What is the development history of ancient leather technology in China?

In the long years of ancient times, the progress of leather technology was very slow, and it remained in the production form of family manual workshops based on experience for a long time? And use oil for generations? Smoking? Bark? Alum? Tanning methods such as mirabilite?

The leather craft in Tying Wu Kai Naifu was written only by Glauber's salt? Tanning animal leather with sodium nitrate to soften it? The details of these processes are not recorded in ancient literature?

Ancient leather processing is a complicated chemical processing process with profound mechanism? For a long time, people only knew what it was and didn't know why. At that time, there was only the accumulation of processing experience, but there was no systematic mechanism? This is also the reason why ancient books are rarely recorded?