In the electrolytic refining trials showed in this paper, a prominence was the use of permanent stainless steel cathodes. The active surface of these cathode blanks is the same as that of the conventional tin starting sheets even slightly larger than the anode surface. However he total length and width are larger in order to provide room for the border insulating removable bands. This is necessary to allow the striping of the plated tin layer. The use of the stainless steel blanks brings some interesting features mentioned above. Besides those, there are additional features such as (1) the sheet small thickness that reduces the electric gradient between the faces; (2) the metallographic structure of refined and regular grains leads to a more homogeneous distribution of the electric current; (3) the typical surface hardness prevents bending and scratching during stripping and thus impedes the current concentration in points and avoids adherences; (4) the stainless characteristic of the material and the chromium oxide coating, imputes a capacity to resist the acid environment and prevents alloying that makes possible the stripping.
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