Process for producing punching steel sheets, in particular paper-punching steel sheets

摘要

In a process for producing punching steel sheets, in particular paper-punching steel sheets, the starting sheet is provided, symmetrically to the cutting edge contour, with an etch resist mask corresponding to the form thereof and then subjected to deep etching. Subsequently, the etch resist mask is removed, and finally fine etching is carried out. Particularly good sharpness of the cutting edge is then obtained if the starting sheet is initially provided with two etch resist masks, arranged one above the other symmetrically relative to the cutting edge contour, of different material, of which the upper mask covers the lower mask, the material of the starting sheet is removed during the deep etching to the extent of 85 to 95% of the depth of the cutting edge and, after the deep etching, the upper etch resist mask is removed and fine etching is carried out up to complete etching underneath the lower etch resist mask.