IOPE Vitamin C Expert 40% Mask Concentrate 15g
Ascorbic Acid is the first entry on this list, in an anhydrous silicone and ester base with no water in the top ten, alongside Resveratrol and Nicotinamide Mononucleotide. 15 g, used once or twice a week.
No reviews yet- Ships from our California warehouse
- Duties prepaid
- Suited to
- Dehydrated skinSkin that has lost bounceDull, uneven tone
- Helps with
- Shoppers looking for Ascorbic Acid in a sheet maskRoutines that want Ascorbic Acid and Nicotinamide Mononucleotide in one stepFilling the sheet mask step with a Korean-market formulaAnyone who wants the Ascorbic Acid sheet mask sold on Korean shelves
In stock. Ships from our California warehouse, dispatched within 2 business days
You’re $100.00 away from free US shipping.
- Duties prepaid
- 30-day returns
- Free US shipping on orders of $100 or more
- Dispatched within 2 business days
Key benefits
- Ascorbic Acid, the antioxidant this sheet mask is built around
- Nicotinamide Mononucleotide on the same list, an active
- Thymol Trimethoxycinnamate and Resveratrol on the same list, antioxidants
- Glycine Max (Soybean) Polypeptide on the same list, a protein
- Hydrogenated Polyisobutene and Cetyl Ethylhexanoate further down the same list
- Triethylhexanoin and Polyglyceryl-3 further down the same list
Key actives
Ascorbic 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. The name on the box points at it, and it is named first on this sheet mask's own ingredient list.
Nicotinamide Mononucleotideactive
Nicotinamide Mononucleotide is a nucleotide built from vitamin B3 and a sugar phosphate. Korean formulas use it as a conditioning active, usually alongside niacinamide itself. It is named seventeenth on this sheet mask's list, alongside Ascorbic Acid.
Thymol Trimethoxycinnamateantioxidant
Thymol, the phenol from thyme, joined to a cinnamic acid ester. The ester form is oil soluble and stable, and it is used as an antioxidant. It is named fifteenth on this sheet mask's list, alongside Ascorbic Acid.
Resveratrolantioxidant
Resveratrol is an antioxidant from grape skin and Japanese knotweed. It is used for the look of dullness and is often paired with ferulic acid, which keeps it stable. The panel names it nineteenth on this sheet mask's list, beside Ascorbic Acid.
Glycine Max (Soybean) Polypeptideprotein
Soy protein cut into shorter polypeptide chains. The smaller chains dissolve in water and are used as a conditioning protein that leaves a smooth film. It is named twentieth on this sheet mask's list, alongside Ascorbic Acid.
How to use
- After cleansing, 1 to 2 times a week.
- Apply as directed, avoiding the eye area.
- Follow the product's own rinse-off or leave-on timing.
Where does this sheet mask go in my routine?
After toner, in place of your serum step, in the evening. Toner goes on before it, and the rest of the routine goes on after you take the sheet mask off. 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 Ascorbic Acid and not three changes at once.
Is this the Korean-market sheet mask or a US version?
The Korean-market one, Ascorbic Acid and all. We match this sheet mask to its Korean barcode before it reaches the shelf, which is the check that tells you which market release you are holding.
What else is on the list besides Ascorbic Acid?
Nicotinamide Mononucleotide, Thymol Trimethoxycinnamate and Resveratrol. The order they are printed in on this sheet mask's panel is the order on the box, so you can see where Ascorbic Acid sits relative to them. Further down the same panel: Glycine Max (Soybean) Polypeptide, Hydrogenated Polyisobutene and Cetyl Ethylhexanoate.
- Ships from
- California
Duties are prepaid. Nothing is owed at delivery. Returns are accepted for 30 days, by mail.
Orders ship from our California warehouse, dispatched within 2 business days, and arrive in 3 to 5 days. Shipping is free on orders of $100 or more.
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 - 2Customs
Duty paid by us before it enters the US - 3California
Ships domestically, no international leg
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.
Import duties are paid by us before the parcel reaches you, so nothing is owed at the door, 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.
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How it works
The Vitamin C Expert 40% Mask Concentrate is a 15g sheet mask, used after toner, in place of your serum step, in the evening. The antioxidant it is built around is Ascorbic Acid, named first on its own ingredient list. The same list carries Nicotinamide Mononucleotide, Thymol Trimethoxycinnamate and Resveratrol, so the antioxidant is not the only thing on it worth naming. How much of the Ascorbic Acid stays on the skin, and for how long, is decided by the sheet mask format rather than by the list alone. This is the Original Korean Formula, the sheet mask IOPE sells in Korea, Ascorbic Acid and all.
Worth knowing
- Patch test this sheet mask on a small area and wait a day before using it more widely, especially with Ascorbic Acid on the list.
- Introduce this sheet mask on its own for the first week, so anything your skin does is traceable to the Ascorbic Acid rather than to three changes at once.
Reviews
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Korean-market original
The Original Korean Formula sheet mask from IOPE, 15g formulated with Ascorbic Acid and Nicotinamide Mononucleotide, held in the United States and shipped domestically.
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.
Match the batch code on the box against the code printed on the bottle or tube itself; the two are stamped separately and should agree.
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 Using an antioxidant such as resveratrol helps boost your skin’s natural barriers so that your skin looks and feels smoother and healthier.
Michele Green, MDBoard-certified dermatologist, Byrdie
1 more professional perspective
Peptides can be anti-inflammatory, and chronic inflammation damages the tissue in your skin.
Wilma Bergfeld, MDDermatologist, Cleveland Clinic
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