The present invention relates to a method and a device for rapidly stress relieving laminated RFID cards sheets (1) or individually cut cards (2) so that the effect of card wrap, bending and distortion is reduced. A freezer tunnel (5) is located down-stream of a laminator machine. The freezer tunnel (5) uses nozzles (8) to supply a cryogenic liquid in vaporized form. Laminated RFID card sheets (1) are transported through the freezer tunnel (5), where they are exposed to an ambient temperature between −40° C. to −100° C. during two minutes or less.