JP2007335363A - Image display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image display device in which a sealing of a vacuum panel composed of a rear substrate, a front substrate and a supporting body can be realized in a low temperature and selection freedom of an electron source material, an electrode wiring material or the like can be widened. <P>SOLUTION: The image display device is composed of a front substrate 1 inside which a cathode and a phosphor is provided and a rear substrate 2 inside which a plurality of anode wirings and a plurality of electron sources each formed on the anode wirings respectively and which is arranged facing the frond substrate with a predetermined distance, a frame shaped supporting body 3 interposed around a display area between the front substrate 1 and the rear substrate 2 to keep a predetermined distance, and a sealing member to airtightly seal both end faces of the supporting body 3 and the front substrate 1 and the rear substrate 2. The sealing member of vacuum side of a vacuum container is composed of a siloxane compound sealing member 10b having at least a phenyl group and that of an atmosphere side of the vacuum container is composed of a low melting point sealing member 10a and a hybrid sealing structure at a relatively low temperature can be realized. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an image display device using electron emission into a vacuum formed between a front substrate and a back substrate, and more particularly to a hybrid sealing structure of a support that holds and fixes the two substrates at a predetermined interval. Is.

  Conventionally, color cathode ray tubes have been widely used as display devices with excellent brightness and high definition. However, with the recent increase in image quality of information processing devices and television broadcasting, there is an increasing demand for flat panel displays (panel displays) that have high luminance and high definition characteristics and can be reduced in weight and thickness. .

  As typical examples, liquid crystal display devices, plasma display devices and the like have been put into practical use. In particular, an image display device using electron emission from an electron source into a vacuum (hereinafter referred to as an electron emission display device or a field emission display device; hereinafter referred to as an FED), which can achieve high brightness, Various types of panel display devices such as an organic EL display characterized by low power consumption have been put into practical use.

  Among such panel type display devices, the field emission type display devices include those having an electron emission structure proposed by CASpindt et al., Those having a metal-insulator-metal (MIM) type electron emission structure, Known are those that have an electron emission structure (also called a surface conduction electron source) that uses the electron emission phenomenon due to the quantum tunnel effect, and those that use the electron emission phenomenon of diamond films, graphite films, and carbon nanotubes. It has been.

  Of such panel type display devices, the field emission image display device includes a back substrate having a cathode wiring having a field emission type electron source and a control electrode formed on the inner surface, and an inner surface facing the rear substrate. The front substrate on which the anode and the phosphor are formed is bonded to the inner peripheral edge of both substrates through a support frame and hermetically sealed to form a panel, and the sealed space of the panel is set to a pressure lower than the atmospheric pressure or a vacuum state. Held and configured. The control electrode is disposed so as to intersect the cathode wiring with an insulating layer or an insulating gap from the cathode wiring.

  The control electrode has one or more apertures for each pixel that allow electrons from the electron source on the cathode wiring to pass therethrough. Further, a spacing member is interposed between the back substrate and the front substrate in order to keep the spacing between the back substrate and the front substrate at a predetermined value. The spacing member is formed of, for example, a thin plate of glass or ceramics, and is planted at a position avoiding the pixels.

  FIG. 9 is a cross-sectional view of an essential part for explaining the configuration of an image display device as a conventional panel type display device of this type. In this image display device, an image is formed by irradiation of an electron beam emitted from the back substrate 2 on which the plurality of electron emitters 5 are mounted, the back substrate 2 facing the back substrate 2 and being emitted from the electron emitters 5. A front substrate 1 on which an image forming member 6 is mounted; a frame-like support 3 between the rear substrate 2 and the front substrate 1 that supports the peripheral portion of the rear substrate 2 and the front substrate 1; and the front substrate 1 and the rear substrate 2 and a spacer (interval holding member) 4 disposed as a support post.

  The image display device configured as described above has a frame-shaped glass member having a substantially rectangular cross section at the peripheral edge between the front substrate 1 and the back substrate 2 as shown in FIG. The support 3 formed by assembling is bonded and fixed to both end faces by sealing members 10a and 10b made of, for example, frit glass material, and a spacer 4 made of a glass member is provided at both ends of the peripheral edge. The surface is bonded and fixed with a fixing member 8 made of, for example, a frit glass material interposed. This improves the atmospheric pressure resistance and impact resistance. This type of image display apparatus is disclosed in, for example, Patent Document 1 below.

Japanese Patent No. 3241219 (Japanese Patent Laid-Open No. 7-230776)

  In the image display device described in Patent Document 1, a frit glass material is generally used as a sealing member that hermetically seals both end surfaces of a support 3 between a front substrate 1 and a back substrate 2. Yes. The frit glass material is melt-sealed at about 450 ° C. and then evacuated at a temperature below the softening point of the frit glass, for example, about 300 ° C. to 400 ° C. Therefore, for example, in an electron emission structure using an MIM type electron source as the electron emission element 5, heat resistance of about 450 ° C. or more is required. There is a problem that it is difficult to select an electron source material and an electrode wiring material for the purpose of improving electrical characteristics under such temperature constraints.

  Accordingly, the present invention has been made to solve the above-described conventional problems, and an object thereof is to realize sealing of a vacuum vessel composed of a back substrate, a front substrate, and a support at a low temperature. Accordingly, an object of the present invention is to provide an image display device capable of expanding the selectivity of an electron source material, an electrode wiring material, and the like.

  In order to achieve such an object, the image display device according to the present invention has a sealing member that hermetically seals the inner peripheral edge portions of the front substrate and the rear substrate and both end surfaces of the support at least on the vacuum side of the vacuum vessel. By including a siloxane compound sealing member having a group and including a low-melting point sealing member on the atmosphere side of the vacuum vessel, it becomes possible to seal at a relatively low temperature, thereby solving the problems of the background art Can do.

  The image display device according to the present invention preferably has phenyl heptamethylcyclotetrasiloxane and 2,6-cis-diphenylhexamethylcyclotetrasiloxane as the siloxane compound sealing member having a phenyl group in the above configuration. It is characterized by using a silicon resin containing.

  The image display device according to the present invention is preferably characterized in that, in the above configuration, the siloxane compound sealing member having a phenyl group is thermally cured at a temperature of 200 ° C. to 300 ° C.

  The image display device according to the present invention is preferably characterized in that, in the above configuration, a low melting point frit glass that is thermally cured at a temperature of 300 ° C. to 380 ° C. is used as the low melting point sealing member.

  It should be noted that the present invention is not limited to the configurations described in the above-described configurations and the embodiments described later, and it goes without saying that various modifications can be made without departing from the technical idea of the present invention. .

  According to the present invention, the sealing member is sealed by sealing the high vacuum side of the vacuum container with a siloxane compound sealing member having at least a phenyl group, and sealing the atmosphere side of the vacuum container with a low melting point sealing member. Since sealing at temperature and hermetic holding sealing can be realized at the same time, selectivity and quality stability of electron source materials and electrode wiring materials can be improved, electrical characteristics can be improved, and manufacturing energy can be improved. It is possible to obtain extremely excellent effects such as reduction of the amount.

  Hereinafter, specific embodiments of the present invention will be described in detail with reference to the drawings of the examples.

  FIG. 1 is a plan view of a principal part for explaining a schematic configuration of a field emission display device according to a first embodiment of an image display apparatus according to the present invention, and FIG. 2 is a principal part cut along the line AA ′ of FIG. It is an expanded sectional view. 1 and 2, reference numeral 1 is a front substrate made of a translucent glass plate, and reference numeral 2 is a rear substrate made of a translucent glass or a ceramic material such as alumina in the same manner as the front substrate 1. The front substrate 1 and the rear substrate 2 are formed with a thickness of about 3 mm, for example.

  Reference numeral 3 is a support that also serves as an outer frame that is formed by cutting a molded body such as a glass plate or a frit glass plate into a rod shape, and bonding and fixing it in a frame shape. The inner peripheral edge between the front substrate 1 and the rear substrate 2 is installed by being bonded and fixed by two kinds of sealing members 10a and 10b described later, and the distance between the front substrate 1 and the rear substrate 2 is set to a predetermined dimension. For example, it is held at about 3 mm. Further, the front substrate 1 and the rear substrate 2 and both end surfaces of the support are joined by the two kinds of sealing members 10a and 10b and hermetically sealed to constitute a vacuum container.

  Further, reference numeral 4 shown in FIG. 2 is a plate-like spacer as a spacing member, and this spacer 4 is a thin glass plate of about 0.1 mm or less or a ceramic plate material such as alumina having a width of about 3 mm. (Height dimension) is formed by cutting, extending in one direction (X direction) substantially perpendicular to the substrate surface of the front substrate 1 and the rear substrate 2, and arranging a plurality of sheets in parallel in the other direction (Y direction) It is fixedly arranged by fixing members 11a and 11b, which will be described later, and the distance between the front substrate 1 and the rear substrate 2 is maintained at a predetermined dimension in cooperation with the support 3.

  Reference numeral 5 denotes an electron-emitting device. The electron-emitting device 5 includes a cathode wiring 51, an electron source 52, and a control electrode 53 as shown in an enlarged cross-sectional view of the main part in FIG. They are arranged on the substrate 2 at a predetermined interval. A plurality of the cathode wirings 51 extend in one direction (X direction) on the inner surface of the back substrate 2 and are arranged in parallel in the other direction (Y direction).

  The end portion of the cathode wiring 51 is divided into two sides of the back substrate 2 as a cathode wiring lead line 51a and is drawn to the outside of the hermetic seal portion. The cathode wiring 51 is formed by, for example, a vapor deposition method, or a thick paste is used to print a silver paste in which conductive silver particles having a particle size of about 1 μm to 5 μm are mixed with a low-melting glass that expresses insulation, for example, It is formed by heating and baking at a temperature of about 600 ° C.

  The control electrode 53 is disposed above the cathode wiring 51 so as to be insulated from the cathode wiring 51, and an end portion of the control electrode 53 serves as a control electrode lead-out line 53a on the other side of the rear substrate 2 and is hermetically sealed. It is pulled out outside.

  Further, an electron source 52 arranged at a predetermined interval on the cathode wiring 51 is a metal-insulator-metal (MIM) type electron-emitting device, and an electron-emitting structure (surface) utilizing an electron-emitting phenomenon due to a quantum tunnel effect. (Also referred to as a conduction electron source), a diamond film, a graphite film, or a carbon nanotube. As this formation method, for example, a method of printing a carbon nanotube paste on the surface of the cathode wiring 51 which has been printed and fired with a thick film, and heated and fired at a temperature of about 590 ° C. in a vacuum, for example, is used.

  Reference numeral 6 denotes an image forming member. The image forming member 6 includes a phosphor film 61, a metal back film 62 deposited on the phosphor film 61, and a black matrix (BM) film 63. Formed and disposed on the inner surface of the front substrate 1.

Reference numeral 10a denotes an inner peripheral edge of the front substrate 1 and the rear substrate 2, and an outer peripheral edge of the upper and lower end surfaces of the support 3, that is, a peripheral edge in contact with the atmosphere side, as shown in an enlarged cross-sectional view of the main part in FIG. The low melting point sealing member 10a is formed of, for example, crystallized frit glass mainly composed of PbO, B ₂ O ₃ and ZnO.

  Reference numeral 10b denotes a siloxane compound having a phenyl group that seals the inner peripheral edge portions of the front substrate 1 and the rear substrate 2 and the inner peripheral edge portions of the upper and lower end surfaces of the support 3, that is, the peripheral edge portion in contact with the high vacuum side. The siloxane compound sealing member 10b which is a sealing member and has a phenyl group is formed of a silicon resin containing, for example, phenylheptamethylcyclotetrasiloxane and 2,6-cis-diphenylhexamethylcyclotetrasiloxane. . The seal thickness T of the low melting point sealing member 10a and the siloxane compound sealing member 10b is about 20 μm as shown in FIG.

  This siloxane compound sealing member 10b having a phenyl group is obtained by dissolving phenylheptamethylcyclotetrasiloxane and 2,6-cis-diphenylhexamethylcyclotetrasiloxane in an organic solvent such as toluene, xylene, or solvent naphtha, and is about 100 ° C. A paste-like adhesive can be formed by heating at ˜150 ° C. for about 2 hours to 5 hours, causing the condensation reaction while evaporating the solvent, and adjusting the viscosity of the reaction product to about 100 cps to 1000 cps.

The paste-like adhesive thus obtained is applied to the inside (high vacuum side) of the upper and lower end surfaces of the support 3 with, for example, a dispenser, and further PbO and the outside of the upper and lower end surfaces of the support 3 (atmosphere side). A low melting point frit glass material mainly composed of B ₂ O ₃ and ZnO is applied by, for example, a dispenser, and then placed in a vacuum chamber and evacuated while being heated to about 100 ° C. in a reduced pressure of about 100 Pa. The solvent is evaporated and degassed, and once taken out to the atmosphere.

  Next, the front substrate 1 and the back substrate 2 to be bonded are superposed on the portions of the upper and lower end surfaces of the support 3 to which the adhesive material is applied, and are pressure-bonded while applying a load from the outer surface (Z direction in FIG. 1). The airtight joining is performed by the siloxane compound sealing member 10b that has been heated to about 200 ° C. to 300 ° C. to cure the paste adhesive.

  Next, evacuation is performed at about 370 ° C. while melting the low melting point frit glass material in a nitrogen atmosphere heated to a temperature of about 300 ° C. to 350 ° C., and after reaching a predetermined degree of vacuum, Airtight joining is performed by the low melting point sealing member 10a that is cured by heating and baking at 380 ° C.

  In the above-described embodiment, the sealing method of the siloxane compound sealing member 10b has been described in detail. The sealing method of the low melting point sealing member 10a is a siloxane compound sealing member made of a frit glass material by a known coating method. It is also possible to form the hermetic joint between the low-melting point sealing member 10a and the siloxane compound sealing member 10b in the same process by performing a series of heat treatment processes in parallel with the coating process 10b.

  These sealing members 10a and 10b have a front substrate 1 and a rear substrate 2 arranged on the upper and lower end surfaces of the support 3, respectively, and the peripheral portions of the front substrate 1 and the rear substrate 2 stacked in the Z direction are hermetically sealed. Worn. A portion surrounded by the support 3 and the front substrate 1 and the rear substrate 2 constitutes the image display region 12 shown in FIG. 1, and the inside of the display region 12 is maintained in a vacuum state. .

Reference numerals 11a and 11b are fixing members for bonding and fixing the spacer 4 to the front substrate 1 and the rear substrate 2, respectively. The fixing member 11a is formed of, for example, crystallized frit glass mainly containing B ₂ O ₃ , PbO, and ZnO as a substance having hysteresis characteristics, and the back substrate 2 and the lower end surface 42 of the spacer 4 are bonded and fixed. ing.

The fixing member 11b is formed of amorphous frit glass mainly composed of SiO ₂ , B ₂ O ₃ and PbO, for example, and the front substrate 1 and the upper end surface 41 of the spacer 4 are bonded and fixed. Of these fixing members 11a and 11b, the fixing member 11b is formed of amorphous frit glass or the like having a hardness substantially equal to or lower than the hardness of the spacer 4.

  In such a configuration, electrons radiated from the electron source 52 arranged on the cathode wiring 51 are controlled by the electron passage holes of the control electrode 53 to which a grit voltage of about 100 V is applied. Passes through the image forming member to which an anode voltage of several KV to 10 KV is applied, passes through the metal back layer (anode) 62, and strikes the phosphor layer 61 to cause the phosphor 61 to emit light. A desired display is configured on the viewing surface. Unit pixels are formed in a matrix at intersections between the cathode wiring 51 and the control electrode 53, and a display region is formed by the pixels arranged in the matrix. Generally, a color pixel composed of red (R), green (G), and blue (B) is formed by three groups of unit pixels.

  In the image display device configured as described above, the siloxane compound sealing member 10b having a phenyl group is about 300 on the high vacuum side of the vacuum container constituted by the assembly of the front substrate 1, the rear substrate 2, and the support 3. Heat-cured at a temperature of ℃ or less and firmly bonded and fixed and bonded. On the atmosphere side of the vacuum vessel, the low-melting-point sealing member 10a is heat-cured at a temperature of about 380 ℃ and firmly bonded and fixed and bonded. Therefore, hermetic sealing and hermetic maintenance sealing at a low temperature below the melting point (about 430 ° C.) of the glass can be obtained at the same time.

  Since the siloxane compound sealing member 10b is cured at about 300 ° C. and is firmly bonded and fixed, the low melting point frit glass is melted to the heating and firing temperature (about 400 ° C.) of the low melting point sealing member 10a. However, the siloxane compound sealing member 10b is firmly cured and bonded without causing a shape change.

  As a result, a series of gas that has been melt-sealed at about 400 ° C. by using a frit glass material and evacuated at a temperature below the softening point of the frit glass material (for example, about 400 ° C. or less). Compared to the sealing process and the evacuation process, it is not exposed for a long time at a high temperature, so that the promotion of oxidation of the electron source material and the electrode material can be prevented.

  In addition, the siloxane compound sealing member 10b having a phenyl group is processed into a sheet-like adhesive by heat-treating a paste-like adhesive, and is superposed on inner edge portions of both end faces of the support 3 under the same temperature conditions as described above. Even if it is sealed, a similar sealing structure can be realized. By using a sheet-like adhesive as the siloxane compound sealing member 10b, there is little degassing during the defoaming treatment, and the heat resistance is excellent.

  In addition, the image display device configured as described above can be formed at a relatively low temperature of about 400 ° C. or less because the hybrid sealing of the front substrate 1 and the rear substrate 2 and the support can be performed at a relatively low temperature. It becomes possible to reduce energy. In addition, since sealing can be performed at a relatively low temperature, it is possible to select an electron source material, an electrode wiring material, and the like that can withstand the temperature conditions at the time of vacuum sealing, thereby improving quality stability. In addition, the electrical characteristics can be improved.

  FIG. 5 is a cross-sectional view of an essential part showing the structure of a support sealing structure for explaining an image display device according to a second embodiment of the present invention. Is omitted. 5 is different from FIG. 4 in that the inner peripheral edge portions of the front substrate 1 and the rear substrate 2 and the upper and lower end surfaces of the support 3 are sealed with a siloxane compound sealing member 10b, and the atmosphere of the siloxane compound sealing member 10b. It is sealed by the low melting point sealing member 10a at the outermost surface in contact with the surface.

  In such a configuration, a sealing structure in which the low-melting-point sealing member 10a serves as a barrier layer as an airtight holding of the siloxane compound sealing member 10b is obtained, so that the same effect as in the first embodiment can be obtained.

  FIG. 6 is a plan view of the main part as seen from the inner surface side of the rear substrate constituting the image display device according to the present invention. In FIG. 6, the main surface (front surface) of the back substrate 1 that is preferably made of glass or a ceramic material has a second direction that extends in the first direction (Y direction) and intersects the first direction ( A plurality of data lines (also referred to as cathode lines) DL arranged in parallel in the X direction) and a first direction (Y direction) extending in the second direction (X direction) and intersecting the second direction And a plurality of scanning lines SL arranged side by side. Electron emitting elements are formed at or near the intersection of the data lines DL and the scanning lines SL arranged in a matrix.

  One end of the scanning line SL is connected to the scanning driver SD. On the other hand, one end of the data line DL is connected to the data driver DD. The front substrate is disposed to face along the broken line portion in the drawing. The front substrate 2 and the rear substrate 1 are bonded along the outer periphery of the opposing region, and sealed by exhausting the internal gas. The above-described spacer is disposed on the scanning line SL.

  FIG. 7 is a plan view of an essential part seen from the inner surface side of the front substrate constituting the image display device according to the present invention. In FIG. 7, on the inner surface of the front substrate 2 made of a translucent glass material, a red phosphor layer PHR, a green phosphor layer PHG, and a blue phosphor along the length direction of the plurality of data lines DL shown in FIG. A phosphor screen PH having a layer PHB is formed, and a black matrix film BM that partitions the red phosphor layer PHR, the green phosphor layer PHG, and the blue phosphor layer PHB is formed on the phosphor screen PH.

  FIG. 8 is an enlarged cross-sectional view of the phosphor screen PH formed on the inner surface of the front substrate 2. In FIG. 8, each red phosphor layer PHR, green phosphor layer PHG, and blue phosphor layer PHB constituting the phosphor screen PH are formed so as to cover a part of the black matrix film BM. On the phosphor screen PH, a metal back film MT that efficiently reflects the light emitted from the red phosphor layer PHR, the green phosphor layer PHG, and the blue phosphor layer PHB is formed. An anode voltage is applied to the metal back film MT and functions as an anode electrode. The aforementioned spacer is disposed on the black matrix film BM.

  In the embodiment described above, a front substrate having a phosphor layer and a black matrix film on the inner surface and a metal back film (anode electrode) on the back surface of the phosphor layer and the black matrix film is used as the image display device. Although the case of applying to a display device has been described, the present invention is not limited to this.

  In the above-described embodiment, the case where the fixing members 11a and 11b for fixing the front substrate 1 and the back substrate 2 have different compositions on the front substrate 1 side and the back substrate 2 has been described. However, the same effect as described above can be obtained even when a fixing member having the same composition is used.

  In the above-described embodiments, the case where the image display device is applied to an FED using a front substrate having a phosphor and a black matrix on the inner surface and an anode on the back surface of the phosphor and the black matrix has been described. The present invention is not limited to this, and the same effects as described above can be obtained when applied to a plasma display (PDP), a panel display (MIM-FED) having a metal-insulator-metal electron emission source, or the like. Of course, is obtained.

  Furthermore, it is also possible to apply the hermetic sealing structure of the above-described embodiment to a sealing structure of a projector illumination lamp, a sealing structure of a heat insulating window glass, or a sealing structure of a vacuum device.

It is a schematic plan view which shows the structure by Example 1 of the image display apparatus by this invention. It is a principal part expanded sectional view of the AA 'line of FIG. It is an expanded sectional view which shows the structure of the side part of the support frame of FIG. It is a principal part expanded sectional view which shows the detail of the sealing structure of the support frame of FIG. It is a principal part expanded sectional view which shows the detail of the sealing structure of the support frame by Example 2 of the image display apparatus by this invention. It is a principal part top view which shows the structure of the back substrate of the image display apparatus by this invention. It is a principal part top view which shows the structure of the front substrate of the image display apparatus by this invention. It is a principal part expanded sectional view which shows the structure of the fluorescent screen formed in the front substrate of the image display apparatus by this invention. It is principal part sectional drawing which shows the basic structure of the conventional image display apparatus. It is a principal part expanded sectional view which shows the sealing structure of the support frame of the image display apparatus shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Front substrate, 2 ... Back substrate, 3 ... Support body, 4 ... Spacer (space | interval holding member), 5 ... Electron emission element, 51 ... Cathode wiring, 51a ... Cathode wiring lead-out line 52... Electron source 53... Control electrode 53 a Control electrode lead-out line 6 Image forming member 61 Phosphor film 62 Metal Back film 63 ... Black matrix film 10a ... Low melting point sealing member 10b ... Siloxane compound sealing member 11a ... Fixing member 11b ... Fixing member 12 ... Display region.

Claims (4)

A front substrate having an anode and a phosphor on the inner surface;
A back substrate having a plurality of electron sources on the inner surface and arranged to face the front substrate at a predetermined interval;
A frame-shaped support body that is inserted around a display area formed between the front substrate and the rear substrate, and that holds the predetermined interval;
A sealing member that hermetically seals the both end faces of the support and the front substrate and the rear substrate;
Have
An image display device for forming a vacuum container, wherein the end face of the support and the front substrate and the rear substrate are hermetically sealed with a sealing member interposed therebetween,
The image display device, wherein the sealing member is formed of a siloxane compound sealing member having at least a phenyl group on the vacuum side of the vacuum vessel.   The said siloxane compound sealing member which has a phenyl group consists of a silicone resin containing phenylheptamethylcyclotetrasiloxane and 2,6-cis-diphenylhexamethylcyclotetrasiloxane. Image display device.   The image display device according to claim 1, wherein the siloxane compound sealing member having a phenyl group is thermally cured at a temperature of 200 ° C. or more and 300 ° C. or less. The image display device according to claim 1, wherein the low melting point sealing member is made of low melting point frit glass that is thermally cured at a temperature of 300 ° C. or higher and 380 ° C. or lower.

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