Silicone Quaternium-18 is a quaternary ammonium compound that combines silicone with a quaternary ammonium salt. This ingredient is used primarily in cosmetic formulations for its conditioning and emollient properties. It enhances the texture and smoothness of products, providing a silky feel to the skin and hair.

Chemical Composition and Structure

Chemical Composition: Silicone Quaternium-18 is a derivative of a quaternary ammonium compound combined with silicone. The quaternary ammonium component is a positively charged nitrogen atom bound to four alkyl groups, while the silicone portion typically includes polydimethylsiloxane or similar silicone polymers.

Structure: The structure features a quaternary ammonium cation attached to a silicone backbone. The combination results in a compound that provides conditioning effects and enhances the stability of cosmetic formulations.

Physical Properties

Appearance: Typically found as a clear or slightly opaque liquid or a solid that dissolves in water.
Solubility: Soluble in water, allowing easy integration into aqueous formulations.
pH: Compatible with a wide range of pH levels, making it suitable for various cosmetic products.

Production Process

The production of Silicone Quaternium-18 involves several key steps:

Synthesis of Quaternary Ammonium Compound: The quaternary ammonium compound is synthesized through the quaternization of a tertiary amine with an alkyl halide or similar reagent.
Silicone Integration: The quaternary ammonium compound is then combined with silicone polymers, such as polydimethylsiloxane, through chemical reactions.
Purification and Processing: The resulting mixture is purified and processed to achieve the desired purity and consistency.
Formulation: The purified product is incorporated into cosmetic formulations during the manufacturing process.

Applications

Medical: Not commonly used in medical applications.
Cosmetics: Widely used in hair conditioners, shampoos, and skincare products. It provides conditioning benefits, improves texture, and enhances the overall feel of the products.
Food: Not used in food products.

Environmental and Safety Considerations

Generally regarded as safe for topical application. However, like all compounds, it should be used according to established guidelines to avoid potential allergic reactions or skin irritations. Individuals with sensitive skin or allergies should exercise caution. It is essential to ensure that the compound is sustainably sourced and free from harmful chemicals.

INCI Functions:


Skin conditioning agent - Emollient. Emollients have the characteristic of enhancing the skin barrier through a source of exogenous lipids that adhere to the skin, improving barrier properties by filling gaps in intercorneocyte clusters to improve hydration while protecting against inflammation. In practice, they have the ability to create a barrier that prevents transepidermal water loss. Emollients are described as degreasing or refreshing additives that improve the lipid content of the upper layers of the skin by preventing degreasing and drying of the skin. The problem with emollients is that many have a strong lipophilic character and are identified as occlusive ingredients; they are oily and fatty materials that remain on the skin surface and reduce transepidermal water loss. In cosmetics, emollients and moisturisers are often considered synonymous with humectants and occlusives.

Hair conditioning agent. A significant number of ingredients with specific and targeted purposes may co-exist in hair shampoo formulations: cleansers, conditioners, thickeners, matting agents, sequestering agents, fragrances, preservatives, special additives. However, the indispensable ingredients are the cleansers and conditioners as they are necessary and sufficient for hair cleansing and manageability. The others act as commercial and non-essential auxiliaries such as: appearance, fragrance, colouring, etc. Hair conditioning agents have the task of increasing shine, manageability and volume, and reducing static electricity, especially after treatments such as colouring, ironing, waving, drying and brushing. They are, in practice, dispersants that may contain cationic surfactants, thickeners, emollients, polymers. The typology of hair conditioning agents includes: intensive conditioners, instant conditioners, thickening conditioners, drying conditioners. They can perform their task generally accompanied by other different ingredients.
Synonyms:

CAS: