SCI - Sodium cocoyl isethionate

INCI: Sodium Cocoyl Isethionate

SCI is an exceptionally mild surfactant (surface-active agent), derived from coconut oil. It is used in shampoos, shower gels (including for children), and facial cleansers. Because it comes in the form of a concentrated powder, very little is needed in products. In addition to its mildness, SCI is also distinguished by the luxurious, creamy lather it gives to products. It does not dry out the skin but instead leaves a pleasant, silky feel. During use it does not damage the protective barrier on the skin, making it very suitable for dry, delicate, and sensitive skin*. Unlike many other surfactants, SCI is active in both soft and hard water.

Because SCI has poor solubility in water, it is very suitable for making solid shampoos, as it will ensure the shampoo does not dissolve too quickly.

SCI is derived from natural materials, but due to the manufacturing processes it is not permitted in certified natural cosmetics.

Ideal for use in: shampoos, shower gels, makeup removers (including for eyes), foaming baths, shaving foams, liquid soaps, products for babies and children.

Solubility: limited solubility in water, can be heated.
Usage: most commonly used between 2% and 20%, in solid shampoos up to 70%
Surfactant type: anionic
pH of 10% aqueous solution: 4.0–6.0
Active substance: min. 82%
Free fatty acid content: up to 13%

Tip: SCI is difficult to dissolve in water, but is soluble in other surfactants. It is therefore recommended to heat it until it softens, together with the other surfactants in the formulation (for example decyl glucoside, coco glucoside). During the heating process the surfactant mixture should be stirred occasionally. When heated it does not melt completely but softens into a paste-like structure. This mixture is then added to hot water while mixing vigorously.

*Ghosh, S., & Blankschtein, D. (2008). Why is sodium cocoyl isethionate (SCI) mild to the skin barrier?–An in vitro investigation based on the relative sizes of the SCI micelles and the skin aqueous pores. International Journal of Cosmetic Science, 30(4), 310-310.