What is an Emulsifier in Skin Care?
In this Article
What is An Emulsifier
What Are the Common Emulsifiers in Skincare
Are Emulsifiers the Same as Surfactants
Are Surfactants and Emulsifiers Bad for the Skin
As we’ve spoken about lots of times here at Sönd, the world of skincare is full of odd sounding, unpronounceable and downright confusing words (and plenty of jargon). In the past. We’ve gone into detail on many ingredients with strange or chemistry lab sounding names.
These include squalane (a lipid that keeps the skin well hydrated), linalool (a beautifully scented plant based compound used to give fragrance to skin care products) and argireline (a peptide that can help to restore youthfulness and is said to be the closest we can get to Botox without a needle!).
But sometimes, it’s actual groups of ingredients that cause confusion, especially when they sound like they belong somewhere other than in skincare parlance. Emulsifiers in skincare are one such group of ingredients.
They might sound like they’re from a DIY shop, as anyone who’s ever painted a wall will be familiar with white emulsion, used to whitewash walls or as a base coat. But emulsifiers (that have nothing to do with colour) play an important role in some skincare products.
So, what are emulsifiers in skincare? Here’s everything you need to know about emulsifiers in skincare!
What is An Emulsifier?
Emulsifier is the name given to a group of molecules that allow things that don’t normally mix, to mix to form an emulsion.
An emulsion is a liquid that contains two (or more) ingredients that wouldn’t normally mix. Just like two squabbling reality TV stars, oil and water are examples of two things that don’t mix well and normally stay well apart. Emulsifier meaning in skincare is exactly the same.
If oil and water are present in the same liquid, without an emulsifier, they will normally separate out into two distinct layers. If the liquid is shaken, they will mix temporarily, causing small but visible droplets in the mixture before eventually separating out again.
If you think back to school chemistry lessons, you may remember diagrams or models of chains of different atoms joining together to make a molecule. Usually, a molecule of a water based substance will have both ends of its chain representing water. The same goes for a molecule of an oil based substance - both ends of its chain will represent oil.
But an emulsifier is unique in that it has one water soluble end and one oil soluble end. This unique property means that an emulsifier can bring together water based ingredients and oil based ingredients and allow them to permanently mix without the need for shaking or stirring. (Sorry, 007.)
Skincare products that contain both water and oil based ingredients (as many of them do) are great examples of emulsions that contain emulsifiers to help make them easier to apply and more appealing to the eye. So, the meaning of emulsifier in skincare is twofold - application and appearance.
Emulsifiers are also now being used to help deliver certain ingredients such as vitamins and antioxidants deeper into the skin's layers.
Cow’s milk is an example of an emulsion, since it contains both water and fats and a natural emulsifier to keep the liquid intact. Mayonnaise is another example, but since mayo is man made, it needs a little help on the emulsifier front.
In this case, the emulsifier is a product called lecithin that’s present in egg yolks. When eggs are used to make mayonnaise, the lecithin works to bind together the water based and oil based components.
On the other hand, if you’ve ever made a salad dressing using balsamic vinegar and olive oil, you’ll know that even after some vigorous whisking, the two will not mix together since there is no emulsifier present.
So you can see that emulsifiers are present in nature and have an important role in both skincare products and the things we eat and drink.
What Are the Common Emulsifiers in Skincare?
Not all emulsifiers in skincare are the same - there are three distinct types. All three have the same basic structure, similar to that of a detergent. But the three different types of emulsifiers have different electrical charges (on a chemistry level, they don't give us electric shocks!)
The three main examples of emulsifiers in skincare are - anionic emulsifiers, cationic emulsifiers and non-ionic emulsifiers.
Anionic emulsifiers
Anionic emulsifiers have a negative charge and are also capable of the most irritation to the skin. The most common anionic emulsifier in skincare is sodium lauryl sulphate, or SLS. It helps skincare formulations foam up or spread more easily on the skin, and is a well-known skin irritant.
Cationic emulsifiers
Cationic emulsifiers have a positive charge and can bind to the protein keratin in the skin, causing irritation (but possibly not as much as an emulsifier such as SLS can). Examples of cationic emulsifiers in skincare include benzalkonium chloride and behentrimonium methosulphate.
Non-ionic emulsifiers
Non-ionic emulsifiers have a neutral, or no charge and are therefore less irritating on the skin. Examples of nonionic emulsifiers in skincare include cetearyl alcohol, stearic acid and glyceryl stearate.
Are Emulsifiers the Same as Surfactants?
For some people, emulsifiers in skin care products are not beneficial. This is because emulsifiers work in the same way as a surfactant.
A surfactant, chemically speaking, has a water soluble end and an oil soluble end, and binds together water based molecules and oil based molecules to make an emulsion.
Emollients tend to be used more often in moisturising skin care products such as creams and lotions, and surfactants tend to be more common in cleansing products such facial washes and shampoos.
Surfactants are perhaps better known to us as the general population than emulsifiers. This is because a detergent is a form of surfactant.
That is, a detergent is a cleansing solution (for either the face, body or the kitchen worktop or toilet) that contains a surfactant.
This is what makes detergents and soaps effective at cleansing away dirt and oil from the skin. The surfactants help to attract water to our skin (the chemistry of water is such that it would prefer to hang out in groups of other water molecules in large blobs rather than stick uniformly to our skin). They also attract oily dirt that we can then rinse away from our skin. So, they’re really important in skin care.
In a way, emulsifiers, surfactants and detergents are pretty much the same thing. (Unless you’re a chemist, in which case, you’ll understand more of the subtle differences than we do.)
Are Surfactants and Emulsifiers Bad for the Skin?
In the main, surfactants and emulsifiers in skincare products are well tolerated by many of us. But for some of us, particularly those of us with stressed out, acne prone or sensitive skin, they can spell bad news. They can cause irritation and inflammation and mean that skin conditions such as acne, rosacea and psoriasis become worse.
This is because as well as blending ingredients, allowing ingredients and water to ‘stick’ to the skin and attracting dirt, surfactants and emulsifiers can disrupt the delicate skin barrier.
They can ‘wash out’ the skin of its own protective lipids (types of oils and fats) when the skin comes into contact with them and water. If our skin’s natural barriers are already compromised, such as in the case of having psoriasis, surfactants and emulsifiers in skincare can make matters worse causing redness, itching, irritation and heat in the skin.
Types of emulsifiers commonly used in skin care products include sodium lauryl sulphate (SLS), benzalkonium chloride, behentrimonium methosulphate, cetearyl alcohol, stearic acid, glyceryl stearate and ceteareth-20. But some are better tolerated than others.
In our pioneering range of alkalising skin care products, designed for acne prone, stressed out or contrary skin types, we’ve used emulsifiers such as glyceryl stearate and cetearyl alcohol as they've been developed as low irritation emulsifiers.
So if your current skin care range is causing your skin to become red, hot, irritated or angry, then why not give us a go? We promise you’ll love us!
Sources:
https://www.paulaschoice.com/ingredient-dictionary/thickeners%2Femulsifiers/emulsifier.html
https://www.schoolofnaturalskincare.com/natural-organic-emulsifiers-cosmetics/