(1) discoloration of chain teeth
Metal chains made of copper alloys (nickel, red copper, brass) are manufactured on wool products of metal products. Some teeth of zippers will be blackened due to metal oxidation, which is caused by the discoloration caused by the dissolution of incomplete residual gases in the products caused by ripening agents and bleaching agents.
Oxidation is the property of copper. In order to reduce the degree of change, zipper products should not be sealed in cellophane or heavy paper bags.
When metal chains are tied with rubber bands containing sulfides, the chain teeth will be vulcanized (blackened).
(2) Colour shift dyeing of cloth ribbon
Disperse dyes used in polyester ribbon dyeing may migrate with other products containing compounds. Therefore, although zippers are dyed with anti-migration formula, more attention should be paid to the use of dark zippers in white and plain fabrics.
(3) Dyeing often occurs when cloth (clothing) is in contact with the pull-link, and it also occurs due to temperature, air humidity, pressure, time of placement and other factors.
Please put a layer of paper between the products to prevent the phenomenon of migration and dyeing.