Forty-three thousand eight hundred and ninety-eight parts per million. Korean brands love a ppm figure, and this one is printed on the sachet as if it were a dose of medicine. Converted, it is about 4.4 percent hydrolyzed collagen, which is a lot for a sheet-mask essence and explains why collagen sits second on the ingredient list, directly after water. What it cannot do is the thing the number invites you to imagine. Collagen peptides applied to the skin do not travel to the dermis and do not become collagen; they sit on and just inside the surface as a film that holds water beautifully. Read the number as a hydration claim and the mask makes complete sense.
Moistfull Collagen is Etude's oldest skincare franchise, a 'super collagen water' story that has carried creams, toners and eye creams since the Etude House years. The Deep Sheet Mask is the richer sibling of the original Moistfull mask, and the difference is in the emulsion. Instead of a watery humectant serum, the sheet is soaked in a milky essence built on cetyl ethylhexanoate and caprylic/capric triglyceride, with ceramide NP and cholesterol carried by hydrogenated lecithin and a set of polyglyceryl emulsifiers. Hydrolyzed lupine protein, the white-lupin seed peptide Etude calls its super plant, adds a second film-former. Then the humectants: glycerin, glycereth-26, trehalose, panthenol and sodium hyaluronate. Then, at the tail, green tea, ginger, licorice and coptis extracts, arginine, and a fragrance.
That is a barrier-minded formula at a price usually reserved for water and glycerin, and it shows in use. The cellulose sheet is soft, faintly stretchy and fits an ordinary face with a fold at the nose and a tug at the jaw; it goes on cool and stays saturated for the full twenty minutes. The sheet is the trick, of course. A sheet mask works by acting as an occlusive lid, stopping evaporation while the humectants pull water into the stratum corneum, and a 2024 study of mask timing found hydration rising and water loss falling in the first twenty-odd minutes and reversing after that as the sheet dries. This essence is thick enough not to drip and generous enough to leave a puddle when the sheet comes off.
The result, patted in, is the classic Korean sheet-mask afterglow: skin visibly plumper, cooler, more even in tone, with a dewy finish that lasts the evening and a softness that survives into the morning. On dry and dehydrated skin in winter, when a plain humectant mask can feel like it evaporates before bed, the ceramide emulsion gives this one a lasting, cushioned comfort. On oily skin it is richer than necessary and the film can read as tacky if too much essence is left on; a light pat and a tissue solve that. The soothing extracts are present in small amounts, but a face that is flushed after a hot shower does come out calmer.
It is worth being precise about what the ceramides are doing here, because 'barrier repair' is the phrase attached to every product that contains one. In a leave-on cream at meaningful concentration, a ceramide-cholesterol-fatty-acid mixture can measurably improve barrier function over weeks. In a sheet-mask essence worn for twenty minutes, the same ingredients at unknown and certainly modest levels are doing something humbler: leaving a thin lipid film that slows evaporation after the sheet comes off, so the water the humectants pulled in stays put for longer. That is the difference between this mask and a watery collagen sheet, and it is a real difference in how the skin feels at midnight, but it is comfort, not reconstruction.
The limitations are the ones the label makes plain. Fragrance is the last ingredient and a sweet, powdery one, which rules the mask out for the fragrance-averse and makes it a less obvious choice for reactive skin than its gentle formula would otherwise suggest. The collagen is animal-derived, so the mask is not vegan even though its sheet is plant cellulose and marketed as such. Fungal-acne-prone skin may react to the fatty esters and polyglyceryl emulsifiers. And the regeneration language, protein regeneration, collagen recharge, is the kind of copy that makes a scientist wince; the essence hydrates, and hydration is enough.
A note on the number, because it has moved. Newer official listings quote a higher collagen figure than the one on most retailer pages, which suggests a recent reformulation or a change in how the brand counts; the ingredient order has not visibly changed, and the mask's behaviour in use has not either. It remains what it has been for years, a reliably plumping, unusually well-constructed budget mask with an audience of thousands of repeat buyers who have stopped reading the ppm and started reading their skin. For a first sheet mask, or for a winter box to keep in the fridge, it is hard to name a more sensible place to start.
