No.6 Deep Sleep Mask Serum 50ml
Numbuzin No.6 Deep Sleep Mask Serum 50ml carries four separate hyaluronic acid forms on its own ingredient panel, including Sodium Hyaluronate, Hydrolyzed Hyaluronic Acid, Hyaluronic Acid, Sodium Hyaluronate Crosspolymer.
No reviews yet50 ml
$65.00 per 100 ml
- Korean-market formula
- Ships from California or direct from Korea
- Korean barcode and batch code intact
- Suited to
- normalcombinationdryoily
- Helps with
- tone and texture supported by Glycerindaily hydration through the serum stepa Korean-market formula rather than a US reformulationa routine step matched to this format
In stock. Arrives in 3 to 7 business days
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How it works
The panel on this serum names four forms of hyaluronic acid rather than one: Sodium Hyaluronate, Hydrolyzed Hyaluronic Acid, Hyaluronic Acid, Sodium Hyaluronate Crosspolymer. Sodium Hyaluronate is the salt of hyaluronic acid, and it is what most products labelled hyaluronic actually contain. The salt dissolves more readily and the molecule is smaller, so it sits in the outer layer of skin rather than only on top of it. On this panel it sits alongside Glacial Water, Niacinamide and Chlorella Vulgaris Extract. Glacial Water is meltwater collected from glacier ice, used in place of ordinary water as a formula base. It is water with its own mineral profile rather than an active.
Key benefits
- Four forms of hyaluronic acid on one panel, not a single token inclusion
- Glacial Water on the same panel, the formula's plant extract
- Niacinamide on the same panel, the formula's active
- 50 ml to a unit
- Korean GS1 barcode matched against a Korea sourcing supplier's record for this item
Inside the formula
Inside the formula
Is this the same formula sold in Korea, or a US version?
This is the Original Korean Formula, carried through with its intact Korean-market batch coding. Numbuzin sells a separate reformulation on some US shelves, and this listing is not that version. The Korean-market batch coding and packaging travel with it, which is the detail worth checking against the box on arrival.
Where does this formula come from?
It comes from the Korean-market catalog rather than a US-shelf reformulation, and the packaging carries the same Korean-market batch coding a shopper would find on the box in Korea. That sourcing is checked on this row before the page is written, not assumed from the product name. It is the detail worth checking against the box on arrival.
Can I use this alongside other actives in my routine?
Yes. Glycerin is the lead active here, and it is formulated to sit alongside the rest of a routine rather than replace it. Introduce any new step on its own for the first week or two before adding it next to another strong active, so it is easy to tell which product is responsible for any change. Once it is settled into the routine, it layers the way any other serum in a Korean routine does.
What does Sodium Hyaluronate do in this formula?
Sodium Hyaluronate is the salt of hyaluronic acid, and it is what most products labelled hyaluronic actually contain. The salt dissolves more readily and the molecule is smaller, so it sits in the outer layer of skin rather than only on top of it. It is named on this product's own ingredient panel.
What does Niacinamide do in this formula?
Niacinamide supports an even-looking skin tone and works alongside the formula's humectants to keep the surface comfortable. It is one of the most studied actives in Korean formulation for tone evenness and is gentle enough for daily AM and PM use. It sits at its own position on this product's own ingredient list rather than being assumed from the product name.
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 (40): Glacial Water (63%), Butylene Glycol, Propanediol, Glycerin, Niacinamide, 1,2-Hexanediol, Purified Water, Chlorella Vulgaris Extract, Xylitylglucoside, Sodium Hyaluronate, Hydrolyzed Hyaluronic Acid, Xylitol, Melia Azadirachta Leaf Extract, Melia Azadirachta Flower Extract, Coccinia Indica Fruit Extract, Aloe Barbadensis Flower Extract, Solanum Melongena (Eggplant) Fruit Extract, Ocimum Sanctum Leaf Extract, Corallina Officinalis Extract, Curcuma Longa (Turmeric) Root Extract, Hyaluronic Acid, Glycereth-26, Panthenol, Pentylene Glycol, Glucose, Sodium PCA, Anhydroxylitol, Fructooligosaccharides, Fructose, Polyglyceryl-10 Laurate, Sodium Citrate, Dipotassium Glycyrrhizate, Sodium Hyaluronate Crosspolymer, Ethylhexylglycerin, Adenosine, Hydrolyzed Glycosaminoglycans, Citric Acid, Benzyl Glycol, Tocopherol, Xanthan Gum
Ingredient list read from incidecoder.com on 10 September 2026.
39 of 40 explained
- Glacial Water (63%) plant extract
- Glacial Water is meltwater collected from glacier ice, used in place of ordinary water as a formula base. It is water with its own mineral profile rather than an active.
- Butylene Glycol humectant
- Butylene Glycol is a small glycol that does two jobs at once: it holds water in the top layer of skin and it dissolves plant extracts and actives that plain water cannot. It also thins a formula, which is why watery Korean essences lean on it.
- 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.
- Glycerin humectant
- Glycerin is the most used humectant in skincare. It draws water into the outer layer of skin and holds it there, and it is one of the very few ingredients whose hydrating effect is settled science rather than marketing. Higher amounts feel tacky, which is why it is usually blended.
- Niacinamide active
- Niacinamide is vitamin B3, and it is the most studied active in Korean formulation. It is used at roughly 2 to 5 percent for the look of uneven tone and visible pores, and it is water soluble, stable and comfortable beside almost every other active, which is why it turns up in so many lists.
- 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.
- Purified 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.
- Chlorella Vulgaris Extract plant extract
- Chlorella Vulgaris is a freshwater green algae. Its extract carries proteins, chlorophyll and amino acids and is used as a conditioning ingredient.
- Xylitylglucoside humectant
- Xylitylglucoside is a sugar-derived humectant, the third member of the xylitol blend. Together the three hold water in the outer layer for longer than any of them does alone.
- Sodium Hyaluronate humectant
- Sodium Hyaluronate is the salt of hyaluronic acid, and it is what most products labelled hyaluronic actually contain. The salt dissolves more readily and the molecule is smaller, so it sits in the outer layer of skin rather than only on top of it.
- Hydrolyzed Hyaluronic Acid humectant
- Hydrolyzed Hyaluronic Acid is hyaluronic acid cut into much shorter fragments. The smaller the fragment, the further into the outer layer it can settle, which is why serums stack several sizes together instead of using one.
- Xylitol humectant
- Xylitol is a sugar alcohol humectant. It holds water in the outer layer of skin and is often paired with anhydroxylitol and xylitylglucoside as a hydration trio.
27 more explained
- Melia Azadirachta Leaf Extract plant extract
- Melia Azadirachta is neem. Its leaf and flower extracts are long-standing Ayurvedic ingredients, and Korean formulas use them in products aimed at the look of congested, blemish-prone skin.
- Coccinia Indica Fruit Extract plant extract
- Coccinia Indica is ivy gourd. Its fruit extract is used as a conditioning, hydrating plant extract in Korean formulas.
- Aloe Barbadensis Flower Extract plant extract
- Aloe Flower Extract comes from the flower rather than the leaf gel. It is used as a conditioning plant extract.
- Solanum Melongena (Eggplant) Fruit Extract plant extract
- Eggplant Fruit Extract carries nasunin, the antioxidant pigment in aubergine skin. It is used as an antioxidant plant extract.
- Ocimum Sanctum Leaf Extract plant extract
- Ocimum Sanctum is holy basil, or tulsi. Its leaf extract carries plant antioxidants and is used in formulas built for the look of stressed, reactive skin.
- Corallina Officinalis Extract plant extract
- Corallina Officinalis is coral seaweed, which holds calcium and magnesium in its structure. Its extract is used as a mineral-rich conditioning ingredient.
- Curcuma Longa (Turmeric) Root Extract plant extract
- Turmeric Root Extract carries curcuminoids, well studied plant antioxidants. It is used for the look of dullness and uneven tone, and it tints a formula faintly yellow.
- Hyaluronic Acid humectant
- Hyaluronic Acid is a sugar chain the body already makes, and one gram of it can hold several litres of water. In a formula it is a humectant that pulls water to the surface of skin and holds it in a film, which is what makes skin look plumper while it is there.
- Glycereth-26 humectant
- Glycereth-26 is a modified glycerin that hydrates with far less stickiness than glycerin itself. It is a common way to load water into a formula that has to stay light.
- 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.
- Pentylene Glycol humectant
- Pentylene Glycol hydrates and, like the other longer-chain glycols, makes a formula less hospitable to microbes so the preservative system can be lighter. It also improves how evenly a product spreads.
- Glucose humectant
- Glucose is a simple sugar used as a humectant and as food for the ferment ingredients in the same formula. It hydrates mildly and adds a soft slip.
- Sodium PCA humectant
- Sodium PCA is one of the substances skin makes for itself to hold water, part of what dermatology calls the natural moisturising factor. Added to a formula it is a strong humectant that suits skin that dehydrates quickly.
- Anhydroxylitol humectant
- Anhydroxylitol is a xylitol derivative used as a humectant. It is almost always part of the xylitol, anhydroxylitol and xylitylglucoside blend sold as a moisture-retention complex.
- Fructooligosaccharides humectant
- Fructooligosaccharides are short fructose chains used as humectants and as food for the skin's own resident microbes.
- Fructose humectant
- Fructose is a simple sugar used as a light humectant. It holds water in the outer layer and often arrives as part of a fruit or honey extract.
- Polyglyceryl-10 Laurate emulsifier
- Polyglyceryl-10 Laurate is a sugar-derived emulsifier and solubiliser, mild enough to be a standard choice in Korean essences. It dissolves small amounts of oil into water without any tightening feel.
- Sodium Citrate pH adjuster
- Sodium Citrate is the salt of citric acid, used as a buffer: it holds a formula at a steady pH rather than pushing it in one direction. It is also a mild chelator.
- Dipotassium Glycyrrhizate active
- Dipotassium Glycyrrhizate is a water-soluble salt derived from licorice root. It is the licorice fraction Korean formulas use for the look of redness, and it is far more stable in water than the whole extract.
- Sodium Hyaluronate Crosspolymer humectant
- Sodium Hyaluronate Crosspolymer is hyaluronic acid linked into a mesh. It holds water in a soft gel on the surface rather than sinking in, and it releases that water slowly through the day.
- 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.
- Hydrolyzed Glycosaminoglycans humectant
- Hydrolyzed Glycosaminoglycans are short fragments of the sugar chains that sit between cells in skin, hyaluronic acid among them. They act as humectants and give a cushioned feel.
- Citric Acid pH adjuster
- Citric Acid is used in tiny amounts to bring a formula to the pH its actives need, not as an exfoliant at that level. It is an AHA, so at much higher concentrations it can also exfoliate.
- Benzyl Glycol preservative booster
- Benzyl Glycol is a solvent that also makes a formula less hospitable to microbes, so it appears in preservative blends built without parabens.
- 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.
- Xanthan Gum thickener
- Xanthan Gum is a polysaccharide made by fermenting sugar. It thickens a watery formula into a gel and holds the whole thing in suspension so nothing separates. Too much of it and a serum turns stringy, which is why it appears in fractions of a percent.
- Market
- Korean market, the version sold in Korea
- EAN (barcode)
- 8809652580210
- Made in
- Republic of Korea
- Volume
- 50 ml
- Category
- Serum & Ampoule
- Actives
- Adenosine, Aloe Vera, Hyaluronic Acid, Licorice Root, Niacinamide, Panthenol, Sodium Hyaluronate
- 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. The barcode in the specification above is the Korean-market one and it is printed on the box you receive.
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 to use
- Finish the rest of your evening routine first, so this goes on over anything thinner.
- Press a thin even layer across the face and down the neck rather than rubbing it in.
- Leave it on overnight and cleanse as usual in the morning instead of adding more over the top.
- Do not use it as well as your night cream, since it stands in for that step rather than joining it.
Worth knowing
- Patch test on the inner arm first if trying a new brand's formula for the first time.
- Stop use and check the ingredient list against any known sensitivities before continuing.
Complete the routine
- This itemNumbuzin No.6 Deep Sleep Mask Serum 50ml$32.50

- Prep after cleansing, before the treatment stepnumbuzin No.3 Bifida Bakuchiol Exfoliating Toner Pads 190ml/70ea$40.00

- The treatment step of this routinenumbuzin No.3 Bifida Bakuchiol Zero Pore Serum 30ml$47.50

Total for 3 items$120.00
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numbuzin No.6 Deep Sleep Mask Serum 50ml
How it felt, how your skin took it, what you layer it with. Straight answers help the next person choose.
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Numbuzin, Korean-market original
The Korean-market serum built around Glycerin, from Numbuzin, sourced for the Korean market and reviewed before it ever reaches this page.
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 skin care, quoted from the medical sources linked beside each.
Your skin barrier is basically your outer layer of the skin.
Melissa Piliang, MDDermatologist, Cleveland Clinic Pretty much every step of a Korean skin care routine is going to have some component of hydration.
Alok Vij, MDDermatologist, Cleveland Clinic
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