A polyethylene glycol diester of isostearic acid, used as an emulsifier.
What it is
PEG-12 diisostearate is the diester of isostearic acid, a branched C18 fatty acid, with polyethylene glycol containing an average of 12 ethylene oxide units. CosIng lists it as an emulsifying surfactant.
Where it is used
Appears on the ingredient lists of a small number of products.
Limits of interpretation
The INCI list shows which ingredients are present, not how much of each. Above 1%, ingredients are listed in descending order of weight; below 1% the order is free.
The number 12 is an average, so the raw material is a mixture of molecules of different sizes.
Functions
- Surfactant – emulsifying
- Helping suspensions or dispersions of liquids in a second liquid by reducing the surface tension of the substances to be emulsified.
EU regulation
This ingredient is not listed in the annexes of Regulation (EC) No 1223/2009 in the CosIng data.

