Accordingly, copper alloy will produce chemical reaction with acid, akali, oxidizer, reducing agent and vulcanized agent, and then form into different color salt. If these material are rich in chemical we mentioned above and keep in humid, high temperature environment, the metal part of zipper will lost its color, like chains, slider, top & bottom stop and opening part. For example, if the product packed immediately or kept in polythene bags for a long time after ironing in sewing processing, the color lost will probably be occurred, especially the colorful cloth. And the copper alloy will lose its color and remain spot for the dye cloth of sulfur.

Wool product
The color of metal part of zipper will be changed after bleach processing. Usually we use oxidizer(peroxide, etc) or reducing agent(sulfitation) as the bleaching of wool fabric, and some use oxychloride for shrinkproof process. If these wool fabric cannot be washed enough or neutralized completely, some gas will be engendered, like chlorine or sulfur oxide. The sulfitation or chlorinating agent will react with metal material in humid environment, for example, the color will be changed if packed instant and laid for a long time after ironing. Therefore, please washing enough and using the dry wool material. And the product should be packed in dry after ironing.

leather product
The color of metal part of zipper will be changed by the rest of tan detergent and acidity after tan process.
The main tan detergent is vitriol acid or other inorganic acid ,chrome compound, tannin and aldehyde compound, the main component of leather product is albumen, and it is difficult to clean these tan compound out and a great deal of chemical residue was remained. The color of zipper will be changed when the leather and the metal part of zipper touched for a long time ,especially the golden zipper and nickle brass zipper. Therefore, please use the leather after washing enough and neutralising after tan process. Before you sew the leather, please apart them in the air. And should be noted that the color alter pen and the glue in the zipper or the color of zipper will be changed.

Second, why does zipper lost its color after heavy wash or enzyme  wash?
all of the color of metal zipper will fade different according to washing intensity, temperature and time, because all the metal zipper, especially the dark nickel and dark anti-copper, react with strong acid, strong base in strength washing as well as friction with stone. We take some ways to protect the zipper, like high temperature against oxygenation, but we can't avoid this kind of phenomenon cause of the environment factors.
Therefore, we will remain the sample you approved after washing, and we guarantee the quality of the product accord with the sample.

Third, Color migration will be occurred when sewing the light wear and ram material with dark color zipper?
If you choose the plating zipper, like silver, dark anti-copper ,aluminum, etc. for ram or light wear or bag, the color migration will be occurred because the paraffin of zipper touch the cloth for a long time or ironing. So please use the paraffin paper or cloth to avoid color migration when ironing or packing.

Fourth, Why does the scroop break when use heavy wash and thick cloth?
Please do not use small size#3 zipper but big size#3 zipper when your esteemed company need heavy wash or thick cloth to avoid the zipper scroop break.

Fifth, Why does the color of painting slider fade when use industrial wash water?
The painting slider will lose its color when crash in industrial wash, thus, please make the slider to top stop and wrap with cloth to avoid damaging the slider and tearing the zipper under the washing processing.