Abstract: The present invention relates to a method for making a viewing screen structure for a cathode-ray tube. The method includes the steps of coating a support surface with a film of a polymeric material, a suitable dichromate and a sensitizer therefor which is a chromium ion migration enhancer having a reduced sensitivity to thermal and dark hardening; exposing the film to an image in the form of radiant energy until the solubility of the irradiated regions thereof is selectively altered, thereby producing in the film regions of greater solubility and regions of lesser solubility; removing those regions of the film with greater solubility to bare portions of the underlying support surface while retaining those regions of the film with lesser solubility. The bare portions of the support surface and the retained film regions are overcoated with a composition of light-absorbing material which is adherent to the support surface.

Abstract: An apparatus for electrophotographically manufacturing a luminescent screen assembly on a substrate for use within a CRT includes a developer for developing a photoconductive layer, having a latent image thereon, with a dry-powdered, triboelectrially-charged screen structure materials. The photoconductive layer overlies a conductive layer in contact with the substrate. A grid-developing electrode is located at a distance from the photoconductive layer that is large relative to the smallest dimension of the latent image. The electrode is biased with a suitable potential to influence the deposition of the charged screen structure materials onto the latent image on the photoconductive layer. A method for electrophotographically manufacturing the screen assembly utilizing the grid-developing electrode is also disclosed.

Abstract: An apparatus for uniformly charging a photoconductive layer disposed on an interior, non-planar surface of a faceplate panel of a CRT during electrophotographic screen processing of the panel includes a corona generator having at least one corona charger and a mechanism for moving the corona charger across the non-planar surface of the faceplate panel. The corona charger substantially conforms to, and is spaced from the photoconductive layer on the non-planar, interior surface of the faceplate panel.

Abstract: A method for making a dark, adherent coating on exposed metal surfaces of a color-selection electrode assembly of a CRT includes the steps of applying a first solution of aqueous phosphoric acid to the metal surfaces of the assembly; contacting the metal surfaces with a second solution of selenium dioxide and methanol; rinsing the assembly; and then, applying a sealing solution to the surfaces of the assembly.

Abstract: A color picture tube includes an inline electron gun for generating and directing three inline electron beams along coplanar beam paths toward a screen. The gun includes a plurality of electrodes which form a beam-forming region, a prefocusing lens, and a main focusing lens for the electron beams. The prefocusing lens includes four active surfaces. At least one of the active surfaces has asymmetric prefocusing recesses formed therein.

Abstract: A method of forming an implosion protection band for a substantially rectangular CRT is disclosed. The band has at least one mounting lug comprising a base portion and an attachment portion cooperating therewith. The method includes the steps of expanding the dimensions of the band to form at least one outwardly directed concavity therein to accommodate the base portion of the mounting lug to prevent the lateral displacement thereof, attaching the mounting lug to the band and affixing the band to the CRT to compressively force the band and the base portion of the lug against the CRT.

Abstract: An implosion-resistant cathode-ray tube has an evacuated envelope with a faceplate which includes a substantially rectangularly-shaped viewing portion that extends to a peripheral sidewall. The sidewall has corners with a given radius of curvature which extends into flattened portions. An implosion protection band extends around the sidewall. A plurality of mounting lugs each having a base portion and an upstanding attachment portion cooperate with the implosion protection band. The base portion of each of the mounting lugs is disposed between the band and the sidewall. The present implosion protection band is improved over prior bands by forming a plurality of concavities in the band to accommodate the base portions of the mounting lugs. The concavities prevent lateral displacement of the mounting lugs and also maximize the contact between the implosion protection means and the sidewall of the faceplate panel.

Abstract: An implosion-resistant cathode-ray tube has an evacuated envelope with a faceplate which includes a substantially rectangularly-shaped viewing portion that extends to a peripheral sidewall. The sidewall has corners with a given radius of curvature which extends into flattened portions. An implosion protection band extends around the sidewall. At least one mounting lug having a base portion and an upstanding attachment portion cooperates with the implosion protection band. The base portion of each of the mounting lugs includes a shoulder projection which substantially conforms to the given radius of curvature of the corners of the sidewall. The attachment portion of the mounting lug is located along a section of the flattened portion of the sidewall of the faceplate panel.

Abstract: A method for uniformly beveling an inside edge of a glass article having an opening at one end thereof includes the steps of: providing a plate having a peripheral shape generally corresponding to that defined by the edge of the glass article, the plate having a beveled edge containing an abrasive material; supporting the glass article so that its inside edge is in proximity to the beveled edge of the plate; and establishing contact between the glass article and the abrasive material. An orbital, undulatory motion is induced between the bevel plate and the glass article to abrade at least a portion of the inside edge of the glass article. An apparatus for practicing the method is also described and may be used for uniformly beveling the inside edge of CRT funnels and faceplate panels.

Abstract: A method of salvaging a color selection electrode for a CRT having a coating of a compound of a heavy metal and an alkali silicate on a surface of the electrode includes the steps of immersing the electrode in a stripping solution consisting essentially of ammonium bifluoride, a suitable detergent, and water; agitating the solution to remove the coating from the electrode; rinsing, and then drying the electrode.

Abstract: In accordance with the present invention, a method of manufacturing a luminescent screen assembly on a substrate of a CRT includes the steps of providing a coating of a non-luminescent screen structure material in a predetermined pattern on the substrate and depositing a plurality of color-emitting screen structure materials on the substrate. The color-emitting screen structure materials are surrounded by the non-luminescent material. An electrostatically-charged dry-powdered resin is deposited onto the aforementioned color-emitting and non-luminescent screen structure materials and fused to form a substantially continuous film.

Abstract: A color cathode-ray tube-yoke combination comprises a color cathode-ray tube having a glass envelope and a yoke for producing magnetic fields positioned thereon. At least one semi-flexible corrective magnet is attached to a curved portion of the envelope. The novel corrective magnet is improved over prior corrective magnets by the inclusion therein of at least one portion of reduced thickness which increases the flexibility of the corrective magnet to provide conformity to the curved surface portion of the envelope.

Abstract: A cathode-ray tube-yoke combination comprises a cathode-ray tube having a glass envelope and a yoke fixedly positioned on the envelope with a body of cured polymeric material. The novel composition of the polymeric material comprises a UV-curable adhesive and UV-transmissive particles of a suitable material in an amount sufficient to accelerate the curing of the adhesive. A method to accelerate the curing is also described.

Abstract: The method of surface-treating dry-powdered phosphor particles for use in manufacturing a viewing screen for a CRT to control the triboelectric charge characteristics of the phosphor particles includes the steps of dissolving a suitable quantity of a polymeric coupling agent in a suitable solvent to form a mixture, surface-treating the phosphor particles by adding them to the mixture to provide a coating of the coupling agent thereon, and then drying the surface-treated phosphor particles. The resultant dry-powdered surface-treated phosphor particles are used to make a luminescent viewing screen for a CRT. The coupling agent controls the triboelectric charge characteristics of the phosphor particles during the electrophotographic manufacturing of the screen.

Abstract: A color picture tube, includes an envelope having a faceplate panel and a tubular neck interconnected by a funnel. A three-color phosphor screen is formed on the interior surface of the faceplate and a multi-apertured color selection electrode is spaced from the screen. An electron gun is disposed within the neck of the tube. The electron gun includes three cathodes and a plurality of spaced-apart electrodes, having substantially aligned apertures therethrough, for generating and directing three electron beams along paths toward the screen. Each of the electrodes is secured to a plurality of longitudinally extending insulative support rods by at least two oppositely disposed, integral attachment elements, each having a distal end, a proximal end and an appendage portion therebetween. The distal end of each attachment elements includes a bifurcated portion including spaced-apart grasping members to facilitate attachment to the support rods.

Abstract: The invention describes a method of manufacturing a color cathode-ray tube having a color selection electrode attached to a plurality of support studs distributed about and affixed to an interior surface portion of a faceplate panel. The manufacturing steps include: attaching a plurality of support means, each of which includes stud-engaging means, and at least one of the stud-engaging means comprising a washer having a stud-receiving aperture therethrough, to the color selection electrode; positioning the color selection electrode within the faceplate panel with the stud-engaging means positioned on the support studs; and, then, welding the washer to the support means.

Abstract: A method for the metallizing of a luminescent screen comprises the following steps:the depositing of at least one luminophor coat, comprising at least one binder, on the inner face of the screen;the depositing of a sub-layer, consisting of at least one aqueous emulsion of a water-insoluble film-forming resin;the drying of the sub-layer and the heating of this screen to a temperature greater than the minimum temperature for the formation of the film;the depositing of a finishing layer;the drying of the finishing layer;the depositing of a metallic coating on the finishing layer, and,the volatilizing of the binders of the luminiphor screen, the sub-layer and the finishing layer, wherein the sub-layer and the finishing layer are made from the same aqueous emulsions of water-insoluble film-forming resins, said emulsions having a film-forming temperature of below 45.degree. C. and giving a continuous, thin, resistant, reflective and hydrophobic film.

Abstract: A method of surface-treating dry-powdered phosphor particles to control the triboelectric charge characteristics thereof includes the steps of providing the phosphor particles with a first coating of silica, dissolving a coupling agent selected from the group consisting of silanes and titanates in a suitable solvent to form a mixture, surface-coating the silica-coated phosphor particles with the mixture to provide a second coating of the coupling agent on the phosphor particles, filtering the surface-treated particles, rinsing the surface-treated particles with the solvent, and drying the surface-treated particles. The resultant dry-powdered surface-treated phosphor particles are used to make a luminescent viewing screen for a CRT. The coupling agent overlying the silica coating controls the triboelectric charging characteristics of the phosphor particles during the electrophotographic manufacturing of the screen.

Abstract: An antistatic, glare-reducing coating, as for the surface of the viewing surface of a CRT is prepared by (a) warming a glass support surface above room temperature, (b) coating a surface of the warm support with an aqueous solution containing a lithium-stabilized silica sol and an inorganic metallic compound, and drying the deposited coating, (c) heating the glass support surface and the coating to a temperature of about 65.degree. C. for about 30 seconds, and (d) washing and then drying the coating.

Abstract: An electron gun assembly includes a plurality of cathode assemblies and a plurality of spaced successive electrodes mounted on at least two electrically insulative support rods. At least one of the electrodes comprises a deep-drawn substantially rectangular cup-shaped member having a base portion, a supporting flange portion, including a plurality of attachment tabs, and a sidewall extending therebetween. The sidewall includes a plurality of coined welding areas that provide a substantially flat welding surface having structural rigidity for securing studs thereto to facilitate attachment of the electrode to the support rods.