Wikipedia
Kydex
Kydex is a line of thermoplastic acrylic- polyvinyl chloride materials manufactured by Sekisui SPI. It has a wide variety of applications, including for aircraft bulkhead (partition)s, firearm holsters, sheaths, and for knives.
Similar acrylic polyvinyl chloride material ( IPK Acrylic-polyvinyl chloride) is manufactured by Emco Plastics and Interstate Plastics, which carries nearly identical properties with an added layer for screen printing.