Sodium Isostearoyl Lactylate (ISL)

Sodium Isostearoyl Lactylate (ISL)

A multifunctional lactylate emulsifier and conditioning ingredient that improves emulsion quality, skin feel, moisture retention and overall formulation performance across skincare and haircare systems.

INCI Name: Sodium Isostearoyl Lactylate

CAS Number: 66988-04-3

Appearance: Clear to pale yellow viscous liquid

HLB: Approximately 5.9

Function: Emulsifier, co-emulsifier, conditioning agent, secondary surfactant, sensory modifier

Sodium Isostearoyl Lactylate is a versatile acyl lactylate designed for formulators seeking more than basic emulsification. It helps support stable, elegant emulsions while contributing a soft, conditioned skin feel and improved moisture retention, making it especially useful in creams, lotions, cleansers, barrier-care products and conditioning formulations.

Its multifunctional character allows ISL to perform across both leave-on and rinse-off systems. In emulsions, it can support texture and stability while improving sensory quality. In haircare and cleansing products, it can contribute conditioning, softness and mild secondary surfactant performance, making it a valuable functional ingredient for streamlined, high-performance formulations.

Supplied as a cosmetic raw material for formulation use.

Performance Profile

ISL can be used as part of an emulsifier system in creams and lotions or as a multifunctional supporting ingredient in cleansers, shampoos and conditioners. Its liquid form also makes it convenient to incorporate into oil-phase systems without the handling challenges associated with waxy or powdered emulsifiers.

Key Benefits

• Supports the formation and stability of cosmetic emulsions.
• Improves skin softness, smoothness and conditioned after-feel.
• Helps support moisture retention in skin and hair formulations.
• Provides useful conditioning performance in shampoos and conditioners.
• Can function as a secondary surfactant in cleansing systems.
• Helps improve the overall sensory profile of both leave-on and rinse-off products.

Why Formulators Choose It

• Combines emulsification and conditioning in one ingredient.
• Liquid format simplifies handling and incorporation.
• Useful across skincare, haircare and cleansing applications.
• Can complement primary emulsifiers in more sophisticated emulsion systems.
• Suitable for formulations where both structure and sensory performance matter.
• Provides a lighter, softer finish than many conventional heavy emulsifier systems.

Suggested Use Levels

• 1–3% in creams, lotions and lightweight emulsions.
• 1–5% in shampoos, conditioners and cleansing systems.
• Up to 10% in specialized formulations where higher functional loading is required.

Ideal Applications

• Face creams and moisturizers
• Body lotions
• Barrier-support formulations
• Facial cleansers
• Shampoos
• Hair conditioners
• Body washes
• Baby care products
• Sunscreen emulsions
• Makeup bases

Formulation Notes

• Add to the oil phase of the formulation.
• Suitable for use as part of an emulsifier or co-emulsifier system.
• Can be used in both leave-on and rinse-off personal care products.
• Pairs well with fatty alcohols, nonionic emulsifiers and other lipid-phase structuring ingredients.
• May also be used alongside surfactants in cleansing and haircare systems.
• Final viscosity, emulsion structure and sensory profile depend on the complete emulsifier system and oil-phase composition.
• Evaluate compatibility, stability and performance in the complete finished formulation before scale-up.

A practical choice for formulators looking to combine emulsification, conditioning and sensory refinement within a single multifunctional ingredient.

Documents

• Certificate of Analysis (COA)
• Safety Data Sheet (SDS)