Dimethicone

✦ Forms a breathable silicone barrier that locks in moisture without clogging pores
✦ Delivers an instant silky smooth feel to creams, serums, and lotions
✦ Conditions and detangles hair while adding shine without weighing it down
✦ Improves spreadability and slip of cosmetic formulations significantly
✦ Fills fine lines and wrinkles temporarily for a visually smoother appearance
✦ Non-comedogenic and suitable for sensitive and acne-prone skin types
✦ Synthetically derived silicone polymer that is chemically inert and hypoallergenic

Dimethicone is a linear polydimethylsiloxane polymer and one of the most widely used silicones in the cosmetics industry. It has been a staple in personal care formulations since the mid-20th century, valued for its unique combination of skin protection, hair conditioning, and formulation enhancement. Its chemical inertness and excellent safety profile have made it a go-to ingredient for global cosmetic manufacturers for decades.

What sets Dimethicone apart from traditional emollients is its ability to form a non-occlusive breathable film on the skin surface. Unlike heavy oils or waxes, this silicone barrier permits moisture vapor exchange while still reducing transepidermal water loss. This mechanism gives skin a smooth, non-greasy finish while protecting against environmental irritants, making it uniquely effective as both a skin protectant and a sensory modifier in formulations.

Rabibazaar supplies cosmetic-grade Dimethicone suitable for DIY beauty formulators, professional cosmetic chemists, skincare brand developers, and haircare product manufacturers.

INCI Name : Dimethicone
Chemical Name : Polydimethylsiloxane
CAS Number : 9006-65-9
Molecular Formula : (C2H6OSi)n
Appearance : Clear to slightly hazy colorless liquid (viscosity grade dependent)
Odor : Odorless
pH (1% solution) : Not Applicable (non-ionic, non-aqueous)
Solubility : Insoluble in water; soluble in silicone fluids, aromatic solvents
Specific Gravity : 0.96 to 0.98 (varies by viscosity grade)
Flash Point : Greater than 300°C (closed cup, high viscosity grades)
HLB Value : Not Applicable
Recommended Use Level : 1% to 5% in skincare; up to 10% in haircare
Type : Synthetic silicone polymer (emollient, skin protectant)
Shelf Life : 24 to 36 months when stored properly

Skincare (Creams, Serums, Lotions) ★★★★★
Dimethicone is one of the most effective sensory enhancers in skincare, delivering a smooth non-greasy finish. Use at 1% to 5% in the oil phase to improve spreadability and reduce tackiness in moisturizers and serums.

Haircare (Shampoo, Conditioner, Masks) ★★★★★
Excellent for adding slip, shine, and detangling properties to hair products. Incorporate at 2% to 5% in conditioners and leave-in treatments for best results.

Soap Making (Cold Process, Melt and Pour) ★★☆☆☆
Dimethicone has limited utility in soap making as saponification disrupts its film-forming ability. It can be added at low levels in melt and pour soap for a silky skin feel but offers minimal benefit in cold process formulations.

Body Care (Scrubs, Butters, Balms) ★★★★☆
Adds a silky barrier finish to body butters and balms without heaviness. Use at 2% to 4% to enhance skin feel and improve product glide in body care applications.

Functional Cosmetics (Primers, Foundations, Sunscreens) ★★★★★
Dimethicone is a foundation ingredient in cosmetic primers due to its pore-blurring and smoothing effect. Use at 3% to 10% to create a velvety base that helps makeup adhere evenly.

In my formulations, I rely on Dimethicone as a go-to sensory modifier whenever a product feels too tacky, too heavy, or too draggy on the skin. A small addition of 1% to 2% can transform an average cream into a product with a premium feel. The key is selecting the right viscosity grade for your application — low viscosity grades like 5 cSt work best in lightweight serums and sprays, while high viscosity grades like 350 cSt or 1000 cSt perform better in rich creams and primers where you need more cushion and film formation.

ADVANCED TIP: Blend Dimethicone at 3% with Cyclopentasiloxane at 5% in your oil phase to create a volatile and non-volatile silicone combination that gives an immediate dry-silk finish followed by long-lasting skin protection. Add during the cooling phase below 40°C to preserve the volatile component.

Normal Skin : ★★★★★ — Enhances skin texture and provides a smooth non-greasy protective layer.
Dry Skin : ★★★★★ — Locks in moisture by reducing transepidermal water loss without feeling heavy.
Oily Skin : ★★★★☆ — Non-comedogenic and lightweight, though high concentrations may feel too occlusive for very oily skin.
Combination : ★★★★☆ — Works well on dry areas without aggravating oily zones when used at moderate levels.
Sensitive Skin : ★★★★★ — Chemically inert and hypoallergenic, making it one of the safest choices for reactive skin.
Mature Skin : ★★★★★ — Temporarily fills fine lines and creates a smoother skin surface appearance.
Acne-Prone : ★★★★☆ — Generally non-comedogenic but patch testing is advised as some acne-prone individuals report sensitivity to silicones.

CONCEPT 1: Velvet Finish Hydrating Primer
Usage Level : 5%
Key Ingredients: Cyclopentasiloxane, Niacinamide, Hyaluronic Acid
Result : A lightweight pore-blurring primer that smooths skin texture and creates an ideal base for makeup application.

CONCEPT 2: Silk Repair Leave-In Hair Serum
Usage Level : 4%
Key Ingredients: Cyclomethicone, Argan Oil, Vitamin E
Result : A glossy non-greasy hair serum that tames frizz, adds shine, and protects hair from heat styling damage.

CONCEPT 3: Barrier Repair Night Cream
Usage Level : 3%
Key Ingredients: Shea Butter, Ceramide Complex, Squalane
Result : A rich yet non-greasy overnight moisturizer that strengthens the skin barrier and locks in active ingredients while you sleep.

INCI Declared : Yes — required when present in the formulation
EU Cosmetics Reg : Permitted — no concentration limit for cosmetic use
Rinse-Off Limit : No limit established
Leave-On Limit : No limit established
Allergen Alert : No — Dimethicone is not a recognized allergen
Skin Safety : Safe at recommended levels; extremely low irritation potential
Eye Area Use : Safe — widely used in eye creams and eye makeup products
Ingestion : Not for internal use
Pregnancy Use : Safe — no known concerns at cosmetic use levels
Child Safety : Safe for all ages at recommended cosmetic use levels
Ventilation : Not required
Storage : Cool dry place away from direct sunlight
Container : HDPE, PET, or glass — no special container restrictions

Working pH Range : Stable across pH 3 to 12 (chemically inert, pH independent)
Heat Stability : Stable up to 200°C; can be added to hot or cold phase
Freeze-Thaw Stable : Yes
Emulsion Type : O/W, W/O, Both
Emulsification Phase: Hot or Cold — compatible with either phase
Compatible With : Silicone emulsifiers, fatty alcohols, vegetable oils, waxes, most cosmetic actives
Incompatible With : Strong oxidizing agents; may destabilize some cationic surfactant systems at high concentrations
Oxidation Risk : Low — silicone backbone is highly resistant to oxidation
Discoloration Risk : None — chemically inert and colorless
Formulation Notes : High viscosity grades may require pre-blending with a low viscosity silicone or light carrier oil for easier incorporation into emulsions.

Q: What does Dimethicone actually do in skincare products?
A: Dimethicone forms a breathable protective layer on the skin that reduces moisture loss and smooths surface texture. It also improves the feel and spreadability of creams and lotions, giving them a silky non-greasy finish.

Q: Does Dimethicone clog pores or cause acne breakouts?
A: Dimethicone is classified as non-comedogenic and is generally safe for acne-prone skin. However, formulations with very high silicone concentrations combined with heavy oils may contribute to congestion in some individuals, so patch testing is recommended.

Q: What viscosity grade of Dimethicone should I use for my formulation?
A: Low viscosity grades (5 to 100 cSt) are ideal for serums, sprays, and lightweight products. Medium grades (200 to 500 cSt) work well in lotions and conditioners. High viscosity grades (1000 cSt and above) are best for primers, heavy creams, and barrier products.

Q: Can I use Dimethicone in natural or organic formulations?
A: No. Dimethicone is a synthetic silicone polymer and is not permitted in certified organic or natural cosmetics. For a natural alternative, consider plant-derived squalane or broccoli seed oil which offer similar smoothing effects.

Q: How does Dimethicone compare to Cyclomethicone?
A: Dimethicone is a non-volatile silicone that stays on the skin and provides lasting protection and smoothness. Cyclomethicone is volatile and evaporates after application, leaving a dry finish. Many formulators combine both for an immediate dry-silk feel with long-lasting conditioning benefits.

Product evaluation

Review the specifications, supplied grade, intended use and compatibility of Dimethicone before ordering for production. Test a small quantity in the actual application and document the result before scaling.

Quality control

Inspect the received batch for expected appearance, odor, texture, packaging condition and labeling. Keep supplier and batch records, use accurate measurements, and retain a reference sample when the material is used commercially.

Storage and responsible use

Store tightly closed in a clean, cool and dry location away from direct sunlight. Follow the current supplier instructions and all safety, labeling and regulatory requirements that apply to the intended finished product.