Sodium Laureth Sulfate (SLeS)

What is it? Sodium Laureth Sulfate (sodium lauryl ether sulfate/SLeS) is an anionic surfactant made from coconuts. It should not be confused with Sodium Lauryl Sulfate (SLS)—SLeS is much milder.
INCI Sodium Laureth Sulfate
Appearance Clear, viscous liquid or a smooth, thick paste—it is available at different concentrations and more concentrated versions are thicker.
Usage rate The CIR has not noted a maximum usage rate. Let the desired total active surfactant matter of your end product be your guide.
Texture Slippery, detergenty
Scent Characteristically detergenty
Active Surfactant Matter 26–70% (this varies with format; confirm with your supplier)
pH 7.5 (10% solution)
Charge Anionic
Solubility Water
Why do we use it in formulations? Sodium Laureth Sulfate (SLeS) is an excellent lathering surfactant and is a great choice for a primary surfactant in any kind of foaming/cleansing product. It is also a fairly decent solubilizer.
Do you need it? No
Refined or unrefined? Sodium Laureth Sulfate (SLeS) only exists as a refined product.
Strengths Fantastic lather, great cleansing.
Weaknesses It is still a sulfate, which some people prefer to avoid due to possible irritation or colour-treated hair. It also tends to get confused with SLS, which isn’t really a weakness of the product itself.
Alternatives & Substitution Generally speaking, you’d hope to replace any surfactant with one that is the same format and has the same charge. A similar pH and ASM would be nice, but those differences can be accommodated in the formulation. It is also nice if the surfactant has a similar feel and produces similar lather.

If you need a substitute for Sodium Laureth Sulfate (SLeS), Sodium coco sulfate is another sulfate you may have on hand, though you will likely need to dissolve it in some water to create a liquid solution with a similar concentration to use it in place of SLeS. You can try Sodium C14-16 Alpha Olefin Sulfonate (Bio-Terge AS40) as an alternative liquid anionic non-sulfate surfactant, or even Caprylyl/Capryl Glucoside, though it is non-ionic and does not have the same high-foam properties.

How to Work with It Include it in the water phase of your formulations; it can be hot or cold processed.
Storage & Shelf Life Stored somewhere cool, dark, and dry, Sodium Laureth Sulfate (SLeS) should last at least two years.
Tips, Tricks, and Quirks There is quite a lot of misinformation about the safety of SLeS. I recommend giving this a read. Neither SLS or SLeS are carcinogens.
Recommended starter amount 250g (0.5lbs) (solid surfactant bars and bath bombs will use lots!)
Where to Buy it  Buy it from an online DIY ingredient supplier.

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Some Formulations that Use Sodium Laureth Sulfate (SLeS)


Posted on

February 14, 2019