KR20060052074A - Front plate and rear plate for plasma display panel, and composition for use therein - Google Patents

Abstract

assignment

The present invention provides a front plate or a back plate of a PDP in which copper is present on either the substrate or the electrode on the surface of the dielectric layer side, wherein the front plate for the PDP using a dielectric layer obtained without sufficient bubbles in the dielectric layer after firing and having sufficient flatness. And a back plate.

Resolution

The dielectric layer after baking has a thickness of 5 to 15 µm, and the dielectric layer before firing has (a) an inorganic powder and (b) a hydroxyl group in the side chain, and the amount of hydroxyl groups contained in the side chain is contained in the side chain per monomer structural unit. By converting the average number of hydroxyl groups into 0.4 or more binder resins per monomer unit, bubbles are not left in the dielectric layer after firing and sufficient flatness can be obtained.

Plasma Display, Front Panel, Back Panel

Description

Front panel and back panel for plasma display panel, composition used for it {FRONT PLATE AND REAR PLATE FOR PLASMA DISPLAY PANEL, AND COMPOSITION FOR USE THEREIN}

1 is an exploded view of a plasma display having a waffle structured cell;

※ Explanation of symbols for main parts of drawing

1: front panel 10: glass substrate

11: electrode 110: transparent electrode

112: bus electrode 12: dielectric layer

12A: unbaked dielectric layer 16: spacer layer

19: shield 2: back plate

20: substrate 21: address electrode

22: dielectric layer 24: rib

26: phosphor layer

[Patent Document 1] Japanese Unexamined Patent Publication No. 2002-328470

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a front plate and a back plate used in a plasma display panel (hereinafter referred to as PDP) as a self-luminous flat panel display using gas discharge, and a composition used therein.

Plasma displays that form images by self-emitting a large number of fine cells using discharge phenomena have excellent features that could not be realized in conventional displays such as large screens, thin films, light weights, and flats. .

In general, a PDP is a structure in which a pair of electrodes arranged regularly on two opposing glass substrates is formed, and a rare gas mainly containing Ne, Xe, and He is enclosed therebetween. A voltage is applied between these electrodes, and discharge is generated in a small cell around the electrode to display each cell by emitting light. The PDP displays information by selectively discharging the regularly arranged cells. This PDP has a direct current type (DC type) and an alternating current type (AC type), and both are further classified into a refresh driving method and a memory driving method due to differences in display functions and driving methods.

Fig. 1 shows an exploded perspective view of the main portion of a plasma display having a waffle structure cell as a structural example of an AC PDP. In addition to the cell structure, there are a straight structure and the like. In the plasma display, the front plate 1 in which the composite electrode 11 made of the transparent electrode 110 and the bus electrode 112 are formed in parallel with each other, and the address electrode 21 are mutually orthogonal to each other are perpendicular to the composite electrode 11. It is a display element in which the back plate 2 formed in parallel is mutually arrange | positioned, and is integrated. The said front plate 1 has the transparent glass substrate 10 used as a display surface, and the said composite electrode 11 is arrange | positioned inside this glass substrate 10, ie, the back plate 2 side. The dielectric layer 12 is formed to cover the composite electrode 11, and a patterned spacer layer 16 is formed on the dielectric layer 12, and the surface of the dielectric layer 12 and the spacer layer 16 is formed. The protective film 19 which consists of MgO etc. is formed in this. On the other hand, the address electrode 21 is disposed on the front plate 1 side of the substrate 20 of the back plate 2, and the dielectric layer 22 is formed to cover the address electrode 21. The following light emitting portion is formed on (22).

The light emitting portion positioned in the space where the composite electrode 11 and the address electrode 21 intersect is composed of a plurality of cells. The plurality of cells are constituted by ribs 24 formed in the longitudinal and transverse directions on the dielectric layer 22, covering the wall surface of the ribs 24 and the surface of the dielectric layer 22 in the ribs, that is, the inner surface and the bottom surface of each cell. The phosphor layer 26 is formed. In the plasma display, the electric field is formed by applying a predetermined voltage from an alternating current power source between the composite electrodes of the front panel, thereby causing discharge within the cell, and causing the phosphor layer 26 to emit light by ultraviolet rays generated by the discharge. .

As a dielectric layer of such a front plate and a back plate, the method of using the composition for dielectric layer formation containing the glass powder and acrylic resin which has a hydroxyl group like patent document 1 is known. However, when copper is present in either the substrate or the electrode on the surface of the dielectric layer side, bubbles may form on the copper surface, and bubbles may remain in the dielectric layer even after firing, so that sufficient flatness cannot be obtained and a good dielectric layer can be obtained. There was a problem that could not.

In terms of cost, conductivity, and ease of use, copper may be used for either the substrate or the electrode on the surface of the dielectric layer side of the PDP. In this case, however, bubbles are generated on the copper surface during firing, bubbles remain in the dielectric layer even after firing, and sufficient flatness cannot be obtained and a good dielectric layer cannot be obtained.

Moreover, when using resin which has a hydroxyl group as a resin component, when the ratio of the hydroxyl group of a side chain is large, there existed a problem that the thermal contraction at the time of baking becomes large, and the dielectric layer which is favorable to enter a crack at the time of shrinkage cannot be obtained. In particular, in the case of the dielectric layer used for the front plate and the back plate of the PDP, there is a fear that the PDP itself becomes a defective product due to cracks due to heat shrinkage during firing.

Means to solve the problem

In view of these phenomena, the inventors have intensively studied, and as a result, the thickness of the dielectric layer after firing is set to 5 to 15 µm, and the amount of hydroxyl groups contained in the inorganic powder and the side chain of the dielectric layer before firing is determined per monomer structural unit. A front plate of a PDP in which copper is present on any one of the substrate or the electrode on the surface of the dielectric layer side, in which the dielectric layer contains 0.4 or more binder resins per monomer unit in terms of the average number of hydroxyl groups contained in the side chain of the monomer. Alternatively, in the dielectric layer used for the back plate, it has been found that the front plate and the back plate for the PDP using the dielectric layer obtained without sufficient bubbles in the dielectric layer after firing and having sufficient flatness can be produced. It was completed.

That is, the present invention is directed to a PDP using a dielectric layer in which a front surface or a back plate of a PDP in which copper is present on either the substrate or the electrode on the surface of the dielectric layer side does not leave bubbles in the dielectric layer after firing and has sufficient flatness. It is an object to provide a front plate and a back plate.

In addition, an object of the present invention is to provide a composition for forming a dielectric layer for forming the dielectric layer of the front plate and the back plate.

To practice the invention  Best form for

EMBODIMENT OF THE INVENTION Below, embodiment of this invention is described in detail in the following order.

[A] Dielectric Layer Formation Composition

[B] Method for producing composition for forming dielectric layer

[C] Sheet Unbaked Body for PDP Dielectric Layer Formation

[D] Manufacturing method of front plate for PDP and manufacturing method of back plate for PDP

[A] Dielectric Layer Formation Composition

The composition for dielectric layer formation of this invention contains at least an inorganic powder and binder resin which has a hydroxyl group in a side chain.

The composition for dielectric layer formation of this invention dissolves or disperse | distributes the binder resin which has a hydroxyl group in a side chain in a composition, and disperse | distributes an inorganic powder into a paste form.

In the composition for forming a dielectric layer of the present invention, as the binder resin, a hydroxyl group-containing resin containing a hydroxyl group at the side chain end is used from the viewpoint of controlling the softening point of the dielectric layer and dispersibility of the inorganic powder.

By making the softening point of the composition lower than the firing temperature, it is possible to obtain a good dielectric in which sufficient flatness is maintained without bubbles remaining in the dielectric layer after firing. When the softening point of the composition is higher than the firing temperature, bubbles may not remain in the conductor, and a conductor in which sufficient flatness is maintained may not be obtained. Moreover, when there are many hydroxyl groups in binder resin, the dispersibility of an inorganic powder increases, the particle | grains of an inorganic powder become small and uniform, and the quality of the dielectric material after baking improves, such as the improvement of flatness and the precipitation of the metal contacting in the lower layer. do.

(a) inorganic powder

The inorganic powder used in the present invention, and that the glass frit vitrified by firing preferably, for example, PbO-SiO _{2 based, PbO-B 2 O 3 -SiO} 2 type, ZnO-SiO ₂ type, ZnO-B ₂ O ₃ -SiO ₂ -based, BiO-SiO ₂ -based, BiO-B ₂ O ₃ -SiO ₂ -based, PbO-B ₂ O ₃ -SiO ₂ -Al ₂ O ₃ -based, PbO-ZnO-B ₂ O _3- SiO ₂ system etc. can be mentioned.

Moreover, you may use inorganic powders, such as ceramics (cordy light etc.) and a metal. Specific examples of such inorganic powders include cobalt oxide, iron oxide, chromium oxide, nickel oxide, copper oxide, manganese oxide, neodium oxide, vanadium oxide, cerium oxide yellow, cadmium oxide, ruthenium oxide, silica, magnesia, and spinel. Each oxide, such as Na, K, Mg, Ca, Ba, Ti, Zr, Al, etc. are mentioned.

As for the particle diameter of an inorganic powder, an average particle diameter is 0.1-10 micrometers, More preferably, 0.5-8 micrometers is used. An average particle diameter of 10 mu m or less is preferable because flatness of the dielectric surface after firing is obtained, and an average particle diameter of 0.1 mu m or more is preferable because fine voids are not formed during firing and insulation failure does not occur. Examples of the shape of the inorganic powder include spherical, block, flake, and dendrite, and can be used alone or in combination of two or more thereof.

In addition, the inorganic powder may be a mixture of fine particles having different physical properties. In particular, by using ceramic powders having different glass frits and hot softening points, etc., the shrinkage at the time of firing can be suppressed. It is preferable to mix | blend this inorganic powder with the shape, combination of a physical property value, etc. according to the use of the composition for dielectric layer formation.

It is preferable to mix | blend an inorganic powder in the ratio of 100-1000 mass parts with respect to 100 mass parts of all the organic components (including organic solvent, binder resin, etc.).

(b) Binder resin which has a hydroxyl group in a side chain

In the composition of this invention, resin which has a hydroxyl group in a side chain is used as binder resin.

As such a binder resin, what superposed | polymerized or copolymerized the monomer which can introduce | transduce hydroxyl groups like the following can be used.

As a monomer which can introduce | transduce such a hydroxyl group, (meth) acrylic acid ester, ethylenically unsaturated carboxylic acid, and other copolymerizable monomers can be used preferably, For example, benzyl acrylate, benzyl methacrylate, cyclohexyl acrylate, cyclo Hexyl methacrylate, phenoxyethyl acrylate, phenoxyethyl methacrylate, phenoxy polyethylene glycol acrylate, phenoxy polyethylene glycol methacrylate, styrene, nonylphenoxy polyethylene glycol monoacrylate, nonylphenoxy polyethylene glycol mono Methacrylate, nonylphenoxypolypropylene monoacrylate, nonylphenoxypolypropylene monomethacrylate, 2-hydroxy-3-phenoxypropylacrylate, 2-acryloyloxyethyl phthalate, 2-acryloyl Oxyethyl-2-hydroxyethyl phthalate, 2-methacryloyl jade Ethyl-2-hydroxypropyl phthalate, methyl acrylate, ethyl acrylate, methyl methacrylate, ethyl methacrylate, n-propyl acrylate, n-propyl methacrylate, i-propyl acrylate, i-propyl meth Acrylate, n-butyl acrylate, n-butyl methacrylate, i-butyl acrylate, i-butyl methacrylate, sec-butyl acrylate, sec-butyl methacrylate, tert-butyl acrylate, tert- Butyl methacrylate, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, 3-hydroxypropyl acrylate, 3-hydroxy Hydroxypropyl methacrylate, 2-hydroxybutyl acrylate, 2-hydroxybutyl methacrylate, 3-hydroxybutyl acrylate, 3-hydroxybutyl methacrylate, 4-hydroxybutyl acrylate , 4-hydroxybutyl methacrylate, 3-ethylhexyl arcacrylate, ethylene glycol monoacrylate, ethylene glycol monomethacrylate, glycerol acrylate, glycerol methacrylate, dipentaerythritol monoacrylate, dipenta Erythritol monomethacrylate, dimethylaminoethyl acrylate, dimethylaminoethyl methacrylate, tetrahydrofurfuryl acrylate, tetrahydrofurfuryl methacrylate, acrylic acid, methacrylic acid, crotonic acid, cinnamic acid, maleic anhydride Maleic acid, fumaric acid, itaconic acid, itaconic anhydride, citraconic acid, citraconic anhydride, and the like. Among these, acrylic acid and methacrylic acid are used preferably.

Moreover, as another copolymerizable monomer, for example, the fumaric acid ester which replaced the exemplary compound of the (meth) acrylic acid ester mentioned above with fumarate, the maleic acid ester which changed with maleate, and the crotonic acid ester which changed with crotonate , Itaconic acid esters converted to itaconate, α-methylstyrene, o-vinyltoluene, m-vinyltoluene, p-vinyltoluene, o-chlorostyrene, m-chlorostyrene, p-chlorostyrene, o-methoxy Styrene, m-methoxystyrene, p-methoxystyrene, vinyl acetate, vinyl butyrate, vinyl propionate, acrylamide, methacrylamide, acrylonitrile, methacrylonitrile, isoprene, chloroprene, 3-butadiene, and the like. have.

The amount of hydroxyl groups in the side chain of the binder resin used in the present invention is preferably 0.4 or more per monomer structural unit in terms of the average number of hydroxyl groups contained in the side chain per monomer structural unit of the binder resin. When the hydroxyl group content in the molecule is 0.4 or more per one structural unit, a good dielectric layer having good dispersibility of the inorganic powder, control of the dielectric softening point, and sufficient flatness can be obtained.

The amount of hydroxyl groups in the side chain of the binder resin is 0.4 or more per monomer structural unit in terms of the average number of hydroxyl groups contained in the side chain per monomer structural unit of the binder resin, so that the inorganic powder is hydrogen-bonded with the binder resin. It is easy and the dispersibility of the inorganic powder is increased. As a result, the particles of the inorganic powder become small and uniform, and the quality of the dielectric layer is improved. By improving the quality of the layer, for example, precipitation of the metal in the lower layer can be controlled. Moreover, the generation | occurrence | production of the linear unevenness | corrugation (linear generation) and the crater of the composition layer which generate | occur | produce by making a large part of particle into a lump state can be suppressed.

(c) other ingredients

The composition for dielectric layer formation of this invention contains the above-mentioned (a) inorganic powder and (b) binder resin which has a hydroxyl group in a side chain as an essential component, and can contain another component further according to the use. .

In order to adjust a characteristic, you may combine binder resin which has a hydroxyl group in a side chain, and another binder resin. Examples of other binder resins include cellulose derivatives such as cellulose, hydroxymethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, carboxymethyl cellulose, carboxyethyl cellulose and carboxyethyl methyl cellulose, and these cellulose derivatives and ethylenically unsaturated resins. Copolymer with a carboxylic acid, a (meth) acrylate compound, etc. can be used. As the binder resin, polyvinyl alcohols such as polybutyral resin, which is a reaction product of polyvinyl alcohol and butyl aldehyde, δ-valerolactone, ε-caprolactone, β-propiolactone, α-methyl-β -Propiolactone, β-methyl-β-propiolactone, α-methyl-β-propiolactone, β-methyl-β-propiolactone, α, α-dimethyl-β-propiolactone, β, polyesters obtained by ring-opening polymerization of lactones such as β-dimethyl-β-propiolactone, alkylene glycols such as ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, dipropylene glycol and neopentyl glycol alone or two Polyethers, such as polyesters obtained by condensation reaction with dicarboxylic acids, such as diol, maleic acid, a fumaric acid, glutaric acid, and adipic acid, more than a species, polyethyleneglycol, polypropylene glycol, polytetramethylene glycol, polypentamethylene glycol , Bisphenol A And polycarbonates which are reaction products with diols such as hydroquinone and dihydroxycyclohexane, and carbonyl compounds such as diphenyl carbonate, phosgene, and succinic anhydride. The above binder resins can be used alone or as a mixture of two or more kinds.

In this case, the ratio of the binder resin which has a hydroxyl group in a side chain is 30 mass parts or more, and the ratio of the other binder resin is 70 mass parts or less with respect to a total of 100 mass parts of binder resin which has a hydroxyl group in a side chain. Preferably, the ratio of the binder resin which has a hydroxyl group in a side chain is 50 mass parts or more, and the ratio of the other binder resin is 50 mass parts or less, More preferably, the ratio of the binder resin which has a hydroxyl group in a side chain is 70 mass parts or more, The ratio of another binder resin is 30 mass parts or less. When the ratio of another binder resin increases, since the dispersibility of an inorganic powder may fall, it is unpreferable.

It will not specifically limit, if it is an organic solvent which can melt | dissolve binder resin easily as an organic solvent used for this invention. As such an organic solvent, it is preferable to use at least one organic solvent selected from the group consisting of ethers, ketones, esters and alcohols.

As a specific example of the organic solvent which can be used for this invention, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether acetate, ethylene glycol diacetate, ethylene glycol diethyl ether, ethylene glycol dibutyl ether, Ethylene Glycol Dimethyl Ether, Ethylene Glycol Monophenyl Ether Acetate, Ethylene Glycol Monohexyl Ether Acetate, Glycerin Triacetate, Glycerin Trilaurylate, Diethylene Glycol Monomethyl Ether Acetate, Diethylene Glycol Monoethyl Ether Acetate, Diethylene Glycol Monobutyl Ether acetate, diethylene glycol diacetate, diethylene glycol dimethyl ether acetate, diethylene glycol diethyl ether acetate, diethylene glycol dibutyl ether acetate, diethylene glycol dibenzoate , Triethylene glycol dimethyl ether, triethylene glycol monomethyl ether acetate, propylene glycol diacetate, propylene glycol dimethyl ether, propylene glycol diethyl ether, propylene glycol dibutyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate , Propylene glycol monobutyl ether acetate, dipropylene glycol diacetate, dipropylene glycol dimethyl ether, dipropylene glycol diethyl ether, dipropylene glycol dibutyl ether, dipropylene glycol monomethyl ether acetate, dipropylene glycol monoethyl ether acetate, Dipropylene glycol monobutyl ether acetate, acetone, methyl ethyl ketone, methyl isobutyl ketone, acetylacetone, acetophenone, isophorone, ethyl-N-butyl ketone, diacetone alcohol (4-hydroxy-4-methyl-2- Penta ), Diisobutyl ketone, diisopropyl ketone, diethyl ketone, cyclohexanone, di-N-propyl ketone, methyl-N-amyl ketone (amyl methyl ketone), methylcyclohexanone, methyl-N-butyl ketone , Methyl-N-propyl ketone, methyl-N-hexyl ketone, methyl-N-heptyl ketone, diethyl adipic acid, trimethyl acetyl citrate, triethyl acetyl citrate, tributyl acetyl citrate, methyl acetate, acet acetate, ethyl acetate Butyl acetate, isoamyl benzoate, methyl benzoate, ethyl benzoate, butyl benzoate, propyl benzoate, benzyl benzoate, isoamyl formate, isobutyl formate, ethyl formate, butyl formate, propyl formate, hexyl formate, benzyl formate, methyl formate, Triethyl citrate, tributyl citrate, amyl acetate, allyl acetate, isoamyl acetate, methyl isoamyl acetate, methoxybutyl acetate, isobutyl acetate, isopropyl acetate, acetic acid Ethyl, methyl acetate, second hexyl acetate, 2-ethylhexyl acetate, 2-ethylbutyl acetate, cyclohexyl acetate, methylcyclohexyl acetate, n-butyl acetate, 2 butyl acetate, isopropyl acetate, benzyl acetate Methylcyclohexyl acetate, diamyl oxalate, dimethyl oxalate, diethyl oxalate, dibutyl oxalate, diethyl tartarate, dibutyl tartarate, amyl stearate, methyl stearate, ethyl stearate, butyl stearate, amyl lactate, methyl lactate Ethyl lactate, butyl lactate, phthalate ester, γ-butyrolactone, isoamyl propionate, methyl propionate, ethyl propionate, butyl propionate, benzyl propionate, diisopropyl maronate, dimethyl mate, diethyl maronate, dibutyl maronate, Isoamyl butyrate, isopropyl butyrate, methyl butyrate, ethyl butyrate, butyl butyrate, alkanes, toluene, hexane, Alcohols such as chlorhexane, cyclohexene, cyclopentane, halogenated hydrocarbons, nitrogen-containing compounds, methanol, ethanol, ethylene glycol, diethylene glycol, propylene glycol, 3-methoxy-3-methylbutanol, ethylene glycol monomethyl ether And alkyl ethers of polyhydric alcohols such as ethylene glycol monoethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, propylene glycol monomethyl ether, and propylene glycol monoethyl ether.

Moreover, the organic solvent of boiling point 250 degreeC or less, especially the organic solvent of boiling point 100 degreeC-200 degreeC are preferable. The above solvents may be used alone or in combination of two or more thereof. When several solvents are combined, it is preferable that the azeotropic temperature is 250 degrees C or less, and it is especially preferable that it is 100 to 200 degreeC, since manufacture becomes easy. It is preferable to mix | blend a solvent in the ratio of 30-500 mass parts, Preferably 50-300 mass parts, More preferably, 100-250 mass parts with respect to 100 mass parts of binder resin which has a hydroxyl group in (b) side chain. Do.

For the control of physical properties, monomers can be added within a range that does not impair the original properties. As a monomer, although the monomer illustrated by the binder resin which has a hydroxyl group in the above-mentioned (b) side chain is mentioned, The monomer which has two or more polymerizable ethylenically unsaturated bonds (henceforth a polyfunctional monomer) is preferable. As the polyfunctional monomer, for example, diacrylate or dimethacrylate of alkylene glycol such as ethylene glycol and propylene glycol, diacrylate or dimethacryl of polyalkylene glycol such as polyethylene glycol and polypropylene glycol And polyacrylates or polymethacrylates of polyhydric alcohols such as lates, glycerin, trimethylolpropane, pentaerythritol, dipentaerythritol, and modified dicarboxylic acids thereof. Among these, specifically, ethylene glycol diacrylate, ethylene glycol dimethacrylate, triethylene glycol diacrylate, triethylene glycol dimethacrylate, tetraethylene glycol diacrylate, tetraethylene glycol dimethacrylate, Propylene glycol diacrylate, propylene glycol dimethacrylate, polypropylene glycol diacrylate, polypropylene glycol dimethacrylate, trimethylol propane triacrylate, trimethylol propane trimethacrylate, tetramethylol propane tetraacrylate , Tetramethylol propane tetramethacrylate, pentaerythritol triacrylate, pentaerythritol trimethacrylate, pentaerythritol tetraacrylate, pentaerythritol tetramethacrylate, dipentaerythritol pentamethacrylate, di Pentaeri Tritol hexaacrylate, dipentaerythritol hexamethacrylate, etc. are mentioned.

Moreover, in order to provide plasticity, you may add a plasticizer. As a plasticizer, a well-known thing can be used and it is preferable that a boiling point is 200 degreeC or more and excellent in transparency of a liquid at room temperature. Examples of the plasticizer include dimethyl phthalate, diethyl phthalate, dibutyl phthalate, diheptyl phthalate, diheptane phthalate, di-2-ethylhexyl phthalate, diisobutyl phthalate, diisononyl phthalate, diisodecyl phthalate, dibutoxyethyl phthalate, and diphthalate. Phthalic acid compounds such as butyl benzyl, dioctyl phthalate and butyl phthalyl butyl glycolate, dimethyl adipic acid and diethyl adipic acid, dibutyl adipic acid and diheptane didipentane, di-2-ethylhexyl adipic acid and adipic acid Adipic acid compounds such as isobutyl, diisononyl adipicate, diisodecyl adipicate, dibutoxyethyl adipic acid, dibutyl benzyl adipic acid, dioctyl adipic acid, dimethyl sebacate or diethyl sebacinate, and seba Dibutyl succinate or diheptyl sebacate, di-2-ethylhexyl sebacinate or diisobutyl sebacinate, diisononyl sebacinate, diisodecyl sebacinate or dibutoxyethyl sebacinate, Sebacic acid compounds such as dibutyl benzyl sebacin and dioctyl sebacate, dimethyl azelate or diethyl azelate, dibutyl azelate, diheptyl azelate, di-2-ethylhexyl azelate or diisobutyl azelate Azelaic acid compounds such as diisononyl azelate, diisodecyl azelate, dibutoxyethyl azelate, dibutylbenzyl azelate, dioctyl azelate, triethyl phosphate, triphenyl phosphate, and tricredyl phosphate; Phosphoric acid compounds, such as trixylenyl phosphate and credil phosphate, fatty acid compounds, such as dioctyl sebacate and methyl acetyl ricinolate, epoxy compounds, such as diisodecyl-4,5-epoxytetrahydrophthalate, and tri Trimellitic acid compounds such as tributyl methacrylate and tri-2-ethylhexyl trimellitic acid, trimellitic acid trin-octyl and trimellitic acid triisodecyl, In addition, butyl oleate, chlorinated paraffin, polybutene, polyisobutylene, etc. are mentioned. These can mix | blend 1 type, or 2 or more types as needed.

Moreover, it is preferable to mix | blend a plasticizer with respect to 100 mass parts of binder resins which have a hydroxyl group in (b) side chain, 200 mass parts or less, Preferably it is 5-100 mass parts, More preferably, it is mix | blended in the ratio of 10-80 mass parts. Do.

[B] Method for producing composition for forming dielectric layer

The method for producing a composition for forming a dielectric layer of the present invention comprises a composition for forming a dielectric layer comprising a kneading step of mixing an inorganic powder, a binder resin having a hydroxyl group in a side chain, and other components as necessary and kneading the mixture. It is a manufacturing method.

In this invention, the mixing order of binder resin and an inorganic powder is not specifically limited. For example, binder resin and inorganic powder may be mixed at once, and binder resin may be previously dissolved in an organic solvent to adjust a binder component, and inorganic powder may be added and mixed to this binder component. Hereinafter, although the latter method is taken as an example, the manufacturing method of the composition for dielectric layer formation of this invention is demonstrated in detail, but the mixing order of each component is not limited to this.

First, the binder resin is dissolved and the binder component is adjusted by mixing the organic solvent and the binder resin with a stirrer. At this time, you may add various additives, such as a monomer, a plasticizer, a dispersing agent, a tackifier, a surface tension regulator, a stabilizer, and a foam remover.

After adjusting the binder component, the inorganic powder is added to the binder component to adjust the mixture, and the mixture is kneaded to disperse the inorganic powder. In a normal storage state, the inorganic powder adsorbs moisture in the atmosphere and has a hydroxyl group condensed with water on its surface. Therefore, in order to introduce a hydroxyl group into the surface, it is not necessary to perform special treatment on the inorganic powder itself, but in the case where it has been stored for a long time under drying, it is preferable to absorb the inorganic powder before use and add it to the binder component as necessary. Do.

Thus, the mixture which disperse | distributed the inorganic powder through the kneading process can be used as it is as a composition for dielectric layer formation of this invention.

[C] Sheet Unbaked Body for PDP Dielectric Layer Formation

The sheet-like unbaked body which concerns on this invention forms the composition film for dielectric layer formation by apply | coating the composition for dielectric layer formation of this invention on a release support film, and drying this coating film. For example, this sheet-like unbaked body can be used as a material for forming the dielectric layers of the plasma display front plate and the back plate. The sheet-like unbaked body of this invention is protected by the release film which can peel easily the surface of the composition film for dielectric layer formation, and becomes easy to store, convey, and handle.

Since the sheet-like unbaked body which concerns on this invention is formed using the composition for dielectric layer formation of this invention in which inorganic powder was disperse | distributed uniformly, it has high film flatness. In addition, since the occurrence of shrinkage at the time of firing can be suppressed, a dielectric layer having a uniform film thickness without cracks or the like can be obtained. Therefore, it becomes possible to manufacture a display panel of high quality.

In addition, although the sheet-like unbaked body of the present invention has an expiration date, the sheet-like unbaked body can be prepared in advance and stored for a predetermined period of time, so that the sheet-like unbaked body can be used immediately when manufacturing a display panel, thereby increasing the efficiency of manufacturing the display panel.

It is preferable to supply the sheet-like unbaked body of this invention in the form protected by the release film which can peel easily both surfaces of the composition film for dielectric layer formation. Specifically, a dielectric layer is formed on a temporary peelable support film, and a protective film is coated as a protective layer thereon.

As a support film used for manufacture of the sheet-like unbaked body of this invention, if the release film which can peel each layer formed on the support film easily from a support film and can transfer each layer on a glass substrate is specifically limited A plastic film made of a synthetic resin film such as polyethylene terephthalate, polyethylene, polypropylene, polycarbonate or polyvinyl chloride having a film thickness of 15 to 125 µm can be used, for example. It is preferable to release-process to the said support film so that transfer may become easy as needed.

In forming the composition film for forming a dielectric layer on a support film, the composition for forming a dielectric layer of the present invention is adjusted, and a dielectric layer is formed on the support film by using an applicator, a bar coater, a wire bar coater, a roll coater, a curtain flow coater, and the like. The composition for application is apply | coated. In particular, a roll coater is preferable because it is excellent in uniformity of film thickness and can form a thick film efficiently.

After the coating film is dried, a protective film is preferably applied to the surface of the composition film for forming a dielectric layer in order to stably protect the composition film for forming a dielectric layer when not in use. As this protective film, the polyethylene terephthalate film, polypropylene film, polyethylene film, etc. which are about 15-125 micrometers in thickness which coated or ignited silicone are preferable.

[D] Manufacturing method of front plate for PDP and manufacturing method of back plate for PDP

In manufacture of a display panel, the composition film for dielectric layer formation is made by peeling a protective film from the sheet-like unbaked body of this invention, combining the composition film for dielectric layer formation exposed to the electrode mounting surface of a glass substrate, and moving a heating roller on a support film. Thermocompression bonding to the surface of the substrate.

Thermocompression bonding is preferably carried out by heating the surface temperature of the substrate to 80 to 140 ° C. in a range of a roll pressure of 1 to 5 kg / cm ² and a moving speed of 0.1 to 10.0 m / min. The said glass substrate may be preheated, and the range of 40-100 degreeC is selected as a preheating temperature, for example.

The protective film peeled from the composition film for dielectric layer formation can be reused if it is wound up and preserve | saved in roll form with a winding roller sequentially.

In this way, after heat-bonding the composition film for dielectric layer formation to the surface of a board | substrate, a support film is peeled from the composition film for dielectric layer formation, and the composition film for dielectric layer formation is exposed to a surface. The support film peeled from the composition film for dielectric layer formation can also be reused if it is wound up by winding in a roll form with a winding roller and preserve | saved.

Thus, after forming the composition film for dielectric layer formation on the surface of a glass substrate, it bakes at 500 degreeC-700 degreeC, and the glass frit contained in a composition film for dielectric layer formation sinters and becomes a dielectric layer. In the firing step, the organic substance contained in the dielectric layer-forming composition film is volatilized and decomposed, and the organic component is substantially left in the dielectric layer. By the above method, the display panel front panel of the present invention is obtained.

In this way, after manufacturing a display panel, it is preferable to coat the dielectric layer exposed on the surface with protective films, such as MgO.

In the case of the back plate for PDP, a dielectric layer is formed on the electrode mounting surface of a substrate such as a glass substrate in the same manner as above, and then, ribs (barrier ribs) and phosphor layers are formed by a known method. Back plate is obtained. In the case of the back plate, the electrode is preferably an address electrode.

The film thickness of the dielectric layer of the front plate after a baking process is 5-20 micrometers, Preferably it is 5-15 micrometers, More preferably, it is 10-15 micrometers. Since the crack does not generate | occur | produce by shrinkage | contraction of the composition for dielectric layer formation whose film thickness after baking is 20 micrometers or less, it is preferable. When the film thickness after baking is 5 micrometers or more, since sufficient characteristic as a dielectric layer is acquired, it is preferable. The film thickness of the dielectric layer of the back plate is 5-15 micrometers, Preferably it is 7-12 micrometers. If the film thickness after baking is 15 micrometers or less, since a crack does not generate | occur | produce by shrinkage of the composition for dielectric layer formation, it is preferable. When the film thickness after baking is 5 micrometers or more, since sufficient characteristic as a dielectric layer is acquired, it is preferable. In addition, a film thickness is the thickness from the copper contact surface of a surface.

In the present invention, at least part of any one of the substrate or the electrode on the surface of the dielectric layer side is copper. It is especially preferable that copper is used for an electrode. When the composition for forming a dielectric layer of the present invention is used in the front plate and the back plate of the present invention, fewer bubbles are generated and less bubbles are generated than copper used for at least part of the substrate or the electrode on the surface of the dielectric layer side. Since the island softening point is lower than the firing temperature, bubbles are not mixed in the dielectric layer after firing, and a dielectric layer having high flatness can be obtained. Moreover, by using the composition of this invention, precipitation of the metal which exists in an underlayer (substrate, an electrode) can be suppressed, and the dielectric layer of high quality can be obtained.

Example

EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated in detail based on an Example. In addition, this invention is not limited to the following Example.

Example  1-7, Comparative example  1 to 2

(1) Adjustment of Composition for Dielectric Layer Formation

According to the composition (unit is mass part) shown in following Table 1, it is organic by mixing binder resin which has a hydroxyl group in a side chain, 25 mass parts of dibutyl phthalates as a plasticizer, and 100 mass parts of 3-methoxybutyl acetate as a solvent for 3 hours with a stirrer. The composition for dielectric layer formation was adjusted by kneading 50 mass parts of the organic components (50% of solid content), and 75 mass parts of glass frits after adjusting a component.

(2) Fabrication of sheet-shaped unbaked body for forming dielectric layer for PDP

The obtained dielectric layer-forming composition is applied onto a supporting film made of a silicon-based release polyethylene terephthalate (PET) film (Purex A43: manufactured by Teijin DuPont Film Co., Ltd.) having a thickness of 38 µm using a lip coater, and a coating film is applied. The solvent was completely removed by drying at 100 ° C. for 6 minutes, and a dielectric film-forming composition film having a thickness shown in Table 1 was formed on a support film. Next, a silicon-based release PET film (Purex A24: manufactured by Teijin DuPont Film Co., Ltd.) having a thickness of 25 μm was attached on the composition film for forming a dielectric layer to prepare a sheet-shaped unbaked body for forming a dielectric layer for PDP.

(3) Formation of front plate or back plate for PDP

The following table in which the copper-electrode previously heated at 80 degreeC was peeled off, peeling the silicone type | mold release PET film (Purex A24: Teijin Dupont Film Co., Ltd. product) of the sheet-like unbaked body for PDP dielectric layer formation obtained by (2). The panel of 1 was laminated by the hot roll laminator at 105 degreeC. The air pressure was 3 kg / cm ² , and the lamination speed was 1.0 m / min.

(4) Evaluation of the dielectric layer

After peeling off the silicone type release PET film (Purex A23: made by Teijin Dupont Film Co., Ltd.) which is a support film of the composition film for dielectric layer formation obtained by said (3), based on the following evaluation criteria of a composition film for dielectric layer formation. External appearance was observed. Moreover, surface roughness was measured with the stylus type surface roughness meter. Moreover, in order to evaluate the characteristic after baking, after baking at the temperature increase rate of 6.0 degree-C / min and holding at 580 degreeC for 30 minutes, surface roughness and the film thickness after baking were measured with the stylus type surface roughness meter. In addition, the appearance of the dielectric layer was observed according to the following evaluation criteria regarding the prevention of defects caused by the generation of bubbles, crack resistance and withstand voltage. The evaluation results are shown in Table 1 below.

(Membrane thickness before baking)

Film thickness before firing. Unit μm.

(Front panel or back panel)

The panel formed in the said process (3).

A: front panel

B: back plate

(Appearance observation after supporting film peeling)

A: No defects such as lines and craters were observed.

C: defects such as lines and craters were observed.

(Surface roughness Rmax before firing)

Surface roughness was measured with a tactile surface roughness meter. Unit μm.

(Surface roughness Rmax after firing)

Surface roughness was measured with a tactile surface roughness meter. Unit μm.

(Film thickness after firing)

Film thickness after firing. Unit μm.

(Prevention of the defect by the outbreak of the bubble)

After firing, the appearance was observed.

A: The defect by foaming is not seen.

C: Bubbles remained in the dielectric layer due to the generation of bubbles, and defects were observed.

(Crack prevention)

After firing, the appearance was observed.

A: No crack is seen in the dielectric layer.

C: Cracks were seen in the dielectric layer.

(Withstand voltage)

After firing, the breakdown voltage was measured.

A: The value is stable in plane.

C: In-plane voltage deviation is seen.

week):

(b-1): Binder resin isobutyl methacrylate / hydroxyethyl methacrylate having a hydroxyl group in the side chain = 60/40 (wt%) copolymer (Mw = 15.000)

(b-2): Binder resin isobutyl methacrylate / hydroxyethyl methacrylate = 50/50 (weight%) copolymer which has a hydroxyl group in a side chain (Mw = 15.000)

(b-3): Binder resin isobutyl methacrylate / hydroxyethyl methacrylate = 77/23 (wt%) copolymer having a hydroxyl group in the side chain (Mw = 15.000)

This result shows that, in the dielectric layer using the specific composition of the present invention, the dispersibility of the inorganic powder is good, the flatness after firing, the prevention of defects due to the generation of bubbles, the crack prevention property, and the withstand voltage property are excellent. It shows that the characteristics of the front plate and back plate for the formed PDP are also favorable.

Industrial availability

As described above, in the present invention, the front plate and the back plate for the plasma display panel and the composition used therein can form a dielectric layer having high dispersibility of inorganic powder, uniformity and free of defects such as cracks and lines. It is possible to provide a plasma display panel which enables high quality image display without mis-discharge or point defects.

The amount of hydroxyl groups contained in the side chain in the dielectric layer is converted into the average number of hydroxyl groups contained in the side chain per monomer structural unit and contains 0.4 or more binder resins per monomer structural unit, so that at least the substrate or electrode on the surface of the dielectric layer side In any of the front or back plates of PDP in which copper is present, there is an effect that a front plate and a back plate for a PDP using a dielectric layer having sufficient flatness without bubbles are left in the dielectric layer after firing.

Moreover, when the thickness after baking is set to 5-15 micrometers, it is prevented that a crack arises in a dielectric layer by the heat shrink at the time of baking, and the effect that a front plate and a back plate for PDP using a favorable dielectric layer can be produced.

Furthermore, in the composition for dielectric layer formation for PDP of this invention, the quantity of an inorganic powder and the hydroxyl group contained in a side chain is 0.4 piece per monomer structural unit in conversion into the average number of hydroxyl groups contained in the side chain per monomer structural unit. By containing the binder resin mentioned above, it can be used for manufacture of the sufficiently flat dielectric layer without the crack preferably used for the said front plate and back plate.

Claims (3)

A front plate for a plasma display panel comprising a substrate, a plurality of electrodes formed on the substrate, and at least a dielectric layer formed on the substrate to cover the electrodes. At least a part of either the substrate or the electrode on the surface of the dielectric layer side is copper, and the thickness after firing of the dielectric layer is 5 to 20 µm, The said dielectric layer before baking has (a) an inorganic powder, and (b) a hydroxyl group in a side chain, and the quantity of the hydroxyl group contained in a side chain is converted into the average number of hydroxyl groups contained in a side chain per monomer structural unit, and it consists of 1 monomer A front panel for a plasma display panel, wherein the dielectric layer is for a plasma display panel containing at least 0.4 binder resin per unit. A back plate for a plasma display panel comprising a substrate, a plurality of address electrodes formed on the substrate, and at least a dielectric layer formed on the substrate to cover the address electrodes, At least a portion of the substrate or the address electrode on the surface of the dielectric layer side is copper, and the thickness after firing of the dielectric layer is 5 to 15 µm, The said dielectric layer before baking has (a) an inorganic powder, and (b) a hydroxyl group in a side chain, and the quantity of the hydroxyl group contained in a side chain is converted into the average number of hydroxyl groups contained in a side chain per monomer structural unit, and it consists of 1 monomer A back plate for a plasma display panel, which is a dielectric layer for a plasma display panel containing a binder resin of 0.4 or more per unit. It is possible to form the dielectric layer of Claim 1 or 2, (a) Inorganic powder and (b) Binder resin which has a hydroxyl group in a side chain, and the quantity of the hydroxyl group contained in a side chain is 0.4 or more per 1 monomer structural unit in conversion into the average number of hydroxyl groups contained in a side chain per monomer structural unit. A composition for forming a dielectric layer for a plasma display panel, comprising:

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