Preparation method of electrolytic copper foil surface treating agent

The invention belongs to the technical field of copper foil surface treatment, and particularly relates to a preparation method of an electrolytic copper foil surface treating agent. The preparation method comprises steps as follows: deionized water, gamma-(2,3-epoxypropoxy)propyltrimethoxysilane and gamma-aminopropyltriethoxysilane are mixed at the volume ratio of 1:1:1 at the reaction temperature of 5-35 DEG C; and a catalyst is added into the mixed liquid in the stirring process and continuously stirred untill the solution is clear, and the surface treating agent is obtained. The surface treating agent adopts a composite silane coupling agent solution, and the rough surface (M) of an electrolytic copper foil is coated with the surface treating agent. Compared with single use of a silane coupling agent KH-560 or KH-550, the composite silane coupling agent can effectively enhance the binding force of the copper foil and a high-Tg board and particularly can effectively prevent the reduction problem of binding force of the copper foil and the board due to boiling property and soldering resistance.