# ETHYL POLYSILSESQUIOXANE

URL: https://app.greenveil.ai/ingredients/ingredient_inci_ethyl_polysilsesquioxane
Categories: beauty
Functions: Nail conditioning
Identifier: ETHYL POLYSILSESQUIOXANE

> ETHYL POLYSILSESQUIOXANE: Used in cosmetics as a nail conditioning agent. Canonical ingredient record built from 1 public-source records. Compiled from 1 published data source.

## Safety assessment

- Chemical concern: not yet assessed
- Is it a concern? We haven't assessed a concern score for this ingredient yet. It is listed for cosmetic use in the EU.
- Rationale: Canonical ingredient record built from 1 public-source records.

## Regulatory status

- EU: Active — Ethyl Polysilsesquioxane is a resinous material composed of a mixture of three-dimensional siloxane polymers and oligomers with cage structures. For the oligomers, each silicon atom in the polysilsesquioxane is connected via oxygen atoms to three other silicon atoms and can be represented by the empirical formulation RSiO3/2, where R represents the ethyl group. For the larger polymeric polysilsesquioxanes, some of the silicon atoms are not connected to other silicon atoms and instead have a silanol (SiOH) group. Ethyl Polysilsesquioxane is prepared by the hydrolysis and condensation of ethyl trimethoxysilane.

## Expert safety opinions

- SCCS (EU Scientific Committee on Consumer Safety): no opinion on file.
- CIR (Cosmetic Ingredient Review (US expert panel)): no opinion on file.

## Data sources

- CosIng (updated 2026-09-23): https://ec.europa.eu/growth/tools-databases/cosing/details/93234

_Assessed by Greenveil._