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Skin science article

K18 Hair Leave-In Molecular Repair Hair Mask Versus The INKEY List PCA Bond Repair Hair Treatment

K18 Hair Leave-In Molecular Repair Hair Mask Versus The INKEY List PCA Bond Repair Hair Treatment What's inside Key Ingredients No key ingredients Benefits Concerns Ingredients Side-by-side Water Alcohol Denat. Propylene Glycol Cetearyl Alcohol Dicaprylyl Ethe

K18 Hair Leave-In Molecular Repair Hair Mask Versus The INKEY List PCA Bond Repair Hair Treatment

What's inside

Key Ingredients

No key ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Alcohol Denat.

Propylene Glycol

Cetearyl Alcohol

Dicaprylyl Ether

Cetyl Esters

Behentrimonium Chloride

Polysorbate 20

Sh-Oligopeptide-78

Hydrolyzed Wheat Protein

Hydrolyzed Wheat Starch

Isopropyl Alcohol

Tocopherol

Phenoxyethanol

Potassium Sorbate

Citric Acid

Parfum

Geraniol

Linalool

Hexyl Cinnamal

Benzyl Alcohol

Water, Alcohol Denat., Propylene Glycol, Cetearyl Alcohol, Dicaprylyl Ether, Cetyl Esters, Behentrimonium Chloride, Polysorbate 20, Sh-Oligopeptide-78, Hydrolyzed Wheat Protein, Hydrolyzed Wheat Starch, Isopropyl Alcohol, Tocopherol, Phenoxyethanol, Potassium Sorbate, Citric Acid, Parfum, Geraniol, Linalool, Hexyl Cinnamal, Benzyl Alcohol

Amodimethicone

Butylene Glycol

Betaine

Bis-PCA Dimethicone

Sorbitan Laurate

Cetrimonium Chloride

Panthenol

Trideceth-12

Glycerin

PEG-40 Hydrogenated Castor Oil

Sodium Benzoate

Hydrolyzed Pea Protein Pg-Propyl Silanetriol

Aminomethyl Propanol

Aloe Barbadensis Leaf Juice Powder

Disodium PEG-12 Dimethicone Sulfosuccinate

Polyglyceryl-4 Laurate

Alcohol

Helianthus Annuus Seed Extract

Dilauryl Citrate

Avena Strigosa Seed Extract

Lecithin

Water, Amodimethicone, Butylene Glycol, Betaine, Bis-PCA Dimethicone, Sorbitan Laurate, Cetrimonium Chloride, Panthenol, Trideceth-12, Glycerin, PEG-40 Hydrogenated Castor Oil, Sodium Benzoate, Hydrolyzed Pea Protein Pg-Propyl Silanetriol, Aminomethyl Propanol, Aloe Barbadensis Leaf Juice Powder, Disodium PEG-12 Dimethicone Sulfosuccinate, Potassium Sorbate, Citric Acid, Polyglyceryl-4 Laurate, Alcohol, Helianthus Annuus Seed Extract, Dilauryl Citrate, Phenoxyethanol, Avena Strigosa Seed Extract, Lecithin

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Alternatives

Ingredients Explained

These ingredients are found in both products.

Ingredients higher up in an ingredient list are typically present in a larger amount.

Citric Acid is an alpha hydroxy acid (AHA) naturally found in citrus fruits like oranges, lemons, and limes.

Like other AHAs, citric acid can exfoliate skin by breaking down the bonds that hold dead skin cells together. This helps reveal smoother and brighter skin underneath.

However, this exfoliating effect only happens at high concentrations (20%) which can be hard to find in cosmetic products.

Due to this, citric acid is usually included in small amounts as a pH adjuster. This helps keep products slightly more acidic and compatible with skin's natural pH.

In skincare formulas, citric acid can:

While it can provide some skin benefits, research shows lactic acid and glycolic acid are generally more effective and less irritating exfoliants.

Most citric acid used in skincare today is made by fermenting sugars (usually from molasses). This synthetic version is identical to the natural citrus form but easier to stabilize and use in formulations.

Rosacea skin has a lower threshold for acids generally, with 62.5% of rosacea subjects in one study reacting to lactic acid in a sting test. This is why we mark citric acid as a potential rosacea trigger.

However, this ingredient shows up as a pH adjuster or chelator at roughly 0.1-1% in many products. These low levels are unlikely to be an issue for rosacea skin and becomes a potential trigger at exfoliating concentrations (20%). Because everybody's skin is unique, we recommend a patch test if you are unsure.

Phenoxyethanol is one of the most widely used preservatives in skincare (and for good reason!).

It has a large spectrum of antimicrobial activity and especially effective bacteria, yeast, and mold while only having a weak effect on your skin's natural microbiome.

On a cellular level, it disrupts the cell membranes of microbes by poking holes that make the cell leak. This shuts down the chemical reactions the microbe needs to make energy so it can no longer survive.

Another perk of this ingredient is that it stays functional across a wide pH range (3-10).

You'll often see it paired with boosters like Ethylhexylglycerin; one study showed that a 1:9 ratio of Ethylhexylglycerin to Phenoxyethanol damages bacterial membranes as effectively as doubling the Phenoxyethanol concentration on its own.

Typical use concentrations range from 0.3-1% depending on the formula, and this ingredient is capped at 1% int the EU.

Safety-wise, the fear mongering does not hold up to the evidence. The EU's Scientific Committee on Consumer Safety and FDA consider it safe as a preservative at up to 1%, including for children of all ages.

Adverse systemic effects only showed up in animal studies at exposures roughly 200x higher than what people get from cosmetics. And despite its very widespread use, this ingredient is a rare sensitizer and allergic reactions are uncommon.

Potassium Sorbate is a preservative used to prevent yeast and mold in products. It is commonly found in both cosmetic and food products.

This ingredient comes from potassium salt derived from sorbic acid. Sorbic acid is a natural antibiotic and effective against fungus.

Both potassium sorbate and sorbic acid can be found in baked goods, cheeses, dried meats, dried fruit, ice cream, pickles, wine, yogurt, and more.

You'll often find this ingredient used with other preservatives.

Water. It's the most common cosmetic ingredient of all. You'll usually see it at the top of ingredient lists, meaning that it makes up the largest part of the product.

So why is it so popular? Water most often acts as a solvent - this means that it helps dissolve other ingredients into the formulation.

You'll also recognize water as that liquid we all need to stay alive. If you see this, drink a glass of water. Remember to stay hydrated!

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The reference edit

Ingredients, questions
& further reading.

Connected source records selected through this article’s public topic index.

01

Formula cabinet

Ingredients & structured notes

Ingredient index

Ingredients Side-by-side

  1. 01Water
  2. 02Propanediol
  3. 03Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer
  4. 04Squalane
  5. 05Phenoxyethanol
  6. 06Fructose
  7. 07Glycerin
  8. 08Sorbitan Isostearate
  9. 09Polysorbate 60
  10. 10Withania Somnifera Root Extract
  11. 11Ethylhexylglycerin
  12. 12Disodium EDTA
  13. 13Tocopherol
  14. 14Eucalyptus Globulus Leaf Oil
  15. 15Helianthus Annuus Seed Oil
  16. 16Biosaccharide Gum-4
  17. 17Potassium Sorbate
  18. 18Citric Acid
  19. 19Limonene
  20. 20Water, Propanediol, Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Squalane, Phenoxyethanol, Fructose, Glycerin, Sorbitan Isostearate, Polysorbate 60, Withania Somnifera Root Extract, Ethylhexylglycerin, Disodium EDTA, Tocopherol, …
Source · skinsort.com
02

Product index

Related product references

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The Inkey List Brighten-i Eye Cream The Inkey List Brighten-i Eye Cream ingredients explained: Water (Aqua/Eau), Dimethicone, Coco-Caprylate/Caprate, Glycerin, Caprylic/Capric Triglyceride,…

Source: incidecoder.comView reference →
03

Comparison edit

Read side by side