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Peter Thomas Roth Retinol Fusion Pm Eye Cream

Retinol Fusion Pm Eye Cream

Eye cream for night use.
Uploaded by: mrsfraser07 on

Highlights

#fragrance & essentialoil-free
Fragrance and Essential Oil Free

Skim through

Ingredient name what-it-does irr., com. ID-Rating
Water solvent
Glyceryl Stearate emollient, emulsifying 0, 1-2
Caprylic/Capric Triglyceride emollient
Cetyl Alcohol emollient, viscosity controlling 2, 2
Propylene Glycol Stearate surfactant/​cleansing 0-1, 0-3
Cera Alba (Beeswax) emollient, viscosity controlling, emulsifying, perfuming 0, 0-2
Caffeine antioxidant, perfuming goodie
Retinol cell-communicating ingredient superstar
Butyrospermum Parkii (Shea) Butter emollient, viscosity controlling goodie
Persea Gratissima (Avocado) Oil antioxidant, emollient 0, 0-3 goodie
Ascorbic Acid antioxidant, skin brightening, buffering superstar
Retinyl Palmitate cell-communicating ingredient 1-3, 1-3
Tocopheryl Acetate antioxidant 0, 0
Sodium Hyaluronate skin-identical ingredient, moisturizer/​humectant 0, 0 goodie
Sodium PCA skin-identical ingredient, moisturizer/​humectant 0, 0 goodie
BHT antioxidant, preservative
Superoxide Dismutase antioxidant goodie
Squalane skin-identical ingredient, emollient 0, 1 goodie
Aloe Barbadensis Leaf Juice soothing, moisturizer/​humectant goodie
Soluble Collagen moisturizer/​humectant goodie
Hydrolyzed Elastin moisturizer/​humectant, emollient
Lecithin emollient, emulsifying goodie
Allantoin soothing 0, 0 goodie
Panthenol soothing, moisturizer/​humectant 0, 0 goodie
Ceramide NP skin-identical ingredient goodie
Echinacea Purpurea Extract moisturizer/​humectant
Algae Extract emollient, moisturizer/​humectant goodie
C13-14 Isoparaffin emollient, viscosity controlling, solvent
Foeniculum Vulgare (Fennel) Seed Extract
Rosa Canina Fruit Oil emollient
Viola Tricolor Extract emollient, soothing
Camellia Sinensis Leaf Extract antioxidant, soothing superstar
Dimethicone emollient 0, 1
Helianthus Annuus (Sunflower) Seed Oil emollient 0, 0 goodie
Wheat Amino Acids soothing
Potassium Phosphate buffering
Leuconostoc/Radish Root Ferment Filtrate antimicrobial/​antibacterial, preservative
Citric Acid buffering
Disodium EDTA chelating
Carbomer viscosity controlling 0, 1
Triethanolamine buffering 0, 2
Steapyrium Chloride antimicrobial/​antibacterial
Polyacrylamide viscosity controlling
Polysorbate 20 emulsifying, surfactant/​cleansing 0, 0
Oleic Acid emollient, emulsifying
Soy Acid emollient, emulsifying
Laureth-7 emulsifying, surfactant/​cleansing
Ascorbyl Methylsilanol Pectinate antioxidant, viscosity controlling
EDTA chelating
Methylpropanediol solvent
Butylene Glycol moisturizer/​humectant, solvent, viscosity controlling 0, 1
Propylene Glycol moisturizer/​humectant, solvent, viscosity controlling 0, 0
Potassium Sorbate preservative
Sodium Benzoate preservative
Pentylene Glycol solvent, moisturizer/​humectant
Alcohol antimicrobial/​antibacterial, solvent, viscosity controlling icky
Phenoxyethanol preservative

Peter Thomas Roth Retinol Fusion Pm Eye Cream
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: emollient, emulsifying | Irritancy: 0 | Comedogenicity: 1-2

A super common, waxy, white, solid stuff that helps water and oil to mix together, gives body to creams and leaves the skin feeling soft and smooth.

Chemically speaking, it is the attachment of a glycerin molecule to the fatty acid called stearic acid. It can be produced from most vegetable oils (in oils three fatty acid molecules are attached to glycerin instead of just one like here) in a pretty simple, "green" process that is similar to soap making. It's readily biodegradable.

What-it-does: emollient

A super common emollient that makes your skin feel nice and smooth. It comes from coconut oil and glycerin, it’s light-textured, clear, odorless and non-greasy. It’s a nice ingredient that just feels good on the skin, is super well tolerated by every skin type and easy to formulate with. No wonder it’s popular. 

What-it-does: emollient, viscosity controlling, emulsion stabilising | Irritancy: 2 | Comedogenicity: 2

A so-called fatty (the good, non-drying kind of) alcohol that does all kinds of things in a skincare product: it makes your skin feel smooth and nice (emollient), helps to thicken up products and also helps water and oil to blend (emulsifier). Can be derived from coconut or palm kernel oil.

What-it-does: surfactant/cleansing | Irritancy: 0-1 | Comedogenicity: 0-3

We don't have description for this ingredient yet.

Also-called: Beeswax | What-it-does: emollient, viscosity controlling, emulsifying, perfuming | Irritancy: 0 | Comedogenicity: 0-2

It's the yellow, solid stuff that you probably know from beeswax candles. It's a natural material produced by honey bees to build their honeycomb.

As for skincare, it's used as an emollient and thickening agent. It's super common in lip balms and lipsticks. 

Caffeine - goodie
What-it-does: antioxidant, perfuming

Hello, our favorite molecule that helps us wake up in the morning and then keeps us going through the day. As a super well-known stimulant from coffee, tea and plenty of other soft drinks, Caffeine needs no introduction. So we will skip right to the part where we talk about what the hell it does in so-so many cosmetic products.

Looking at the research, we were surprised to find how versatile Caffeine is. It is a small, water-loving molecule with pretty good skin penetration abilties. Once in the skin, it has nice antioxidant properties, meaning that it reduces the formation of evil free radicals and it might even be useful in preventing UV-induced skin cancers. 

Retinol - superstar
Also-called: Vitamin A, Form of Retinoids | What-it-does: cell-communicating ingredient
  • Retinol (pure Vitamin A) is probably the most proven anti-aging ingredient available OTC
  • It has to be converted in the skin to retinoic acid to work its magic
  • Once converted, it has the same effect as all-trans-retinoic acid, aka tretinoin
  • A generally accepted ballpark number is that retinol is 10-to-20 times less potent than retinoic acid
  • It makes skin less wrinkled, smoother, firmer and tighter
  • It might also be helpful for acne prone skin as it normalizes keratinization and makes the pores produce less sebum
  • Possible side effects and irritation are also much less than with retinoic acid
  • Do not use whilst pregnant
Read all the geeky details about Retinol here >>

Also-called: Shea Butter | What-it-does: emollient, viscosity controlling

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: Avocado Oil, Persea Americana Oil | What-it-does: antioxidant, emollient | Irritancy: 0 | Comedogenicity: 0-3

The oil coming from the pulp of one of the most nutritious fruits in the world, the avocado. It's loaded with the nourishing and moisturizing fatty acid, oleic (70%) and contains some others including palmitic (10%) and linoleic acid (8%). It also contains a bunch of minerals and vitamins A, E and D

Avocado oil has extraordinary skin penetration abilities and can nourish different skin layers. It's a very rich, highly moisturizing emollient oil that makes the skin smooth and nourished. Thanks to its vitamin E content it also has some antioxidant properties. As a high-oleic plant oil, it is recommended for dry skin

Ascorbic Acid - superstar
Also-called: Vitamin C, L-ascorbic acid | What-it-does: antioxidant, skin brightening, buffering
  • Works best between a concentration of 5-20%
  • Boosts the skin’s own collagen production
  • Fades pigmentation and brown spots
  • If used under sunscreen it boosts its UV protection
  • Extremely unstable and oxidizes very easily in presence of light or air
  • Stable in solutions with water only if pH is less than 3.5 or in waterless formulations
  • Vit E + C work in synergy and provide superb photoprotection
  • Ferulic acid doubles the photoprotection effect of Vit C+E and helps to stabilize Vit C
  • Potent Vit. C serums might cause a slight tingling on sensitive skin
Read all the geeky details about Ascorbic Acid here >>

Also-called: Form of Retinoids | What-it-does: cell-communicating ingredient | Irritancy: 1-3 | Comedogenicity: 1-3

It's an ester form of vitamin A (retinol + palmitic acid) that belongs to the "retinoid family". The retinoid family is pretty much the royal family of skincare, with the queen being the FDA-approved anti-aging ingredient tretinoin. Retinol is also a very famous member of the family, but it's like Prince William, two steps away from the throne. Retinyl palmitate will be then little Prince George, quite far (3 steps) away from the throne. 

By steps, we mean metabolic steps. Tretinoin, aka retinoic acid, is the active ingredient our skin cells can understand and retinyl palmitate (RP) has to be converted by our metabolic machinery to actually do something. The conversion is a 3 step one and looks like this:

Also-called: Vitamin E Acetate | What-it-does: antioxidant | Irritancy: 0 | Comedogenicity: 0

It’s the most commonly used version of pure vitamin E in cosmetics. You can read all about the pure form here. This one is the so-called esterified version. 

According to famous dermatologist, Leslie Baumann while tocopheryl acetate is more stable and has a longer shelf life, it’s also more poorly absorbed by the skin and may not have the same awesome photoprotective effects as pure Vit E. 

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". 

Sodium PCA - goodie
Also-called: Sodium Pyrrolidone Carboxylic Acid | What-it-does: skin-identical ingredient, moisturizer/humectant | Irritancy: 0 | Comedogenicity: 0

PCA stands for Pyrrolidone Carboxylic Acid and though it might not sound like it, it is a thing that can be found naturally in our skin. The sodium salt form of PCA is an important skin-identical ingredient and great natural moisturizer that helps the skin to hold onto water and stay nicely hydrated. 

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.

Also-called: SOD | What-it-does: antioxidant

Superoxide Dismutase - or in short SOD - is the body's smart antioxidant enzyme that protects the cells from highly reactive, cell-damaging superoxide radicals (O2−).

You have probably read the terms "free radicals" and "antioxidants" a thousand times, and you know that free radicals are the evil guys, and antioxidants are the good guys. So superoxide radical is a very common free radical that can cause all kinds of cell damages and superoxide dismutase is an enzyme that catalyzes the conversion of superoxide radicals into molecular oxygen and hydrogen peroxide (btw, this one has to be further converted by other antioxidant enzymes, called catalases).

Squalane - goodie
What-it-does: skin-identical ingredient, emollient | Irritancy: 0 | Comedogenicity: 1

It seems to us that squalane is in fashion and there is a reason for it. Chemically speaking, it is a saturated  (no double bonds) hydrocarbon (a molecule consisting only of carbon and hydrogen), meaning that it's a nice and stable oily liquid with a long shelf life. 

It occurs naturally in certain fish and plant oils (e.g. olive), and in the sebum (the oily stuff our skin produces) of the human skin. As f.c. puts it in his awesome blog post, squalane's main things are "emolliency, surface occlusion, and TEWL prevention all with extreme cosmetic elegance". In other words, it's a superb moisturizer that makes your skin nice and smooth, without being heavy or greasy.

Also-called: Aloe Vera | What-it-does: soothing, moisturizer/humectant

Aloe Vera is one of today’s magic plants. It does have some very nice properties indeed, though famous dermatologist Leslie Baumann warns us in her book that most of the evidence is anecdotal and the plant might be a bit overhyped.

What research does confirm about Aloe is that it’s a great moisturizer and has several anti-inflammatory (among others contains salicylates, polysaccharides, magnesium lactate and C-glucosyl chromone) as well as some antibacterial components. It also helps wound healing and skin regeneration in general. All in all definitely a goodie. 

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). 

We don't have description for this ingredient yet.

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

Allantoin - goodie
What-it-does: soothing | Irritancy: 0 | Comedogenicity: 0

Super common soothing ingredient. It can be found naturally in the roots & leaves of the comfrey plant, but more often than not what's in the cosmetic products is produced synthetically. 

It's not only soothing but it' also skin-softening and protecting and can promote wound healing.

Panthenol - goodie
Also-called: Pro-Vitamin B5 | What-it-does: soothing, moisturizer/humectant | Irritancy: 0 | Comedogenicity: 0

An easy-to-formulate, commonly used, nice to have ingredient that’s also called pro-vitamin B5. As you might guess from the “pro” part, it’s a precursor to vitamin B5 (whose fancy name is pantothenic acid). 

Its main job in skincare products is to moisturise the skin. It’s a humectant meaning that it can help the skin to attract water and then hold onto it. There is also research showing that panthenol can help our skin to produce more lovely lipids that are important for a strong and healthy skin barrier. 

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.

What-it-does: moisturizer/humectant

We don't have description for this ingredient yet.

Algae Extract - goodie

We have to admit that Algae Extract is not our favorite ingredient name. It does comply with the INCI standard (the official list about how ingredients on the product labels have to be called, the thing we help you to decode here :)), but there are about 20 000 different kinds of algae and an extract from them can be made in another 10 000 ways.

So, Algae Extract can be anything from La Mer's "Miracle Broth" to a simple brown algae extract that helps to smooth the hair. The official description in the Europiean Cosmetic Ingredient listing is this: "an extract of various species of Algae; Extract of the Seaweed, Fucus vesiculosus, Furaceae". Its official functions include being a humectant (helps skin to attract water), emollient (makes skin feel smooth and nice) and skin conditioner (a catchall phrase for saying it does something good for the skin).

It's a petroleum derived emollient and thickener. It often comes to the formula as part of an emulsifier, thickener trio (with Polyacrylamide and Laureth-7). This trio is an easy-to-use liquid that helps to create nice, non-tacky gel formulas. 

We don't have description for this ingredient yet.

Also-called: Rosehip Oil | What-it-does: emollient

Though it says fruit oil in its name, the rosehip fruit contains the seeds that contain the oil. So this one is the same as Rosa Canina Seed Oil,  or Rosehip Oil, known for its high omega fatty acid content (linoleic acid - 51%, linolenic acid - 19% and oleic acid - 20%) and skin-regenerative properties

There is a common misconception that rosehip oil contains vitamin C as the fruit itself does, but vitamin C is a water-soluble vitamin hence it is not contained in the oil. The antioxidant and regenerative properties of the oil probably come from the oil-soluble tocopherols (vitamin E) and carotenoids (pro-vitamin A). Read more here

What-it-does: emollient, soothing

We don't have description for this ingredient yet.

Also-called: Green Tea | What-it-does: antioxidant, soothing
  • Green tea is one of the most researched natural ingredients
  • The active parts are called polyphenols, or more precisely catechins (EGCG being the most abundant and most active catechin)
  • There can be huge quality differences between green tea extracts. The good ones contain 50-90% catechins (and often make the product brown and give it a distinctive smell)
  • Green tea is proven to be a great antioxidant, UV protectant, anti-inflammatory, anticarcinogenic and antimicrobial
  • Because of these awesome properties green tea is a great choice for anti-aging and also for skin diseases including rosacea, acne and atopic dermatitis
Read all the geeky details about Camellia Sinensis Leaf Extract here >>

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. 

Also-called: Sunflower Oil | What-it-does: emollient | Irritancy: 0 | Comedogenicity: 0

Sunflower does not need a big intro as you probably use it in the kitchen as cooking oil, or you munch on the seeds as a healthy snack or you adore its big, beautiful yellow flower during the summer - or you do all of these and probably even more. And by even more  we mean putting it all over your face as sunflower oil is one of the most commonly used plant oils in skincare.

It’s a real oldie: expressed directly from the seeds, the oil is used not for hundreds but thousands of years. According to The National Sunflower Association, there is evidence that both the plant and its oil were used by American Indians in the area of Arizona and New Mexico about 3000 BC. Do the math: it's more than 5000 years – definitely an oldie.

What-it-does: soothing

We don't have description for this ingredient yet.

What-it-does: buffering

It’s a little helper ingredient that helps to set the pH of a cosmetic formulation to be just right.

Also-called: Fermented Radish Root | What-it-does: antimicrobial/antibacterial, preservative

It's an alternative, natural preservative that comes from radishes fermented with Leuconostoc kimchii, a lactic acid bacteria that has been used to make traditional Korean dish, kimchi. During the fermentation process, a peptide is secreted from the bacteria that has significant antimicrobial properties

It is one of the more promising natural preservatives that can be used even alone (recommended at 2-4%), but it's not as effective as more common alternatives, like parabens or phenoxyethanol

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. 

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: 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 | Irritancy: 0 | Comedogenicity: 2

It’s a little helper ingredient that helps to set the pH of a cosmetic formulation to be just right. It’s very alkaline (you know the opposite of being very acidic): a 1% solution has a pH of around 10.

It does not have the very best safety reputation but in general, you do not have to worry about it. 

We don't have description for this ingredient yet.

What-it-does: viscosity controlling

It's a film-forming and thickening polymer (a large molecule composed of many repeated subunits) that comes to the formula usually as part of an emulsifier, thickener trio (with C13-14 Isoparaffin and Laureth-7, trade named Sepigel 305). This trio is an easy-to-use liquid that helps to create nice, non-tacky gel formulas

What-it-does: emulsifying, surfactant/cleansing | Irritancy: 0 | Comedogenicity: 0

It's a common little helper ingredient that helps water and oil to mix together. Also, it can help to increase the solubility of some other ingredients in the formula. 

Also-called: Omega-9 fatty acid | What-it-does: emollient, emulsifying

A common fatty acid that can be found in lots of plant oils. Its name, "oleic", means derived from olive oil, a plant oil rich in oleic acid, but avocado, macadamia and marula oils, just to name a few, are also oleic rich.

Its chemical structure is monounsaturated, meaning it has one double bond (cis-9) that makes it less kinky than polyunsaturated fatty acids with multiple double bonds. Less kinkiness means that oleic acid and OA-rich oils are a bit thicker and heavier than their LA-rich siblings.

What-it-does: emollient, emulsifying

We don't have description for this ingredient yet.

A not-very-interesting helper ingredient that is used as an emulsifier and/or surfactant. Comes from a coconut oil derived fatty alcohol, lauryl alcohol.

We don't have description for this ingredient yet.

What-it-does: chelating

An abbreviation that pops up on a lot of ingredient lists. It stands for EthyleneDiamineTetraacetic Acid and it's a famous molecule for being an excellent chelating agent, i.e. a molecule that can bind to metal ions (coming usually from water) and make them harmless in a cosmetic formula. With a chelating agent, cosmetic formulas stay nice longer.

EDTA is an acid molecule and its salt versions are even more often used, such as the super common Disodium EDTA

What-it-does: solvent

It's a type of glycol that - according to the manufacturer - is an extremely good replacement for other glycols like propylene or butylene glycol. Its main job is to be a solvent, but it has also very good antimicrobial properties and acts as a true preservative booster. Also helps with skin hydration without stickiness or tacky feel.

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.

What-it-does: moisturizer/humectant, solvent, viscosity controlling | Irritancy: 0 | Comedogenicity: 0
  • It's a helper ingredient that improves the freeze-thaw stability of products
  • It's also a solvent, humectant and to some extent a penetration enhancer
  • It has a bad reputation among natural cosmetics advocates but cosmetic scientists and toxicology experts do not agree (read more in the geeky details section)
Read all the geeky details about Propylene Glycol here >>

What-it-does: preservative

It's one of those things that help your cosmetics not to go wrong too soon, aka a preservative. It’s not a strong one and doesn’t really work against bacteria, but more against mold and yeast. To do that it has to break down to its active form, sorbic acid. For that to happen, there has to be water in the product and the right pH value (pH 3-4). 

But even if everything is right, it’s not enough on its own. If you see potassium sorbate you should see some other preservative next to it too.

What-it-does: preservative

A helper ingredient that helps to make the products stay nice longer, aka preservative. It works mainly against fungi. 

It’s pH dependent and works best at acidic pH levels (3-5). It’s not strong enough to be used in itself so it’s always combined with something else, often with potassium sorbate.

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. 

Alcohol - icky
Also-called: Ethanol | 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: 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 solvent
Normal (well kind of - it's purified and deionized) water. Usually the main solvent in cosmetic products. [more]
what‑it‑does emollient | emulsifying
irritancy, com. 0, 1-2
Waxy, white, solid stuff that helps water and oil to mix together and leaves the skin feeling soft and smooth. [more]
what‑it‑does emollient
A very common emollient that makes your skin feel nice and smooth. Comes from coconut oil and glycerin, it’s light-textured, clear, odorless and non-greasy. [more]
what‑it‑does emollient | viscosity controlling
irritancy, com. 2, 2
A fatty (the good, non-drying kind of) alcohol that makes your skin feel smooth and nice (emollient), helps to thicken up products and also helps water and oil to blend (emulsifier).
what‑it‑does surfactant/cleansing
irritancy, com. 0-1, 0-3
what‑it‑does emollient | viscosity controlling | emulsifying | perfuming
irritancy, com. 0, 0-2
The yellow solid stuff produced by honey bees to build their honeycomb. As for skincare, it's used as an emollient and thickening agent. [more]
what‑it‑does antioxidant | perfuming
The well-known stimulant from coffee. It has nice antioxidant properties and can improve the microcirculation. Might be helpful for dark circles, puffy eyes, as well as cellulite and hair loss. [more]
what‑it‑does cell-communicating ingredient
Vitamin A - the most proven anti-aging ingredient available OTC that can smooth wrinkles and make skin firmer. It might also be useful for acne-prone skin as it normalizes keratinization. [more]
what‑it‑does emollient | viscosity controlling
Shea butter that's considered to be a magic moisturizer and emollient. It is also soothing and rich in antioxidants. [more]
what‑it‑does antioxidant | emollient
irritancy, com. 0, 0-3
Avocado oil - a highly moisturizing, rich emollient oil that is loaded with fatty acids (oleic - 70%) and vitamin A, E and D. [more]
what‑it‑does antioxidant | skin brightening | buffering
Pure Vitamin C. A skincare superstar that is clinically proven to boost collagen production (in 5-20% concentration), fade hyperpigmentation and boost UV protection under sunscreen. Also, it's extremely unstable and hard to formulate. [more]
what‑it‑does cell-communicating ingredient
irritancy, com. 1-3, 1-3
An ester form of vitamin A (retinol + palmitic acid) that is pretty much the least effective member of the retinoid family. Its anti-aging effects are quite questionable as well as its behavior in the presence of UVA light. (Use it at night if possible!) [more]
what‑it‑does antioxidant
irritancy, com. 0, 0
A form of vitamin E that works as an antioxidant. Compared to the pure form it's more stable, has longer shelf life, but it's also more poorly absorbed by the skin. [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 skin-identical ingredient | moisturizer/humectant
irritancy, com. 0, 0
It's an important skin-identical ingredient and great natural moisturizer that helps the skin to hold onto water and stay nicely hydrated. [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 antioxidant
Superoxide Dismutase - or in short SOD - is the body's smart antioxidant enzyme that protects the cells from highly reactive, cell-damaging superoxide radicals (O2−). You have probably read the terms "free radicals" [more]
what‑it‑does skin-identical ingredient | emollient
irritancy, com. 0, 1
An emollient and natural moisturizer that can be found also in the sebum (oily stuff our skin produces). It leaves a nice non-greasy, non-heavy feeling on the skin. [more]
what‑it‑does soothing | moisturizer/humectant
The famous aloe vera. A great moisturizer and anti-inflammatory ingredient that also helps wound healing and skin regeneration. [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 moisturizer/humectant | emollient
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]
what‑it‑does soothing
irritancy, com. 0, 0
Super common soothing ingredient. It can be found naturally in the roots & leaves of the comfrey plant, but more often than not what's in the cosmetic products is produced synthetically. It's not only soothing but it' [more]
what‑it‑does soothing | moisturizer/humectant
irritancy, com. 0, 0
Pro-Vitamin B5 is a goodie that moisturises the skin, has anti-inflammatory, skin protecting and wound healing properties. [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 moisturizer/humectant
what‑it‑does emollient | moisturizer/humectant
An extract that comes from one or more of the 20 000 kinds of algae out there. In general algae extracts serve as moisturizing, emollient and thickening agents, and many of them also have additional anti-aging properties. [more]
what‑it‑does emollient | viscosity controlling | solvent
A petroleum-derived emollient and thickener. It often comes to the formula as part of an emulsifier, thickener trio. [more]
what‑it‑does emollient
Though it says fruit oil in its name, the rosehip fruit contains the seeds that contain the oil. So this one is the same as Rosa Canina Seed Oil,  or Rosehip Oil, known for its high omega fatty acid content (linoleic acid - 51%, linolenic acid - 19% and oleic acid - 20%) and skin-regenerative properties.  [more]
what‑it‑does emollient | soothing
what‑it‑does antioxidant | soothing
Green Tea - one of the most researched natural ingredients that contains the superstar actives called catechins. It has proven antioxidant, anti-inflammatory, antimicrobial and anticarcinogenic properties. [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
irritancy, com. 0, 0
Sunflower Oil - it's a great emollient that protects & enhances the skin barrier. [more]
what‑it‑does soothing
what‑it‑does buffering
It’s a little helper ingredient that helps to set the pH of a cosmetic formulation to be just right. [more]
what‑it‑does antimicrobial/antibacterial | preservative
It's an alternative, natural preservative that comes from radishes fermented with Leuconostoc kimchii, a lactic acid bacteria that has been used to make traditional Korean dish, kimchi. [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 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 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
irritancy, com. 0, 2
Helps to set the pH of a cosmetic formulation to be right. It’s very alkaline. [more]
what‑it‑does antimicrobial/antibacterial
what‑it‑does viscosity controlling
A film-forming and thickening polymer (a large molecule composed of many repeated subunits) that comes to the formula usually as part of an emulsifier, thickener trio. [more]
what‑it‑does emulsifying | surfactant/cleansing
irritancy, com. 0, 0
It's a common little helper ingredient that helps water and oil to mix together. Also, it can help to increase the solubility of some other ingredients in the formula. 
what‑it‑does emollient | emulsifying
A common fatty acid that can be found in lots of plant oils. Its name, "oleic", means derived from olive oil, a plant oil rich in oleic acid, but avocado, macadamia and marula oils, just to name a few, are also oleic rich. Its chemical structure is monounsaturated, meaning it has one double bond (cis-9) that makes it less kinky than polyunsaturated fatty acids with multi [more]
what‑it‑does emollient | emulsifying
what‑it‑does emulsifying | surfactant/cleansing
A not-very-interesting helper ingredient that is used as an emulsifier and/or surfactant. Comes from a coconut oil derived fatty alcohol, lauryl alcohol. [more]
what‑it‑does antioxidant | viscosity controlling
what‑it‑does chelating
An abbreviation that pops up on a lot of ingredient lists. It stands for EthyleneDiamineTetraacetic Acid and it's a famous molecule for being an excellent chelating agent, i.e. a molecule that can bind to metal ions (coming usually from water) and make them harmless in a cosmetic formula. [more]
what‑it‑does solvent
A type of glycol. Its main job is to be a solvent, but it has also very good antimicrobial properties and acts as a true preservative booster. [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 moisturizer/humectant | solvent | viscosity controlling
irritancy, com. 0, 0
A common glycol that improves the freeze-thaw stability of products. It's also a solvent, humectant and to some extent a penetration enhancer. [more]
what‑it‑does preservative
A not so strong preservative that doesn’t really work against bacteria, but more against mold and yeast. [more]
what‑it‑does preservative
A preservative that works mainly against fungi. Has to be combined with other preservatives. [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 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 preservative
Pretty much the current IT-preservative. It’s safe and gentle, and can be used up to 1% worldwide. [more]