Ingredient · Linear Silicone
Dimethicone
INCI · Dimethicone
Related names and forms: Polydimethylsiloxane · PDMS. This list does not indicate synonyms or exact ingredient matches.
Dimethicone (INCI: Dimethicone; chemically polydimethylsiloxane, or PDMS) is the most widely used cosmetic silicone and the linear type generally meant by 'silicone'. It is a large polymer of repeating dimethylsiloxane units. Chain length, and therefore viscosity, varies with product needs, from thin fluids to highly viscous gel-like types. Its cosmetic role is largely superficial but versatile: a thin, smooth, slippery film on skin and hair provides a protective feel that softens dryness, creates a smooth makeup or primer base, and smooths hair to reduce visible frizz and support shine. Its light surface-coating, occlusive effect is also associated with slowing moisture evaporation. The common debate is that silicone clogs pores, suffocates skin or builds up. Dimethicone is a large molecule, does not meaningfully penetrate skin and is considered non-comedogenic in most assessments; a build-up feeling can be managed through regular cleansing. An important distinction: the silicones on the environmental agenda are cyclic types D4/D5/D6, not linear dimethicone. The EU is progressively restricting those for persistence and bioaccumulation. This does not mean dimethicone harms skin; the type and rationale differ. As a variable-chain-length polymer, dimethicone has no single small-molecule CID record; its reference framework uses general source families. Klaris considers type, dose, product and cleansing context, not a generalisation that silicone is bad.
i. Cosmetic Functions
Frequently Discussed Effects
The following headings summarise areas of effect frequently discussed in the literature; visible results in each area require regular use and a suitable formula.
Smooth Film and Slip
A thin film on skin and hair gives a smooth, slippery feel and a well-conditioned appearance.
Surface Moisture Retention (Occlusive Feel)
A lightly coating surface layer is associated with slowing moisture evaporation.
Hair Frizz and Shine
Smoothing the strand surface softens visible static and frizz and supports shine.
Mechanism
What Happens Within the Skin?
The following points summarise mechanisms from dermocosmetic literature in plain English. Klaris presents them as background information to help readers understand the context, not as medical claims.
Step 1
Large Linear Polymer (PDMS)
A large, inert molecule of repeating dimethylsiloxane units, with viscosity varying according to chain length.
Step 2
Surface Film
Leaves a thin, smooth, slippery film on skin and hair. Effects remain at the surface; meaningful skin penetration is not expected.
Step 3
Linear Is Not Cyclic
Different from cyclic silicones D4/D5/D6 on the environmental agenda; this distinction is decisive in skin and environmental assessment.
ii. Role in the Formula
How Is It Read on a Label?
Dimethicone is a large, inert linear polymer of dimethylsiloxane units, polydimethylsiloxane or PDMS, available at different viscosities according to chain length. Skincare widely uses it for a moisturising or protective feel, smooth texture and makeup or primer bases; hair care uses it for slip, frizz control and shine. Its large molecular structure does not penetrate skin meaningfully, so effects are largely superficial. It differs from cyclic silicones D4/D5/D6, a distinction important in both skin and environmental contexts.
Typical Concentration Range
1% - 15% (depending on product type and desired feel)
Ingredient Family
Conditioning Ingredients
iii. Sensitivity Advisory
A Note on Extra Care in Context
Most assessments consider dimethicone non-comedogenic and well tolerated; its large molecular size means skin penetration is not expected. A build-up feeling can be managed through regular, adequate cleansing. Layering a very heavy silicone routine on fine hair can feel weighty.
A sensitivity advisory is not an instruction for use; where individual health circumstances, pregnancy or known sensitivities are involved, discussing the decision with your doctor may be a more contextual approach.
Scientific Basis
Sources and Their Scope
The following headings indicate areas of research; they are not citations of a specific publication or confirmation that every statement on this page has been verified. The links provided should be read with their individual scope in mind.
- International INCI / CosIng database
- Formulation chemistry guides
- Cosmetic ingredient safety assessment groups
Starting Points for Independent Research
These links lead to official databases and serve as starting points for searches.
iv. Related Ingredients
Ingredients Often Read Together
v. Conditioning Ingredients Family
Other Ingredients in the Same Family
Explore ingredients in the same functional family to deepen your reading of formulas.
vi. Academy · Related Reading
For a Closer Look
6 Min Read
What You Need to Know About Silicones (Dimethicone)
Dimethicone's role in a formula, the pore-clogging myth and the environmental context of cyclic silicones.
5 Min Read
What Are Comedogenic Ingredients?
A measured explanation of the concept behind the risk of clogged pores.
6 Min Read
Curly Hair Care: How to Read the Ingredients
Curls change how moisture is distributed along the strand: humectant and emollient families, frizz tendencies and the context of washing.
Klaris · Example Analyses
How Does Dimethicone Feature
in Your Products?
Explore product examples to see the ingredient list, general assessment and match score that changes with the example profile together.
Masked products and example profiles, not a personal analysis. Profile matching in the app is part of Klaris Premium. The app is currently available in Turkish. An English version is in preparation.