Sodium Lauroyl Lactylate, commonly known as SLL, is a versatile ingredient widely used in various personal care and cosmetic products. It is a surfactant used to help stabilize emulsions, provide mild cleansing properties, and improve the texture and feel of products. In this article, we will explore the different uses of SLL in cosmetics and personal care products.
What is Sodium Lauroyl Lactylate?
Sodium Lauroyl Lactylate (SLL) is a unique liquid surfactant derived from sodium isostearoyl lactylate. As an emulsifier derived from the sodium salt of lactic acid esterified with lauric acid, SLL is the partially neutralized condensation product of lauric acid and lactic acid. It is used in hair and skin care products, providing an additional skin conditioning effect. As an environmentally friendly replacement for alkanolamides, it provides rheology control and aesthetically pleasing dense, creamy foam and is a common ingredient for many formulations.
Use of Sodium Lauroyl Lactylate in Cosmetics and Personal Care Products
Sodium lauroyl lactylate is primarily used as a surfactant in skin care products such as cleansers, toners, and moisturizers. As a surfactant, it helps to break down the oil and dirt on the skin’s surface, allowing them to be washed away with water. SLL is a mild surfactant that does not strip the skin of its natural oils, making it ideal for gentle and moisturizing skin care products.
SLL emulsifies many cosmetic products, including lotions, creams, and hair conditioners. Emulsifiers help blend oil and water-based ingredients, creating a smooth and homogeneous texture. SLL is a particularly effective emulsifier as it is compatible with a wide range of oils and is stable over a range of pH levels.
Another benefit of SLL is its ability to improve the texture and feel of products. It can help to thicken formulations and create a creamy, luxurious texture that is pleasant to use. Additionally, it can enhance the skin feel of products, making them feel smoother and more moisturizing.
Applications in Cosmetics and Personal Care Products
Here is a breakdown of the different functions of SLL:
| Function | Applications |
|---|---|
| Surfactant-Anionic | Due to the high foaming character of SLL, it may be employed as a primary surfactant in sulfate-free formulations or used as a secondary surfactant to add additional benefits. It is a biodegradable and bio-renewable replacement for petroleum-based surfactants. |
| Emulsifier | Works as an excellent emulsifier in creams and lotions, providing an alpha-hydroxy acid benefit at lower pH. |
| Skin Conditioning & Emolliency | Acts as an emulsifier and cleanser with conditioning properties for hair and skin, adding moisturizing and anti-static benefits. Sodium Lauroyl Lactylate can improve the texture and smooth feel of products |
| Antimicrobial | Being derived from lauric acid, SLL also serves to have antimicrobial characteristics. It meets the antimicrobial needs in deodorants, mouthwashes, and feminine hygiene products. |
| Foam Booster | Acts as a foam booster and stabilizer in shampoos and skin cleansers, imparting softness and moisturization. In cleansers, lactylates can improve the salt-thickening response of cleansing surfactant systems. |
| Thickener & Stabilizer | Thickens and increases the shelf life of products. Used as a mild thickening agent in cosmetics. |
Product Examples
Here are some examples of the many products Sodium Lauroyl Lactylate is found in:
| Type | Examples |
|---|---|
| Bath & Shower | Baby Wash, Face Wash, Laundry Products, Liquid and Bar Soaps, Body Wash, and Cleansers |
| Haircare | Shampoos and Hair Cleansers |
| Skincare | Moisturizers, Skin Cleanser/Protectant, Facial Cleansers, Lotions/Creams, Makeup Removers, and Shaving Creams |
| Fragrance Release | Sprays, deodorants |
| Oral Care | Dentifrices, Mouth Wash |
| Other | Vegetable & Fruit Disinfectants and Pet shampoos (as a surfactant) |
Properties of Sodium Lauroyl Lactylate
| Appearance at 25 °C | Clear Viscous Liquid |
| pH (10% Aqueous solution in water @25°C) | 5-6.5 |
| Molar Mass | 294.36 g/mol |
| Specific Gravity at 25°C | 1.05 – 1.15 |
| Solubility | Water Soluble |
| HLB Value | 14.4* |
| Acid Value, mgr. KOH/gr | 60-110 |
| Saponification Value mgr. KOH/gr | 260-320 |
| Odor | Characteristic |
| Boiling Point | 460.3ºC at 760mmHg |
| Shelf Life | 24-36 months |
Recommended Storage and Handling
- Store in tightly-closed containers in dry, well-ventilated locations at cool, ambient temperature
- Re-test/re-qualify 12 months after the date of manufacture
- Keep away from heat, sparks, and open flame
Sodium Lauroyl Lactylate Formulation Phases
Skin Care Cleansing Shower Gel
This Formulation illustrates the use of Sodium Lauroyl Lactylate in shower gel application. Sodium Lauroyl Lactylate is readily biodegradable & 100% naturally derived surfactant that forms rich and long-lasting foam. Very mild and has antimicrobial properties. Oil & alcohol soluble and can also be incorporated into transparent, aqueous systems.
| Phase | INCI Name | Trade Name | Supplier | Wt.% |
|---|---|---|---|---|
| A (Aqueous) | – Water – Cocamidopropyl Betaine – Decyl Glucoside – Glycerin – Disteareth-75 IPDI (and) PEG-7 Caprylic/Capric Glycerides (and) Water – Phenoxyethanol | – DI water – Foamtaine CAB – Pureact D – Glycerin – Dermothix 75L – Phenoxetol | – Alzo International – Innospec – Alzo International – Alzo International – Clariant | 43.6 20.0 20.0 0.5 7.4 0.5 |
| B (Oils) | – Sodium Lauroyl Lactylate – PPG-2 Isoceteth-20 Acetate – Ethylhexyl Pelargonate – Bis-PEG-15 Dimethicone/IPDI Copolymer | – Dermol SLLC-L – Cupl-PIC – Dermol OPG – Polyderm PPI-SI-WS | – Alzo International – Alzo International – Alzo International – Alzo International | 3.0 2.0 2.0 1.0 |
Formulation Procedure
- In the primary vessel, heat and mix Phase A to 50-55°C mixing until uniform
- In a side vessel, add phase B heat and mix until uniform at 50-55°C
- Add Phase B to Phase A and begin cooling to room temperature
Sodium Lauroyl Lactylate Formulation Considerations
- pH Compatibility lies between range 4-9
- Add to the water phase while formulating the ingredient
- Additional thickeners and co-emulsifiers recommended for optimal stability combine with equal parts of Sodium Stearoyl Lactylate for optimal stability and elegance
- Usage in Skin cleansing products (rinse-off products): Maximum up to 10%.
Additional surfactants recommended for optimal foam (formulate for a total of 30.0 to 40.0 total actives) - Typically usage includes- 10.0 to 30% in surfactant systems:
- As a primary surfactant – 20-40%
- As a secondary surfactant – 2-15%
- Use in leave-on products (tonics, dressings, and other hair grooming aids)- Max up to 7%
- The highest maximum use concentration in leave-on cosmetic products that are applied directly to the skin is 6.1% for Sodium Lauroyl Lactylate in body and hand products that are not sprayed — Typically 1.5 to 3.0% in emulsions
Source: Safety Assessment of Alkanoyl Lactyl Lactate Salts as Used in Cosmetics
Sodium Lauroyl Lactylate Safety & Regulatory Considerations
- The safety of the alkanoyl lactyl lactate salts is evaluated based on data received from the US Food and Drug Administration (FDA) and the cosmetics industry on the expected use of these ingredients in cosmetics. Sodium Lauroyl Lactylate is considered safe to be used in personal care products.
- SLL is a safe and well-tolerated ingredient in personal care and cosmetic products. It is biodegradable and does not accumulate in the environment, making it an environmentally friendly choice.
- Additionally, it is non-irritating and non-sensitizing, making it suitable for use on sensitive skin.
- Sodium Lauroyl Lactylate is classified as a weak or moderate skin sensitizer.
- The alkanoyl lactyl lactate salts reviewed in this safety assessment are not included on the European Union’s list of substances that are restricted or list of substances that are prohibited in cosmetic products.
Identification Numbers
| Chemical Name | Sodium 2-(1-carboxylatoethoxy)-1-methyl-2-oxoethyl laurate |
| CA Index Name | Sodium;2-(2-dodecanoyloxypropanoyloxy)propanoate |
| INCI Name | Sodium Lauroyl Lactylate |
| CAS Number | 13557-75-0 |
| EINECS Number | 236-942-6 |
Fun Facts About Sodium Lauroyl Lactylate
- SLL is derived from natural sources, including coconut oil and lactic acid. It is considered a natural ingredient and is approved for use in organic and natural personal care products.
- SLL is considered to be a mild and gentle ingredient, making it suitable for use in baby products such as baby wipes, lotions, and shampoos.
- SLL is used in pet care products, including shampoos and conditioners for dogs and cats.
- SLL is a popular ingredient in natural deodorants, which helps to neutralize odors and improve the product’s texture.
