressing , in Austrian rough goods dressing , the similar process in the leather industry is called tanning (dressing there: the finishing of the Surface structure). A rare, probably no longer used term for this was lidern.

The further processing such as dyeing, shearing etc. are summarized under the term (fur) finishing or tobacco finishing . Fur trimming consists of removing flesh from the fur and then treating it with tannins and fats .

The fur material

In the tobacco industry, up to 180 animal species are used from the variety of animals. Most of them belong to the classes of predators, rodents and ungulates.

Fur animals are only divided into two classes in the preparation and processing of tobacco products . The pelts that mainly come from the order of predators and rodents are counted as wild goods , such as the sable fur, which is considered to be the most valuable in most times, and the inexpensive fur Kanin, which is widespread worldwide . The sheep ware includes the pelts from the order of the ungulates, which includes all types of lambskin , for example Persian fur and all types of kid . Calf skins and foal skins come from ungulates, but they are still included in the wild. While the wild goods, with a few exceptions, come from older, mostly perennial fur animals, the sheep goods, except for the sheepskins , usually come from young animals that are a few days to weeks old.

Although the chemical structure of the skin is the same for all fur species, age and sex, species and breed as well as the season of the fur require different treatment methods, both in terms of dressing and finishing. The requirement of the further processing furrier is that it should above all be light and quick so that it can be relaxed well and the end product should have the lowest possible weight, which is required today, it should also be tear and puncture-resistant and natural Not discolored fur in the hair. The hair coat must not be adversely affected by the dressing and should be preserved as completely as possible. The skins differ on the one hand by the structure and thickness of the dermis and by the very different coat. So have z. B. beavers, muskrat, nutria, raccoons but also foals have a dense, firm fiber structure of the dermis and therefore require more intensive processing. Lambskins or foxes have a rather loosely structured leather skin. The thickness of the dermis depends mainly on the species, but also on age, sex and the stage of development of the coat. Since the dermis on the trimmed hide is largely responsible for the physical properties, these differences must be taken into account during processing. In addition to the natural colors, different structures and thicknesses can be distinguished in the hair coat. The coat structure results from the ratio of thick and firm guide and guard hairs to the fine hairs of the undercoat. In the case of skins with a fine coat and a lot of undercoat, the risk of matting must be taken into account when preparing. Examples of particularly sensitive types of fur in this context are foxes or long-wool sheepskins.

Certain skins are trimmed using the brushing method, for others only a dipping method with several baths is possible. Some hides are drummed with fat, others are so fat that they have to be washed beforehand, etc. The differences between the individual types of skin are so significant that the dressing and finishing companies often specialize in some types of skin.

The dressing

Preservation by salting
Long pulling the skins on the furrier bench
Repairing butchery cuts with the fur sewing machine
A wild boar rind in the reel
A sheepskin is cleaned of chaff with the hoisting machine

The dressing, the transformation of the skin into a dressed hide, is a more or less permanent tanning (in the leather technical sense a half-tanning). The different designation already expresses that it is a different type of treatment than leather tanning. Since the intensive chemical breakdown of the skin in leather production is not possible, it would lead to damage to the hair, the loosening of the skin fiber structure takes place through increased mechanical processing. In general, the following steps are required to prepare fur skins:

Preliminary work
Pre-soak
Soft
Deflate
Washing, degreasing
Pimples
Thin cutting
tanning
Greasing
dry
Degrease
Moist lautering
Fold
Stollen, Bakeln, Milling, wide and long drawing (Witten), stretching
dry
Dry lautering
Comb
Ironing the coat

Preliminary work

Most of the raw material that is processed into fur is preserved by drying. In this condition, the skins are also traded internationally and come to the dresser. For high-quality preservation, the skins are pre-fleshed, stretched and dried. In this condition the raw material can be kept well, but must be stored in a cool, airy and dry place. In the case of such a rot-sensitive product as raw fur skin, the incoming inspection in the finishing shop plays an important role. The raw material must be unpacked immediately and stored loosely. It must be checked for possible damage, for example from mold growth or self-heating due to packaging that is too tight. Frequent disinfection is required against vermin, moths, mice and rats.

The dresser puts together lots for familiarization. For an optimal finishing result, only raw materials of one type and provenance may be incorporated together. Each skin of the batch can be assigned to the customer even after finishing by means of a punch. The storage of the individual order batches takes place in trolleys or conveyor braids, today less from woven baskets, but from cheaper and easier-to-care for plastic. Depending on the customer's requirements, the bellows are cut open or go through the “round” finishing process.

The soft

The switch puts the raw fur back into the swelling state it was in before the preservation. The most important softening agent is water, to which dirt-dissolving, fat-emulsifying and bacteria-inhibiting chemicals are added. The switch is one of the decisive factors for the softness and speed of the trimmed skin, mistakes that are made here can hardly be compensated for later. The pre-soaking takes place in tubs or resting in reels or skin turns, which after soaking the skin, move it from time to time during the remaining soaking. When preparing the fur, it is important to ensure that the fur floats well in the water so as not to become matted. From time to time they are therefore moved slowly, preferably in gentle reels and fur turning.

Enzyme pickling

A possible Enzymbeize causes a loosening of the fiber structure of the skin, it is used in the leather industry for some time.

Deflate

Of the completely sodden skins the subcutaneous tissue with the one in or attached meat and fat parts removed (is Rabatzen , scrape, , tearing ). This happens either on the furrier bench, also known as the dresser or meat bench, or on the tanner tree, which is also common in the leather industry; in large companies today, however, if possible with the more efficient deflashing machine adapted to the material .

Nowadays, the scraping of skins that go to the auctions is usually done with semi-automatic machines in special skin degreasing plants, English scrape stations.

On the furrier bench and on the tanner tree, people work in the riding seat. At the front end there is a vertical post, the stamp, this carries the tunnel at the top. The meat or furrier iron attached to it is bent slightly crescent-shaped and with its sharp side turned away from the worker sitting on the bench. The carcass is stripped off by pulling the skin tightly over the sharpened iron. Another possibility is processing on the thin cutting machine (circular knife).

The laundry

The cleaning effect of the switch is usually not sufficient. In particular, heavily soiled types of fur with a high proportion of natural fat, such as lamb and sheepskins, require additional washing and degreasing. The washing can be done before, but more cheaply after deflaming. The oldest detergents are soaps, but they are practically no longer used because of their relatively poor detergency, low chemical resistance and alkaline pH value (risk of hair damage). Newer, neutrally reacting detergents no longer have this disadvantage. Oil paint is removed with solvents as far as possible, ticks and other mechanical contamination by spraying and scraping. It is carried out in vessels with movement such as a reel, fur turner or soft barrel.

Finishing types

The types of dressing depend on the later use of the fur. Mainly mineral tanning agents based on aluminum and chromium III salts are used. To improve chemical resistance, they are combined with aldehydes or synthetic tanning agents (syntans). Chamois tanning and other tanning, such as vegetable tanning, are of secondary importance for fur finishing, they can only be considered for special cases.

Pimples For these mineral tanning, the skins must be acidified before the actual tanning. This takes place in the pimple, a separate process step. The pimple is made up of different acids such as formic, acetic, lactic, glycolic or sulfuric acid and neutral salt (for example sodium chloride or sodium sulfate). Through their use, the soluble proteins are broken down. In addition to preparing for tanning, the pimple solution loosens the leather fiber structure (skin breakdown). This skin exposure is of great importance for a soft and quick fur coat. The skin breakdown is supplemented by the frequent mechanical processing (stretching, stretching, spreading, baking, etc.) between the chemical processes.

The most popular types of dressing are as follows:

  • Leipzig dressing

The Leipzig dressing (Leipziger Pickel) was once the most frequently used dressing. The skins are treated with table salt and sulfuric acid and then with oxidizable fats. If you wash out the salts and fats again, the leather character is lost again; the Leipzig finish is therefore not waterproof. Since the acids in the pimple are never neutralized, the humidity in the air causes a permanent acid attack on the leather, with the result that the leather decomposes. The pimple is actually a type of preservation (pseudo-tanning), which is therefore generally followed by retanning.

The prepared skins are either coated several times with stronger pimple broths or agitated in weaker broths for 12 to 14 hours and then thrown off well. Then they are thinly cut or folded and if necessary pickled, greased and finished in the usual way.

Since the Leipzig dressing produced the lightest skins at least around the 1970s, it was still used when a particularly light and quick leather was important. By using formaldehyde upstream from around the 1930s, it was possible to get by with considerably thinner pimples and also to produce a coat with sufficient water resistance.

  • Shot preparation

An old type of dressing is the shot dressing, it is similar to the Leipzig dressing. It is based on the formation of mild organic acids through fermentation of a pulp made from crushed barley, salt and yeast in which the skins are layered. With it, a very fine and non-slip leather is produced, which, however, is not waterproof even without an upstream formaldehyde treatment or a corresponding finishing touch. It is particularly suitable for lamb and sheep. Because of the great effort involved, the dressing also takes 4 to 14 days, it has been used rarely for a long time.

  • Fulling

Kinds of fur with a firm skin structure, for which normal greasing is not sufficient, experience a fulling. A major difference to other fatliquoring methods is the type of fatliquor. Whale oils or fats are not soluble in water. They are worked into the skins purely mechanically in crank or hammer rolls. It is therefore not suitable for skins with a fine coat that tends to become matted (e.g. foxes, sheepskins). To a certain extent, the whale oils also have a tanning effect and bind irreversibly to the dermis. This fat dressing takes place after one of the usual types of dressing, in particular the Leipzig dressing.

  • Chrome finishing

Chrome finishing is used for special requirements, both by painting and by dunking. Carpet skins, for example, have a very special strength, skins that are to be subjected to special dyeing methods, the necessary heat resistance. Compared to the Leipziger or alum dressing, the skins dressed in this way have a very good chemical resistance. Even when it is damp, the leather pulls less and the weight of the skins is higher. The chrome finish is also not suitable for all furs due to the gray-green inherent color of the chromium III salts.

In the case of chrome finishing or chrome tanning, the addition of soda gives the chrome compounds a different basicity , possibly in connection with the brief application of a Leipzig finishing. It also serves as a follow-up treatment for other finishing processes. It takes place in the dunking process, in connection with other types of dressing also in the coating process.

  • Alum dressing

The alum finishing is one of the oldest Zurichtverfahren, it is similar in its principle of Leipzig dressing and is also based on the pimple effect, except that instead of sulfuric acid aluminum salts used (potassium alum, aluminum sulfate or other aluminum compounds, sodium chloride, sodium acetate ). It is also somewhat impervious to water. Alaungar pelts are generally a little slower than pelts from Leipzig dressing, but the result fulfills all conditions if they have undergone formaldehyde pretreatment. The splitting off of acids in the leather is much lower than in the Leipzig dressing and the fur is therefore more permanent. When done correctly, the low-acid alum finish results in a non-slip, glacé-like and pure white leather.

The alum dressing is done using the dunking process, in exceptional cases also by brushing in.

  • Dressing with vegetable and synthetic tanning agents

Dressing with vegetable and synthetic tanning agents of various kinds is usually combined. This finishing method has gained in importance, especially for everyday items made from sheepskin and lambskin. A combination of mimo tanning agents with aluminum tanning agents also enables the production of washable and temperature-resistant skins.

Thin cutting and folding

A cattle hide is cut thin in the folding machine

Thick leather skins are cut or folded thin. The dermis should be made thin and as even as possible without losing too much tear resistance. Thin cutting machines are used for smaller pelts and folding machines for larger ones . The essential part of the thin cutting machine is a rotating circular knife. The thickness of the layer to be removed is determined by the setting of the jaws and the pressure exerted by the worker. The thick-leather male rabbit skins are always folded, calf, foal or goat skins are processed with the folding machines that are also common in the leather industry . With all methods it is important that the hair roots are not cut, otherwise the hair will fall out.

Clods

All game hides have different leather thicknesses, which are evened out by thin cutting on the circular knife defeat machine. The stripes of hair that are around 3 to 6 centimeters wide (up to 30 centimeters in rabbit fur) are known as clods. In times of material shortage, these leather strips were collected, retanned and used in their natural or dyed state.

Greasing

All trimmed skins, regardless of the type of trimming, only get softness and resilience through greasing. The fatliquor wraps itself around the leather fibers so that they no longer lie brittle against each other, but slide past each other. The leather feels soft, the tear resistance is increased and the fibers are protected against various chemical attacks.

The industry has special fatliquors available for different applications. The agent must penetrate the skin well, form a bond with the fibers, must not yellow the hair and leather and also not stick the hair together. Licker fats are leather fats that combine with water to form emulsions and leave only minor traces in the hair. They are also used in fur cleaning and in skinning for re-greasing or re-greasing worn furs.

Drying, purifying and expelling

Sheepskin drying
Final inspection of the ready-made red fox skins in front of the lauter tun

After greasing, the skins remain there for a long time, during which the grease envelops the skin fibers and bonds with the leather. Then they are dried. In modern dressing shops this is done in heated drying rooms with circulating air, at temperatures matched to the previous dressing type, earlier by venting on the drying floor.

The hair is now more or less stuck together and the leather is quite stiff. So that the hair gets "play, stand and shine" and the leather becomes soft and swift, the fur is first dampened and then " cleaned " dry (twisted in the barrel with wood flour). The wood flour is then removed in shaking bins and with pounding machines. In addition to the moist lautering and the good lautering, they are subjected to a number of other procedures, which are technically referred to as dragging, pouring, and baking.

Since the large areas in particular were mechanically worked through during the refining process, the edges, the head parts and extremities (claws) must also be loosened by mechanical processing. This work is called expelling. It used to be done in front of the bench iron on the furrier's bench, now with stretching or Bakel machines. These machines can also be used for staking, the final straightening of the skin. Any damage or cracks that may have arisen can be removed by opening and sewing with the fur sewing machine .

Cleaning, stretching and combing, today exclusively by machine, end the finishing process. If necessary, fur finishing can now follow, such as dyeing, scissors, plucking, velvety, napkin and much more.

history

As far as the pelts were not prepared by the farmers and hunters themselves using simple methods, for centuries it was the furriers who did this as part of the entire fur processing. The furrier had to prepare the skins so that he could process them. The resulting expression smoking goods has been preserved up to the present day. In the fur industry, there is no talk of fur tanning, although more and more tanning agents have been used in recent decades.

It is documented from the 16th century that the Breslau furriers only prepared the skins and then sold them to the cap makers . In the 17th to 18th centuries, individual furriers began to specialize. As early as 1630, the Leipzig guild complained "that there are masters who no longer handle a piece of finished goods and those who can no longer prepare a piece of skin". But in 1849 there was supposedly no special fur dresser in Leipzig. However, already thirty years later there were 66 independent dressers and 13 fur dyers in Weissenfels , Rötha , Schkeuditz and various other places near Leipzig.

Around 1900 the consumption of fur goods increased considerably. With the invention of the fur sewing machine and the emergence of fur farming, it was possible to offer furs at generally affordable prices. With the increasing amount of tobacco products produced, fur dressing became industrialized in the 19th century and there was a definitive separation between furriers and smokers . As a result, some of the companies specialized again either in dressing or refining. This specialization continued to the point that some companies only prepared and / or refined certain types of fur. Around 1900, the vast majority of skins were still on the market undyed, but that changed quickly in the first half of the 20th century. The workflow was essentially based on three dressing methods, pure milled dressing, sulfuric acid and salt dressing and alum dressing. The mechanical equipment was mainly limited to lautering and shaking bins as well as washing drums, often washing or rinsing was even carried out in the river. The main tool was the furrier bench. Almost all operations were carried out by hand, which was perfectly suited to the natural, individual product fur. Fatting agents were furrier butter and oil for spreading oil.

The mechanical use of machines, such as the lauter tun and the fulling machine, was initially very sporadic through water power. Of greater importance was the introduction of steam power , which was used more and more since the middle of the 19th century. It increased productivity to a considerable extent and, in contrast to the drive with running water, made it possible to set up the workshops on favorable traffic routes or other useful locations.

The main center of German fur dressing and finishing was located around Leipzig until after the end of the Second World War , as a supplier to what was at times the largest European fur trade center, the Leipziger Brühl . In addition to the proximity to the Brühl, the previously important presence of flowing water or the "right water" (= soft water) was also mentioned as an advantage, as the city area is surrounded by four rivers as a special feature, the Elster, Luppe, Parthe and the Pleiße. The importance of soft water, which ensures a better workflow, changed in 1930 when synthetic detergents and wetting agents, which were largely resistant to hardness builders, were used instead of soap. The term "water workshop" is still in use today in tannery and dressing. The term has been synonymous with all activities and process steps before the actual tanning process since the 18th century. This is where the smells that are inherent in the craft and are not necessarily perceived as pleasant are created. A circumstance that is always unpleasant for the companies and their employees is the uneven distribution of orders over the year. Except in times of economic boom, when this could be partially offset by long delivery times, the seasonal dependency often led to short-time work or unemployment for the dressers.

After the Second World War, large companies also developed, which again operated dressing and finishing together. This was particularly useful for those types of fur that are blinded or dyed, as the color process is often based on the dressing, so that the color refinement is better if the dyer knows about the basics and chemicals of the previous processes. At the time of the extraordinary boom in German fur consumption, vertically structured companies were created that carried out raw fur trade, dressing, dyeing, bleaching, machinage, finished fur trade and manufacture in one hand.

The main difference between today's dressing and the past is, in addition to the extensive mechanization of the work processes, the introduction of modern, much shorter-term tanning processes with better chemical resistance.

After the relocation of fur production, mainly to Asian countries, there are now only a few fur trimmers that have remained in Germany and Europe.

Further machines in the fur trimming shop

Historical finishing equipment of the furrier (1768): The tanner's bench (Fig. 1); the fox or wolf sheath (2), over which the hide was pulled; the sand pan (3), in which sand was heated to degrease the skins; the trampling barrel (4), in which the raw material is trodden as if in a fulling; the pedal stick (5), in which you
step “Rauchwerk” warm to get soft leather; the pickling barrel (6) for pickling sheepskins; the push-off iron (7); the combing board (8); the net hook (9) for packing the skins and some combs (10) with which sheep wool in particular was thinned.
  • The cutting machine removes heads, paws and other parts of the fur. It is also used to cut the skins that are not rounded.
  • The stretching machine is one of the oldest and simplest standard machines in the finishing shop . Originally it was used to elongate the skins that were manually spread out on the furrier's bench. It is also used to pull pet fur after tanning. The table stretching machine , the drawing machine and the continuous stretching machine work according to different systems .
  • The Bakel machine was first used in specialized sheepskin refiners . Bakeling (also known as bakering) is the work that the dresser performed by moving the fur in front of the medium-sharp and rough bench iron. With it he removed the so-called flywash adhering to the fur. While the Bakel machine originally served the same purpose, it was later used more and more for stretching mass-produced goods (“pile pelts”). Equipped with blunt knives, it can be used as a pure stretching machine.
  • With the wilting press , mainly large skins are dewatered (wilted) and at the same time stretched so that they are smooth and without creases ready for further processing. These are mainly sheepskins, calfskins and foalskins, as well as horse skins . Smaller skins are spun in pendulum centrifuges.
  • With the raw fur cutting machine , all skins delivered round are cut lengthwise on the belly side, except for the noble fur such as sable, mink , marten , possibly noble foxes and others. The furs are rounded and the type of slicing is left to the final processing furrier.
  • Grinding machines replace the manual activity of slitting , in which the bench dresser with the handy iron cut off or scraped off the loose leather parts with short movements with the hide. This made the skins very soft and white, which was mainly due to the chemicals used or the alum tanning. All skins that were trimmed round were processed in this way. Large companies used a grinding or dollier roller , which roughly corresponds to the later grinding machine. This type is mainly used in suede production, occasionally also for grinding calfskins and normal sheepskins. The end result is excellent leather softness with a padded feel. In modern tobacco goods refinement, the grinding spindle is used to process round skins, for example mink .
  • The drum grinding machine is used for thin cutting , leveling and cleaning of the leather side, mainly for nutria skins , muskrats , Persian and other lambskins.
  • Lubricating machines are used for skins that cannot be greased in the bathroom (leak greasing). In the past, the fat emulsion was applied with a brush in manual production, today this is only done on particularly valuable or sensitive types of fur with extremely fine hair in order to avoid sticking or matting during later processing. There are lubricating machines for brushing in and for applying (emulsion application machine).
  • The carding machine is used to comb out the skins on the hair side.
  • The finishing mark is applied to the hide leather with the stamping machine. Less in use since the rise of reversible furs.

See also

Commons : Fur dressers and refiners  - Collection of pictures, videos and audio files
Commons : Tools of the fur trimmers and fur refiners  - collection of pictures, videos and audio files

supporting documents

  1. Alexander Tuma: Pelz-Lexikon. Fur and Rough Goods, Volume XIX . Alexander Tuma, Vienna 1950, p. 129, keyword “lidern” .
  2. a b c d I. G. Farbenindustrie AG, Frankfurt am Main (ed.): Advice for the refinement of fur . Without date (between around 1950 and 1980).
  3. a b c d e f g h Badische Anilin- & Soda-Fabrik AG, Ludwigshafen am Rhein (Hrsg.): BASF advice for fur processing . Without date (approximately between 1955 and 1980).
  4. a b c d e f Herdt, Kniesche, Schubert: About the origin, dressing and coloring of tobacco products . Gerberschule Reutlingen (ed.), 1978, pp. 2, 7, 19 a.
  5. ^ A b c Christian Franke, Johanna Kroll: Jury Fränkel's Rauchwaren-Handbuch 1988/89 . 10. Revised and supplemented new edition. Rifra-Verlag, Murrhardt, pp. 371, 402, 397-404.
  6. Without author's name: Machines and apparatus for refining tobacco products . In the tobacco market. No. 1/2, January 2, 1942, Verlag Dr. Paul Schöps, Leipzig / Vienna, p. 7.
  7. a b c d Walter Pense: Rauchwaren . In: Handbuch der Gerbereichemie und Lederfabrikation , in the part: The types of leather and their production , the chapter: Smoking goods . 1955. Springer-Verlag, Vienna, pp. 547, 550, 552, 560.
  8. a b c d e f Friedrich Lorenz: Rauchwarenkunde. 4th edition. Volk und Wissen publishing house, Berlin 1958, DNB 453077579 , pp. 148-172.
  9. Kurt Nestler: The refinement of smoking goods . Deutscher Verlag, Leipzig 1925, DNB 361939485 , pp. 19-23.
  10. VEB paint factory Wolfen: Pelzfärberat . Wolfen Kreis Bitterfeld, revised and expanded edition, undated (IV / 10/36 Pd 164/60 800 Ag 04/5426/61/200 June 24, 1734), p. 12
  11. Explanation of technical terms. In: Das Pelzgewerbe No. 3 1964, Hermelin-Verlag Dr. Paul Schöps, Berlin et al. P. 132.
  12. ^ Francis Weiss : From Adam to Madam . From the original manuscript part 2 (of 2), (approx. 1980 / 1990s), in the manuscript p. 230. (English).
  13. Erika Rowald: The German tobacco product finishing a wage industry . Inaugural dissertation. Verlag Der Rauchwarenmarkt, Leipzig 1932, DNB 571116833 .
  14. ^ A b Anton Ginzel: 60 years of tobacco product refinement . In: The fur industry . Verlag Die Pelzwirtschaft, January 1, 1965, Berlin, pp. 44–55.
  15. ^ Jean Heinrich Heiderich: The Leipziger Kürschnergewerbe . Inaugural dissertation to obtain a doctorate from the high philosophical faculty of the Ruprecht-Karls-Universität zu Heidelberg, Heidelberg 1897, pp. 101-102.
  16. A. Ginzel: Prerequisite for good fur finishing . In: The fur trade. Vol. XVI / New Series, 1965, No. 3, p. 121.
  17. Paul Schöps among other things: Die Rauchwaren-Veredlungsindustrie . In: The fur trade. Volume XIV / New Series 1963, No. 1, p. 24.
  18. a b c d e f g Author collective: Tobacco manufacturing and fur clothing . Fachbuchverlag, Leipzig 1970, DNB 457885491 , pp. 501-521.
  19. a b Andreas Franke: Pro visone cutem (based on the HBC slogan “pro pelle cutem” (“I give my skin for fur”)) or A fur makes you inventive . In: The fur industry . Verlag Die Pelzwirtschaft, December 1969, Berlin, pp. 46–50.