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The base plate is the basic material for manufacturing PCB. Generally, the base plate is copper-clad laminate, and the single and double-sided printed boards are copper-2lad I. aminates，CCI。） On the other hand, selective hole processing, chemical copper plating, copper plating, etching and other processing are carried out to obtain the required circuit graphics. Another kind of multilayer printed boards is also based on the inner core thin copper-clad laminate. The conductive pattern layer and the prepr‘eg are alternately bonded by one-time lamination to form the interconnection between more than three conductive pattern layers. It has three functions of conduction, insulation and support. The performance, quality, processability in manufacturing, manufacturing cost and manufacturing level of PCB depend on the substrate material to a great extent. "

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