US 4,049,452 AGranted

Reverse-printing method for producing cathode-ray-tube-screen structure

AssigneeRCA Corporation

InventorEdith Mayaud Nekut

Life of this patent

Estimating the term…

Loading patent…

Abstract

In the method disclosed, a supporting surface, such as the inner surface of the faceplate of the tube, is coated with a photosensitive polymeric film containing about 5 to 80 weight percent of at least one member of the group consisting of certain diol ethers and diol alkanes. Then the film is exposed to a light image to produce regions of greater solubility and regions of lesser solubility. The film regions of greater solubility are removed, and then the entire faceplate with its regions of less solubility is overcoated with a layer containing particles of screen structure material. The retained film regions and the overcoating thereon are removed leaving the screen structure adherent in the areas of greater solubility. By including a diol ether or diol alkane in the film, the exposure time may be shortened significantly without substantial loss of adherence.

Claims9

Dependent claims

A method for preparing a luminescent-screen structure of a cathode-ray tube, the steps comprising,

a. coating a support surface with a film of a polymeric material whose solubility is altered when it is exposed to radiant energy, said film containing about 5 to 80 weight percent of at least one member of the group consisting of diol alkanes having the molecular formula
HO--CH.sub.2 --(CH.sub.2).sub.m --CH.sub.2 --OH
where m is an integer in the range of 2 to 5 and diol ethers having the molecular formula
HO--CH.sub.2 --(CH.sub.2 --O--CH.sub.2).sub.n --CH.sub.2 --OH
where n is an integer in the range of 1 to 5,
b. exposing said film to an image in the form of radiant energy until the solubility of the irradiated regions thereof is selectively altered, thereby producing in said film regions of greater solublity and regions of lesser solubility,
c. removing those regions of said film with greater solubility thereby baring the areas of the support surface underlying said regions of greater solubility, while retaining those regions of said film of lesser solubility,
d. coating said bare areas of said support surface and said retained film regions with a composition containing particles of screen-structure material,
e. and then removing at least a portion of said retained film regions and the overcoating composition thereon, while retaining the overcoating composition coated on said support surface.

6 more elements

Dependencies are inferred from the claim text.