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Kerastase Chronologiste Mask

Chronologiste Mask

Hair Mask
Uploaded by: skincare101 on

Skim through

Ingredient name what-it-does irr., com. ID-Rating
Aqua/Water/Eau solvent
Cetearyl Alcohol emollient, viscosity controlling, emulsifying, surfactant/​cleansing 1, 2
Amodimethicone emollient
Behentrimonium Chloride preservative
Cetyl Esters emollient
Isopropyl Alcohol solvent, viscosity controlling, perfuming 0, 0 icky
PEG/PPG/Polybutylene Glycol-8/5/3 Glycerin moisturizer/​humectant
Trideceth-6 emulsifying, surfactant/​cleansing
Bisabolol soothing goodie
Caprylyl Glycol moisturizer/​humectant, emollient
Benzoic Acid preservative
Tocopherol antioxidant 0-3, 0-3 goodie
Cetrimonium Chloride antimicrobial/​antibacterial, emulsifying, preservative, surfactant/​cleansing
Benzyl Salicylate perfuming icky
Hexyl Cinnamal perfuming icky
Benzyl Alcohol preservative, perfuming, solvent, viscosity controlling
Limonene perfuming, solvent icky
Butylene Glycol moisturizer/​humectant, solvent, viscosity controlling 0, 1
Sodium Hydroxide buffering
Citronellol perfuming icky
Farnesol perfuming icky
2-Oleamido-1,3-Octadecanediol
Geraniol perfuming icky
Sodium Hyaluronate skin-identical ingredient, moisturizer/​humectant 0, 0 goodie
Safflower Glucoside
Hydroxycitronellal perfuming icky
Octyldodecanol emollient, perfuming
Lecithin emollient, emulsifying goodie
Phenethyl Alcohol
Polycaprolactone
Phenoxyethanol preservative
Poloxamer 188 emulsifying, surfactant/​cleansing
Ceramide NP skin-identical ingredient goodie
Hydroxypalmitoyl Sphinganine skin-identical ingredient goodie
Alteromonas Ferment Extract soothing goodie
BHT antioxidant, preservative
Sodium Citrate chelating, buffering
Parfum/Fragrance perfuming icky

Kerastase Chronologiste Mask
Ingredients explained

Also-called: Aqua;Water | 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. 

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: emollient, viscosity controlling, emulsifying, emulsion stabilising, surfactant/cleansing | Irritancy: 1 | Comedogenicity: 2

An extremely common multitasker ingredient that gives your skin a nice soft feel (emollient) and gives body to creams and lotions. It also helps to stabilize oil-water mixes (emulsions), though it does not function as an emulsifier in itself. Its typical use level in most cream type formulas is 2-3%.  

It’s a so-called fatty alcohol, a mix of cetyl and stearyl alcohol, other two emollient fatty alcohols.  Though chemically speaking, it is alcohol (as in, it has an -OH group in its molecule), its properties are totally different from the properties of low molecular weight or drying alcohols such as denat. alcohol. Fatty alcohols have a long oil-soluble (and thus emollient) tail part that makes them absolutely non-drying and non-irritating and are totally ok for the skin.

What-it-does: emollient

A modified dimethicone-type silicone molecule that also contains amino-groups. Having amino-groups means that Amodimethicone also has Nitrogen in its molecule that likes to have a positive charge. Positively charged (or quaternised) molecules are substantive to skin and hair as those are negatively charged surfaces and are excellent film formers. Amodiemthcone is no exception and it is especially recommended for hair-care products for its long-lasting hair conditioning benefits.

What-it-does: preservative

We don't have description for this ingredient yet.

What-it-does: emollient

We don't have description for this ingredient yet.

What-it-does: solvent, viscosity controlling, perfuming | Irritancy: 0 | Comedogenicity: 0

We don't have description for this ingredient yet.

What-it-does: moisturizer/humectant

A glycerin derived, synthetic oily liquid that is also water soluble and works as a great skin moisturizer. Its moisturizing ability is comparable to glycerin itself and the two together work in synergy to give skin superb hydration. It is also "cosmetically elegant", i.e. non-sticky and non-greasy.

It can also work as a co-surfactant helping to dissolve small amounts of oily things (think essential oils or vitamin E) into water-based formulas.

We don't have description for this ingredient yet.

Bisabolol - goodie
Also-called: Alpha-Bisabolol | What-it-does: soothing

It's one of the active parts of Chamomile that contains about 30% of bisabolol. It's a clear oily fluid that is used in skincare as a nice anti-inflammatory and soothing ingredient. 

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: preservative

An Ecocert-approved, natural preservative that counts as gentle and non-irritating to the skin. Usually, it comes to the formula as part of a preservative blend as it's not enough on its own.

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.

What-it-does: perfuming

It’s a common fragrance ingredient that has a light floral smell.  It’s one of the “EU 26 fragrances” that has to be labelled separately (and cannot be simply included in the term “fragrance/perfume” on the label) because of allergen potential. Best to avoid if your skin is sensitive.

What-it-does: perfuming

A common fragrance ingredient that smells like jasmine. It is one of the “EU 26 fragrances” that has to be labelled separately because of allergen potential. Best to avoid if your skin is sensitive.

It's one of those things that help your cosmetics not to go wrong too soon, aka a preservative. It can be naturally found in fruits and teas but can also be made synthetically.

No matter the origin, in small amounts (up to 1%) it’s a nice, gentle preservative. Has to be combined with some other nice preservatives, like potassium sorbate to be broad spectrum enough.  

In high amounts, it can be a skin irritant, but don’t worry, it’s never used in high amounts.

Limonene - icky
What-it-does: perfuming, solvent, deodorant

A super common and cheap fragrance ingredient. It's in many plants, e.g. rosemary, eucalyptus, lavender, lemongrass, peppermint and it's the main component (about 50-90%) of the peel oil of citrus fruits.

It does smell nice but the problem is that it oxidizes on air exposure and the resulting stuff is not good for the skin. Oxidized limonene can cause allergic contact dermatitis and counts as a frequent skin sensitizer

Limonene's nr1 function is definitely being a fragrance component, but there are several studies showing that it's also a penetration enhancer, mainly for oil-loving components.

All in all, limonene has some pros and cons, but - especially if your skin is sensitive - the cons probably outweigh the pros.  

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.

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. 

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.  

BTW, lye is not something new. It was already used by ancient Egyptians to help oil and fat magically turn into something else. Can you guess what? Yes, it’s soap. It still often shows up in the ingredient list of soaps and other cleansers.

Sodium hydroxide in itself is a potent skin irritant, but once it's reacted (as it is usually in skin care products, like exfoliants) it is totally harmless.

What-it-does: perfuming

Citronellol is a very common fragrance ingredient with a nice rose-like odor. In the UK, it’s actually the third most often listed perfume on the ingredient lists. 

It can be naturally found in geranium oil (about 30%) or rose oil (about 25%). 

As with all fragrance ingredients, citronellol can also cause allergic contact dermatitis and should be avoided if you have perfume allergy. In a 2001 worldwide study with 178 people with known sensitization to fragrances citronellol tested positive in 5.6% of the cases.

There is no known anti-aging or positive skin benefits of the ingredient. It’s in our products to make it smell nice. 

Farnesol - icky
What-it-does: perfuming, deodorant

With a sweet, light and floral scent, Farnesol is a popular fragrancing ingredient to make your cosmetics that bit nicer to use. It starts its life as a colorless liquid that can either be synthetically created or extracted from loads of plants like citronella, neroli, ylang-ylang, and tuberose.

The reason we list it as icky is because Farnesol is one of the “EU 26 fragrances” that has to be labeled separately (and cannot be simply included in the term “fragrance/perfume” on the label) because of allergen potential, so it is best avoided if you have super sensitive skin.

We don't have description for this ingredient yet.

Geraniol - icky
What-it-does: perfuming

Geraniol is a common fragrance ingredient. It smells like rose and can be found in rose oil or in small quantities in geranium, lemon and many other essential oils. 

Just like other similar fragrance ingredients (like linalool and limonene) geraniol also oxidises on air exposure and becomes allergenic. Best to avoid if you have sensitive skin.

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". 

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).

We don't have description for this ingredient yet.

What-it-does: perfuming

A common fragrance ingredient that has a sweet scent somewhere between lily and fruity melon. Can be found in essential oils, such as lavender oil, orange flower oil or ylang-ylang.

In cosmetics, it can be used up to 1%. It’s one of the “EU 26 fragrances” that has to be labelled separately (and cannot be simply included in the term “fragrance/perfume” on the label) because of allergen potential. Best to avoid if your skin is sensitive.

What-it-does: emollient, perfuming

A clear, slightly yellow, odorless oil  that's a very common, medium-spreading emollient. It makes the skin feel nice and smooth and works in a wide range of formulas.

Lecithin - goodie
What-it-does: emollient, emulsifying

A very common ingredient that can be found in all cell membranes. In cosmetics it's quite the multi-tasker: it's an emollient and water-binding ingredient but it's also an emulsifier and can be used for stabilization purposes. It's also often used to create liposomes

A colorless liquid used in small amounts as a so-called masking ingredient, meaning it can hide the natural not-so-nice smell of other cosmetic ingredients. It has a nice rose-like scent and can be found in several essential oils such as rose, neroli or geranium. It also has some antimicrobial activity and can boost the performance of traditional preservatives.

We don't have description for this ingredient yet.

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. 

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.

A synthetic big copolymer molecule that is used as a solubilizer, mild cleansing agent and foam booster or stabilizer. 

If you want to understand poloxamers more, we have a shiny description at Poloxamer 184 and Poloxamer 407. This particular poloxamer, the 188 is quite similar to the 184 version, but it is more water-soluble (80% water-soluble parts) so it can act more as a solubilizer helping to dissolve oil-loving things in water-based formulas. Similar to 184, this one also works as a mild cleansing agent, but while 184 is claimed to be more effective at cleansing, the 188 is better at foaming. 

Ceramide NP - goodie
Also-called: Ceramide 3 | What-it-does: skin-identical ingredient

One of the many types of ceramides that can be found naturally in the upper layer of the skin. Ceramides make up about 50% of the goopy stuff that's between our skin cells and play a super important role in having a healthy skin barrier and keeping the skin hydrated. It works even better when combined with its pal, Ceramide 1.

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

Also-called: Type of Ceramide | What-it-does: skin-identical ingredient

Unlike most other ceramides, this is a tricky one to recognize by name, but Hydroxypalmitoyl Sphinganine is a type of ceramide. The TL;DR version of ceramides is that along with cholesterol and fatty acids, the lipid trio (in a 50%, 25% and 15% ratio) is in the outermost layer of the skin helping to maintain a healthy skin barrier. This means keeping nasty things out, and important things such as water in. We have a more detailed description of ceramides here

So as a ceramide, Hydroxypalmitoyl Sphinganine is a nice skin-identical ingredient that supports a healthy skin barrier. More specifically, a promising in-vitro study on reconstructed human skin shows that applying our molecule helps the skin to make some more ceramides (types 1,2 and 3). Interestingly, the extra ceramide production does not happen in the usual pathway, but the skin seems to process and transform Hydroxypalmitoyl Sphinganine into these other ceramides. 

Clinical, aka made on real people studies, have confirmed that products with Hydroxypalmitoyl Sphinganine improve skin hydration, reduce trans epidermal water loss (the amount of water that evaporates out of the skin), and increase the ceramide content of the skin in people with atopic dermatitis or who are being treated with topical tretinoin. A real goodie in our book. 

What-it-does: soothing

A so-called exopolysaccharide (high-molecular-weight polymers) secreted by a microorganism living in hydrothermal deep vents. The manufacturer claims that it soothes and reduces irritation to sensitive skin against chemical (such as drying acne treatments or strong chemical exfoliants), mechanical (such as micro-cuts after shaving) and UVB aggressors.

Also-called: Butylated Hydroxy Toluene | What-it-does: antioxidant, preservative

It's the acronym for Butylated Hydroxy Toluene. It's a common synthetic antioxidant that's used as a preservative.

There is some controversy around BHT. It's not a new ingredient, it has been used both as a food and cosmetics additive since the 1970s. Plenty of studies tried to examine if it's a carcinogen or not. This Truth in Aging article details the situation and also writes that all these studies examine BHT when taken orally.

As for cosmetics, the CIR (Cosmetic Ingredient Review) concluded that the amount of BHT used in cosmetic products is low (usually around 0.01-0.1%),  it does not penetrate skin far enough to be absorbed into the bloodstream and it is safe to use in cosmetics.

What-it-does: chelating, buffering

A little helper ingredient that is used to adjust the pH of the product. It also helps to keep products stay nice longer by neutralizing the metal ions in the formula (they usually come from water). 

Also-called: Fragrance, Parfum | 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.  

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 emollient | viscosity controlling | emulsifying | surfactant/cleansing
irritancy, com. 1, 2
A super common multitasker ingredient that gives your skin a nice soft feel (emollient) and gives body to creams. [more]
what‑it‑does emollient
A modified dimethicone-type silicone molecule that also contains amino-groups. Having amino-groups means that Amodimethicone also has Nitrogen in its molecule that likes to have a positive charge. [more]
what‑it‑does preservative
what‑it‑does emollient
what‑it‑does solvent | viscosity controlling | perfuming
irritancy, com. 0, 0
what‑it‑does moisturizer/humectant
A glycerin derived, synthetic oily liquid that is also water soluble and works as a great skin moisturizer. [more]
what‑it‑does emulsifying | surfactant/cleansing
what‑it‑does soothing
One of the active parts of Chamomile that is used in skincare as a nice anti-inflammatory and soothing ingredient. [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 preservative
An Ecocert-approved, natural preservative that counts as gentle and non-irritating to the skin. Usually, it comes to the formula as part of a preservative blend as it's not enough on its own.
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 antimicrobial/antibacterial | emulsifying | preservative | surfactant/cleansing
what‑it‑does perfuming
It’s a common fragrance ingredient that has a light floral smell.  It’s one of the “EU 26 fragrances” that has to be labelled separately (and cannot be simply included in the term “fragrance/perfume” [more]
what‑it‑does perfuming
A common fragrance ingredient that smells like jasmine. It is one of the “EU 26 fragrances” that has to be labelled separately because of allergen potential. [more]
what‑it‑does preservative | perfuming | solvent | viscosity controlling
It's one of those things that help your cosmetics not to go wrong too soon, aka a preservative. It can be naturally found in fruits and teas but can also be made synthetically. No matter the origin, in small amounts (up to 1%) it’s a nice, gentle preservative. [more]
what‑it‑does perfuming | solvent
A super common fragrance ingredient found naturally in many plants including citrus peel oils, rosemary or lavender. It autoxidizes on air exposure and counts as a common skin sensitizer. [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 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 perfuming
A common fragrance ingredient with a nice rose-like smell. [more]
what‑it‑does perfuming
With a sweet, light and floral scent, Farnesol is a popular fragrancing ingredient to make your cosmetics that bit nicer to use. It starts its life as a colorless liquid that can either be synthetically created or extracted from loads of plants like citronella, neroli, ylang-ylang, and tuberose.The reason we list it as icky is because Farnesol is one of the “ [more]
what‑it‑does perfuming
A common fragrance ingredient that smells like rose and can be found in rose oil. [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 perfuming
A fragrance with a sweet scent somewhere between lily and fruity melon. [more]
what‑it‑does emollient | perfuming
A clear, slightly yellow, odorless oil  that's a very common, medium-spreading emollient. It makes the skin feel nice and smooth and works in a wide range of formulas.
what‑it‑does emollient | emulsifying
It's quite the multi-tasker: an emollient and water-binding ingredient but also an emulsifier and can be used for stabilization purposes. It's also often used to create liposomes.  [more]
A colorless liquid used in small amounts as a so-called masking ingredient, meaning it can hide the natural not-so-nice smell of other cosmetic ingredients.  [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 emulsifying | surfactant/cleansing
A synthetic big copolymer molecule that is used as a solubilizer, mild cleansing agent and foam booster or stabilizer. If you want to understand poloxamers more, we have a shiny description at Poloxamer 184 and Poloxamer 407. [more]
what‑it‑does skin-identical ingredient
Ceramides make up 50% of the goopy stuff that's between our skin cells and play a super important role in having a healthy skin barrier and keeping the skin hydrated.  [more]
what‑it‑does skin-identical ingredient
Unlike most other ceramides, this is a tricky one to recognize by name, but Hydroxypalmitoyl Sphinganine is a type of ceramide. The TL;DR version of ceramides is that along with cholesterol and fatty acids, the lipid trio (in a 50%, 25% and 15% ratio) is in the outermost layer of the skin helping to maintain a healthy skin barrier. [more]
what‑it‑does soothing
An exopolysaccharide secreted by a microorganism living in hydrothermal deep vents. It protects the skin against chemical, mechanical and UV aggressions. [more]
what‑it‑does antioxidant | preservative
It's the acronym for Butylated Hydroxy Toluene. It's a common synthetic antioxidant that's used as a preservative.There is some controversy around BHT. [more]
what‑it‑does chelating | buffering
A helper ingredient that is used to adjust the pH of the product. Also helps to keep products stay nice longer by neutralizing the metal ions in the formula. 
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]