关键词: 白湿革, 铬复鞣, 染色, 等电点

Abstract: Wet white leather tanned by TWLZ was rechromed by several chrome-containing retanning agents, respectively. The effect of rechroming method on the dyeing performance of wet white was investigated, and the possible causes of uneven dyeing were explored. The wet white without rechroming was used as control. The results showed that rechroming with chrome powder or chrome-containing syntan did not have any detrimental effects on dyeing levelness. Rechroming with chromium-zirconium-aluminum multi-metal retanning agent led to uneven dyeing performance. The metal distribution on the grain layer of the dyed leather retanned by the multi-metal retanning agent was relatively uniform, and the uptake rate of post-tanning chemicals was comparable to other groups. The main cause of uneven dyeing should be attributed to the fact that retanning by the multi-metal retanning agent increased the isoelectric point and the electropositivity of wet white leather, thereby resulting in the surface binding of dyestuff.

Key words: wet white, rechroming, dyeing, isoelectric point