| 摘要 |
PURPOSE:To prevent a reduction in the adhesiveness of a fine electric circuit by a method wherein a bonding agent layer is made to interpose between the electric circuit on an internal layer material and/or an external layer material and a prepreg. CONSTITUTION:A bonding agent is manufactured by a method wherein an epoxy resin (cresol novolak and/or bisphenol A), a phenolic resin (resol) and a butyral resin are respectively added to a solvent by 1/3 and the resins are dissolved in the solvent setting the amount of the resins at 15 to 25wt.% to the amount of the solvent. In the case of a coating of this bonding agent, a coating amount of 100 to 300g/cm<2> or thereabouts is effective. This bonding agent is applied between an electric circuit on an internal layer material and/or an external layer material and a prepreg, a prepreg is superposed on one surface or both surfaces of the internal layer material and moreover, an external layer material is superposed and the internal and external layer materials, the electric circuit, the prepregs and the bonding agent are integrally formed by a proper pressing and a proper temperature. According to this constitution, even if the width of the electric circuit is fine, there is no reduction in the adhesiveness of the electric circuit, a halo is hardly generated, a high-reliability multilayer board is obtained and as a polishing is not performed on the electric circuit, there is no damage to the electric circuit. |
