| abstract |
(57) [Summary] [Object] To provide a circuit board in which no solder balls remain when soldering to the solder resist film of the circuit board when, for example, a non-cleaning, low-residue type flux is used. [Structure] At least one of a carboxyl group and an onium group A photopolymerizable photosensitive resin having one, a photopolymerizable reactive diluent, a photopolymerization initiator, a thermosetting component, and an average particle size of 2 to 2 Photosensitive resin composition containing 0 μm inorganic powder Resin composition, cured coating film such as solder resist film, and circuit board using the same. [Effect] For example, the non-cleaning, low-residue type flux is applied to the solder resist film without any unevenness, and the application can be performed without unevenness of the solder and the solder balls can be soldered without remaining. In addition, the film improves various properties such as heat resistance and chemical resistance by adding a thermosetting component, and also has good developability by having a carboxyl group. When an onium group is contained, the film can be developed only by water. it can. And a circuit board with good reliability and productivity can be provided. |