| 摘要 |
PURPOSE:To suppress the degree of warpage of a printed circuit board after a reflow to a reduced level by forming a row of slits, in which a plurality of fine slits arranged substantially orthogonal to a lengthwise direction of the board are drilled, at areas of the board to be disregarded which extend in the lengthwise direction of the board. CONSTITUTION:Perforations 2 are defined on the surface of a printed circuit board 1. A circuit board section 3 acting as an area where electronic components are mounted and areas 4 of the circuit board to be disregarded are adjacently formed with the perforations 2 between them. Fine slits 5 are formed at substantially right angles to a direction in which the circuit board 1 is transferred between various types of assembly units containing a reflow process during a process for mounting components on the board 1. A plurality of slits are also formed along a transfer direction 6. Warpage of the board 1 exists between the slits 5, but it appears outside as a considerably small amount of warp. The total amount of warpage arising over the entirety length of the board is suppressed to a value which satisfies the standard for printed circuit boards. |
