Process for the manufacture of a component comprising a stack of a functional layer on a composite film

A process of manufacturing a component that includes a stack of a functional layer on a composite film, the composite film includes a matrix made of thermoplastic polymer inside which are dispersed particles conferring physical properties on the composite film, the exodiameter of the particles being between 1 nm and 100 μm and the volume of the particles inside the composite film representing more than 1% of the volume of this composite film, said process comprising:

• a) depositing the composite film directly on a rigid substrate, a thickness of said rigid substrate is strictly greater than the thickness of the film, the composite film then exhibiting an external face turned an opposite way from the substrate, after depositing the composite film the temperature of the composite film being less than its glass transition temperature, then
• b) depositing the functional layer directly on the external face of the composite film, wherein, between steps a) and b), the process comprises:
• 1) heating the composite film in order for its temperature to exceed the glass transition temperature of its matrix, so as to soften it,
• 2) when the composite film is softened, flattening the external face of the composite film by a smooth face resting directly over the whole of this external face, said smooth face forming part of the front face of a flexible membrane, the whole of the rear face of which, located on the side opposite the front face, is pushed against the composite film by a fluid, then
• 3) cooling the composite film below the glass transition temperature in order to again harden the composite film, then
• 4) withdrawing the membrane in order to mechanically separate its front face from the external face of the composite film.