EXULTRA ACID COPPER PLATING PROCESS
1. Advantages
Excellent brightening and leveling ability
Great throwing power with good leveling in LCD area
No pitting deposit with good ductility and corrosion resistance
This process is very easy to control with stable bath, and lower maintaining cost
Suitable for all kinds of parts. especially for the plating of lamp decoration and plastic parts
Bath composition and working conditions
Bath composition & Technical Data |
|
| Usable Range |
| Standard | |
(CuSO4·5H2O) | 200 – 220 | (g/l) | 220 | (g/l) | ||
(H2SO4) | 55 | – 70 | (g/l) | 60 | (g/l) | |
(Cl - ) | 70 | – 120 | (mg/l) | 80 | (mg/l) | |
QRD – C | 6 – 8 |
| (ml/l) | 8 | (ml/l) | |
QRD – A | 0.4 | – | 0.6 | (ml/l) | 0.6 | (ml/l) |
QRD – B | 0.4 | – | 0.6 | (ml/l) | 0.4 | (ml/l) |
Temperature | 20 | – 35 ℃ |
| 24 – 28 ℃ | ||
CD in cathode | 1 – 6 | (A/dm2) | 3 – 5 (A/dm2) | |||
CD in anode | 0.5–2.5 (A/dm2) | 0.5–2.5 (A/dm2) | ||||
Anode | Copper anode（0.03-0.06%phosphorus） | Copper anode（0.03-0.06%phosphorus） | ||||
Voltage | 1.5 | – | 6 (V) | 1.5 – 6 (V) | ||
Agitation | Air agitation or mechanical agitation. | Air agitation | ||||
3． Make up the solution
nFill up with tape water in 50% of the volume of the plating tank, heat the water until to 40 - 50℃. (The chloride ion content in the used water should be lower than 70mg/L.) then add the required copper sulfate with stirring until completely dissolved;
nAdd 2.0g/L activate carbon, stir it for more than one hour, then filter it into the clean plating tank, add tape water until to the working water level.
n Slowly add the required sulfuric acid with strongly stirring to ensure keeping the temperature of the bath solution is less than 60℃.
nMake the temperature of the bath solution cool to 25 ℃, then add hydrochloride acid or sodium chloride according to the chloride ion content in the bath solution to ensure the chloride ion content can reach the standard value.
Finally add the required quantity of additives, electrolyze for about 2 hours with 0.5 A/dm2 current. After that, the solution is readying for using.
4． Equipments
nPlating tank： steel tank or plastic tank with liner PVC or other plastic
nCooling machine: If the temperature of the bath solution is too high, it will cost a large
consumption of brightener; meanwhile it will result in a poor brightness in LCD area. Therefore, it is necessary to use the right cooling machine.
nCycle filter： The seston such as dust and lipin in the solution will result in rough deposit, pitting deposit, low brightening. It should adopt cycle filter to filter the solution. The filter pump can filter the solution for 4 times in one hour at least.
nAir agitation： It should adopt enough strong air agitation to avoid pitting.
nCopper anode ： The phosphorus content should be in 0.03 ~ 0.06%; If the phosphorus
content is too low, it is easy to appear burr due to copper powder; If the phosphorus content is too high, it will result in too thick phosphorus films on the anode surface to cause pitting or pinhole on the deposit.
nAnode bag ： It should choose acidic & alkaline resistance polyester fiber bag with
double layer to avoid the anode dust gets into the solution.。
5． Functions and addition of the brighteners
QRD – C：QRD – C is not enough, the pitting will appear on the deposit, some loose striation deposit will appear on HCD or MCD area; EXULTRA – MU is excessive, it will appear fog deposit on LCD area.
QRD – A：When brightener EXULTRA – A is too low, the leveling will decrease on the plating layer; when brightener EXULTRA – A is excessive, the leveling on LCD area will decrease and form an obvious demarcation.
QRD – B When brightener EXULTRA – B is not enough, the deposit will easy to get burnt; When brightener EXULTRA– B is excessive，it will result in fog on LCD area.
6． Consumption：
QRD – C | ： | 30 – 80 ml/1000 A.H |
QRD – A | ： | 50 – 90 ml/1000 A.H |
QRD – B | ： | 30 – 80 ml/1000 A.H |
Note: The above consumption quantity is only for reference, actual consumption is different according to different work pieces and process.