Neutralising
From www.leather-dictionary.com - The Leather Dictionary
When neutralizing, the acid, which has penetrated into the leather during tanning, is removed again. Alkaline sodium carbonate is used in a concentration of 1.2%. Neutralizing is necessary, to allow the later fat-liquoring. A neutral pH value in the leather of 7 is not attempted, since this would dissolve the binding of the tannins to the skin-fibres and thus drastically reduce the durability of the leather. In practice, a pH value of 4-6 is desired.
Video about the leather production
The leather production in a modern tannery.
Process steps in the leather production |
---|
storage - soaking - liming - fleshing - splitting - pickling - tanning - neutralising - withering - sorting - shaving - yeing (through colouring) and fatliquoring - drying - finish - softening - final check |
Tanning methods |
---|
Chrome tanning - Vegetable-tanned leather - Synthetic tanning - Tanning with fats and oils |