A plain-English guide to silk pillowcase weight, and why 22-momme is the weight worth putting your face on.
If you have shopped for a silk pillowcase lately, you have run into this number: momme. One listing claims 16, another 19, the better ones say 22 or 25. The number is rarely explained, so it reads like a spec sheet you are expected to take on faith.
Here is the honest version, in five minutes.
What is momme, actually?
Momme (pronounced "mommy") is a Japanese unit of weight, and in silk it describes how heavy the fabric is: specifically, the weight in pounds of a piece 45 inches wide and 100 yards long. You do not need to remember that. What matters is what it tells you.
Higher momme means denser, heavier, more durable silk. More silk in the same area. More thread to wear through before the fabric gives up. That is the whole concept. No marketing trick, just weight.
The weights you will actually see
16-momme
The entry-level weight. It feels silky but thin, closer to a slip dress than something built for bedding. It wears out faster, and it pills and snags more easily, because there is simply less fibre taking the load. Common in low-priced "silky" pillowcases and cheap sleep masks.
19-momme
The weight a lot of pillowcases settle on, because it is lighter and cheaper to weave. We do not sell it.
It is noticeably lighter in the hand than 22-momme, the weave is more translucent, and it thins and pills sooner under nightly use. It is a perfectly real silk. It is just doing less work.
22-momme
The sweet spot for a pillowcase. Dense enough to have real weight and drape, cool and smooth like any genuine silk, and durable through hundreds of washes. The thread count per square inch is high enough that the fabric is opaque and holds light properly instead of looking flat.
This is the weight that takes nightly friction for years and still breathes. It is where the durability curve and the comfort curve cross.
25-momme and above
Above 22, returns start to diminish. 25 and 30-momme silks exist, but they behave like a heavy charmeuse and are generally made for garments, robes and evening wear, rather than bedding. They are warmer to sleep on, which is the opposite of what most people want silk for. For a pillowcase, 22 is the ceiling most people will actually notice.
The short version of all that
Momme measures the weight of the fabric. 19-momme is lighter and cheaper to weave. 22-momme is dense enough to take nightly friction for years and still breathe. 25-momme and above is heavier and sleeps warmer.
What momme does not tell you
Momme is the headline number, but it is not the whole story. Three other things matter, and a pillowcase can be 22-momme and still be poor if it gets them wrong:
- Grade. Mulberry silk is graded on the length and uniformity of its fibres, running from 6A at the top down through 5A, 4A and lower. Longer, more uniform fibres make a smoother surface that resists pilling.
- Staple length. Long-staple silk is stronger, smoother, and resists pilling. Short-staple is what cheaper fabric uses, and it is what gives silk its undeserved reputation for falling apart.
- Weave and finish. A charmeuse weave is what makes silk feel slippery and cool. A 22-momme silk with a poor finish can still feel papery in the hand.
Translation: do not buy silk on momme alone. Ask about grade, staple and weave too. If a seller will not tell you, that is usually your answer.
The short version
Momme is weight, weight is density, and density is durability. More is better up to about 22, after which the gains are marginal and the fabric starts sleeping warm. Below 22 you are simply getting less silk against your face.
The Aveloor Silk Pillowcase is 22-momme Grade 6A mulberry silk, in 17 colours.
Written by Samuel, Founder.
