ELECTRONIC CIRCUIT DEVICE, METHOD OF FORMING SEALING LAYER THEREOF, CIRCUIT BOARD AND DIE FOR FORMING THE SEALING LAYER

摘要

PROBLEM TO BE SOLVED: To form an integrated device with even a circuit board having mounted electronic components or attached connectors using a resin without burring, by covering approximately the entire board having the electronic components with a thermoplastic seal layer. SOLUTION: An electronic circuit device 10 has electronic components 12 mounted on a circuit board 11 approximately the entire of which is covered with a thermoplastic resin seal layer 13. The thermoplastic resin of this layer may be made of a polypropylene resin, polyethylene resin, polyolefin elastomer or other thermoplastic elastomer. The seal layer 13 contains uniformly dispersed foams to thereby cover and fix the entire circuit board 11 having the mounted components 12 with these layer 13, thereby providing characteristics of a superior water proof, moisture resistance and corrosion resistance and making easy to handle.