1. There is color difference around the blind hole in the seam of dyeing products.
Reason: The cleaning after oxidation is not thorough, and the sulfuric acid volume is slowly released outward during dyeing, which causes the PH of the local dyeing solution to change.
Treatment method: Strengthen the cleaning before dyeing, and can be cleaned separately with a fine water gun.
2. Can't dye.
There are many reasons for the failure of dyeing after oxidation, the biggest of which may be the absence of oxide film formation on the surface of the product.
Not enough oxidation time.
3. Color surface flower.
Hair flowers appear in a large area of products, there are several reasons:
① The pretreatment of the product is not clean, the original oxide film on the surface of the substrate is not removed, and it is difficult to produce an oxide film during oxidation, resulting in no color.
② The pre-treatment of the product is not carried out light treatment, or it is not oxidized for a long time
③ Dyeing temperature, low concentration.
④ There is oil on the surface of the dyeing tank. You can shake it a little bit more when dyeing
⑤ The oxide film of the reworked product is not returned clean
The oxide film is contaminated, the product should be kept clean before dyeing, and do not come into contact with other things.
⑦ Oxidation time, temperature, concentration from the normal process.