Satin is a weave, not a fabric

This is the most important thing to understand. Satin is not a material. It is a way of weaving fabric that creates a smooth, shiny surface on one side.

Satin can be made from silk, polyester, nylon, or other materials. Almost all affordable satin pillowcases in the Philippines are made from polyester. The weave creates a smooth surface but the material underneath is still synthetic plastic fibre.

What real silk actually is

Real silk is a natural protein fibre produced by silkworms. Mulberry silk, which comes from silkworms fed on mulberry leaves, is the highest quality type. It has properties that polyester satin cannot copy, no matter how it is woven.

Why the difference matters

Temperature

Polyester does not breathe. It traps heat against your skin. On a humid Philippine night, a polyester satin pillowcase will warm up and stay warm. Real silk regulates temperature naturally. It stays cool and adjusts to your body temperature through the night.

Friction over time

New polyester satin feels smooth. After a few months of washing, the fibres start to pill and the surface roughens. Quality mulberry silk maintains its smooth surface much longer with proper care.

Moisture

Polyester does not manage moisture well. Sweat and oil sit on the surface instead of being regulated. Real silk has a natural protein structure similar to human skin and manages moisture in a way that polyester cannot.

How to tell if you are buying real silk

• The label should say 100% mulberry silk or 100% silk. If it says polyester, satin, or satin silk without specifying silk fibre content, it is polyester.
• Real silk lists a momme weight. Polyester satin does not use momme weight because it is not relevant for synthetic fabric.
• Price is a signal. A silk pillowcase at PHP 300 to PHP 600 is almost certainly polyester satin regardless of how it is labelled.
• OEKO-TEX certification means the fabric has been tested for harmful substances. More common with genuine silk brands.

Is polyester satin useless?

No. Polyester satin is better than rough cotton. It does reduce some friction. If you are on a very tight budget, it is a small step up.