Quick answer

Used as a film former and skin conditioning ingredient; Is a powder with round-shaped particles; Is used in amounts up to 55.2% in cosmetics; Deemed safe as used in cosmetics, with no evidence of toxicity or sensitization

Polymethylsilsesquioxane

Updated

Polymer formed by hydrolysis and condensation of methyltrimethoxysilane

Purpose

A polymer that acts as a film former and skin conditioning ingredient in skin care products. Used in amounts up to 55.2% and has been ruled safe as used in cosmetics.

Rating

GOOD

Category

Silicone, Film-Forming Agent, Suspending/Dispersing Agent

INCI Purpose

OPACIFYING

Risks

Microplastic — Solid synthetic polymer that does not break down and is washed into waterways

Alternative Names

Hair Profile

Functions

Silicone

At a Glance

Used as a film former and skin conditioning ingredient

Is a powder with round-shaped particles

Is used in amounts up to 55.2% in cosmetics

Deemed safe as used in cosmetics, with no evidence of toxicity or sensitization

Article

Polymethylsilsesquioxane is a polymer formed from the condensation and hydrolysis of the silicone methyltrimethoxysilane. In cosmetics, it functions primarily as a film former and skin conditioning ingredient. In its raw form, it is a powder with round particles.

In a survey of cosmetic formulations, polymethylsilsesquioxane was found to be used in amounts as high as 55.2%, but most often at concentrations of 4.9% or less. The independent Cosmetic Ingredient Review panel found that polymethylsequioxane is safe as used in cosmetics, with no evidence of toxicity or sensitization. This silicone polymer is also not known to clog pores.

References