Patent US4734615A successfully refreshed from Google Patents.
US4734615A
Expired / Lapsed
US
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Color cathode ray tube
Assignee: Toshiba Corp
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Filing: 1986-07-11
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Granted: 1988-03-29
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Expires: 2006-07-11
Abstract
Abstract The shadow mask of a color cathode ray tube is arranged in the vicinity of a phosphor screen. The shadow mask is provided with through-holes that select the electron beams emitted from the electron guns. A layer comprising, as a filler, one or other of a metal, metal oxide, metal carbide, metal nutride, or a mixture of two or more of these, for example zirconium powder and, as a binder, one of an amorphous metal oxide compound, amorphous metal hydroxide compound or a mixture of these, for example silicon oxide, is formed on the surface of the shadow mask. This layer increases thermal radiation of the shadow mask, reduces electron scattering, and raises the residual emissivity.
Inventors
- 👤 Norio Koike
- 👤 Hidemi Matsuda
- 👤 Kiyoshi Tokita
- 👤 Kaneharu Kida
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 04:32
CPC Classifications
H; H01; H01J; H01J9/00; H01J9/02; H01J9/14; H01J29/00; H01J29/02; H01J29/06; H01J29/07; H01J2229/00; H01J2229/07; H01J2229/0727; H01J2229/0777; H01J2229/0783
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
94 words
A color cathode ray tube comprising: a phosphor screen; a shadow mask with a large number of apertures, arranged in the vicinity of said phosphor screen; an electron gun generating an electron beam passing through said apertures of said shadow mask to excite said phosphor screen; wherein said shadow mask is coated with a layer consisting essentially of a binder selected from the group consisting of amorphous metal oxide, amorphous metal hydroxide and mixture thereof; and a filler selected from the group consisting of metal, metal oxide, metal carbide, metal nitride and mixture thereof.
Claim 2
Dependent Claim
94 words
A color cathode ray tube comprising: a phosphor screen; a shadow mask with a large number of apertures, arranged in the vicinity of said phosphor screen; an electron gun generating an electron beam passing through said apertures of said shadow mask to excite said phosphor screen; wherein said shadow mask is coated with a layer consisting essentially of a binder selected from the group consisting of amorphous metal oxide, amorphous metal hydroxide and mixture thereof; and a filler selected from the group consisting of metal, metal oxide, metal carbide, metal nitride and mixture thereof.
Claim 3
Dependent Claim
25 words
The color cathode ray tube according to claim 1 wherein said layer is formed on a surface of said shadow mask facing said electron gun.
Claim 4
Dependent Claim
23 words
The color cathode ray tube according to claim 1 wherein said binder is a product of heat treatment of a metal alkoxide compound.
Claim 5
Dependent Claim
31 words
The color cathode ray tube according to claim 3 wherein metal of said metal alkoxide compound is one selected from the group consisting of silicon, titanium, aluminum, zirconium and mixture thereof.
Claim 6
Dependent Claim
37 words
The color cathode ray tube according to claim 1 wherein said filler is one selected from the group consisting of silicon carbide, manganese oxide, chromium oxide, iron oxide, cobalt oxide, copper oxide, zircon, zirconium and mixture thereof.
Claim 7
Dependent Claim
21 words
The color cathode ray tube according to claim 1 wherein the thickness of said layer is 1 micron to 30 micron.
Claim 8
Dependent Claim
16 words
The color cathode ray tube according to claim 1 wherein the filler is dark in color.
References Cited (Backward Citations)
US3760214A
Cited
US4558252A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-03-29 | 1991-09-28 | 1992-03-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-03-29 | 1995-09-28 | 1996-03-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-03-29 | 1999-09-28 | 2000-03-29 | $7700.00 | Window Closed / Lapsed |