Method for electrochemically realizing a hydrophilic area on a hydrophobic substrate

A method for producing at least one hydrophilic area (1) on a substrate (2) which comprises a chemically inert material (3) and of which one surface to be treated (4) is coated with a hydrophobic film, said hydrophobic film comprising fluorinated organic groups, the method comprising performing an electrochemical reduction of the surface to be treated (4) wherein:

• the reduction is performed in an electrochemical cell (5) which is equipped with a reducing electrode (6) and a counterelectrode, and which contains an electrolytic solution (8) containing at least one solvent and a compound that is a precursor of a reducing agent, said compound being chosen so as to have a standard potential of less than −2.7 V relative to the saturated calomel electrode (SCE) and said compound corresponding to the general formula P(R1R2R3), in which at least one of the radicals R1, R2 and R3 represents a phenyl group bearing from 1 to 3 substituents, said compound being capable of forming an anion radical;
• the reducing electrode (6) is placed, relative to the surface (4) of the substrate, such that said surface (4) is facing the usable surface (7) of the electrode (6), said surface (7) of the electrode (6) being the image of the area to be reduced;
• and
• the reducing electrode (6) is subjected to the formation potential of the reducing agent.