Multilayer board and electronic device

An electronic device comprising:

• a multilayer board;
• and
• another board;
• wherein
• the multilayer board includes:
• a first base material substrate including a plurality of insulating base material layers that are laminated and include a resin as a main material, the first base material substrate including a first region and a second region that includes a smaller number of the plurality of insulating base material layers than the first region;
• a second base material substrate laminated on the first base material substrate to straddle a stepped portion provided at a boundary between the first region and the second region due to a difference in the number of the plurality of insulating base material layers;
• a third base material substrate laminated on the second base material;
• a thick portion provided due to the stepped portion;
• and
• a thin portion provided due to the stepped portion, the thin portion having a smaller thickness than the thick portion in a lamination direction of the plurality of insulating base material layers;
• the thin portion is flexible;
• the first base material substrate includes a first conductor pattern provided on a surface in contact with the second base material substrate in the first region, and a second conductor pattern provided on a surface in contact with the second base material substrate in the second region;
• the third base material substrate includes a third conductor pattern and a fourth conductor pattern;
• the second base material substrate includes a first interlayer connection conductor that connects the first conductor pattern and the third conductor pattern, and a second interlayer connection conductor that connects the second conductor pattern and the fourth conductor pattern, and has a higher flowability than the first base material substrate and the third base material substrate when the first base material substrate, the second base material substrate, and the third base material substrate are laminated;
• and
• the multilayer board is, with the thin portion bent, connected to the another board.