PTH
PTH (Plating Through Hole) process is to deposit an uniform and very thin copper in through holes, which provides the best conductivity for following copper plating
QHC-408
Jiangnan Fine Chemical's
QHC-408 is high stable and room temperature operated electroless copper additives, it is suitable for both flash copper plating and panel plating. This process can deposit a dense and uniform copper layer in the hole walls, which presents bright pink color. After QHC-408 process, the defects of electroless copper can be inspected easily and further eliminate void and skip plating in the hole. QHD-408 process has wide operation window and longer bath life.
QHC-408工艺process has an unique conditioner, which can fully activate FR-4 materials, high-Tg materials, halogen free materials and polyimide materials. It helps to deposit uniform copper layer in the hole wall without Plasma treatment and can effective reduce the running cost, and also this special conditioner is suitable for both flexible and rigid PCB electroless copper process..
Process flows 
