THE SCREEN IS COVERED WITH A WATER-SOLUBLE COATING MATERIAL COMPRISING A NEGATIVE PHOTOSENSITIVE RESIST AND AN INHIBITOR TO RENDER THE RESIST UNRESPONSIVE TO ULTRAVIOLET LIGHT. AN ADDITIVE, SUCH AS DYE THAT MAY BE BLEACHED OR ACTIVATED BY EXPOSURE TO A VISIBLE LIGHT WAVELENGTH, IS ALSO INCLUDED IN THE COATING TO COUNTERACT THE EFFECT OF THE INHIBITOR WHEN ACTIVATED BY EXPOSURE. THE SCREEN, COATED WITH THIS MATERIAL, IS FIRST EXPOSED TO THE VISIBLE RADIATION FROM ONE COLOR POSITION AND THROUGH A SHADOW MASK HAVING APERTURES LARGER THAN THE PHOSPHOR DOTS OF THE SCREEN. THE SCREEN IS THEN EXPOSED TO ULTRAVIOLET, AGAIN THROUGH THE SHADOW MASK BUT FROM A SECOND COLOR POSITION AND RESULTS IN ELEMENTAL AREAS OF THE COATING MATERIAL, WHERE THE TWO EXPOSURE PATTERNS OVERLAP, BEING RENDERED INSOLUBLE. THE COATING PATTERN IS DEVELOPED BY WASHING THE SCREEN WITH WATER.

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