An adhesive contains: (A) a monofunctional epoxy compound having one epoxy group per molecule; (B) a polyfunctional epoxy compound having two or more epoxy groups per molecule; (C) a photo cation generator; (D) an acrylic compound; (E) a photo-radical generator; and at least one compound selected from the group consisting of (F) a monofunctional oxetane compound and (H) a polyfunctional oxetane compound.