Leather Production - Production Chain

PRODUCTION CHAIN

The industry process chain may be split into 6 main production stages and the product at each stage has the potential to be traded internationally. The relative increase in added value and potential commercial profit can be seen as the raw material passes through the various stages of the chain.

1. Raw material

The raw material comes from cattle hides, and from the skins of other animals. It is biodegradable and loses structure and value if it is not preserved correctly and promptly after slaughter. This is normally by salting or drying. The hides and skins need to be without decay, cuts or damage, and of good shape.

In contrast to the well-developed quality and market standards in developed countries, this is critical factor in developing countries, which persist in primitive systems encouraging informal trade and preventing the full potential value being obtained.

A proposed African scheme is well designed but not implemented yet. ESALIA/CFC sorting standards classify ground, ball and smoked dried hides and skins as rejects; the lowest of 4 acceptable skin selections has defects up to 40% of skin area; above this 40% means that the skins are total rejects, together with untrimmed or poorly trimmed skins. Hides also have 4 grades, with the lowest grade having defects up to 50% of the hide area; above this 50% is a total rejects. "Fallen" hides and skins originate from animals dying naturally and are considered as reject material, unsuitable for processing. After soaking and hair removal in alkaline liming, they are pickled.

2. Pickle

The pickled state is a wet, acidic condition and a preparation for tanning the leather. "Pickled" leather is a traditional product, a commodity for export shipment of skins, which allows the importing tanner the widest choice in tanning materials. All other semi- processed materials have already been tanned and offer less flexibility regarding their potential final product.

3. Wet Blue & Wet White

Wet blue, and Wet White, comes from the tanned state. Tanning gives permanence to the protein and stops further decay. The "blue" refers to the more general chromium tannage, compared with the newer chrome- free white tannage. (Vegetable tannage is an older process, and still used for some upholstery, belts and sole leather. The natural colour of vegetable tannage is brown. It is not traded in the wet condition.)

"Wet blue" leather is well-established as a commodity for international trading, because of the widespread use of chrome tanning. As such it is price sensitive, provided quality and reliability is established. As stated above, this form of export is increasingly preferred by importers, because it arrives without risk of transmittable diseases, a factor of concern with unprocessed hides and skins. It also has the advantage that all processes, which cause the most damage to the environment, have already been carried out in the exporting country. A further advantage is that importers can specify the range of the quality selection they need to buy – which conversely means that the exporter has to consider the sale of the other grades.
"Wet white" leather is of increasing interest where chromium is to be avoided – for example, for automotive upholstery. These FOC (‘free of chrome’) leathers are expected to experience increasing demand in the future, as environmental concern and legislation grows.

After tanning, the wet hides and skins are usually dyed and further treated with softening chemicals. After drying, their condition is known as the "crust". This is the first point in the process at which they are actually dry.

4. Crust

Crust leather is dry and is easier to ship. It is also easier to see the quality of the surface appearance for grading and value judgements. It is ready for further processing, either for more wet work (retanning and dyeing), or for direct dry finishing.
It may be pure vegetable tanned crust, or a combination of chrome, synthetic and vegetable tannage. It is an advantage to develop such a product for a specific customer, who provides the guidance; otherwise it is much more difficult.

Properties such as tightness, softness and the response to finishing operations are critical in making a good product and demand greater technical ability.

Although some countries propose that exports should only be allowed as crust, or at an even later stage (in order to add value), the results have often been negative. The hides and skins from individual animals are different, and unique in their appearance, reflecting the animal's history. The classification of relative quality is the key operation in a tannery, and is carried out at several stages in the process.

The profitability of the whole business depends on using the grades for the appropriate products, and making an overall profit from all the raw material used. There should be no inventory without a potential sale"dead stock". After sorting for quality – surface appearance, feel, thickness – finishing coats of colour are applied, to improve the appearance and serviceability of the hides. These qualities are all customer-specific.

5. Finished leather

Finished leather has the potential to add even more value and to provide much better earnings, but it also is much more difficult to achieve successfully. Compared with wet blue leather, which can be made into a number of final products, finished leather has to be made in a specific type, colour and thickness for each specific product (and usually for each specific customer). There is no room for error to achieve a profit, and it is essential to develop finished leathers for each grade of crust material. The necessary semi-processed hides and skins (stages 2 to 4) are taken from the normal production line, according to the demands of the market. Specialist processing equipment is involved through all the stages.

6. Finished leather products

Finished leather products are made from the different leathers into a wide range of products. The major use of cattle hides is for the uppers of heavier leather shoes, but there are increasing demands for furniture and automotive upholstery. Skins are used for lighter shoes, leather clothing and gloves. Large and small leather goods, from suitcases and golf bags, to wallets and briefcases, are made from both hides and skins. Each finished leather product has its own specific leather requirements.

Contributed By Mr. Woodley, Michael International Consultant May, 2007
http://www.ab-corporategifts.com