CIRCUIT FORMATION METHOD OF PRINTED WIRING BOARD, THERMOSETTING RESIN COMPOSITION, AND PRINTED WIRING BOARD

摘要

PROBLEM TO BE SOLVED: To provide: a circuit formation method of a printed wiring board which allows formation of a fine circuit without need for a pretreatment plating step nor need for a step for polishing redundantly formed metals accompanying a plating film and a conductive coating film, and achieves good laser irradiation processability on an insulative resin layer, and good adhesion between the insulative resin layer and a circuit film; a thermosetting resin composition; and a printed wiring board.SOLUTION: The circuit formation method of a printed wiring board comprises: a reentrant structure formation step for irradiating, with an ultraviolet light laser of a nano-second-order pulse width, an ultraviolet light-absorbable insulative resin layer on a metal-clad laminate board, thereby removing the insulative resin layer and forming a reentrant structure; and a fluid dispersion coating step for coating the inside of the reentrant structure formed by the reentrant structure formation step with a fluid dispersion including metal nanoparticles according to an ink-jet method.