cosmetic chemistry 101
What is cosmetic chemistry?
From my perspective, cosmetic chemistry is the wonderful medium of beauty & science together. It’s where beauty & science meets.
Cosmetic chemistry is the science that deals with the mixture and combination of substances to create cosmetics and how this combination interacts with us during its use – say, when you apply it to your skin, hair, nails, etc.
Simply put, it’s the science that goes behind creating a cosmetic ingredient and/or cosmetic product.
To create a cosmetic product, you need to understand the interactions occurring in your formula to have a stable product. You're working with chemicals that need to work together to be stable -- dun, dun, dun.
That’s right folks, you heard it here first. Cosmetic products are made with chemicals.
You also need to ensure that the product is safe for use – e.g. microbial testing, toxicological data, irritation tests, efficacy tests.
Basics in cosmetic chemistry
Surfactants — surface active agent that reduces the surface tension of a liquid in which it is dissolved in
functions can include : cleansing, emulsifying, foam boosting
examples include : sodium lauryl sulfate (SLS), cocamidopropyl betaine, sodium c14-16 olefin sulfonate
Emulsifiers - stabilizes 2 or more non-soluble or non-miscible substances
Polymers - substance that has a molecular structure consisting of a large number of similar units bonded together
functions can include : film-forming, rheological modification
Silicones - (…—Si—I—Si—O—Si—O—…)
one of the most misunderstood ingredients & one of my favorites for added sensorial aesthetics and function
the term “silicones” is one term that describes a broad category because there are a number of silicones to choose from in cosmetics
functions can include : conditioning, de-foaming, slip agent
examples include : dimethicone, cyclopentasiloxane
Preservatives — inhibit the development of micro-organisms
this is exactly why a product should have a preservation system. Without it, the product will be more susceptible to microbial contamination, which would not be safe for use.
some products use the “hurdle” method but that is a topic for later.
pH adjusters - ingredients used to adjust the pH of cosmetics
use a base to increase the pH
examples include : sodium hydroxide, AMP, arginine
use an acid to decrease the pH
examples include : citric acid, lactic acid, glycolic acid
So… what is a cosmetic then?
When consumers think about cosmetic products, they tend to think of:
makeup, skincare, hair care, body care, nail care
As a consumer myself, these are the first things that I think of, as well. Hence, why I mentioned them. Of course, there may be other categories of products that you may think of.
On the other hand, as a cosmetic chemist, I familiarize myself with the FDA’s cosmetic definition.
The definition covers any and all cosmetics that you can possibly think of. If you can apply the product onto yourself in any of the above forms to cleanse, beautify (Google definition of beautify: improve the appearance of), promote attractiveness, or alter the appearance, it's probably a cosmetic.
This definition does not cover soaps or products that have drug claims (e.g. anti-dandruff shampoo, antimicrobial soaps, deodorants that are also antiperspirants).
I also familiarize myself with the EU cosmetic definition to begin understanding the thought process behind the EU market and become more helpful to EU customers/brands.
I like how the EU definition includes teeth and mucous membranes of the oral cavity because you may neglect that oral care products are cosmetics -- again, this does not include products that have drug-related claims. If you'd like a quick overview about drug claims versus cosmetic claims, please let me know.
Although this is a very brief introductory to cosmetic chemistry, I encourage those interested in this topic to continue to read our posts and to follow us on Instagram (@cosmeticpadacts) & Twitter for updates on upcoming posts.