Surface treatment for copper foil

摘要

The present invention provides a surface treatment agent that endows a copper foil with excellent adhesion to insulating resins. The surface treatment agent of the present invention has as its active components an organosilicic compound expressed by a following General Formula (1) and/or an organosilicic compound expressed by a General Formula (2) and an olefin-based silane coupling agent. The surface treatment agent of the present invention provides particularly excellent adhesion between an insulating resin and a low-profile copper foil used for a high-frequency-adaptable substrate. In Formulas (1) and (2), R<1 >is a hydroxyl group or a C1 to C5 alkyl group, and R<2 >is a C1 to C10 alkylene group that may contain oxygen.