Optical Brightener is colorless additives used in plastic pigments to improve the appearance of the final product. It absorbs invisible ultraviolet light and re-emits it as visible blue light, enhancing the whiteness and brightness of the plastic. It is typically in a powdered physical state, and it is commonly used in products such as laundry detergents, paper, and plastics. This Optical Brightener allows for easy incorporation into plastic pigments, resulting in a final product with enhanced color vibrancy and visual appeal.