Patent ID: 11877397

Abstract:
The printed circuit board includes, a first conductive layer including copper foil, an insulating base layer, and a second conductive layer including copper foil in this order, and includes a via-hole laminate that is stacked on an inner circumference and a bottom of a connection hole extending through the first conductive layer and the base layer in a thickness direction. The via-hole laminate has an electroless copper plating layer stacked on the connection hole and an electrolytic copper plating layer stacked on the electroless copper plating layer. The copper foil has copper crystal grains oriented in a (100) plane orientation, and an average crystal grain size of copper of 10 μm or more. The electroless copper plating layer includes palladium and tin, and an amount of the palladium stacked per unit area of a surface of the copper foil is 0.18 μg/cm2 or more and 0.40 μg/cm2 or less.