| 摘要 |
<p>The present invention is (1) a glass cloth composed of a group of warp yarns and a group of weft yarns wherein one of the group of the warp and weft yarns are arranged with substantially no gap between the yarns, and, in that group, a width A ( mu m) of a cross-section of the yarn arranged with substantially no gap, a single-fiber diameter L ( mu m) of the yarn, the number N of single-fibers constituting the yarn and a weaving density C (ends/25 mm) of the glass cloth composed of the yarns satisfy the following equation (1-a) : <DF NUM="(1-a),">C xA / (25 xL xN) >/= 1.0 </DF> and (2) a glass cloth composed of a group of warp yarns and a group of weft yarns wherein both of the groups of the warp and weft yarns are arranged with substantially no gap between the yarns, and, in both the groups, a width A ( mu m) of a cross-section of the yarn, a single-fiber diameter L ( mu m) of the yarn, the number N of single-fibers constituting the yarn and a weaving density C (ends/25 mm) of the glass cloth satisfy the following equation (1-b): <DF NUM="(1-b).">C xA / (25 xL xN) >/= 0.75 </DF> The glass cloth according to the present invention is useful as a substrate for a printed wiring board. The printed wiring board using the glass cloth of the present invention as a substrate is capable of being bored with a laser beam to produce micro-holes (the roughness of the inner wall, the reproducibility and the roundness of the micro-holes are improved) therein, especially, is able to prepare uniform and small via-holes which are recently required for high-density wiring. <IMAGE></p> |
