Diethyl phthalate solution is widely used as a plasticizer in the production of flexible plastics, particularly in the manufacturing of items like vinyl flooring, adhesives, and synthetic rubbers. It helps improve the flexibility, durability, and workability of these materials. Additionally, it serves as a solvent in various industrial applications, including cosmetics and personal care products, where it helps stabilize fragrances and maintain product consistency. In the pharmaceutical industry, it is utilized as a coating agent for tablets and capsules to control their release properties. Its low volatility and compatibility with a range of substances make it a versatile component in diverse formulations.