Development of natural colours in Cr-Fe tanned garment leathers

摘要

Dyes based on synthetic formulations are widely used in the leather industry, however, many aryl amine dyes are restricted due to their carcinogenic nature. Environmental cooncern leads one to look for the dye products based on natural resources, which may have advantages of biodegradability and lower toxicity. We aimed to create an eco-friendly dyeing process by forming in-situ complexes between vegetable tannins and the Cr-Fe tanning salt, where the use of iron salts results in various colours on reaction with various vegetable tannins.