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Common Name(s): Polymethyl methacrylate (pmma),acrylic microsphere,refractive index-matched soft-focus powder
CAS Number: N/a
DESCRIPTION
What It Does: Creates maximum skin soft-focus effect through refractive-index-matched mie scattering โ blurring pores and fine lines while maintaining accurate skin colour reproduction without the whitening caused by high-ri particles.
Why It's Used: Pmma's ri 1.49 precisely matches average skin ri providing optimal scattering efficiency: too-high ri (glass 1.52) over-scatters causing whitening; too-low ri creates high contrast scatter. pmma's ri match provides maximum blur-to-colour-shift ratio.
How It Works: Suspension polymerisation produces perfectly spherical pmma particles 5-20 um. mie scattering cross-section peaks when particle diameter is approximately the wavelength of light. pmma (ri 1.49) vs skin (ri ~1.46) provides small ri contrast generating forward-dominant diffuse scatter that softens specular skin reflections without strong whitening.
Typically Found In: Face powders,foundation,primers
TECHNICAL DETAILS
Primary Category: Active ingredient โ cosmetic active
Secondary Functions: Skin conditioning
Application Areas:
Facial Skincare
Body Care
Hair Care
Beard Care
Color Cosmetics (Makeup)
Dietary/Oral Supplements
Typical Concentration Range: 1%โ20%
SOURCING & ETHICS
Vegan Status: Conditional - supplier confirmation required
Halal Status: Unverified - supplier confirmation required
Source Notes: Commercially produced for cosmetic use. verify vegan/halal status with supplier. [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 โ very low
Comedogenicity Rating: 0/5 โ non-comedogenic
Sensitivity Concerns: Well-tolerated by most skin types.
Safe for Sensitive Skin: Yes
SAFETY & COMPATIBILITY
Safety Profile: Good safety profile at recommended concentrations. ewg score: 1โ2.
Works Well With: Standard skincare actives
Avoid Combining With: No known significant incompatibilities
SCIENTIFIC NOTE
Eu microplastic regulatory note: insoluble spherical pmma particles in rinse-off products may fall within 2023/2055 restriction scope. leave-on make-up is likely exempt but rinse-off use requires compliance verification by particle size and solubility criteria.
Last Verified: 2026-03-12
Primary Sources: Cosing database,eu regulation 2023/2055,pmma soft-focus optical review