Abstract:
The invention relates to a flat insert intended for being inserted in a security document, which includes a fibrous substrate (2) formed as a single layer having a cavity (5) and an electronic device (3) having contactless communication, housed in said cavity. Said cavity is in communication with a single surface of the fibrous substrate (2) and includes, in the cross-section thereof, a peripheral shoulder (13) for housing said electronic device in said cavity without generating a thickened portion of the insert, said fibrous substrate (2) including synthetic fibres.