Abstract: Process for depositing at least one thread or tape (3a, . . . 3d), generally a metal thread or tape, in particular made of magnetic material having a high permeability for an antitheft protection system, on a thin sheet (2) especially a plastic, paper or aluminum sheet, this sheet (2) being able to be joined to another sheet (1) with the thread or tape (3a, . . . 3d) sandwiched between them, the sheet (2) thus furnished with the thread or tape being intended subsequently to be wound up into a reel. The thread or tape (3a. . . 3d) is placed on the sheet (2) along a line (S) which is sinuous with respect to the longitudinal direction (D) of the sheet, the parameters (p, a) of the sinuosity being chosen so that, in a reel formed with the sheet, in one and the same plane passing through the axis of the reel, the thread or tape sections lying in two adjacent turns in the reel and in one and the same plane passing through the axis of the reel are offset transversely.