D5 silicone oil (decamethylcyclopentasiloxane) is a volatile cyclomethylsiloxane (cVMS) with the chemical formula C₁₀H₃₀O₅Si₅ and CAS number 541-02-6. Its colorless, transparent, odorless and low viscosity characteristics make it widely used in personal care and daily chemical products.


Technical parameters and functions
Physical properties: D5 has a viscosity of 3.9 mm²/s at 25°C, a relative density of 0.95, a flash point of 80°C (closed cup method), and a heavy metal content (in terms of lead) of less than 5 ppm, ensuring its stability and safety at high temperatures.


Functional advantages:


Spreadability and skin feel: Low surface tension allows it to quickly penetrate the skin, forming a smooth protective layer, improving wet combing and reducing hair tangling.


Carrier function: As an efficient solvent, it can carry active ingredients such as antioxidants to enhance the absorption effect of cosmetic formulas.


Safety: Passed multiple safety tests, non-irritating, non-comedogenic, suitable for sensitive skin.


Application areas
Personal care: As a core ingredient in antiperspirants (3-10%), hair care products (1-5%), skin care products (3-10%) and perfumes (0.5-3%), it provides a refreshing skin feel and long-lasting moisturizing.


Industrial use: As an intermediate for the synthesis of silicone oil, it is used in textile auxiliaries, defoamers and other fields.


Alternative solution research
Due to the EU's restrictions on D4/D5, researchers have explored alternatives such as isododecane and decamethyltetrasiloxane. Experiments show that the compound of decamethyltetrasiloxane and dodecamethylpentasiloxane (mass ratio 2:1) can combine the volatility of D5 with better spreadability, and the content of ring bodies is lower.