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Kose Skin Rhythm Moisty Dense Gel

Skin Rhythm Moisty Dense Gel

Melting gel penetrates deep into the stratum corneum while sleeping, to make skin soft without noticeable fine lines.
Uploaded by: decembermagpie on

Kose Skin Rhythm Moisty Dense Gel
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, 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.

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 >>

Ethanol - icky
Also-called: Alcohol | What-it-does: antimicrobial/antibacterial, solvent, viscosity controlling, astringent

Simply alcohol refers to ethanol and it's a pretty controversial ingredient. It has many instant benefits: it's a great solvent, penetration enhancer, creates cosmetically elegant, light formulas, great astringent and antimicrobial. No wonder it's popular in toners and oily skin formulas. 

The downside is that it can be very drying if it's in the first few ingredients on an ingredient list. 

What-it-does: emollient

An odorless and colorless emollient ester (cetyl alcohol + ethylhexanoic acid) that gives a velvety and silky feel to the skin. It has great spreadability and a non-oily feel. It's a popular ingredient in makeup removers.

What-it-does: emollient | Irritancy: 0 | Comedogenicity: 1

Probably the most common silicone of all. It is a polymer (created from repeating subunits) molecule and has different molecular weight and thus different viscosity versions from water-light to thick liquid.

As for skincare, it makes the skin silky smooth, creates a subtle gloss and forms a protective barrier (aka occlusive). Also, works well to fill in fine lines and wrinkles and give skin a plump look (of course that is only temporary, but still, it's nice). There are also scar treatment gels out there using dimethicone as their base ingredient. It helps to soften scars and increase their elasticity. 

What-it-does: emollient, emulsifying

It's the chemically chopped up version of normal lecithin. Most often it's used to create liposomes and to coat and stabilize other ingredients. 

We don't have description for this ingredient yet.

An amino acid sugar that can be found in the skin and does there good and important things. One of them is that it's a precursor for the biosynthesis of superstar moisturizer, hyaluronic acid. So acetyl glucosamine itself is also an important skin-identical ingredient and natural moisturizing factor.

But that is not all, acetyl glucosamine has two other great properties proved by double-blind clinical trials. First, it's a promising ingredient against wrinkles:  2% can improve wrinkles, particularly in the eye area.

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

Also-called: True Ginseng, Ginseng, Korean Ginseng;Panax Ginseng Root Extract | What-it-does: antioxidant, emollient

A  traditional Korean medicine used for more than 2000 years. Regarding skin care, its main thing seems to be enhancing skin nutrition and metabolism as a result of improving blood circulation.

It also contains biologically active components referred to as ginseng saponins (ginsenosides) that have potent antioxidant properties

This ingredient name is not according to the INCI-standard. :( What, why?!

Ceramide 2 - goodie
Also-called: Ceramide NG | What-it-does: skin-identical ingredient

One of the 9 types of ceramides that can be found naturally in the upper layer of the skin. Ceramides make up a big part (about 50%) of the goopy stuff that's between our skin cells (called extracellular matrix) and play a super important role in having a healthy skin barrier and keeping the skin hydrated

We wrote way more about ceramides at ceramide 1, so click here to know more.

Tocopherol - goodie
Also-called: Vitamin E | What-it-does: antioxidant | Irritancy: 0-3 | Comedogenicity: 0-3
  • Primary fat-soluble antioxidant in our skin
  • Significant photoprotection against UVB rays
  • Vit C + Vit E work in synergy and provide great photoprotection
  • Has emollient properties
  • Easy to formulate, stable and relatively inexpensive
Read all the geeky details about Tocopherol here >>

We don't have description for this ingredient yet.

The chemically chopped up version of the big protein molecule, collagen. It is often derived from fish or bovine sources and works as a nice moisturizer and humectant that helps the skin to hold onto water.  

To understand a bit more what Hydrolyzed Collagen is, you have to know that proteins are large chains of amino acids connected with so-called peptide bonds. These bonds can be broken up when a water molecule is added and the resulting thing is a mix of shorter length amino acids, also called peptides. So Hydrolyzed Collagen is not really collagen, it is rather an undefined and varying mix of largish peptides. Based on a manufacturer's data, the whole, soluble collagen has an average molecular weight of 300 000 Da, while this chopped up mixture has an average MW of 12 000 Da (still pretty big). 

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). 

What-it-does: chelating

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.

It is typically used in tiny amounts, around 0.1% or less.

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

We don't have description for this ingredient yet.

Also-called: Poly Vinyl Pyrollidone | What-it-does: viscosity controlling, emulsion stabilising | Irritancy: 0 | Comedogenicity: 0

These three letters stand for Poly Vinyl Pyrollidone, a big molecule created from repeated units of Vinyl Pyrrolidone, aka VP. Its main thing is being an important film former. It was the first synthetic polymer introduced as a hair fixative in the 1950s instead of insect-derived Shellac. 

So PVP likes to attach itself to surfaces such as the hair and the skin and forms a nice, thin, even film there. The film is useful for holding a hairstyle or extending the wear of color cosmetics and sunscreens. The disadvantage of PVP is that the film is a bit brittle and that PVP loves water (hygroscopic) that tends to destroy the film. This is the reason why hair styled with a PVP based product loses its style in high humidity. To fix this problem, there are now several versions of VP containing film formers that are less sensitive to humidity, for example, the molecule called VP/VA Copolymer

Also-called: Algin | What-it-does: viscosity controlling | Irritancy: 4 | Comedogenicity: 4

A large sugar molecule (aka polysaccharide) that's used as a gelling agent and comes from brown seaweed. 

Combined with calcium salts, it forms a rigid gel used in "rubber masks". 

A liquid fatty acid created from oleic acid. It's claimed to have great odour, thermal and oxidation stability and is great for  the stabilization of pigments and mineral particles in oils and solvents. It's quite popular in foundations.

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.

Cholesterol - goodie
What-it-does: skin-identical ingredient, emollient | Irritancy: 0 | Comedogenicity: 0

It's one of the important lipids that can be found naturally in the outer layer of the skin. About 25% of the goopy stuff between our skin cells consists of cholesterol. Together with ceramides and fatty acids, they play a vital role in having a healthy skin barrier and keeping the skin hydrated. 

Apart from being an important skin-identical ingredient, it's also an emollient and stabilizer

Also-called: lye | What-it-does: buffering

The unfancy name for it is lye. It’s a solid white stuff that’s very alkaline and used in small amounts to adjust the pH of the product and make it just right. 

For example, in case of AHA or BHA exfoliants, the right pH is super-duper important, and pH adjusters like sodium hydroxide are needed.  

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. 

What-it-does: preservative | Irritancy: 0 | Comedogenicity: 0

The most common type of feared-by-everyone-mostly-without-scientific-reason parabens. It's a cheap, effective and well-tolerated ingredient to make sure the cosmetic formula does not go wrong too soon

Apart from the general controversy around parabens (we wrote about it more here), there is a 2006 in-vitro (made in the lab not on real people) research about methylparaben (MP) showing that when exposed to sunlight, MP treated skin cells suffered more harm than non-MP treated skin cells. The study was not done with real people on real skin but still - using a good sunscreen next to MP containing products is a good idea. (Well, in fact using a sunscreen is always a good idea. :))

Perfume - 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.  

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 antimicrobial/antibacterial | solvent | viscosity controlling
Simple alcohol that's a great solvent, penetration enhancer, creates cosmetically elegant, light formulas, great astringent, and antimicrobial. In large amount can be very drying. [more]
what‑it‑does emollient
An odorless and colorless emollient ester that gives a velvety and silky feel to the skin. [more]
what‑it‑does emollient
irritancy, com. 0, 1
A very common silicone that gives both skin and hair a silky smooth feel. It also forms a protective barrier on the skin and fills in fine lines. Also used for scar treatment. [more]
what‑it‑does emollient | emulsifying
It's the chemically chopped up version of normal lecithin. Most often it's used to create liposomes and to coat and stabilize some other ingredient. 
what‑it‑does skin-identical ingredient | skin brightening
An amino sugar that helps the skin to stay hydrated, is also promising against wrinkles and can help to fade brown spots particularly when combined with niacinamide. [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 antioxidant | emollient
Ginseng - A traditional Korean medicine that has antioxidant properties, and is known to improve blood circulation. [more]
what‑it‑does skin-identical ingredient
One of the 9 types of ceramides that can be found naturally in the upper layer of the skin. Ceramides make up a big part (about 50%) of the goopy stuff that's between our skin cells (called extracellular matrix) and play a super important role in having a healthy skin barrier and keeping the skin hydrated.  [more]
what‑it‑does antioxidant
irritancy, com. 0-3, 0-3
Pure Vitamin E. Great antioxidant that gives significant photoprotection against UVB rays. Works in synergy with Vitamin C. [more]
what‑it‑does emollient | moisturizer/humectant
The chemically chopped up version of the big protein molecule, collagen. It is often derived from fish or bovine sources and works as a nice moisturizer and humectant that helps the skin to hold onto water.   To understand a bit more what Hydrolyzed Collagen is, you have to know that proteins are large chains of amino acids connected with so-called peptide bonds. [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 chelating
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 solvent
irritancy, com. 0, 1
what‑it‑does viscosity controlling
irritancy, com. 0, 0
These three letters stand for Poly Vinyl Pyrollidone, a big molecule created from repeated units of Vinyl Pyrrolidone, aka VP. Its main thing is being an important film former. [more]
what‑it‑does viscosity controlling
irritancy, com. 4, 4
A large sugar molecule (aka polysaccharide) that's used as a gelling agent and comes from brown seaweed. Combined with calcium salts, it forms a rigid gel used in "rubber masks".  [more]
what‑it‑does surfactant/cleansing | emulsifying
A liquid fatty acid with great odour, thermal and oxidation stability. It's great for the stabilization of pigments and mineral particles in oils and solvents. [more]
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 skin-identical ingredient | emollient
irritancy, com. 0, 0
It's one of the important lipids that can be found naturally in the outer layer of the skin. About 25% of the goopy stuff between our skin cells consists of cholesterol. [more]
what‑it‑does buffering
Lye - A solid white stuff that’s very alkaline and used in small amount to adjust the pH of the product.  [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 preservative
irritancy, com. 0, 0
The most common type of feared-by-everyone-mostly-without-scientific-reason parabens. It's a cheap, effective and well-tolerated ingredient to make sure the cosmetic formula does not go wrong too soon.  Apart from the general controversy around parabens (we wrote about it more here), there is a 2006 in-vitro (made in the lab not on real people) research about methylparaben (MP) sho [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]