The Science Behind Silk and Hair Health
Hair damage during sleep is a well-documented phenomenon in trichology. The primary mechanism is mechanical friction between the hair shaft and the pillowcase surface. Cotton fibers, while comfortable, have a rough microscopic texture that catches and lifts the hair cuticle. Over weeks and months, this repeated friction leads to measurable increases in split ends, breakage, and moisture loss.
Silk operates differently at the fiber level. Mulberry silk fibers are composed of fibroin proteins arranged in a smooth, continuous filament. This structure creates a surface friction coefficient significantly lower than cotton, linen, or synthetic satin. Our lab testing, conducted on 22-momme charmeuse silk against 300-thread-count cotton, measured a 43% reduction in surface friction force.
Hair Type Considerations
Curly and textured hair types experience the most dramatic benefits from silk pillowcases. The tighter the curl pattern, the more vulnerable hair is to mechanical damage during sleep. Type 3 and Type 4 curl patterns are particularly susceptible to tangling and breakage on cotton surfaces. Silk allows curls to maintain their shape and definition without compression or friction-induced frizz.
Straight and fine hair also benefits, primarily through reduced static and preserved smoothness. Color-treated hair retains vibrancy longer because silk does not strip color-protecting oils the way absorbent cotton does.
Momme Weight and Hair Performance
Momme weight directly correlates with silk density and durability. Lower momme weights (16-19) are thinner and less durable, while higher weights (22-25) provide a denser, more protective surface. POSHEY uses 22-momme silk, which represents the optimal balance between surface smoothness, durability, and breathability for hair care applications. At this weight, the silk is substantial enough to maintain its friction-reducing properties through hundreds of wash cycles.
Silk vs. Satin for Hair
Satin is a weave pattern, not a material. Most affordable satin pillowcases are made from polyester, which does not share silk's moisture-regulating or hypoallergenic properties. While polyester satin is smoother than cotton, it generates static electricity and does not breathe. Genuine mulberry silk is a natural protein fiber with inherent temperature regulation and zero static buildup, making it categorically superior for hair health.
