Sunlight is the ultimate source of the energy required for life on earth. However, the ultraviolet rays contained in sunlight causes color degradation and deterioration of the quality of plastics. Ultraviolet absorbers (UVA) absorb these detrimental ultraviolet rays, and prevent color degradation and deterioration of the quality of plastics. Benzotriazole type UVA absorb ultraviolet rays over a wide range of wavelengths. Johoku is currently engaged in the development of more highly functional UVA, with improved characteristics for industrial use.

 Hindered Amine Light Stabilizer (HALS) are another type of light stabilizer, which do not absorb ultraviolet but act as scavengers of detrimental free radicals generated by the energy in ultraviolet light. Due to their synergistic effects, combined use of HALS and UVA can result in better light stability as compared to use of either alone.