MASKING PRODUCT FOR A CHROMIUM-SULPHATE-BASED TANNING AGENT, AND METHOD OF TANNING SKINS IN AN AQUEOUS MEDIUM

摘要

Masking product for a chromium sulphate-based tanning agent ensuring the delayed association of chromium ions in solution to promote their absorption into the materials to be tanned. Said product comprises a mixture of alkaline formate and alkaline sulphite reacting synergically to ensure that the chromium sets almost completely and irreversibly on the skins. The invention is characterized by almost complete burnup of the tanning baths and a subsequent low salting out rate.