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Kiehl's Auto-Tone Discoloration & UV Solution SPF 30 Versus Beauty of Joseon Relief Sun : Rice + Probiotics SPF 50+ PA++++

Kiehl's Auto-Tone Discoloration & UV Solution SPF 30 Versus Beauty of Joseon Relief Sun : Rice + Probiotics SPF 50+ PA++++ This brightening treatment is formulated around Niacinamide and 2-Mercaptonicotinoyl Glycine to fade the look of dark spots and brighten

Kiehl's Auto-Tone Discoloration & UV Solution SPF 30 Versus Beauty of Joseon Relief Sun : Rice + Probiotics SPF 50+ PA++++

This brightening treatment is formulated around Niacinamide and 2-Mercaptonicotinoyl Glycine to fade the look of dark spots and brighten dull-looking skin.

This chemical sunscreen covers the full UV range and blocks ~98% of UVB at SPF 50.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Butyl Methoxydibenzoylmethane 3%

Homosalate 10%

Ethylhexyl Salicylate 5%

Octocrylene 7%

Water

C15-19 Alkane

Niacinamide

Glycerin

Butylene Glycol

Silica

Titanium Dioxide

Hydroxyacetophenone

Pentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate

Potassium Hydroxide

Sodium Thiosulfate

Taraxacum Officinale Rhizome/Root Extract

Trisodium Ethylenediamine Disuccinate

2-Mercaptonicotinoyl Glycine

Butyrospermum Parkii Butter

Ammonium Acryloyldimethyltaurate/Vp Copolymer

Arachidyl Alcohol

Arachidyl Glucoside

Behenyl Alcohol

Caprylyl Glycol

Carbomer

Citric Acid

Mica

Pentylene Glycol

Poly C10-30 Alkyl Acrylate

Polyglyceryl-4 Caprate

Sodium Dilauramidoglutamide Lysine

Tin Oxide

Xanthan Gum

CI 14700

Phenoxyethanol

Butyl Methoxydibenzoylmethane 3%, Homosalate 10%, Ethylhexyl Salicylate 5%, Octocrylene 7%, Water, C15-19 Alkane, Niacinamide, Glycerin, Butylene Glycol, Silica, Titanium Dioxide, Hydroxyacetophenone, Pentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate, Potassium Hydroxide, Sodium Thiosulfate, Taraxacum Officinale Rhizome/Root Extract, Trisodium Ethylenediamine Disuccinate, 2-Mercaptonicotinoyl Glycine, Butyrospermum Parkii Butter, Ammonium Acryloyldimethyltaurate/Vp Copolymer, Arachidyl Alcohol, Arachidyl Glucoside, Behenyl Alcohol, Caprylyl Glycol, Carbomer, Citric Acid, Mica, Pentylene Glycol, Poly C10-30 Alkyl Acrylate, Polyglyceryl-4 Caprate, Sodium Dilauramidoglutamide Lysine, Tin Oxide, Xanthan Gum, CI 14700, Phenoxyethanol

Dibutyl Adipate

Propanediol

Diethylamino Hydroxybenzoyl Hexyl Benzoate

Polymethylsilsesquioxane

Ethylhexyl Triazone

Methylene Bis-Benzotriazolyl Tetramethylbutylphenol

Coco-Caprylate/Caprate

Caprylyl Methicone

Diethylhexyl Butamido Triazone

1,2-Hexanediol

Oryza Sativa Extract

Oryza Sativa Germ Extract

Camellia Sinensis Leaf Extract

Lactobacillus/Pumpkin Ferment Extract

Bacillus/Soybean Ferment Extract

Saccharum Officinarum Extract

Macrocystis Pyrifera Extract

Cocos Nucifera Fruit Extract

Panax Ginseng Root Extract

Monascus/Rice Ferment

Polyglyceryl-3 Methylglucose Distearate

Decyl Glucoside

Tromethamine

Acrylates/C10-30 Alkyl Acrylate Crosspolymer

Sodium Stearoyl Glutamate

Polyacrylate Crosspolymer-6

Adenosine

T-Butyl Alcohol

Tocopherol

Lactobacillus/Rice Ferment

Aspergillus Ferment

Saccharomyces/Rice Ferment Filtrate

Ethylhexylglycerin

Water, Dibutyl Adipate, Propanediol, Diethylamino Hydroxybenzoyl Hexyl Benzoate, Polymethylsilsesquioxane, Ethylhexyl Triazone, Niacinamide, Methylene Bis-Benzotriazolyl Tetramethylbutylphenol, Coco-Caprylate/Caprate, Caprylyl Methicone, Diethylhexyl Butamido Triazone, Glycerin, 1,2-Hexanediol, Butylene Glycol, Oryza Sativa Extract, Oryza Sativa Germ Extract, Camellia Sinensis Leaf Extract, Lactobacillus/Pumpkin Ferment Extract, Bacillus/Soybean Ferment Extract, Saccharum Officinarum Extract, Macrocystis Pyrifera Extract, Cocos Nucifera Fruit Extract, Panax Ginseng Root Extract, Monascus/Rice Ferment, Behenyl Alcohol, Poly C10-30 Alkyl Acrylate, Polyglyceryl-3 Methylglucose Distearate, Decyl Glucoside, Tromethamine, Carbomer, Acrylates/C10-30 Alkyl Acrylate Crosspolymer, Sodium Stearoyl Glutamate, Polyacrylate Crosspolymer-6, Adenosine, Xanthan Gum, T-Butyl Alcohol, Tocopherol, Lactobacillus/Rice Ferment, Aspergillus Ferment, Saccharomyces/Rice Ferment Filtrate, Pentylene Glycol, Ethylhexylglycerin

Reviews

Alternatives

Ingredients Explained

These ingredients are found in both products.

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

Behenyl Alcohol is a type of fatty alcohol (these are different from the drying, solvent alcohols).

Fatty Alcohols have hydrating properties and are most often used as an emollient or to thicken a product. They are usually derived from natural fats and oils; behenyl alcohol is derived from the fats of vegetable oils.

Emollients help keep your skin soft and hydrated by creating a film that traps moisture in.

In 2000, Behenyl Alcohol was approved by the US as medicine to reduce the duration of cold sores.

Butylene Glycol (or BG) is used within cosmetic products for a few different reasons:

Overall, Butylene Glycol is a safe and well-rounded ingredient that works well with other ingredients.

Though this ingredient works well with most skin types, some people with sensitive skin may experience a reaction such as allergic rashes, closed comedones, or itchiness.

Carbomer is a synthetic thickening and gelling agent. It's basically the ingredient that gives a lot of serums, gels, creams, and sunscreens their smooth, non-sticky texture.

Although legally permitted at very high levels, carbomers are normally used at concentrations below 1%.

It also needs to be neutralized to actually thicken, and because it is a large molecule, it doesn't really penetrate the skin barrier.

Allergy-wise, the risk is very low. Clinical studies show carbomers have low potential for skin irritation/sensitization even at concentrations up to 100%.

A 2024 UK study patch-tested 1,302 patients and found true allergy to the parent group of carbomer to be rare with no confirmed relevant reactions.

Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.

Topically, glycerin does several things at once:

Your skin makes glycerin on its own (mostly from sebaceous oil breakdown) and shuttles it to your outermost layer of skin, or your epidermis, via aquaporin-3.

Aquaporin-3 is a transporter that is essential for normal skin hydration, elasticity, and repair. Interestingly, mice lacking in AQP3 have dry and less elastic skin that can be fully corrected with glycerin.

This ingredient is non-irritating, plays well with almost every ingredient, and works across all skin types. Typical use is anywhere between 3-10% but can go up to 79% in some leave-on products.

Just know very high concentrations (>40%) can feel tacky in low humidity.

Glycerin is the name for this ingredient in American English. British English uses Glycerol/Glycerine.

Niacinamide is a multitasking form of vitamin B3 that strengthens the skin barrier, reduces pores and dark spots, regulates oil, and improves signs of aging.

And the best part? It's gentle and well-tolerated by most skin types, including sensitive and reactive skin.

You might have heard of "niacin flush", or the reddening of skin that causes itchiness. Niacinamide has not been found to cause this.

In very rare cases, some individuals may not be able to tolerate niacinamide at all or experience an allergic reaction to it.

If you are experiencing flaking, irritation, and dryness with this ingredient, be sure to double check all your products as this ingredient can be found in all categories of skincare.

When incorporating niacinamide into your routine, look out for concentration amounts. Typically, 5% niacinamide provides benefits such as fading dark spots. However, if you have sensitive skin, it is better to begin with a smaller concentration.

When you apply niacinamide to your skin, your body converts it into nicotinamide adenine dinucleotide (NAD). NAD is an essential coenzyme that is already found in your cells as "fuel" and powers countless biological processes.

In your skin, NAD helps repair cell damage, produce new healthy cells, support collagen production, strengthen the skin barrier, and fight environmental stressors (like UV and pollution).

Our natural NAD levels start to decline with age, leading to slower skin repair, visible aging, and a weaker skin barrier. By providing your skin niacinamide, you're recharging your skin's NAD levels. This leads to stronger, healthier, and younger looking skin.

Another name for vitamin B3 is nicotinamide. This vitamin is water-soluble and our bodies don't store it. We obtain Vitamin B3 from either food or skincare. Meat, fish, wheat, yeast, and leafy greens contain vitamin B3.

The type of niacinamide used in skincare is synthetically created.

Pentylene Glycol (1,2-pentanediol) is a multitasking little diol with three main roles in a formula:

Research on alkanediols (the family pentylene glycol belongs to) show they work by disrupting microbial cell membranes. This disruption helps the primary preservative system in a product work more effectively at lower doses.

On the safety side, the Cosmetic Ingredient Review Expert Panel has concluded this ingredient to be safe as used in current cosmetic practices + concentrations.

Typical use levels in a formula run about 1-5%.

Poly C10-30 Alkyl Acrylate is a synthetic polymer. It's a long chain built from acrylic acid units and each unit carries a fatty "tail" derived form a C10-30 alcohol.

Those oil-loving tails allow this ingredient to thicken oil phases, hold emulsions together, and cuts the tacky/greasy feel of heavy formulas.

Typical use levels sit around 0.1-3%, with 0.3-3% more common in leave-on emulsions.

This ingredient was reviewed as part of a group of 126 acrylates and concluded to be safe by the Cosmetic Ingredient Review Expert Panel.

Though acrylate contact allergy is real and well-documented, allergy risk is quite low. The cases of documented contact allergy are caused by unreacted monomers (more commonly found in gel nails, dental resins, and adhesives).

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!

Xanthan gum is used as a stabilizer and thickener within cosmetic products. It helps give products a sticky, thick feeling - preventing them from being too runny.

On the technical side of things, xanthan gum is a polysaccharide - a combination consisting of multiple sugar molecules bonded together.

Xanthan gum is a pretty common and great ingredient. It is a natural, non-toxic, non-irritating ingredient that is also commonly used in food products.

Similar Comparisons

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. 03Glycerin
  4. 04Dipropylene Glycol
  5. 05Butylene Glycol
  6. 06Caprylyl Glycol
  7. 07Hydroxyacetophenone
  8. 08Pentylene Glycol
  9. 09Betaine
  10. 10Panthenol
  11. 11C12-14 Pareth-12
  12. 12Sodium Citrate
  13. 13Disodium EDTA
  14. 14Citric Acid
  15. 151,2-Hexanediol
  16. 16Sodium Hyaluronate
  17. 17Hydrolyzed Hyaluronic Acid
  18. 18Hydroxypropyltrimonium Hyaluronate
  19. 19Sodium Hyaluronate Crosspolymer
  20. 20Sodium Acetylated Hyaluronate
Source · skinsort.com
02

Product index

Related product references

03

Comparison edit

Read side by side