Non-electrolytic method for metallizing a substrate by the reduction of metallic salt(s) and the spraying of aerosol(s)

Non-electrolytic method for metallizing at least part of the surface of a substrate by spraying of at least one aqueous and/or organic aerosol containing at least one metal in cationic (oxidizing) form and at least one reducing agent, capable of converting the metallic cation to metal, the method essentially consisting of:

• -1- carrying out the metallization spraying according to a succession of at least two spraying phases, alternating with relaxation phases:
• (i) setting the duration Dp of the spraying phases between 10−2 and 5 s, for the same unit area, and the duration Dr of the relaxation phases between 10−2 and 10 s, for the same unit area, the durations Dp and Dr of these spraying and relaxation phases being identical to or different from each other, (ii) and adjusting the spraying flow rate(s), such that the Ox /Red electronic ratio is comprised between 0.01and 15, and thus allows the formation of a metallic film which is chemically adherent to the substrate;
• -2- interrupting the spraying as soon as the intended level of metal deposition is reached,
• wherein the improvement consists in:
• implementing at least one preliminary stage -ap- which consists in forming a fluid film consisting of water on an least part of the surface of the substrate;
• and, following the preliminary stage -ap-, commencing the spraying according to stage -1 - at the latest 60 s after the end of the preliminary stage -a p -.