Castor Seed Oil Aminopropanediol Amides/Esters

Castor Seed Oil Aminopropanediol Amides/Esters is a modified derivative of castor seed oil—a plant-derived ingredient processed to create amides and esters with aminopropanediol. This chemical modification enhances the oil's ability to integrate into skincare formulations whilst retaining emollient properties.In skincare products, it functions as both an emollient and humectant, meaning it helps to soften the skin surface and support moisture retention within the outer layers of the epidermis.

As an emollient, this ingredient sits on the skin's surface and creates a thin, occlusive layer that slows transepidermal water loss—the natural evaporation of moisture from the skin. This occlusive action helps to trap hydration and can make the skin feel smoother and more hydrated.Its humectant properties allow it to draw water molecules from the air and deeper skin layers toward the stratum corneum (the outermost layer), further supporting skin hydration and conditioning.

This ingredient is typically used in moisturisers, serums, and conditioning treatments at concentrations that support hydration without leaving an overly heavy or greasy residue. It works well in combination with other humectants and occlusives. For best results, apply to damp skin to maximise moisture absorption, and allow formulations containing this ingredient to fully absorb before layering additional products.

Generally well-tolerated in skincare formulations. Those with known sensitivities to castor oil or plant-derived ingredients should patch-test first, though adverse reactions are uncommon at typical cosmetic concentrations.