Materials

7 fabrics and fills, described by what they do

Every page here answers the same five things in the same order: what it is, how it is made, how it behaves wet, how it behaves hot, and what fifty washes do to it. Nothing is graded, because a fabric is not better or worse in the abstract, only better or worse at the job you are giving it.

Cotton Percale

Percale is cotton in a plain weave: one thread over, one thread under, evenly, all the way across. That is the entire definition. It is not a quality tier and it is not a brand, and any cotton fabric woven that way can be sold under the word. What the structure gives you is a matte surface with no sheen and a hand that people describe as crisp, which is really just a fabric with nothing floating loose on the face of it.

Wet: Cotton absorbs a lot of water relative to its weight and gives it back slowly.
After fifty washes: Percale softens and it does so unevenly, starting where the fabric flexes most.

Cotton Sateen

Sateen is cotton woven so that several threads float across the surface before being tied down, instead of interlacing every single time. Those floats catch light, which is where the faint sheen comes from, and they present more unbroken yarn to your skin, which is where the heavier and smoother hand comes from. It is the same fiber as percale doing a different job because it was threaded differently.

Wet: It behaves like the cotton it is: absorbent, slow to dry, heavy while damp.
After fifty washes: The sheen dulls.

Microfiber

Microfiber is polyester, extruded as filaments fine enough that the fabric behaves differently from ordinary polyester cloth. The word describes the fineness of the fiber, not the fiber itself, so a microfiber sheet is a polyester sheet with a specific manufacturing spec. Listings use the texture word far more often than they use the fiber word, and both are accurate.

Wet: Polyester absorbs very little water into the fiber itself; water sits between the filaments instead.
After fifty washes: Microfiber pills, and it pills more visibly than cotton because the pills are polyester and they hold color.

Rayon and Viscose from Bamboo

This is rayon. Bamboo is the plant the cellulose was taken from, and the fabric that results is a regenerated cellulose fiber, not bamboo in any structural sense. The FTC has been explicit that textiles made through the viscose process have to be labeled as rayon or as viscose, with bamboo mentioned only as the source of the raw material. Listings that say bamboo alone are not describing what is in the box.

Wet: Rayon takes on a lot of water and loses strength while it is holding it.
After fifty washes: This is where rayon shows its weakness.

Satin Weave

Satin is a weave in which long floats run across the surface with very few tie-down points, producing the highest shine of any common construction. It says nothing about what the threads are made of. Silk satin, polyester satin and nylon satin are all satin. In bedding the fabric is most often a polyester filament, because filament is what holds that particular shine, but that is a general fact about the category and not a statement about any specific set. The one satin listing in this catalog names the weave and does not name the fiber, so this site records the fiber as unstated.

Wet: If the fiber is polyester, water sits on the surface and the fabric dries quickly, and the shine survives washing well.
After fifty washes: The floats are the whole problem.

Memory Foam

Memory foam is polyurethane foam modified to be viscoelastic, meaning it deforms slowly under load and returns slowly when the load comes off. That delay is the entire product. It shows up on this site in two very different forms: solid slabs cut for toppers, and cross-cut or shredded pieces packed into pillow shells where the fill can be added or taken out.

Wet: Badly.
After fifty washes: The question does not apply to the foam, because the foam has not been washed fifty times and must not be.

Down Alternative Fill

Down alternative is polyester fiberfill. The name is a comparison to a different product rather than a description of this one, and it appears on both pillows and comforters throughout this catalog. Some of it is loose staple fiber, some is spun into small clusters meant to behave a little more like down does, and listings almost never say which.

Wet: The fiber itself takes on almost no water, but a pillow or comforter full of it holds an enormous amount of water between the fibers, and that weight is what does the damage.
After fifty washes: Fiberfill clumps.

What the marks on these listings cover, and what they do not

Certification marks are the most technical looking thing on a bedding listing, which is exactly why they get read as proof of quality. None of them is that. Each one below is a specific program with a specific scope, and the second column is the part that gets left out of the sales copy.

OEKO-TEX Standard 100OEKO-TEX: Standard 100: What it coversA tested article has been checked against a list of regulated and restricted substances, at limits set for how close the article sits to skin. It is a chemical screening of the finished item.; What it does notIt says nothing about how long the fabric lasts, how it feels, whether the fiber content on the label is accurate, or whether the item is suitable for any particular person.
OEKO-TEX Made in GreenOEKO-TEX: Made in Green: What it coversAdds a traceability and facility-conditions component on top of the substance testing, and gives the article an ID you can look up.; What it does notIt is still not a performance standard, and it does not grade quality, durability or comfort.
GOTSUSDA Agricultural Marketing Service: Organic Labeling: What it coversThe Global Organic Textile Standard is a privately administered standard covering organic fiber content along with processing, chemical inputs and social criteria through the supply chain. It is a supply-chain standard, and it is run by a non-governmental body rather than by a US agency.; What it does notIt does not measure how the finished fabric performs, and organic content is a statement about farming rather than about durability or feel. In the United States, what the word organic can legally claim is governed by the USDA rules linked here, and a private textile standard is a separate thing from that.
CertiPUR-USCertiPUR-US: what the program covers: What it coversA program for flexible polyurethane foam covering what the foam is made without, including certain flame retardants, heavy metals and phthalates, plus a limit on volatile organic compound emissions.; What it does notIt is not a comfort rating, not a durability rating, and not a statement that a foam product is appropriate for any person or any use. It applies to the foam, not to the cover or the finished item.
GREENGUARD GoldUL Solutions: GREENGUARD Certification: What it coversA chemical emissions certification: the product has been tested for what it releases into indoor air against the program limits, with Gold being the stricter tier.; What it does notEmissions testing is not a health outcome, not a quality grade, and not a claim about anyone with a particular sensitivity.
Good Housekeeping SealGood Housekeeping Institute: what the Seal is: What it coversA limited warranty offered by the magazine on products it has evaluated, tied to advertising in its pages. Its own explanation of what it is and how a product gets it is linked here.; What it does notIt is not a government certification, not an independent laboratory standard, and not evidence that one product outlasts another.
HypoallergenicFDA: Hypoallergenic Cosmetics (the term has no federal definition): What it coversNothing enforceable. It is not a certification at all, and it appears on this site only when quoting what a listing says.; What it does notThere is no federal definition governing the word on bedding. FDA has stated for cosmetics that there are no standards or definitions behind it, and no agency defines it for textiles either. Treat it as seller language everywhere it appears.

When a listing never names the fiber

Of the sheet sets in this catalog, 6 do not give a generic fiber name on their listing. 3 of those say nothing at all about what the fabric is, and those 3 appear on no material page at all. The rest use a word that names a weave or a filament fineness rather than a fiber; those are listed on the page for that weave or fineness, which says in its own text that the fiber is unstated. What none of them gets is a fiber this site picked for them.

That is deliberate. Guessing a composition from a texture word would make this site look more complete and would make it wrong. The gap belongs to the seller, and leaving it visible is the only honest way to show it. The sets in question are grouped under a heading that says so on Sheet & Pillowcase Sets.