people working at a leather tannery

Leather Terminology / Leather Tanning


Definition of Tanning

Tanning is the first step in leather production. It’s the process by which raw animal hides and skins are transformed into leather once they’re released from the beam house and cleaned from salt, dirt, blood, and hair.

The main purpose of tanning is to produce a sturdy and non-decomposable material from rawhide. Untanned hides will rot once they get wet.

Tanning essentially transforms the raw hide’s protein into a durable and usable material. The following are the key steps to leather tanning, depending on the leather type and its intended use:

  1. Soaking: Done to remove excess dirt or salt. In this step, every non-leather making component is removed from the hide in preparation for the next step, which requires clean and flat skins.
  2. Liming: Done to split the fiber bundles and remove unwanted hair from the hide by introducing alkaline. From here, the skin is referred to as a pelt.
  3. De-liming: After fleshing or splitting the pelt, de-liming is done to completely remove lime and minimize its neutralization effects. De-liming is usually done with organic acids or acid salts that form highly soluble lime complexes.
  4. Bating: It’s done to treat pelts with enzymes to soften them while maintaining their firmness and flexibility.
  5. Pickling: It involves adding acids to slacken the pelt and enhance the penetration of the tanning agents.
  6. Tanning: A tanning agent is used to alter the pelt’s collagen structure and convert it into a leather intermediate. It’s now a durable material protected against decay, chemicals, and microorganisms.

Example of Tanning in a Sentence

"Tanning leather is one of the most crucial steps in leather production."

Related Terms for Tanning

Written by Ryan Popoff

Ryan Popoff is the creative mind behind Popov Leather wallets, iPhone cases, belts, watch bands and journals since 2013. With a Bachelor Degree in Fine Arts, my leatherworking journey began at home. I wanted to create a simple leather wallet that could fit into my front pocket and — to my delight — it was a hit with family and friends. Hopefully you love our honest, quality leather goods too! Read more