In today's electronics industry is growing, with electronic products to the trend of light, thin, short, high-performance and multi-functional development and electronic devices welding technology, perfect, flexible circuit board (FPC) as the same for the electronic interconnect the circuit board has been in the past two years, the printed circuit board industry in China, the rapid development of increasingly wide range of electronic products for light, thin, short demand, flexible circuit boards, flexible printed circuit board and other type of printed board compared to a large number of wiring in a small space, require repeated bending parts due to the selection of a special material, so compared to other cable longer flex life.
Due to the characteristics of thin, flexible plate surface treatment in the process, the selection of the machine equipment and processing methods has its special requirements, the production of the flexible board, the surface cleaning treatment is a very critical one link, because it requires not only the surface of the good condition, there are also strict requirements for dimensional stability of the plate, and dimensional stability depending on the nip of the size of the rate of change of the copper foil layer has a great influence, but also the mechanical polishing in the production process, the abrasive brush the roller running direction, and the board conveying directioncontrary, is to ensure uniform grinding effect, but the flexible board substrate is thin and soft, the grinding pressure is too large substrate will be a great tension and are elongated or break, which is one of the important reasons for dimensional changes caused by the grinding process, should avoid substrate scratched, torn, and card board, if the device is not a professional the soft board production conditions, recommended pallet, this can be avoided due to the the machine driving wheel spacing, caused by high-pressure washing red rinse and drying hot air the substrate the card board deformed, or even scrapped.
Used in the flexible printed circuit board production process according to the requirements of the production process of the flexible board and the grinding brush wheel grinding chemical cleaning method and nylon needle brush roller is a pattern transfer hole metal and affixed cover film step surface treatment ideal choice for both able to clear the copper surface oxidation layer and can do a good plate surface roughness.
Chemical Shen gold surface pretreatment process, the selectable low cutting force non-woven brush roller, their uniform careful grinding effect can guarantee to remove the adhesive residue board pad meticulous uniform grinding processing, which is nylon pin brush to reach the effect of surface treatment, because the flexible plate is generally pads small and less ordinary nylon pin brush can not be completely ground to the pad, the strip will leave scratches and grinding, impact welding and surface appearance . Select a soft nylon pin brush cutting forces than conventional low non-woven brush roll can improve the effect can not be achieved, not woven brush roll their uniform careful grinding effect, is the first choice of many of the production of high-precision circuit boards manufacturers recommend the use of the brush roller surface The hardness of 30-45 degrees 1000 # +1200 # red non-woven brush roll for use with, the wear scar Control 8-10mm, ensure that the pad of dirt removal, the smoothness of the surface coating.
FPC in the holes prior to metallization required for cleaning of the surface polishing process to improve the binding force of the hole metal coating and substrate, while the hole after metallization copper surfaces prior to the pattern imaging effective treatment, the copper foil with the resist layer for enhanced the adhesion strength is very important, the FPC board holes prior to metallization Surface-untreated clean hole metallization layer may be layered, foaming phenomenon, the image before imaging cleaning the copper surface roughening is not enough, and the combination of the resist layer force is not enough, the production of fine line graphics prone diffusion coating, short circuit defects in the back of the plating process, causing the plates scrapped.
In the CCL surface grinding in front of the hole metallization and pattern transfer crude method, it is recommended to use 800 # +1200 # nylon pin containing alumina abrasive brush roll, not only can effectively remove the copper plating particles, and the copper surface coarsening effect, worn control 8-12mm, can effectively prevent the coil and grinding caused by excessive board be stretched, containing alumina abrasive nylon pin wire in processing copper surface, cutting efforts than traditional silicon carbide abrasive small, to reduce the plate surface scratches, scratches, the more dense and finer, the binding force of the plate surface with the resist layer, the better, in the back of the resist affixing, we recommend using wet foil, in order to more reinforcing plate surface the binding force with the resist layer.
Chemical cleaning method is the use of chemicals to remove the surface of organic debris and organic contaminants, and then micro etch solution to the surface roughening treatment, after treatment, the copper plate surface having a good flatness, but there is no mechanical scratches and residual abrasive particles, and therefore the fine conductor PCB processing relatively ideal clean roughened surface treatment method, but this method making clear the surface of the copper foil is not easy to completely on the copper particles and foreign matter leveling, easily oxidized, rough degree of mechanical polishing effect, suitable for the paste process before overlying cover film.
