KR100298387B1 - Color cathod ray tube with electrificationn and reflection preventing function - Google Patents

Abstract

PURPOSE: A color cathode ray tube having an electrification function and a reflective function is provided to improve transmissivity by lowering a surface resistance of a panel. CONSTITUTION: A cathode ray tube includes a panel(1) having an image display side. A conductive layer(14) is formed on a face of the panel(1). The conductive layer(14) is formed with Sn, F, and In2O3. A low reflective layer(15) is formed on the conductive layer(14). A surface resistance and a transmissivity are improved by using the conductive layer(14). The transmissivity is improved by using the low reflective layer(15). A conductive tape is adhered on a side of the above structure. The conductive layer(14) is formed with Sn of 1 to 10 weight percents, F of 1 to 30 weight percents, and In2O3 of the remaining weight percents.

Description

Color cathod ray tube with electrificationn and reflection preventing function}

The present invention relates to the formation of a coating film having an antistatic and antireflection function on an image display surface of a cathode ray tube, and is particularly suitable for lowering surface resistance to minimize electrostatic charge and having good transmittance characteristics.

Figure 1 shows a longitudinal cross-sectional view of a conventional cathode ray tube, a panel (1) with a fluorescent film formed on the inner surface of the glass and a funnel (2) coated with conductive graphite is sealed with each other by fusion glass, funnel An electron gun 7 for generating an electron beam is mounted on the neck portion 3 of the neck. A shadow mask 4, which is a color-selective electrode, is supported by the frame 5 inside the panel, and an electron beam is provided on the outer circumferential surface of the funnel. A deflection yoke 8 for deflecting from side to side is mounted.

The color CRT configured as described above inputs an image signal to the electron gun 7 so that hot electrons are emitted from the cathode of the electron gun, and the emitted electrons are accelerated and focused toward the panel by a voltage applied from each electrode of the electron gun.

At this time, the path of the electron beam 9 is adjusted by the magnetic field of the magnet mounted on the neck of the funnel 2, and the adjusted electron beam is scanned on the inner surface of the panel 1 by the deflection yoke 8. The deflected electron beam passes through the solt of the shadow mask 4 coupled to the inner frame 5 of the panel, and color separation is performed. The selected electron beam collides with each fluorescent film on the inner surface of the panel 1 to emit an image signal. To reproduce.

In order to prevent the electron beam from being deflected by the influence of geomagnetism in the electron beam passing through the slot of the shadow mask and reaching the fluorescent film, the rear surface of the frame 5 to which the shadow mask 7 is coupled is viewed from the panel 1 side. A geomagnetic shielding material (Inner Shield is called) (6) is attached.

Since the panel 1 made of glass in the above structure strongly reflects external light, it is difficult to see an image formed on the panel. When the power is applied to the cathode ray tube and is cut off, a high-voltage anode voltage is applied or blocked on the inner surface of the panel, in which case the electrostatic Due to the derivative, a static charge of a potential opposite to the internal high pressure may be charged on the outer surface of the panel of the insulator.

This may be severely impacted by high pressure static electricity when the user touches, and it may be difficult to see the image due to the adhesion of dust on the outside of the panel.

Accordingly, in order to prevent charging, in recent years, as shown in FIG. 2, a transparent conductive film 10 is formed on the outer surface of the panel 1 and grounded as a conductive tape 11, or hydrolysis of the alkoxy silane applied to the panel surface is prevented. used in this case formed in the Si-O-Si chains of the minor hydroxy _(- OH) and leave the room to release by using the hygroscopicity of the hydroxy lower the surface resistance impart conductivity (Japanese Patent Publication 61-118932 cow), a liquid The conductive solution is spray-coated and heat-treated at 400 ° C. or higher to form a transparent conductive film (Japanese Utility Publication No. 49-2411), or to form a multilayer thin film by chemical vacuum deposition or sputtering deposition to prevent external light reflection on the panel surface. Japanese Patent Application Laid-Open No. 62-154540, or a method of attaching a separate panel on which a multilayer reflective film is formed by chemical vacuum deposition or sputtering deposition is used.

In addition, in Asahi, Japan, a transparent conductive film is formed with a mixture solution of zirconium oxide, silicon oxide, and conductive tin oxide on the panel face, and the surface resistance and glossiness characteristics are improved (Japanese Patent Publication H04-65384). It is widely used.

Figure 3 shows another structure of the conventional cathode ray tube, the charging phenomenon generated by the electrostatic induction when the power applied to the cathode ray tube on / off lowers the surface resistance of the outer surface of the panel 1 to prevent the movement of charged charge The conductive film 12 is easily formed so as to be erased quickly when static electricity is generated, and the reflection film 13 made of glass layers having different refractive indices is formed on the surface of the image to prevent reflection, thereby interfering with the light reflected from each layer. The effect is used to lower the reflectance.

The conductive film 12 is a sol-gel liquid of the antimony (Sb) -doped tin oxide (SnO ₂ ) component is injected into the surface of the CRT, coated by a rotary coating method and then fired to form a coating film.

At this time, the surface resistance is 10 ^{7 ~ 8} (Ω / □) or less, and ELF BAND with 5㎑-2㎑ from the CRT and 2 브라운 ~ 400 according to the TCO standard. The resistance should be lowered to the level of 10 ³ (Ω / □) or less required to minimize the electromagnetic waves of the VLF BAND.

On the other hand, although the conductive film and the low reflection film may be formed using a conventional conductive material, the transmittance is lowered due to the difference in refractive index with the panel, and a dye may be added to improve contrast, thereby increasing the transmittance even more. There is a problem of deterioration.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and by appropriately controlling the alloy composition of the conductive film and forming a low reflection film on the conductive film, the surface resistance on the panel surface is reduced to minimize the electrostatic charges charged. The purpose is to have an image display surface of a cathode ray tube suitable for improving transmittance.

1 is a schematic diagram of a conventional color cathode ray tube

2 is a schematic diagram of a conventional cathode ray tube having a conductive film formed thereon;

3 is a schematic diagram of a conventional cathode ray tube for antistatic and antireflection

4 is a schematic diagram of a cathode ray tube according to the present invention;

5 is a state diagram showing a measuring point for the surface electrical resistance characteristics test

Explanation of symbols for main parts of the drawings

1 panel 14 conductive film

15: low reflection film

The present invention for achieving the above object is a cathode ray tube having a panel showing an image display surface as shown in Fig. 4 shown in the embodiment, the tin (Sn), fluorine (F) and indium oxide ( A conductive film 14 composed of In ₂ O ₃ is formed, and a cathode ray tube having a low reflection film 15 formed thereon is formed.

Then, the conductive tape 11 shown in FIG. 2 is attached to the side.

The conductive film 14 has a surface resistance and transmittance by doping a small amount of fluorine (F) to indium oxide (In ₂ O ₃ ) doped with tin (Sn), that is conventionally used to improve the antistatic properties, i.e. The characteristics were improved, and the low reflection film 15 was formed thereon to improve the transmittance.

In the composition of the conductive film 14, tin (Sn) is 1 to 10% by weight, fluorine (F) is 1 to 30% by weight, and the remainder is indium oxide (In ₂ O ₃ ).

When the content of tin (Sn) is 1 wt% or less, sufficient conductivity is not imparted to indium oxide (In ₂ O ₃ ), and when it is 10 wt% or more, conductivity does not appear due to excess.

Preferably it is 3-7 weight% of the said content.

As the fluorine (F), fluoride containing a conductive metal is preferably used, and tin fluoride and indium fluoride are preferably used.

If the content of fluorine (F) is 1.0% by weight, its content is insignificant and there is no increase in transmittance, and in the case of more than 30% by weight, the transmittance is lowered due to excessive addition, preferably 5 to 20% by weight.

The method of forming the coating film includes indium oxide (In ₂ O ₃ ) doped with tin (Sn) and fluorine (F), that is, the ITOF fine particles contain silicon oxide or silicon oxide-titanium oxide (SiO ₂ -TiO ₂ ) fine particles. It is good to apply to a predetermined thickness using the colloidal solution.

At this time, ITOF which is a ceramic electroconductive powder uses the thing whose average particle diameter is 70 nm or less.

If the thickness is 70 nm or more, the dispersion of the ITOF particles is not uniform, and when applied to the panel, the applicability deteriorates and the surface of the coated surface may be roughened, thereby making it difficult to apply uniformly.

The concentration of the conductive colloidal solution is 1 to 10 wt%.

When it is 1 wt% or less, when the film is formed, it is difficult to obtain sufficient conductivity due to the small amount of ITOF in the conductive layer. When the concentration is 10 wt% or more, the conductivity is good but the transmittance and the surface of the coating film may be deteriorated.

In the application using the colloidal solution, the ITOF conductive particles were first supplied to the surface of the panel through the evacuation process during the manufacturing process of the CRT, and then rotated at a rotational speed of 100 to 2000 rpm for about 1 hour at about 200 ° C. The heat treatment is performed to form a conductive film 14 coated with a thickness of about 500 to 10,000 kPa.

After the injection of the sol solution made of silicon oxide (SiO ₂ ) or silicon oxide-titanium oxide (SiO ₂ -TiO ₂ ) on the conductive film 14 thus formed, the coating was rotated at a rotational speed of 100 to 2000 rpm and then about 200 ° C. The low reflection film 15 is prepared by heat treatment at about 1 hour.

At this time, the coating thickness is about 70 to 100nm.

When the coating thickness is 70 nm or less or 100 nm or more, the reflectance of the low reflection film becomes 2% or more, so the effect of the low reflection film is inferior.

Another method of forming the film is indium oxide (In ₂ O ₃ ) doped with tin (Sn) and fluorine (F), that is, conductive film 14 by physical vapor deposition on the surface of the panel by sputtering using an ITOF sintered body. To produce a low reflection film using a colloidal solution containing silicon oxide or silicon oxide-titanium oxide (SiO ₂ -TiO ₂ ) particles, or a silicon sintered body of silicon oxide or silicon oxide-titanium oxide (SiO ₂ -TiO ₂ ) The low reflection film 15 is formed by physical vapor deposition on the panel surface by sputtering.

The following is described according to the embodiment.

Example 1

Indium oxide (In ₂ O ₃ ) doped with 5 wt% tin (Sn) and 8 wt% fluorine (F), that is, ITOF fine particles (average particle diameter 20 nm) and silicon oxide or silicon oxide-titanium oxide (SiO ₂ -TiO ₂ ) The conductive film 14 is coated on the surface of the panel to a thickness of 70 nm using a mixed colloidal solution containing 3 wt% of fine particles, and then the low reflective film 15 having a thickness of 95 nm on the panel surface is a colloidal solution containing silicon oxide fine particles. It was prepared by forming.

At this time, the coating conditions were prepared by spinning at 150 rpm and spin coating to form a film, drying at 80 ° C. for 20 minutes, and heat-treating at 200 ° C. for 1 hour.

Example 2

A 27 nm conductive film 14 was prepared by physical vapor deposition on a panel surface by sputtering using 5 wt% tin (Sn) and 8 wt% fluorine (F) doped indium oxide (In ₂ O ₃ ), that is, an ITOF sintered body. The low reflection film 15 was made using a colloidal solution containing silicon oxide or silicon oxide-titanium oxide (SiO ₂ -TiO ₂ ) particles.

Example 3

A 27 nm conductive film 14 was prepared by physical deposition on a panel surface by sputtering using 5 wt% tin (Sn) and 8 wt% fluorine (F) doped indium oxide (In ₂ O ₃ ), that is, an ITOF sintered body. And by using a silicon oxide or silicon oxide-titanium oxide (SiO ₂ -TiO ₂ ) ceramic sintered by physical deposition on the surface of the panel by the sputtering method to produce a low-reflection film 15 of 110nm.

Comparative Example 1

3 wt% of indium oxide (In ₂ O ₃ ) doped about 4 wt% of tin (Sn), that is, ITO particles (average particle diameter 20 nm) and silicon oxide-titanium oxide ((SiO ₂ -TiO ₂ ) particles It is prepared by coating the conductive film 14 on the surface of the panel using a mixed colloidal solution at a thickness of 70 nm, and then forming a 95 nm low reflection film 15 on the surface of the panel using a colloidal solution containing silicon oxide fine particles.

At this time, the coating conditions were prepared as in Example 1.

Comparative Example 2

Indium oxide (In ₂ O ₃ ) doped with 5 wt% of tin (Sn), i.e., ITO sintered body, was physically deposited on the panel surface by sputtering to prepare a conductive film 14 having a thickness of 27 nm, and containing silicon oxide fine particles. 95 nm of the low reflection film 15 was made and manufactured using the colloid solution.

After the CRT was manufactured using the panel according to the above Examples and Comparative Examples, the conductivity of each point shown in FIG. 5 was evaluated and shown in Table 1, and the reflectance and transmittance at 550 nm wavelength were measured. Indicated.

As can be seen, in the case of the present invention in which the conductive ITO contains fluorine, not only the conductivity of the conductive film is improved, but the reflectance is similar, but the transmittance is improved.

Comparison of Surface Electric Resistance Characteristics (Unit: Ω / □) Measuring point Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 #One 4.62 E + 04 2.26 E + 02 1.32 E + 02 4.62 E + 05 7.53 E + 3 #2 5.84 E + 04 4.68 E + 02 1.09 E + 02 5.73 E + 05 6.91 E + 3 # 3 6.18 E + 04 2.81 E + 02 3.98 E + 02 5.18 E + 05 5.43 E + 3 #4 5.23 E + 04 3.57 E + 02 1.07 E + 02 4.72 E + 05 4.36 E + 3 # 5 4.89 E + 04 4.42 E + 02 1.52 E + 02 4.28 E + 05 6.83 E + 3 # 6 5.67 E + 04 3.74 E + 02 1.01 E + 02 3.19 E + 05 6.31 E + 3 # 7 7.67 E + 04 5.79 E + 02 1.24 E + 02 5.42 E + 05 7.93 E + 3 #8 6.73 E + 04 3.68 E + 02 7.06 E + 02 4.65 E + 05 8.17 E + 3 # 9 6.79 E + 04 5.62 E + 02 2.47 E + 02 4.72 E + 05 9.26 E + 3

Comparison of transmittance characteristics (unit:%) Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Transmittance 54 57 56 50 52 reflectivity 0.5 0.1 0.2 0.5 0.2

As described above, the present invention forms a conductive film by adding fluorine (F) to the conventional indium oxide (In ₂ O ₃ ) doped with tin (Sn) and adjusting the mixing ratio thereof, and forming a low reflection film thereon. By forming, the image display surface of the cathode ray tube which not only improves conductivity but also improves transmittance is obtained.

Claims (6)

The conductive film and the low reflection film are sequentially formed on the outer surface of the panel showing the image display surface, wherein the conductive film is composed of tin (Sn), fluorine (F), and indium oxide (In ₂ O ₃ ). Color cathode ray tube with antireflection function. The method of claim 1, A colored cathode ray tube with a charge and antireflection function, wherein the conductive film is, by weight%, 1 to 10% tin (Sn), 1 to 30% fluorine (F), and the rest is indium oxide (In ₂ O ₃ ). The method of claim 1, The conductive film is a colored cathode ray tube with a charge and antireflection function, characterized in that the coating by using a colloidal solution containing tin, fluorine, indium oxide conductive particles. The method of claim 1, The conductive film is formed by sputtering a sintered body composed of tin, fluorine, indium oxide, the color cathode ray tube having antistatic and antireflection functions. The method of claim 1, The low reflection film is a color cathode ray tube with a charge and antireflection function, characterized in that by applying a colloidal solution containing silicon oxide or silicon oxide-titanium oxide (SiO ₂ -TiO ₂ ) particles. The method of claim 1, A low-reflection film is a color cathode ray tube with a charge and antireflection function, characterized in that formed by sputtering using a silicon oxide or silicon oxide-titanium oxide (SiO ₂ -TiO ₂ ) ceramic sintered body.

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