| 摘要 |
PROBLEM TO BE SOLVED: To provide a thermosetting resin composition which has, as a composition for solder resists, excellence in both concealment and characteristics suitable for laser processing; and to provide a dry film and a printed wiring board which use the same.SOLUTION: The thermosetting resin composition includes (A) an epoxy resin, (B) a colorant and (C) a hardening agent. (B) The colorant has an absorbance peak at least either at a wavelength of 350-550 nm or at a wavelength of 570-700 nm, and has absorption at a laser oscillation wavelength used in laser processing. |
