Method of making double-sided mosaic

Claim 1

THE PROCESS OF MAKING A DOUBLE SIDED STORAGE MOSAIC SCREEN, WHICH COMPRISES COATING AN ALUMINUM SHEET WITH PHOTO-ENGRAVING EMULSION, EXPOSING THE EMULSION THROUGH A SCREEN PROVIDED WITH OPENINGS OF GIVEN DIMENSION REMOVING THE UNEXPOSED EMULSION TO UNCOVER SAID METALLIC SHEET, PLATING COPPER ON UNCOVERED PORTIONS OF SAID SHEET, REMOVING EXPOSED EMULSION FROM SAID SHEET TO PROVIDE HOLES THROUGH SAID PLATED METAL, FILLING SAID HOLES W%ITH UNEXPOSED PHOTO-ENGRAVING EMULSION, EXPOSING SAID EMULSION THROUGH A TRANSPARENT MASK HAVING OPAQUE PORTIONS REGISTERING WITH SAID FILLED HOLES BUT OF SMALLER DIMENSIONS THAN SAID HOLES, WHEREBY AN EXPOSED RING OF SAID EMULSION IS FORMED, REMOVING THE UNEXPOSED EMULSION FROM SAID SURFACE, PLATING THE UNCOVERED PORTIONS OF SAID SHEET WITH SAID RINGS WITH COPPER, TO PROVIDE A COMPOSITE SCREEN OF COPPER AND EXPOSED EMULSION. AND DISSOLVING SAID ALUMINUM SHEET IN A POTASSIUM HYDROXIDE SOLUTION.