| 摘要 |
<p>PROBLEM TO BE SOLVED: To prevent a conductor pattern which is arranged on the printed wiring board from being damaged owing to a heat shock even when boring is performed by irradiation with laser light, etc. SOLUTION: This printed wiring board has a laser light reflecting layer formed of copper-zinc alloy with a high reflection factor on the laser-light irradiated surface of its 2nd conductor pattern 4 and CO2 laser light 21 reaching the laser light reflecting layer 4b is sufficiently reflected. Further, the surface roughness of the laser light reflecting layer 4b is less than 7μm, so the irregular reflection of the CO2 laser light 21 is suppressed. Consequently, even when boring is performed by the irradiation with the CO2 laser light 21, the 2nd conductor pattern 4 is prevented from being damaged on the whole owing to a heat shock.</p> |
