1. Impure Raw Materials
Raw materials used may contain impurities, causing the finished product to turn black.
2. Additive Problems
If some additives do not meet the requirements, they may react or decompose with the main ingredients to product black substances.
3. Overheating
During the production process, if the temperature is too high, some ingredients may thermally decompose or coke, resulting in black substances.
4. Uneven Stirring
If the mixing process is uneven, some ingredients may aggregate to form black particles or precipitation.
5. Storage Conditions
The product may be affected by light, temperature or air during storage, causing the material to deteriorate or oxidize.
6. Equipment Contamination
If the production equipment has been used with materials of other colors before, cross contamination may occur.