What it is
Tributyl Citrate is the tributyl ester of citric acid, a clear, low-odor liquid. In cosmetics it is used mainly as a plasticizer to add flexibility to film-forming polymers and as an emollient that improves spreadability and skin feel. It is often found in sunscreens, nail products, and other formulas that rely on films.
Safety & warnings
Citrate esters are generally well tolerated in cosmetic use and are valued as alternatives to phthalate plasticizers; this material is not a recognized fragrance allergen.
Origin & sourcing
Synthetic; produced by esterifying citric acid with butanol.
Questions everyone asks
Why is tributyl citrate added to sunscreen?
It plasticizes film-forming ingredients and acts as an emollient, helping the product spread smoothly and feel less stiff on skin.
Is it a phthalate?
No; it is a citric acid ester used as a non-phthalate plasticizer.