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All about Surfactants (formulating for beginners)

Updated: May 13, 2022


Surfactants are the most important ingredients found in cosmetics. They help achieve what the product is trying to do. You may not understand surfactants fully when you first start learning about them, but thats okay, they're confusing. With experimenting and patience it will all make sense.


What are Surfactants

Surfactants, short for "surface active agents" can do a variety of things for cosmetics. They are emulsifiers, cleansers, foaming agents, thickeners, solubilizers, wetting agents, and more.


An emulsifier is an ingredient that blends oil and water together. A solubilizer helps make an ingredient soluble in a solution that it may not be soluble in. For example it can solubilize a small amount of oil, like 1-5%, into some water. A wetting agent helps increase spreadability.

Surfactants are the most important ingredients in a skincare product because they help achieve the products purpose. There are 4 different kinds of surfactants; Anionic, Amphoteric, Nonionic, and Cationic. Each of these surfactants are used in a variety of different products and are very important to understand. The surfactant you decide to use in your product heavily depends on what your products purpose is and what the product is trying to achieve.

Anionic Surfactants

This type of surfactant has negatively charged ions. Anionic surfactants are most commonly used as the primary cleansing agent in products like; face washes, body wash, shampoos, typically any type of product that cleanses and foams. This is because anionic surfactants are great cleansing agents. They help lift and suspend oils and dirt from the skin.

Anionic surfactants are typically more harsh on the skin, which can cause irritation, and this is why they are often combined with nonionic or amphoteric surfactants that also cleanse and foam. Combining anionic surfactants with either nonionic surfactants or amphoteric surfactants can help reduce irritation or even help increase lather and foam. Even though anionic surfactants can be irritating the reason why people use them as the main surfactant in cleansing products is because they are the best kind of foaming agents, they cleanse the best, and they tend to be the cheapest.


Even though most anionic surfactants are cleansing agents there are some that aren't cleansing agents. Some can work as emulsifiers. For example; Ritamulse SCG

Nowadays there are lots of anionic surfactants that lather, foam and cleanse that aren't as irritating though. For example; foaming apple, foaming oats, and foaming soy. These are all anionic surfactants, but they aren't as irritation and they don't lather as well as an anionic surfactant like SLS.

Amphoteric Surfactants

Amphoteric surfactants can have either a positive or negative charge, depending on the PH. In acidic solutions they become positively charged and in alkaline solutions they have a negative charge.


They are more mild and gentle than anionic surfactants. They are, most commonly used is cleansing products like shampoos, body washes, and face washes. Amphoteric surfactants can help make anionic surfactants less irritating on the skin. They can even enhance lather by making bubbles smaller and feel creamier.

Amphoteric surfactants are much more mild and gentle on the skin, which is great, but unfortunately they don't produce as much lather as anionic surfactants do. So they aren't as good to use on their own for products like shampoos and bubble baths. They are also more expensive than anionic surfactants which is another reason why anionic and amphoteric surfactants are commonly used together.



Nonionic Surfactants

Nonionic surfactants have no charge. Nonionic surfactants are most commonly used as emulsifiers and solubilizers in cosmetics. They work great at preventing the separation of water and oil.


There are also some nonionic surfactants that lather, foam, and cleans. The reason they aren't typically used as the primary surfactant in cleansing products is because they don't lather up and cleanse as well as anionic surfactants or even amphoteric surfactants. They are more gentle on the skin though, which is why they are commonly used in baby products and facial cleansers.


It is very common to pair anionic surfactants with nonionic surfactants to reduce the harshness from anionic surfactants.


There are some nonionic surfactants that cleanse and foam, but also help solublize oil into water. For example, coco glucoside or decyl glucoside. They both are gentle, have a mild lather, and can solubilize roughly 1-3% oil into water.


Examples of nonionic Foaming Agents; coco glucoside & decyl glucoside

Cationic Surfactants

Cationic surfactants are positively charged. Cationic surfactants help condition, soften and some even emulsify oil and water. Cationic surfactants are commonly used as the primary ingredient in hair conditioners to condition detangle and soften the hair. Since the hair has a slight negative charge when wet, the cationic ingredient sticks to the surface of the hair by static attraction. The positively charged cationic surfactant is attracted to the negatively charged wet hair. The conditioner is therefore difficult to remove from the hair, so it smoothes the hair and coats it, making it easier to comb.


Some cationic ingredients even act like emulsifiers and can be used as the primary ingredient in moisturizers to blend water and oil together and will also help soften and condition the skin.


Examples of cationic surfactants - BTMS 50, varisoft EQ 65, ICE hair restore, creammaker CAT, ICE conditioner


How do you know which surfactant you need?

Whenever you go to make a new product one of the first things you need to decide is what surfactants you need and which you want to use. This process becomes a lot easier as you learn about more ingredients.


If you are making a cleansing product like a face wash, body wash, shampoo, or bubble bath then you know that you need a cleansing surfactant. But which type do you reach for? Anionic, Nonionic, or Amphoteric? Well if you are making something where you want lots of lather and big bubbles such as a bubble bath or shampoo then you want to reach for an anionic surfactant and pair it with an amphoteric surfactant. Nonionic could work too, but I normally use an anionic with amphoteric in bubble baths and shampoos. I find that amphoteric surfactants lather more than nonionic.


As for body washes, you may not need as big of bubbles as a bubble bath or shampoo, but you still want a good lather, so I recommend an anionic surfactant with either a nonionic or amphoteric surfactant.


A face wash may depend on the skin type. If you have dry skin then using just a nonionic surfactant could work or an amphoteric paired with a nonionic. If you have oily skin and you like that squeeky clean feeling, then you may want to use an anionic surfactant with an amphoteric or nonionic. I mentioned earlier that there are some, more mild anionic surfactants like foaming apple. I personally don't find that this ingredient gives that squeeky clean feeling, but rather a gentle more hydrating cleanse you would find from a nonionic or amphoteric surfactant. So do keep this in mind. It is important to experiment with different surfactants so you know how they work and which you prefer using. With science continuously progressing we get more and more innovating ingredients all the time.

So as you can see the main purpose of a face wash, body wash, or shampoo, is to lather and cleanse. So without surfactants you wouldn't even be able to make any of these products. Which goes to show that the main thing you need to make these products are surfactants.

Say, you want to make a moisturizer. Moisturizers are water and oil emulsified together using an emulsifier. So if you are making a moisturizer you know you need some kind of emulsifier. Which most commonly are nonionic surfactants, although there are some anionic and cationic emulsifiers as well. (I know it's confusing, but I promise with time and practice it will all start to make sense.)


Other things to mention;

Anionic and Cationic surfactants can't be combined. Since Cationic are positively charged and Anionic is negatively charged they can not be used together. This will cause a failed formula. Although, there are a few exceptions to this rule. Some cationic surfactants are specifically made to work with anionic surfactants. For example Honeyquat is a cationic surfactant, but it has been designed to work with anionic surfactants. You can typically find this out, by reading the formulating guidelines of said ingredient.


Examples of cationic surfactants that are okay to use with anionic surfactants - honeyquat, hydrolyzed proteins, polyquaternium-78

Tips on understanding more about surfactants;

I advise going onto either formulatorsampleshop.com or lotioncrafter.com and looking through their ingredients. Click on emulsifiers, read and learn about each of the emulsifiers, see if they are nonionic, cationic, amphoteric or anionic. Click on the surfactants read about each of those, click on solubilizers read about those. I'm asked all the time "how did you learn so much about different ingredients" I literally just read about them on these websites. Obviously we all don't have the time or brain powder to read about all the ingredients, but click on the ones that sound familiar to you or spark your interest. Grab a notebook and write down everything you read that stands out to you or seems important. Writing notes is the best way to learn as it helps you absorb the information better. You are less likely to understand something if you just read it. Write it down, then when you go to experiment you can refer back to your notes.


There has been so many times when I've been trying to learn about something, but I just don't understand it, so I take notes. I still may not understand it fully even after taking notes, but after doing experiments and rereading my notes the information starts to make sense. Formulating isn't easy. If it was, then everyone would be doing it. I remember when I first learned about surfactants, I did not understand them at all, even after taking notes on the subject. But over time and with lots of experimenting I started to understand surfactants more and more over time.

Surfactants recommended for products

(This is just a general idea on what surfactant to use in each product. Of course this isn't what is required, it's just a general idea)

Face Washes - Anionic Amphoteric or Nonionic

Body washes - Anionic Amphoteric or Nonionic

Shampoos - Anionic & Amphoteric

Bubble bath - Anionic & Amphoteric

Hair Conditioners - Cationic

Moisturizers/Lotions/Creams - Cationic Nonionic or Anionic





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