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KOCOSTAR Watermelon Slice Mask

Watermelon Slice Mask

Contains 10,000ppm of watermelon extract, which is rich in moisture. Not only does it moisturize, it calms the skin.
Uploaded by: bluemaskwithcat on

KOCOSTAR Watermelon Slice Mask
Ingredients explained

Also-called: Aqua | What-it-does: solvent

Good old water, aka H2O. The most common skincare ingredient of all. You can usually find it right in the very first spot of the ingredient list, meaning it’s the biggest thing out of all the stuff that makes up the product. 

It’s mainly a solvent for ingredients that do not like to dissolve in oils but rather in water. 

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Once inside the skin, it hydrates, but not from the outside - putting pure water on the skin (hello long baths!) is drying. 

One more thing: the water used in cosmetics is purified and deionized (it means that almost all of the mineral ions inside it is removed). Like this, the products can stay more stable over time. 

What-it-does: moisturizer/humectant, solvent, viscosity controlling | Irritancy: 0 | Comedogenicity: 1

Butylene glycol, or let’s just call it BG, is a multi-tasking colorless, syrupy liquid. It’s a great pick for creating a nice feeling product.  

BG’s main job is usually to be a solvent for the other ingredients. Other tasks include helping the product to absorb faster and deeper into the skin (penetration enhancer), making the product spread nicely over the skin (slip agent), and attracting water (humectant) into the skin.

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It’s an ingredient whose safety hasn’t been questioned so far by anyone (at least not that we know about). BG is approved by Ecocert and is also used enthusiastically in natural products. BTW, it’s also a food additive. 

Glycerin - superstar
Also-called: Glycerol | What-it-does: skin-identical ingredient, moisturizer/humectant | Irritancy: 0 | Comedogenicity: 0
  • A natural moisturizer that’s also in our skin
  • A super common, safe, effective and cheap molecule used for more than 50 years
  • Not only a simple moisturizer but knows much more: keeps the skin lipids between our skin cells in a healthy (liquid crystal) state, protects against irritation, helps to restore barrier
  • Effective from as low as 3% with even more benefits at higher concentrations up to 20-40% (around 10% is a good usability-effectiveness sweet spot)
  • High-glycerin moisturizers are awesome for treating severely dry skin
Read all the geeky details about Glycerin here >>

What-it-does: emollient, solvent

A water-loving emollient and humectant that gives a nice skin feel and slip to the product. It works well with facial toners.

Also-called: Watermelon Fruit Extract | What-it-does: antioxidant

We love a cold slice of watermelon on a hot summer day and we love watermelon as a skincare ingredient. It's really full of good-for-the-skin stuff: it contains a bunch of vitamins (A, B, C and E), mineral salts (K, Mg, Ca and Fe), amino acids citrulline and arginine and antioxidant carotenoids and phenolics

It's especially rich in potent antioxidant, lycopene (a type of carotenoid), the cool pigment that's responsible for the red color of the watermelon. According to manufacturer info, in-vitro (made in the lab not on real people) studies show that watermelon extract gives significant DNA protection against UV damage. The in-vivo (made on real people) study also confirmed this and the watermelon formula showed 25% increase in skin protection compared to placebo.

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All in all, a cool fruit extract with potent antioxidant magic abilities.

What-it-does: skin-identical ingredient, moisturizer/humectant | Irritancy: 0 | Comedogenicity: 0

It’s the - sodium form - cousin of the famous NMFhyaluronic acid (HA). If HA does not tell you anything we have a super detailed, geeky explanation about it here.  The TL; DR version of HA is that it's a huge polymer (big molecule from repeated subunits) found in the skin that acts as a sponge helping the skin to hold onto water, being plump and elastic. HA is famous for its crazy water holding capacity as it can bind up to 1000 times its own weight in water.

As far as skincare goes, sodium hyaluronate and hyaluronic acid are pretty much the same and the two names are used interchangeably. As cosmetic chemist kindofstephen writes on reddit  "sodium hyaluronate disassociates into hyaluronic acid molecule and a sodium atom in solution". 

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In spite of this, if you search for "hyaluronic acid vs sodium hyaluronate" you will find on multiple places that sodium hyaluronate is smaller and can penetrate the skin better. Chemically, this is definitely not true, as the two forms are almost the same, both are polymers and the subunits can be repeated in both forms as much as you like. (We also checked Prospector for sodium hyaluronate versions actually used in cosmetic products and found that the most common molecular weight was 1.5-1.8 million Da that absolutely counts as high molecular weight).

What seems to be a true difference, though, is that the salt form is more stable, easier to formulate and cheaper so it pops up more often on the ingredient lists. 

If you wanna become a real HA-and-the-skin expert you can read way more about the topic at hyaluronic acid (including penetration-questions, differences between high and low molecular weight versions and a bunch of references to scientific literature).

Also-called: Acai Extract

We don't have description for this ingredient yet.

What-it-does: moisturizer/humectant

We don't have description for this ingredient yet.

Also-called: Purslane Extract | What-it-does: soothing, antioxidant

Portulaca Oleracea is a nice succulent with bright yellow flowers and edible nutritious vegetables. It's a famous plant in Korean traditional medicine to treat infection and irritated skin.

Modern research confirms that it's loaded with skin-goodies: it's the richest green plant source of omega-3 fatty acids (α-linolenic acid), contains NMFs (polysaccharides and amino acids),  vitamins (β-carotene), minerals, and antioxidants (yellow betaxanthins and reddish betacyanins). Thanks to all its beneficial components, Purslane Extract has several magic properties: it's a great anti-inflammatory and antioxidant agent and also has wound healing abilities

Betaine - goodie
What-it-does: moisturizer/humectant

A sugar beet derived amino acid derivative with nice skin protection and moisturization properties. Betain's special thing is being an osmolyte, a molecule that helps to control cell-water balance.  It is also a natural osmoprotectant, meaning that it attracts water away from the protein surface and thus protects them from denaturation and increases their thermodynamic stability. 

It also gives sensorial benefits to the formula and when used in cleansers, it helps to make them milder and gentler. 

It's one of the most commonly used thickeners and emulsion stabilizers. If the product is too runny, a little xanthan gum will make it more gel-like. Used alone, it can make the formula sticky and it is a good team player so it is usually combined with other thickeners and so-called rheology modifiers (helper ingredients that adjust the flow and thus the feel of the formula). The typical use level of Xantha Gum is below 1%, it is usually in the 0.1-0.5% range. 

Btw, Xanthan gum is all natural, a chain of sugar molecules (polysaccharide) produced from individual sugar molecules (glucose and sucrose) via fermentation. It’s approved by Ecocert and also used in the food industry (E415). 

A castor oil derived, white, lard-like helper ingredient that is used as a solubilizer to put fragrances (those are oil loving things) into water-based products such as toners.

What-it-does: viscosity controlling, emulsion stabilising | Irritancy: 0 | Comedogenicity: 1

A big molecule created from repeated subunits (a polymer of acrylic acid) that magically converts a liquid into a nice gel formula.  It usually has to be neutralized with a base (such as sodium hydroxide) for the thickening to occur and it creates viscous, clear gels that also feel nice and non-tacky on the skin. No wonder, it is a very popular and common ingredient. Typically used at 1% or less in most formulations.

Also-called: Guardiant, Glasswort Extract | What-it-does: antioxidant, skin brightening, moisturizer/humectant

A plant extract coming from glasswort, a type of succulent that grows in the salt marshes along the coastline of South Korea. According to its Korean manufacturer, it contains good-for-the-skin things like betaine, amino acids and minerals and the extract can strengthen the skin barrier, increase skin recovery and provide deep moisturization effect

There is also an in-vitro (not done on real people but in the lab) study from 2009 that shows promising antioxidant and skin whiting properties about the Salicornia Herbacea Extract and concludes that "it would be a good candidate for skin rejuvenating agent".

We don't have description for this ingredient yet.

We don't have description for this ingredient yet.

We don't have description for this ingredient yet.

What-it-does: antioxidant

We don't have description for this ingredient yet.

Also-called: Soybean Extract | What-it-does: antioxidant, skin brightening, soothing, emollient

When you hear the word Soy, you probably associate it with soy sauce or tofu, not skincare. But as it turns out, the soybean has a bunch of useful active components and soybean extract is an interesting cosmetic ingredient with a wide range of possible effects. 

Its main active components are antioxidant phenolic acids and flavonoids as well as small and large soy proteins. The large proteins give soybean extract nice skin smoothing and softening properties, while the small proteins (soybean trypsin inhibitor (STI) and Bowman-Birk inhibitor (BBI)) are thought to inhibit skin pigmentation and delay hair regrowth.   

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Regarding skin pigmentation, the soybean extract works by hindering melanosome transfer, meaning it blocks the melanin pigment from traveling up to the surface of the skin and becoming visible there. This is useful for most pigmentation situations but, if you have melasma, soy is not for you as melasma is estrogen-mediated and soy is a well-known phytoestrogen

The most famous and bioactive flavonoids in soybeans are the isoflavones called genistein and diadzein that have potent antioxidant and anti-inflammatory properties. Genistein is also proven to inhibit UV induced redness in human skin. These isoflavones are also the ones that make soy a phytoestrogen, meaning they have a (weak) estrogenic effect. Topical estrogen is known to decrease skin thinning and collagen loss and soy might be able to do the same, especially during and after menopause when natural estrogen levels run low.  

There is also some promising, but as yet not in-vivo (done on real people), research that soybean extract can stimulate both elastin and collagen synthesis and thus lead to healthier, younger-looking skin. 

Overall, soybean extract is a promising and multi-functional active, a nice addition to most ingredient lists.

We don't have description for this ingredient yet.

We don't have description for this ingredient yet.

What-it-does: solvent

A really multi-functional helper ingredient that can do several things in a skincare product: it can bring a soft and pleasant feel to the formula, it can act as a humectant and emollient, it can be a solvent for some other ingredients (for example it can help to stabilize perfumes in watery products) and it can also help to disperse pigments more evenly in makeup products. And that is still not all: it can also boost the antimicrobial activity of preservatives

It’s a handy multi-tasking ingredient that gives the skin a nice, soft feel. At the same time, it also boosts the effectiveness of other preservatives, such as the nowadays super commonly used phenoxyethanol

The blend of these two (caprylyl glycol + phenoxyethanol) is called Optiphen, which not only helps to keep your cosmetics free from nasty things for a long time but also gives a good feel to the finished product. It's a popular duo.

What-it-does: perfuming

We don't have description for this ingredient yet.

Allantoin - goodie
What-it-does: soothing | Irritancy: 0 | Comedogenicity: 0

Super common soothing ingredient. It can be found naturally in the roots & leaves of the comfrey plant, but more often than not what's in the cosmetic products is produced synthetically. 

It's not only soothing but it' also skin-softening and protecting and can promote wound healing.

Arginine - goodie

A semi-essential (infants cannot synthesize it, but adults can) amino acid that is one of the primary building blocks of hair keratin and skin collagen. It's a natural moisturizing factor, a skin hydrator and might also help to speed up wound healing

Arginine usually has a positive charge (cationic) that makes it substantive to skin and hair (those are more negatively charged surfaces) and an excellent film former.  Thanks to the positive charge, it also creates a complex with AHAs (AHAs like to lose a hydrogen ion and be negatively charged, so the positive and the negative ions attract each other) that causes a "time-release AHA effect" and reduces the irritation associated with AHAs

What-it-does: preservative

It’s pretty much the current IT-preservative. It’s safe and gentle, but even more importantly, it’s not a feared-by-everyone-mostly-without-scientific-reason paraben.

It’s not something new: it was introduced around 1950 and today it can be used up to 1% worldwide. It can be found in nature - in green tea - but the version used in cosmetics is synthetic. 

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Other than having a good safety profile and being quite gentle to the skin it has some other advantages too. It can be used in many types of formulations as it has great thermal stability (can be heated up to 85°C) and works on a wide range of pH levels (ph 3-10). 

It’s often used together with ethylhexylglycerin as it nicely improves the preservative activity of phenoxyethanol.

Super common little helper ingredient that helps products to remain nice and stable for a longer time. It does so by neutralizing the metal ions in the formula (that usually get into there from water) that would otherwise cause some not so nice changes.

Fragrance - icky
Also-called: Fragrance, Parfum;Parfum/Fragrance | What-it-does: perfuming

Exactly what it sounds: nice smelling stuff put into cosmetic products so that the end product also smells nice. Fragrance in the US and parfum in the EU is a generic term on the ingredient list that is made up of 30 to 50 chemicals on average (but it can have as much as 200 components!). 

If you are someone who likes to know what you put on your face then fragrance is not your best friend - there's no way to know what’s really in it.  

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Also, if your skin is sensitive, fragrance is again not your best friend. It’s the number one cause of contact allergy to cosmetics. It’s definitely a smart thing to avoid with sensitive skin (and fragrance of any type - natural is just as allergic as synthetic, if not worse!). 

You may also want to take a look at...

what‑it‑does solvent
Normal (well kind of - it's purified and deionized) water. Usually the main solvent in cosmetic products. [more]
what‑it‑does moisturizer/humectant | solvent | viscosity controlling
irritancy, com. 0, 1
An often used glycol that works as a solvent, humectant, penetration enhancer and also gives a good slip to the products. [more]
what‑it‑does skin-identical ingredient | moisturizer/humectant
irritancy, com. 0, 0
A real oldie but a goodie. Great natural moisturizer and skin-identical ingredient that plays an important role in skin hydration and general skin health. [more]
what‑it‑does emollient | solvent
A water-loving emollient and humectant that gives a nice skin feel and slip to the product. It works well with facial toners.
what‑it‑does antioxidant
Watermelon extract that's full of good-for-the-skin stuff, including vitamins, minerals, amino acids and antioxidants. A useful antioxidant-rich ingredient to protect skin from UV-induced damage. [more]
what‑it‑does skin-identical ingredient | moisturizer/humectant
irritancy, com. 0, 0
It's the salt form of famous humectant and natural moisturizing factor, hyaluronic acid. It can bind huge amounts of water and it's pretty much the current IT-moisturizer. [more]
what‑it‑does moisturizer/humectant
what‑it‑does soothing | antioxidant
Purslane Extract - a traditional Korean medicinal plant with skin-soothing, antioxidant and wound healing abilities. [more]
what‑it‑does moisturizer/humectant
A sugar beet derived amino acid derivative with nice skin protection and moisturization properties. Its special thing is being an osmolyte, a molecule that helps to control cell-water balance.  [more]
what‑it‑does viscosity controlling | emulsifying | surfactant/cleansing
A super commonly used thickener and emulsion stabilizer. [more]
what‑it‑does emulsifying | surfactant/cleansing
A castor oil derived, white, lard-like helper ingredient that is used as a solubilizer to put fragrances into water-based products such as toners.
what‑it‑does viscosity controlling
irritancy, com. 0, 1
A handy white powder that magically converts a liquid into a nice gel formula. [more]
what‑it‑does antioxidant | skin brightening | moisturizer/humectant
Glasswort Extract - A plant extract that's claimed to be able to strengthen the skin barrier and provide deep moisturization effect. It might also have antioxidant and skin whiting properties. [more]
what‑it‑does antioxidant
what‑it‑does antioxidant | skin brightening | soothing | emollient
When you hear the word Soy, you probably associate it with soy sauce or tofu, not skincare. But as it turns out, the soybean has a bunch of useful active components and soybean extract is an interesting cosmetic ingredient with a wide range of possible effects. Its main active components are antioxidant phenolic acids and flavonoids  [more]
what‑it‑does solvent
A multi-functional helper ingredient that acts as a humectant and emollient. It's also a solvent and can boost the effectiveness of preservatives. [more]
what‑it‑does moisturizer/humectant | emollient
A handy multi-tasking ingredient that gives the skin a nice, soft feel and also boosts the effectiveness of other preservatives. [more]
what‑it‑does perfuming
what‑it‑does soothing
irritancy, com. 0, 0
Super common soothing ingredient. It can be found naturally in the roots & leaves of the comfrey plant, but more often than not what's in the cosmetic products is produced synthetically. It's not only soothing but it' [more]
what‑it‑does skin-identical ingredient
An amino acid that is one of the primary building blocks of hair keratin and skin collagen. It's a natural moisturizing factor and might also help to speed up wound healing.  [more]
what‑it‑does preservative
Pretty much the current IT-preservative. It’s safe and gentle, and can be used up to 1% worldwide. [more]
what‑it‑does chelating | viscosity controlling
Super common little helper ingredient that helps products to remain nice and stable for a longer time. It does so by neutralizing the metal ions in the formula (that usually get into there from water) that would otherwise cause some not so nice changes. [more]
what‑it‑does perfuming
The generic term for nice smelling stuff put into cosmetic products so that the end product also smells nice. It is made up of 30 to 50 chemicals on average. [more]