Dr. Pepti

Peptide Volume Water Glow Serum

A synthetic liquid oil that can replace mineral oil or silicone oils in the cosmetic formulas. There are different grades depending on the molecular weight ranging from very light, volatile, non-residue leaving ones to more substantial, slight residue leaving ones.

Apart from leaving the skin soft and smooth (emollient), it's also used as a waterproofing agent in sunscreens or makeup products and as a shine enhancer in lip gloss formulas. 

We don't have description for this ingredient yet.

We don't have description for this ingredient yet.

We don't have description for this ingredient yet.

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. 

• 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

A super commonly used 5 unit long, cyclic structured silicone that is water-thin and does not stay on the skin but evaporates from it (called volatile silicone). Similar to other silicones, it gives skin and hair a silky, smooth feel. 

It's often combined with the non-volatile (i.e. stays on the skin) dimethicone as the two together form a water-resistant, breathable protective barrier on the skin without a negative tacky feel.

A really multi-functional helper ingredient that can do several things in a skincare product: it can bring a soft and pleasant feel to the formula, it can act as a humectant and emollient, it can be a solvent for some other ingredients (for example it can help to stabilize perfumes in watery products) and it can also help to disperse pigments more evenly in makeup products. And that is still not all: it can also boost the antimicrobial activity of preservatives. 

• It’s naturally in our skin and behaves there like a sponge
• It can bind up to 1000 times its own weight in water
• It is a big molecule from repeated subunits (polymer) so different molecular weight versions exist (unfortunately there is no way to determine MW from INCI list only)
• High-molecular-weight-HA (>500 kDa) is an excellent surface hydrator, skin protectant and can act as an osmotic pump helping water-soluble actives to penetrate deeper into the skin
• Low-molecular-weight-HA (< 500 kDa) can hydrate the skin somewhat deeper though it is still a big molecule and works mainly in the epidermis (outer layer of the skin)
• Low-molecular-weight-HA might also help the skin to repair itself by increasing its self-defense (~ 200kDa used in the study)
• Ultra-low-molecular-weight-HA (<50kDa) is a controversial ingredient and might work as a pro-inflammatory signal molecule

Hydrolyzed Hyaluronic Acid is a low molecular weight, chemically chopped up version of the naturally big molecule and current IT-moisturizer, Hyaluronic Acid (HA). 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 retain water, making it plump and elastic. As HA is a polymer, the subunits can be repeated many times (as a high-molecular-weight version), or just a few times (as a low-molecular-weight version).

We wrote in detail at HA about how different molecular weight versions do different things both as a component of the skin and as a skincare ingredient, so click here and read about all the details. Hydrolyzed Hyaluronic Acid can also come in different molecular-weight versions with different properties:

Expand to read more

It's a super small, chemically chopped up version of sodium hyaluronate. Its trade name is miniHA, and its molecular weight is 10 kDa. This counts as really tiny given that "normal" HA has a molecular weight of 0.5-2 million Da.

To be honest, low molecular weight (LMW), and especially this ultra-low molecular weight HA is a controversial ingredient. On the upside, it can penetrate the skin better (though 10kDa still counts as big!) and might be able to moisturize the deeper layers of the skin where normal HA cannot get. Also, according to the manufacturer of miniHA, it has better antioxidant activity than a 1.6MDa version HA and it also has better sun protection and after-sun repair abilities than the higher MW versions. It also works in synergy with higher molecular weight versions, and the combination of 0.1% 1.45MDa-HA + 0.1% 380 kDa-HA + 0.1% miniHA hydrated the skin significantly better than 0.3% 1.45MDa-HA alone.

Expand to read more

It’s the - sodium form - cousin of the famous NMF, hyaluronic 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". 

Expand to read more

We don't have description for this ingredient yet.

We don't have description for this ingredient yet.

It's a special "cross-linked" from of IT-moisturizer, hyaluronic acid (HA). Cross-linked means that "normal" HA pieces (1-2 million Da molecular weight) are chemically bound togeather to create a big, "infinite" mesh.

The special HA mesh has a remarkable water-binding capacity, 5 times more than the already crazy water-binding capacity of "normal" HA. This water filled crosslinked HA gel forms a smooth film on the skin and continuously delivers the bound water, so it gives long-term moisturizing benefits.

Expand to read more

Sodium Acetylated Hyaluronate is a variation of current IT moisturizer, Hyaluronic acid, where some water-loving -OH groups are replaced by amphipathic (partly water-loving and partly water-hating) acetyl groups. The modified molecule is claimed to have even better moisture retention ability than normal HA and better affinity to the skin surface. 

The better affinity comes from the acetyl groups that act as tiny "anchors" to attach the HA molecule to the skin. Staying on top of the skin better and longer means longer-lasting surface hydration and improved elasticity. It is also less sticky and more cosmetically elegant than normal HA, so no wonder the nickname of this molecule is super hyaluronic acid. 

A semi-essential (infants cannot synthesize it, but adults can) amino acid that is one of the primary building blocks of hair keratin and skin collagen. It's a natural moisturizing factor, a skin hydrator and might also help to speed up wound healing. 

Arginine usually has a positive charge (cationic) that makes it substantive to skin and hair (those are more negatively charged surfaces) and an excellent film former.  Thanks to the positive charge, it also creates a complex with AHAs (AHAs like to lose a hydrogen ion and be negatively charged, so the positive and the negative ions attract each other) that causes a "time-release AHA effect" and reduces the irritation associated with AHAs. 

A non-essential amino acid (the building blocks of skin proteins, like collagen or elastin), that the body can produce itself, but its production decreases with age. When you put it all over your face, it works as a moisturizer and maybe more. 

According to great skincare blog Futurederm, glycine might help with wound healing and tissue repair and when used together with other amino acids, leucine and proline it might improve wrinkles. 

Expand to read more

Glutamic acid is a little molecule and non-essential (our body can synthesize it) amino acid with the important job of being a neurotransmitter in the human body meaning that it helps your nervous system work correctly. 

As for what it's doing in cosmetics, Glutamic acids' main thing (similar to other amino acids) is being a humectant moisturizer and skin-conditioning agent (sidenote: if you attach lots of glutamic acid molecules, you get polyglutamic acid that is claimed to be a better than hyaluronic acid humectant). It also seems to affect skin barrier repair, however, it is not clear-cut in which direction.

Expand to read more

We don't have description for this ingredient yet.

We don't have description for this ingredient yet.

It's a little helper ingredient coming from corn, rice or potato starch that can help to keep skin mat (absorbent), to stabilise emulsions, and to keep the product together (binding). 

We don't have description for this ingredient yet.

Ectoin is a surprisingly well-researched, multi-functional active that can do from pollution & light protection to skin hydration, soothing, and barrier repair, several things to your skin. 

It is an extremolyte, a small stress-protection molecule that protects microorganisms living under extreme conditions such as salt lakes, hot springs, arctic ice, the deep sea, or deserts. It was discovered in 1985 in a microorganism living in a salt lake in the Egyptian desert. 

Expand to read more

If you see a cosmetic product that claims that it has "Botox-like effect" then two things are almost certain: one, the product overpromises and two, it contains Argireline. 

So this one is the famous peptide that's marketed by its manufacturer as the "Botox in a jar". The basis for this claim is that it targets the same wrinkle forming mechanism (wrinkles caused by facial muscle movement) as Botox, but the way it works is very different. In addition, the extent to which it can prevent muscles from contracting (and to smooth wrinkles) is very different (otherwise why would anyone use still Botox?). 

Expand to read more

• GHK-Cu is a copper-peptide complex found naturally in yucky bodily fluids (plasma, saliva, and urine)
• It has unique wound healing properties by stimulating the breakdown of unhealthy, too large collagen in scar tissue and stimulating nice and healthy collagen production afterwards
• It stimulates the production of several important skin-identical ingredients (e.g. collagen, elastin, and glycosaminoglycans)
• It has significant anti-inflammatory and antioxidant effect
• There are a few promising studies showing GHK-Cu can improve skin elasticity, clarity, firmness and reduce lines and wrinkles
• It can improve hair growth by enlarging hair follicles (and bigger follicles produce longer, thicker hair)
• There are some urban legends about possible overdosing or facial hair problems (read more in geeky details)

A small, three amino acid (glycine-histidine-lysine or GHK) peptide that is famous for being a type I collagen fragment. The theory behind collagen-fragment peptides is that when collagen naturally breaks down in the skin, the resulting peptide fragments signal to the skin that it should get to work and create some nice, new collagen.

Adding in collagen fragment peptides, like GHK, might trick the skin into thinking that collagen has broken down and it's time to create some more. So Tripeptide-1 is believed to be able to stimulate collagen production in the skin, and more collagen means fewer wrinkles and younger looking skin. FYI; Tripeptide-1 is the same peptide that can be found in the famous Matrixyl 3000, but in Matrixyl a palmitic acid is attached to it to increase its oil solubility and thus skin penetration.

Expand to read more

We don't have description for this ingredient yet.

A four amino acid peptide with the amino sequence of glycine-glutamine-proline-arginine. It is attached to palmitic acid (a fatty acid)  to increase oil solubility and skin penetration. 

It works by reducing the production of the signal molecule, interleukin-6 (IL-6) which promotes inflammation in the skin and less inflammation means slower degradation of important things (like collagen) that results in younger looking skin for a longer time. 

Expand to read more

A really famous peptide that is part of Matrixyl 3000, the most sold peptide complex in the word. Before we go and find out what the big deal with Matrixyl 3000 is, let's just focus on Palmitoyl Tripeptide-1 itself for a bit.

It's a small three amino acid (they are the building blocks of all proteins) peptide with the amino sequence of glycine-histidine-lysine, or GHK. GHK is attached to palmitic acid (a fatty acid) to increase oil solubility and skin penetration. 

Expand to read more

A six amino acid peptide that is claimed to improve firmness and skin tone. Its amino acid sequence is Val-Gly-Val-Ala-Pro-Gly that is also called the "spring fragment" and is repeated six times in the important skin protein, elastin molecule.

The manufacturer made a double-blind, one-month long clinical study on 10 women and found that twice a day application of 4%  Biopeptide El improved skin firmness by 33% and skin tone by 20%. 

A tripeptide (three amino acids attached to each other: Lys-Val-Lys) that's claimed to protect and boost collagen and improve skin texture.

The manufacturer did an in-vivo (made on real people) study with 45 volunteers and found that used twice daily for 84 days 1% and 2.5% Syn-Coll reduces the appearance of wrinkles by 7 and 12% respectively. In another study (also by the manufacturer) with 33 female Chinese volunteers, 77% of the participants felt that Syn-Coll visibly improved the firmness and elasticity of the skin after 4 weeks. What's more, 60% of the participants also noticed a reduction in the look of the pore size also after 4 weeks of treatment. 

A newer and, molecule-wise, somewhat bigger version of the famous "Botox-like" peptide called Acetyl Hexapeptide-8 or Argireline. Just like Argireline, Acetyl Octapeptide-3 is also claimed to influence the muscle contraction process that results in a more relaxed and line-free face, especially around the forehead and the eyes.  

While Argireline counts as a pretty well-proven peptide, with multiple studies confirming its anti-wrinkle efficacy, we cannot say the same for Acetyl Octapeptide-3. What we have is the manufacturer's claim that comparing 10% Argireline with 10% SNAP-8 solution (that means 0.005% pure peptide powder) the SNAP-8 peptide did a bit better as it reduced wrinkles by 34.98% vs 27.05% reduction for Argireline (twice a day use for 28 days on 17 women). 

Expand to read more

A relatively new, four amino acid peptide that promises to help combat hair loss alongside red clover extract as part of the trademarked technology Capixyl. 

The main thing of  Acetyl Tetrapeptide-3 is to stimulate the synthesis of key Extra Cellular Matrix (aka ECM, the gooey stuff between cells that make up the framework of our skin) components in the scalp.  According to the manufacturer’s lab studies, the expression of type III collagen increased by 65% and the expression of laminins (anchoring proteins found in the ECM) was up a massive 285%, resulting in a stronger ECM bed for hair anchoring.

Expand to read more

A four amino acid peptide that is claimed to improve puffy eye bags via its anti-oedema and anti-glycation effects.

To back this claim up, the manufacturer created an in-vivo study with 20 volunteers using 10% of EYESERYL (that comes down to 0.01% (!) of the pure peptide) and found that by day 15, 70% of the volunteers improved, while 95% of the volunteers improved by the end of the study (60 days). About third of them improved only slightly, third of them showed an ok improvement and third showed a good improvement. They also have pretty convincing before and after photos, so we can tell you that for the lucky ones, the improvement can be real and visible.

Expand to read more

This awfully long named ingredient is, in fact, a pretty small molecule. It's a tripeptide (a three amino acid peptide)  with molecular weight less than 500 Da, meaning that it's small enough to penetrate nicely and easily into the skin.

It belongs to the "Botox in a jar" type of peptides (similar to Argireline or Leuphasyl) targeting wrinkles caused by facial movements, like laughter lines or crow’s feet. According to the manufacturer's in-vivo (made on real people) studies, 4% Syn-Ake used for 28 days resulted in 21% smoother and 15-20% less wrinkled skin with max values up to 52%. The smoothing effect was measurable on 80% of the volunteers, while the wrinkle reduction effect was evident on 73%.

A tiny peptide with only two amino acids (amino acids are the building block of proteins, and peptides are a few amino acids attached together), Valine and Tryptophan. It's part of a 3 actives complex called Eyeliss (with HMC and Palmitoyl Tetrapeptide-7) that's supposed to fight under-eye bags. 

The manufacturer claims that this dipeptide in Eyeliss can increase lymphatic circulation and the three actives together represent a "global approach to treating puffy eyes". The clinical study of the manufacturer with 20 people and 3% Eyeliss showed improvement after 56 days for 70% of the participants.

We don't have description for this ingredient yet.

An anti-aging peptide that can visibly reduce the length and depth of wrinkles, at least according to its manufacturer. In vitro (meaning it was done in the lab, not on real people) studies show that it enhances epidermal regeneration, collagen type I and III synthesis as well as the synthesis of other important skin proteins. 

We don't have description for this ingredient yet.

A pretty famous and better-researched peptide consisting of five amino acids (the building blocks of all proteins). It was created in a joint effort by the French ingredient supplier, Sederma and the cosmetics industry big shot, Procter&Gamble.

The amino acid sequence of the peptide is lysine–threonine–threonine–lysine–serine (KTTKS). Sometimes, it's also called collagen pentapeptide, as it's a subfragment of skin-structure-giving type I collagen. The KTTKS amino sequence is then attached for better oil solubility and skin penetration to palmitic acid and BOOM; we get Palmitoyl Pentapeptide-4. 

Expand to read more

We don't have description for this ingredient yet.

We don't have description for this ingredient yet.

Also called vitamin H, biotin is the main component of many enzymes in our body. A nice ingredient to take as a supplement for stronger nails and hair. When you do not take it as a supplement its effects are a bit more questionable but according to manufacturer info it can smooth the skin and strengthen the hair.

We don't have description for this ingredient yet.

The chemically chopped up version of the big protein molecule, collagen. It is often derived from fish or bovine sources and works as a nice moisturizer and humectant that helps the skin to hold onto water.  

To understand a bit more what Hydrolyzed Collagen is, you have to know that proteins are large chains of amino acids connected with so-called peptide bonds. These bonds can be broken up when a water molecule is added and the resulting thing is a mix of shorter length amino acids, also called peptides. So Hydrolyzed Collagen is not really collagen, it is rather an undefined and varying mix of largish peptides. Based on a manufacturer's data, the whole, soluble collagen has an average molecular weight of 300 000 Da, while this chopped up mixture has an average MW of 12 000 Da (still pretty big). 

Expand to read more

We don't have description for this ingredient yet.

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. 

Expand to read more

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.

We don't have description for this ingredient yet.

We don't have description for this ingredient yet.

A light-feeling, volatile (meaning it does not absorb into the skin but evaporates from it) silicone that gives skin a unique, silky and non-greasy feel. It has excellent spreading properties and leaves no oily residue or build-up. 

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.

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

We don't have description for this ingredient yet.

We don't have description for this ingredient yet.

A very common water-loving surfactant and emulsifier that helps to keep water and oil mixed nicely together. 

It's often paired with glyceryl stearate - the two together form a super effective emulsifier duo that's salt and acid tolerant and works over a wide pH range. It also gives a "pleasing product aesthetics", so no wonder it's popular.

A vegetable origin (coconut/palm kernel oil, glucose) cleansing agent that gives moderate to high stable foam. It's also biodegradable and mild to the skin.

A sugar beet-derived amino acid derivative with nice skin protection and moisturization properties. Betaine's special thing is being an osmolyte, a molecule that helps to control cell-water balance.  It is also a natural osmoprotectant, meaning that it attracts water away from the protein surface and thus protects them from denaturation and increases their thermodynamic stability. 

It also gives sensorial benefits to the formula and when used in cleansers, it helps to make them milder and gentler. 

We don't have description for this ingredient yet.

A superabsorbent polymer (big molecule from repeated subunits) that has crazy water binding abilities. Sometimes its referred to as "waterlock" and can absorb 100 to 1000 times its mass in water. 

As for its use in cosmetic products, it is a handy multi-tasker that thickens up water-based formulas and also has some emulsifying and emulsion stabilizing properties. 

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%.

It's the chemically chopped up version of normal lecithin. Most often it's used to create liposomes and to coat and stabilize other ingredients. 

A hydrocarbon-based emollient that can come in different viscosities from silky-light through satiny-smooth to luxurious, rich. It forms a non-occlusive film on the surface of the skin and brings gloss without greasiness to the formula. It's a very pure and hypoallergenic emollient that's also ideal for baby care products. 

A fatty acid that can be found naturally in the skin. In fact, it's the most common saturated fatty acid found in animals and plants.

As for skincare, it can make the skin feel nice and smooth in moisturizers (emollient) or it can act as a foam building cleansing agent in cleansers. It's also a very popular ingredient in shaving foams. 

A common multi-tasker fatty acid. It makes your skin feel nice and smooth (emollient), gives body to cream type products and helps to stabilize water and oil mixes (aka emulsions).

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.  

Expand to read more

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.

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.

If you have spotted ethylhexylglycerin on the ingredient list, most probably you will see there also the current IT-preservative, phenoxyethanol. They are good friends because ethylhexylglycerin can boost the effectiveness of phenoxyethanol (and other preservatives) and as an added bonus it feels nice on the skin too.

Also, it's an effective deodorant and a medium spreading emollient. 

A little helper ingredient that can be a thickener, a humectant, a foam booster, an adhesion promoter and a filler. It's a blend of polysaccharides that helps to moisturize and soften the skin. 

Adenosine is an important little compound in our body that has a vital cell-signalling role. Research on smearing it on our face is also promising and shows so far a couple of things:

• It can help with wound healing
• It’s a good anti-inflammatory agent
• It might even help with skin’s own collagen production and improve skin firmness and elasticity
• It helps with barrier repair and protection
• It might be even useful for the hair helping with hair thickness and hair growth

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.

We don't have description for this ingredient yet.

Glyceryl acrylate/acrylic acid copolymer is the fancy word for a common polymer (big molecule from repeated subunits), namely polyacrylic acid (aka carbomer when it comes to cosmetics) with glycerin attached to it in some places.

The main thing of this polymer is that it forms a hydrogel (trade named Lubrajel) that can sit on top of the skin and provide moisturizing, water-soluble ingredients such as glycerin to the skin. Think of it as a very thin, wet sponge that a cosmetic manufacturer can fill with good ingredients for your skin. It also works as a thickening agent (remember, it is a carbomer type of molecule), and can provide the skin with a nice slippery feel. It can also draw water to the skin (thank you, pendant glycerol groups!), providing skin hydration.

Expand to read more

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.

We don't have description for this ingredient yet.

We don't have description for this ingredient yet.

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.

A fancy name for sugar. Luckily when you put it on your skin it's good for you not like when you eat it. :) It has water-binding properties, which means that it helps to keep your skin nice and hydrated. 

Usually, a glycerin or glycol based extract of honey that has similar properties to pure honey, i.e. moisturizing, soothing and antibacterial magic properties.

If you wanna know more about honey in cosmetics, we have a shiny explanation here >>

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.