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HiroTokyo Sakura Koji Face Mask

Sakura Koji Face Mask

Whitening & soothing mask sheet.
Uploaded by: nichatom on

HiroTokyo Sakura Koji Face 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. 

What-it-does: moisturizer/humectant, solvent | 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.

What-it-does: solvent

A clear, colorless liquid that works as a solvent and viscosity decreasing ingredient. It also has great skin-moisturizing abilities. 

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 >>

We don't have description for this ingredient yet.

We don't have description for this ingredient yet.

What-it-does: moisturizer/humectant

Soluble Collagen refers to the big, natural collagen molecules mostly extracted from fish or bovine skin. Spotting collagen on the ingredient list, you might think that, aha, this must be there to supplement the collagen content of our own skin, but you have to know that collagen is a huge-huge molecule that cannot absorb to the middle layer of the skin where collagen is and even if it could, it cannot just magically go the right places to become part of the skin's own collagen network. Putting collagen on your skin for anti-aging purposes is like throwing tent poles onto a ramshackle tent and expecting the tent to magically become nice and firm again. 

The strong point of collagen is being a large molecule with tremendous water binding capacity, i.e. an amazing humectant and moisturizer. It produces a water-rich film on the skin giving the stratum corneum (the uppermost layer of the skin) great hydration, making it nice and smooth and reducing trans-epidermal-water loss (the process of water evaporating out of your skin). 

Alpha-Arbutin - goodie
What-it-does: antioxidant, skin brightening

An optical isomer of naturally occurring arbutin (or beta-arbutin). Just like its sibling, alpha-arbutin is also a skin-brightening, depigmenting agent.

Researching the difference between the two kinds of arbutin, you can read in multiple places on the internet that alpha-arbutin is stronger in effect. Unfortunately, it's never backed up with a credible source. :(  Our own research resulted in conflicting results: a study from 1995 found that alpha-arbutin is 10x as effective on mouse melanoma as beta-arbutin. On the other hand, a more recent study from 2015 found that beta-arbutin is more effective both on mouse melanoma cells and on human melanoma cells (btw, kojic acid was the most effective on human melanoma cells).  

Also-called: Form of Vitamin C, MAP | What-it-does: skin brightening, antioxidant

A form of skincare superstar, Vitamin C. If you do not know, what the big deal about Vitamin C is, click here and read all about it, we will wait here for you. 

So now you know that pure vitamin C (aka ascorbic acid, AA) is really unstable and hard to formulate so the cosmetics industry is coming up with a bunch of derivatives to solve the problem and Magnesium Ascorbyl Phosphate (or MAP) is one of them.  

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". 

Also-called: Aloe Leaf Extract | What-it-does: soothing, emollient, moisturizer/humectant

The extract coming from the juice containing leaves of the Aloe vera plant. It's usually a hydroglycolic extract (though  oil extract for the lipid parts also exists) that has similar moisturizing, emollient and anti-inflammatory properties as the juice itself. We have written some more about aloe here.

We don't have description for this ingredient yet.

We don't have description for this ingredient yet.

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.

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). 

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. 

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
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 solvent
A clear, colorless liquid that works as a solvent and viscosity decreasing ingredient. It also has great skin-moisturizing abilities.  [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 moisturizer/humectant
Soluble Collagen refers to the big, natural collagen molecules mostly extracted from fish or bovine skin. Spotting collagen on the ingredient list, you might think that, aha, this must be there to supplement the collagen content of our own skin, but you have to know that collagen is a huge-huge molecule  [more]
what‑it‑does antioxidant | skin brightening
An optical isomer of naturally occurring arbutin (or beta-arbutin). Just like its sibling, alpha-arbutin is also a skin-brightening, depigmenting agent. [more]
what‑it‑does skin brightening | antioxidant
A form of skincare superstar, Vitamin C - it has proven skin-brightening abilities (in-vivo) and it might be able to boost collagen production as well (in-vitro). [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 soothing | emollient | moisturizer/humectant
The extract coming from the juice containing leaves of the Aloe vera plant with moisturizing, emollient and anti-inflammatory properties. [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
A super commonly used thickener and emulsion stabilizer. [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]