Common Name(s): Trimethylsilyloxy phenyl silicone,cosmetic grade phenyl silicone

CAS Number: 2116-84-9

DESCRIPTION

What It Does: Provides superior shine and optical brightening from high-refractive-index phenyl silicone.

Why It's Used: Premium silicone for maximum shine applications in hair and skin products where pdms refractive index is insufficient.

How It Works: Phenyl groups increase refractive index from 1.40 (pdms) to 1.46-1.53 (phenyl silicone). higher ri closer to hair cortex ri (1.56) improves light reflection from hair surface for superior shine. better solubility for organic actives than pdms.

Typically Found In: Hair shine serums,high-gloss formulas,luxury silicone products

TECHNICAL DETAILS

Primary Category: Functional ingredient – phenyl silicone

Secondary Functions: Barrier sealing,softening

Application Areas:

Typical Concentration Range: 0.5%–15%

SOURCING & ETHICS

Vegan Status: Conditional - supplier confirmation required

Halal Status: Unverified - supplier confirmation required

Source Notes: Plant-derived, synthetic or animal-derived. verify source. [audit 2026-07-29 rev2: the record's own source_notes does not assert a non-animal origin, or instructs the reader to verify with the supplier; "yes" asserts knowledge the record does not hold. determination requires shariah-panel sign-off.]

SKIN COMPATIBILITY

Irritancy Rating: 1/5 – very low

Comedogenicity Rating: 1/5 – low; formulation-dependent

Sensitivity Concerns: Non-irritating.

Safe for Sensitive Skin: Yes

SAFETY & COMPATIBILITY

Safety Profile: Excellent safety profile. ewg score: 1.

Works Well With: Humectants,ceramides,actives as carrier

Avoid Combining With: No significant incompatibilities

SCIENTIFIC NOTE

Phenyl trimethicone's optical advantage (higher ri approaching hair cortex ri 1.56 vs pdms 1.40) is directly quantifiable as reduced total internal reflection at the hair-air interface. higher ri silicone films reduce the refractive index mismatch that causes specular scatter (matte appearance), increasing directional mirror-like reflection (shine) – the physical basis for its use as a premium hair shine ingredient.

Last Verified: 2026-03-12

Primary Sources: Cosing database,dow silicone technical data,cir safety assessment