JP2000243271A - Metal film forming method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a phosphor screen forming method, capable of suppressing the occurrence of swelling and peeling off of a metal film formed on a phosphor screen and of suppressing the constriction of the metal film. SOLUTION: In this forming method of a phosphor screen having a metal thin film layer 4 on phosphor layers 3B, 3G, 3R, a resin film 5 with a metal thin film 4 formed on its one surface is so affixed on the phosphor layers 3B, 3G, 3R such that the metal thin film 4 side does not directly abut on the phosphor layers 3B, 3G, 3R, the resin film 5 is crimped to the phosphor layers 3B, 3G, 3R by pressing it by the use of a flat plate 6, and the resin film 5 is thermally decomposed and removed by heating it. Occurrence of swelling and peeling off of the metal thin film 4 can be suppressed by performing heat treatment, after pressurizing it with the flat plate 6.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a cathode ray tube (CR)
T) The present invention relates to a method for forming a phosphor screen of an image display device utilizing electron beam excitation and emission of a phosphor such as a field emission display (FED), and more particularly to a method of forming a phosphor screen of a display device having a metal deposition film on a phosphor layer. .

[0002]

2. Description of the Related Art In recent years, as information has been diversified and densified, image display apparatuses have been required to have higher performance, larger size and further improvement in image quality. On the other hand, image display devices utilizing light emission by electron beam excitation currently include cathode ray tubes (CRT), fluorescent display tubes (VFD), and field emission displays (FED).
Among them, CRTs and high-voltage FEDs, which can increase the electron acceleration voltage, prevent the phosphor film from being charged and effectively extract phosphor light to the display surface. In general, a metal vapor-deposited film is provided on a phosphor layer for the purpose of improving the image quality, and it is necessary to uniformly form a metal vapor-deposited film having few pinholes.

[0003] In particular, the FE which is a flat-type image display device
In the case of D, an electron beam having a high current density is irradiated on the phosphor to generate a highly reactive gas by this stimulus, so that the gas is prevented from diffusing into a vacuum vessel, and an electron source, a partition wall, etc. An effect of not contaminating other device components is also expected, and in this regard, it has become extremely important to reduce pinholes in the metal deposition film.

[0004] Conventionally, as a method of forming this metal deposition film,
Generally, a method is generally used in which an intermediate film made of a resin is once formed on the phosphor layer, whereby the unevenness of the phosphor layer is flattened, a metal is deposited, and finally, the resin intermediate layer is thermally decomposed and removed.

[0005] Practical methods for forming a resin intermediate layer can be roughly classified into the following two methods. The first method is described in, for example,
No. 91 discloses a method of forming a solvent-based lacquer film by spin coating. Specifically, an aqueous solution containing colloidal silica, a surfactant, etc. is applied on the phosphor screen, and firstly, the uneven portion of the phosphor layer is moistened, and then a resin containing polymethacrylate as a main component together with a plasticizer and toluene and xylene. Dissolved in a non-polar solvent such as
This is sprayed on a phosphor screen, o / w type droplets are placed on phosphor irregularities, stretched by spin coating, and then water and solvent components are dried and removed.

A second method is described, for example, in US Pat.
No. 390, a method of forming a resin intermediate layer by directly applying an aqueous emulsion of an acrylate resin copolymer on a phosphor screen and spin-coating the same.

[0007]

However, the first method described above involves the following problems in the process. First, since the solvent-based lacquer liquid is sprayed, the mist contaminates the surrounding atmosphere significantly, and unless the surroundings of the apparatus are cleaned sufficiently frequently, lacquer dust accumulated around the apparatus falls into the phosphor screen. Problems occur. This eventually becomes a huge pinhole in the metal deposition film, which causes a reduction in image quality and process yield.

The second problem is that spraying a mist using a solvent having a low flash point involves the danger of fire or the like and requires a large investment in a carbon dioxide fire extinguishing system.

The above-mentioned second method has the following problems. That is, if the thickness of the resin intermediate layer is not sufficiently obtained, there is a problem that smoothing, which is the original purpose, cannot be performed. Therefore, in this method, a long time or a plurality of times of thermal decomposition removal steps are required, or it is necessary to intentionally form small holes for outgassing, so that a metal deposited film with few pinholes cannot be obtained naturally. In addition, a problem that the metal vapor deposition film often swells (fire blisters) or breaks (stripping) due to gas generated during thermal decomposition removal is likely to occur.

[0010] Further, it is extremely difficult in terms of manufacturing technology to uniformly dry an aqueous system, it is not stable even with strictly controlled air-conditioning equipment and a large amount of energy, and often has a white uniformity due to factors such as seasonal variation. WU) deteriorates.

There is a common problem that the above two methods use a spin coating method. That is, there is a problem in that most of the coating liquid is discarded, and there is much waste of material. This not only contradicts the demands of the era, such as zero emission, but also causes the problem that a resin intermediate layer film is formed outside the display surface, which is not originally required, and a process of removing and cleaning it is required. are doing.

[0012] In addition, spin coating on a surface having irregularities such as a phosphor screen patterned in a dot shape or a stripe shape always requires a pattern edge portion and a smooth portion.
The unevenness of light and shade depending on the rotation direction occurs, and the image quality deteriorates to a considerable extent. Further, the above problem becomes more serious as the area of the substrate increases.

On the other hand, methods for avoiding these problems have been proposed. For example, Japanese Unexamined Patent Application Publication No.
In the publication, a phosphor layer is formed on a dry film placed on a glass substrate, and then heated and melted, and the phosphor layer is submerged in the film to flatten the unevenness of the phosphor screen before metal deposition. A method is disclosed.

However, in this method, the film thickness is required to be approximately equal to the film thickness of the phosphor layer (20 μm or more), and the amount of gas generated at the time of thermal decomposition removal becomes large. Problems such as blisters and peeling are exacerbated. In addition, the denseness of the metal deposition film naturally deteriorates.

In Japanese Patent Application Laid-Open No. H10-510092, a resin film having a thickness of 10 μm or less previously deposited with a metal is arranged on a wet phosphor screen such that the metal and the phosphor screen face each other or not. And a method for thermal decomposition removal.

However, in a similar study by the present inventors,
The heat shrinkage of the film always became a problem, and it was difficult to leave a satisfactory metal-deposited surface on the phosphor screen even in a very small area. In addition, when the metal deposition surface is exposed to water, for example, in the case of typically used Al, the oxidation reaction is accelerated, and there is a great possibility that a significant deterioration in function will occur.

Therefore, according to the method of forming the resin intermediate layer, which has been conventionally proposed, the phosphor screen which has a small number of pinholes and is uniform and provides a good white uniformity can be obtained with good yield.
Moreover, it has been difficult to form a large-area phosphor screen.

The present invention has been made to solve such a problem, and the metal film on the phosphor screen has blisters,
An object of the present invention is to provide a method for forming a phosphor screen in which occurrence of peeling is suppressed and contraction of a metal film is suppressed.

[0019]

The metal film forming method of the present invention is a method for forming a metal film on a phosphor layer, wherein the resin film has a metal film formed on one surface on the phosphor layer. Is bonded in a direction in which the metal film and the phosphor layer do not face each other, and the resin film is pressed against the phosphor layer by applying pressure and heat-treated, and the heat treatment removes the resin film by thermal decomposition. Then, the metal film is brought into close contact with the phosphor layer.

In one embodiment of the metal film forming method of the present invention, the temperature of the heat treatment is lower than 260 ° C.

In one embodiment of the method for forming a metal film according to the present invention,
The pressurizing pressure is 1 × 10 ^ThreePa or more 1 × 10
^FourIt is less than Pa.

In one embodiment of the method of forming a metal film according to the present invention, the pressing is performed using a flat plate.

In one embodiment of the method for forming a metal film according to the present invention, the pressure is applied to at least the surface of Teflon, glass,
This is performed using a pressing member having one selected from ceramics.

In one embodiment of the metal film forming method of the present invention, the flat plate is a Teflon plate, a Teflon-lined metal, a flat plate of glass, or a ceramic plate containing silicon nitride as a main component.

[0025]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Some embodiments of the present invention will be described below with reference to the drawings. First, the overall configuration of a display panel of an image display device having a phosphor screen on which a metal film is formed by the method according to the present invention will be described.

FIG. 5 is a perspective view showing a display panel.
A part of the panel is cut away to show the internal structure. In the figure, 1005 is a rear plate, 1006 is a side wall, 1007 is a face plate, and 1005-1.
007 forms an airtight container for maintaining the inside of the display panel in a vacuum. When assembling the airtight container, it is necessary to seal the joint of each member to maintain sufficient strength and airtightness, but, for example, apply frit glass to the joint, and in the air or in a nitrogen atmosphere,
Sealing was achieved by firing at 400 to 500 degrees Celsius for 10 minutes or more. A method of evacuating the inside of the airtight container to a vacuum will be described later.

The rear plate 1005 has a substrate 1001
Are fixed, but N × M surface conduction electron-emitting devices 1002 are formed on the substrate. (N and M are 2
The above positive integer is set as appropriate according to the target number of display pixels. For example, in a display device for displaying high-definition television, N = 3000, M =
It is desirable to set the number to 1000 or more. In this embodiment, N = 3072 and M = 1024. The N × M surface conduction electron-emitting devices are arranged in a simple matrix by M row-directional wirings 1003 and N column-directional wirings 1004. Here, a portion formed by the substrate 1001, the surface conduction electron-emitting device 1002, the row-direction wiring 1003, and the column-direction wiring 1004 is referred to as an electron source substrate.

A fluorescent film 1008 is formed on the lower surface of the face plate 1007. On the rear plate side surface of the fluorescent film 1008, a metal back 1009 known in the field of CRT is provided. The purpose of providing the metal back 1009 is to improve the light utilization rate by mirror-reflecting a part of the light emitted from the fluorescent film 1008, to protect the fluorescent film 1008 from the collision of negative ions, and to reduce the electron acceleration voltage. The function may be to function as an electrode for applying the voltage, or to function as a conductive path for the excited electrons of the fluorescent film 1008. The metal film forming method according to the present invention employs a metal back 1009 on such a fluorescent film 1008 (phosphor layer).
The present invention relates to a method for forming a (metal film).

Dx1 to Dxm, Dy1 to Dyn, and Hv are electric connection terminals having an airtight structure provided for electrically connecting the display panel to an electric circuit (not shown). Dx1 to Dxm are the row direction wirings 1003 of the electron source substrate,
Dy1 to Dyn are the column wiring 1004 of the electron source substrate and Hv
Is electrically connected to the metal back 1009 of the face plate.

FIG. 6 shows the structure of a planar surface conduction electron-emitting device. FIG. 6 is a plan view (FIG. 6 (a)) and a cross-sectional view (FIG. 6 (b)) for explaining the configuration of the planar surface conduction electron-emitting device. In the figure, 1101 is a substrate, 1102 and 1103 are device electrodes,
Reference numeral 1104 denotes a conductive thin film, 1105 denotes an electron emitting portion formed by an energization forming process, and 1113 denotes a thin film formed by an energization activation process. Device electrodes 1102, 11
By applying a predetermined voltage to the metal back 03 and applying a high voltage to the metal back 1009, electrons are emitted from the electron emitting portion 1105 and reach the metal back 1009.

Next, a method for forming a phosphor screen according to the present embodiment will be described with reference to FIG. FIG. 1 is a schematic cross-sectional view showing a method for forming a phosphor screen according to the present embodiment in the order of steps.

First, as shown in FIG. 1A, a blue phosphor layer 3B (for example, ZnS: Ag, Cl phosphor) patterned as a reflection layer in a dot or stripe pattern is formed on a glass substrate 1 serving as a face panel. Body: P22-G1 manufactured by Kasei Optonics Co., Ltd., green phosphor layer 3G (for example, Z
nS: Cu, Al phosphor: P22 manufactured by Kasei Optonics, Inc.
-GN4), the red phosphor layer 3R (for example, Y ₂ O ₂ S: E
u3 ⁺ phosphor: P22-RE2) manufactured by Kasei Optonics Co., Ltd. is formed by a slurry photolithography method or a screen printing method, and thereafter, the organic resin used in forming the reflective layer and the phosphor layer is thermally decomposed. And remove.

At this time, in consideration of the impact given to the phosphor, it is preferable to fire at a temperature of about 450 ° C. or less in a time as short as possible. In addition, by removing the unnecessary organic resin sufficiently at this point, the gas generated at the time of thermal decomposition removal of the film with the metal deposition film can be significantly reduced, and therefore, the metal deposition film with few pinholes Can be formed.

Next, as shown in FIG. 1B, a resin film 5 having a metal deposition surface formed later on one side is formed on the phosphor layers 3B, 3G, 3R. Specifically, for example, a metal-deposited surface is formed in advance on the resin film 5, and the metal-deposited surface is attached so as not to face the phosphor layers 3B, 3G, and 3R.

Thereafter, as shown in FIG. 1C, a flat plate 6 is placed on the metal deposition layer 4, and the flat plate 6 is pressed and heated using, for example, a jig as shown in FIG. As a result, the laminated film below the flat plate 6 is pressed and fused.

The flat plate 6 is used for heating and fusing the metal deposition layer 4.
It is necessary not to cause a chemical reaction with the phosphor layer.
It is necessary not to peel off the metal deposition layer 4 from B, 3G, 3R. Therefore, it is necessary that the flat plate 6 be a Teflon plate with extremely low chemical reactivity, a flat plate made of metal or glass whose surface is lined with Teflon, or a ceramic plate containing silicon nitride as a main component. It is.

If the pressure applied to the laminated film on the glass substrate 1 by the flat plate 6 during pressurization is less than 1 × 10 ³ Pa, the resin film 5 cannot be sufficiently fixed to the phosphor screen substrate. In addition, thermal shrinkage depending on the stretching direction occurs, and vertical wrinkles and cracks occur on the metal deposition surface, which is not preferable.
When the pressure is 1 × 10 ⁴ Pa or more, the glass substrate 1 is broken,
There is a problem that distortion occurs. Therefore,
The pressure applied to the substrate laminate is 1 × 10 ³ Pa or more and 1 × 1
0 ⁴ should be in the range of less than Pa.

The resin film 5 must be a thermoplastic film that can be sufficiently fused at a temperature of 260 ° C. or less, which is the upper limit of the heat resistance of the Teflon plate. The resin interlayer is
Although it is a substance that is finally decomposed by heating, it is desirable that the substance can be decomposed at a temperature as low as possible or as short as possible in order to reduce damage to the phosphors of the body layers 3B, 3G, and 3R. Examples of resins satisfying these conditions include methacrylic and cellulose resins. In addition, a resin having the above-described properties can be appropriately used.

As described above, by applying heat while the resin film 5 on which the metal deposition layer 4 is formed is pressed by the flat plate 6, it is possible to suppress the occurrence of vertical wrinkles and cracks on the metal deposition surface. Can be.

It is desirable that the thickness of the resin film 5 be as small as possible. Further, in order to ensure the thermal decomposition property, the thickness is desirably 20 μm or less. Therefore, the resin film used in the present invention has a thickness of 1 μm.
It is preferably from 0 μm to 20 μm.

On the other hand, the resin film 5 may contain a metal or a compound thereof that does not adversely affect the phosphor. For example, a commercial PMA-based film (HBC025 manufactured by Mitsubishi Rayon Co., Ltd.) having a thickness of 15 μm has a thickness of about 7 μm.
% Muscovite (KAl ₂ (AlSi ₃ O ₁₀ ) (OH) ₂ )
Although this film contains these inorganic substances, it has not only excellent handling workability but also a binding effect at the interface between the phosphor and Al at the time of thermal decomposition removal of the resin intermediate layer. The effect that no peeling occurs and a suitable metal vapor-deposited film can be obtained has also been confirmed, which is extremely practical.

Subsequently, the laminated film on the glass substrate 1 thus pressed is cooled to room temperature, and the pressing jig and the flat plate 6 are removed. Finally, the phosphor screen substrate is thermally decomposed and removed in an appropriate baking furnace to obtain a phosphor screen with a metal deposition film as shown in FIG. 1 (d).

As described above, according to the present embodiment, it is possible to prevent heat shrinkage of the resin film 5, which is the most problem when the resin film 5 is heated and fused to the phosphor screen,
A good resin intermediate layer with a metal evaporated film can be obtained on the phosphor screen.

Further, since the metal film is previously deposited on one side of the resin film, there is no need to expose the phosphor substrate to the deposition process.
Therefore, it is possible to reduce the impact on the phosphor.

For increasing the area of the glass substrate 1,
Since the resin film 5 having a uniform film thickness is used as the resin intermediate layer, the finally obtained metal vapor-deposited film can be formed extremely uniformly without unevenness, and is easily handled. Since the method according to the present embodiment is a much simpler process than the conventional method, it is also excellent in mass productivity. In addition, material waste can be reduced,
It is also advantageous in terms of cost.

[0046]

Hereinafter, the above embodiment will be described in more detail with reference to examples and reference examples.

(Example 1) A 2.8 mm thick blue plate glass was washed with a cleaning liquid roll brush and a disk brush.
After washing with pure water ultrasonic rinsing and drying, using a black pigment paste, the width is 0.10 mm in the vertical direction and the pitch is 0.29.
240 mm stripes, 0.30 m wide
A pattern having 720 stripes of m and a pitch of 0.65 mm was screen-printed to form a black reflective layer having an opening area of 0.30 mm × 0.19 mm as shown in FIG.

Next, using phosphor pastes of red, green and blue colors, as shown in FIG.
m, 240 stripes each in the order of red, green, and blue at a pitch of 0.8 mm, formed by screen printing,
Next, the substrate was baked at 450 ° C. for 4 hours (hours) to remove the resin contained in the paste by thermal decomposition and removed, and a diagonal screen size of 10 inches and an aspect ratio of 4:
3. A phosphor screen substrate having 720 × 240 dots was obtained.

On the other hand, a solution prepared by dissolving 3 parts by weight of butyl carbitol acetate (special grade reagent manufactured by Kanto Kagaku Kogyo Co., Ltd.) and 30 parts by weight of methyl ethyl acrylate copolymer (manufactured by Rohm and Haas Co .: Paraloid B72) as a plasticizer using toluene as a solvent. Was prepared, and this solution was applied on a Teflon plate placed on a spin coater to form a film having a thickness of 15 μm.

Further, after aluminum having a thickness of 1000 ° was deposited on the film, the film with the Al deposited film was peeled off from the Teflon plate. After laminating this film on the above-mentioned phosphor screen such that the metal surface side does not directly contact the phosphor screen, a Teflon plate of the same size as the glass substrate is further laminated thereon, and using a jig shown in FIG. This substrate laminate was pressed at a pressure of 5 × 10 ³ Pa. Subsequently, the substrate laminate is put into an annealing furnace with a pressing jig attached, heated from 80 ° C. to 260 ° C. at a rate of 1 ° C./min, and maintained at 260 ° C. for 40 minutes. Allow to cool.

After cooling, the pressing jig and the Teflon plate were removed from the substrate laminate, and the substrate was placed in a firing furnace.
Temperature to 370 ° C at a rate of 1 ° C / min.
After maintaining at 70 ° C. for 5 hours, the temperature is further increased at a rate of 1 ° C./min.
After the temperature was raised to 50 ° C and maintained at 450 ° C for 30 minutes,
Cooling was performed at a rate of 2.5 ° C./min.

The substrate thus obtained was placed on an optical microscope, and the four corners, the middle part, and the center part were observed under a microscope with transmitted light. The number of pinholes of 5 μm, 5 μm or more was counted. Table 1 shows the results. Table 1 shows that the metal-deposited surface in this example has no pinholes of 5 μm or more, and that the pinholes of 1 to 5 μm are almost uniformly distributed over each observation site. A deposited film is formed.

[0053]

[Table 1]

(Example 2) Film thickness 1 mainly composed of PMA
5 μm commercially available film (HBC02 manufactured by Mitsubishi Rayon Co., Ltd.)
5) Aluminum having a thickness of 1000 ° is deposited on the phosphor screen, and this film is laminated on the phosphor screen manufactured in the same manner as in Example 1 so that the metal face does not directly contact the phosphor screen.
Further, a Teflon plate of the same size as the glass substrate was laminated thereon, and the substrate laminate was pressed at a pressure of 2.0 × 10 ³ Pa using the jig shown in FIG.

Subsequently, the substrate laminate was put into an annealing furnace with a pressing jig attached, and the temperature was lowered from 80 ° C. to 1 ° C./m.
The temperature was raised to 260 ° C. at a rate of in, maintained at 260 ° C. for 40 minutes, and then allowed to cool naturally.

After cooling, the pressing jig and the Teflon plate were removed from the substrate laminate, and the substrate was placed in a firing furnace.
Temperature to 370 ° C at a rate of 1 ° C / min.
After maintaining at 70 ° C. for 5 hours, the temperature is further increased at a rate of 1 ° C./min.
After the temperature was raised to 50 ° C and maintained at 450 ° C for 30 minutes,
Cooling was performed at a rate of 2.5 ° C./min.

The substrate thus obtained was placed on an optical microscope, and the four corners, the middle part, and the center part were observed under a microscope with transmitted light. The number of pinholes of 5 μm, 5 μm or more was counted. Table 1 shows the results. Table 1 shows that the metal-deposited surface in this example has no pinholes of 5 μm or more, and that the pinholes of 1 to 5 μm are almost uniformly distributed over each observation site. A deposited film is formed.

(Reference Example 1) A phosphor screen substrate manufactured by the same method as in Example 1 was placed on a spin coater, and colloidal silica (Snowtex ST-40, manufactured by Nissan Chemical Industries, Ltd.) was placed in pure water. Was dissolved in 5 parts by weight, and a solution adjusted to pH 4.7 using acetic anhydride was applied while rotating the substrate at a rotation speed of 300 rpm.

Subsequently, toluene was used as a solvent, and methyl ethyl acrylate copolymer (manufactured by Rohm and Haas:
A lacquer solution prepared by dissolving 15 parts by weight of paraloid B72) and 3 parts by weight of butyl carbitol acetate (special grade reagent manufactured by Kanto Kagaku Kogyo Co., Ltd.) was rotated at 120 rpm to rotate the substrate at about 1 so that the entire surface was uniform. The substrate was sprayed with a hot air at 95 ° C. at a wind speed of 15 m / s for 100 seconds and dried.

The film thickness when a lacquer was coated on a glass substrate under the same conditions was measured by a stylus thickness gauge to be about 1.8 μm. Thereafter, a film thickness of 1000 is formed on the phosphor screen.
ア ル ミ ニ ウ ム aluminum is vapor-deposited, and finally this substrate is carried into a firing furnace, heated to 450 ° C. at a rate of 1 ° C./min, maintained at this temperature for 30 minutes, and then −2.5 ° C. /
The resin intermediate layer was thermally decomposed and removed at a speed of min.

The substrate thus obtained was placed on an optical microscope, and the four corners, the middle part, and the center part were observed with transmitted light under a microscope. The number of pinholes of 5 μm, 5 μm or more was counted. Table 1 shows the results. From Table 1, the number of pinholes on the metal-deposited surface in this reference example is slightly larger.
And it turns out that the number is particularly large in the four corners,
It can be seen that the metal deposited film is non-uniform and white uniformity is poor compared to Example 1.

Reference Example 2 A phosphor screen substrate manufactured in the same manner as in Example 1 was placed on a spin coater, and a surfactant (trade name: Triton X-405, manufactured by Rohm and Haas Company) was placed in pure water. Was dissolved in 1 part by weight of
The coating was performed while rotating the substrate at a rotation speed of rpm.

Then, an acrylic emulsion (Primal B-74, manufactured by Rohm and Haas Company) in pure water 25
Parts by weight, 1 part by weight of butyl carbitol (manufactured by Kanto Chemical Industry Co., Ltd .: reagent grade), urethane block copolymer solution (manufactured by Rohm and Haas Co., Ltd .: product name Primal RM-8)
A solution prepared by dissolving 0.5 part by weight of W) and then adjusting the pH to 7.5 with aqueous ammonia was applied on the substrate at a rotation speed of 50 rpm, and the substrate was further rotated at a rotation speed of 300 rpm. . After that, the substrate is loaded into the dryer and
It was dried under the condition of 2 ° C. for 2 hours.

When the acrylic emulsion was coated on the glass substrate under the same conditions, the film thickness was measured to be about 5.8 μm using a stylus thickness gauge. After that, 1000 ° of aluminum is vapor-deposited on the phosphor screen, and finally, the substrate is carried into a firing furnace, heated up to 450 ° C. at a rate of 1 ° C./min, and maintained at this temperature for 30 minutes. ,
The resin intermediate layer was cooled at a heating rate of −2.5 ° C./min and thermally decomposed and removed.

The substrate thus obtained was placed on an optical microscope, and the four corners, the middle part, and the center part were observed under a microscope with transmitted light. The number of pinholes of 5 μm, 5 μm or more was counted. From Table 1, the metal-deposited surface in the present reference example has a large number of large pinholes, particularly 5 μm or more, has a non-uniform distribution of pinholes, lacks a symmetric shape on the screen, and has poor white uniformity. It can be seen that this is a non-uniform metal deposited film.

As described above, when the substrate laminate is not pressed using the pressing jig, the pinholes are formed with an uneven distribution after the resin intermediate layer is thermally decomposed and removed.
This has been demonstrated by the above-described Examples and Reference Examples.

[0067]

According to the present invention, it is possible to uniformly deposit a metal deposited film having few pinholes on a phosphor without unevenness. Therefore, it is possible to manufacture an image display device excellent in white uniformity even for a large screen, and it is possible to particularly contribute to the practical use of a wall-mounted television of the FED system.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing a phosphor screen forming method according to an embodiment of the present invention in the order of steps.

FIG. 2 is a schematic cross-sectional view showing a state where a substrate stack is pressed by a pressing jig in the phosphor screen forming method according to one embodiment of the present invention.

FIG. 3 is a plan view showing a pattern of a black reflective layer of a phosphor screen substrate used in Examples and Reference Examples in one embodiment of the present invention.

FIG. 4 is a plan view showing a pattern of a phosphor layer of a phosphor screen substrate used in Examples and Reference Examples in one embodiment of the present invention.

FIG. 5 is a schematic diagram showing an overall configuration of a display panel according to one embodiment of the present invention.

FIG. 6 is a schematic diagram showing a configuration of an electron-emitting device according to one embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Glass substrate 3B, 3G, 3R Phosphor layer 4 Metal deposition surface 5 Resin film 6 Flat plate

Claims (5)

[Claims] 1. A method for forming a metal film on a phosphor layer, comprising: forming a resin film having a metal film formed on one surface of the phosphor layer so that the metal film and the phosphor layer do not face each other. The resin film is pressed against the phosphor layer by applying pressure, and heat treatment is performed on the resin film, and the resin film is thermally decomposed and removed by the heat treatment.
A method for forming a metal film, comprising: adhering the metal film on the phosphor layer. 2. The method according to claim 1, wherein the temperature of the heat treatment is lower than 260 ° C. 3. The metal film forming method according to claim 1, wherein the pressure is 1 × 10 ³ Pa or more and less than 1 × 10 ⁴ Pa. 4. The method according to claim 1, wherein the pressing is performed using a flat plate. 5. The pressure is applied to at least a surface of Teflon,
The method according to any one of claims 1 to 4, wherein the method is performed using a pressing member having one selected from glass and ceramic.