US Patent 8636220 Printed planar RFID element wristbands and like personal identification devices

Each personal identification device includes a planar identification element with at least a core of flexible, porous and preferably microvoided polymer sheet material and a planar RFID assembly encoded with a unique electro/magnetic code permanently and integrally joined together with the core. The sheet material is sufficiently porous to collapse around the core so the sheet product remains planar yet flexible. A separate carrier can be provided or devices can be made in batches with scoring define one or more individual RFID devices removable from a remainder of a sheet product.