The reactive resins of a sealant have a considerable effect on adhesive properties of liquid crystal devices (LCDs). In particular, the structure and composition of the resins greatly affect the adhesion strength, moisture permeability, and LC pollution of the sealant. Our study shows improvement in the adhesive strength and moisture permeability of UV/heat dual-curable sealant upon the introduction of a flexible di-functional acrylate resin. In this study, we have developed a new UV/heat dual-curable sealant containing a flexible acrylate resin instead of a conventional rigid acrylate resin to improve the adhesive strength, moisture permeability, and LC contamination.