| 摘要 |
1,188,657. Coating apparatus. RANSBURG ELECTRO-COATING CORP. 24 April, 1967 [22 April, 1966], No. 18871/67. Heading B2L. A uniform coating of particles is applied to a surface by applying a sensitized binder to the surface to be coated, forming a cloud of the particles suspended in gas, introducing the surface into the lower portion of the cloud, effecting disposition of said particles in a downward direction onto the binder by gravity and/or electrostatic forces, activating the binder for affixing the deposited particles onto the surface, and removing the non-activated binder and non-affixed particles. An article 10, e.g. a cathode ray tube for a television receiver, after cleaning, washing with a light-sensitized binder and drying to a tacky condition, is placed onto a carriage 33 outside a chamber 11. Inside the chamber 11 air is introduced into compartment 43 from supply 45 and passes through air permeable plate 41 to generate a cloud of phosphor particles present above the plate. The carriage is then moved into the chamber, flanges 37 and 38 sealing the inlet apertures. An electrode 23 is rotated and the article is earthed at 40 through the carriage. After the phosphor particles have been deposited, the article 10 is removed, and a beam of light or like radiation is projected through a dotted imageproducing screen and onto the coated surface. The light will polymerise the polyvinyl alcohol to affix the phosphor particles. After polymerization the coating is rinsed with a solvent, e.g. water to wash away the binder and particles not in the dotted areas. After the dotted coating has dried, the process may be repeated in another fluidizing chamber charged with a phosphor having a different colour phosphorescence and in this way tubes for colour television receivers may be produced. The binder may comprise polyvinyl alcohol, and a chromic salt dissolved in isopropyl alcohol and water. |
