How do breathable films maintain high leakage resistance despite their porous structure?
It sounds like a paradox: a material filled with billions of holes that can still block water. However, the secret to MicroBreath™ technology lies in the precise management of physical dimensions and surface chemistry at the micrometer level.
The Scale Gap
Our pores are engineered to be 0.1 to 10 micrometers in diameter. To put this in perspective, a standard water droplet is roughly 100 times larger than these pores, making it physically impossible for liquid water to pass through under normal pressure.
Surface Tension
Kae Hwa membranes are naturally hydrophobic. The surface energy of the polymer prevents water from “wetting” the film. Instead of soaking in, water beads up and rolls off, utilizing surface tension as a secondary barrier against leakage.
Vapor vs. Liquid
Breathability happens at the molecular level. While liquid water is held back by the pore size, individual water vapor molecules (gas phase) are small enough to pass through the channels, ensuring the user stays dry.
Why It Matters for PPE & Medical Use
This high leakage resistance is what allows our fabrics to meet AAMI Level 4 and ASTM F1671 standards. Even under hydrostatic pressure, the combination of pore precision and material hydrophobicity ensures that viral pathogens and bodily fluids remain outside the barrier.