Pressure-sensitive adhesives (PSAs), which prevent an optical film being shrank under high temperature and high humidity conditions thus protecting light-leakage phenomenon resulting from the stress induced, were synthesized in this study. Such phenomenon occurs in the edge of an LCD panel because the stress is concentrated on its edge and distorts the absorbance axis of a polarizer. To enhance performance of the PSAs, spherical PMMA microbeads were synthesized and added into the acrylic-based polymeric PSAs in this study and then light-leakage properties of each PSAs with spherical microbeads were evaluated by the light-leakage pictures of the samples. Dynamic storage modulus (G') of the samples was also measured by a rotational rheometer and then correlated with light-leakage characteristics.