Terephthalylidene Dicamphor Sulfonic Acid (TDSA) is currently one of the most effective chemical ingredients for filtering UVA rays. It absorbs high-energy UVA radiation, which poses significant harm to the skin, and also absorbs a portion of UVB radiation. It exhibits excellent photostability, does not decompose under light exposure, and maintains long-lasting efficacy. It is compatible with both oil-in-water and water-in-oil emulsion systems. Its typical usage rate in formulations ranges from 0.5% to 5%, with a maximum permitted concentration of 10% in China, the United States, Europe, and Japan. It blends seamlessly with water, resulting in formulations that feel non-greasy, lightweight, and refreshing on the skin. With a molecular weight of 562.69, it is not absorbed by the skin, posing no health risks. It demonstrates excellent tolerability, low allergenic potential, and is suitable for sensitive skin.

Chemical Properties

• Chemical Type: UV filter (UVA absorber)

• Solubility: Highly soluble in water (aqueous solution form); also compatible with various water-based cosmetic systems

• Appearance: Light-yellow transparent liquid

• Stability: Stable in cosmetic formulations; suitable for long-lasting sunscreen products

• Skin Feel: Lightweight, refreshing, and non-oily

Synthesis Methods

Typically synthesized by sulfonation of camphor-derived intermediates, followed by condensation with terephthalic derivatives, then processed into an aqueous solution for cosmetic use.

Functions and Usages

• UVA Protection: Effective UVA absorber, protecting skin from long-wave UVA damage

• Broad-Spectrum UV Filter: Helps prevent photoaging and pigmentation caused by UVA/UVB

• Formulation Advantages:

• Ideal for water-based sunscreens

• Supports transparent spray formulations

• Enhances lightweight texture and non-sticky feel

• Typical Usage Level: Commonly used in sunscreen products at levels that comply with regional regulatory limits (varies by country)