NOVELTY - A urethane resin having (meth)acryloyl group is obtained by reacting diol component (A) which does not have (meth)acryloyl group and comprising diol component (a) having carbonate structure and alicyclic structure in a molecule, diol (b) having carbonate structure and which does not have alicyclic structure and/or diol (c) having alicyclic structure and which does not have carbonate structure, polyol component having (meth)acryloyl group and two or more hydroxyl groups in a molecule and polyisocyanate component.    USE - Urethane resin is used for active-energy-ray-curable adhesive agent for back-surface protection sheet used for solar cell (all claimed), interlayer insulation film for multilayer printed wiring board and soldering resist for flexible printed wiring board. Can also be used in adhesive agent, ink and coating material.    ADVANTAGE - The active-energy-ray-curable adhesive agent containing the urethane resin and having excellent adhesiveness and heat-and-moisture resistance is economically manufactured, with high yield. The back-surface protection sheet containing the urethane resin having suppressed delamination by bubble generation.    DETAILED DESCRIPTION - A urethane resin having (meth)acryloyl group is obtained by reacting diol component (A) which does not have (meth)acryloyl group and comprising diol component (a) having carbonate structure and alicyclic structure in a molecule, diol (b) having carbonate structure and which does not have alicyclic structure and/or diol (c) having alicyclic structure and which does not have carbonate structure, optional diol component (B') which does not have (meth)acryloyl group, carbonate structure and alicyclic structure, polyol component having (meth)acryloyl group and two or more hydroxyl groups in a molecule and polyisocyanate component. INDEPENDENT CLAIMS are included for the following:    (1) active-energy-ray-curable adhesive agent, which contains urethane resin and an epoxy resin; and    (2) back-surface protection sheet of solar cell, which is obtained by laminating sheet-like materials through active-energy-ray-hardenable adhesive layer containing active-energy-ray-curable adhesive agent.