Sodium lauroyl Isethionate is a chemical compound, a non aggressive, economical and ecological surfactant and is added in cosmetic products.

The name defines the structure of the molecule

• "Sodium". It's an alkali metal, symbol Na, with atomic number 11. It's an essential element for life and plays a key role in regulating blood pressure and plasma volume.
• "Lauroyl". Indicates the presence of a lauroyl group, which is the acid derivative of lauric acid. Lauric acid is a saturated fatty acid with 12 carbon atoms.
• "Isethionate". It's the salt or ester of isethionic acid, a sulfonic acid. It has the chemical formula C₂H₅O₃S.

Description of the raw materials used in its production:

• Lauric Acid - A medium-chain fatty acid found in various natural sources such as coconut oil and palm oil.
• Isethionic Acid (2-hydroxyethanesulfonic acid) - A sulfonic acid used in the synthesis of sodium lauroyl isethionate.

Industrial chemical synthesis of Sodium Lauroyl Isethionate, step by step:

• Esterification - Lauric acid is reacted with isethionic acid in the presence of an acid catalyst to form lauric isethionate ester.
• Neutralization - The lauric isethionate ester is then reacted with sodium hydroxide (NaOH) to neutralize the acid and form the salt, known as sodium lauroyl isethionate.
• Isolation - After the reaction reaches completion, the formed sodium lauroyl isethionate precipitates out and is isolated via filtration.
• Purification - The crude sodium lauroyl isethionate is purified through crystallization or other purification techniques.
• Quality control - Once Sodium Lauroyl Isethionate is obtained, it undergoes various quality checks to ensure it meets specifications.

It appears in the form of a white powder. 

What it is for and where

Cosmetics

Antistatic agent. Static electricity build-up has a direct influence on products and causes electrostatic adsorption. The antistatic ingredient reduces static build-up and surface resistivity on the surface of the skin and hair.

Cleansing agent. Ingredient that cleanses skin without exploiting the surface-active properties that produce a lowering of the surface tension of the stratum corneum

Foaming.  Its function is to introduce gas bubbles into the water for a purely aesthetic factor, which does not affect the cleaning process, but only satisfies the commercial aspect of the detergent by helping to spread the detergent. This helps in the commercial success of a cleansing formulation. Since sebum has an inhibiting action on the bubble, more foam is produced in the second shampoo. In practice, it creates many small bubbles of air or other gases within a small volume of liquid, changing the surface tension of the liquid.

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.

Skin conditioning agent. It is the mainstay of topical skin treatment as it has the function of restoring, increasing or improving skin tolerance to external factors, including melanocyte tolerance. The most important function of the conditioning agent is to prevent skin dehydration, but the subject is rather complex and involves emollients and humectants that can be added in the formulation.

Surfactant - Cleansing agent. Cosmetic products used to cleanse the skin utilise the surface-active action that produces a lowering of the surface tension of the stratum corneum, facilitating the removal of dirt and impurities. 

Safety

The Cosmetic Ingredient Review (CIR) Expert Panel (Panel) gave a favorable opinion on the safety of Sodium lauroyl Isethionate, deeming this chemical compound safe in current use and concentration practices in cosmetics when formulated to be nonirritating (1).

Commercial applications 

Skin Cleansing Products. Used in facial cleansers, body soaps, and shower gels for its ability to remove dirt and oil from the skin.

Shampoo and Hair Products. Acts as a foaming and cleansing agent in shampoos and other hair care products.

Shaving Products. Can be found in shaving creams and gels to help create a stable foam.

Cosmetics. Used in some cosmetic products as an emulsifier to help mix water-based and oil-based ingredients.

Oral Care Products. It can be used in some toothpastes as a foaming agent.

"Sodium lauroyl Isethionate, studies"

• Molecular Formula   C₁₄H₂₇NaO₅S
• Molecular Weight   330.415 g/mol
• CAS  7381-01-3
• EC number   230-949-8

Synonyms:

• sodium 2-(dodecanoyloxy)ethanesulfonate
• Sodium 2-sulfoethyl laurate
• Sodium ethyl 2-sulfolaurate
• Sodium lauroylisethionate
• Sodium 2-sulfoethyldodecanoate
• Lauroyl isethionate, sodium salt
• Dodecanoic acid, 2-sulfoethyl ester, sodium salt
• 2-Sulfoethyl dodecanoate sodium salt
• Lauric acid, ester with 2-hydroxyethanesulfonic acid sodium salt

References_____________________________________________________________________

(1) Burnett, C. L., Heldreth, B., Bergfeld, W. F., Belsito, D. V., Hill, R. A., Klaassen, C. D., ... & Andersen, F. A. (2017). Amended safety assessment of isethionate salts as used in cosmetics. International journal of toxicology, 36(1_suppl), 5S-16S.