English to French Tech/Engineering Patents (in a patent) Security documents and security devices comprising infrared-absorbent compositions

The inclusion of both the infrared-absorbent composition and the metal oxide nanoparticles in the same security device, according to the invention, may advantageously increase the overall security level of the security device, as the device may exhibit both visible optical effects and a covert infrared detectable feature. Alternatively or additionally, the visible optical effect of the security device may be provided on a window of a bank note, with the infrared-absorbent composition allowing improved detection of the bank note using certain infrared scanners. Furthermore, the transparent coating may protect the formations responsible for the visible optical effect from physical damage and fraudulent mechanical lifting.

By filling three-dimensionally structured formations 121, coating 113a also protects security device 104a from physical damage and prevents fraudulent mechanical lifting of its relief structure.