US 4,362,595 AGranted

Screen fabrication by hand chemical blanking

AssigneeThe Boeing Company

InventorJack E. Skog

Life of this patent

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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. The protective mask and the mask on the second side of the foil are then exposed to light and removed from the screen leaving a screen presenting minimum optical distortion and visual blocking therethrough and possessing unimpeded electrical conductivity in all directions.

Claims11

Dependent claims

A method of preparing a screen from a thin metal foil having thin wire strands with uninterrupted electrical conductivity in all directions comprising the steps of:

(a) applying photosensitive coatings to first and second sides of said foil to form an adherent, etchant resistant coating thereon;
(b) exposing a pattern in said coating on said first side to light and removing solubilized exposed areas of said coating whereby a grid pattern of an unexposed, protective, etchant resistant coating corresponding to the desired screen pattern remains on said first side of said foil with areas of said foil exposed;
(c) applying by hand under visual observation a chemical etchant to said exposed areas of said foil on said first side when said foil is in an approximately vertical position;
(d) observing the action of said chemical etchant to identify areas of uneven etching;
(e) rinsing selected areas of said first side with a neutralizing fluid when necessary to prevent further etching;
(f) rotating said foil into a new orientation while maintaining the foil in the approximately vertical position;
(g) repeating steps (c), (d), (e) and (f) until said screen has been properly etched from said foil by removing exposed areas of said foil;
(h) rinsing said chemical etchant from said grid;
(i) removing all remaining coating on said first and said second sides of said foil;
whereby a screen grid remains having unimpeded conductivity in all directions.

7 more elements

Dependencies are inferred from the claim text.

Facts

Application: 06/150,735Filed 19 May 1980
Granted: 7 Dec 1982
Term ends: Not estimatedThe source records don’t support an estimate.

Classification7 codes

G03F 7/12
Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g.…
G21F 1/00
Shielding characterised by the composition of the materials
Y10T 428/12361
All metal or with adjacent metals: having aperture or cut
Y10T 428/24851
Discontinuous or differential coating, impregnation or bond [e.g., artwork, printing, retouched photograph, etc.]: intermediate layer is…