Hyper Vitamin C 23 Serum 20ml
Isntree Hyper Vitamin C 23 Serum is a 20ml serum with Ethyl Ascorbyl Ether, used after toner and before moisturizer, morning and evening.
No reviews yet20ml
$7.50 per 10 ml
- Korean-market formula
- Ships from California or direct from Korea
- Korean barcode and batch code intact
- Suited to
- Dehydrated skinSensitive skinDull, uneven tone
- Helps with
- Shoppers looking for Ethyl Ascorbyl Ether in a serumRoutines that want Ethyl Ascorbyl Ether and Adenosine in one stepFilling the serum step with a Korean-market formula
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- 30-day returns
- Free US shipping on orders of $100 or more
- Tracked delivery to your door
Key benefits
- Ethyl Ascorbyl Ether, the vitamin this serum is built around
- Adenosine on the same list, an active
- Ascorbic Acid and Tocopherol on the same list, antioxidants
- Gardenia Florida Fruit Extract on the same list, a plant extract
- Polyglycerin-3 and Hydroxyethyl Urea further down the same list
- Panthenol further down the same list
Key actives
2Ascorbic Acidantioxidant
Ascorbic Acid is pure vitamin C, the most researched form and also the least stable: it needs a low pH and airtight packaging to stay active. It is an antioxidant used for the look of dullness and uneven tone. It is named second on this serum's list, alongside Ethyl Ascorbyl Ether.
8Ethyl Ascorbyl Ethervitamin
A vitamin C derivative with an ethyl group on the third position, the same molecule usually written 3-O-Ethyl Ascorbic Acid. The ether makes it far more stable in water than pure ascorbic acid. The name on the box points at it, and it is named eighth on this serum's own ingredient list.
12Adenosineactive
Adenosine is a nucleoside that Korea's own cosmetic authority recognises as a wrinkle-care functional ingredient, which is why it appears on so many Korean lists at a low level. It is used for the look of fine lines and is stable and well tolerated. The panel names it twelfth on this serum's list, beside Ethyl Ascorbyl Ether.
15Gardenia Florida Fruit Extractplant extract
Gardenia Fruit Extract is the traditional East Asian yellow dye plant. In skincare it is used as an antioxidant extract, and it can tint a formula. The panel names it fifteenth on this serum's list, beside Ethyl Ascorbyl Ether.
17Tocopherolantioxidant
Tocopherol is vitamin E. It is an oil-soluble antioxidant that protects the oils in a formula from going rancid and works on skin as an emollient, and it is regularly paired with vitamin C because each keeps the other going for longer. The panel names it seventeenth on this serum's list, beside Ethyl Ascorbyl Ether.
Inside the formula
Inside the formula
- 2Ascorbic Acid
- 8Ethyl Ascorbyl
- 12Adenosine
- 15Gardenia Florida
- 17Tocopherol
Where each key active sits on the declared ingredient list, by entry number. Position is proportion: the further forward, the larger its share.
Isntree Hyper Vitamin C 23 Serum 20ml
Where does this serum go in my routine?
After toner and before moisturizer, morning and evening. Anything thinner than a serum goes on before it, and anything richer goes on after. If you are adding it to a routine you already like, give it a week on its own first, so what you see is the Ethyl Ascorbyl Ether and not three changes at once.
What else is on the list besides Ethyl Ascorbyl Ether?
Adenosine, Ascorbic Acid and Tocopherol. The order they are printed in on this serum's panel is the order on the box, so you can see where Ethyl Ascorbyl Ether sits relative to them. Further down the same panel: Gardenia Florida Fruit Extract, Polyglycerin-3 and Hydroxyethyl Urea.
Not on the ingredient list below: fragrance or parfum, denatured or SD alcohol, essential oils, silicones, parabens, sulfate surfactants, mineral oil or petrolatum and added color.
Full INCI (17): Water, Ascorbic Acid(23%), Propanediol, Betaine, 1,2-Hexanediol, Polyglycerin-3, Tromethamine, Ethyl Ascorbyl Ether, Hydroxyethyl Urea, Betula Platyphylla Japonica Juice, Ethylhexylglycerin, Adenosine, Disodium EDTA, Panthenol, Gardenia Florida Fruit Extract, Dextrin, Tocopherol
17 of 17 explained
- Water solvent
- Water is the base almost every serum, toner and cream is built on. It dissolves the water-loving ingredients and sets how light the finished texture feels. On an INCI list it is usually first, which only means it is the largest single ingredient by weight.
- Ascorbic Acid(23%) antioxidant
- Ascorbic Acid is pure vitamin C, the most researched form and also the least stable: it needs a low pH and airtight packaging to stay active. It is an antioxidant used for the look of dullness and uneven tone.
- Propanediol humectant
- Propanediol is a plant-derived glycol used in place of propylene glycol. It hydrates, carries actives into solution, and gives a lighter, less sticky slip than glycerin at the same strength.
- Betaine humectant
- Betaine is a sugar-beet-derived humectant that cells use to hold water. In a formula it hydrates and takes the edge off cleansers and acids, which is why it often appears alongside them.
- 1,2-Hexanediol humectant
- 1,2-Hexanediol is a glycol used for two reasons: it holds water like glycerin, and it makes a formula harder for microbes to live in, so less traditional preservative is needed. Korean formulas use it heavily for that second reason.
- Polyglycerin-3 humectant
- Polyglycerin-3 is a short chain of glycerin units used as a gentler, less sticky humectant. It also helps oils and water stay blended.
- Tromethamine pH adjuster
- Tromethamine neutralises acidic thickeners such as carbomer so they gel, and holds a formula near skin-friendly pH. It is used at a fraction of a percent.
- Ethyl Ascorbyl Ether vitamin
- A vitamin C derivative with an ethyl group on the third position, the same molecule usually written 3-O-Ethyl Ascorbic Acid. The ether makes it far more stable in water than pure ascorbic acid.
- Hydroxyethyl Urea humectant
- Hydroxyethyl Urea is a humectant that holds a lot of water for its size and stays comfortable at high levels. It is used where a formula needs to feel deeply hydrating without oil.
- Betula Platyphylla Japonica Juice plant extract
- Betula Platyphylla Japonica Juice is Asian white birch sap, tapped in spring. It is over 98 percent water with trace minerals and sugars, and Korean formulas use it in place of plain water as a hydrating base.
- Ethylhexylglycerin preservative booster
- Ethylhexylglycerin softens skin and boosts a preservative system, which is why it is nearly always sitting beside phenoxyethanol or 1,2-hexanediol. It also cuts down the odour bacteria produce, so it turns up in deodorising products.
- Adenosine active
- Adenosine is a nucleoside that Korea's own cosmetic authority recognises as a wrinkle-care functional ingredient, which is why it appears on so many Korean lists at a low level. It is used for the look of fine lines and is stable and well tolerated.
5 more explained
- Disodium EDTA chelator
- EDTA is a chelator: it locks up trace metal ions from water and packaging that would otherwise turn a formula cloudy, off-colour or rancid. It does nothing to skin and appears at a fraction of a percent.
- Panthenol humectant
- Panthenol is pro-vitamin B5: skin converts it to pantothenic acid. It is a humectant that holds water and leaves skin feeling soft and less tight, and it is one of the ingredients formulators reach for when a formula also contains something harsh.
- Gardenia Florida Fruit Extract plant extract
- Gardenia Fruit Extract is the traditional East Asian yellow dye plant. In skincare it is used as an antioxidant extract, and it can tint a formula.
- Dextrin thickener
- Dextrin is a starch fragment used to thicken and to give a formula a light, powdery finish. It is also a common carrier for powdered extracts.
- Tocopherol antioxidant
- Tocopherol is vitamin E. It is an oil-soluble antioxidant that protects the oils in a formula from going rancid and works on skin as an emollient, and it is regularly paired with vitamin C because each keeps the other going for longer.
- Market
- Korean market, the version sold in Korea
- Made in
- Republic of Korea
- Volume
- 20ml
- Category
- Serum & Ampoule
- Actives
- Adenosine, Birch Sap, Panthenol, Urea, Vitamin C
- Ships from
- California or Korea
Orders ship from California or direct from Korea with tracked delivery to your door, and both routes carry the same Korean-market release. Shipping is free on orders of $100 or more. Returns are accepted for 30 days, by mail.
We split shipments free, so one out-of-stock item never holds up the rest of your order.
Where this unit came from
- 1Seoul
Bought as Korean-market stock - 2Barcode
Listed against the Korean barcode on its box - 3California or Korea
Ships to you from either, as the same Korean-market release
We stock the version of a formula that is sold in Korea, not the release a brand prepares for another market under the same name.
Every unit keeps its original barcode and batch code intact, so the unit in your hands can be checked against the brand’s own records.
Every order ships from California or direct from Korea, and returns run for 30 days.
Every claim on this page traces to the unit in the box, the barcode, the batch code and the price you can read for yourself.
How it works
The Hyper Vitamin C 23 Serum is a 20ml serum, used after toner and before moisturizer, morning and evening. The vitamin it is built around is Ethyl Ascorbyl Ether, named eighth on its own ingredient list. The same list carries Adenosine, Ascorbic Acid and Tocopherol, so the vitamin is not the only thing on it worth naming. How much of the Ethyl Ascorbyl Ether stays on the skin, and for how long, is decided by the serum format rather than by the list alone. Isntree sells this Ethyl Ascorbyl Ether serum in Korea, and this is that version.
How to use
- Use the Hyper Vitamin C 23 Serum after toner and before moisturizer, morning and evening.
- Three or four drops covers the whole face. Press it in with flat palms instead of rubbing it around.
- Toner first so the surface is damp, then this, then about a minute before your moisturizer goes over the top.
- Twice a day, every day. Do not stack it with a second serum of the same kind; two hydrating serums in one routine do the work of one.
Worth knowing
- Patch test this serum on a small area and wait a day before using it more widely, especially with Ethyl Ascorbyl Ether on the list.
- Introduce this serum on its own for the first week, so anything your skin does is traceable to the Ethyl Ascorbyl Ether rather than to three changes at once.
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Isntree Hyper Vitamin C 23 Serum 20ml
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Isntree, Korean-market original
The Original Korean Formula serum from Isntree, 20ml formulated with Ethyl Ascorbyl Ether and Adenosine, shipped from California or direct from Korea.
Verify your unit when it arrives
Verify your unit when it arrives
Korean-market stock with the original barcode and batch code intact, exactly as it left Korea.
On the unit itself
- The Korean-market barcode, unaltered from the retail package.
- The manufacturer’s batch code, exactly as the maker printed it.
정품Genuine article, Korean-market stock
What professionals say
What professionals say
What skin-care professionals say about the key actives in this formula, quoted from the medical sources linked beside each.
Using topical vitamin C can result in less cell damage and better-looking skin.
Melissa Piliang, MDDermatologist, Cleveland Clinic People with dry, flaky skin are more likely to see a benefit from using vitamin E because it enhances moisturization.
Amy Kassouf, MDDermatologist, Cleveland Clinic
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