| abstract |
The present invention provides a photopolymerizable composition useful as a liquid photoimageable solder mask comprising (a) a reaction product obtained by reacting epoxy resin A containing at least two terminated epoxy groups with 0.8 to 1.2 mol, per 1 epoxy equivalent of epoxy resin A, of an α,β-unsaturated carboxylic acid and then reacting same with 0.2 to 1.0 mol, per 1 epoxy equivalent of epoxy resin A, of polybasic acid anhydride, (b) diluent, (c) sensitizer, (d) epoxy resin B consisting of tris (2,3-epoxypropyl) isocyanurate whose melting point is 130° C. or less, and (e) an epoxy resin curing agent represented by the general formula [I:] ##STR1## wherein R is --H, halogen, --NH 2 , --SH, aromatic hydrocarbon, a C 1 -C 4 alkyl group or NHR' (R' is a C 1 -C 4 alkyl group having --CN or NH 2 C═NH). |