A tertiary fatty amine used as a hair-conditioning agent and emulsifier, regulated in Annex III.
What it is
Dimethyl stearamine is N,N-dimethyloctadecylamine, a tertiary amine with one C18 alkyl chain and two methyl groups. In acidic formulas it becomes cationic. CosIng lists it as an antistatic, emulsifying and hair-conditioning ingredient. In the EU it is covered by an entry in Annex III (substances subject to restrictions) for trialkylamines and their salts.
Where it is used
Found mainly in hair conditioners, hair masks and other hair care 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.
See the EU regulation section for the applicable limits and conditions, which differ between leave-on and rinse-off products.
Functions
- Antistatic
- Preventing and/or reducing static electricity by neutralising electrical charge on surfaces.
- Surfactant – emulsifying
- Helping suspensions or dispersions of liquids in a second liquid by reducing the surface tension of the substances to be emulsified.
- Hair conditioning
- Enhancing the appearance and feel of hair. Leaving the hair easy to comb, supple, soft and shiny and/or imparting volume, lightness, gloss, texture, etc.
EU regulation
- Product type
- (a) Leave-on products (b) Rinse-off products
- Maximum concentration
- (a) 2.5%
- As of
- 3 November 2026 · (EC) 2009/1223