THROUGH-HOLE PLATING METHOD OF PRINTED WIRING BOARD

PURPOSE:To prevent such a trouble that plating is not deposited on the wall face of a through-hole from occurring by a method wherein the speed and the stroke of a plated object are specified, and a control scope of points required for the wettability of treatment solution to the plated object is cleared. CONSTITUTION:Provided that rho denotes the density (kg/m ) of treatment solution, CD is drag coefficient, V represents the oscillation speed (m/s), theta is a contact angle (degree) of treatment solution with the plated object, R denotes the diameter of a through-hole, and gamma represents a surface tension (N/m). A condition under which air bubbles are removed from a through-hole and treatment solution flows into it is given by a formula, V>(4 X gamma X (1-cos theta) mu CD Xrho X R). In the formula concerned, gamma, theta, CD, rho, and R are all measurable physical quantities, so that these are measured, whereby the range of a vibration speed of the plated object can be obtained from the formula. The amplitude of oscillation is set larger than the length of the through-hole of the plated object in an oscillation direction. By this setup, such a trouble that plating is not deposited in a through-hole can be prevented.