SURFACE-TREATED COPPER FOIL, AND LAMINATE, COPPER-CLAD LAMINATE, PRINTED-WIRING BOARD, AND ELECTRONIC APPARATUS USING THE SAME

摘要

PROBLEM TO BE SOLVED: To provide a surface-treated copper foil which can be well bonded to a resin, allowing the resin to have excellent transparency after removal of the copper foil by etching; and a copper-clad laminate, a printed-wiring board, and an electronic apparatus using the same.SOLUTION: A surface-treated copper foil has at least one surface having coarse-grained particles formed by roughening treatment. Two sheets of copper foil are attached to both surfaces of a polyimide resin substrate and then the sheets of copper foil on both surfaces are removed by etching. A printed matter with a linear mark laid under the exposed polyimide substrate is photographed with a ccd camera through the polyimide substrate. The lightness is measured for each observation spot of the image obtained through the photographing along a direction perpendicular to the extending direction of the observed linear mark, so that a graph of the observation spot-lightness is prepared. From the lightness curve extending from the end of the mark to the portion having no mark, the top average Bt and the bottom average Bb are obtained. The surface-treated copper foil has a difference &Dgr;B(&Dgr;B=Bt-Bb) of 40 or more.