The present study proposes a complete characterisation of the liquid gold silver layer on glass, from the application of the initial product, to the final metallic film obtained. The decomposition of organometallic compounds, during the heating, has been followed using different spectroscopic methods (infrared, nuclear magnetic resonance, mass spectrometry, etc.) which were coupled with thermal analyses and microscope observations (SEM, TEM, etc.). In the present paper the steps of the formation of the film will be briefly described, and a special attention is given to the study of the adhesion mechanisms which operates at the interface between the gold film and the glass substrate. Specific adhesion tests have been performed by aging the system in controlled solutions and observing the loss of adhesion after a given immersion duration. In depth concentration profiles obtained by secondary ion mass spectrometry and Rutherford back-scattering spectrometry reveal, during the process, a migration of the precious metals into the substrate. That migration ensures a good adhesion for the film. That 'diffusion' of gold into the glass substrate does not follow the classical diffusion laws and does not seem to be the only explanation for the occurrence of a good adhesion between to two partners. The results also suggest an essential role played by flux agents as vanadium, whose interaction with the alkaline modifiers of the bulk glass constitutes a critical factor for the durability of decorations.
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