Cu6A: Responsible for bright dipping and leveling. When the content of Cu6A is insufficient, bright dipping and leveling performance decrease, the area with low current density will not be bright; when the content of Cu6A is too high, the area with low current density becomes dark and the area with high current density is likely to be burned. In such case, the condition can be improved by adding Cu6B;
Cu6B: Commonly known as leveling agent. It is mainly responsible for leveling high current density area. When the content of Cu6B is insufficient, the high current density area is likely to be burned and the leveling performance decreases; when the content is high, mist is likely to appear. In such case, Cu6A can be added to improve the condition;
Cu6C: Commonly known as make-up. Its main role is to enhance the dispersibility. When the content is low, streaks are likely to appear on the coating. When the content is too high, mist is likely to appear.