Abstract: A method of fabricating very fine metal screens for use in a transparent or translucent panel through which visible light is transmittable but which acts as a barrier against transmissions of pulsed electromagnetic radiation which may be harmful to humans or disruptive to electronic gear. The screens are fabricated by printing a pattern photographically upon a first surface of a metal foil covered on both sides by a positive, photo sensitive etchant mask and removing exposed areas of the mask with a developer. The masked foil is then chemically blanked by application of an etchant to the first side only of the foil. The specimen is rotated 90 degrees on a frequent basis to prevent selective etching, especially in areas adjacent the periphery of the screen.

Abstract: A composition and process for the removal of phenolic resin composites from aluminum and its alloys which results in a minimum of corrosion to said metals. The process uses a solvent solution of nitric acid, a hexavalent chromium and incidental water in the proportions of about 0.01-0.12 moles of hexavalent chromium and 1-1.7 moles of H.sub.2 O per mole HNO.sub.3.