Card provided with a microprocessor and/or at least one electronic memory

An electronic card having electronic circuitry comprising at least one of a microprocessor and at least one electronic memory and having contacts which are accessible from the outside of the card, the card being made of at least three layers of compatible plastic materials which are of different compositions and different characteristics forming, after hot rolling, a monolithic assembly of a core and two protecting layers of lesser thickness than the core and covering two opposite faces of said core, a film on at least one of the faces of which conductors are secured, at least one end of certain of these conductors being electrically connected to contacts also secured to said film, said film comprising at least one aperture into which extends the other end of at least some of said conductors, these latter ends of said conductors being welded to the terminals of at least one solid state circuit located in the said aperture of the film;

• the film and the electronic circuit carried by it being positioned between the core and one of the protecting layers, the core filling all the free spaces located around the solid state circuit and the conductors in the said aperture of the film, one of the protecting layers having a slot giving access to the contacts carried by the film.