| 摘要 |
In order to improve the solderability of printed-circuit boards, their conductor tracks are normally coated with tin solder which was briefly in the liquid state during production. In the case of such tinned printed-circuit boards, after a relatively long storage time, difficulties result with respect to the solderability since, as a result of the surface tension of the liquid tin, this is sucked off from the edges of the holes and is drawn into said holes. A sequence of method steps which are known per se is therefore proposed according to the invention, which method steps contain a second masking process but require no remelting or hot tinning for said purpose. <IMAGE>
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