Hada Labo Blemish & Oil Control Hydrating Lotion Versus Eucerin ProACNE Solution Toner

Water. It's the most common cosmetic ingredient of all. You'll usually see it at the top of ingredient lists, meaning that it makes up the largest part of the product.

So why is it so popular? Water most often acts as a solvent - this means that it helps dissolve other ingredients into the formulation.

Butylene Glycol (or BG) is used within cosmetic products for a few different reasons:

• It is a solvent, meaning that it helps to dissolve other ingredients. This also enhances the absorption of the product into one's skin.
• It is a humectant, which means that it helps attract moisture into the skin.
• It helps improve product application.
• It has mild preservative properties.

Overall, Butylene Glycol is a safe and well-rounded ingredient that works well with other ingredients.

Peg-40 Hydrogenated Castor Oil is derived from castor oil and polyethylene glycol (PEG). It is used as a emollient and emulsifier.

As an emulsifier, it helps prevent ingredients from separating. It also helps make the other ingredients more soluble; it is often used to solubilize fragrances. This increases spreadability and elongates shelf life in a product.