What is the difference between silk and satin pillowcases?

Silk is a natural fiber produced by silkworms, while satin is a type of weave that can be made from any fiber — including polyester. A "satin pillowcase" sold at a low price point is almost always polyester satin, which looks shiny but does not offer the breathability, moisture-wicking, or hypoallergenic properties of real silk. Polyester satin can trap heat against your face and is derived from petroleum-based plastics.

Genuine silk satin pillowcases use the satin weave with real silk threads, giving you both the smooth surface and the natural benefits of the fiber itself. Look for momme weight (19–25 momme is ideal) and certifications like OEKO-TEX to verify quality.

ONDU only features pillowcases made from real silk or other verified natural materials so you never have to second-guess what you are sleeping on.