Remanent magnetic field measurements were performed on various tinplate samples in two magnetic states. In the first one, the tinplate had been magnetised through a 1000 gauss permanent magnet, while, in the second state, it was, moreover, submitted to CORONA discharge. From these measurements, a magnetic parameter was described, which depends on the tinplate passivation film nature. An interpretation of this parameter is proposed. Its variation with the ageing of a fresh CDC passivated tinplate is accompanied by parallel variations of the lacquer adhesion on tinplate. This phenomenon is so general that we can specify conditions where the lacquer adhesion on CDC passivated tinplate is appreciably increased.
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