The Ordinary UV Filters SPF 45 Serum

Ethylhexyl Salicylate is an organic compound used to block UV rays. It primarily absorbs UVB rays but offers a small amount of UVA protection as well.

Commonly found in sunscreens, Ethylhexyl Salicylate is created from salicylic acid and 2-ethylhexanol. You might know salicylic acid as the effective acne fighter ingredient and BHA.

Octocrylene protects skin from sun damage. It absorbs UV-B with peak absorption of 304 nm. It is a common sunscreen ingredient and often paired with avobenzone, a UVA filter. This is because octocrylene stabilizes other sunscreen ingredients by protecting them from degradation when exposed to sunlight. Octocrylene is a photostable ingredient and loses about 10% of SPF in 95 minutes.

Octocrylene also acts as an emollient, meaning it helps skin retain moisture and softens skin. It is oil-soluble and hydrophobic, enhancing water-resistant properties in a product.

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.

We don't have a description for Behenyl Acrylate yet.

We don't have a description for Biosaccharide Gum-2 yet.

Butyloctyl Salicylate is a chemical UV filter structurally similar to octisalate. It is a photostabilizer, SPF booster, emollient and solvent. This ingredient helps evenly spread out ingredients.

According to a manufacturer, it is suitable for pairing with micro Titanium Dioxide, Zinc Oxide, and pigments.

Chlorphenesin is a synthetic preservative. It helps protect a product against bacteria in order to extend shelf life. In most cases, Chlorphenesin is paired with other preservatives such as phenoxyethanol and caprylyl glycol.

Chlorphenesin is a biocide. This means it is able to help fight the microorganisms on our skin. It is also able to fight odor-releasing bacteria.

This ingredient is also known as Solafresh. It is an emollient, UV absorber, and solvent.

According to a manufacturer, this ingredient helps:

This ingredient is a silicone elastomer that works as a texture enhancer, adds a silky slip, and also helps absorb excess oil.

Because it's a large macromolecule that's insoluble in water and chemically inert, it's not expected to penetrate or be absorbed into skin.

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:

Isododecane is a fragrance, emollient, and solvent.

As an emollient, it helps your skin stay soft and hydrated. Emollients help trap moisture into your skin.

Magnesium Sulfate is a salt. More specifically, it is an epsom salt, or the bath salt used to help relieve muscle aches.

Despite having ‘sulfate’ in the name, it isn’t a surfactant or cleansing agent like sodium lauryl sulfate. Unlike those sulfates, magnesium sulfate doesn’t have the same cleansing or foaming properties (it's simply a type of salt).

We don't have a description for Acetyl Carnosine yet.

p-anisic acid is an aromatic compound that is naturally found in some plants. It is mainly used as a fragrance ingredient but also has preservative and antimicrobial properties.

The effectiveness of this ingredient as a preservative and antimicrobial depends on the pH (with more acidic being better). This is the reason you'll see this ingredient bundled with other preservatives.

Pentylene glycol is typically used within a product to thicken it. It also adds a smooth, soft, and moisturizing feel to the product. It is naturally found in plants such as sugar beets.

The hydrophilic trait of Pentylene Glycol makes it a humectant. As a humectant, Pentylene Glycol helps draw moisture from the air to your skin. This can help keep your skin hydrated.

Phenoxyethanol is a preservative that has germicide, antimicrobial, and aromatic properties. Studies show that phenoxyethanol can prevent microbial growth. By itself, it has a scent that is similar to that of a rose.

It's often used in formulations along with Caprylyl Glycol to preserve the shelf life of products.

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

It’s often used to:

Sodium Citrate is the sodium salts of citric acid. In skincare, it is used to alter pH levels and acts as a preservative.

Its main functions are to maintain the pH of a product and neutralize metal ions.

Phospholipids are a family of skin-identical lipids that makeup the structural backbone of every cell membrane in your body.

In cosmetics, they function as skin conditioning agents with emulsifier and surfactant properties. They're typically sourced from soybean or sunflower lecithin (or sometimes egg yolk or marine sources).

Sphingolipids are a major class of lipids in cell membranes. This ingredient has emollient, skin conditioning, and skin protecting properties.

Certain ceramides are considered sphingolipids (Ceramide NS and Ceramid AP), but not all sphingolipids are ceramides.

Tocopherol is a fat-soluble antioxidant known as Vitamin E.

You'll find this ingredient in the vast majority of skincare (for good reason). It works to neutralize free radicals, or unstable molecules generated by UV exposure, pollution, and other environmental stressors, before they can cause oxidative damage to your skin cells.

We don't have a description for Tri (Polyglyceryl-3/Lauryl) Hydrogenated Trilinoleate yet.

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.