Cathode-ray tube and method of producing the same

• US 5,770,258 A
• Filed: 05/04/1995
• Issued: 06/23/1998
• Est. Priority Date: 12/25/1992
• Status: Expired due to Fees

• Current Assignee: Thomson Licensing (Vantiva SA)
• Original Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Inventors: Takizawa, Tomoki, Okuda, Hiroshi
• Primary Examiner(s): BELL, JANYCE A
• Application Number:
  US08/434,586
• Time in Patent Office: 1,146 Days
• Field of Search: 427/64, 427/68, 427/240, 427/126.2, 427/126.3, 427/108, 427/165, 427/167, 427/168, 427/419.3
• US Class Current: 427/64
• CPC Class Codes: H01J 2209/012 Coating
• CPC Class Codes: H01J 2229/003 Preventing or cancelling fields entering the enclosure
• CPC Class Codes: H01J 2229/89 Optical components associated with the vessel
• CPC Class Codes: H01J 2229/8915 Surface treatment of vessel or device, e.g. controlled surface roughness
• CPC Class Codes: H01J 2229/8918 by using interference effects
• CPC Class Codes: H01J 29/867 Means associated with the outside of the vessel for shielding, e.g. magnetic shields screens for shielding inside the vessel H01J29/06; magnetic shielding in general H05K9/00
• CPC Class Codes: H01J 29/868 Screens covering the input or output face of the vessel, e.g. transparent anti-static coatings, X-ray absorbing layers

Abstract

A method of producing a cathode-ray tube (CRT) of anti-static-processed type and further a cathode-ray tube which screens a leakage electric field (VLF band width). The method including the steps of forming a high-refractive transparent conductive layer, a low-refractive smooth transparent layer, and a low-refractive rough transparent layer on a faceplate of the CRT. This triple coat layer serving to reduce the weight of the CRT, minimize the deterioration of the resolution and contrast of images displayed, diminish the reflection of external light, and provide sufficient film strength for practical use.

Claims

1. A method of producing a cathode-ray tube provided with a face plate on whose outer surface a coat layer is formed, comprising the steps of:

forming a high-refractive transparent conductive layer on the surface of said face plate by spin coating;

forming a low-refractive smooth transparent layer on the surface of said high-refractive transparent conductive layer by spin coating; and

forming a low-refractive rough transparent layer on the surface of said low-refractive smooth transparent layer by spray coating;

wherein said high-refractive transparent conductive layer has a high-refractive index relative to said low-refractive smooth transparent layer and said low-refractive rough transparent layer, and said low-refractive smooth transparent layer and said low-refractive rough transparent layer have low-refractive indices relative to said high-refractive transparent conductive layer.

2. A method of producing a cathode-ray tube according to claim 1, further comprising the step of:

curing said high-refractive transparent conductive layer, low-refractive smooth transparent layer, and low-refractive rough transparent layer by baking after they are formed.

3. A method of producing a cathode-ray tube according to claim 2, wherein said high-refractive transparent conductive layer, low-refractive smooth transparent layer, and low-refractive rough transparent layer are cured by baking at 150°

to 200°

C.

4. A method of producing a cathode-ray tube according to claim 2, wherein said high-refractive transparent conductive layer and low-refractive smooth transparent layer are formed by using the same spinner in the same apparatus.

5. A method of producing a cathode-ray tube according to claim 2, further comprising:

drying said high-refractive transparent conductive layer after said high-refractive transparent conductive layer is formed and while said high-refractive transparent conductive layer is being spun.

6. A method of producing a cathode-ray tube according to claim 2, wherein

said step of forming said high-refractive transparent conductive layer includes the step of spin coating said high-refractive transparent conductive layer using a first spinner and drying said high-refractive transparent conductive layer using a drying means so as to form and dry said high-refractive transparent conductive layer;

and

said step of forming said low-refractive smooth transparent layer includes the step of spin coating said low-refractive smooth transparent layer using a second spinner.

7. A method of producing a cathode-ray tube provided with a face plate on whose outer surface a coat layer is formed, comprising the steps of;

forming a high-refractive transparent conductive layer on the outer surface of the face plate by spin coating;

forming a low-refractive smooth transparent layer on the surface of said high-refractive conductive layer by spin coating, said low-refractive smooth transparent layer having a low-refractive index relative to said high-refractive transparent conductive layer and said high-refractive transparent conductive layer having a high-refractive index relative to said low-refractive smooth transparent layer; and

curing said high-refractive transparent conductive layer and said low-refractive smooth transparent layer by baking after forming said high-refractive transparent conductive layer and said low-refractive smooth transparent layer.

8. A method of producing a cathode-ray tube according to claim 7, wherein said high-refractive transparent conductive layer and low-refractive smooth transparent layer are cured by baking at 150°

to 200°

C.

9. A method of producing a cathode-ray tube according to claim 7, wherein said high-refractive transparent conductive layer and low-refractive smooth transparent layer are formed by using the same spinner in the same apparatus.

10. A method of producing a cathode-ray tube according to claim 7, further comprising:

drying said high-refractive transparent conductive layer after said high-refractive transparent conductive layer is formed and while said high-refractive transparent conductive layer is being spun.

11. A method of producing a cathode-ray tube according to claim 7, wherein:

said step of forming said high-refractive transparent conductive layer includes the step of spin coating said high-refractive transparent conductive layer using a first spinner and drying said high-refractive transparent conductive layer using a drying means so as to form and dry said high-refractive transparent conductive layer; and

said step of forming said low-refractive smooth transparent layer includes the step of spin coating said low-refractive smooth transparent layer using a second spinner.