Abstract: In accordance with the present invention, a method of electro-photographically manufacturing a luminescent screen assembly on an interior surface of a faceplate panel 12 for a color CRT 10 includes the steps of coating the interior surface of the faceplate panel with a volatilizable, organic conductive solution to form an organic conductive (OC) layer 32, and overcoating the OC layer with a volatilizable, organic photoconductive solution to form an organic photoconductive (OPC) layer 34. The step of overcoating the OC layer to form the OPC layer is improved by the substeps of: grounding the OC layer; providing an organic photoconductive (OPC) solution comprising a resin, an electron donor material and electron acceptor material, and a suitable solvent; and spraying electrostatically-charged droplets of the OPC solution onto the OC layer, with at least one electrostatic spray gun 47, to provide an OPC layer, having uniform thickness, overlying the OC layer.

Abstract: A method of manufacturing a luminescent screen assembly on an interior surface of a faceplate panel 12 for a color CRT 10 includes the steps of uniformly applying a solution of a material to form an organic conductive (OC) layer and overcoating the OC layer with a solution to form an organic photoconductive (OPC) layer, on the interior surface of the faceplate panel. The OPC layer 34 is conditioned by directing a stream of dry gas thereon to warm the OPC layer to a preheat temperature, while maintaining the panel at a panel temperature less than the preheat temperature. The OPC layer is exposed to IR radiation to rapidly increase the temperature of the OPC layer to a curing temperature, greater than the preheat temperature, to remove some of the volatilizable constituents from the OPC layer, without substantially increasing the temperature of the panel.

Abstract: In accordance with the present invention, an apparatus for developing a latent image formed on a photoreceptor, which is deposited on an interior surface of an output window of a display device, is disclosed. The developing apparatus includes a developing chamber, having a support surface for supporting the output window, a screen structure material reservoir for storing, deagglomerating and feeding the screen structure material, and a triboelectric gun assembly communicating with the reservoir. The gun assembly triboelectric charges and imparts a desired charge polarity to the screen structure material. The gun assembly further includes at least one material dispersing nozzle spaced from the support surface for distributing the charged material for deposition onto the latent image.

Abstract: In accordance with the present invention, a method of electrophotographically manufacturing a luminescent screen assembly for a color CRT 10 on an interior surface of a faceplate panel 12 is described. A volatilizable organic conductive (OC) layer 32 is provided on the interior surface of the panel and a volatilizable organic photoconductive (OPC) layer 34 overlies the OC layer 32.

Abstract: In accordance with the present invention, a method of electro-photographically manufacturing a luminescent screen assembly for a color CRT 10 on an interior surface of a faceplate panel 12 is described. A volatilizable, organic conductive (OC) layer 32 is provided on the interior surface of the panel and a volatilizable, organic photoconductive (OPC) layer 34 overlies the OC layer. The method includes the steps of: establishing a substantially uniform electrostatic charge on the OPC layer; exposing selected areas of the OPC layer to visible light to affect the charge thereon; developing the selected areas of the OPC layer with a triboelectrically charged dry-powdered, screen structure materials; fixing the screen structure materials to the underlying OPC layer with a suitable fixative; filming the screen structure materials; aluminizing the screen; and baking the aluminized screen.

Abstract: In accordance with the present invention, a method of electrophotographically manufacturing a luminescent screen assembly on an interior surface of a faceplate panel 12 of a color CRT 10 comprises the steps of coating the interior surface of the panel with a volatilizable, organic conductive material to form an organic conductive (OC) layer 32, and overcoating the OC layer 32 with a volatilizable, photoconductive material to form an organic photoconductive (OPC) layer 34. Then, a substantially uniform voltage is established on the OPC layer 34, and selected areas of the OPC layer 34 are exposed to visible light to affect the voltage thereon, without affecting the voltage on the unexposed area of the OPC layer 34. Next, triboelectrically charged, light-absorbing screen structure material is deposited onto the unexposed area of the OPC layer 34 to form a substantially continuous matrix 23 of light-absorbing material having open areas therein.

Abstract: In accordance with the present invention, a method of electrophotographically manufacturing a luminescent screen assembly on a photoreceptor disposed on an interior surface of a faceplate panel for a color CRT includes the steps of: charging the photoreceptor to establish a substantially uniform electrostatic voltage thereon; positioning the panel on an exposure device having a light source therein; exposing selected areas of the photoreceptor to visible light from the light source to affect the voltage thereon, without affecting the voltage on the unexposed area of the photoreceptor; and depositing a triboelectrically charged, first color-emitting phosphor onto the selected areas of the photoreceptor. The charging, positioning, exposing and depositing steps are repeated for a second and a third triboelectrically charged, color-emitting phosphor.

Abstract: The method of electrophotographically manufacturing a screen assembly on an interior surface of a viewing faceplate of a panel for a color CRT, according to the present invention, includes the steps of forming a volatilisable organic conductive layer on the interior surface of the viewing faceplate and overcoating the organic conductive layer with an organic photoconductive solution to form a volatilizable organic photoconductive layer. The conductive solution, comprising a polyelectrolyte and a diluent, is applied to the interior surface of the viewing faceplate by spraying, to form the conductive layer.

Abstract: A solution for making a wear-resistant conductive contact patch for a faceplate panel of a color CRT which facilitates the electrophotographic manufacturing of a luminescent screen on the panel consists essentially of, in weight percent, solvent 22 to 70, conductive material 62 to 21, and the balance being other compatible additives.

Abstract: The method of electrophotographically manufacturing a luminescent screen on a substrate of a color CRT, according to the present invention, includes the steps of forming a photoreceptor by sequentially coating the substrate to form a conductive layer and an overcoating of a photoconductive layer, establishing an electrostatic charge on the photoconductive layer, and exposing selected areas of the photoconductive layer to visible light to affect the charge thereon. Then the photoconductive layer is developed by the application of suitable triboelectrically charged, dry-powdered screen structure materials. The improved process provides at least one wear-resistant, conductive contact patch on a peripheral portion of a surface of the substrate. The contact patch has a first portion which underlies at least one of the layers of the photoreceptor and is in electrical contact with the conductive layer, and a second portion which extends from the photoreceptor.

Abstract: The method of electrophotographically manufacturing a luminescent screen assembly on a substrate for use within a CRT, according to the present invention, includes the steps of: forming a conductive layer on the substrate; overcoating the conductive layer with a photoconductive solution comprising an organic polymeric material, a suitable photoconductive dye, a plasticizer and a solvent to form a photoconductive layer; and, then, establishing an electrostatic charge on the photoconductive layer. Selected areas of the photoconductive layer are exposed to visible light to affect the charge thereon, and the photoconductive layer is developed with charged screen structure material. The improved method utilizes a dialkyl phthalate plasticizer which is selected from the group consisting of dibutylphthalate (DBP), dioctylphthalate (DOP), and diundecylphthalate (DUP).

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: The method of electrophotographically manufacturing a luminescent screen assembly on a substrate of a CRT, according to the present invention, includes the steps of coating the substrate with a conductive layer and overcoating the conductive layer with a photoconductive layer, establishing an electrostatic charge on the photoconductive layer, and exposing selected areas of the photoconductive layer to visible light to affect the charge thereon. Then, the selected areas of the photoconductive layer are developed with triboelectrically charged, dry-powdered, surface-treated screen structure materials. The improved process increases the adherence of the surface-treated materials to the photoconductive layer by contacting the surface-treated materials with a solvent to render the photoconductive layer and the materials tacky.

Abstract: The method comprises applying to a surface to be etched a coating of a borax-free, low dichromate, casein photoresist liquid composition comprising an acid-precipitated casein, sodium hydroxide as an alkalizing agent, an alkali dichromate photosensitizer and water. The composition has a pH in the range of 6.0 to 7.0, and reduced quantities of the alkalizing agent and photosensitizer compared to prior coating compositions.

Abstract: A method for producing a stencil of PVA (polyvinyl alcohol) including applying and heat-drying to a surface a coating of an aqueous composition of PVA and dichromate sensitizer, and then exposing and developing the dried coating. The aqueous composition includes a fluorescein-type dye or combination of dyes in such proportions as to substantially reduce heat-hardening of the dried coating. The method is particularly useful for preparing etch-resistant stencils used in preparing precision-etched products, such as apertured masks for use in cathode-ray tubes.

Abstract: In a method for removing insolubilized polyvinyl alcohol portions from the surface of a body on which it is adhered, the step of contacting said stencil and surface with an aqueous stripping solution containing at least one nonoxidizing mineral acid, such as hydrochloric acid and phosphoric acid, in concentration that is effective to remove said portions with at most light mechanical action.