JPWO2012132652A1 - Paste and flat panel display manufacturing method - Google Patents

Abstract

The present invention provides a paste capable of forming a partition wall with less residual organic matter, and a highly reliable flat display panel including the partition wall.
A paste containing a low softening point glass powder having a softening point of 570 to 620 ° C. and an organic component, wherein the silicon oxide content in the low softening point glass powder is oxidized by X (SiO ₂ ) (mol%) oxidation. The boron content is X (B ₂ O ₃ ) (mol%), the alkali metal oxide content is X (M ₂ O) (mol%), and the alkaline earth metal oxide content is X (MO) (mol%). ), A paste satisfying the following formulas (1) to (3) is provided when the zinc oxide content is X (ZnO) (mol%).
A = X (SiO ₂ ) + X (B ₂ O ₃ ) −X (M ₂ O) (1)
B = X (ZnO) (2)
C = X (M ₂ O) + X (MO) + X (ZnO) (3)

Description

  The present invention relates to a paste used for forming an insulating pattern and a method for manufacturing a flat display panel using the paste.

  In recent years, development of flat displays such as plasma display panels, field emission displays, fluorescent display tubes, liquid crystal display devices, electroluminescence displays, and light emitting diodes has been rapidly advanced. Among these, the plasma display generates plasma discharge between the anode electrode and the cathode electrode facing each other in the discharge space provided between the front glass substrate and the rear glass substrate, and is enclosed in the discharge space. Display is performed by irradiating phosphors provided in the discharge space with ultraviolet rays generated from gas. A gas discharge type display such as a plasma display or a fluorescent display tube requires an insulating partition for partitioning a discharge space. A field emission display such as a field emission display requires an insulating partition for isolating the gate electrode from the cathode.

  As a method of forming these barrier ribs, barrier rib paste is repeatedly applied in a pattern by a screen printing plate, dried and then screen printed by baking, masked with a resist on the dried barrier rib material layer, and sandblasted. After shaving, sand blasting method for firing, baking the dried partition material, masking with a resist on the layer, etching method for etching, pressing a mold having a pattern on the coating film of partition paste After the pattern is formed, a mold transfer method (imprint method) in which baking is performed, a partition material made of a photosensitive paste material is applied, dried, exposed and developed, and then subjected to a photosensitive paste method (photo) Lithography method) is known. Each of these pattern formation methods is provided with a paste coating film patterned using a paste containing a low softening point glass and an organic component, and the organic component is removed by baking to form an insulating pattern containing a low softening point glass. This is a method of forming a partition wall. Among them, the photosensitive paste method is a method that can cope with an increase in area with high definition and a high cost merit.

  In the conventional forming method, a pattern is formed using a paste containing a low softening point glass and an organic component, and then fired to form partition walls, so that the organic component remains slightly after firing. When this residual organic component is present in a large amount, the partition walls are colored, and there is a problem that the display characteristics of the display such as the light emission efficiency and color purity of the panel are affected. Furthermore, in the plasma display, the organic component remaining in the barrier ribs is generated as a gas in the sealing process in which the front plate and the rear plate are bonded to form a panel, which affects the front plate protective layer and increases the discharge voltage. There is a problem that the reliability of the panel cannot be improved due to the deterioration of the characteristics of the panel and the impurity gas remaining in the panel.

  Therefore, various methods for reducing the residual organic components after firing have been proposed in order to produce a display having excellent display characteristics such as luminance and color purity and high panel reliability (see Patent Documents 1 to 3). Patent Document 1 is characterized in that a resin containing a hydroxyl group and a polymerizable unsaturated group is used as an organic component in the paste, for example, a polyol having excellent thermal decomposability at high temperatures. Patent Document 2 is characterized in that an acrylic copolymer having a polyalkylene oxide segment having a high oxygen atom content is used as the organic component in order to increase the thermal decomposability of the organic component. Patent Document 3 is characterized by the use of a low softening point glass having a glass transition point that is 10 ° C. higher than the temperature at which the weight loss rate of the organic component reaches 80% so that the decomposition product of the organic component does not remain in the glass. is there. However, these methods can reduce residual organic components due to poor thermal decomposability, but cannot suppress thermal decomposition products due to adsorption to glass, so the reduction of residual organic components in the partition is still insufficient. There was a problem.

JP 2001-305729 A JP 2008-50594 A JP-A-11-52561

  Therefore, the present invention pays attention to the above-mentioned problems of the prior art, and provides a paste capable of forming a partition wall that has good thermal decomposability of organic components during firing, suppresses adsorption of pyrolyzed products to glass, and has few remaining organic components. The purpose is to do. Another object of the present invention is to provide a flat display panel that is formed with a partition wall having a small amount of residual organic components, has excellent display characteristics such as luminance and color purity, and has high reliability.

In order to solve the above problems, the present invention has the following configuration.
(1) A low softening point glass powder having a softening point of 570 to 620 ° C. and an organic component, wherein the low softening point glass powder contains silicon oxide, boron oxide, alkali metal oxide, alkaline earth metal oxide, and zinc oxide. And the silicon oxide content in the low softening point glass powder is X (SiO ₂ ) (mol%), and the boron oxide content in the low softening point glass powder is X (B ₂ O ₃ ) (mol%). The alkali metal oxide content in the low softening point glass powder is X (M ₂ O) (mol%), and the alkaline earth metal oxide content in the low softening point glass powder is X (MO) (mol). %), When the zinc oxide content in the low softening point glass powder is X (ZnO) (mol%), the value of A represented by the following formula (1) is in the range of 35 to 46, And the value of B represented by following formula (2) is 1.5-5. Of in the range, and paste the values of C represented by the following formula (3) is being in the range of 24-30.

A = X (SiO ₂ ) + X (B ₂ O ₃ ) −X (M ₂ O) (1)
B = X (ZnO) (2)
C = X (M ₂ O) + X (MO) + X (ZnO) (3)
(2) The paste as described in (1) above, wherein the organic component contains a photosensitive organic component.
(3) A method for producing a flat display panel, wherein the paste according to any one of (1) to (2) above is applied onto a substrate and baked to form an insulating pattern.
(4) A method for producing a flat display panel, comprising applying a paste according to (2) above on a substrate, exposing, developing, and baking to form an insulating pattern.
(5) A flat display panel having a partition mainly composed of a low softening point glass having a softening point of 570 to 620 ° C., wherein the low softening point glass powder is silicon oxide, boron oxide, alkali metal oxide, alkaline earth A metal oxide and zinc oxide, the silicon oxide content in the low softening point glass powder is X (SiO ₂ ) (mol%), and the boron oxide content in the low softening point glass powder is X (B ₂ O ₃ ) (mol%), the alkali metal oxide content in the low softening point glass powder is X (M ₂ O) (mol%), the alkaline earth metal oxide content in the low softening point glass powder When the rate is X (MO) (mol%) and the zinc oxide content in the low softening point glass powder is X (ZnO) (mol%), the value of A represented by the following formula (1) is 35. ˜46 and the following formula (2 The value of B represented by the formula is in the range of 1.5 to 5.5, and the value of C represented by the following formula (3) is in the range of 24 to 30. Display panel.

A = X (SiO ₂ ) + X (B ₂ O ₃ ) −X (M ₂ O) (1)
B = X (ZnO) (2)
C = X (M ₂ O) + X (MO) + X (ZnO) (3)

  ADVANTAGE OF THE INVENTION According to this invention, the paste which can form an insulating pattern with few residual organic components can be provided. In addition, an insulating pattern with a small amount of residual organic components can be formed, and a display panel having excellent display characteristics such as luminance and color purity and high reliability can be stably provided.

  The paste referred to in the present invention includes an inorganic component capable of pattern formation by a method such as a screen printing method, a sand blast method, an etching method, a mold transfer method (imprint method), and a photosensitive paste method (photolithography method). It is a mixture of organic components. When used for forming a high-definition insulating pattern such as a partition wall of a plasma display, a photosensitive paste containing a photosensitive organic component as an organic component is preferable.

  The paste of the present invention contains a low softening point glass powder having a softening point of 570 to 620 ° C. as an essential component as an inorganic component. The low softening point glass powder having a softening point of 570 to 620 ° C. is the main component of the partition wall, and is baked at a temperature near the softening point of the low softening point glass powder to remove the organic components described later, thereby reducing the low softening point glass. A pattern comprising an inorganic component can be obtained.

  The low softening point glass powder in this invention refers to the glass powder whose softening point is the range of 570-620 degreeC. When the softening point is in this range, there is no deformation of the pattern during sintering, and the meltability is also appropriate. In particular, when an insulating pattern is formed on a glass substrate, it is sufficiently softened even when sintered at a relatively low temperature so that problems such as distortion of the substrate do not occur. A pattern can be obtained. The softening point is preferably in the range of 575 to 597 ° C, more preferably in the range of 580 to 595 ° C.

  The softening point as used in the present invention can usually be measured using a differential thermal analyzer (DTA). For example, from the DTA curve obtained by measuring glass powder, the endothermic end temperature at the endothermic peak is determined by the tangent method. It can be obtained by extrapolation.

  When the paste of the present invention is a photosensitive paste, the refractive index of the low softening point glass powder is preferably 1.45 to 1.65. By matching the refractive indexes of the inorganic component and the organic component and suppressing light scattering, highly accurate pattern processing becomes easy. The refractive index in the present invention can be measured by the Becke line detection method, and the refractive index at a wavelength of 436 nm (g-ray of a mercury lamp) at 25 ° C. is defined as the refractive index in the present invention.

The particle size of the low softening point glass powder used in the paste of the present invention is selected in consideration of the shape of the pattern to be produced, but the 50% particle size (average particle size) d ₅₀ in the weight distribution curve is 0.1. It is preferable that the maximum particle diameter d _max is 20 μm or less.

The low softening point glass powder used in the paste of the present invention must contain silicon oxide, boron oxide, and alkali metal oxide in terms of oxides as constituent components. Furthermore, the silicon oxide content in the low softening point glass powder is X (SiO ₂ ) (mol%), the boron oxide content in the low softening point glass powder is X (B ₂ O ₃ ) (mol%), and the softening is low. When the alkali metal oxide content in the point glass powder is X (M ₂ O) (mol%), it is essential that the value of A represented by the following formula (1) is in the range of 35 to 46. It is.

A = X (SiO ₂ ) + X (B ₂ O ₃ ) −X (M ₂ O) (1)
In general, the alkali metal refers to lithium, sodium, potassium, rubidium, and cesium. The alkali metal oxide contained as a constituent of the low softening point glass powder of the present invention includes lithium oxide, sodium oxide, and potassium oxide. It is necessary to include one or more of these as essential components, and the total content of lithium oxide, sodium oxide, and potassium oxide to be X (M ₂ O) and satisfy the above formula (1).

  By setting A to 46 or less, the remaining organic components can be reduced. On the other hand, when A is small, the content of the alkali metal oxide is increased, and the partition wall is yellowed after firing. Preferably it exists in the range of 36-45, More preferably, it exists in the range of 38-44.

  In the present invention, it is not clear why the remarkable effect that a partition wall with a small amount of residual organic component can be formed by setting A in the above formula (1) to 46 or less, but the following mechanism is conceivable.

  Silicon oxide and boron oxide are acidic components, alkali metal oxides are basic components, and A in the above formula (1) is an index indicating the balance between acidic components and basic components in the glass powder. When the alkali metal oxide content is small and A is greater than 46, the acid-base balance of the glass is biased, making it chemically unstable, reacting with organic components in the paste, and adsorbing thermal decomposition products. As a result, residual organic components increase. By increasing the alkali metal oxide, which is a basic component, and setting A to 46 or less, the acid-base balance of the glass is improved. As a result, it becomes chemically stable and the reaction with the organic component in the paste is suppressed. It is presumed that the adsorption of the pyrolyzate is suppressed and the remaining organic components can be reduced.

  Each component constituting the low softening point glass powder will be described below.

  Silicon oxide is a material that forms a glass skeleton. It is effective in improving the denseness, strength and stability of glass, and is effective in reducing the refractive index of glass. In addition, when a glass substrate is used as the base material, the thermal expansion coefficient can be controlled to prevent problems such as peeling due to mismatch with the glass substrate. As for the compounding rate of a silicon oxide, 10-40 mol% is preferable, More preferably, it is 20-40 mol%. By setting it to 10 mol% or more, it is possible to suppress the thermal expansion coefficient to be small, to make it difficult for cracks to occur when baked on a glass substrate, and to keep the refractive index low. Moreover, by setting it as 40 mol% or less, a softening point can be restrained low and the baking temperature to a glass substrate can be made low.

  Boron oxide is a material that forms a glass skeleton. It has the effect of lowering the softening point and is effective for lowering the refractive index. The compounding ratio of boron oxide is preferably 20 to 45 mol%, more preferably 20 to 40 mol%. By setting it as 20 mol% or more, the softening point can be kept low, baking onto the glass substrate can be facilitated, and the refractive index can be kept low. Moreover, the chemical stability of glass can be maintained by setting it as 45 mol% or less.

  Lithium oxide, sodium oxide and potassium oxide, which are alkali metal oxides, have an effect of not only facilitating control of the thermal expansion coefficient of glass but also lowering the softening point. 10-30 mol% is preferable and, as for the total of the compounding ratio of an alkali metal oxide, More preferably, it is 10-20 mol%. By making it 10 mol% or more, the effect of lowering the softening point of the glass can be obtained. Moreover, chemical stability can be maintained by setting it as 30 mol% or less, a thermal expansion coefficient can be restrained small, and a refractive index can be restrained low. As the alkali metal, it is preferable to select lithium because yellowing due to migration of silver ions can be reduced.

  As the low softening point glass powder in the present invention, it is essential to further contain 1.5 to 5.5 mol% of zinc oxide in terms of oxide as a constituent component. Since zinc oxide has the effect of lowering the softening point without greatly changing the thermal expansion coefficient of the glass, it is necessary to contain 1.5 mol% or more. Further, when the content is increased, the stability of the glass is lowered, the refractive index is increased, the reactivity with the organic component in the paste is increased, and the paste viscosity is likely to increase with time, so that 5.5 mol. It is necessary to mix | blend in the range below%. Preferably it is 2.5-3.3 mol%.

  As a low softening point glass powder in the present invention, as a constituent component, it further contains an alkaline earth metal oxide in oxide notation, and the total of the alkali metal oxide, alkaline earth metal oxide and zinc oxide is 24 to It is essential to be 30 mol%.

  In general, alkaline earth metal oxides refer to calcium oxide, strontium oxide, barium oxide, and radium oxide. In the present invention, alkaline earth metal oxides include magnesium oxide, calcium oxide, strontium oxide, and barium oxide. Yes, including an alkaline earth metal oxide means containing one or more of these, and the total of these contents is used as the content of the alkaline earth metal oxide.

  Alkali metal oxides, alkaline earth metal oxides, and zinc oxides all have the effect of lowering the softening point, and therefore the total amount thereof must be 24 mol% or more. Moreover, since a refractive index will become high if content rate becomes high, it is necessary to mix | blend the sum total in the range of 30 mol% or less. Preferably it is 25-29 mol%, More preferably, it is 26-28 mol%.

  Alkaline earth metal oxides are effective in adjusting the thermal expansion coefficient and have the effect of lowering the softening point. The blending ratio of the alkaline earth metal oxide is preferably 2 to 20 mol%, more preferably 3 to 18 mol%. By making it 2 mol% or more, the effect of lowering the softening point of the glass can be obtained. Moreover, the chemical stability of glass can be maintained and refractive index can be restrained low by setting it as 20 mol% or less.

  As other components, it may contain aluminum oxide, titanium oxide, zirconium oxide or the like which has an effect of improving the chemical stability of glass, or bismuth oxide or lead oxide which has an effect of lowering the softening point. good.

  As a method for producing the low softening point glass powder, for example, raw materials such as lithium oxide, silicon oxide, boron oxide, barium oxide, magnesium oxide and aluminum oxide, which are constituent components, are mixed so as to have a predetermined composition, and 900 to After melting at 1200 ° C., it is cooled, made into a glass frit, pulverized and classified to a fine powder of 20 μm or less. High purity carbonates, oxides, hydroxides and the like can be used as raw materials. Depending on the type and composition of the glass powder, it is possible to use ultra-pure alkoxides of 99.99% or more and organic metal raw materials, and use powders that are homogeneously produced by the sol-gel method. This is preferable because a small and high-purity fired film can be obtained.

  In the present invention, the constituent components of the low softening point glass powder and the content thereof can be calculated from the raw materials at the time of glass powder production and the blending ratio thereof, but can also be calculated from the glass powder, paste, or partition. In the case of glass powder, it can be quantitatively determined by performing atomic absorption analysis and inductively coupled plasma (ICP) emission spectroscopic analysis. In the case of a partition wall, it can be quantitatively determined by Auger electron spectroscopy. Specifically, the low softening point glass is distinguished by the difference in density of the SEM image of the partition wall cross section, and elemental analysis is performed by Auger electron spectroscopy. In addition, other known analysis means such as selectively cutting out the low softening point glass from the partition wall and performing atomic absorption analysis or inductively coupled plasma (ICP) emission spectroscopic analysis can be used supplementarily. In the case of a paste, it can be analyzed by the same technique as that for glass powder by isolating the glass powder by operations such as filtration and washing. Or it can analyze by the method similar to a partition by apply | coating and baking a paste and forming a partition.

The calculation method of the content rate of a component from an elemental analysis result is as follows. In elemental analysis, information on the mass ratio of the elements contained in the glass powder is obtained, so based on the atomic weight, the formula weight of the oxide, the number of cations in the oxide composition formula, the mass ratio in terms of oxide, That is, the mass ratio of the constituent components can be calculated. Conversion to the molar ratio of the mass ratio of the obtained structural component can be performed by the following formula when Ri: mass% of structural component i, Fi: formula weight of structural component i, and Σ: sum of all components.
(Ri / Fi) / Σ (Ri / Fi) × 100 (mol%)
In the present invention, it is preferable to add a filler as an inorganic component. The filler in the present invention is added to improve the strength of the partition wall, and refers to an inorganic powder that hardly melts and flows even at the firing temperature. Specifically, it refers to an inorganic powder that does not have a softening point, a melting point, or a decomposition temperature at 650 ° C. or lower and exists as a solid at 650 ° C. As a filler, at least 1 sort (s) chosen from ceramic powder, such as a high softening point glass powder whose softening point is 650-1200 degreeC, and cordierite, an alumina, a silica, a magnesia, a zirconia, can be used. Using a 50% particle size (average particle diameter) d ₅₀ and the average high softening point glass powder in terms of ease of adjustment of the refractive index in the weight distribution curve is preferable. In consideration of dispersibility and filling properties in the paste and suppression of light scattering during exposure, a filler having an average particle size of 0.1 to 3.0 μm and a maximum particle size of 20 μm or less can be preferably used.

  When adding a low softening point glass and a filler as the inorganic component, the proportion of the low softening point glass powder in the inorganic component is preferably 50% by volume to 98% by volume. It is preferable for the content ratio to be 50% by volume or more because sintering during firing becomes easy and the porosity of the pattern after firing can be kept small. Further, if it is 98% by volume or less, it is possible to control the fluidity of the entire inorganic component at the time of firing, to prevent the deformation of the pattern shape, to improve the mechanical strength of the pattern after firing, and to lack due to impact. This is preferable because there is an advantage that a difficult pattern can be formed.

  The ratio of the low softening point glass powder and filler in the inorganic component can be calculated from the blending ratio of each component at the time of preparing the paste, but the paste dry film or dry film obtained by applying and drying the photosensitive paste It can also be determined by observing the cross section of the fired paste film obtained by firing with a scanning electron microscope. A cross section perpendicular to the film surface of the paste dry film or paste fired film may be observed with a scanning electron microscope, and the type of inorganic component may be distinguished based on the density of the image, and image analysis may be performed. The relationship between the contrast of the image and the inorganic component can be specified by elemental analysis using X-rays. As an evaluation area of the scanning electron microscope, for example, an area of about 20 μm × 100 μm is targeted, and observation may be performed at about 1000 to 3000 times.

The high softening point glass powder that can be preferably used has, for example, the following composition in oxide notation.
Lithium oxide, sodium oxide or potassium oxide 0-5% by mass
Silicon oxide 15-50% by mass
Boron oxide 5-25% by mass
Zinc oxide 0-20% by mass
Aluminum oxide 10-50% by mass
Magnesium oxide or calcium oxide 1-15% by mass
Barium oxide or strontium oxide 0-10% by mass
When the paste of the present invention is a photosensitive paste, the refractive index of the filler is preferably 1.45 to 1.65. By matching the refractive indexes of the inorganic component and the organic component and suppressing light scattering, highly accurate pattern processing becomes easy.

The inorganic component is preferably contained in the solid content of the paste at a total content of 35 to 80% by volume, more preferably 40 to 70% by volume. Here, solid content means the organic component except the inorganic component contained in a paste, and a solvent. If the content of the inorganic component is less than 35% by volume, the pattern shrinkage due to firing increases, and the shape tends to be unfavorable. Moreover, since it will become difficult to apply | coat uniformly when it exceeds 80 volume%, it is unpreferable.

  The content ratio (volume%) of the inorganic component in the solid content can be controlled by the addition amount (% by mass) in consideration of the density of the inorganic component and the organic component when preparing the paste. In addition, as a method of analyzing the content ratio of the inorganic component, there are a method of obtaining by thermogravimetry (TGA) and density measurement of the fired film of the inorganic component, or transmission electron of a paste dry film obtained by applying and drying the paste. There is a method of obtaining by image analysis of a microscope observation image. When calculating | requiring by the thermogravimetry and the density measurement of the baking film | membrane of an inorganic component, for example, about 10 mg of pastes is used as a sample, and the weight change from room temperature to 600 degreeC is evaluated by TGA (for example, "TGA-50" by Shimadzu Corporation). To do. Usually, since the solvent in the paste evaporates at 100 to 150 ° C., the ratio of the weight after heating up to 600 ° C. relative to the weight after the solvent evaporation (corresponding to the weight of the inorganic component because the organic component is removed) The mass ratio of the inorganic component and the organic component is obtained. On the other hand, the content ratio can be evaluated by evaluating the density of the inorganic component based on the film thickness, area and mass of the fired film. Moreover, when calculating | requiring a content rate by transmission electron microscope observation, the cross section perpendicular | vertical to the film surface of a paste dry film | membrane is observed with a transmission electron microscope (for example, "JEM-4000EX" by JEOL Ltd.), image The image analysis may be performed by distinguishing the inorganic component and the organic component according to the density of the image. As an evaluation area of the transmission electron microscope, for example, an area of about 20 μm × 100 μm is targeted, and observation may be performed at about 1000 to 3000 times.

  The paste in the present invention needs to contain an organic component. Here, the organic component only needs to have an appropriate viscosity when applying the paste, and maintain the pattern shape when the paste is applied and dried as necessary. The organic component used in the paste of the present invention is selected by the partition forming process and is not particularly limited. For example, a cellulose compound typified by ethyl cellulose, an acrylic polymer typified by polyisobutyl methacrylate, or the like can be used. Moreover, resins such as polyvinyl alcohol, polyvinyl butyral, methacrylic acid ester polymer, acrylic acid ester polymer, acrylic acid ester-methacrylic acid ester copolymer, α-methylstyrene polymer, and butyl methacrylate are listed.

  When the paste of the present invention is a photosensitive paste, it is characterized by containing a photosensitive organic component. The photosensitive organic component is selected from at least one of a photosensitive monomer, a photosensitive oligomer, and a photosensitive polymer. If necessary, non-photosensitive polymer components, antioxidants, organic dyes, photopolymerization initiators, sensitizers, sensitizers, plasticizers, thickeners, dispersants, organic solvents, precipitation inhibitors Organic components such as can be added as needed.

  The photosensitive paste as used in the present invention refers to a film that has been coated and dried, and is irradiated with actinic rays to cause the irradiated portion to undergo a reaction such as photocrosslinking, photopolymerization, photodepolymerization, and photomodification. A paste whose chemical structure changes to enable development with a developer. In particular, the present invention provides a negative photosensitive paste that can be patterned by making the irradiated part insoluble in the developer by irradiation with actinic light and then removing only the non-irradiated part with the developer. Good characteristics can be obtained. The actinic light here means light in the wavelength region of 250 to 1100 nm causing such a chemical reaction. Specifically, ultraviolet light such as an ultrahigh pressure mercury lamp and a metal halide lamp, visible light such as a halogen lamp, helium- Specific examples include laser beams having specific wavelengths such as a cadmium laser, a helium-neon laser, an argon ion laser, a semiconductor laser, a YAG laser, and a carbon dioxide gas laser.

  An alkali-soluble polymer can be preferably used as the photosensitive polymer. This is because the polymer is alkali-soluble, so that an aqueous alkaline solution can be used as a developer instead of an organic solvent having a problem with the environment. As the alkali-soluble polymer, an acrylic copolymer can be preferably used. The acrylic copolymer is a copolymer containing at least an acrylic monomer as a copolymerization component. Specific examples of the acrylic monomer include methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n -Butyl acrylate, sec-butyl acrylate, isobutyl acrylate, tert-butyl acrylate, n-pentyl acrylate, allyl acrylate, benzyl acrylate, butoxyethyl acrylate, butoxytriethylene glycol acrylate, cyclohexyl acrylate, dicyclopentanyl acrylate, di Cyclopentenyl acrylate, 2-ethylhexyl acrylate, glycerol acrylate, glycidyl acrylate, heptadecafluorodecyl acrylate 2-hydroxyethyl acrylate, isobornyl acrylate, 2-hydroxypropyl acrylate, isodexyl acrylate, isooctyl acrylate, lauryl acrylate, 2-methoxyethyl acrylate, methoxyethylene glycol acrylate, methoxydiethylene glycol acrylate, octafluoropentyl acrylate, phenoxy Acrylic monomers such as ethyl acrylate, stearyl acrylate, trifluoroethyl acrylate, acrylamide, aminoethyl acrylate, phenyl acrylate, 1-naphthyl acrylate, 2-naphthyl acrylate, thiophenol acrylate, benzyl mercaptan acrylate, and these acrylates into methacrylates Listed are alternatives It is. As the copolymer component other than the acrylic monomer, a compound having a carbon-carbon double bond can be used, but preferably styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, α-methylstyrene. Styrenes such as chloromethyl styrene and hydroxymethyl styrene, 1-vinyl-2-pyrrolidone and the like.

  In order to impart alkali solubility to the acrylic copolymer, it is achieved by adding an unsaturated acid such as an unsaturated carboxylic acid as a monomer. Specific examples of the unsaturated acid include acrylic acid, methacrylic acid, itaconic acid, crotonic acid, maleic acid, fumaric acid, vinyl acetate, or acid anhydrides thereof. The acid value of the polymer after adding these is preferably in the range of 50-150.

  When using an acrylic copolymer, in order to increase the reaction rate of the curing reaction by exposure of the photosensitive paste, an acrylic copolymer having a carbon-carbon double bond at the side chain or molecular end may be used. preferable. Examples of the group having a carbon-carbon double bond include a vinyl group, an allyl group, an acrylic group, and a methacryl group. In order to add such a functional group to an acrylic copolymer, a glycidyl group or an isocyanate group and a carbon-carbon double bond with respect to the mercapto group, amino group, hydroxyl group, or carboxyl group in the acrylic copolymer. And a method of making an addition reaction of a compound having acrylic acid chloride, methacrylic acid chloride or allyl chloride.

  Examples of the compound having a glycidyl group and a carbon-carbon double bond include glycidyl methacrylate, glycidyl acrylate, allyl glycidyl ether, glycidyl ethyl acrylate, crotonyl glycidyl ether, glycidyl crotonate, and glycidyl isocrotonate. Examples of the compound having an isocyanate group and a carbon-carbon double bond include acryloyl isocyanate, methacryloyl isocyanate, acryloylethyl isocyanate, and methacryloylethyl isocyanate.

  Furthermore, the photosensitive paste of the present invention may contain a non-photosensitive polymer component as an organic component, for example, a cellulose compound such as methylcellulose and ethylcellulose, a high molecular weight polyether, and the like.

  The photosensitive monomer is a compound containing a carbon-carbon unsaturated bond. Specific examples thereof include methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, sec-butyl acrylate. , Isobutyl acrylate, tert-butyl acrylate, n-pentyl acrylate, allyl acrylate, benzyl acrylate, butoxyethyl acrylate, butoxytriethylene glycol acrylate, cyclohexyl acrylate, dicyclopentanyl acrylate, dicyclopentenyl acrylate, 2-ethylhexyl acrylate, glycerol Acrylate, glycidyl acrylate, heptadecafluorodecyl acrylate, 2-hydroxyethyl acrylate , Isobornyl acrylate, 2-hydroxypropyl acrylate, isodexyl acrylate, isooctyl acrylate, lauryl acrylate, 2-methoxyethyl acrylate, methoxyethylene glycol acrylate, methoxydiethylene glycol acrylate, octafluoropentyl acrylate, phenoxyethyl acrylate, stearyl acrylate, Trifluoroethyl acrylate, allylated cyclohexyl diacrylate, 1,4-butanediol diacrylate, 1,3-butylene glycol diacrylate, ethylene glycol diacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, polyethylene glycol diacrylate, di Pentaerythritol hexaac Rate, dipentaerythritol monohydroxypentaacrylate, ditrimethylolpropane tetraacrylate, glycerol diacrylate, methoxylated cyclohexyl diacrylate, neopentyl glycol diacrylate, propylene glycol diacrylate, polypropylene glycol diacrylate, triglycerol diacrylate, trimethylolpropane Triacrylate, acrylamide, aminoethyl acrylate, phenyl acrylate, phenoxyethyl acrylate, benzyl acrylate, 1-naphthyl acrylate, 2-naphthyl acrylate, bisphenol A diacrylate, diacrylate of bisphenol A-ethylene oxide adduct, bisphenol A-propylene oxide Adjunct Diacrylate, thiophenol acrylate, benzyl mercaptan acrylate, a monomer in which 1 to 5 hydrogen atoms of these aromatic rings are substituted with chlorine or bromine atoms, or styrene, p-methylstyrene, o-methyl Styrene, m-methyl styrene, chlorinated styrene, brominated styrene, α-methyl styrene, chlorinated α-methyl styrene, brominated α-methyl styrene, chloromethyl styrene, hydroxymethyl styrene, carboxymethyl styrene, vinyl naphthalene, Examples include vinyl anthracene, vinyl carbazole, and those obtained by substituting some or all of the acrylates in the molecule with methacrylate, γ-methacryloxypropyltrimethoxysilane, 1-vinyl-2-pyrrolidone, and the like. In the polyfunctional monomer, the group having an unsaturated bond may be a mixture of an acryl group, a methacryl group, a vinyl group, and an allyl group. In the present invention, one or more of these can be used.

  The photosensitive paste used in the present invention preferably further contains a urethane compound. By including a urethane compound, the flexibility of the paste dry film is improved, the stress during firing can be reduced, and defects such as cracks and disconnections can be effectively suppressed. Moreover, by containing a urethane compound, thermal decomposability improves and an organic component becomes difficult to remain | survive in a baking process. Examples of the urethane compound preferably used in the present invention include compounds represented by the following general formula (1).

Here, R ¹ and R ² are selected from the group consisting of a substituent containing an ethylenically unsaturated group, hydrogen, an alkyl group having 1 to 20 carbon atoms, an aryl group, an aralkyl group, and a hydroxyaralkyl group. Yes, they may be the same or different. R3 is an alkylene oxide group or alkylene oxide oligomer, and R4 is an organic group containing a urethane bond. n is an integer of 1-10.

As such a urethane compound, a compound containing an ethylene oxide unit is preferable. More preferably, in the general formula (1), R ⁴ is an oligomer containing an ethylene oxide unit (hereinafter referred to as EO) and a propylene oxide unit (hereinafter referred to as PO), and the EO content in the oligomer Is a compound in the range of 8 to 70% by mass. Since EO content rate is 70 mass% or less, a softness | flexibility improves further and a baking stress can be made small, Therefore A defect can be suppressed effectively. Furthermore, the thermal decomposability is improved, and the organic components are less likely to remain in the subsequent firing step. Moreover, compatibility with another organic component improves because EO content rate is 8% or more.

  It is also preferred that the urethane compound has a carbon-carbon double bond. When the carbon-carbon double bond of the urethane compound reacts with the carbon-carbon double bond of another crosslinking agent and is contained in the crosslinked product, polymerization shrinkage can be further suppressed.

  Specific examples of urethane compounds preferably used in the present invention include UA-2235PE (molecular weight 18000, EO content 20%), UA-3238PE (molecular weight 19000, EO content 10%), UA-3348PE (molecular weight 22000, EO). Content rate 15%), UA-5348PE (molecular weight 39000, EO content rate 23%) (above, manufactured by Shin-Nakamura Chemical Co., Ltd.) and the like, but are not limited thereto. Moreover, you may use these compounds in mixture.

  It is preferable that the content rate of a urethane compound is 0.1-20 mass% of the organic component except a solvent. By setting the content to 0.1% by mass or more, the flexibility of the paste dry film can be improved, and the firing shrinkage stress when the paste dry film is fired can be reduced. When the content exceeds 20% by mass, the dispersibility of the organic component and the inorganic component is lowered, and the concentrations of the monomer and the photopolymerization initiator are relatively lowered, so that defects are likely to occur.

  As the photopolymerization initiator, a photoradical initiator that generates radicals upon irradiation with an active light source can be preferably used. Specific examples include benzophenone, methyl o-benzoylbenzoate, 4,4-bis (dimethylamine) benzophenone, 4,4-bis (diethylamino) benzophenone, 4,4-dichlorobenzophenone, 4-benzoyl-4- Methyl diphenyl ketone, dibenzyl ketone, fluorenone, 2,2-diethoxyacetophenone, 2,2-dimethoxy-2-phenyl-2-phenylacetophenone, 2-hydroxy-2-methylpropiophenone, pt-butyldichloro Acetophenone, thioxanthone, 2-methylthioxanthone, 2-chlorothioxanthone, 2-isopropylthioxanthone, diethylthioxanthone, benzyl, benzyldimethylketanol, benzylmethoxyethyl acetal, benzoin, benzoin methyl Ether, benzoin butyl ether, anthraquinone, 2-t-butylanthraquinone, 2-amylanthraquinone, β-chloroanthraquinone, anthrone, benzanthrone, dibenzosuberone, methyleneanthrone, 4-azidobenzalacetophenone, 2,6-bis (p -Azidobenzylidene) cyclohexanone, 2,6-bis (p-azidobenzylidene) -4-methylcyclohexanone, 2-phenyl-1,2-butadion-2- (o-methoxycarbonyl) oxime, 1-phenyl-propanedione- 2- (o-ethoxycarbonyl) oxime, 1,3-diphenyl-propanetrione-2- (o-ethoxycarbonyl) oxime, 1-phenyl-3-ethoxy-propanetrione-2- (o-benzoyl) oxime, Mihira -Ketone, 2-methyl- [4- (methylthio) phenyl] -2-morpholino-1-propanone, naphthalenesulfonyl chloride, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -1-butanone, quinoline Sulfonyl chloride, N-phenylthioacridone, 4,4-azobisisobutyronitrile, diphenyl disulfide, benzthiazole disulfide, triphenylformine, camphorquinone, carbon tetrabrominated, tribromophenyl sulfone, benzoin peroxide and A combination of a photoreducing dye such as eosin or methylene blue and a reducing agent such as ascorbic acid or triethanolamine can be used. In the present invention, one or more of these can be used. A photoinitiator is added in 0.05-20 mass% with respect to the total amount of a photosensitive monomer and a photosensitive polymer, More preferably, it adds in 0.1-18 mass%. If the amount of the polymerization initiator is too small, the photosensitivity may be deteriorated. If the amount of the photopolymerization initiator is too large, the residual ratio of the exposed portion may be too small.

  Moreover, a sensitizer can be used with a photoinitiator, a sensitivity can be improved or the wavelength range effective for reaction can be expanded. Specific examples of the sensitizer include 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2-isopropylthioxanthone, 2,3-bis (4-diethylaminobenzal) cyclopentanone, 2,6-bis ( 4-dimethylaminobenzal) -4-methylcyclohexanone, mihira-ketone, 4,4-bis (diethylamino) chalcone, p-dimethylaminocinnamylideneindanone, p-dimethylaminobenzylideneindanone, 2- (p- Dimethylaminophenylvinylene) isonaphthothiazole, 1,3-bis (4-dimethylaminobenzal) acetone, 1,3-carbonylbis (4-diethylaminobenzal) acetone, 3,3-carbonylbis- (7-diethylamino) Coumarin), triethanolamine, methyldiethanol Amine, triisopropanolamine, N-phenyl-N-ethylethanolamine, N-phenylethanolamine, N-tolyldiethanolamine, methyl 4-dimethylaminobenzoate, ethyl 4-dimethylaminobenzoate, isoamyl dimethylaminobenzoate , Isoamyl diethylaminobenzoate, ethyl (2-dimethylamino) benzoate, 4-dimethylaminobenzoate (n-butoxy) ethyl, 2-dimethylhexyl 4-dimethylaminobenzoate, 3-phenyl-5-benzoylthio Examples include tetrazole and 1-phenyl-5-ethoxycarbonylthiotetrazole. In the present invention, one or more of these can be used. Some sensitizers can also be used as photopolymerization initiators. When adding a sensitizer to the photosensitive paste of this invention, the addition amount becomes like this. Preferably it is 0.05-10 mass% with respect to the organic component except a solvent, More preferably, it is 0.1-10 mass%. By setting the addition amount of the sensitizer within this range, good photosensitivity can be obtained while maintaining the remaining ratio of the exposed portion.

  In the present invention, it is also preferable to use an antioxidant. The antioxidant has a radical chain inhibiting action, a triplet elimination action, and a hydroperoxide decomposition action. When an antioxidant is added to the photosensitive paste, the antioxidant captures radicals and returns the energy state of the excited photopolymerization initiator and sensitizer to the ground state, thereby causing excess light due to scattered light. Since the reaction is suppressed and a photoreaction occurs abruptly at an exposure amount that cannot be suppressed by the antioxidant, it is possible to increase the contrast of dissolution and insolubility in the developer. Specifically, p-benzoquinone, naphthoquinone, p-xyloquinone, p-toluquinone, 2,6-dichloroquinone, 2,5-diacetoxy-p-benzoquinone, 2,5-dicaproxy-p-benzoquinone, hydroquinone, p-t -Butylcatechol, 2,5-dibutylhydroquinone, mono-t-butylhydroquinone, 2,5-di-t-amylhydroquinone, di-t-butyl-p-cresol, hydroquinone monomethyl ether, α-naphthol, hydrazine hydrochloride , Trimethylbenzylammonium chloride, trimethylbenzylammonium oxalate, phenyl-β-naphthylamine, parabenzylaminophenol, di-β-naphthylparaphenylenediamine, dinitrobenzene, trinitrobenzene, picric acid, quinonedioxime, Lohexanone oxime, pyrogallol, tannic acid, triethylamine hydrochloride, dimethylaniline hydrochloride, cuperone, 2,2′-thiobis (4-tert-octylphenolate) -2-ethylhexylaminonickel- (II), 4, 4′-thiobis- (3-methyl-6-tert-butylphenol), 2,2′-methylenebis- (4-methyl-6-tert-butylphenol), triethylene glycol-bis [3- (t-butyl-5 -Methyl-4-hydroxyphenyl) propionate], 1,6-hexanediol-bis [(3,5-di-t-butyl-4-hydroxyphenyl) propionate], 1,2,3-trihydroxybenzene, etc. Although it is mentioned, it is not limited to these. In the present invention, one or more of these can be used. The addition amount of the antioxidant is preferably 0.01 to 30% by mass, more preferably 0.05 to 20% by mass in the photosensitive paste. By making the addition amount of the antioxidant within this range, it is possible to maintain the photosensitivity of the photosensitive paste, and maintain the degree of polymerization and maintain the pattern shape, while increasing the contrast between the exposed portion and the non-exposed portion. it can.

  It is also preferable to use an ultraviolet absorber for the photosensitive paste of the present invention. By adding an ultraviolet absorber, scattered light inside the paste due to exposure light can be absorbed and scattered light can be weakened. The ultraviolet absorber is particularly effective as long as it has excellent absorbance at wavelengths near the g-line, h-line, and i-line. Specific examples include benzophenone compounds, cyanoacrylate compounds, salicylic acid compounds, and benzotriazole compounds. Examples thereof include compounds, indole compounds, and inorganic fine-particle metal oxides. Among these, benzophenone compounds, cyanoacrylate compounds, benzotriazole compounds, and indole compounds are particularly effective. Specific examples thereof include 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2,2′-dihydroxy-4,4′-dimethoxybenzophenone, 2,2′-dihydroxy-4,4′-. Dimethoxy-5-sulfobenzophenone, 2-hydroxy-4-methoxy-2′carboxybenzophenone, 2-hydroxy-4-methoxy-5-sulfobenzophenone trihydrate, 2-hydroxy-4-n-octoxybenzophenone, 2- Hydroxy-4-octadecyloxybenzophenone, 2,2 ′, 4,4′-tetrahydroxybenzophenone, 4-dodecyloxy-2-hydroxybenzophenone, 2-hydroxy-4- (2-hydroxy-3-methacryloxy) propoxybenzophenone, 2- (2'-G Roxy-3 ′, 5′-di-t-butylphenyl) benzotriazole, 2- (2′-hydroxy-3′-t-butyl-5′-methylphenyl) -5-chlorobenzotriazole, 2- (2 '-Hydroxy-3', 5'-di-t-butylphenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy-4'-n-octoxyphenyl) benzotriazole, 2-ethylhexyl- 2-cyano-3,3-diphenyl acrylate, 2-ethyl-2-cyano-3,3-diphenyl acrylate, indole UV absorbers BONASORB UA-3901, BONASORB UA-3902, BONASORB UA-3911, SOM -2-0008 (above, manufactured by Orient Chemical Co., Ltd.), Basic Blue, Sudanbu Chromatography, Sudan R, Sudan I, Sudan II, Sudan III, Sudan IV, Oil Orange SS, Oil Violet, Oil Yellow OB (manufactured by Aldrich Inc.) but are not limited to such. Furthermore, a methacryl group or the like may be introduced into the skeleton of these ultraviolet absorbers and used as a reaction type. In the present invention, one or more of these can be used.

  In the present invention, a photo-fading compound can also be used as the ultraviolet absorber. A photochromic compound absorbs light in the wavelength region of actinic rays when irradiated with light in the wavelength region of actinic rays and passes through changes in the chemical structure such as photodegradation and photodenaturation, and then the wavelength region of the active light source The absorbance at is lower than that before irradiation. Usually, in the photosensitive paste method, since exposure is performed using g-line (436 nm), h-line (405 nm), and i-line (365 nm) of an ultrahigh pressure mercury lamp, the photo-fading compound used in the present invention is also g. Absorption is preferably in the line, h-line, and i-line regions. By adding the photo-fading compound to the photosensitive paste, it is possible to prevent exposure light from entering the non-exposed part, which is a part not exposed to exposure light in pattern design, and to suppress the pattern bottom thickness. . Further, in the exposed portion, the photochromic compound absorbs the energy of the exposure light and does not gradually absorb through photodecomposition or photomodification, so that sufficient exposure light easily reaches the lower layer. Therefore, the photocuring contrast between the non-exposed portion and the exposed portion becomes clear, and the exposure amount margin can be reliably improved. Specific examples include photodegradable dyes, photoacid generators, photobase generators, photodegradable compounds such as nitrone compounds, and photomodifying compounds such as azo dyes and photochromic compounds. Specific examples of the photoacid generator include onium salts, halogen-containing compounds, diazomethane compounds, sulfone compounds, sulfonic acid ester compounds, sulfonimide compounds, diazoketone compounds, and the like.

  As for the content rate of a ultraviolet absorber, 0.001-1 mass% is preferable in a photosensitive paste, More preferably, it is 0.001-0.5 mass%. By making the addition amount of the ultraviolet absorber within this range, it is possible to absorb the scattered light, suppress the pattern bottom thickness, and maintain the sensitivity to the exposure light.

  In the present invention, it is also preferable to use an organic dye as a mark for exposure and development. By adding a dye and coloring it, the visibility is improved, and it becomes easy to distinguish the portion where the paste remains during development and the portion where it has been removed. Although it does not specifically limit as organic dye, The thing which does not remain in the insulating film after baking is preferable. Specifically, anthraquinone dyes, indigoid dyes, phthalocyanine dyes, carbonium dyes, quinoneimine dyes, methine dyes, quinoline dyes, nitro dyes, nitroso dyes, benzoquinone dyes, naphthoquinone dyes, phthalimide dyes Dyes and perinone dyes can be used. In particular, it is preferable to select one that absorbs light having a wavelength in the vicinity of h-line and i-line, for example, a carbonium dye such as basic blue. The addition amount of the organic dye is preferably 0.001 to 1% by mass with respect to the organic components excluding the solvent.

  It is also preferable to use an organic solvent in order to adjust the viscosity when applying the paste to the substrate according to the application method. As the organic solvent used at this time, methyl cellosolve, ethyl cellosolve, butyl cellosolve, butyl carbitol, ethyl carbitol, butyl carbitol acetate, ethyl carbitol acetate, methyl ethyl ketone, dioxane, acetone, cyclohexanone, cyclopentanone, isobutyl alcohol, Isopropyl alcohol, tetrahydrofuran, dimethyl sulfoxide, γ-butyrolactone, bromobenzene, chlorobenzene, dibromobenzene, dichlorobenzene, bromobenzoic acid, chlorobenzoic acid, and the like, and organic solvent mixtures containing one or more of these are used.

  The paste of the present invention is prepared by mixing each component of the inorganic component and each component of the organic component so as to have a predetermined composition, and then performing main kneading using a kneading device such as a three roller. Further, it is also preferable to appropriately filter and degas the paste after the main kneading.

  The flat display panel manufacturing method of the present invention is characterized in that the above-mentioned paste is applied on a substrate and baked to form an insulating pattern. This makes it possible to form an insulating pattern with little residual organic components after firing and no coloration, so that a flat display panel having excellent display characteristics such as luminance and color purity and high reliability can be obtained. it can.

  In addition, the flat display panel manufacturing method of the present invention is characterized in that the above-mentioned photosensitive paste is applied on a substrate, exposed, developed, and baked to form an insulating pattern. As a result, it is possible not only to form a non-colored insulating pattern with a small amount of residual organic components after firing, but also to form a high-definition insulating pattern with high accuracy, such as brightness and color purity. The flat display panel having excellent display characteristics and high reliability can be obtained stably and at low cost.

The flat display panel of the present invention is a flat display panel having a partition mainly composed of a low softening point glass having a softening point of 570 to 620 ° C., and the low softening point glass includes silicon oxide, boron oxide and alkali metal. It contains an oxide, the silicon oxide content in the low softening point glass is X (SiO ₂ ) (mol%), and the boron oxide content in the low softening point glass is X (B ₂ O ₃ ) (mol%). ), When the alkali metal oxide content in the low softening point glass is X (M ₂ O) (mol%), the value of A represented by the following formula (1) is within the range of 35 to 46. It is characterized by being.

A = X (SiO ₂ ) + X (B ₂ O ₃ ) −X (M ₂ O) (1)
By setting the value of A within the range of 35 to 46, a flat display panel having excellent display characteristics such as luminance and color purity and high reliability can be obtained. The value of A is preferably in the range of 36 to 45, more preferably in the range of 38 to 44. The main component here means a component having the largest volume fraction among all solid components. The content ratio of the low softening point glass can be obtained by observing the cross section of the partition wall with an electron microscope and analyzing the cross sectional area of the low softening point glass in the total cross sectional area of the solid component. The low softening point glass and other solid components can be distinguished by the difference in light and shade of the image. Moreover, components can be strictly distinguished by mapping atoms by a technique such as a scanning analysis microscope (SEM-EDX) equipped with an energy dispersive X-ray spectrometer.

  The constituent components and the content of the low softening point glass, which is the main component of the partition walls, can be quantitatively determined by Auger electron spectroscopic analysis. Specifically, the low softening point glass is distinguished by the difference in density of the SEM image of the partition wall cross section, and elemental analysis is performed by Auger electron spectroscopy. In addition, other known analysis means such as selectively cutting out the low softening point glass from the partition wall and performing atomic absorption analysis or inductively coupled plasma (ICP) emission spectroscopic analysis can be used supplementarily.

  The softening point of the low softening point glass, which is the main component of the partition wall, can be measured using a differential thermal analyzer (DTA) after selectively cutting the low softening point glass from the partition wall. From the DTA curve obtained by measuring the glass powder, the endothermic end temperature at the endothermic peak can be extrapolated by the tangent method.

  In the flat display panel of the present invention, the low softening point glass powder as the main component of the partition wall contains zinc oxide, and the content thereof is in the range of 1.5 to 5.5 mol%. . Zinc oxide is characterized by containing 1.5 mol% or more because it has the effect of lowering the softening point without greatly changing the thermal expansion coefficient of the glass. Further, when the content is increased, the stability of the glass is lowered, the refractive index is increased, the reactivity with the organic component in the paste is increased, and the paste viscosity is likely to increase with time, so that 5.5 mol. It is the characteristic to mix | blend in the range below%. Preferably it is 2.5-3.3 mol%.

  In the flat display panel of the present invention, the low softening point glass powder as the main component of the partition contains an alkali metal oxide, an alkaline earth metal oxide and zinc oxide, and the total content thereof is 24 to 30 mol%. It is in the range of. Alkali metal oxides, alkaline earth metal oxides, and zinc oxide are all effective in lowering the softening point, and are therefore characterized by a total content of 24 mol% or more. When the content rate increases, the refractive index increases. Since it becomes high, it is the characteristic that the total is mix | blended in 30 mol% or less. Preferably it is 25-29 mol%, More preferably, it is 26-28 mol%.

  Hereinafter, as a procedure for producing a flat display panel, a procedure for producing a plasma display member and a plasma display panel using a photosensitive paste method will be described, but the invention is not necessarily limited thereto. Here, the basic structure of the plasma display will be described by taking the most common alternating current (AC) type plasma display as an example.

  The plasma display panel is a member formed by sealing the front plate and the rear plate so that the phosphor layer formed on the front plate and / or the rear plate faces the inner space. The discharge gas is sealed inside. That is, on the front plate, a transparent electrode (sustain electrode, scan electrode) for display discharge is formed on the substrate on the display surface side. A bus electrode may be formed on the back side of the transparent electrode for the purpose of forming a lower resistance electrode. However, the bus electrode is made of Ag, Cr / Cu / Cr or the like and is often opaque. Therefore, unlike the transparent electrode, it interferes with the display of the cell, and is preferably provided at the outer edge of the display surface. In the case of an AC type plasma display, a transparent dielectric layer and an MgO thin film as a protective film are often formed on the upper layer of the electrode. On the back plate, electrodes (address electrodes) for selecting cells to be displayed are formed. The partition walls and phosphor layers for partitioning the cells may be formed on either or both of the front plate and the back plate, but are often formed only on the back plate. In the plasma display panel, the front plate and the back plate are sealed, and an internal space between the two is filled with a discharge gas such as Xe-Ne or Xe-Ne-He.

  First, regarding the panel manufacturing process, a method for producing a front plate will be described. As the substrate, “PP8” (manufactured by Nippon Electric Glass Co., Ltd.) or “PD200” (manufactured by Asahi Glass Co., Ltd.), which is a heat resistant glass for soda glass or plasma display panel, can be used. The size of the glass substrate is not particularly limited, and a glass substrate having a thickness of 1 to 5 mm can be used.

  First, indium-tin oxide (ITO) is sputtered on a glass substrate, and a pattern is formed by a photoetching method. Subsequently, the black electrode paste for black electrodes is printed. The black electrode paste is composed mainly of an organic binder, a black pigment, conductive powder, and a photosensitive component when used in a photolithography method. As the black pigment, a metal oxide is preferably used. Examples of metal oxides include titanium black, copper, iron, manganese oxides and their composite oxides, and cobalt oxides. Cobalt oxides are less susceptible to fading when mixed with glass and fired. Is excellent. Examples of the conductive powder include metal powder and metal oxide powder. As the metal powder, gold, silver, copper, nickel or the like that is usually used as an electrode material can be used without any particular limitation. Since this black electrode has a high resistivity, an electrode paste having a high conductivity (for example, a material containing silver as a main component) is printed on the black electrode paste in order to produce a bus electrode by producing an electrode with a low resistivity. Print on the side. As this conductive paste, an electrode paste used for an address electrode can also be suitably used. Then, batch exposure / development is performed to produce a bus electrode pattern. In order to ensure the conductivity, a highly conductive electrode paste may be printed again before development, and may be collectively developed after re-exposure. After the bus electrode pattern is formed, baking is performed. Thereafter, it is preferable to form a black stripe or a black matrix in order to improve contrast. The film thicknesses of the black electrode paste after firing and the conductive paste after firing are each preferably in the range of 1 to 5 μm. Moreover, it is preferable that the line | wire width after baking is 20-100 micrometers.

  Next, a transparent dielectric layer is formed using a transparent dielectric paste. The transparent dielectric paste is mainly composed of an organic binder, an organic solvent, and glass, but an additive such as a plasticizer may be appropriately added. The method for forming the transparent dielectric layer is not particularly limited. For example, the transparent dielectric paste is applied to the entire surface of the electrode forming substrate by screen printing, bar coater, roll coater, die coater, blade coater, spin coater, or the like. After application, the thick film can be formed by drying using an optional oven such as a ventilating oven, a hot plate, an infrared drying oven, or vacuum drying. It is also possible to make the transparent dielectric paste into a green sheet and laminate it on the electrode forming substrate. The thickness is preferably 0.01 to 0.03 mm.

  Next, firing is performed in a firing furnace. The firing atmosphere and temperature vary depending on the type of paste and substrate, but firing is performed in air, in an atmosphere of nitrogen, hydrogen, or the like. As the firing furnace, a batch-type firing furnace or a roller conveyance type continuous firing furnace can be used. The baking temperature is preferably a temperature at which the resin to be used sufficiently debinds. Usually, when an acrylic resin is used, baking is performed at 430 to 650 ° C. If the firing temperature is too low, the resin component tends to remain, and if it is too high, the glass substrate may be distorted and cracked.

Further, a protective film is formed. As the protective film, MgO, MgGd ₂ O ₄ , BaGd ₂ O ₄ , Sr _0.6 Ca _0.4 Gd ₂ O ₄ , Ba _0.6 Sr _0.4 Gd ₂ O ₄ , SiO ₂ , TiO ₂ , Al ₂ O ₃ and at least one kind from the above-mentioned group of low softening point glasses are preferably used, and MgO is particularly preferable. A known technique such as electron beam evaporation or ion plating can be used as a method for forming the protective film.

  Next, a method for manufacturing the back plate will be described. As the glass substrate, soda glass, “PD200”, “PP8” or the like can be used as in the case of the front plate. An address stripe electrode pattern is formed on a glass substrate with a metal such as silver, aluminum, chromium, or nickel. As a forming method, these metal powders and a metal paste mainly composed of an organic binder are pattern-printed by screen printing, or after applying a photosensitive metal paste using a photosensitive organic component as an organic binder, It is possible to use a photosensitive paste method in which pattern exposure is performed using a mask, unnecessary portions are dissolved and removed in a development step, and further heated and baked at 350 to 600 ° C. to form an electrode pattern. Further, an etching method can be used in which after chromium or aluminum is vapor-deposited on a glass substrate, a resist is applied, and after the resist is subjected to pattern exposure and development, unnecessary portions are removed by etching. Furthermore, it is preferable to provide a dielectric layer on the address electrode. By providing the dielectric layer, it is possible to improve the stability of discharge and to prevent the partition wall formed on the upper layer of the dielectric layer from falling or peeling off. As a method of forming the dielectric layer, there is a method in which a dielectric paste mainly composed of an inorganic component such as glass powder or high softening point glass powder and an organic binder is printed or applied on the whole surface by screen printing, a slit die coater, or the like. is there.

  Next, a method for forming partition walls by a photosensitive paste method will be described. The partition pattern is not particularly limited, but a lattice shape, a waffle shape, or the like is preferable. First, the photosensitive paste of this invention is apply | coated on the board | substrate in which the dielectric material was formed. As a coating method, methods such as a bar coater, a roll coater, a slit die coater, a blade coater, and screen printing can be used. The coating thickness can be determined in consideration of the desired partition wall height and the shrinkage rate due to baking of the paste. The coating thickness can be adjusted by the number of coatings, screen mesh, paste viscosity, and the like. In this invention, it is preferable to apply | coat so that the application thickness after drying may be 100 micrometers or more. By setting it to 100 μm or more, a sufficient discharge space can be obtained, and the luminance of the plasma display panel can be improved by expanding the coating range of the phosphor.

  The applied partition paste is dried and then exposed. In general, the exposure is performed through a photomask, as in normal photolithography. Alternatively, a method of directly drawing with a laser beam or the like without using a photomask may be used. As the exposure apparatus, a stepper exposure machine, a proximity exposure machine, or the like can be used. Examples of the active light source used at this time include near ultraviolet rays, ultraviolet rays, electron beams, X-rays, and laser beams. Among these, ultraviolet rays are most preferable, and as the light source, for example, a low-pressure mercury lamp, a high-pressure mercury lamp, an ultrahigh-pressure mercury lamp, a halogen lamp, or a germicidal lamp can be used. Among these, an ultrahigh pressure mercury lamp is suitable. Although exposure conditions vary depending on the coating thickness, exposure is usually performed for 0.01 to 30 minutes using an ultrahigh pressure mercury lamp having an output of 1 to 100 mW / cm 2.

  After the exposure, development is performed by utilizing the difference in solubility between the exposed portion and the non-exposed portion in the developer. Usually, the immersion method, the spray method, the brush method, and the like are performed. As the developer, an organic solvent in which an organic component in the photosensitive paste can be dissolved can be used. However, when a compound having an acidic group such as a carboxyl group is present in the photosensitive paste, development can be performed with an alkaline aqueous solution. As the alkaline aqueous solution, sodium hydroxide, sodium carbonate, potassium hydroxide aqueous solution or the like can be used. However, it is preferable to use an organic alkaline aqueous solution because an alkaline component can be easily removed during firing.

  As the organic alkali, a general amine compound can be used. Specific examples include tetramethylammonium hydroxide, trimethylbenzylammonium hydroxide, monoethanolamine, and diethanolamine.

  The density | concentration of aqueous alkali solution is 0.05-5 mass% normally, More preferably, it is 0.1-1 mass%. If the alkali concentration is too low, it is difficult to remove the soluble part, and if the alkali concentration is too high, the pattern may be peeled off or corroded, which is not preferable. The development temperature during development is preferably 20 to 50 ° C. in terms of process control.

  Moreover, the partition may be composed of two or more layers. By using a structure of two or more layers, the configuration range of the partition wall shape can be expanded three-dimensionally. For example, in the case of a two-layer structure, the first layer is applied and exposed in a stripe shape, then the second layer is applied, the first layer is exposed to a stripe shape in the vertical direction, and development is performed, thereby causing unevenness. It is possible to form a partition wall having a cross-beam structure. Next, baking is performed by holding at a temperature of 520 to 620 ° C. for 10 to 60 minutes in a baking furnace to form partition walls.

  The photosensitive paste of the present invention is suitable for the formation of the above-described barrier ribs, and the photosensitive paste of the present invention can form barrier ribs with a small amount of residual organic components, and has excellent display characteristics such as luminance and color purity. A reliable flat display can be manufactured.

Next, a phosphor is formed using the phosphor paste. It can be formed by a photolithography method using a phosphor paste, a dispenser method, a screen printing method, or the like. Although the thickness of a fluorescent substance is not specifically limited, It is 10-30 micrometers, More preferably, it is 15-25 micrometers. The phosphor powder is not particularly limited, but the following phosphors are preferable from the viewpoint of light emission intensity, chromaticity, color balance, lifetime, and the like. Blue is an aluminate phosphor (for example, BaMgAl ₁₀ O ₁₇ : Eu) or CaMgSi ₂ O ₆ activated with divalent europium. In the case of green, Zn ₂ SiO ₄ : Mn, YBO ₃ : Tb, BaMg ₂ Al ₁₄ O ₂₄ : Eu, Mn, BaAl ₁₂ O ₁₉ : Mn, and BaMgAl ₁₄ O23: Mn are preferable in terms of panel luminance. More preferably _Zn 2 _SiO 4: is Mn. In red, (Y, Gd) BO ₃ : Eu, Y ₂ O ₃ : Eu, YPVO: Eu, and YVO ₄ : Eu are also preferable. More preferred is (Y, Gd) BO ₃ : Eu. When the phosphor is formed through the firing step, it may be performed simultaneously with the above-described firing of the dielectric layer and the partition wall.

  Next, a method for manufacturing a plasma display panel will be described. After sealing the back plate and the front plate, after evacuating while heating the space formed between the two substrates, a discharge gas composed of He, Ne, Xe, etc. is sealed and sealed . From both sides of discharge voltage and brightness. Xe-Ne mixed gas having 5 to 15% by volume of Xe is preferable. In order to increase the generation efficiency of ultraviolet rays, Xe may be further increased to about 30% by volume.

  Finally, a plasma display panel can be manufactured by mounting and aging the drive circuit.

Hereinafter, the present invention will be specifically described by way of examples. However, the present invention is not limited to this.
(Examples 1-16, Comparative Examples 1-10)
A. Evaluation of Particle Size Distribution of Glass Powder Using a particle size distribution measuring device (“MT3300” manufactured by Nikkiso Co., Ltd.), the average particle size d ₅₀ and the maximum particle size d _max of the glass powder were evaluated. Glass powder was put into a sample chamber filled with water, and measurement was performed after ultrasonic treatment for 300 seconds.
B. Evaluation of softening point of glass powder DTA obtained by heating from room temperature to 20 ° C / min using alumina powder as a standard sample using a differential thermal analyzer (“Differential Differential Thermal Balance TG8120” manufactured by Rigaku Corporation) From the curve, the endothermic end temperature at the endothermic peak was extrapolated by the tangent method to obtain the softening point Ts.
C. Preparation of paste A paste was prepared according to the following procedure.
a. The organic solid content composed of the raw materials below the organic component is weighed and mixed at a weight ratio shown in Table 1, and 42 parts by weight of an organic solvent (γ-butyrolactam) is added to 40.1 parts by weight of the organic solid, followed by mixing and stirring. Thus, an organic vehicle was produced.
Composition of organic solids:
Photosensitive monomer M-1 (trimethylolpropane triacrylate): 6 parts by weight Photosensitive monomer M-2 (tetrapropylene glycol dimethacrylate): 6 parts by weight Photopolymer (methacrylic acid / methyl methacrylate / styrene = 40/40) / 30 addition of 0.4 equivalent of glycidyl methacrylate to the carboxyl group of the copolymer, weight average molecular weight 43000, acid value 100): 18 parts by weight photopolymerization initiator (2-benzyl-2 -Dimethylamino-1- (4-morpholinophenyl) -1-butanone, IC369 (trade name) manufactured by BASF): 5 parts by weight sensitizer (2,4-diethylthioxanthone): 1 part by weight antioxidant (1 , 6-hexanediol-bis [(3,5-di-tert-butyl-4-hydroxyphenyl) propionate]) : 4 parts by weight UV absorber (Sudan IV (manufactured by Tokyo Ohka Kogyo Co., Ltd., absorption wavelength: 350 nm and 520 nm)): 0.1 parts by weight

b. 80% by volume of a low softening point glass powder having a composition below the inorganic component and 20% by volume of a high softening point glass powder were mixed and used as an inorganic component.
Low softening point glass powder: Glass powder having the composition, softening point, and particle size distribution shown in Tables 2 and 3 (Note that the symbols in the table have the following meanings: SiO ₂ : silicon oxide, B ₂ O ₃ : boron oxide. , ZnO: zinc oxide, _Li 2 O: lithium oxide, _Na 2 O: sodium _{oxide, K} 2 O: potassium oxide, MgO: magnesium oxide, CaO: calcium oxide, BaO: barium oxide, _Al 2 _{O 3:} aluminum oxide)
High softening point glass powder (sodium oxide: 1% by mass, silicon oxide: 40% by mass, boron oxide: 10% by mass, aluminum oxide: 33% by mass, zinc oxide: 4% by mass, calcium oxide: 9% by mass, titanium oxide : 3% by mass, softening point Ts: 740 ° C., d ₅₀ : 2 μm, d _max : 10 μm)
c. Preparation of Paste The organic vehicle and inorganic powder obtained as described above are mixed so that the organic solid content in the total solid content excluding the organic solvent is 42% by volume, and the inorganic component content is 58% by volume. After adjustment and addition, the mixture was kneaded with a three-roller kneader to obtain a photosensitive paste.
D. Evaluation of residual organic component amount 0.75 g of a mixture of 20 g of the glass powder shown in Tables 2 and 3 and 40 g of an ethylcellulose solution (ethylcellulose: 25 mass%, γ-BL: 75 mass%) was placed in a 250 mL aluminum container, and aluminum Covered with lid, sealed and baked. The firing conditions were 10 ° C./min to 500 ° C. in air and 15 minutes at 500 ° C. 15 mg of the powder after firing was measured using a pyrolysis gas chromatograph mass spectrometer (GCMS-QP2010Plus, manufactured by Shimadzu Corporation) at 550 ° C. in a He atmosphere, and the residual organic component was determined as the total value of all peak areas derived from the organic component. evaluated. When the total value of the peak areas was 5 × 10 ⁶ or more, many residual organic components were considered inappropriate.
E. Production of Evaluation Substrate An evaluation substrate was produced by the following procedure. Address electrode patterns were formed on a “PD-200” glass substrate (42 inches) manufactured by Asahi Glass Co., Ltd. by photolithography using a photosensitive silver paste. Next, a dielectric layer having a thickness of 20 μm was formed on the glass substrate on which the address electrodes were formed by screen printing. Thereafter, the photosensitive paste was uniformly applied on the back plate glass substrate on which the address electrode pattern and the dielectric layer were formed by screen printing until a desired thickness was obtained. In order to avoid the occurrence of pinholes and the like in the coating film, coating and drying were repeated several times or more so that the thickness after drying was 150 μm. Intermediate drying was performed at 100 ° C. for 10 minutes. Next, exposure was performed through an exposure mask. The exposure mask is a chromium mask designed so that a vertical pitch of 150 μm, a vertical line width of 25 μm, a horizontal pitch of 450 μm, a horizontal line width of 25 μm, and a grid-like insulating pattern can be formed in a plasma display. Exposure was carried out eight points exposure at 25 mJ / cm ² intervals in the range of 250~375mJ / cm ² by varying the exposure time by using a ultra-high pressure mercury lamp with an output of 50 mW / cm ^2. Thereafter, a 0.3% by mass aqueous solution of monoethanolamine was developed by showering for 150 seconds and washed with water to remove the uncured space. Furthermore, the partition was formed by hold | maintaining and baking at 590 degreeC for 30 minutes, and the board | substrate for evaluation was obtained.
F. Yellowing Evaluation Of the substrate prepared in E, a part having a partition wall bottom width of 55 μm was measured with a spectrocolorimeter (“CM-2002” manufactured by Konica Minolta) SCE mode, and a b ^* value was evaluated. When the b ^* value is 10 or more, yellowing of the partition walls is extremely inappropriate.
G. Viscosity stability Using a B-type viscometer with digital arithmetic function (Brookfield, USA, DV-II), the viscosity of the paste prepared in C at a temperature of 25 ° C. and a rotation speed of 3 rpm was measured. The viscosity of the paste was measured twice after the first day of production and after storage for 7 days at 23 ° C., and the rate of increase in viscosity after 7 days of storage was calculated based on the viscosity of the first day of production to evaluate the viscosity stability. When the viscosity increase rate after 7 days is 10% or more, the viscosity stability is poor and is not suitable.
H. The partition wall of the substrate manufactured with the minimum bottom partition wall width E was observed, the partition bottom width where peeling did not occur was measured, and the minimum value was defined as the minimum partition wall bottom width. Since the partition top width is about 38 μm under the production conditions of E, the smaller the minimum partition bottom width is in the range of 38 μm or more, the more preferable the rectangular partition is formed. When the minimum partition wall bottom width is 50 μm or more, a thin partition pattern cannot be formed, which is inappropriate.
I. Surface Roughness Evaluation The paste prepared in C was applied on a glass substrate (PD-200, 5 inches manufactured by Asahi Glass Co., Ltd.) with a film thickness of 50 μm using a blade coater, and then dried at 100 ° C. for 30 minutes. Then, it hold | maintained at 590 degreeC for 30 minutes and baked, and the sample for surface roughness evaluation was produced. For the surface roughness, arithmetic average roughness (Ra) measured by Surfcom (Tokyo Seimitsu "1400D") was measured. The measurement conditions were ISO-'97 standard “surface roughness measurement”, measurement length: 1 mm, measurement speed: 0.30 mm / s. A paste having a surface roughness Ra of 2.0 μm or more is not suitable because the display characteristics of a panel manufactured using this paste deteriorate.

  Tables 2 and 3 show the evaluation results of the pastes obtained in Examples 1 to 16 and Comparative Examples 1 to 10.

  In Examples 1 to 16, A is in the range of 35 to 46, B is in the range of 1.5 to 5.5, and C is in the range of 24 to 30, In some cases, the remaining organic components were small and good.

In Comparative Example 1 in which A is smaller than 35, the content of alkali metal oxide in the glass is large, the b ^* value is increased, and the partition walls are yellowed, which is not possible.

  In Comparative Examples 2 to 4 where A is larger than 46, the silicon oxide and boron oxide contents in the glass are large, and the acid-base balance of the glass is poor.

  In Comparative Example 5 where B is less than 1.5, the surface roughness Ra was large and impossible because of the small amount of zinc oxide.

  In Comparative Example 6 where B is greater than 5.5, the amount of increase in the viscosity of the paste was not possible due to the large amount of zinc oxide.

  In Comparative Example 7 where C is less than 24, the total amount of zinc oxide, alkali metal oxide, and alkaline earth metal oxide is small, so that the surface roughness Ra is not large.

  In Comparative Examples 8 to 10 where C is greater than 30, since the total amount of zinc oxide, alkali metal oxide, and alkaline earth metal oxide is large, the refractive index difference of the low softening point glass powder is high and the organic component is different. Became larger. As a result, the bottom width of the minimum partition wall was increased, and it was impossible to form a thin pattern.

  INDUSTRIAL APPLICABILITY The present invention can be usefully used as a paste for forming a partition wall having a small residual organic component. Further, a partition wall having a small amount of remaining organic components is formed, and it can be effectively used as a flat panel display with excellent display characteristics such as luminance and color purity and high panel reliability.

A = X (SiO ₂ ) + X (B ₂ O ₃ ) −X (M ₂ O) (1)
B = X (ZnO) (2)
C = X (M ₂ O) + X (MO) + X (ZnO) (3)
(2) The paste as described in (1) above, wherein the organic component contains a photosensitive organic component.
(3) A method for producing a flat display panel, wherein the paste according to any one of (1) to (2) above is applied onto a substrate and baked to form an insulating pattern.
(4) A method for producing a flat display panel, comprising applying a paste according to (2) above on a substrate, exposing, developing, and baking to form an insulating pattern.
(5) A panel for a flat display having a partition wall consisting mainly of low softening point glass having a softening point of five hundred and seventy to six hundred twenty ° C., the low softening point glass is silicon oxide, boron oxide, alkali metal oxides, alkaline earth metalloid oxide and contains zinc oxide, the silicon oxide content of the low-softening point in glass X (SiO 2) _(mol%), boron oxide content of the low-softening point in glass X (B _{2 O} 3) _(mol%), wherein the alkali metal oxide content of the low-softening point in glass X (M 2 _O) (mol%), containing an alkaline earth metal oxides of said low softening point in the glass the rate X (MO) (mol%), wherein when the zinc oxide content of the low-softening point in glass was X (ZnO) (mol%), the value of a as represented by the following formula (1) 35 -B and the value of B represented by the following formula (2) is 1. 5.5 in the range of, and, the panel for a flat display wherein the value of C of the following formula (3) is in the range of 24-30.

Claims (5)

Containing a low softening point glass powder having a softening point of 570 to 620 ° C. and an organic component, the low softening point glass powder containing silicon oxide, boron oxide, alkali metal oxide, alkaline earth metal oxide and zinc oxide; The silicon oxide content in the low softening point glass powder is X (SiO ₂ ) (mol%), the boron oxide content in the low softening point glass powder is X (B ₂ O ₃ ) (mol%), the low The alkali metal oxide content in the softening point glass powder is X (M ₂ O) (mol%), the alkaline earth metal oxide content in the low softening point glass powder is X (MO) (mol%), When the zinc oxide content in the low softening point glass powder is X (ZnO) (mol%), the value of A represented by the following formula (1) is in the range of 35 to 46, and The value of B represented by the formula (2) is in the range of 1.5 to 5.5. Inner and and and paste the values of C represented by the following formula (3) is being in the range of 24-30.
A = X (SiO ₂ ) + X (B ₂ O ₃ ) −X (M ₂ O) (1)
B = X (ZnO) (2)
C = X (M ₂ O) + X (MO) + X (ZnO) (3) The paste according to claim 1, wherein the organic component includes a photosensitive organic component. A method for producing a flat display panel, comprising applying a paste according to claim 1 on a substrate and firing to form an insulating pattern. A method for producing a flat display panel, comprising applying a paste according to claim 2 on a substrate, exposing, developing, and baking to form an insulating pattern. A flat display panel having a partition mainly composed of a low softening point glass having a softening point of 570 to 620 ° C., wherein the low softening point glass powder is silicon oxide, boron oxide, alkali metal oxide, alkaline earth metal oxidation And the zinc oxide content in the low softening point glass powder is X (SiO ₂ ) (mol%), and the boron oxide content in the low softening point glass powder is X (B ₂ O ₃ ) (Mol%), the alkali metal oxide content in the low softening point glass powder is X (M ₂ O) (mol%), the alkaline earth metal oxide content in the low softening point glass powder is X (MO) (mol%), when the zinc oxide content in the low softening point glass powder is X (ZnO) (mol%), the value of A represented by the following formula (1) is 35 to 46 Within the range and represented by the following formula (2) A flat display panel, wherein the value of B is in the range of 1.5 to 5.5, and the value of C represented by the following formula (3) is in the range of 24 to 30: .
A = X (SiO ₂ ) + X (B ₂ O ₃ ) −X (M ₂ O) (1)
B = X (ZnO) (2)
C = X (M ₂ O) + X (MO) + X (ZnO) (3)