For the purpose of mask-less manufacturing for Printed Circuit Board (PCB), a new process using electrophotography technology, principle of copy machines, has been proposed and evaluated. Wiring patterns can be formed by electroless plating on the seeding patterns printed with the novel toner that is made of thermosetting resin and metal fine particles. Insulating layer can be also patterned by printing with resin toner. To build up multi-layered structure of PCB, these two processes are repeated in turns. This new method has some big potential to simplify manufacturing process for wiring and reduce the cost of PCB. The first technical issues were to control electrostatic charge of toner including metal particles and to get enough quality of printed seeding patterns for electroless plating. We started to develop the novel toner from investigating about the relationship between metal contents, electrostatic charge of toner, and plating ability. And it was established that new wiring process using electrophotography is available for PCB tracing. Similarly, insulating single slayer and multi-layered structure were formed by new process and appraised. Additionally, some trial samples by this new process were evaluated by some basic reliability tests. For demonstration, flip chip assembly was carried out and antenna substrates for RFID tags were fabricated.
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