Propylene Glycol (PG), identified by CAS number 57-55-6, is a colorless, odorless, hygroscopic liquid with a slightly sweet taste, belonging to the diol family. As a multifunctional cosmetic raw material, it has been widely used in skincare, haircare, makeup, and personal care products for decades, valued for its excellent solubility, moisturizing properties, and formulation compatibility.

In cosmetic formulations, PG serves three core roles: first, as a humectant, it attracts and retains moisture from the air, forming a protective hydration layer on the skin’s surface to prevent dryness and maintain skin softness—making it a key ingredient in lotions, creams, and facial masks. Second, as a solvent and coupling agent, it dissolves both water-soluble and oil-soluble active ingredients (e.g., fragrances, preservatives, botanical extracts), ensuring uniform dispersion in formulations and enhancing product stability. Third, it acts as a viscosity regulator and freeze-thaw stabilizer, improving product texture and preventing separation or crystallization in extreme temperatures.

PG is non-irritating to most skin types (tested to be safe at concentrations up to 50% in cosmetics) and is compatible with other common ingredients like glycerin, hyaluronic acid, and surfactants. It is also recognized by regulatory bodies including the FDA (U.S.), EC (EU), and CFDA (China) as a safe cosmetic ingredient, complying with international standards such as the Cosmetic Regulation (EC) No 1223/2009.

Beyond basic applications, PG is used in hair care products (e.g., shampoos, conditioners) to reduce static and improve combability, and in makeup (e.g., foundations, lipsticks) to enhance spreadability and prevent drying. Its low toxicity and stable chemical properties make it a reliable choice for both mass-market and high-end cosmetic brands.

Storage recommendations: Store in a sealed container in a cool, dry place (15–25 °C), away from direct sunlight and heat sources. Shelf life is 24 months when stored properly.

Propylene Glycol (CAS 57-55-6) is a multifunctional, safe, and versatile cosmetic raw material with strong moisturizing, solubilizing, and stabilizing properties, compliant with global regulatory standards and compatible with most formulation ingredients.