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Sei Pillowcase Single

Sei Pillowcase Single

100% Cotton | 600 Thread Count | Sateen Weave | Garment-Dyed

Regular price $50
Regular price $125 Sale price $50
Sale Sold out

MATTEOX Exclusive, 40% discount auto-applies at checkout.

Color Off White
Size Size guide
Quantity

Description

Sei pillowcases are finished with a half inch hem with a double stitch detail. Darker colors feature a contrasting white top stitch detail.

Pillowcase vs. Sham

Pillowcases and Shams are both used to protect pillow inserts, but there are a wide variety of constructions. Typically, pillowcases loosely encase the pillow and are open on the side, whereas shams are more fitted and employ some method of closure to keep the pillow in place.

We recommend using a Queen pillowcase for a Standard pillow insert as we do not offer a Standard pillowcase. The pillowcase will hang a bit longer over the edge of the insert. It can be tucked in to create an envelope closure or taken to a seamstress for a simple alteration.

  • 100% cotton
  • Sateen weave
  • 600 thread count
  • Garment-washed

Fabric

Sei is our highest thread count fabric at 600 TC. We are not myopically focused on thread count at MATTEO. Thread count is one among many measurements of quality in the world of bed linens. The most simple definition of thread count is to take a pair of scissors and cut out a square inch of fabric and count each individual yarn (or thread). This is the thread count and, as such, thread count is simply a definition of the density of the weave. It does not take into consideration the softness of the raw cotton used or the size and smoothness of the yarn, nor does it measure the balance of the weave. Focusing only only thread count is similar to deciding which beer to drink by only measuring its alcohol content.

We have not yet gone above 600 thread count at MATTEO because higher counts typically produce a stiff and dense fabric that does not move or breathe. All sateens (or satin) fabrics have a face which is softer and a backside which is rougher. This is what creates the "silky" feel that customers love so much. And our customers love Sei because it is one of the purest, softest, and silkiest fabrics on the market.

Care Details

Wash

Wash should be separated into light & dark colors. Do not overload machine as this will damage long cotton fibers. We recommend a lukewarm wash cycle with a gentle detergent & a cool rinse.

Bleach may be used on white cotton bed linens only. Avoid using products that contain whitening agents such as chlorine bleach, alpha hydroxy acids and benzoyl peroxide on garment-dyed items. The reactive dyes used for garment-dyeing are not resistant to these whitening agents.

The largest challenge with garment-dyeing is the truth that it is an art, and not a science. We must allow for a shade variation of +/- 10% from dye-lot to dye-lot.

Learn more about Garment-Dyeing.

Drying

Tumble dry with low heat.Remove bed linens promptly from the machine to reduce wrinkling. For best results, line dry.

Ironing

We at MATTEO tend to prefer a lived-in look, as such, you don't find us ironing our sheets too frequently. If you prefer a crisp looking bed, our cotton bed linens should be pressed while slightly damp using the Lightweight Cotton or Medium setting.

Size

inches cm
King 20 x 39 51 x 99
Queen 20 x 33 51 x 84

Important Notice

All products purchased from the MATTEOX clearance page are samples that might exhibit visible flaws, including, but not limited to, off-color shades, incorrect threads, and faded edges. Products purchased in the same color might be different tones owing to differences from their respective dye lots. Products purchased at 50% off are eligible for a full refund. Products purchased at 60% off are only eligible for exchanges or store credit. Products purchased at 80% off or below are FINAL SALE.

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Frequently asked questions

What fabric is the Sei Pillowcase made from, and what is the thread count?

The Sei Pillowcase is 100% cotton in a sateen weave, garment-washed, at 600 thread count. Sei is MATTEO's highest thread count fabric, and the 600 TC ceiling is intentional: counts above 600 typically produce a stiff, dense fabric that resists airflow. The 120/2 Ne yarn used in both warp and weft gives Sei its silky face and balanced hand.

Is a higher thread count always better in a cotton pillowcase?

Thread count measures weave density, not overall quality. It does not account for the softness of the raw cotton, the diameter and smoothness of the yarn, or the balance of the weave. At MATTEO, we stopped at 600 TC because going higher tends to produce a stiffer, less breathable fabric. Fiber quality, yarn construction, and finishing process all contribute more to how a pillowcase actually feels than the thread count number alone.

What sizes does the Sei Pillowcase come in, and will it fit a Standard pillow?

The Sei Pillowcase is available in Queen (20 x 33 inches / 51 x 84 cm) and King (20 x 39 inches / 51 x 99 cm). MATTEO does not offer a Standard size; we recommend using the Queen pillowcase on a Standard insert. The extra length can be tucked in to create an envelope closure, or a seamstress can take it in with a simple alteration.

What is the difference between a pillowcase and a sham?

Pillowcases loosely encase the pillow and are open on one side, which makes them easy to slip on and off. Shams are more fitted and use a closure, such as an envelope flap or zipper, to keep the pillow in place. The Sei Pillowcase is an open-end style, finished with a half-inch hem and a double stitch detail.

How do I wash and care for the Sei Pillowcase to protect the garment-dyed colors?

Wash lights and darks separately in a lukewarm cycle with a gentle detergent and a cool rinse; do not overload the machine, as excess friction can damage the long cotton fibers. Bleach may be used on white cotton only. On garment-dyed colors, avoid products containing chlorine bleach, alpha hydroxy acids, or benzoyl peroxide, as reactive dyes are not resistant to these whitening agents. Tumble dry on low and remove promptly, or line dry for best results. Learn more about MATTEO's garment-dyeing process.

Is the Sei Pillowcase suitable for sensitive skin?

The Sei Pillowcase is made from 100% cotton and dyed using non-toxic reactive dyes, with no synthetic fiber blended into the fabric. The garment-washing process softens the cotton before it reaches you, so the face of the fabric is smooth and gentle from the first night. If you have specific chemical sensitivities, the care instructions recommend avoiding bleach and whitening agents, which can degrade the dye and the fiber over time.

Does the Sei Pillowcase work well as a hotel-quality pillowcase?

The Sei Pillowcase is 100% long-staple cotton sateen at 600 thread count, garment-washed and finished with a double stitch hem. That combination of fiber quality, weave density, and pre-washed finish produces the smooth, silky hand associated with high-end hotel bedding. The white and off-white colorways in particular are well-suited to a clean, hotel-style bed presentation.

Can I buy a single Sei Pillowcase, or do I have to purchase a pair?

The Sei Pillowcase is sold individually, so you can buy exactly the quantity you need. It is available in Queen and King sizes across fifteen colors, including White, Off White, Greige, Mica, Iris, Alpine, and several deeper tones. Darker colors include a contrasting white top stitch detail that reads as a subtle design finish rather than a purely functional seam.