US4340839A
Expired / Lapsed
US
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Zinc sulfide ceramic material and cathode ray tubes using the same
Assignee: Panasonic Holdings Corp
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Filing: 1979-12-20
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Granted: 1982-07-20
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Expires: 1999-12-20
Abstract
Abstract Highly densed zinc sulfide ceramic materials, which essentially comprise zinc sulfide and alkali metals and/or alkaline earth metals and impurities acting as luminescent center, and which show a high brightness of cathode luminescence under irradiation of electron beam having a low energy, are easily made in the form of the sintered material, by heating the mixture of the said materials in inert or sulfuring atmosphere.
Inventors
- 👤 Yosuke Fujita
- 👤 Fumio Fukushima
- 👤 Yoji Fukuda
- 👤 Tsuneharu Nitta
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 03:55
CPC Classifications
C; C09; C09K; C09K11/00; C09K11/08; C09K11/56; C09K11/562; C09K11/567; C04; C04B; C04B35/00; C04B35/515; C04B35/547; C09K11/0805; C09K11/0811; C09K11/0816; C09K11/565; H; H01; H01J; H01J29/00; H01J29/02; H01J29/10; H01J29/18; H01J29/28
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
39 words
Particles of zinc sulfide sintered ceramic material adapted for use as the luminescent screen in a cathode ray tube consisting essentially of zinc sulfide and at least one element selected from the group consisting of Ca, Sr and Ba.
Claim 2
Dependent Claim
39 words
Particles of zinc sulfide sintered ceramic material adapted for use as the luminescent screen in a cathode ray tube consisting essentially of zinc sulfide and at least one element selected from the group consisting of Ca, Sr and Ba.
Claim 3
Dependent Claim
16 words
The zinc sulfide sintered ceramic material in accordance with claim 1 further containing luminescent impurities therein.
Claim 4
Dependent Claim
74 words
Particles of zinc sulfide sintered ceramic material adapted for use as the luminescent screen in a cathode ray tube, said material consisting essentially of zinc sulfide; at least one element selected from the group consisting of Ca, Sr and Ba; at least one activator selected from the group consisting of Au, Ag, Cu, Mn and Tb; and at least one co-activator selected from the group consisting of Al, Ga, In, Cl, Br and I.
Claim 5
Dependent Claim
74 words
Particles of zinc sulfide sintered ceramic material adapted for use as the luminescent screen in a cathode ray tube, said material consisting essentially of zinc sulfide; at least one element selected from the group consisting of Ca, Sr and Ba; at least one activator selected from the group consisting of Au, Ag, Cu, Mn and Tb; and at least one co-activator selected from the group consisting of Al, Ga, In, Cl, Br and I.
Claim 6
Dependent Claim
34 words
The zinc sulfide sintered ceramic material in accordance with claim 1 or 3 wherein said at least one element is present in an amount of from 0.02 to 3.0 percent of the zinc metal.
Claim 7
Dependent Claim
21 words
The zinc sulfide sintered ceramic material in accordance with claim 1 or 3 wherein said at least one element is Ba.
Claim 8
Dependent Claim
41 words
A cathode ray tube including as the luminescent screen a layer of particles of a zinc sulfide sintered ceramic material which consists essentially of zinc sulfide and at least one element selected from the group consisting of Ca, Sr and Ba.
Claim 9
Dependent Claim
41 words
A cathode ray tube including as the luminescent screen a layer of particles of a zinc sulfide sintered ceramic material which consists essentially of zinc sulfide and at least one element selected from the group consisting of Ca, Sr and Ba.
Claim 10
Dependent Claim
14 words
The cathode ray tube in accordance with claim 6 further containing luminescent impurities therein.
Claim 11
Dependent Claim
75 words
A cathode ray tube including as the luminescent screen therein a layer of particles of a zinc sulfide sintered ceramic material which consists essentially of: zinc sulfide; at least one element selected from the group consisting of Ca, Sr and Ba; at least one activator selected from the group consisting of Au, Ag, Cu, Mn and Tb; and at least one co-activator selected from the group consisting of Al, Ga, In, Cl, Br and I.
Claim 12
Dependent Claim
75 words
A cathode ray tube including as the luminescent screen therein a layer of particles of a zinc sulfide sintered ceramic material which consists essentially of: zinc sulfide; at least one element selected from the group consisting of Ca, Sr and Ba; at least one activator selected from the group consisting of Au, Ag, Cu, Mn and Tb; and at least one co-activator selected from the group consisting of Al, Ga, In, Cl, Br and I.
Claim 13
Dependent Claim
22 words
The cathode ray tube of claim 8 wherein said luminescent screen has an aluminum film less than 1,000 Angstroms in thickness thereon.
Claim 14
Dependent Claim
31 words
The cathode ray tube of claims 6, 8 or 9 wherein said at least one element is present in an amount of from 0.02 to 3.0 percent of the zinc metal.
Claim 15
Dependent Claim
18 words
The cathode ray tube of claim 6, 8 or 9 wherein said at least one element is Ba.
Claim 16
Dependent Claim
93 words
A luminescent screen adapted for use in a cathode ray tube, said screen comprising: a smooth, thin film of a dense, homogeneous zinc sulfide sintered ceramic material consisting essentially of: zinc sulfide; Ca, Sr, Ba or mixtures thereof present in an amount of from 0.02 to 3.0 percent of the zinc metal; Au, Ag, Cu, Mn, Tb or mixtures thereof as an activator; Al, Ga, In, Cl, Br, I or mixtures thereof as co-activator; and an aluminum conductive/reflection film of less than 1,000 Angstroms in thickness deposited on said film of ceramic material.
Claim 17
Dependent Claim
93 words
A luminescent screen adapted for use in a cathode ray tube, said screen comprising: a smooth, thin film of a dense, homogeneous zinc sulfide sintered ceramic material consisting essentially of: zinc sulfide; Ca, Sr, Ba or mixtures thereof present in an amount of from 0.02 to 3.0 percent of the zinc metal; Au, Ag, Cu, Mn, Tb or mixtures thereof as an activator; Al, Ga, In, Cl, Br, I or mixtures thereof as co-activator; and an aluminum conductive/reflection film of less than 1,000 Angstroms in thickness deposited on said film of ceramic material.
Claim 18
Dependent Claim
47 words
The luminescent screen of claim 12 wherein the aluminum conductive layer is no greater than 200 Angstroms in thickness and said screen exhibits a relative emission brightness of about 100% when subjected to an acceleration voltage in the range of about 2 kV to about 10 kV.
Claim 19
Dependent Claim
27 words
The luminescent screen of claim 12 wherein the relative density, expressed as a percentage of actual density over theoretical density, if from about 92% to about 97%.
Claim 20
Dependent Claim
24 words
The luminescent screen of claim 12 or 14 wherein the amount of Ca, Sr, Ba or mixtures thereof is from 0.1 to 0.3 percent.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-07-19 | 1986-01-18 | 1986-07-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-07-19 | 1990-01-18 | 1990-07-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-07-19 | 1994-01-18 | 1994-07-20 | $7700.00 | Window Closed / Lapsed |