Silicon Materials in Personal Care
title: "Silicon Materials in Personal Care" description: "Cyclomethicone, dimethicone, and amodimethicone in shampoo, conditioners, skincare, and colour cosmetics — the role of silicone oil in personal care formulation." section: "downstream"
Silicones as Beauty Ingredients
Silicones are the personal care industry's most versatile functional ingredient class. Their unique combination of low surface energy, non-greasy skin feel, chemical inertness, and wide viscosity range gives formulators tools unavailable from any other material family.
Global personal care silicone volume is approximately 180,000–220,000 tonnes/year, concentrated in hair care (60%) and skin care (25%).
Key Silicone Ingredients by Application
| Silicone type | INCI name | Application | Key benefit |
|---|---|---|---|
| Cyclopentasiloxane (D5) | Cyclopentasiloxane | Hair serum, dry oil | Evaporates, no residue |
| Cyclotetrasiloxane (D4) | Cyclotetrasiloxane | Carrier fluid (restricted EU) | Fast dry |
| Dimethicone 350 cSt | Dimethicone | Conditioner, skin cream | Smoothness, moisture barrier |
| Amodimethicone | Amodimethicone | Rinse-out conditioner | Hair shine, detangling |
| Phenyl trimethicone | Phenyl trimethicone | Shine serum | Refractive index, high shine |
| Dimethiconol | Dimethiconol | Hairspray, styling | Film formation |
Hair Care: The Largest Segment
Rinse-out conditioners use amodimethicone emulsions (1–3%) alongside quaternary ammonium conditioning agents. The amino groups deposit selectively on damaged hair (high cationic charge density at oxidised cuticle sites), building a protective silicone film that improves wet combing, reduces breakage, and enhances shine.
Silicone oil raw materials — typically amino-functional PDMS fluids — are emulsified with nonionic and cationic surfactants by high-shear homogenisation before compounding into conditioner formulations.
EU D4/D5 Restrictions
The EU restricted D4 and D5 in wash-off cosmetics (effective January 2020 and 2020 respectively) due to persistence and bioaccumulation concerns. Formulators have shifted to higher-molecular-weight polydimethylsiloxane (PDMS, non-cyclic), dimethiconol, and non-silicone alternatives. The restriction does not apply to leave-on products, where D5 remains in use.