Oleth-3

(Z) -9-Octadecen-1-ol ethoxylated

Oleth-3 is the INCI name of polyoxyethylene glycol oleyl ether. As an emulsifier, emulsion stabiliser or dispersant, Oleth-3 is widely used in cosmetics and in many industrial applications. It is a component of cosmetics, plant protection products, and numerous detergents.

General characteristics

In the INCI nomenclature (the INCI nomenclature is the international nomenclature for cosmetic ingredients and substances, standardising the system of naming ingredients in cosmetics), Oleth-3 is a surfactant mainly used as an emulsifier. The chemical name of this compound is ethoxylated (Z) -9-octadecen-1-ol and its CAS number is 9004-98-2.

The basic physical and chemical characteristics of Oleth-3 are:

• clear or cloudy liquid (at room temperature),
• colour: from straw to light yellow,
• a faint odour,
• moderately lipophilic properties,
• molar mass: approx. 400 g/mol,
• iodine colour (at 50 ᵒC): maximum 10,
• pH of a 1% aqueous solution: from 5.5 to 8.5,
• low water solubility,
• solidification point: approx. 0 ᵒC,
• density: approx. 0.907 g/ml (at 20 ᵒC),
• biodegradability,
• resistance in oxidising and reducing environments and in the presence of hard water.

Oleth-3 is miscible with selected base oils. It dissolves in mineral base oils as well as in methyl esters of rapeseed oil. Oleth-3 is not compatible with rapeseed oil alone.

Applications of Oleth-3

As an ingredient of creams or body lotions, it acts as a W/O emulsifier. It supports the formation of such emulsions, i.e., systems where the water phase is dispersed in a homogeneous oil phase. Its presence in the product also influences the rheological properties, i.e., the viscosity of the cosmetic product, which significantly affects its consistency and performance. Oleth-3 can be used as a hair colouring and styling component.

As an emulsifier, Oleth-3 is also used in plant protection products. In addition, it is used in cutting fluids (it does not abrade  common construction materials) and in preparations for the flotation of non-ferrous metal ores. As a component of the above-mentioned preparations, it improves the effectiveness of combining ingredients of a different chemical nature. It also shows good dispersing properties.

This compound is also a component of household chemicals. It is found in washing agents and washing compositions, where it acts as a dispersant and as a softening agent. In addition, furniture-care sprays contain Oleth-3. It is perfect for polishing various surfaces.

Oleth-3 – the safety of use in cosmetic products

This compound is recognised as safe for use in cosmetic products. The following concentrations should not be exceeded: 0.3 to 4% in leave-on preparations and 7 to 10% in rinse-off products. Oleth-3 has mild to moderate skin and eye irritation potential.