| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a rolled copper foil in which when the foil is used as a wiring for printed wiring board even for long time using, any crack in the wiring is not developed; and a copper-clad laminate, flexible printed wiring board and electronic equipment, using the foil. <P>SOLUTION: When a portion having ≥2° of an azimuthal difference between the crystal orientation obtained by irradiating a measuring point of metallurgical structure of the crystal with an electron beam and the crystal orientation obtained by irradiating a plurality of adjacent measuring points positioned the electron beam by 0.5 μm separating distance around the measuring point, is determined as Σvalue in the crystal grain boundary as the crystal grain boundary; the rolled copper foil is the one that the total of the length of the crystal grain boundaries ≥Σ19 as measured after annealing at 400°C for one hour is 8 cm/mm<SP POS="POST">2</SP>or less. <P>COPYRIGHT: (C)2013,JPO&INPIT |
