| 摘要 |
PURPOSE:To reduce the residual of a resist in a through hole after development, by applying the resist having a prescribed low viscosity after coating a board with the resist having a desired high viscosity. CONSTITUTION:A through hole 3 is made in a copper-placed laminate (board) 1 and the whole surface of the copper-placed laminate 1 including the inside wall of the through hole 3 are plated with copper. After that, a circuit 2 consisting of a copper plated layer which is patterned with a tenting technique is formed. Then, this device requires to coat both faces of the copper-placed laminated 1 where the circuit 2 is formed with high viscosity resist ink 4. In such a case, it is preferable for the viscosity of resist ink 4 having a high viscosity to have 400poise or more and it is most desirable for ink to have 500-600poise. Subsequently, resist ink 6 having a low viscosity is applied to the surface of the copper-placed laminate 1. In such a case, it is preferable for the viscosity of resist ink 4 having a low viscosity to have 300poise of less and it is most desirable for ink to have 200poise or less. As to the run of resist ink 6 having the low viscosity into the through hole 3, the inside of the through hole 3 is veiled by resist ink 6 having the high viscosity and as a result, air pressure that is in existence in the through hole 3 prevents the run of resist ink. |
