JP2007227230A - Spacer plantation structure and display device having the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To surely electrically connect a spacer to a back substrate and a front substrate. <P>SOLUTION: A back panel PNL1 is stuck to a front panel PNL2, and an internal space where both the panels face to each other therein is sealed in a pressure-reduced or vacuum state. The back substrate SUB1 constituting the back panel PNL1 is provided with multiple electron sources ELS arranged in a matrix-like form; and the front substrate SUB2 constituting the front panel PNL2 is provided with a phosphor layer PH, and a positive electrode AD for forming an acceleration voltage for forming an electric field for hitting electrons e<SP>-</SP>emitted from the electron sources ELS against the phosphor layer PH. In this spacer plantation structure, spacers SPCs each composed of core glass CRG and coat glass SRG of a high-resistance layer covering a surface of the core glass CRG are directly jointed and planted to/on the back panel PNL1 and the front panel PNL2 by using adhesive layers FGS. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a spacer planting structure that holds a gap between insulating substrates constituting a decompression space at a predetermined value, and a display device including the spacer planting structure.

  As a display device using a display panel obtained by bonding two flat insulating substrates (back substrate and front substrate), so-called flat display device (flat display: FPD), for example, thin film electrons arranged in a matrix A display device having a source attracts attention, and as one of them, an electron emission type display device using a small and accumulating cold cathode is known.

FIG. 6 is a schematic cross-sectional view illustrating the basic configuration of an electron emission display device using a metal film-insulating film-metal film type electron source as an electron source. This display device is provided on the main surface of a first substrate (insulating substrate, hereinafter also simply referred to as a back substrate) SUB1, and extends in the first direction and is arranged in parallel in a second direction intersecting the first direction. A plurality of scanning lines GL, a plurality of signal lines CL provided below the scanning lines GL, extending in the second direction and arranged in parallel in the first direction, and in the vicinity of the intersection of the scanning lines GL and the signal lines CL A back panel PNL1 having an electron source provided in
A second substrate (transparent insulating substrate, also simply referred to as a front substrate hereinafter) SUB2, a phosphor layer PH provided on the main surface of the front substrate SUB2 and paired with each of the electron sources ELS, and an anode AD A front panel PNL2 having
A sealing frame that forms a decompression container together with both panels by inserting the main surfaces, that is, the inner surfaces of the rear panel PNL1 and the front panel PNL2 facing each other, where the inner surfaces on which the electron source ELS and the phosphor layer PH are formed are opposed to each other. (Not shown)
A spacer planting structure is provided which is joined between the rear panel PNL1 and the front panel PNL2 and includes a spacer SPC and an adhesive layer FGS for maintaining the distance between the panels at a predetermined value. In order to ensure this conductive connection, a conductive film EEF is interposed between the spacer SPC and the adhesive layer FGS.

The spacer SPC is formed by the core glass CRG and the conductive film SRG having a high resistance layer that covers the surface of the core glass CRG. The spacer SPC is planted between the rear panel PNL1 and the front panel PNL2 and bonded by the adhesive layer FRG. is doing. The material of the core glass CRG is aluminosilicate glass or soda glass, and the material of the conductive film SRG is Cr ₂ O ₃ or Nb ₂ O ₅ .

That is, the electron emission type FPD includes a back panel PNL1 formed of the back substrate SUB1 provided with the electron source ELS as described above, a phosphor layer PH, and electrons e emitted from the electron source ELS to the phosphor layer PH. ^The front panel PNL2 composed of the front substrate SUB2 having the anode AD formed with an acceleration voltage for projecting the-is bonded together, and the internal spaces facing both panels are sealed to a predetermined reduced pressure or vacuum state. . The back substrate SUB1 constituting the back panel PNL1 has a large number of electron sources ELS arranged in a matrix, and the front substrate SUB2 constituting the front panel PNL2 contains the phosphor layer PH and the electrons e ⁻ emitted from the electron source ELS. It has an anode AD that forms an acceleration voltage for forming an electric field that strikes the phosphor layer PH.

  Each electron source is paired with a corresponding phosphor layer to constitute a unit pixel. Usually, one pixel (color pixel, pixel) is composed of unit pixels of three colors of red (R), green (G), and blue (B). In the case of a color pixel, the unit pixel is also called a sub-pixel (sub-pixel).

  Regarding the distance between the back substrate SUB1 and the front substrate SUB2, see, for example, Patent Document 1 regarding the spacer SPC that is a space holding member arranged to support both substrates in the display area.

  For example, in a display device using a metal film-insulating film-metal film (MIM) electron source as a thin film electron source, the distance between the electron source ELS (cathode) and the anode AD (anode) is about 1 mm to 5 mm, A high voltage having a potential difference of 3 kV to 10 kV is applied. For this reason, electric charges are charged in the insulator spacer that bridges between the two substrates and maintains a predetermined distance, and discharge occurs, leading to destruction of the cathode and other structural parts. In order to avoid this, the spacer planting structure composed of the spacer SPC and the bonding adhesive layer FGS needs to have a certain degree of conductivity in order to release the charge.

As an example of such a spacer planting structure, a conductive spacer in which a conductive member is formed on a blue glass surface is used, and a conductive glass filler is added and dispersed in an inorganic adhesive between the back substrate and the front substrate. An adhesive that adheres with an adhesive is disclosed in Patent Document 2. Also, there is an attempt to obtain a reliable conductive connection between the back substrate and the front substrate by interposing a conductive film EEF (see FIG. 6) between the spacer having the high resistance film coated on the core glass and the adhesive. This is disclosed in Patent Document 3. Patent Document 3 discloses that a high-resistance film to be coated is preferably a transition metal and a ceramic composite.
JP 2003-317648 A JP 2000-57937 A JP 2000-82424 A

  In the conventional spacer planting structure, when a conductive spacer having a conductive member formed on the surface thereof is bonded with an inorganic adhesive, it is easy to peel between the inorganic adhesive and the spacer. In addition, in the case of interposing a conductive film that ensures conductive connection between the back substrate and the front substrate, peeling is likely to occur at the interface between the conductive film and the adhesive layer of the glass frit. As a result, the reliability of the display device decreases.

  An object of the present invention is to provide a conductive connection between the spacer and the rear substrate and the front substrate without interposing a conductive film, and to prevent peeling at the interface between the spacer and the adhesive layer, thereby achieving high reliability. A spacer planting structure and a display device using the spacer planting structure are obtained.

About the spacer planting structure of the present invention,
The spacer of the present invention for bonding and planting with an adhesive layer between the opposing surfaces of the first substrate and the second substrate and maintaining the gap between the two at a predetermined value is the core glass, and the core glass The adhesive layer that is formed of a coated glass that covers the surface and directly joins the spacer between the first substrate and the second substrate is the same glass as the coated glass.

Moreover, in the spacer planting structure of the present invention,
The coated glass and the adhesive layer were vanadium-based glasses containing vanadium as a main component and tellurium and phosphorus as additives in different weight ratios.

Moreover, in the spacer planting structure of the present invention,
The tellurium and phosphorus diffused each other between the adhesive layer and the coated glass to have a diffusion layer showing a weight ratio different from the original weight ratio.

Moreover, in the spacer planting structure of the present invention,
The tellurium concentration in the adhesive layer was higher than that of the coated glass, and the phosphorus concentration in the adhesive layer was lower than that of the coated glass.

  In the spacer planting structure of the present invention, a conductive filler can be mixed into the adhesive layer.

  The display device of the present invention includes an insulating substrate, and a plurality of scanning lines provided on the main surface of the insulating substrate, extending in the first direction and juxtaposed in the second direction intersecting the first direction, A plurality of signal lines extending in the second direction and arranged in parallel in the first direction; a back panel having an electron source provided in the vicinity of an intersection of the scanning lines and the signal lines; and a transparent insulating substrate; A front panel having a phosphor layer provided on the main surface of the transparent insulating substrate and paired with each of the electron sources, an anode, and the back panel facing the main surfaces at a predetermined interval; A sealing frame that forms a decompression container together with the two panels, and a spacer that holds the predetermined distance between the rear panel and the front panel;

  In this invention, the said spacer is comprised with the core glass and the coat glass which coat | covered the surface of this core glass. And it is characterized by making it the spacer planting structure which made the glass similar to the said coating glass the contact bonding layer which adhere | attaches the said spacer directly between the said back panel and the said front panel.

  Further, in the display device of the present invention, the coated glass and the adhesive layer are vanadium-based glasses containing vanadium as a main component and tellurium and phosphorus at different weight ratios as additives, and between the adhesive layer and the coated glass. In addition, the tellurium and phosphorus may diffuse each other to have a diffusion layer exhibiting a weight ratio different from the original weight ratio.

  In the display device of the present invention, the tellurium and phosphorus diffuse between each other between the adhesive layer and the coat glass to have a diffusion layer having a weight ratio different from the original weight ratio.

  In the display device of the present invention, the tellurium concentration in the adhesive layer is higher than that of the coated glass, and the phosphorus concentration in the adhesive layer is lower than that of the coated glass. The melting of the coated glass can be prevented.

  In the display device of the present invention, a conductive filler can be mixed in the adhesive layer.

  The adhesion between the back panel and the front panel and the spacer is improved. In particular, the adhesive force is greatly improved by forming a diffusion layer between the coated glass and the adhesive layer. Since the conductive filler does not diffuse, the resistance value of the adhesive layer is maintained and the charge discharging function is not deteriorated.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS The best mode for carrying out the present invention will be described below in detail with reference to the drawings of the examples.

FIG. 1 is a schematic cross-sectional view for explaining the basic structure of a spacer planting structure of the present invention and a display device using the spacer planting structure. This display device is an electron emission display device using a metal film-insulating film-metal film type electron source as an electron source. Similar to FIG. 6, this display device is provided on the main surface of the back substrate SUB1, which is the first substrate, and is arranged in parallel in the second direction that extends in the first direction and intersects the first direction. A plurality of scanning lines GL, a plurality of signal lines CL provided below the scanning lines GL, extending in the second direction and arranged in parallel in the first direction, and in the vicinity of the intersection of the scanning lines GL and the signal lines CL A back panel PNL1 having an electron source provided;
A front substrate SUB2 that is a second substrate, a front panel PNL2 that is provided on the main surface of the front substrate SUB2 and has a phosphor layer PH that forms a pair with each of the electron sources ELS, and an anode AD;
A sealing frame that forms a decompression container together with both panels by inserting the main surfaces, that is, the inner surfaces of the rear panel PNL1 and the front panel PNL2 facing each other, where the inner surfaces on which the electron source ELS and the phosphor layer PH are formed are opposed to each other. (Not shown)
A spacer planting structure is provided which is joined between the rear panel PNL1 and the front panel PNL2 and includes a spacer SPC and an adhesive layer FGS for maintaining the distance between the panels at a predetermined value.

  The spacer SPC constituting the spacer planting structure is formed of a core glass CRG and a coated glass SRG having a high resistance layer covering the surface of the core glass CRG, and is planted between the rear panel PNL1 and the front panel PNL2. It is made to stand and bonded with the adhesive layer FRG. The material of the core glass CRG is aluminosilicate glass or soda glass, and the material of the high resistance coated glass SRG is vanadium phosphorus glass. Other configurations are the same as those shown in FIG.

That is, the electron emission type FPD includes a back panel PNL1 formed of the back substrate SUB1 provided with the electron source ELS as described above, a phosphor layer PH, and electrons e emitted from the electron source ELS to the phosphor layer PH. ^The front panel PNL2 composed of the front substrate SUB2 having the anode AD formed with an acceleration voltage for projecting the-is bonded together, and the internal spaces facing both panels are sealed to a predetermined reduced pressure or vacuum state. . The back substrate SUB1 constituting the back panel PNL1 has a large number of electron sources ELS arranged in a matrix, and the front substrate SUB2 constituting the front panel PNL2 contains the phosphor PH layer and the electrons e ⁻ emitted from the electron source ELS. It has an anode AD that forms an acceleration voltage for forming an electric field that strikes the phosphor layer PH.

  In the spacer planting structure of Example 1, a spacer SPC composed of a core glass CRG and a high-resistance layer coated glass SRG covering the surface of the core glass CRG is directly bonded to the rear panel PNL1 and the front panel PNL2 with an adhesive layer FGS. It is planted by joining with.

In the spacer planting structure of Example 1, the coated glass SRG and the adhesive layer FGS are mainly composed of vanadium (for example, V ₂ O ₅ ), and tellurium (Te) and phosphorus (P) are added in different weight ratios as additives. In this case, tellurium and phosphorus are diffused between the adhesive layer FGS and the coated glass SRG by heating during bonding, and a diffusion layer having a weight ratio different from the original weight ratio is formed.

  Further, in the spacer planting structure of Example 1, the tellurium concentration in the adhesive layer FGS is higher than that of the coated glass SRG, and the phosphorus concentration in the adhesive layer FGS is lower than that of the coated glass SRG. Thus, melting of the coated glass SRG at the time of bonding can be prevented.

  In addition, in the spacer planting structure of Example 1, a conductive filler can be mixed into the adhesive layer FGS to obtain a predetermined resistance value.

By using the spacer planting structure of the present embodiment, the adhesion between the back panel and the front panel and the spacer is improved. In particular, the adhesive force is greatly improved by forming a diffusion layer between the coated glass and the adhesive layer. Since the filler does not diffuse, the resistance value of the adhesive layer is maintained, the charge discharging function is not deteriorated, and a highly reliable display device can be provided.
Hereinafter, the material used in order to acquire the said effect is demonstrated.

The glass for coating was composed mainly of V ₂ O ₅ ; 40 to 50 wt% and P ₂ O ₅ ; 25 to 30 wt% in terms of oxide. Specific examples are as follows. The Te compound was not added. Further, no metal layer or the like for the electrode was formed on the spacer.

When the above glass for coating is used, the effect of improving the adhesion can be obtained compared to the conventional product.

The cathode-side adhesive layer was composed mainly of V ₂ O ₅ ; 50 to 65 wt% and P ₂ O ₅ ; 25 wt% in terms of oxide. TeO ₂ ; 5 wt% was added to the cathode side adhesive layer. Examples used as the cathode side adhesive layer are shown in Table 2 below. By using the adhesive layer on the cathode side, the effect of improving the adhesion can be obtained compared to the conventional product.

The anode side adhesive layer used was composed mainly of V ₂ O ₅ ; 60 to 65 wt% and P ₂ O ₅ ; 20 to 25 wt% in terms of oxide. Te was not added to the anode side adhesive layer. Further, a conductive filler was added to the anode side adhesive layer, and the transition point / pour point was set higher than that of the cathode side. The reason is that the spacer is bonded to the anode side substrate and then bonded to the cathode side, so that it is easier to make it vertical compared to the case where both sides are bonded simultaneously. The addition amount of the conductive filler was 10 to 30 wt% with respect to 90 to 70 wt% of the glass.
By using the adhesive layer on the anode side, the effect of improving the adhesion can be obtained compared to the conventional product.

  A display device was prepared by combining the above coat layer and adhesive layer.

  The coated glass was made into a slurry and attached using a printing method. The adhesive glass was made into a paste and used by the dip method. A metal thin film or the like is not provided between the coat layer and the adhesive layer. As a result, a diffusion layer was formed between the adhesive layer and the coat layer. In order to increase the diffusion layer, it is particularly preferable to increase the firing time. When the diffusion layer was observed, an inclined concentration distribution was formed in P, Te, and V. By having the concentration distribution of the glass of each composition, the difference in characteristics such as the thermal expansion coefficient and the glass transition point is alleviated, and the effect of improving the adhesion is obtained as compared with the conventional product. Furthermore, since the diffusion layer does not cause stress concentration on a specific part and bonding with excellent durability can be achieved, a flat display device with high durability can be provided.

  When the above compositions were confirmed, the most desirable combination was 1-L for the coating layer, 2-A for the anode side, and 3-B for the cathode side adhesive layer. By combining these, the effect of improving the adhesion can be obtained as compared with other display devices.

  FIG. 2 is a diagram illustrating an example of the overall configuration of a display device according to the present invention. 2A is a perspective view, and FIG. 2B is a schematic cross-sectional view taken along the line A-A ′ of FIG. In FIG. 2, a signal line (data line, cathode electrode line) CL and a scanning line (gate electrode line) GL are provided on the inner surface of the rear substrate SUB1 constituting the rear panel PNL1, and the signal line CL and the scanning line GL intersect each other. An electron source ELS is formed in the portion. A scanning line lead line (not shown) is formed at the end of the scanning line GL, and a signal line lead line (not shown) is formed at the end of the signal line CL.

  A light shielding film (black matrix) BM, an anode (metal back, anode) AD, a phosphor layer PH, and the like are formed on the inner surface of the front substrate SUB2 constituting the front panel PNL2. The rear substrate SUB1 constituting the rear panel PNL1 and the front substrate SUB2 constituting the front panel PNL2 are bonded to each other by a sealing member FGM with a sealing frame (frame glass) MFL interposed therebetween. In order to maintain the bonded gap at a predetermined value, the above-described spacer planting structure is installed between the back substrate SUB1 and the front substrate PNL2.

  The internal space sealed by the back panel PNL1, the front panel PNL2, and the sealing frame MFL is exhausted from an exhaust pipe (not shown) provided in a part of the back panel PNL1, and is maintained in a predetermined vacuum state.

  FIG. 3 is a schematic diagram for explaining a detailed structure of a cross section taken along the line A-A ′ of FIG. 1. 4 is an enlarged cross-sectional view of the main part of FIG. 3 and 4, the rear substrate SUB1 constituting the rear panel PNL1 and the front substrate SUB2 constituting the front panel PNL2 are integrated via a frame glass MFL installed on the periphery. The same reference numerals as those in FIG. 2 correspond to the same functional parts. The frame glass MFL, the rear substrate SUB1, and the front substrate SUB2 are fixed by a sealing member FGM, for example, with a gap of about 3 mm. In the display area, the spacer SPC that holds a feeling between the back substrate SUB1 and the front substrate SUB2 is fixed by an adhesive layer FGS that is a conductive bonding material.

  The spacer SPC that constitutes the spacer planting structure is based on the structure as described above and is made of the material described in the above embodiment. The adhesive layer FGS to which the spacer SPC is bonded may contain a thermal expansion coefficient adjusting filler. This filler is preferably conductive.

  FIG. 5 is a diagram illustrating an example of an equivalent circuit of the display device of the present invention. A region indicated by a broken line in FIG. 5 is a display region AR. In this display region AR, n signal lines CL and m scanning lines GL are arranged so as to intersect with each other to form an n × m matrix. ing. Each intersection of the matrix constitutes a sub-pixel (unit pixel, sub-pixel), and one group of three sub-pixels “R”, “G”, “B” in the figure constitutes one color pixel (color pixel). To do. The signal line CL is connected to the image signal drive circuit DDR at the signal line lead terminal CLT, and the scan line GL is connected to the scan signal drive circuit SDR at the scan line lead terminal GLT. The image signal NS is input from the external signal source to the image signal driving circuit DDR, and the scanning signal SS is similarly input to the scanning signal driving circuit SDR.

  Accordingly, a two-dimensional full-color image can be displayed by supplying an image signal to the signal line CL that intersects the scanning lines GL that are sequentially selected. By using the image display panel of this configuration example, a self-luminous flat display device with relatively low voltage and high efficiency is realized.

  In the display device according to the present invention, by setting the spacer described in the above-described embodiment between the back substrate and the front substrate, the charge to be charged up to the spacer is discharged (absorbed) to the substrate side, A display device capable of displaying a quality image can be provided.

  In the above embodiment, the structure using the MIM type as the electron source has been described as an example. However, the present invention is not limited to this, and the self-luminous display device using the various electron sources described above. Needless to say, it can be applied.

It is a schematic cross section explaining the basic structure of the spacer planting structure of the present invention and a display device using the spacer planting structure. It is a figure explaining the example of whole structure of the display apparatus by this invention. It is a schematic diagram explaining the detailed structure of the cross section along the A-A 'line of FIG. It is a principal part expanded sectional view of FIG. It is a figure explaining the example of an equivalent circuit of the display apparatus of this invention. 1 is a schematic cross-sectional view illustrating a basic configuration of an electron emission display device using a metal film-insulating film-metal film type electron source as an electron source.

Explanation of symbols

PNL1 ... Back panel, SUB1 ... Back substrate, PNL2 ... Front panel, SUB2 ... Front substrate, SPC ... Spacer, GL ... Scan line, CL ... Signal line, ELS -Electron source, AD ... anode, BM ... black matrix, PH ... phosphor layer, SDR ... scanning signal line drive circuit, DDR ... image signal line drive circuit.

Claims (11)

A spacer for bonding and planting between the opposing surfaces of the first substrate and the second substrate with an adhesive layer, and maintaining a gap between the two at a predetermined value, and an adhesive layer for planting by bonding the spacer A spacer planting structure comprising:
The spacer is formed of a core glass and a coated glass covering the surface of the core glass,
A spacer planting structure characterized in that the adhesive layer for directly joining the spacer between the first substrate and the second substrate is made of a glass similar to the coat glass. A spacer for bonding and planting between the opposing surfaces of the first substrate and the second substrate with an adhesive layer, and maintaining a gap between the two at a predetermined value, and an adhesive layer for planting by bonding the spacer A spacer planting structure comprising:
The spacer is formed of a core glass and a coated glass covering the surface of the core glass,
A spacer planting structure characterized in that the coated glass and the adhesive layer are glass containing vanadium as a main component and tellurium and phosphorus as additives. In claim 2,
A spacer planting structure characterized in that the tellurium and phosphorus diffuse between each other between the adhesive layer and the coated glass, and have a diffusion layer showing a weight ratio of the tellurium and phosphorus different from the adhesive layer or the coated glass. body. In claim 3,
The spacer planting structure characterized in that the tellurium concentration in the adhesive layer is higher than the tellurium concentration in the coated glass, and the phosphorous concentration in the adhesive layer is lower than the phosphorous concentration in the coated glass. . In claim 2,
A spacer planting structure characterized in that the Te and P concentrations of the adhesive layer on the back substrate side and the adhesive layer on the front substrate side are different. In any one of Claims 1 thru | or 5,
A spacer planting structure characterized in that a conductive filler is mixed in the adhesive layer. An insulating substrate, a plurality of scanning lines provided on a main surface of the insulating substrate, extending in the first direction and juxtaposed in a second direction intersecting the first direction, and extending in the second direction A back panel having a plurality of signal lines arranged in parallel in the first direction, and an electron source provided in the vicinity of an intersection of the scanning lines and the signal lines;
A front panel having a transparent insulating substrate, a phosphor layer provided on the main surface of the transparent insulating substrate and paired with each of the electron sources, and an anode;
A sealing frame that forms a decompression container together with both panels, inserted between the back panel and the inner periphery of the end of the front panel with the main surfaces facing each other;
A spacer planting structure comprising a spacer and an adhesive layer bonded between the back panel and the front panel and maintaining a distance between the panels at a predetermined value,
The spacer is formed of a core glass and a coated glass covering the surface of the core glass,
The display device, wherein the adhesive layer that directly joins the spacer between the back panel and the front panel is made of glass similar to the coated glass. In claim 7,
The coat glass and the adhesive layer contain vanadium, tellurium and phosphorus, respectively. In claim 8,
A display device comprising a diffusion layer between the adhesive layer and the coated glass, wherein the diffusion layer has a tellurium and phosphorus content different from that of the adhesive layer or the coated glass. In claim 8,
The display device, wherein the tellurium concentration of the adhesive layer is higher than the tellurium concentration of the coated glass, and the phosphorus concentration of the adhesive layer is lower than the phosphorous concentration of the coated glass. In any of claims 7 to 10,
A display device, wherein a conductive filler is mixed in the adhesive layer.

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