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Kiehl’s Auto-tone Discoloration & UV Serum

Auto-tone Discoloration & UV Serum

Our discoloration treatment with spf and 0.5% melasyl works to harmonize the look of skin’s natural tone by visibly reducing dark spots, dark patches, and post-blemish marks. Featuring patent-pending technology, our all over formula with broad spectrum spf 30 helps to protect against uv damage, while leaving skin with a radiant, healthy-looking appearance.
Uploaded by: pinkunicornskincare on

Skim through

Ingredient name what-it-does irr., com. ID-Rating
Avobenzone (3%) sunscreen goodie
Homosalate (10%) sunscreen
Octisalate (5%) sunscreen 0, 0
Octocrylene (7%) sunscreen
Water solvent
C15-19 Alkane emollient
Niacinamide cell-communicating ingredient, skin brightening, anti-acne, moisturizer/​humectant superstar
Glycerin skin-identical ingredient, moisturizer/​humectant 0, 0 superstar
Butylene Glycol moisturizer/​humectant, solvent 0, 1
Silica viscosity controlling
Titanium Dioxide sunscreen, colorant goodie
Hydroxyacetophenone antioxidant
Pentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate antioxidant, preservative
Potassium Hydroxide buffering
Sodium Thiosulfate
Taraxacum Officinale (Dandelion) Rhizome Root Extract soothing
Trisodium Ethylenediamine Disuccinate chelating
2-Mercaptonicotinoyl Glycine
Butyrospermum Parkii (Shea) Butter emollient goodie
Ammonium Acryloyldimethyltaurate/VP Copolymer viscosity controlling
Arachidyl Alcohol emollient, viscosity controlling
Arachidyl Glucoside emulsifying, surfactant/​cleansing
Behenyl Alcohol emollient, viscosity controlling
Caprylyl Glycol moisturizer/​humectant, emollient
Carbomer viscosity controlling 0, 1
Citric Acid buffering
Mica colorant
Pentylene Glycol solvent, moisturizer/​humectant
Poly C10-30 Alkyl Acrylate viscosity controlling
Polyglyceryl-4 Caprate emulsifying
Sodium Dilauramidoglutamide Lysine moisturizer/​humectant, emulsifying
Tin Oxide colorant, abrasive/​scrub, viscosity controlling
Xanthan Gum viscosity controlling
Red 4 colorant
Phenoxyethanol preservative

Kiehl’s Auto-tone Discoloration & UV Serum
Ingredients explained

Also-called: Butyl Methoxydibenzoylmethane | What-it-does: sunscreen

The famous Avobenzone. It is a special snowflake as it is the only globally available chemical sunscreen agent that provides proper UVA protection (in the US, new generation sunscreen agents are not approved because of impossible FDA regulations). It is the global gold standard of UVA protection and is the most used UVA sunscreen in the world. 

It gives very good protection across the whole UVA range (310-400 nm that is both UVA1 and UVA2) with a peak protection at 360 nm. The problem with it, though, is that it is not photostable and degrades in the sunlight. Wikipedia says that avobenzone loses 36% of its UV-absorption capacity after just one hour of sunlight (yep, this is one of the reasons why sunscreens have to be reapplied after a few hours).

What-it-does: sunscreen

An oil-soluble chemical sunscreen agent that protects the skin from UVB (295-315 nm) with a peak protection at 306 nm. Homosalate is not a strong UV filter in and of itself (gives only SPF 4.3 protection at max. allowed 10% concentration) and it is not photostable (looses 10% of its SPF protection in 45 mins) so it always has to be combined with other sunscreens for proper protection. Its big advantage, though, is that it is a liquid and is excellent for dissolving other hard to solubilize powder sunscreen agents, like the famous Avobenzone.

Regarding Homosalate's safety profile, we do not have the best news. In-vitro (made in the labs) studies have shown that it might have some estrogenic activity. Do not panic, these studies were not conducted on real humans under real world conditions. Still, if you are a 'better safe than sorry' type, be careful when using Homosalate containing sunscreens long-term and full-body.

Also-called: Octyl Salicylate, Octisalate;Ethylhexyl Salicylate | What-it-does: sunscreen | Irritancy: 0 | Comedogenicity: 0

A colorless to light yellowish oily liquid that works as a UVB (280-320nm) sunscreen filter with a peak absorbance at 306 nm. It's not a strong filter in itself, it's always used in combination with other sunscreen agents to further enhance the SPF and to solubilize other solid UV filters.

It has a good safety profile and is allowed to be used at a max concentration of 5% both in the US and in Europe (10% is allowed in Japan).

What-it-does: sunscreen

An oil-soluble chemical sunscreen agent that protects skin in the UVB and somewhat in the UVA II range with a peak absorption of 304 nm. Its protection is not strong enough on its own but it is quite photostable (loses 10% of SPF protection in 95 mins) and is often used to stabilize other photo-unstable UV-filters, for example, Avobenzone. It is also often used to improve the water resistance of the products. 

Octocrylene's safety profile is generally quite good, though a review study in Contact Dermatitis reports an "increasing number of patients with photo contact allergy to octocrylene." Mainly adults with ketoprofen-sensitivity and children with sensitive skin are affected, so if you have a small kid, it is probably better to use octocrylene-free sunscreens.

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: emollient

A nice-feeling, light emollient that makes the skin soft and smooth. It gives a fresh and gliding sensation with a powdery or soft after-feel depending on the exact grade used. It is a popular alternative to replace silicones. 

Chemically speaking, it is an alkane (stable, non-reacting hydrocarbon) that used to be produced from petrochemicals, but today's versions are typically vegetable based. It is readily biodegradable. 

Niacinamide - superstar
Also-called: vitamin B3, nicotinamide | What-it-does: cell-communicating ingredient, skin brightening, anti-acne, moisturizer/humectant
  • A multi-functional skincare superstar with several proven benefits for the skin
  • Great anti-aging, wrinkle smoothing ingredient used at 4-5% concentration
  • Fades brown spots alone or in combination with amino sugar, acetyl glucosamine
  • Increases ceramide synthesis that results in a stronger, healthier skin barrier and better skin hydration
  • Can help to improve several skin conditions including acne, rosacea, and atopic dermatitis
Read all the geeky details about Niacinamide here >>

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 for dry skin at higher concentrations up to 20-40%
  • High-glycerin moisturizers are awesome for treating severely dry skin
Read all the geeky details about Glycerin here >>

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.

A white powdery thing that's the major component of glass and sand. In cosmetics, it’s often in products that are supposed to keep your skin matte as it has great oil-absorbing abilities. It’s also used as a helper ingredient to thicken up products or suspend insoluble particles. 

What-it-does: sunscreen, colorant

Titanium Dioxide is one of the two members of the elite sunscreen group called physical sunscreens (or inorganic sunscreens if you’re a science geek and want to be precise).

Traditionally, UV-filters are categorized as either chemical or physical. The big difference is supposed to be that chemical agents absorb UV-light while physical agents reflect it like a bunch of mini umbrellas on top of the skin. While this categorization is easy and logical it turns out it's not true. A recent, 2016 study shows that inorganic sunscreens work mostly by absorption, just like chemical filters, and only a little bit by reflection (they do reflect the light in the visible spectrum, but mostly absorb in the UV spectrum).

What-it-does: antioxidant

A handy multifunctional ingredient that works as a preservative booster, as well as an antioxidant and soothing agent

Also-called: Tinogard TT | What-it-does: antioxidant, preservative

Pentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate is an antioxidant molecule used in small amounts (less than 0.8%) to help products stay nice longer. More specifically, it is great at preventing discoloration or other types of oxidative degradation. It is a trendy alternative to often bad-mouthed synthetic antioxidant and stabilizer, BHT

What-it-does: buffering

It's a very alkaline stuff that helps to set the pH of the cosmetic formula to be just right. It's similar to the more often used sodium hydroxide and pretty much the same of what we wrote there applies here too. 

We don't have description for this ingredient yet.

What-it-does: soothing

We don't have description for this ingredient yet.

Also-called: EDDS | What-it-does: chelating

A helper ingredient that helps to neutralize the metal ions in the formula (they usually come from water) so it stays nice longer. The special property of this particular ingredient is that it's more effective against more problematic ions, like Cu (copper) and Fe (iron) compared to less problematic ones like Ca (calcium)  and Mg (magnesium).

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

Also-called: Shea Butter | What-it-does: emollient

Unless you live under a rock you must have heard about shea butter. It's probably the most hyped up natural butter in skincare today. It comes from the seeds of African Shea or Karite Trees and used as a magic moisturizer and emollient.

But it's not only a simple emollient, it regenerates and soothes the skin, protects it from external factors (such as UV rays or wind) and is also rich in antioxidants (among others vitamin A, E, F, quercetin and epigallocatechin gallate). If you are looking for rich emollient benefits + more, shea is hard to beat. 

Also-called: Aristoflex AVC | What-it-does: viscosity controlling

A kind of polymer (big molecule from repeated subunits) that helps to create beautiful gel-like textures. It's also a texturizer and thickener for oil-in-water emulsions. It gives products a good skin feel and does not make the formula tacky or sticky. 

It works over a wide pH range and is used between 0.5-1.2%.

A fatty alcohol (the non-drying type with a long oil loving chain of 20 carbon atoms) that is used to increase the viscosity of the formula and it also helps the oily and the watery parts to stay nicely mixed together (called emulsion stabilizing). 

An ingredient that is created from the attachment of the water-loving sugar molecule, glucose, and an oil-loving 20 carbon long fatty chain. This makes it a partly water- and partly oil-soluble material, meaning it functions as an emulsifier helping oil and water to mix.  

Most often, it comes to the formula coupled with two fatty alcohol friends, Arachidyl and Behenyl alcohol, to make up an emulsifier trio trade named Montanov 202. As described by its manufacturer, the main thing of Montanonv 202 is that it gives creams a unique evanescent and light feel with a matt finish. It also leaves the skin soft, but not oily, is hypoallergenic and non-comedogenic making it perfect for both oily and sensitive skin formulas. 

A fatty alcohol (the non-drying type with a long oil loving chain of 22 carbon atoms) that is used to increase the viscosity of the formula and it also helps the oily and the watery parts to stay nicely mixed together (called emulsion stabilizing). 

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: 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.

What-it-does: buffering

Citric acid comes from citrus fruits and is an AHA. If these magic three letters don’t tell you anything, click here and read our detailed description on glycolic acid, the most famous AHA. 

So citric acid is an exfoliant, that can - just like other AHAs - gently lift off the dead skin cells of your skin and make it more smooth and fresh. 

Also-called: CI 77019 | What-it-does: colorant

A super versatile and common mineral powder that comes in different particle sizes. It is a multi-tasker used to improve skin feel, increase product slip, give the product light-reflecting properties, enhance skin adhesion or serve as an anti-caking agent.

It is also the most commonly used "base" material for layered composite pigments such as pearl-effect pigments. In this case, mica is coated with one or more metal oxides (most commonly titanium dioxide) to achieve pearl effect via the physical phenomenon known as interference. 

A multi-functional, silky feeling helper ingredient that can do quite many things. It's used as an emulsion stabilizer, solvent and a broad spectrum antimicrobial. According to manufacturer info, it's also a moisturizer and helps to make the product feel great on the skin. It works synergistically with preservatives and helps to improve water-resistance of sunscreens. 

We don't have description for this ingredient yet.

What-it-does: emulsifying

A water-loving emollient that is used as a solubilizer in water-based, toner-like formulas. Solubilizers are handy helper ingredients to dissolve small amounts of oil-loving materials (such as essential oils or fragrances) into watery liquids. Polyglyceryl-4 Caprate also has some emollient properties, making the skin feel nice and smooth. 

We don't have description for this ingredient yet.

Also-called: CI 77861, Tin Dioxide | What-it-does: colorant, abrasive/scrub, viscosity controlling

Far from the tin cans you find in the supermarket, Tin Oxide is mostly used when dealing with so-called effect pigments, tricky composite pigments that can do color travel (change color depending on the viewing angle) or give multiple color effect. 

It's often found alongside Mica (as a base material) and Titanium Dioxide (as a coating) to give a glossy, pearlescent effect. Together, they make up a trademarked technology called RonaFlair Blanace from the German manufacturer Merck. According to their info, this combination can balance out undesirable tones in the skin, making it a popular choice for brightening products and highlighters.

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). 

Also-called: Ci 14700 | What-it-does: colorant

A common colorant that gives products a nice red color.

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 sunscreen
Avobenzone - the only globally available chemical sunscreen that gives proper UVA protection. It is not photostable so has to be combined with ingredients that help to stabilize it. [more]
what‑it‑does sunscreen
An oil-soluble chemical sunscreen agent that protects the skin from UVB (295-315 nm) with a peak protection at 306 nm. Homosalate is not a strong UV filter in and of itself (gives only SPF 4.3 protection at max. [more]
what‑it‑does sunscreen
irritancy, com. 0, 0
A colorless to light yellowish oily liquid that works as a UVB (280-320nm) sunscreen filter with a peak absorbance at 306 nm. It's not a strong filter in itself, it's always used in combination with other sunscreen agents. [more]
what‑it‑does sunscreen
An oil-soluble chemical sunscreen agent that protects skin in the UVB and somewhat in the UVA II range with a peak absorption of 304 nm. [more]
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
A nice-feeling, light emollient that makes the skin soft and smooth. It gives a fresh and gliding sensation with a powdery or soft after-feel depending on the exact grade used. [more]
what‑it‑does cell-communicating ingredient | skin brightening | anti-acne | moisturizer/humectant
A multi-functional skincare superstar that has clinically proven anti-aging, skin lightening, anti-inflammatory and barrier repair properties. [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 | 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 viscosity controlling
A white powdery thing that can mattify the skin and thicken up cosmetic products. [more]
what‑it‑does sunscreen | colorant
A physical/inorganic sunscreen with pretty broad spectrum (UVB and UVA II, less good at UVA I) protection and good stability. Might leave some whitish tint on the skin, though. [more]
what‑it‑does antioxidant
A handy multifunctional ingredient that works as a preservative booster, as well as an antioxidant and soothing agent.
what‑it‑does antioxidant | preservative
Pentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate is an antioxidant molecule used in small amounts (less than 0.8%) to help products stay nice longer. More specifically, it is great at preventing discoloration or other types of oxidative degradation. [more]
what‑it‑does buffering
It's a very alkaline stuff that helps to set the pH of the cosmetic formula to be just right. [more]
what‑it‑does soothing
what‑it‑does chelating
A helper ingredient that helps to neutralize the metal ions in the formula (they usually come from water) so it stays nice longer. [more]
what‑it‑does emollient
Shea butter that's considered to be a magic moisturizer and emollient. It is also soothing and rich in antioxidants. [more]
what‑it‑does viscosity controlling
A kind of polymer (big molecule from repeated subunits) that helps to create beautiful gel-like textures. It's also a texturizer and thickener for oil-in-water emulsions. [more]
what‑it‑does emollient | viscosity controlling
A fatty alcohol (the non-drying type with a long oil loving chain of 20 carbon atoms) that is used to increase the viscosity of the formula and it also helps the oily and the watery parts to stay nicely mixed together (called emulsion stabilizing).  [more]
what‑it‑does emulsifying | surfactant/cleansing
An ingredient that is created from the attachment of the water-loving sugar molecule, glucose, and an oil-loving 20 carbon long fatty chain. This makes it a partly water- and partly oil-soluble material, meaning it functions as an emulsifier helping oil and water to mix.   Most often, it comes to the formula coupled with two fatty alcohol friends, Arachidyl and Behenyl alcohol, to make [more]
what‑it‑does emollient | viscosity controlling
A fatty alcohol (the non-drying type) that is used to increase the viscosity of the formula and stabilize emulsions. [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 viscosity controlling
irritancy, com. 0, 1
A handy white powder that magically converts a liquid into a nice gel formula. [more]
what‑it‑does buffering
An AHA that comes from citrus fruits. It is usually used as a helper ingredient to adjust the pH of the formula. [more]
what‑it‑does colorant
A mineral powder used to improve skin feel, increase product slip, give the product some light-reflecting properties, enhance skin adhesion or serve as an anti-caking agent. A real multi-tasker. [more]
what‑it‑does solvent | moisturizer/humectant
A multi-functional, silky feeling helper ingredient that can do quite many things. It's used as an emulsion stabilizer, solvent, and a broad spectrum antimicrobial. [more]
what‑it‑does viscosity controlling
what‑it‑does emulsifying
A water-loving emollient that is used as a solubilizer in water-based, toner-like formulas. Solubilizers are handy helper ingredients to dissolve small amounts of oil-loving materials (such as essential oils or fragrances) into watery liquids. [more]
what‑it‑does moisturizer/humectant | emulsifying
what‑it‑does colorant | abrasive/scrub | viscosity controlling
Far from the tin cans you find in the supermarket, Tin Oxide is mostly used when dealing with so-called effect pigments, tricky composite pigments that can do color travel (change color depending on the viewing angle) or give multiple color effect.  It's often found alongside Mica (as a base material) and Titanium Dioxide (as a coating) to give a glossy, pearlescent effect. [more]
what‑it‑does viscosity controlling
A super commonly used thickener and emulsion stabilizer. [more]
what‑it‑does colorant
A common colorant that gives products a nice red color.
what‑it‑does preservative
Pretty much the current IT-preservative. It’s safe and gentle, and can be used up to 1% worldwide. [more]