JP2002063852A - Front glass for plasma display panel, the plasma display panel and manufacturing method of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the front glass for a plasma display panel with improved contrast at lighted part, and to provide a plasma display panel and a manufacturing method of the same. SOLUTION: A front glass of the plasma display sealed by a front glass and a back side glass, made of a transparent glass, is characterized by the antireflection treatment applied on the surface of outer light incident side. The manufacturing method of the plasma display panel with the front glass for the plasma display panel is provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a front glass for a plasma display panel (hereinafter, also referred to simply as a front glass for a PDP) having an improved contrast in a bright place, and the P glass.
The present invention relates to a plasma display panel (PDP) having a front glass for DP and a method for manufacturing the same.

[0002]

2. Description of the Related Art PDP front glasses constituting PDPs are required to have improved visibility in bright places. Visibility in a light place can be improved by 1) reducing reflection of a light source such as a sun ray or illumination, and 2) improving contrast in a light place. Regarding the bright place contrast, it is required that the bright place contrast of an image displayed in the screen be as high as that of a CRT (CRT). Here, the bright place contrast (B _C0 ) is expressed by the following equation. B _C0 = (Ld + Lref) / (Lb + Lref) where Ld is the display emission luminance from the PDP, and Lb is P
The background light emission luminance from the DP, Lref, refers to the reflected light luminance of external light reflected on the front glass for PDP. Also,
External light is defined as P from the viewer in an environment where PDP images are viewed.
It is the light that goes to the front glass for DP. Note that the bright place contrast of a CRT is usually about 55, and that of a PDP is usually about 20. As a technique for increasing the light place contrast, an attempt has conventionally been made to use Tint (colored) glass, reduce the light transmittance of the front glass for PDP, and reduce the background light emission luminance Lb from the PDP. However, there is a problem that tint glass is difficult to melt and is inefficient, and that parallel production with transparent glass is inefficient.

[0003]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a P glass comprising a transparent glass substrate and having improved light place contrast.
An object of the present invention is to provide a front glass for DP, a PDP provided with the front glass, and a method for manufacturing the same. Another object of the present invention is to provide a front glass for a PDP, which is made of a transparent glass substrate and in which reflection of a light source such as sunlight or illumination is reduced.
And a PDP having the front glass and a method for manufacturing the same. Another object of the present invention is to provide a PDP comprising a transparent glass substrate, having improved light place contrast and reduced reflection of a light source such as sunlight or illumination.
To provide a front glass for use, a PDP provided with the front glass, and a method of manufacturing the same.

[0004]

According to the present invention, there are provided the following front glass for a plasma display panel 1) to 5), a method for manufacturing a plasma display panel 6), and a plasma display panel 7). The above object of the present invention is achieved. 1) In the front glass of the plasma display in which the front glass and the back glass are sealed, the front glass is made of a transparent glass substrate, and the surface on the side where external light is incident is subjected to an antireflection treatment. Features front glass for plasma display panels. 2) The front glass for a plasma display panel according to the above 1), wherein the antireflection treatment is performed by forming an optical interference film on a transparent glass substrate. 3) The front glass for a plasma display panel according to the above 1) or 2), wherein the antireflection treatment is performed by performing an antiglare treatment on the surface of the transparent glass substrate. 4) The front glass for a plasma display panel according to 1) above, wherein the antireflection treatment is performed by sticking a resin film subjected to antiglare treatment on a transparent glass substrate. 5) The front glass for a plasma display panel according to 1) above, wherein the antireflection treatment is performed by sticking a resin film having an optical interference film on a transparent glass substrate. 6) a step of providing device elements on a surface of the front glass for a plasma display panel according to any one of 1) to 5) opposite to the antireflection treated surface; and a step of providing device elements on the back glass. Sealing the front glass provided with the device elements and the back glass provided with the device elements. 7) A plasma display panel comprising the front glass for a plasma display panel according to any one of 1) to 5).

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION The front glass for PDP of the present invention comprises:
The anti-reflection treatment is performed on the outer surface of the transparent glass substrate. Here, the outer surface of the transparent glass substrate is the surface of the glass substrate on the side where external light is incident on the transparent glass substrate and the side where display light emission is emitted. The front glass is made of a transparent glass substrate, and the back glass is made of a transparent glass substrate or T
It consists of an int glass substrate. The transparent glass substrate preferably has a visible light transmittance of 75% or more, particularly preferably 85% or more. The front glass for PDP of the present invention is obtained by performing an antireflection treatment on the outer surface of a transparent glass substrate. Examples of such antireflection means include means using an optical interference film, specifically, providing an optical interference film made of an inorganic film on the outer surface of the transparent glass substrate. The optical interference film made of an inorganic film includes, for example, a light absorption type and a transparent type, and specifically, the following configurations can be preferably mentioned. a. Light absorption type (i) A structure in which a light absorption film and a low refractive index film are formed in this order on a substrate. (Ii) A structure in which a light-absorbing film, an oxidation barrier film (a film for preventing the light-absorbing film from being oxidized), and a low-refractive-index film are formed in this order on a substrate.

As the light absorbing film, it is preferable to use a material that substantially reduces the surface reflectance with respect to external light due to the light interference effect with the low refractive index layer formed thereon. This results in an excellent bright place contrast of the image of the front glass for PDP. Further, the light absorbing film is preferably conductive. By being conductive, it is preferable because the effect of preventing static electricity in the PDP and the leakage of electromagnetic waves from inside the PDP are prevented. As a light absorbing film satisfying such characteristics, at least one metal selected from the group consisting of gold, copper, titanium, zirconium, and hafnium, or a nitride of the metal (excluding gold) is used as a main component. And the like. Above all, those having a nitride of at least one metal selected from the group consisting of titanium, zirconium, and hafnium as a main component are preferable in view of the dispersion relationship between the refractive index and the extinction coefficient in the visible light region, and their optical constants Depending on the value of
There is a feature that a low-reflection region in a visible light region with respect to external light is widened by an optical interference effect with an upper low-refractive-index film. Further, a film mainly containing a nitride of at least one metal selected from the group consisting of titanium, zirconium, and hafnium is also preferable from the viewpoint of heat resistance, chemical resistance, and scratch resistance. Light absorbing film thickness (geometric thickness, the same applies hereinafter)
Is preferably 5 to 25 mm.

When two or more materials are used for the light absorbing film,
(1) It may be used as a composite material, or (2) it may be used by laminating films made of different materials so that the total thickness is preferably 5 to 25 nm. Further, the light absorption film containing titanium nitride as a main component has a value in the visible light region of an optical constant that is well matched with a low refractive index film (particularly, a silica film) to reduce the reflectance, and has a value of an absorption coefficient. Since the film thickness for obtaining an appropriate and moderate light absorptivity is in the range of several nm to several tens nm, it is particularly preferable in terms of productivity and reproducibility.

The low refractive index film has a refractive index of 1.3.
Membranes that are between 5 and 1.7 are preferred. As the low refractive index film, a film containing silica as a main component (particularly, a silica film) is preferable. The refractive index of the silica film is preferably from 1.46 to 1.52 (particularly preferably from 1.46 to 1.47), and the thickness of the silica film is preferably from 70 to 130 nm to reduce the low reflection wavelength range. This is preferable because it can be adjusted to the center of the visible light region. The silica film is preferably used also from the viewpoint of mechanical and chemical durability. The thickness of the silica film is more than 80 nm 12
It is particularly preferable that the thickness be 0 nm or less. If the silica film thickness is less than 80 nm, the reflectance on the long wavelength side tends to increase, and if it exceeds 120 nm, the rise of the reflectance on the short wavelength side tends to shift to the long wavelength side.

After forming a light absorbing film on the outer surface of a transparent glass substrate, the light absorbing film is oxidized when a silica film as a low refractive index film is formed, or in a post-heating treatment after the film formation. Desired characteristics may not be obtained because the light absorbing film is oxidized. Therefore, by inserting a layer (oxidation barrier layer) for preventing oxidation of the light absorption film between the light absorption film and the silica film, oxidation during film formation can be prevented,
Heat resistance can be improved. The oxidation barrier layer is a thin film formed to prevent oxidation of another layer formed thereunder, and has no optical significance.

As the oxidation barrier layer, various metal films and metal nitride films different from the material of the light absorbing film can be used. Its thickness is 20 nm so as not to impair the original antireflection performance.
It is desirable that: If the thickness of the oxidation barrier layer is less than 1 nm, the improvement in heat resistance becomes insufficient. Therefore, it is preferable to insert an oxidation barrier layer having a thickness of 1 to 20 nm because heat resistance can be effectively improved.

As described above, the oxidation barrier layer has no optical significance and is an optically unnecessary layer.
The insertion of this layer may degrade the antireflection performance against external light. In particular, when the oxidation barrier layer is light-absorbing (for example, light-absorbing silicon), the thickness of the oxidation barrier layer is preferably about 5 nm or less from the viewpoint of antireflection performance. When a transparent oxidation barrier layer is used, the allowable thickness varies depending on the refractive index of this layer. When a material having a refractive index of about 2.0 (for example, silicon nitride or aluminum nitride) is used, the allowable film thickness becomes the largest, and a barrier layer of up to about 20 nm is formed between the lower light absorbing film and the upper silica film layer. In between, it can be inserted while maintaining low reflection characteristics against external light.

The oxidation barrier layer contains, as a main component, at least one metal selected from the group consisting of chromium, molybdenum, tungsten, vanadium, niobium, tantalum, zinc, nickel, palladium, platinum, aluminum, indium, tin and silicon. When a film or a film containing these nitrides as a main component, or a film containing at least one metal of the group consisting of titanium, zirconium and hafnium as a main component is used, sufficient antioxidant performance is improved and excellent. It is preferable because the maintenance of the anti-reflection characteristics can be compatible. In particular, a film containing silicon as a main component or a film containing silicon nitride as a main component is excellent in oxidation barrier performance. In addition, when the upper silica film is formed by a sputtering method using a conductive Si target, the target is This is advantageous in terms of production because it is not necessary to increase the material.

Means for forming a surface treatment film (light absorbing film, low refractive index film or oxide barrier film) on the outer surface of the transparent glass substrate include sputtering, ion plating, vacuum deposition, and CVD. Can be used.
Among them, a sputtering method and a vacuum evaporation method, which can easily increase the area and easily correct the film thickness distribution, are preferable. In particular, it is preferable to use an in-line type sputtering method in which good film quality and uniformity of the film quality are easily obtained and productivity is excellent. In addition, a DC (direct current) magnetron type sputtering method, in which the size of the apparatus can be easily increased, is preferable in terms of productivity. A nitride film (light absorbing film) formed by a sputtering method shows good heat resistance even in a thin film.

In the case where a film mainly composed of a metal nitride is used as the light absorption film, if a film mainly composed of a nitride is used as the oxidation barrier layer, the light absorption film and the oxidation barrier layer are formed in the same gas atmosphere. Can be formed by sputtering. This is a great advantage when an actual film forming facility by sputtering is assumed. That is, when a so-called in-line type sputtering apparatus excellent in mass productivity is considered, the light absorbing film and the oxidation barrier layer can be formed in the same chamber (referred to as chamber A). Therefore, the chamber for gas separation only needs to be provided between the chamber A and the chamber for forming a silica film which is subsequently formed on the upper layer, which is extremely efficient.

In particular, when a film containing titanium nitride as a main component is used as the light absorbing film and silicon nitride is used as the oxidation barrier layer, the effect of improving the adhesion between the titanium nitride film and the outermost silica film can be obtained. .

B. Transparent type This type preferably has a three-layer structure of a medium refractive index film / high refractive index film / low refractive index film on a substrate. As the material of the medium refractive index film, SnO ₂ , SnO _x N _y (where x is 1.80), which is a medium refractive index material having a refractive index of 1.8 to 2.2.
And y is in the range of more than 0 and less than 0.13. _{), TiO 2, SnSi x O} y, Bi 2 O 3, WO 3, Z
nAl _x O _y and SnAl _x O _y are exemplified. As the material of the high refractive index film, a high refractive index material having a refractive index 2.1 to 2.5, TiO _2, ZrO _2, a configuration using a Ta ₂ O ₅ and the like are preferable. As the low refractive index film, those described above are preferably used. Specifically, the transparent type film configuration includes, for example, SnO ₂ , TiO ₂ ,
A configuration in which SiO ₂ is formed in this order on a transparent glass substrate outer surface, for _{example, SnO x N y, TiO 2} , S
There is a configuration in which iO ₂ is formed in this order, and the latter configuration is suitable for the method of manufacturing a PDP of the present invention because it has excellent heat resistance. The thickness configuration of this transparent type
The medium refractive index film is 75 to 115 nm, and the high refractive index film is 0 to 40.
It is preferable that the thickness of the low refractive index film is in the range of 75 to 115 nm. Also, as another film configuration of the transparent type,
A single-layered low-refractive-index film (a silica film having a refractive index of about 1.4 or a film made of silicone) may also be used.

Next, anti-glare processing as anti-reflection processing means will be described. The anti-glare treatment includes A) a treatment for forming irregularities on the outer surface of the transparent glass substrate, and B) a treatment for forming irregularities on the surface of the resin film described later. The process A) may be provided by a mold in the process of manufacturing the front glass, or may be provided by physical or chemical treatment after the front glass is manufactured. Sandblasting is exemplified as the former physical means, and etching is mentioned as the latter means. Specific examples of the etching treatment include treatment with a hydrofluoric acid aqueous solution. Further, the resin may be covered with a resin containing inorganic particles. As the inorganic particles, for example, an average particle diameter of 10
Alumina, silica, tin oxide, mica, titanium dioxide and the like having a thickness of 100 μm are exemplified. As the resin, acrylic resin, urethane resin, epoxy resin or the like for adhesion or coating is used. The size and distribution of such irregularities are appropriately adjusted, but are preferably 5 to 15% in terms of the haze ratio of the transmitted light through which the external light passes through the front glass. If it is less than 5%,
There is no effect of improving the bright place contrast, and if it exceeds 15%, it is difficult to ensure the sharpness of the displayed image.

[0018] Here, the haze ratio after the external light incident in the direction perpendicular to the front glass surface is transmitted through the front glass, an index showing the degree of diffusion in the direction other than the direction of straight, rectilinear transmitted light intensity T ₁ , And the total transmitted light intensity T ₀ (measured using an integrating sphere), the haze ratio is the haze ratio (%) =
It is expressed as (T ₀ −T ₁ ) / T ₀ .

The surface roughness Ra of the outer surface of the transparent glass substrate is
It is preferably at least 1 μm, more preferably at least 3 μm. By using an optical interference film having excellent heat resistance on the transparent glass substrate as described above, or by performing an anti-glare treatment, it is possible to perform an anti-reflection treatment on the front glass before assembling the PDP, and to prevent an anti-reflection after assembling the PDP. As compared with the case where the processing is performed, it is possible to avoid the risk of a decrease in yield due to the processing.

The antireflection treatment means in the present invention includes: 1) means for adhering an antiglare-treated resin film on the outer surface of a transparent glass substrate, and 2) a resin film having an optical interference film made of an inorganic film. There is a means for sticking on the outer surface of the glass substrate. The resin film used in the above 1) and 2) can support the above-mentioned inorganic film, and is not particularly limited as long as it is transparent. However, a polyester film (for example, a PET (polyethylene terephthalate) film), a polycarbonate film, Triacetate films and the like can be exemplified. The thickness is preferably about 20 to 200 μm. The unevenness due to the optical interference film made of the inorganic film or the anti-glare treatment can be provided on the resin film by the method described above. Thereafter, an optical interference film made of an inorganic film or an adhesive film having a release film on the surface opposite to the surface provided with the unevenness by the anti-glare treatment can be provided.
After the DP is manufactured, the release film can be peeled off and adhered on the outer surface of the transparent glass substrate. The front glass for a PDP of the present invention includes a laminated front glass and an optical interference film made of an inorganic film or a resin film having irregularities formed by anti-glare treatment. The resin film used in the above 1) and 2) is preferably a colored resin film from the viewpoint of contrast.

The front glass for PDP, which has been subjected to an anti-reflection treatment such as an anti-glare treatment or an optical interference film made of the inorganic film on the outer surface of the transparent glass substrate for PDP, has a known device element, for example, A transparent electrode, a bus electrode, a transparent dielectric, a sealing layer, an MgO layer, and the like are provided. Also,
The back glass combined with the front glass is provided with device elements such as data electrodes, white dielectrics, stripe barriers, phosphor layers, sealing layers, and the like. The present invention seals a device having a device element on a front glass and a rear glass provided with a device element in such a manner that both device elements face each other, and performs PDP through processes such as exhaust, gas sealing, and aging. Can be manufactured.

In the process of forming device elements on the front glass, the formation of the transparent dielectric layer and the sealing layer and the sealing between the front glass and the back glass are usually performed at a temperature of 500 to 600 ° C.
Done in Therefore, as the anti-reflection treatment on the outer surface of the transparent glass substrate, a method of forming an optical interference film made of a heat-resistant inorganic film on the outer surface of the transparent glass substrate or a method of performing anti-glare treatment on the outer surface of the transparent glass substrate is performed. Those that are done are suitable. In the present invention, the front glass for PDP is not provided, even if the device element is provided, provided that the antireflection treatment is performed on the outer surface of the transparent glass substrate. It may be. Further, the various antireflection treatments may be appropriately combined. For example, an anti-glare treatment and an optical interference film made of an inorganic film may be used in combination. Further, on the outer surface of the transparent glass substrate of the front glass for PDP, a conductive antireflection film (for example, an oxide film and a metal film such as Ag) are alternately formed in this order by (2n + 1) layers (n ≧ 1). Multilayer film etc.)
By attaching a sputter-coated film, PDP
It is also possible to prevent electromagnetic waves from coming.

[0023]

EXAMPLES The present invention will be described below in detail with reference to examples, but the scope of the present invention is not limited by the examples. Various data shown below were measured or calculated as follows. The visible light transmittance is the visible light transmittance of incident light at an incident angle of 0 °, and the film surface regular reflectance is the visible light regular reflectance (non-film surface side) for visible light at an incident angle of 15 ° from the antireflection-treated side. And the film surface diffuse reflectance is the visible light diffuse reflectance (non-film) for visible light at an incident angle of 5 degrees from the antireflection-treated side. (Reflectance not including surface-side reflectance but including diffuse reflection component)
Was measured according to JIS R3106. In addition, the film surface regular reflectance and the film surface diffuse reflectance are obtained by measuring the reflectance only from the surface subjected to the antireflection treatment, and the reflection on the surface not subjected to the antireflection treatment (the opposite surface). It excludes components. In the measurement, a fiber spectrometer (MCPD-3000 manufactured by Otsuka Electronics Co., Ltd.) was used for the visible light transmittance and the film surface regular reflectance. The film surface diffuse reflectance was measured using a spectrophotometer (UV-3100P manufactured by Shimadzu Corporation).
Using (C), the measurement was performed with the antireflection treated surface in close contact with the integrating sphere. When measuring the film surface regular reflectance and the film surface diffuse reflectance, a black magic (Mitsubishi Paint marking pen) was applied to the glass surface opposite to the anti-reflection treated surface.
To eliminate the reflection from the back surface (the glass surface on the opposite side of the anti-reflection treated surface). Ld (display light brightness)
Was applied from the side subjected to anti-reflection treatment (from the side of the filter when a front protective filter was provided) from an antireflection treatment side, and the screen luminance of white display was measured. L
b (background light) was measured by applying an illuminometer (manufactured by Suga Test Instruments Co., Ltd.) from the side on which antireflection treatment was performed (from the side of the filter when a front protective filter was provided) and measuring the screen luminance of black display in a dark room. Lref is obtained by (filter reflectance + (film surface regular reflectance × back plate reflectance ² ) × filter transmittance ² ) × external light [cd / m ² ]. In this embodiment, the back plate reflectance is 20%, the filter transmittance is 60%, and the filter reflectance is 2%. B
_C0 is obtained by (Ld + Lref) / (Lb + Lref). The total reflectance is obtained by (filter reflectance + film surface regular reflectance × filter transmittance ²⁾ .

(Manufacture of Front Glass for PDP) Example 1 Front glass for PDP provided with an optical interference film composed of a light-absorbing type inorganic film The front glass for PDP (material:
Glass, size: thickness 2.8mm 960mm × 560
A titanium nitride film (light absorbing film), a silicon nitride film (oxidation barrier layer), and a silica film (low-refractive index film) were sequentially formed on the outer surface of a transparent glass substrate (mm, visible light transmittance: 90%). Each film thickness was 5.0 nm (titanium nitride film), 5.0 nm (silicon nitride film), and 85.0 nm (silica film). The visible light transmittance of the front glass for PDP is 70%,
The film surface regular reflectance was 1%.

The actual film formation was performed as follows. Using an in-line sputtering apparatus, a metal titanium target for forming a titanium nitride film and a boron-doped silicon target for forming a silicon nitride film were set in a first vacuum chamber. Second
A boron-doped silicon target for forming a silica film was provided in the vacuum chamber. A clean substrate film is placed in the chamber with the long axis direction up and down (perpendicular to the direction of travel)
Then, the whole back pressure was evacuated to 2 × 10 ⁻³ Pa.

Next, a discharge gas is introduced into the first vacuum chamber.
Introducing a mixed gas of Lugon and nitrogen (nitrogen is 20% by volume)
And a discharge pressure of 4 × 10^-1Conductance to Pa
Set. Then, a negative DC voltage is applied to the titanium target.
(Power density is about 4.0W / cm ^Two) And apply
A tan film was formed. Then, in the same atmosphere,
-Negative DC voltage (power density is about 1.5 W / cm
^Two) Was applied to form a silicon nitride film. Nitrogen deposited
The analysis of the titanium oxide film by ESCA
At this time, Ti: N: O (atomic ratio) is 1.0: 0.95:
It was 0.05.

Next, the front glass is moved to a second vacuum chamber, and a mixed gas of argon and oxygen (about 30% by volume of oxygen) is introduced into the chamber evacuated to a high vacuum, and the pressure becomes 3 × 10 ^-1 Pa. The conductance was set to be as follows. Next, an AC power is applied to the silicon target (the power density is about 6.0 W).
/ Cm ² ) to form a silica film (refractive index n = 1.47).

Example 2 Front glass for PDP provided with an optical interference film made of a transparent type inorganic film. The same P as in Example 1 was obtained by sputtering according to Example 1.
SnO _x on the outer surface of the transparent glass substrate of the front glass for DP
N _y (where x is 1.80 and y is 0.13), TiO ₂ , and SiO ₂ were sequentially formed. Each film thickness is
93.0 nm (SnO _x N _y film), 15.0 nm (TiO
₂ film) and 93.3 nm (SiO ₂ film). Note that P
The visible light transmittance of the front glass for DP alone was 93%, and the film surface regular reflectance was 1%.

Example 3 PDP with anti-glare treatment
Front glass for PDP Using the same front glass for PDP as in Example 1, a front glass for PDP having a front glass subjected to antiglare treatment with a haze ratio of 5% and Ra: 2 μm by hydrofluoric acid etching was produced. The visible light transmittance of the front glass for PDP alone was 85%, the diffuse reflectance of the film surface was 6%, and the regular reflectance of the film surface was 1%.

Example 4 A resin film having an optical interference film made of an inorganic film, 93.0 n in the same manner as in Example 2 on a PET having a thickness of 80 μm.
m (SnO ₂ film), 15.0 nm (TiO ₂ film), 93.
3 nm (SiO ₂ film) was provided. Next, the release film on one side of a commercially available transparent adhesive film (AD-ROC, manufactured by PORA TECHNO) was peeled off, and the film was bonded to the opposite side of the above film via an adhesive layer while being lightly pressed with a rubber roll, to thereby form an optical interference film made of an inorganic film. A resin film having a film was produced.
The film alone had a visible light transmittance of 93% and a film surface regular reflectance of 2%.

Example 5 A resin film having an optical interference film composed of an inorganic film was coated on a urethane film having a thickness of 0.3 mm and dyed with a dye in the same manner as in Example 2 to 93.0 nm (SnO).
₂ ), 15.0 nm (TiO ₂ film), 93.3 nm (S
iO ₂ film). Next, in the same manner as in Example 4, a transparent pressure-sensitive adhesive film was adhered to produce a resin film having an inorganic film. The visible light transmittance of the film alone was 56%, and the film surface regular reflectance was 1.0%.

(Manufacture of PDP 1) A transparent electrode, a bus electrode, a transparent dielectric, a sealing layer, and an MgO layer were sequentially provided on the opposite side of the front glass for PDP of Examples 1 to 3. Then, the front glass and the rear glass provided with the device elements are heat-sealed and subjected to exhaust, gas sealing, and aging steps, so that each PD is
P was manufactured.

(Manufacture of PDP 2) A PDP was manufactured in the same manner as above except that a front glass for PDP without anti-reflection treatment was used instead of the front glass for PDP used in Manufacturing 1 of PDP. On the outer surface of the transparent glass substrate, a release film of a resin film having an optical interference film made of an inorganic film of Examples 4 and 5 was peeled off and adhered to obtain a PDP of the present invention. The optical properties of the obtained PDP are as shown in Table 1. In Comparative Example 1, no antireflection treatment was performed.

[0034]

[Table 1]

From the above table, it can be seen that the PDP that has been subjected to the anti-reflection treatment of the present invention has improved bright place contrast (B _C0 ) as compared with the PDP that has not been subjected to the anti-reflection treatment. B _C0
It is practically preferable that the absolute value thereof is 1 or more, particularly 5 or more, with respect to those not subjected to the antireflection treatment.

Examples 6 to 9, Comparative Example 2 A front protective filter was provided on the front of the PDPs of Examples 1 to 4 and Comparative Example 1 to produce various PDPs. The front protective filter consists of a clear glass plate printed with conductive ink containing silver and borosilicate frit as the main components around the entire periphery and baked at a high temperature. ZnO / Ag / ZnO / Ag / ZnO /
An Ag / ZnO multilayer film is provided, and a low-reflection coating is applied on one surface of the multilayer film to a thickness of 80 μm.
Is applied so that the low-reflection coat is exposed, and the surface of the clear glass plate opposite to the surface coated with the multilayer film is colored by kneading a dye with a thickness of 0.1 mm.
A film in which a low-reflection coat is applied to one surface of a 3 mm urethane resin film is attached so that the low-reflection coat is exposed. PDP with front protection filter
As for the method of assembling, the PDP housing is electrically connected to the silver ink printed portion of the front protection filter with a conductive gasket, so that an electromagnetic shielding structure that covers the PDP is provided. The characteristic of this front protective filter is visible light transmittance of 60.0
%, Visible light reflectivity 2.0%, film resistance 2.5Ω / □, transmission color is neutral, electromagnetic shielding characteristics are 30MHz ~ 1
-10 dB or more over GHz.

Table 2 shows the optical properties of the obtained PDPs.
As shown in FIG.

[0038]

[Table 2]

The provision of the front protection filter usually lowers the luminance. However, the configuration of Example 7 or Example 9 can improve the bright place contrast without lowering the luminance. Further, the anti-glare treatments of Examples 3 and 8 reduce the specular reflection component (reflection component having the same incident angle and reflection angle) from the panel due to the anti-glare treatment. Since the reflection is reduced (the overall regular reflectance is suppressed), the visibility is improved. From the above table, it can be seen that P having been subjected to the anti-reflection treatment of the present invention
It can be seen that the DP has improved visibility in bright places compared to the one without it.

[0040]

The front glass for a PDP of the present invention can be efficiently manufactured only by performing an antireflection treatment on the outer surface of the transparent glass substrate, and the bright place contrast of the PDP or the reflection of the light source can be easily improved. And improve the visibility of the PDP.

Continued on front page F-term (reference) 4G061 AA20 BA11 CD20 5C027 AA10 5C040 GA02 GA09 GH10 JA07 KB13 MA04

Claims (7)

[Claims] 1. A front glass in a plasma display in which a front glass and a back glass are sealed,
A front glass for a plasma display panel, wherein the front glass is made of a transparent glass substrate, and an antireflection treatment is applied to a surface on a side where external light is incident. 2. The front glass for a plasma display panel according to claim 1, wherein the anti-reflection treatment is performed by forming an optical interference film on a transparent glass substrate. 3. The front glass for a plasma display panel according to claim 1, wherein the antireflection treatment is performed by performing an antiglare treatment on a surface of the transparent glass substrate. 4. The front glass for a plasma display panel according to claim 1, wherein the antireflection treatment is performed by sticking a resin film subjected to an antiglare treatment on a transparent glass substrate. 5. The front glass for a plasma display panel according to claim 1, wherein the antireflection treatment is performed by sticking a resin film having an optical interference film on a transparent glass substrate. . 6. A step of providing a device element on a surface of the front glass for a plasma display panel according to any one of claims 1 to 5 opposite to an antireflection treated surface, and a step of providing a device element on a back glass. And a step of sealing the front glass provided with the device element and the back glass provided with the device element. 7. A plasma display panel comprising the front glass for a plasma display panel according to claim 1.