JP2009129738A - Image display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To fix a spacer stably to an anode substrate and a cathode substrate in order to maintain a spacing between the anode substrate and the cathode substrate against the atmospheric pressure. <P>SOLUTION: The adhesion width of a crystalline frit glass 41 is larger than the adhesion width of an amorphous frit glass 42. In this case, the quantity of the frit glass 41 is larger than the quantity of the frit glass 42, and the contact angle of the frit glass 41 to the anode substrate 2 is smaller than the contact angle of the frit glass 42 to the cathode substrate 1. This structure is owing to the fact that when the anode substrate 2 is adhered by the frit glass 41, the frit glass 42 is also baked in a state of being coated on a spacer. Thereby, the spacer 4 can be installed stably and it is prevented that solvent from the frit glass remains in an FED. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a flat display device in which the inside is evacuated, the electron emission sources are arranged in a matrix on the rear substrate, and the phosphors corresponding to the front substrate are arranged. A spacer is stably placed inside the display device. Related to the technology to be installed.

  A field emission display (FED) is a display device in which an inside sandwiched between two glass substrates is evacuated, electron emission sources are arranged in a matrix on one substrate, and phosphors are arranged on a counter substrate. The FED forms an image when electrons from an electron emission source strike a phosphor and emits light. In the future, brightness, contrast, moving image characteristics, etc. can provide excellent performance similar to a cathode ray tube. It is expected as a TV display.

  However, in the FED, it is necessary to accelerate electrons to make the phosphor shine by applying a high voltage of about 10 KV to the anode. Since a high voltage of about 10 KV is applied between the anode substrate on which the phosphor screen is formed and the cathode substrate on which the electron source is formed, a considerably high electric field is formed inside the display device. Accordingly, sparks are likely to occur between the anode substrate and the cathode substrate.

  A spacer for withstanding atmospheric pressure is installed between the anode substrate and the cathode substrate. If this spacer is an insulator, electrons are charged on the surface, which affects the trajectory of the electron beam from the electron source. Further, when the spacer is charged, sparks are likely to occur between the anode substrate and the cathode substrate. In order to prevent this, a technique is known in which the spacer itself has a certain degree of conductivity, or a conductive material is applied to the surface of the spacer.

  The spacer is fixed to the anode substrate or the cathode substrate with frit glass or the like. “Patent Document 1” is given as a description of this fixing method. In addition, as a method for establishing conduction between the conductive spacer and the conductive film formed on the substrate, a frit mixed with a conductive filler is used, and a conductive substance is applied to an insulator such as glass particles as the conductive filler. A technique for coating is described in “Patent Document 2”. “Patent Document 3” describes a technique in which frit glass having hysteresis characteristics is used as a fixing material so that the stability of fixing of the spacer is not impaired by the thermal history after fixing the spacer with frit glass. ing.

JP 2002-124186 A JP-A-8-241049 JP 2005-5120 A

  The spacer must be electrically connected to the metal back on the anode substrate side and the scanning line on the cathode substrate side. In this case, conventionally, on the anode substrate side, a technique is known in which a spacer is fixed to the metal back using conductive frit glass and is electrically connected to the metal back. On the other hand, it is necessary to establish electrical continuity with the scanning line on the cathode substrate side. However, as described in “Patent Document 3,” when a conductive frit glass is used, the softening point of the frit on the anode side and the cathode side frit glass are used. Problems may occur due to frit sticking conditions.

  That is, when the spacer is fixed with a frit, it is necessary to perform baking at a high temperature of about 400 ° C. When the spacer is baked and fixed on the anode substrate side and then the spacer is baked and fixed on the cathode substrate side, when the cathode frit glass is baked, the frit glass on the anode side softens and the spacer is not fixed. The problem of becoming stable arises. In order to counter this problem, “Patent Document 1” describes the use of frit glass having hysteresis. However, this technique has a problem of mass productivity because it uses both ordinary frit glass and frit glass having hysteresis.

  On the other hand, when baking the frit glass on the cathode side of the spacer, gas is generated from the frit glass to contaminate the electron source, resulting in a problem that the electron emission efficiency is lowered.

  In order to avoid such a problem, there is a technique in which the spacer is adhered only to the anode substrate side by the frit glass, and the frit glass is not used on the cathode substrate side. In place of not using frit glass on the cathode substrate side, there is a technique in which a metal such as Mo is attached to the end face of the spacer on the cathode substrate side by sputtering to establish conduction with the scanning line formed on the cathode substrate side.

  That is, after the spacer is fixed by frit glass on the anode substrate side, the entire FED is sealed only by pressing the spacer from above on the scanning line of the cathode substrate. After sealing the FED, the inside of the FED is evacuated to a vacuum. Then, the anode substrate and the cathode substrate are pressed by the atmospheric pressure. As a result, since the spacer is pressed by the anode substrate and the cathode substrate, the spacer and the scanning line can be electrically connected even if the cathode substrate is not fixed with a conductive adhesive or the like.

  However, for this purpose, the cathode side end face of the spacer needs to be metallized with Mo or the like. Melalization is performed by sputtering, but this sputtering step is a work time and causes a cost increase. In this method, although the spacer can be electrically connected, the spacer is not fixed on the cathode substrate side, so the reliability of fixing the spacer is inferior to the case where the spacer is fixed with frit glass or the like. .

  The present invention has been made to solve the above-described conventional problems. The conductive frit glass is also used on the cathode side of the spacer, and the characteristics of the frit glass and the method for baking the frit glass applied to the spacer are provided. Thus, the spacer is stably placed between the anode substrate and the cathode substrate. In the present invention, the cathode side end face of the spacer need not be metallized. The specific configuration is as follows.

  A cathode substrate in which an electron source is formed in a matrix and an anode terminal to which an anode voltage is applied are opposed to the cathode substrate, and a phosphor is formed at a location corresponding to the electron source to form an effective screen. A conductive spacer is provided between the cathode substrate and the anode substrate to define a distance between the cathode substrate and the anode substrate, and a peripheral portion of the cathode substrate and the anode substrate is disposed between the cathode substrate and the anode substrate. Is a display device in which a sealing portion is formed and the inside is maintained in a vacuum, wherein the spacer is fixed to one substrate by a first frit glass, and the spacer is attached to another substrate by a second frit glass. The first frit glass is a crystalline frit glass, and the second frit glass is an amorphous frit glass. Serial bonding width between the first frit glass and said one of the substrates, a display device, wherein the second frit glass and greater than the adhesive width of the other substrate scan lines.

  (2) The display device according to (1), wherein an amount of the first frit glass is larger than an amount of the second frit glass.

  (3) The contact angle between the first frit glass and the one substrate is an acute angle, and the contact angle between the second frit glass and the other substrate is an obtuse angle (1) The display device described in 1.

(4) the first frit glass and the second frit glass is _V 2 _{O 5} 40 wt% or _more, the display device according to P 2 _{O 5} to (1), characterized in that it comprises 20 wt% or more .

  (5) The display device according to (1), wherein the volume resistivity of the second frit glass is smaller than the volume resistivity of the first frit glass.

  (6) The display device according to (1), wherein the volume resistivity of the first frit glass and the volume resistivity of the second frit glass are smaller than the volume low efficiency of the spacer.

(7) The first frit glass and the second frit glass contain V ₂ O _{5 in an amount} of 40% by weight or more and P ₂ O _{5 in an amount} of 20% by weight or more, and in the second frit glass of V ₂ O ₅ (1) The display device according to (1), wherein a component ratio is larger than a component ratio of V ₂ O ₅ in the first frit glass.

  (8) The baking temperature at which the spacer is fixed to the one substrate side by the first frit glass is higher than the temperature at which the spacer is fixed to the other substrate side by the second frit glass. The display device according to (1).

  (9) A cathode substrate in which an electron source is formed in a matrix, an anode terminal to which the anode voltage is applied, facing the cathode substrate, and a phosphor is formed at a location corresponding to the electron source and effective. An anode substrate having a screen formed thereon, and a conductive spacer defining a distance between the cathode substrate and the anode substrate is disposed between the cathode substrate and the anode substrate; In the display device, a sealing portion is formed in a peripheral portion and the inside is maintained in a vacuum. The spacer is fixed to a metal back formed on the anode substrate by a first frit glass, and the spacer is The first frit glass is a crystalline frit glass fixed to a scanning line formed on the cathode substrate by a frit glass of 2. The second frit glass is an amorphous frit glass, the contact angle of the first frit glass with the metal back is an acute angle, and the second frit glass is in contact with the scanning line. A display device characterized in that the angle is an obtuse angle.

  (10) The baking temperature at which the spacer is fixed to the anode substrate side by the first frit glass is higher than the temperature at which the spacer is fixed to the cathode substrate side by the second frit glass. The display device according to (9).

  (11) A cathode substrate in which an electron source is formed in a matrix, an anode terminal to which an anode voltage is applied, facing the cathode substrate, and a phosphor is formed at a location corresponding to the electron source is effective. An anode substrate having a screen formed thereon, and a conductive spacer defining a distance between the cathode substrate and the anode substrate is disposed between the cathode substrate and the anode substrate; A display device in which a sealing portion is formed in a peripheral portion and the inside is maintained in a vacuum, wherein the sealing portion seals a sealing frame, the sealing frame, and the anode substrate. The frit glass is constituted by a second frit glass that seals the sealing frame and the cathode substrate, and the first frit glass is a crystalline frit glass, The frit glass of 2 is an amorphous frit glass, and the adhesion width of the first frit glass to the anode substrate is larger than the adhesion width of the second frit glass to the cathode substrate. Display device.

  (12) The contact angle between the first frit glass and the anode substrate is an acute angle, and the contact angle between the second frit glass and the cathode substrate is an obtuse angle. Display device.

  According to the present invention, the spacer is stabilized by giving a special relationship to the shape and characteristics of the frit glass for fixing the spacer to the anode substrate side and the shape and characteristics of the frit glass for fixing the spacer to the cathode substrate side. Can be installed.

  Also, by applying the frit glass on the cathode substrate side of the spacer before baking the frit glass on the anode substrate side of the spacer, the gas released from the cathode substrate side is released into the atmosphere without remaining in the FED. I can do it. Therefore, it is possible to prevent the electron source from being contaminated by the gas released from the frit glass.

  Furthermore, in the present invention, it is not necessary to metallize the end surface of the spacer on the cathode substrate side, so that the metallization process can be omitted and the manufacturing cost is reduced. The application of the conductive frit glass on the cathode side of the spacer of the present invention is simpler than metallization, and the manufacturing cost can be reduced compared to metallization.

  The best mode of the present invention will be described below in detail with reference to the drawings of the embodiments.

  FIG. 1 is a plan view showing a first embodiment of the present invention. In FIG. 1, an anode substrate 2 is installed on a cathode substrate 1 via a sealing portion 3. On the cathode substrate 1, scanning lines extend in the horizontal direction, and data signals extend in the vertical direction. A signal is supplied to the scanning line and the data signal line from the outside via the terminal 5. An electron emission source is disposed near the intersection of the scanning line and the signal line. Therefore, a large number of electron emission sources are arranged in a matrix. Various electron emission sources such as the so-called MIM system, SED system, Spindt system, and carbon nanotube have been developed, and any electron emission source can be applied to the present invention.

  The inside of the sealing part 3 surrounding the cathode substrate 1 and the anode substrate 2 and the periphery is kept in a vacuum. Therefore, the anode substrate 2 and the cathode substrate 1 are bent by the atmospheric pressure, and the interval between the cathode substrate 1 and the anode substrate 2 cannot be secured. Alternatively, the cathode substrate 1 or the anode substrate 2 is destroyed. In order to avoid this, a spacer 4 is provided between the cathode substrate 1 and the anode substrate 2. The spacer 4 is made of ceramic or glass and is generally installed on the scanning line so as not to hinder image formation.

  The spacer 4 is installed on the scanning line of this effective screen area. On the anode substrate 2, red, green, and blue phosphors 21 that emit light by an electron beam projection are formed corresponding to the electron emission sources. A black matrix (BM22) is formed around the phosphor 21 to improve image contrast. A metal back 23 made of Al is formed so as to cover the black matrix. A high voltage is applied to the metal back 23, and the electron beam emitted from the cathode is accelerated and projected onto the phosphor 21.

  In order to generate light from the phosphor 21 by the electron beam, the electron beam must have a certain amount of energy, and therefore, a high voltage of 8 KV to 10 KV is applied to the metal back 23 of the anode substrate 2. In this embodiment, a high voltage introduction terminal 60 for supplying a high voltage from the outside is provided on the cathode substrate 1 side, and a high voltage is supplied to the anode substrate 2 through a contact spring. Since the inside of the display device must be kept in vacuum, an exhaust hole 81 and an exhaust pipe 8 are provided on the back side of the display device in FIG.

  FIG. 2 is a side view of FIG. 1 viewed from the D direction. In FIG. 2, the cathode substrate 1 and the anode substrate 2 face each other with a predetermined distance through the sealing portion 3. The cathode substrate 1 is formed larger as the terminals 5 and the like are installed. Under the cathode substrate 1, an exhaust substrate 6 for attaching the exhaust pipe 8 and a high voltage introduction terminal is attached. The exhaust substrate 6 is attached to the cathode substrate 1 through an exhaust substrate sealing portion. In FIG. 2, an exhaust pipe 8 for evacuating the inside of the display device is drawn on the exhaust substrate 6 in a state where the chip is turned off.

3 is a cross-sectional view taken along the line AA in FIG. In FIG. 3, the data signal line 12 extends in a direction perpendicular to the paper surface. In this embodiment, an electron emission source 14 is formed on the data signal line 12. The scanning line 11 is formed in a direction perpendicular to the data signal line 12 through the insulating film 13. In FIG. 3, the scanning line 11 extends outside the sealing portion 3. A spacer 4 for maintaining the distance between the cathode substrate 1 and the anode substrate 2 is provided on the scanning line 11. The spacer 4 is fixed to the metal back 23 by a frit glass 41 on the anode substrate 2 side and on the scanning line by a frit glass 42 on the cathode substrate 1 side. The spacer 4 is provided with a conductivity of about 10 ⁷ to 10 ¹¹ Ω · cm, preferably about 10 ⁸ to 10 ⁹ Ω · cm. The spacer 4 has a scanning line on the cathode substrate 1 side and a metal back 23 on the anode substrate 2 side. The spacer 4 is prevented from being charged by passing a slight current between them.

  In order to keep the inside of the display device in a vacuum, the anode substrate 2 and the sealing frame 31 are sealed by the sealing material 32, and the cathode substrate 1 and the sealing frame 31 are sealed by the sealing material 33. In this embodiment, the sealing material 32 and the sealing material 33 use different types of frit glass having different bonding temperatures.

  On the anode substrate 2 side, phosphors 21 such as red, green, and blue are arranged at locations corresponding to the electron emission sources 14, and the phosphors 21 emit light by being projected onto the electron beam, and an image is displayed. It is formed. The space between the phosphors 21 is filled with BM 22 and contributes to the improvement of the contrast of the image. For example, the BM 22 has a two-layer structure of chromium and chromium oxide. A metal back 23 made of Al is formed so as to cover the phosphor 21 and the BM 22. A high voltage of about 8 KV to 10 KV is applied to the metal back 23 to accelerate the electron beam. The accelerated electron beam penetrates the metal back 23 and strikes the phosphor 21 to cause the phosphor 21 to emit light.

  In FIG. 3, after the anode substrate 2 and the cathode substrate 1 are sealed through the sealing frame 31 and the frit glass, the inside of the FED is evacuated to a vacuum through the exhaust pipe. The thickness of the cathode substrate 1 and the thickness of the anode substrate 2 are about 3 mm. The distance between the cathode substrate 1 and the anode substrate 2 is about 2.8 mm. In order to apply a high voltage of 8 KV to 10 KV at this narrow interval, a high electric field is formed inside the display device, and there is a danger of sparking. In order to prevent sparks, the spacer 4 and the frit glass to which the spacer 4 is fixed are provided with electrical conductivity to prevent the spacer 4 from being charged.

  FIG. 4 is a schematic view showing a CC cross section of FIG. In FIG. 4, data signal lines 12 extend in the horizontal direction on the cathode substrate 1. The scanning line 11 extends in the normal direction of the paper surface at right angles to the data signal line 12. An electron source 14 is disposed on the data signal line 12 between the scanning lines. The electron source 14 includes a data signal line 12 serving as a lower electrode and an upper electrode that is electrically connected to the scanning line 11 via a tunnel insulating film. In this embodiment, an MIM electron source is used as the electron source 14, but the present invention is not limited to the MIM electron source but can be applied to other electron sources.

  A phosphor 21 is formed on the anode substrate 2 and the space between the phosphor and the phosphor is covered with a BM 22. A metal back 23 is formed by sputtering Al over the phosphor 21 and the BM 22. An anode voltage that is a high voltage of about 8 KV to 10 KV is applied to the metal back 23. The electron beam emitted from the electron source 14 is accelerated by the anode voltage. The electron beam emitted from the electron source 14 penetrates the metal back 23 and strikes the phosphor 21 to cause the phosphor 21 to shine, thereby forming a color image. The electron beam spreads when emitted from the electron source 14, but is designed to be slightly larger than each phosphor on the phosphor screen.

  In order to maintain the distance between the anode substrate 2 and the cathode substrate 1, the spacer 4 is installed as described with reference to FIG. The spacer 4 is disposed between the scanning line 11 on the cathode substrate 1 and the metal back 23 on the anode substrate 2. At this position, the spacer 4 does not interfere with image formation.

  5 is a cross-sectional view taken along the line BB of FIG. In FIG. 5, a through hole 10 is formed in the cathode substrate 1, and the display device is exhausted or a high voltage is supplied through the through hole 10. An exhaust substrate 6 is installed through the exhaust substrate sealing portion 7 so as to cover the through hole 10 of the cathode substrate 1, and the inside of the display device is kept in vacuum. The exhaust substrate sealing portion 7 has the same basic configuration as the cathode substrate 1 and the anode substrate 2 sealing portion 3. That is, the exhaust substrate frame 71 is sealed with the frit glass 32, and the exhaust substrate frame 71 is sealed with the cathode substrate 1 with the frit glass 33. In this embodiment, the frit glass 32 has a higher bonding temperature than the frit glass 33. In this embodiment, the frame 31 for sealing the anode substrate 2 and the cathode substrate 1 and the frame for sealing the cathode substrate 1 and the exhaust substrate 6 have the same thickness, but the thickness of the frame is as required. Can be set freely.

The high voltage introduction terminal 60 penetrates the exhaust board 6 while maintaining airtightness with the outside. The high voltage introduction terminal 60 is sealed with the exhaust substrate 6 by the frit glass 32.
An Fe—Ni alloy is used for the high voltage introduction terminal 60, but the ratio of Fe and Ni is determined in consideration of the thermal expansion of the exhaust substrate 6. In this example, Ni is 48%. An exhaust hole 81 is formed in the exhaust substrate 6, and an exhaust pipe 8 is sealed in the exhaust hole 81 via a frit glass 32. The inside of the display device is evacuated through the exhaust pipe 8, and then the exhaust pipe 8 is chipped off and the inside of the display device is kept in vacuum. FIG. 5 shows a state where the exhaust pipe 8 is chipped off.

  The frit glass 32 has a higher bonding temperature than the frit glass 33, and accordingly, the reliability of sealing the exhaust pipe and the high voltage introduction terminal is increased. In other words, since the exhaust pipe and the high voltage introduction terminal are sealed regardless of the baking of the cathode terminal on which the electron source is formed, the reliability of the sealing is increased by using frit glass having a high bonding temperature. ing.

  An anode terminal 24 for contacting the contact spring 50 is formed on the anode substrate 2. Since a relatively large current flows through the anode terminal 24, reliability is important. In this embodiment, the structure near the anode terminal 24 is as follows. A BM 22 of chromium and chromium oxide is formed on the anode substrate 2, and a metal back 23 made of Al is formed so as to cover the BM 22. This is the same configuration as the effective screen of the screen. In this embodiment, a conductive film as the anode terminal 24 is formed on the metal back 23 with a thickness of about 10 μm.

  In this embodiment, the anode terminal 24 is formed by applying a silver paste by printing and then baking it. There is no need to provide a special process for firing the anode terminal 24. For example, the anode terminal 24 may be performed simultaneously with the firing process when the spacer 4 is fixed.

  The silver paste is obtained by dispersing silver particles having a diameter of 1 μm to several μm in an organic solvent having a high viscosity. After firing, the silver particles are connected to each other to have conductivity. In some cases, the conductive film should have some resistance. In such a case, the resistance can be adjusted by further mixing a paste for frit glass with a normal silver paste. Note that the material of the conductive film is not limited to silver paste, and Ni paste in which Ni particles are dispersed, Al paste in which Al particles are dispersed, and the like can also be used. A graphite film bonded with a binder can also be used. The graphite in this case is preferably graphite. The resistance of the graphite film can be adjusted, for example, by mixing bengara (iron oxide) with graphite.

  FIG. 6 is a schematic cross-sectional view of an FED showing the state of fixing of the spacer 4 by frit glass in the present invention. In FIG. 6, the spacer 4 is fixed on the anode substrate 2 side via the metal back 23 and the frit glass 41, and is fixed on the cathode substrate 1 side via the scanning line and the frit glass 42. In FIG. 6, data signal lines, electron sources, and the like formed on the cathode substrate 1 are omitted to simplify the drawing.

In FIG. 6, crystallized frit glass is used for the frit glass 41 on the anode side. As the frit glass 42 on the cathode side, amorphous frit glass is used. All the frit glasses are conductive and have a volume resistivity of 10 ² to 10 ⁹ Ωcm. The volume resistivity of the frit glass is smaller than the volume resistivity of the spacer 4. Further, as will be described later, the volume resistivity of the frit glass 42 on the cathode side is smaller than the volume resistivity of the frit glass 42 on the anode side.

In the case of the conductive frit glass of vanadium type (hereinafter referred to as V type), the conductive frit glass contains V ₂ O ₅ in a weight ratio of 40% or more and P ₂ O ₅ in a weight ratio of 20% or more. On the other hand, the conductive frit glass can also be composed of Pb-based or Bi-based frit glass. In this case, it contains metal particles such as Ag or Au.

  In FIG. 6, the frit glass 41 used on the anode side is crystallized by baking, and after crystallized, it has a property that it is difficult to soften by reheating. Since the anode substrate 2 is subjected to a thermal history such as baking for bonding the cathode substrate 1 after bonding to the spacer 4, crystallized glass is advantageous in this respect. When amorphous frit glass is used on the anode side, it is preferable to use frit glass whose softening temperature is higher than the baking temperature of the cathode substrate 1.

  In FIG. 6, when the frit glass 41 is bonded to the spacer 4 and the metal back 23 formed on the anode substrate 2, the frit glass 41 melts and gets wet with the metal back 23. That is, the contact angle with the metal back 23 is an acute angle. The baking temperature is as follows. Further, the amount of the frit glass 41 is larger than the amount of the frit glass 42 on the cathode substrate 1 side. By doing so, the adhesive strength between the spacer 4 and the anode substrate 2 is increased.

  On the other hand, amorphous frit glass is used as the frit glass 42 for bonding the spacer 4 and the cathode substrate 1. Amorphous frit glass has the property of being softened by being exposed to a high temperature again after being bonded once. The fritted glass 42 has an obtuse angle with the scanning line by a process described later.

FIG. 7 shows an application method for applying frit glass to the spacer 4. A frit glass 41 for bonding to the anode substrate 2 is placed on the coating table 110. When the end face of the spacer 4 is brought into contact with the frit glass 41 placed on the application table 110, the frit glass 41 is applied. The frit glass 41 is, for example, a conductive frit glass in which ZnO is mixed with a V-based frit glass. V-type frit glass is composed of V ₂ O ₅ as a conductive component and P ₂ O ₅ as a glass component, and BaO is added thereto. The components of the frit glass 41 are 40% by weight or more of V ₂ O _{5 and} 20% by weight or more of P ₂ O ₅ . ZnO added to the frit glass 41 reacts with P ₂ O ₅ which is a glass component to form Zn ₃ (PO ₄ ) ₂ and crystallize.

After the frit glass 41 is applied to the spacer 4 that adheres to the anode side, the spacer 4 is reversed, and the other end surface that comes into contact with the cathode side is brought into contact with the frit glass 42 placed on the application table 110, so Is applied to the spacer 4. Similarly to the anode-side frit glass, a V-type frit glass in which V ₂ O ₅ is a conductive component and P ₂ O ₅ is a glass component and BaO is added to the cathode-side frit glass is used. The components of the frit glass 42 are V ₂ O ₅ of 40% by weight or more and P ₂ O ₅ of 20% by weight or more. However, ZnO for crystallization is not added to the frit glass 42. This is because the frit glass 42 is used as an amorphous material.

The cathode-side frit glass 42 uses V-based conductive frit glass, but the content of V ₂ O ₅ is larger than that of the anode-side frit glass 41, and the volume resistivity is accordingly reduced. . On the cathode side, if the resistance of the spacer 4 is large, the electron beam is deflected by the potential difference at this portion. In order to prevent this, the resistance of the frit glass 42 on the cathode side is made smaller than the resistance of the frit glass 41 on the anode side. As described above, the application of the frit glass to the spacer 4 is simpler than the process of sputtering a metal on the end face of the spacer 4, and the manufacturing cost can be reduced accordingly.

  After the frit glass is applied to both surfaces of the spacer 4 in this way, the spacer 4 is first bonded to the anode substrate 2 side by the frit glass 41 as shown in FIG. The spacer 4 coated with the frit glass 41 is placed on the metal back 23 of the anode substrate 2 and baked. The baking temperature at this time is 400 ° C. to 440 ° C. FIG. 8 shows a state in which the spacer 4 is bonded to the anode substrate 2. The contact angle between the frit glass 41 and the metal back 23 is an acute angle. That is, the frit glass 41 has a property of sufficiently fluidizing at a baking temperature of 400 ° C. to 440 ° C.

  FIG. 11 is a graph showing the differential thermal reaction of the crystallized frit glass 41. In FIG. 11, the horizontal axis represents temperature, and the vertical axis represents heat generation or endotherm. That is, on the vertical axis, the case where the projection is above the baseline is an exothermic reaction, and the case where the projection is below the baseline is an endothermic reaction. An exothermic reaction occurs at the ts point, which is the strain point, a peak of exotherm occurs at the transition point tg, and an endothermic reaction occurs when the temperature is further raised.

  The Mg point in FIG. 11 corresponds to the yield point in the case of measuring the thermal expansion coefficient, and the endotherm is maximized. When the temperature is further raised, an exothermic reaction occurs again, and reaches the softening point tsoft through a peak of the exothermic reaction. After the softening point, crystallization occurs and an exothermic reaction occurs. In practice, crystallization proceeds as soon as the softening point is reached. B shown in FIG. 11 is a crystallization peak. When the crystallization is completed, an irreversible phenomenon occurs, and the crystallized frit glass does not soften even when heated to the softening temperature again. This is a characteristic of crystallized frit glass.

  When adhering the spacer 4 to the anode substrate 2, a frit glass 42 for adhering to the cathode side is also applied to the other end face of the spacer 4 and baked at the same time. The frit glass 42 is an amorphous frit glass. Since the frit glass 42 is baked before being bonded to the cathode substrate 1, it has a round shape as shown in FIG. When applied, the frit glass contains various organic solvents. When the organic solvent remains in the FED, it adversely affects the electron emission characteristics of the electron source. In the present invention, since both the frit glass 41 and the frit glass 42 are baked before sealing the cathode substrate 1, the solvent contained in the frit glass has an advantage that it hardly remains in the FED.

  FIG. 9 is a view in which the cathode substrate 1 is bonded to the sealing frame 31 or the spacer 4 after the spacer 4 is attached to the anode substrate 2. The baking temperature for bonding the cathode substrate 1 and the spacer 4 is 370 ° C. to 430 ° C. The frit glass 42 is an amorphous frit glass, and the deformation temperature of the frit glass is 370 ° C. to 430 ° C.

  FIG. 12 is a diagram showing the temperature change of the thermal expansion coefficient of glass. In FIG. 12, the horizontal axis represents temperature, and the vertical axis represents thermal expansion. After the transition temperature Tg, the expansion of the glass rapidly increases, and the elongation becomes maximum at the deformation temperature At. The frit glass 42 on the cathode side adheres to the scanning line on the cathode substrate 1 side at the deformation temperature At.

  In the differential thermal reaction of the glass shown in FIG. 11, the crystallized frit glass behaves in the same manner as the amorphous frit glass up to region A in FIG. 11, that is, up to tsoft. However, since the amorphous frit glass 42 is not crystallized, it softens again when the temperature is raised. The amorphous frit glass 42 adheres at the deformation temperature, which corresponds to the peak between Mg and tsoft in FIG. As described above, this temperature is 370 ° C. to 430 ° C., which is slightly lower than the softening point 400 ° C. to 440 ° C. of the crystallized frit glass 41.

  The cathode-side frit glass 42 is baked and solidified when the anode substrate 2 and the spacer 4 are bonded, but is deformed by baking again at 370 ° C. to 430 ° C. to bond the spacer 4 and the cathode substrate 1 together. Will be able to. This is the reason why amorphous frit glass is used for the frit glass 42 on the cathode side. After sealing the cathode substrate 1, the inside of the FED is evacuated to a vacuum.

  FIG. 10 shows a state where the spacer 4 is installed between the anode substrate 2 and the cathode substrate 1 in this way. In FIG. 10, the width w1 of the frit glass 41 on the anode substrate 2 side is larger than the width w2 of the frit glass 42 on the cathode side. This is because, in addition to the amount of the frit glass 41 being larger than the amount of the frit glass 42, the frit glass 42 is softened once again and bonded to the cathode substrate 1. It is because it adheres without fluidizing.

  Further, the contact angle A1 of the frit glass 41 on the anode side in FIG. 10 is an acute angle, whereas the contact angle A2 on the cathode side is an obtuse angle for the same reason. That is, when the anode side is bonded, the frit glass 41 flows sufficiently, whereas when the cathode side is bonded, the frit glass 42 is already solidified and bonded without flowing sufficiently. . However, the seal hardening can be sufficiently increased.

  In the first embodiment, the present invention is applied to the spacer 4. However, the present invention can be applied not only to the spacer 4 but also to the case where the sealing frame 31 is sealed to the anode substrate 2 or the cathode substrate 1. . This is because the frit glass is also used for sealing the sealing frame 31 to the anode substrate 2 or the cathode substrate 1.

  FIG. 13 is a cross-sectional view showing the second embodiment. FIG. 13 is the same as FIG. 6 in the first embodiment except for the sealing frame 31. In FIG. 13, the frit glass 32 that bonds the sealing frame 31 and the anode substrate 2 is a crystalline frit glass similar to the frit glass 41 that bonds the spacer 4 and the anode substrate 2. However, unlike the frit glass 42, the frit glass 32 does not have conductivity. As the frit glass 32, lead-based frit glass, bismuth-based frit glass, tin-based frit glass, insulating vanadium-based frit glass, or the like is used, but it is crystallized at the time of baking using an additive.

  The anode substrate 2 and the sealing frame 31 are bonded at the same time by a baking process for bonding the anode substrate 2 and the spacer 4. When the frit glass 32 is bonded to the anode substrate 2, the frit glass 32 is sufficiently fluidized and bonded, so that the wettability with the anode substrate 2 is good and the contact angle between the frit glass 32 and the anode substrate 2 is an acute angle. .

  When the sealing frame 31 and the anode substrate 2 are bonded by baking, a frit glass 33 for bonding the sealing frame 31 and the cathode substrate 1 is applied to the sealing frame 31. Therefore, the frit glass 33 applied to the opposite side of the sealing frame 31 at the time of baking for bonding the sealing frame 31 to the anode substrate 2 is also solidified. At this time, the organic solvent or the like contained in the frit glass 33 evaporates. Therefore, the electron source is not contaminated by the evaporated material from the frit glass 33.

  Since the frit glass 33 is made of amorphous frit glass, it can be softened by baking when the cathode substrate 1 is bonded to the sealing frame 31, and the sealing frame 31 and the cathode substrate 1 can be bonded. Like the frit glass 32, the frit glass 33 may be a lead-based frit glass, a bismuth-based frit glass, a tin-based frit glass, a vanadium-based frit glass, or the like, but ZnO is not added. This is because the frit glass 33 is used in an amorphous state.

  When the sealing frame 31 and the cathode substrate 1 are bonded, the frit glass 33 is already solidified, so that when the cathode substrate 1 and the sealing frame 31 are bonded, they are not sufficiently fluidized. Therefore, the contact angle between the frit glass 33 and the cathode substrate 1 is an obtuse angle. However, the sealing effect does not change. The width w3 of the frit glass 32 that bonds the sealing frame 31 and the anode substrate 2 is larger than the width w4 of the frit glass 33 that bonds the sealing frame 31 and the cathode substrate 1. This is because the amount of the frit glass 32 is larger than the amount of the frit glass 33 and the contact angle of the frit glass 32 is smaller than that of the frit glass 33.

As described above, according to the present invention, the spacer 4 can be stably fixed to the anode substrate 2 and the cathode substrate 1. In addition, the organic solvent from the frit glass applied to the spacer 4 can be scattered and removed outside before sealing inside the FED, thereby preventing contamination of the electron source or deterioration of the vacuum degree. I can do it.
In addition, appropriate conductivity can be provided between the cathode substrate 1 and the anode substrate 2, deflection of the electron beam due to charging of the spacer 4 can be prevented, and spark can be prevented. Further, by using the present invention for the sealing frame 31 that seals the anode substrate 2 and the cathode substrate 1, highly reliable sealing can be performed.

It is a top view of FED of this invention. It is a side view of FIG. It is AA sectional drawing of FIG. It is CC sectional drawing of FIG. It is BB sectional drawing of FIG. 1 is a schematic cross-sectional view of Example 1. FIG. This is a frit glass coating process. It is sectional drawing which shows adhesion | attachment of an anode substrate and a spacer. It is sectional drawing which shows adhesion | attachment of a cathode substrate and a spacer. It is an enlarged view which shows the adhesion state of frit glass. It is a figure which shows the differential thermal reaction of crystalline frit glass. It is a figure which shows the thermal expansion coefficient of glass. 3 is a schematic cross-sectional view of Example 2. FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Cathode substrate, 2 ... Anode substrate, 3 ... Sealing part, 4 ... Spacer, 5 ... Terminal, 6 ... Exhaust substrate, 8 ... Exhaust pipe, 10. .. Through hole, 11... Scanning line, 12... Data signal line, 13 .. insulating film, 14... Electron source, 21. -Metal back, 23 ... anode terminal, 31 ... sealing frame, 32, 33, 41, 42 ... frit glass, 50 ... contact spring, 110 ... coating table.

Claims (12)

A cathode substrate in which an electron source is formed in a matrix and an anode terminal to which an anode voltage is applied are opposed to the cathode substrate, and a phosphor is formed at a location corresponding to the electron source to form an effective screen. A conductive spacer is provided between the cathode substrate and the anode substrate to define a distance between the cathode substrate and the anode substrate, and a peripheral portion of the cathode substrate and the anode substrate is disposed between the cathode substrate and the anode substrate. Is a display device in which a sealing part is formed and the inside is kept in vacuum,
The spacer is fixed to one substrate by a first frit glass, the spacer is fixed to another substrate by a second frit glass,
The first frit glass is a crystalline frit glass, the second frit glass is an amorphous frit glass, and the bonding width between the first frit glass and the one substrate is the first frit glass. 2. A display device characterized in that it is larger than the bonding width between the second frit glass and the other substrate scanning line.   The display device according to claim 1, wherein an amount of the first frit glass is larger than an amount of the second frit glass.   The contact angle between the first frit glass and the one substrate is an acute angle, and the contact angle between the second frit glass and the other substrate is an obtuse angle. Display device. Wherein the first frit glass second frit glass is V ₂ O ₅ 40 wt% or more, the display device according to claim 1, characterized in that it comprises a P ₂ O ₅ 20 wt% or more.   2. The display device according to claim 1, wherein a volume resistivity of the second frit glass is smaller than a volume resistivity of the first frit glass.   2. The display device according to claim 1, wherein the volume resistivity of the first frit glass and the volume resistivity of the second frit glass are smaller than the volume low efficiency of the spacer. Wherein the first frit glass second frit glass is _V 2 _{O 5} to 40% by weight or _more, includes a P 2 _{O 5} 20 wt% or _more, the component ratio in the second frit glass of V 2 _{O 5} is The display device according to claim 1, wherein the display device is larger than a component ratio of V ₂ O ₅ in the first frit glass.   The baking temperature at which the spacer is fixed to the one substrate side by the first frit glass is higher than the temperature at which the spacer is fixed to the other substrate side by the second frit glass. Item 4. The display device according to Item 1. A cathode substrate in which an electron source is formed in a matrix and an anode terminal to which an anode voltage is applied are opposed to the cathode substrate, and a phosphor is formed at a location corresponding to the electron source to form an effective screen. A conductive spacer is provided between the cathode substrate and the anode substrate to define a distance between the cathode substrate and the anode substrate, and a peripheral portion of the cathode substrate and the anode substrate is disposed between the cathode substrate and the anode substrate. Is a display device in which a sealing part is formed and the inside is kept in vacuum,
The spacer is fixed to a metal back formed on the anode substrate by a first frit glass, and the spacer is fixed to a scanning line formed on the cathode substrate by a second frit glass.
The first frit glass is a crystalline frit glass, the second frit glass is an amorphous frit glass, and the contact angle of the first frit glass with the metal back is an acute angle, A display device, wherein a contact angle of the second frit glass with the scanning line is an obtuse angle.   The baking temperature at which the spacer is fixed to the anode substrate side by the first frit glass is higher than the temperature at which the spacer is fixed to the cathode substrate side by the second frit glass. The display device described in 1. A cathode substrate in which an electron source is formed in a matrix and an anode terminal to which an anode voltage is applied are opposed to the cathode substrate, and a phosphor is formed at a location corresponding to the electron source to form an effective screen. A conductive spacer is provided between the cathode substrate and the anode substrate to define a distance between the cathode substrate and the anode substrate, and a peripheral portion of the cathode substrate and the anode substrate is disposed between the cathode substrate and the anode substrate. Is a display device in which a sealing part is formed and the inside is kept in vacuum,
The sealing portion includes a sealing frame, a first frit glass that seals the sealing frame and the anode substrate, and a second frit glass that seals the sealing frame and the cathode substrate. Configured,
The first frit glass is a crystalline frit glass, the second frit glass is an amorphous frit glass, and an adhesion width of the first frit glass with the anode substrate is the second frit glass. A display device, wherein the width of adhesion of the frit glass to the cathode substrate is larger.   The display device according to claim 11, wherein a contact angle of the first frit glass with the anode substrate is an acute angle, and a contact angle of the second frit glass with the cathode substrate is an obtuse angle. .

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