Parethe

The polyoxyethylene ethers of synthetic fatty alcohols are called "pareth" (for comparison see: laurethe as polyoxyethylene ether of lauryl alcohol; steareth as polyoxyethylene ether of stearyl alcohol, etc.).

Polyalkylene glycol ethers are non-ionic surfactants whose lipophilic part consists of fatty alcohols (e.g. lauryl alcohol, palmitic alcohol, stearyl alcohols etc.). The hydrophilic part is formed by short-chain polyethylene glycols (polyoxyethylene). In the designation of fatty alcohol polyglycol ethers, the inserted numbering means the average number of ethylene oxide units per mole. The C numbering (e.g. C12-15) designates a synthetic C12-C15 fatty alcohol.

For example, the INCI designation C12-15 Pareth -9 defines a polyoxyethylene ether of 9 ethylene oxide units per mole with a mixture of synthetic C12-C15 fatty alcohols.