A transponder label includes an antenna coil, a semiconductor chip, and a
single layer film, which acts both as a carrier film and as a shield
against the induction of counter magnetic fields in the metallic base
layer. The semiconductor chip acts both as a capacitor element of the
transponder resonant circuit and as a memory component. The film is a
flexible matrix including embedded ferrite particles, which give the film
soft magnetic characteristics. The permeability value of the film is
adapted to its thickness and the material of the base layer, the value
being higher for a reduced thickness. The resonant frequency of the
transponder resonant circuit formed from the antenna coil and
semiconductor chip lies within a narrow target frequency range, once the
label has adhered.