Did you know that metal zippers can change color when they come into contact with any chemicals remaining from a leather tanning process?
During the leather tanning process, tanning agents such as sulfuric acid, mineral acids, chrome compounds, tannic acid and aldehyde compounds are commonly used. When those tanning chemicals that are used on leather products come into contact with a metal zipper, the metal teeth may change color.
A color change can be accelerated if a metal zipper and a leather product are placed in an air-tight package or in a poorly ventilated environment, or if they are stored under pressure.
To prevent a metal zipper form changing color we advise using leather that has been washed sufficiently and neutralized after the tanning process. We also advise not storing a metal zipper with leather products in an air-tight package or in a poorly ventilated environment and avoiding letting the zipper have prolonged contact with a leather product or pressing a zipper against a leather product.
