Process for making color television screens by electrophoretic deposition

Claim 2

For use in the production of a striped-screen television image display faceplate, a process for electrophoretically depositing patterns of image-related compounds on said faceplate, the process comprising: depositing a pattern of groups of periodically repeating electrically conductive stripes on said faceplate, said stripes in said groups being of a predetermined graduated length from relatively long to relatively short; electrically exciting by means of conductive contact strips with a charge of a first polarity both ends of said relatively long stripes during immersion of said faceplate in an electrolytic bath including an image-related compound having particles charged with a potential of a second polarity opposite to said polarity for electrophoretic deposition of said particles on said stripes; serially electrically exciting both ends of stripes of successively shorter lengths, accompanying each such exciting with a different bath including a different image-related compound for electrophoretic deposition on the respective stripes; whereby, by electrically contacting both ends of said conductive stripes, the effect of a single discontinuity in electrical conductivity of any of said stripes is nullified as any stripe having such a discontinuity is electrophoretically coated along its entire length with said compound.

Claim 3

For use in the production of a striped-screen shadow-mask-type color television cathode ray tube, a process for electrophoretically depositing patterns of image-related compounds on the inner surface of the faceplate of said tube, the process comprising: depositing on said inner surface of said faceplate periodically repeating patterns of electrically conductive stripes, said stripes being grouped in triads, with each triad comprising a relatively long stripe, a relatively short stripe, and a stripe having a length intermediate thereto; electrically exciting with a charge of a first polarity both ends of all of said relatively long stripes, using for excitation at least one electrically conductive contact strip; immersing said faceplate in an electrolytic bath including an image-related compound having particles charged with a potential of a second polarity opposite to said first polarity, for electrophoretic deposition of said particles on the respective stripes; twice repeating the aforedescribed exciting and immersing steps to electrophoretically deposit second and third image-related compounds on respectively associated second and third patterns of conductive stripes, including serially electrically exciting with a contact strip both ends of said stripes of intermediate length and said relatively short stripes, accompanying each such contacting by an immersion in a bath including said second and third compounds respectively for electrophoretic deposition on the respective conductive stripes; whereby, by electrically exciting both ends of said conductive stripes, the effect of a single discontinuity in electrical conductivity of any of said stripes is nullified as any stripe having such a discontinuity is electrophoretically coated along its entire length with said compound.

Claim 4

For use in the production of a striped-screen shadow-mask-type color television cathode ray tube, a process for electrophoretically depositing patterns of image-related compounds on the inner surface of the faceplate of said tube, the process comprising: depositing on said inner surface of said faceplate periodically repeating patterns of electrically conductive stripes, said stripes being grouped in triads, with each triad comprising a relatively long stripe, a relatively short stripe, and a stripe having a length intermediate thereto; electrically exciting with a charge of a first polarity both ends of all of said relatively long stripes, using for excitation at least one electrically conductive contact strip; immersing said faceplate in an electrolytic bath including an image-related compound having particles charged with a potential of a second polarity opposite to said first polarity, for electrophoretic deposition of said particles on the respective stripes; twice repeating the aforedescribed exciting and immersing steps to electrophoretically deposit second and third image-related compounds on respectively associated second and third patterns of conductive stripes, including serially electrically exciting with a contact strip both ends of said stripes of intermediate length and said relatively short stripes, accompanying each such contacting by an immersion in a bath including said second and third compounds respectively for electrophoretic deposition on the respective conductive stripes; whereby, by electrically exciting both ends of said conductive stripes, the effect of a single discontinuity in electrical conductivity of any of said stripes is nullified as any stripe having such a discontinuity is electrophoretically coated along its entire length with said compound.

Claim 5

For use in the production of a striped-screen shadow-mask-type color television cathode ray tube, a process for electrophoretically depositing a pattern of phosphor compounds on the inner surface of the faceplate of said tube, using to establish said pattern a slot shadow mask mated with said faceplate in precise registration thereto by disengageable mask mounting means, the process comprising: depositing on said inner surface an electrically conductive coating; depositing on said coating a negative-working photopolymer; engaging said shadow mask to said faceplate by said mask-mounting means; selectively exposing said surface to a source of light actinic to said photo-polymer through said shadow mask to establish a latent, periodically repeating pattern of conductive stripes in said photo-polymer; said stripes being grouped in triads, with each triad comprising a relatively long stripe, a relatively short stripe, and a stripe having a length intermediate thereto; disengaging said shadow mask from said faceplate; fixing the exposed latent pattern of stripes and removing exposed areas of said surface to leave said pattern of conductive stripes on said inner surface of said faceplate; electrically exciting with a charge of a first polarity both ends of all of said relatively long stripes, using for excitation at least one electrically conductive conformable contact strip; immersing said faceplate in an electrolytic bath including an image-related compound having particles charged with a potential of a second polarity opposite to said first polarity for electrophoretic deposition of said particles on the respective stripes; twice repeating the aforedescribed exciting and immersing steps to electrophoretically deposit second and third image-related compounds on respectively associated second and third patterns of conductive stripes, including serially electrically exciting with a contact stripe both ends of said stripes of intermediate length and said relatively short stripes, accompanying each such contacting by an immersion in a bath including said second and third compounds respectively for electrophoretic deposition on the respective conductive stripes; stripping away chemically said pattern of conductive stripes; whereby, by electrically exciting both ends of said conductive stripes, the effect of a single discontinuity in electrical conductivity of any of such stripes is nullified as any stripe having such a discontinuity is electrophoretically coated along its entire length with said compound.

Claim 6

For use in the production of a striped-screen shadow-mask-type color television cathode ray tube, a process for electrophoretically depositing a pattern of phosphor compounds on the inner surface of the faceplate of said tube, using to establish said pattern a slot shadow mask mated with said faceplate in precise registration thereto by disengageable mask mounting means, the process comprising: depositing on said inner surface an electrically conductive coating; depositing on said coating a negative-working photopolymer; engaging said shadow mask to said faceplate by said mask-mounting means; selectively exposing said surface to a source of light actinic to said photo-polymer through said shadow mask to establish a latent, periodically repeating pattern of conductive stripes in said photo-polymer; said stripes being grouped in triads, with each triad comprising a relatively long stripe, a relatively short stripe, and a stripe having a length intermediate thereto; disengaging said shadow mask from said faceplate; fixing the exposed latent pattern of stripes and removing exposed areas of said surface to leave said pattern of conductive stripes on said inner surface of said faceplate; electrically exciting with a charge of a first polarity both ends of all of said relatively long stripes, using for excitation at least one electrically conductive conformable contact strip; immersing said faceplate in an electrolytic bath including an image-related compound having particles charged with a potential of a second polarity opposite to said first polarity for electrophoretic deposition of said particles on the respective stripes; twice repeating the aforedescribed exciting and immersing steps to electrophoretically deposit second and third image-related compounds on respectively associated second and third patterns of conductive stripes, including serially electrically exciting with a contact stripe both ends of said stripes of intermediate length and said relatively short stripes, accompanying each such contacting by an immersion in a bath including said second and third compounds respectively for electrophoretic deposition on the respective conductive stripes; stripping away chemically said pattern of conductive stripes; whereby, by electrically exciting both ends of said conductive stripes, the effect of a single discontinuity in electrical conductivity of any of such stripes is nullified as any stripe having such a discontinuity is electrophoretically coated along its entire length with said compound.