Armani Beauty Luminous Silk Concealer Versus Charlotte Tilbury Magic Away Liquid Concealer

Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.

Topically, glycerin does several things at once:

Hydrogenated Polyisobutene is a synthetic polymer. Polymers are compounds with high molecular weight. Hydrogenated Polyisobutene is an emollient and texture enhancer.

In one study, Hydrogenated Polyisobutene showed better skin hydration levels than Caprylic/Capric Triglyceride. As an emollient, it helps keep your skin soft and hydrated by trapping moisture in.

Hydroxyacetophenone is antioxidant with skin conditioning and soothing properties. It also boosts the efficiency of preservatives.

Though naturally occuring in Norwegian spruce needles, this ingredient is usually synthetically created.

Propanediol is an all-star ingredient. It softens, hydrates, and smooths the skin. 

It’s often used to:

Trisodium Ethylenediamine Disuccinate is used to help stabilize a product.

It is a chelating agent, meaning it helps prevent metal ions from binding to other ingredients. This prevents unwanted reactions in products. Metal ions can come into a product via the water ingredient. They are found in trace amounts and are not known to be harmful.

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.