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US5122709A Expired / Lapsed US ⏱️ 0.0 years remaining

Antistatic cathode ray tube with lobe like projections and high gloss and hardness

Assignee: Hitachi Ltd
•
Filing: 1990-02-05
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Granted: 1992-06-16
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Expires: 2010-02-05
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Abstract

Abstract Disclosed in this invention are a cathode ray tube, especially glare type one, characterized in that a two-layer composite film consisting of a transparent electroconductive film and a protective film formed thereon is coated on the front panel so that surface glossiness thereof as measured by JIS Z-8741 Method 2 will become 80% or above, and a process for producing the cathode ray tube.

Inventors

  • 👤 Takao Kawamura
  • 👤 Hiromitsu Kawamura
  • 👤 Katsumi Kobara

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-01 01:02
CPC Classifications
H; H01; H01J; H01J29/00; H01J29/86; H01J29/88; C; C03; C03C; C03C17/00; C03C17/34; C03C17/3411; C03C17/3417; G; G02; G02B; G02B1/00; G02B1/10; G02B1/11; G02B1/113; H01J29/867; H01J29/868; C03C2217/00; C03C2217/40; C03C2217/42

Claims Analysis

Total Claims: 5
Claim 1
Independent Claim 109 words
A cathode ray tube having a front panel and a two-layer composite film provided on said front panel and comprising a transparent electroconductive film formed on said front panel and a protective film formed on said electroconductive film; a surface of said front panel having a plurality of crater shaped particles each having a diameter of 10 to 150 μm and a raised lobe-like peripheral projection having a width of 1 to 50 μm and a height of 0.01 to 0.5 μm, wherein said surface has a surface glossiness of 80% or above when measured according to JIS Z-8741 Method 2 and a pencil hardness of 1H or above.
Claim 2
Dependent Claim 109 words
A cathode ray tube having a front panel and a two-layer composite film provided on said front panel and comprising a transparent electroconductive film formed on said front panel and a protective film formed on said electroconductive film; a surface of said front panel having a plurality of crater shaped particles each having a diameter of 10 to 150 μm and a raised lobe-like peripheral projection having a width of 1 to 50 μm and a height of 0.01 to 0.5 μm, wherein said surface has a surface glossiness of 80% or above when measured according to JIS Z-8741 Method 2 and a pencil hardness of 1H or above.
Claim 3
Dependent Claim 19 words
A cathode ray tube according to claim 1, whose surface electric resistivity is 10 6 to 10 11 Ω/□.
Claim 4
Dependent Claim 94 words
A cathode ray tube according to claim 1, wherein said transparent electroconductive film is formed on the front panel by coating a surface of said front panel with a coating composition containing at least one of metal oxides selected from tin oxide (SnO 2 ), indium oxide (In 2 O 3 ) and antimony oxide (Sb 2 O 3 ), and an alkyl silicate (Si(OR) 4 wherein R is an alkyl group), and wherein said protective film is formed on said electroconductive film by coating it with a coating compound containing Si(OR) 4 .
Claim 5
Dependent Claim 200 words
A cathode ray tube according to claim 3, wherein the transparent electroconductive film is formed by spray- or spin-coating the front panel surface with a coating composition comprising 0.5 to 5% by weight at of least one metal oxide selected from tin oxide, indium oxide and antimony oxide which are electroconductive per se, 0.5 to 2% by weight of silicon oxide to be derived from alkyl silicate, 60 to 90% by weight of a solvent composed of ethanol and isopropanol, 1 to 15% by weight of a mixture of a catalyst necessary for hydrolysis of said silicate and water, and 5 to 20% by weight of a drying rate regulator, and then the protective film is formed on said electroconductive film by spray-coating it with a coating composition comprising 0.5 to 1.5% by weight of silicon oxide derived from alkyl silicate, 75 to 90% by weight of a solvent composed of ethanol and isopropanol, 2 to 3% by weight of a mixture of a catalyst necessary for hydrolysis and water, and 5 to 20% by weight of a drying rate regulator and wherein said transparent electroconductive film and said protective film are baked at a temperature not exceeding 200° C.

References Cited (Backward Citations)

US4590117A Cited
US4723091A Cited
US4755716A Cited
US4873120A Cited
US4900984A Cited
US4839736A Cited
US4945282A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1995-06-16 1995-12-16 1996-06-16 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1999-06-16 1999-12-16 2000-06-16 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2003-06-16 2003-12-16 2004-06-16 $7700.00 Window Closed / Lapsed

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