Vacuum Metallization of Textiles
topic
Vacuum metallization deposits aluminum or other metals onto textile substrates at 10⁻⁴ to 10⁻⁵ mbar chamber pressure by resistive or electron-beam evaporation, achieving coating thickness of 50–200 nm in 3–8 seconds at web speeds of 100–400 m/min. Infrared reflectivity exceeds 92% for 80 nm aluminum layers. Adhesion to polyester requires corona pretreatment (40–50 mJ/m² surface energy) or thin primer coat. Electrical sheet resistance of 0.5–5 Ω/sq enables EMI shielding of 30–50 dB (MIL-STD-461). Used in emergency mylar blankets, radiant barriers for roofing membranes, and capacitor dielectric films. Metallization cost is $0.10–0.30/m² at high production volumes.
Role
Most cost-effective method for applying continuous metallic reflective layers to flexible textile substrates at industrial scale, enabling mass production of emergency thermal blankets and radiant barrier construction membranes.