What is vegetable tanning ?

Vegetable tanning, often known as E.I. Tanning (East India Tanning), is a historic and traditional method of tanning leather that have been passed down through generations. This is thought to be the world’s oldest leather-making tradition, using a procedure that has been honed through centuries, a method that is both environmentally friendly (using only organic tannins) and also more durable than synthetically processed leather.

 

Leather that has been vegetable tanned is believed to be of superior quality and will last longer than leather that has been synthetically treated. Vegetable-tanned leather takes at least thirty times longer to produce, which is one of the reasons why it only accounts for about 10% of all leather available today and can also cost up to three times more

History of Tanning

 

Vegetable tanning is said to have started around 6000 BCE, when humans in early civilizations were looking for a technique to render animal hides weather and decay resistant. Natural tanning agents from tree bark were used to tan leather. These tannins naturally bond to the collagen proteins in a hide, transforming it into the leather we know and love.

It used to be the only method to create leather, but recently, chrome or mineral tanning, a leather-making process that uses synthetic tannins, accounts for 90% of all leather processing method. Consumers may believe that this softer leather is of higher quality, but it will not last as long.

Advantages of Vegetable Tanning 

 

 

  • Vegetable tanning is environmentally friendly unlike synthetic tanning.
  • Vegetable tanning is an age old tradition, so most tanneries have very skilled artisans producing and dyeing the leather.
  • Due to the natural tannins used, vegetable tanned products are unique and have their own life, they are not the same for their entire life, but change continuously and develop a unique patina over time.
  • The colours that vegetable tanning produces are rich and warm tones that look completely natural.

VEGETABLE TANNING PROCESS

1. Soaking

Raw hides soak in water for 24 hours to remove the salt that kept them preserved on their journey

2. Liming, dehairing and scuding

A process that prepares the skins to receive the tanning substances

3. Re-liming

Hides are soaked in an alkali solution

4. Fleshing

Connective tissue and meat residue are removed from the flesh side of the skin

5. Deliming and Bating

The deliming step is carried out to reduce the excess of liming agents used in the previous unhairing operation. In the bating operation, skins are treated with proteolytic enzymes to open the fibrous structure of skins, increasing their softness.

6. Washing

Hides are washed after deliming and bating

7. Pickling

This process makes the fibres of the hides more receptive to tanning.

8. Vegetable Tanning

Either in pits or drum using vegetable tannins extracted from wattle bark (Acacia), Chestnut Wood (Castanea Sativa), Quebracho Wood (Schinopsis lorentzil), Avaram Bark (SennaAuriculata ), Konnam Bark (Cassia Fistula)

9. Intermediary Setting

10. Adding myrobalam plum

11. Oiling

12. Setting, drying, buffing, and trimming