An ultraviolet curable resin composition is provided, which is excellent in developing
width and resolution, and exhibits good solder heat resistance and resistance to
gold plating. This resin composition comprises (A) an ultraviolet curable resin
obtained by reacting an epoxy-group containing polymer (a), which is prepared by
polymerizing an ethylenically unsaturated monomer component including an ethylenically
unsaturated monomer (i) having an epoxy group, with an ethylenically unsaturated
monomer (b) having a carboxyl group to obtain an intermediate product, and then
reacting the intermediate product with a saturated or unsaturated polybasic acid
anhydride (c); (B) an epoxy compound having at least two epoxy groups in its molecule;
(C) a photo-polymerization initiator; (D) a diluent; and (E) an ultraviolet curable
resin obtained by reacting a novolac epoxy compound (e) with the ethylenically
unsaturated monomer (b) having a carboxyl group, and then reacting a resultant
intermediate product with the saturated or unsaturated polybasic acid anhydride
(c). The ultraviolet curable resin (E) has an acid value of 10 mgKOH/g or more
and less than 45 mgKOH/g.