Tanning is the most important step in leather production because it preserves the animal skin and makes it stable and resistant. The tanning process prevents the protein threads from decomposing, sticking together and hardening when the animal skin dries. Only through several tanning steps does the raw hide of the animal become high-quality leather.
Most skins today are tanned cheaply with chromium salts in Asia and Latin America. The largest tanning centres are in Bangladesh, where workers, including children, often work unprotected in the toxic tanning broth and the waste water is discharged untreated into the river.
But chrome-tanned leather is not fundamentally toxic. It is only important that the tanner works cleanly. That is why we source our leather from a traditional German or British tannery that produces sustainably according to strict procedural requirements.
It is also possible to tan leather with plants, e.g. with tannins from bark, leaves, shells or roots. There is leather tanned with tannins from olive leaves, chestnuts or rhubarb root. Aldehyde tanning agents or synthetic tanning agents can also transform hides into durable leather. A process known as far back as 6000 years BC is seed tanning or tran tanning. Tran from cod, seal or whale, which have a particularly high proportion of unsaturated acids, is used for this. In the fibres of the leather, the fatty acids combine with the atmospheric oxygen. This oxidation-based tanning is also called fat tanning.