To obtain a resin compsn. which is excellent in water resistance, resistance to emulsification in dampening water, and cleanability and also in capability of wetting a pigment and adhesion to a substrate and is suitable esp. for lithographic ink by incorporating a specific (meth)acrylate and a photopolymn. initiator into the same.

This resin compsn. contains a (meth)acrylic ester of trimethylolotane (e.g. trimethyloloctane triacrylate) pref. in an amt. of 5-95 pts.wt., a photopolymn. initiator (e.g. benzophenone and isoamyl p- dimethylaminobenzoate) pref. in an amt. of 0.5-40 pts.wt., and optionally an unsatd. compd. (e.g. ditrimethylolpropane tetraacrylate) pref. in an amt. of 0-90 pts.wt.