Ingredient
C11-15 ALKETH-9
Substance information
"Alketh-" refers to a PEG ether of an alkanol (alkyl alcohol). The preceding numbers "C x-y" refer to the length of the alkyl (carbon) chains. The number behind "alketh-" refers to the average number of molecular units -CH2-CH2-O-.
Function(s) of this ingredient in cosmetic products
SURFACTANT - EMULSIFYING
Allows the formation of finely dispersed mixtures of oil and water (emulsions)
Origin
synthetic
Background information on use in cosmetics
Emulsifiers are often used in cosmetics as excipients. They allow actually unmixable components like oil and water to be brought in a permanently stable emulsion. In this way both aqueous and oily care and active ingredients can be used in one and the same product in cosmetics. Emulsifiers are able to do that since their molecules consist of a lipophilic and a hydrophilic part. In this way they can reduce the interfacial tension which actually exists between two incompatible substances like fat and water. Emulsifiers are, more particularly, used for creams, lotions and cleansing agents. At present emulsifiers are, however, more than only excipients which keep an emulsion stable. Fatty acid esters on the basis of sugar, lecithin or glycerin monodistearate contribute, for instance, to improving the moisture balance of the skin and are, therefore, also considered as cosmetic active ingredients. Polyethylene glycols (INCI: PEG-...) are poly condensation products of ethylene glycol, or polymerisation products of ethylene oxide. The number added to the name refers to the mean number of ethylene oxide units in the substance. The consistency of the PEG derivatives is increasingly solid with a growing degree of polymerisation. PEGs with a mean molar mass of up to 600 g/mol are liquid, up to 1,000 g/mol wax-like and from 4,000 g/mol solid wax-like substances. By mixing solid and liquid components, products of a creamy consistency are obtained which are used as water-free and water rinse-off bases. With growing molar mass water solubility and hygroscopicity (ability to absorb moisture) of the polyethylene glycols decrease.
Information on safe use
Claudia Fruijtier-Pölloth: Safety assessment on polyethylene glycols (PEGs) and their derivatives as used in cosmetic products. In: "Toxicology" (2005), No. 214, P. 1-38. Publisher: Elsevier Ireland Ltd.
Belongs to the following substance groups
Regulating cosmetics
Cosmetics Ingredients are subject to regulation. Please note, different regulations may apply to cosmetic ingredients outside the EU.