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The surface of the plate is white or uneven color copper acid plating tank itself may be the following aspects
30May
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The surface of the plate is white or uneven color copper acid plating tank itself may be the following aspects

Innovative from the fundamental improvement of technology level

ZS solution is to strengthen water washing, strengthen the schedule, strengthen acid oil removal strength. Copper acid plating tank itself, at this time its pre-treatment, generally will not cause the surface of the copper particle, because the non-conductiveparticles caused by the most plate plating or pits. The causes of copper particles on the surface of the copper cylinder can be summarized into several aspects: tank parameter maintenance, production operation, material and process maintenance. 


In terms of tank parameter maintenance, the content of sulfuric acid is too high, the content of copper is too low, and the temperature of the tank is too low or too high. Especially in the factory without temperature control cooling system, the current density of the tank will drop. According to normal production process operation, copper powder may be produced in the tank and mixed into the tank.

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In the production operation, the current is too large, the splint is bad, the empty pinch point, and the plate in the groove is dissolved by the anode. It will also cause the current of some plates to be too large, resulting in copper powder, falling into the groove, and gradually producing copper particle failure; In terms of materials, the main problems are the content of phosphorus and the uniformity of phosphorus distribution. Production and maintenance is mainly large processing, copper Angle is added into the slot, mainly in large processing, anode cleaning and anode bag cleaning, many factories are not handled well, there are some hidden dangers. The surface of the copper ball should be cleaned and the fresh copper surface should be eroded with hydrogen peroxide. The anode bag should be soaked with hydrogen peroxide sulfate and alkaline solution and cleaned, especially the anode bag should be cleaned with 5-10 micron gap PP filter bag.


Plating pitting is also a defect that causes many processes, from copper plating, graphic transfer, to pre-plating treatment, copper plating and tin plating. The main cause of copper sinking is that the copper sinking hanging basket is poorly cleaned for a long time. In the micro-corrosion, the polluted liquid containing palladium copper will drop from the hanging basket on the surface of the plate, forming pollution. After the copper plate sinking, the spot-like leakage plating is also called pits.


 Graphics transfer process is mainly caused by equipment maintenance and development cleaning poor, there are many reasons: brush roller suction stick pollution glue stains, blow-dry drying section of wind knife fan viscera, oil dust, etc., the surface of the board film or improper dust removal before printing, development machine development is not clean, poor washing after development, anti-foaming agent containing silicon surface pollution. Electroplating pretreatment, because whether it is acid degreasing agent, micro corrosion, preleaching, the main components of the tank are sulfuric acid, so the water hardness is higher, there will be turbidity, pollution board; Other parts of the company hanging glue is bad, long time will find the glue in the tank at night dissolution and diffusion, pollution tank; These non-conductive particles adsorbed on the surface of the plate may cause different degrees of plating pits for subsequent plating.


The surface of the plate is white or uneven color copper acid plating tank itself may be the following aspects: the air drum deviates from the original position, the air stirring is not uniform; Filter pump leakage or liquid inlet near the air blast pipe suction air, produce broken air bubble, adsorption on the surface or line, especially transverse line, line Angle; In addition, there may be another point that poor quality cotton core is used, which is not thoroughly treated. The anti-static treatment agent used in the manufacturing process of cotton core contaminates the tank liquid, resulting in plating leakage. In this case, air can be increased, and the liquid surface foam can be cleaned up in time. It is mainly a problem of polish or maintenance, and sometimes it may be a problem of acid cleaning after oil removal, micro-erosion. Copper cylinder polishing agent imbalance, serious organic pollution, tank temperature is too high may cause.


Acid oil removal generally will not have cleaning problems, but if the PH value of the water is acidic and more organic matter, especially recycling water, it may cause poor cleaning, uneven corrosion phenomenon; Micro-corrosion mainly consider the content of micro-corrosion agent is too low, the copper content of micro-corrosion liquid is high, and the temperature of the tank is low, which will also cause uneven micro-corrosion on the surface of the plate; In addition, the quality of the cleaning water is poor, the washing time is a little longer or the preleaching acid pollution, the surface may be slightly oxidized after treatment, in the copper tank electroplating, because it is acidic oxidation and the plate is charged into the tank, the oxide is difficult to remove, will also cause the uneven color of the board; In addition, plate contact with the anode bag, uneven anode conduction, anode passivation and other conditions will also cause such defects. Some common problems in acid copper plating process are summarized in this paper. 


At the same time, acidic copper plating process is widely used because of its simple solution basic composition, stable solution, high current efficiency, adding appropriate brightener can get high brightness, high leveling, high uniform plating ability coating. The choice and application of copper acid brightener is the key to the quality of acid copper plating. Therefore, it is hoped that the majority of staff can accumulate experience in daily work, not only to find solutions to problems, but also to innovate from the fundamental improvement of technology level.

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