JPH0850811A - Photosensitive insulating glass paste - Google Patents

Abstract

PURPOSE:To carry out highly fine and high density display by containing glass powder, acrylic copolymer having carboxyl group and ethylene-type unsaturated group in side chains and in the molecular terminals, a photoreactive compounds, and a photopolymerization initiator. CONSTITUTION:A glass powder having glass transition temperature 350-470 deg.C is preferable. An acrylic copolymer having carboxyl group and ethylene-type unsaturated group in the side chains and in the molecular terminals is used as a polymer binder component. The copolymer is produced by adding the ethylene-type unsaturated group to the side chains or molecular terminals of an acrylic copolymer produced by an unsaturated carboxylic acid and an ethylene-type unsaturated compound. As a photoreactive compound to be used, a compound containing photoreactive C-C unsaturated bonds is used. A photopolymerization initiator is preferably added in 0.15-50wt.% of the total of the acrylic copolymer and the photoreactive compound. As a result, a diaphragm can be formed easily and disorder of the width and peripheral parts can be prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photosensitive insulating glass paste used for forming partition walls (also called barriers, ribs, barrier ribs) or via holes of a plasma display panel (PDP).

[0002]

2. Description of the Related Art Plasma display panels (PD
P) is capable of high-speed display as compared with liquid crystal panels and is easy to be upsized, and thus has permeated into fields such as office automation equipment and public relations display devices. Further, there are great expectations for progress in the field of high-definition television.

With the expansion of such applications, a color PDP having a large number of fine display cells has been receiving attention. The PDP causes a plasma discharge to occur between an anode and a cathode electrode facing each other in a discharge space provided between a front glass substrate and a rear glass substrate, and emits light from a gas sealed in the discharge space. The display is performed. In this case, a partition wall is provided in order to suppress the spread of the discharge to a certain area so that the display is performed in a prescribed cell and to secure a uniform discharge space. Particularly, in a color PDP, in order to prevent erroneous discharge and color bleeding between adjacent cells, to support a pressure difference between inside and outside of the PDP, to limit the spread of discharge within a unit light emitting region, and to reduce the distance between discharge electrodes. A partition wall is formed between the front and rear substrates as a spacer for defining. Further, in a direct current (DC) PDP, a dielectric (also referred to as an insulator) layer is provided for electrode protection in order to prevent discharge current concentration. This dielectric layer is 50-200 μmφ
It is formed by embedding a conductor in the via hole.

The partition wall has a width of about 30 to 80.
The height is 100 μm and the height is 100 to 200 μm, but usually an insulating paste made of glass is printed and dried on the front glass substrate or the rear glass substrate by a screen printing method, and the printing and drying steps are repeated 10 to 20 times to obtain a predetermined amount. It is formed by firing after it has been raised. However, the usual screen printing method has a problem that it is difficult to align the discharge electrode previously formed on the front transparent flat plate with the printing place of the insulating glass paste. Moreover, the overlapping printing of the glass paste is performed 10 to 20 times, so that the side wall edge portions of the partition wall and the wall are wavy and the hem is disturbed, and the height accuracy cannot be obtained, and the via hole of the insulating layer is not obtained. However, there are problems such as poor display quality, poor workability, and low yield.

With the increase in area and resolution of PDPs, such a method by screen printing makes it more technically difficult to manufacture high aspect ratio, high-definition partition walls and fine and uniform via holes. And it is becoming disadvantageous in terms of cost.

As a method for improving these problems, in JP-A-1-296534, JP-A-2-165538, and JP-A-5-342992, partition walls are formed by a photolithography technique using a photosensitive paste. The method of doing is proposed. However, with these methods, a dense film cannot be obtained after firing because the glass content of the photosensitive insulating paste is low, and because the sensitivity and resolution of the photosensitive insulating paste are low, high aspect ratio, high-definition partition walls are used. Therefore, it was necessary to repeat the steps of screen printing, exposure, and development because it could not be obtained. Therefore, there was a limit to reducing the cost.

Further, in JP-A-2-165538, after a photosensitive paste is coated on a transfer paper,
Japanese Patent Laid-Open No. 3-57138 proposes a method of forming partition walls by transferring a transfer film onto a glass substrate, and JP-A-3-57138 proposes a method of filling the grooves of a photoresist layer with a dielectric paste to form partition walls. In addition, JP-A-4-1095
Japanese Patent Laid-Open No. 36-36 proposes a method of forming partition walls using a photosensitive organic film. However, these methods have a limit in reducing the cost because the number of steps is increased because a transfer film, a photoresist, or an organic film is required. Further, there is a problem in obtaining a wall with high definition and high aspect ratio.

[0008]

DISCLOSURE OF THE INVENTION An object of the present invention is to provide a defect such as corrugation of the side edge portions of the partition walls and walls of the conventional insulating paste for thick film printing or photosensitive insulating paste, and disturbance of the hem, or fine defects. It is a photosensitive insulating glass paste that can significantly eliminate the drawback that uniform via holes cannot be manufactured with high precision, and can form via holes of partition walls, walls and fine and uniform insulating layers with high definition and high aspect ratio. To provide. Another object of the present invention is to provide a photosensitive insulating glass paste capable of forming a partition wall for PDP, a wall body and an insulating layer, which can cope with future large screens.

[0009]

The object of the present invention is as follows.
Photosensitivity for plasma display panel characterized by containing glass powder, acrylic copolymer having carboxyl group and ethylenically unsaturated group at side chain or molecular end, photoreactive compound and photopolymerization initiator Achieved by insulating glass paste.

That is, in the present invention, it is important to impart photosensitivity to the insulating glass paste by using a specific photosensitive polymer, which facilitates the formation of partition walls and via holes by using photolithography technology. It can be formed with high accuracy, high aspect ratio, and good workability.

The photosensitive insulating glass paste for a plasma display panel according to the present invention comprises a glass powder, an acrylic copolymer having a carboxyl group and an ethylenically unsaturated group at a side chain or a molecular end, a photoreactive compound and a light. It contains a polymerization initiator.

The glass powder used in the present invention is not particularly limited, and known glass insulating materials can be applied, but glass powder that can be baked at 500 to 610 ° C. is preferable.

Therefore, the glass powder is expressed in terms of oxides: SiO ₂ 3.0 to 60% by weight Al ₂ O ₃ 0.5 to 5% by weight B ₂ O ₃ 5 to 40% by weight Bi ₂ O ₃ 20 to It is preferable to contain 90% by weight or more of those having a composition range of 60% by weight ZnO 2.0 to 40% by weight. Within this range, glass powder that can be baked on a glass substrate at 500 to 610 ° C. can be obtained.

As the composition in the glass powder, SiO ₂ is preferably added in the range of 3.0 to 60% by weight,
If it is less than 3.0% by weight, the denseness, strength and stability of the glass layer will be deteriorated, and the coefficient of thermal expansion will be mismatched with that of the glass substrate, resulting in deviation from the desired values. On the other hand, if it exceeds 60% by weight, the heat resistant temperature increases, and if it is 600 ° C. or less, it becomes difficult to bake it on a glass substrate, and the electrical insulating property decreases.

Al ₂ O ₃ is preferably blended in the range of 0.5 to 5% by weight. If it is less than 0.5% by weight, the strength in the glass phase is lowered. If it exceeds 5% by weight, the heat resistant temperature of the glass becomes too high and it becomes difficult to bake it on a glass substrate. Further, it becomes difficult to obtain a dense insulating layer at a temperature of 600 ° C. or lower.

B ₂ O ₃ is preferably blended in the range of 5 to 40% by weight. B ₂ O ₃ is from 800 to 1 Glass powder
To melt at temperatures near 200 ° C and to Al ₂ O ₃
Even if there is a large amount, the baking temperature of the glass powder is 500 to 610 so as not to impair the electrical, mechanical and thermal properties such as electric insulation, strength, coefficient of thermal expansion, and denseness of the insulating layer.
Formulated to control in the range of ° C. If it is less than 5% by weight, the strength of the insulating layer is lowered, and if it exceeds 40% by weight, the stability of the glass is lowered.

Bi ₂ O ₃ is preferably blended in the range of 20 to 60% by weight. If it is less than 20% by weight, it is less effective in controlling the baking temperature when the paste is baked on the glass substrate. If it exceeds 60% by weight, the heat resistant temperature of the glass becomes too low, making it difficult to bake it on a glass substrate.

ZnO is preferably blended in the range of 2.0 to 40% by weight. If it is less than 2.0% by weight, the effect of improving the denseness of the insulating layer is small. If it exceeds 40% by weight, the baking temperature on the glass substrate becomes too low to be controlled, and the insulation resistance becomes low, which is not preferable.

It is preferable that the glass powder does not contain metal oxides such as Na ₂ O, K ₂ O, BaO and Y ₂ O ₃ which deteriorate the discharge characteristics of plasma. Even when a trace amount is contained, it is desirable that the content is 0.1% by weight or less.

Further, in the glass powder, Li ₂ O, Ca
O, TiO ₂ , ZrO ₂ , BaO and the like can be contained, but the amount thereof is preferably less than 10% by weight.

As a method for producing the glass powder, for example, raw materials SiO ₂ , Al ₂ O ₃ , B ₂ O ₃ , Bi ₂ O ₃ and ZnO are mixed so as to have a predetermined composition, and 90
After melting at 0 to 1200 ° C., it is rapidly cooled to form a glass frit and crushed to a fine powder of about 1.0 to 7 μm. As the raw material, high-purity carbonate, oxide, hydroxide or the like can be used. Depending on the type and composition of the glass powder, 99.99% or more of ultra-high-purity alkoxide or organometallic raw material is used, and if powder produced homogeneously by the sol-gel method is used, high electrical resistance and dense pores It is preferable because a small number of high-strength insulating layers can be obtained.

The glass powder particle diameter used in the above is selected in consideration of the width and height of the partition wall to be produced and the via hole diameter and thickness of the insulating layer, but 50% by weight.
Has a particle size of 1.0 to 7 μm and a specific surface area of 0.2 to 3.0 m ^2.
/ G, and the sphere ratio is preferably 80% by number or more. More preferably, the particle diameter is 1.5 to 5 μm, the specific surface area is 0.25 to 2.0 m ² / g, and the sphericity is 90 number% or more. Within this range, light is sufficiently transmitted during exposure to ultraviolet light, and uniform via holes with no difference in upper and lower hole diameters can be obtained. Particle size less than 1.0 μm, specific surface area 3.0 m ² /
If it exceeds g, the powder becomes too fine and light is scattered during exposure to cure the unexposed portion. For this reason, the hem of the partition wall is disturbed during development and the height accuracy cannot be obtained. In addition, an insulating film having a uniform and rounded via hole cannot be obtained. Further, when the sphericity is less than 80% by number, partition walls having a high definition and a high aspect ratio cannot be obtained due to the influence of scattering by the glass powder during exposure to ultraviolet light.

The glass transition temperature (Tg) of the glass powder is
It is preferably 350 to 470 ° C. Within this range, when the glass substrate is baked in the range of 500 to 610 ° C., organic substances such as polymers and monomers are completely decomposed, and bulging of partition walls does not occur, which is preferable.

The acrylic copolymer having a carboxyl group and an ethylenically unsaturated group at the side chain or at the molecular end used in the present invention is a polymer binder component (photosensitive polymer) and comprises an unsaturated carboxylic acid and an ethylenic group. It can be produced by adding an ethylenically unsaturated group to a side chain or a molecular end of an acrylic copolymer formed by copolymerizing with an unsaturated compound. Preferred is
It has a carboxyl group and an ethylenically unsaturated group in the side chain.

Specific examples of unsaturated carboxylic acids include:
Examples thereof include acrylic acid, methacrylic acid, itaconic acid, crotonic acid, maleic acid, fumaric acid, vinyl acetic acid, and acid anhydrides thereof. On the other hand, specific examples of the ethylenically unsaturated compound include methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, and n-butyl acrylate. Butyl methacrylate, sec-butyl acrylate, sec-butyl methacrylate, isobutyl acrylate, isobutyl methacrylate, tert-butyl acrylate, t
Examples thereof include, but are not limited to, ert-butyl methacrylate, n-pentyl acrylate, n-pentyl methacrylate, styrene, p-methylstyrene, o-methylstyrene, m-methylstyrene and the like. A copolymer having good thermal decomposability can be obtained by including at least methyl methacrylate from the above ethylenically unsaturated compounds as the main polymerization component of these acrylic main chain polymers.

Examples of the ethylenically unsaturated group at the side chain or the terminal of the molecule include vinyl group, allyl group, acryl group and methacryl group. As a method of adding such a side chain to an acrylic polymer, there is a method of making an addition reaction of an ethylenically unsaturated compound having a glycidyl group with a carboxyl group in an acrylic polymer or an acrylic acid chloride compound.

Examples of the ethylenic unsaturated compound having a glycidyl group include glycidyl acrylate, glycidyl methacrylate, allyl glycidyl ether, glycidyl ethyl acrylate, crotonyl glycidyl ether, crotonic acid glycidyl ether, and isocrotonic acid glycidyl ether. . Examples of acrylic acid chloride compounds include acrylic acid chloride, methacrylic acid chloride, and allyl chloride. The addition amount of these ethylenically unsaturated compounds or acrylic acid chloride compounds is preferably 0.05 to 1 molar equivalent, and more preferably 0.1 to 0.8 molar equivalent to the carboxyl group in the acrylic polymer. . If the addition amount is less than 0.05 equivalent, the photosensitive characteristics become poor and it becomes difficult to form a pattern. When the addition amount is larger than 1 molar equivalent, the solubility of the developer in the unexposed area is lowered and the hardness of the coating film is lowered, which is not preferable.

The acid value (AV) of the acrylic polymer having a carboxyl group and an ethylenically unsaturated group at the side chain or molecular end thus obtained is preferably 50 to 180, more preferably 70 to 140. . More preferably, it is 80-120. When the acid value is less than 50, the amount of ethylenically unsaturated groups increases, and the ratio of photosensitive carboxyl groups decreases, so that the development allowable range is narrow, and the hem of the partition pattern and the via hole of the insulating layer are narrowed. In formation, it becomes impossible to form a via hole having L (thickness) / D (via hole diameter) of 1 or more. Further, when the acid value exceeds 180, the solubility of the unexposed area in the developing solution is lowered. Therefore, when the developing solution concentration is increased, peeling occurs even in the exposed area, and a partition wall having a high definition and a high aspect ratio is formed. It becomes difficult to obtain. In addition, the hardness of the coating film decreases. Further, in the polymer having the above preferable acid value, the sharper the molecular weight distribution of the polymer is, the more the developing characteristics are improved and the finer partition wall is obtained, which is preferable.

The photosensitive insulating paste of the present invention may contain a photosensitive polymer or a non-photosensitive polymer other than the above acrylic copolymer as a polymer binder component.

The photosensitive polymer includes a photo-insolubilizing type and a photo-solubilizing type. As the photo-insolubilizing type, a functional monomer or oligomer having one or more unsaturated groups in one molecule is used. Mixed with a suitable polymer binder, aromatic diazo compound, aromatic azide compound,
A mixture of a photosensitive compound such as an organic halogen compound with a suitable polymer binder, a photosensitive polymer obtained by pendant to an existing polymer with a photosensitive group, or a modified one thereof, a diazo amine Light-soluble types such as so-called diazo resins such as condensates with formaldehyde include diazo compound inorganic salts and complexes with organic acids, quinonediazos mixed with a suitable polymer binder, and quinonediazos. With a suitable polymer binder, such as phenol, naphthoquinone 1,2 of novolac resin
-Diazide-5-sulfonic acid ester and the like. The proportion of the acrylic copolymer having a carboxyl group and an ethylenically unsaturated group at the side chain or molecular end contained in the photosensitive polymer binder component is preferably at least 5% by weight, more preferably 20% by weight or more. is there. When the content of the acrylic copolymer is less than 5% by weight, the effect of expanding the development allowable width is small, and the developability is liable to be lowered, which makes it difficult to form a sharp pattern in the skirt of the partition wall, which is not preferable.

As the non-photosensitive polymer, polyvinyl alcohol, polyvinyl butyral, methacrylic acid ester polymer, acrylic acid ester polymer, acrylic acid ester-methacrylic acid ester copolymer, α-methylstyrene polymer, butyl methacrylate resin, etc. Can be given.

As the photoreactive compound used in the present invention, a compound containing a carbon-carbon unsaturated bond having photoreactivity can be used. Specific examples thereof include allyl acrylate and 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, isobonyl acrylate, 2-hydroxypropyl acrylate, isodexyl acrylate, isooctyl acrylate, lauryl acrylate, 2-methoxyethyl acrylate , Methoxy ethylene glycol acrylate, methoxy diethylene glycol acrylate, octa fluorosilicone pentyl acrylate, phenoxyethyl acrylate, stearyl acrylate, trifluoroethyl acrylate, allyl or cyclohexyl diacrylate, bisphenol A diacrylate, 1,4
Butanediol diacrylate, 1,3-butylene glycol diacrylate, ethylene glycol diacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, polyethylene glycol diacrylate, dipentaerythritol hexaacrylate, dipentaerythritol Monohydroxypentaacrylate, ditrimethylolpropane tetraacrylate, glycerol diacrylate, methoxy or cyclohexyl diacrylate, neopentyl glycol diacrylate, propylene glycol diacrylate, polypropylene glycol diacrylate, triglycerol diacrylate, Trimethylolpropane triacrylate and the above acrylate changed to methacrylate, - methacryloxypropyl trimethoxysilane, and 1-vinyl-2-pyrrolidone. In the present invention, these may be used alone or in combination of two or more.

The acrylic copolymer having a carboxyl group and an ethylenically unsaturated group at the side chain or molecular end is usually used in an amount of 0.1 to 10 times the weight of the photoreactive compound. If the amount of the acrylic copolymer is too small, the viscosity of the slurry becomes small, and the uniformity of dispersion in the slurry may be deteriorated. On the other hand, if the amount of the acrylic copolymer is too large, the solubility of the unexposed area in the developer becomes poor.

Specific examples of the photopolymerization initiator used in the present invention include benzophenone, methyl o-benzoylbenzoate, 4,4-bis (dimethylamine) benzophenone, 4,4-bis (diethylamino) benzophenone,
4,4-dichlorobenzophenone, 4-benzoyl-4
-Methyldiphenylketone, dibenzylketone, fluorenone, 2,2-diethoxyacetophenone, 2,2-
Dimethoxy-2-phenyl-2-phenylacetophenone, 2-hydroxy-2-methylpropiophenone, p
-T-butyldichloroacetophenone, thioxanthone, 2-methylthioxanthone, 2-chlorothioxanthone, 2-isopropylthioxanthone, diethylthioxanthone, benzyl, benzyldimethylketanol,
Benzyl-methoxyethyl acetal, benzoin,
Benzoin methyl ether, benzoin butyl ether, anthraquinone, 2-t-butyl anthraquinone,
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-Butadione-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, Michler-ketone, 2-methyl- [4- (methylthio) phenyl]- Two
-Morpholino-1-propanone, naphthalenesulfonyl chloride, quinolinesulfonyl chloride, N-phenylthioacridone, 4,4-azobisisobutyronitrile, diphenyl disulfide, benzthiazole disulfide, triphenylmorphine, camphorquinone, tetrabromine Examples thereof include a combination of a photoreducing dye such as carbon dioxide, tribromophenyl sulfone, benzoin peroxide and eosin, and methylene blue with a reducing agent such as ascorbic acid and triethanolamine. In the present invention, these may be used alone or in combination of two or more.

The photopolymerization initiator is used in an amount of 0.1 to 50% by weight based on the sum of the acrylic copolymer having a carboxyl group and an ethylenically unsaturated group at the side chain or molecular end and the photoreactive compound. It is preferably added, and more preferably 2 to 25% by weight. If the amount of the photopolymerization initiator is too small, the photosensitivity becomes poor, and if the amount of the photopolymerization initiator is too large, the residual rate of the exposed area may be too small.

In the present invention, it is preferable to add an ultraviolet absorber for the formation of via holes in the partition walls, walls and insulating film. A high aspect ratio, high definition, and high resolution can be obtained by adding a light absorber having a high ultraviolet absorption effect.

That is, in general, the glass powder alone is photo-cured to an excessive portion, and even if it is developed, the partition wall or the via hole cannot be formed, or the roundness largely decreases. As a result of diligent investigations by the present inventors regarding this cause, it has been found that the cause is that scattered ultraviolet light is absorbed or weakened and reaches the light-shielded portion by the exposure mask. Therefore, by adding the ultraviolet light absorber, the scattering of the scattered light is substantially avoided, the hardening of the photosensitive resin in the mask portion is prevented, and the pattern corresponding to the exposure mask is formed.

As the ultraviolet light absorber, those composed of organic dyes are preferably used, and among them, organic dyes having a high UV absorption coefficient in the wavelength range of 350 to 450 nm are preferably used. Specifically, azo dyes, aminoketone dyes, xanthene dyes, quinoline dyes, aminoketone dyes, anthraquinone dyes, benzophenone dyes,
Diphenyl cyanoacrylate type, triazine type, p-
Aminobenzoic acid dyes can be used. Even when an organic dye is added as a light absorber, it does not remain in the insulating film after firing, and the deterioration of the insulating film characteristics due to the light absorber can be suppressed, which is preferable. Among these, azo and benzophenone dyes are preferable.

Typical examples of azo dyes include:
Sudan Blue (C ₂₂ H ₁₈ N ₂ O ₂ = 342.4
), Sudan R (C ₁₇ H ₁₄ N ₂ O ₂ = 278.31), Sudan I
I (C ₁₈ H ₁₄ N ₂ O = 276.34), Sudan III (C ₂₂ H ₁₆
N ₄ O = 352.4), Sudan IV (C ₂₄ H ₂₀ N ₄ O = 380.4)
5) 、 Oil Orange SS 、 CH ₃ C _{6
H 4 N: NC 10 H 6} OH = 262.31), Oil Violet _{(Oil Violet, C 24 H 21} N 5 = 379.46), Oil Yellow _{OB (Oil Yellow OB, CH 3} C 4 H 4 N: NC 10
H ₄ NH ₂ = 261.33).

Examples of benzophenone dyes include Ubinal D-50 (C ₁₃ H ₁₀ O ₅ = 246.22,2,2 ', 4,4
′ -Tetrahydroxybenzophenone), Ubinal MS40 (C ₁₄ H ₁₂ O ₆ S = 308,2-hydroxy-)
4-methoxybenzophenone 5-sulfonic acid), Uvinul _{DS49 (C 15 H 12 O 11} S 2 Na 2 = 478, 2,
2-dihydroxy-4,4′-dimethoxybenzophenone 5,5′-sodium disulphonate) and the like.

The amount of the organic dye added is such that high-definition partition walls and wall bodies having a high aspect ratio can be formed.
The circularity of the via hole of the insulating layer is high, and the difference in the diameter of the via hole between the upper part and the lower part after the via hole is formed is small, and the range is 0.05 with respect to the glass powder. ~ 1 wt% is preferred. 0.0
If it is less than 5% by weight, the effect of adding an ultraviolet absorber decreases,
If the amount is more than wt%, the amount of the light absorber is too large and when irradiated with ultraviolet rays, it will be absorbed by the glass powder before reaching the lower part, and it is not possible to obtain high aspect ratio and high definition partition walls, and formation of via holes. It is not preferable because it becomes defective. More preferably, it is 0.1 to 0.3% by weight.

As a method of adding the ultraviolet light absorber composed of an organic dye, the following method is preferable. That is, a solution in which an organic dye is previously dissolved in an organic solvent is prepared. Next, glass powder is mixed in the organic solvent and dried while stirring. By this method, a so-called capsule-shaped glass powder in which the surface of each glass powder is uniformly coated with an organic dye film can be produced.

In the present invention, there is a preferred range of integrated value of absorbance (wavelength measurement range; 350 to 450 nm).
The integrated value of the absorbance is measured in a powder state, and is measured for a glass powder whose surface is coated with an organic dye.

In the present invention, the absorbance is defined as follows. That is, using a commercially available spectrophotometer, light is applied to a measurement sample in an integrating sphere, and the light reflected there is collected and detected. Further, except for the light detected by the integrating sphere, all the light is regarded as absorbed light and is calculated from the following formula.

The light intensity of the control light is Ir, (Before measuring the absorbance of the sample, BaSO ₃ of the same material as the material coated on the inner surface of the integrating sphere is attached to the sample stage and the light intensity by reflection is measured. Data) The light intensity of the light incident on the sample is I, and the light intensity of the absorbed component after hitting the sample is Io, the light intensity of the reflected component from the sample is represented by (I-Io), and the absorbance Is defined as in equation (1) below. In the above, the unit of light intensity is W / cm ²
Express with. Absorbance = -log ((I-Io) / Ir) Absorbance is measured as follows. 1. 20mm diameter of powder with light absorber added,
Mold to a size of 4 mm. 2. Next, a spectrophotometer is used to attach a powder molding to the attachment port of the reflecting sample of the integrating sphere, and the absorbance due to the reflected light is measured in the wavelength range of 200 to 650 nm. A graph as shown in FIG. 1 is obtained. The vertical axis represents the absorbance of formula (1), and the horizontal axis represents the measurement wavelength. 3. Next, in FIG.
It is divided into 10 sections for each m, and the area for each section is obtained. The area is calculated as follows. For example, assuming that the absorbance at 350 nm is 0.75, the absorbance at 360 nm is 0.80, the absorbance at 370 nm is 0.85, the absorbance at 440 nm is 0.60, and the absorbance at 450 nm is 0.55. , And the area of the 350 to 360 nm portion is A, and is regarded as a trapezoid, A is calculated as follows. Area A = (0.75 + 0.80) × 10/2 = 7.75 Similarly, Area B is Area B = (0.80 + 0.85) × 10/2 = 8.25 .... Similarly, Area J is Area J = (0.60 + 0.55) × 10/2 = 5.75. The integrated value S of the area of 10 sections is obtained as follows. S = A + B + ... + J The area S was defined as the integrated value of the absorbance at 350 to 450 nm.

In the present invention, the preferable range of the integrated value of the above-mentioned absorbance is 20 to 80, and the further preferable range is 30.
-60. If the absorbance is less than 20, the light will be scattered by the glass powder before being sufficiently transmitted to the bottom of the insulating layer during ultraviolet exposure, and the unexposed portion will be cured.
A partition wall having a high aspect ratio and a high definition, and a via hole having a roundness with no difference in hole diameter between the upper and lower holes cannot be formed. On the other hand, if the absorbance exceeds 80, the light is absorbed by the glass powder before reaching the lower part of the insulating layer, and the light does not pass through to the lower insulating layer, so that the light cannot be cured. As a result, peeling occurs during development, and it becomes difficult to form good barrier ribs and via holes.

In the present invention, P contained in the glass powder
Metals such as b, Fe, Cd, Mn, Co, and Mg and their oxides react with the carboxyl groups of the photosensitive polymer contained in the paste to cause the paste to gel in a short time and become lumps that cannot be printed as a paste. There are cases. It is presumed that this is an ionic cross-linking reaction of the photosensitive polymer, but in order to prevent such cross-linking reaction, not only the photo-sensitive polymer but also the photoreactive compound, the photopolymerization initiator or the plasticizer is adversely affected. It is preferable to prevent the gelation by adding a compound (stabilizer) that does not give That is, the powder is surface-treated with a compound having an effect such as complexation with a metal or oxide powder which causes a gelation reaction or salt formation with an acid functional group to stabilize the photosensitive insulating glass paste. A triazole compound is preferably used as such a stabilizer. Among the triazole compounds, benzotriazole works particularly effectively.

The surface treatment of the glass powder with a triazole compound such as benzotriazole is preferably performed as follows. That is, after dissolving a predetermined amount of benzotriazole with respect to glass powder in an organic solvent such as methyl acetate, ethyl acetate, ethyl alcohol, and methyl alcohol, 1 to 24 of the solution is added to the solution so that the powder can be sufficiently immersed. Soak for hours. After immersion, preferably 20 to 3
The powder is naturally dried at 0 ° C., the solvent is evaporated, and a triazole-treated powder is prepared.

The ratio of the stabilizer used in the present invention (stabilizer / glass powder) is preferably 0.2 to 4% by weight, more preferably 0.4 to 3% by weight. 0.
If it is less than 2% by weight, it is ineffective in preventing the crosslinking reaction of the polymer and gels in a short time. On the other hand, if it exceeds 4% by weight, the amount of the stabilizer becomes too large and it becomes difficult to remove the binder such as the polymer, the monomer and the stabilizer during the firing of the insulating paste in the non-oxidizing atmosphere. The characteristics deteriorate.

Further, even if a small amount of water is present in the photosensitive insulating glass paste, it promotes gelation of the insulating paste. To prevent this, the glass powder is 120-150.
It is preferable to dry at 5 ° C. for 5 to 15 hours to sufficiently remove water, as gelation can be prevented.

In the present invention, the photosensitive insulating glass paste contains a sensitizer, a thermal polymerization inhibitor, a plasticizer, an antioxidant, a sensitization aid, a thickener, a dispersant, an organic or inorganic precipitation inhibitor, etc. Is preferably added.

The sensitizer is added to improve high sensitivity. Specific examples of the sensitizer include 2,4-diethylthioxanthone, isopropylthioxanthone and 2,3-
Bis (4-diethylaminobenzal) cyclopentanone, 2,6-bis (4-dimethylaminibenzal) cyclohexanone, 2,6-bis (4-dimethylaminobenzal) -4-methylcyclohexanone, Michler-ketone, 4,4, -bis (diethylamino) -benzophenone, 4,4-bis (dimethylamino) chalcone, 4,4
-Bis (diethylamino) chalcone, p-dimethylaminocinnamylideneindanone, p-dimethylaminobenzylideneindanone, 2- (p-dimethylaminophenylvinylene) -isonaphthothiazole, 1,3- ^ bis (4-dimethyl) Aminobenzal) acetone, 1,3-carbonyl-bis (4-diethylaminobenzal) acetone, 3,3-carbonyl-bis (7-diethylaminocoumarin), N-phenyl-N-ethylethanolamine, N-phenylethanol Amine, N-tolyldiethanolamine, N-phenylethanolamine, dimethylaminobenzoic acid isoamyl, diethylaminobenzoic acid isoamyl, 3-phenyl-5-benzoylthio-tetrazoleazole, 1-phenyl-5-ethoxycarbonylthio-tetrazo And the like. In the present invention, these may be used alone or in combination of two or more. Some sensitizers can also be used as photopolymerization initiators. When the sensitizer is added to the photosensitive insulating glass paste of the present invention, the addition amount is the sum of the acrylic copolymer having a carboxyl group and an ethylenically unsaturated group at the side chain or molecular end and the photoreactive compound. On the other hand usually 0.1-3
It is 0% by weight, more preferably 0.5 to 15% by weight.
If the amount of the sensitizer is too small, the effect of improving the photosensitivity is not exhibited, and if the amount of the sensitizer is too large, the residual ratio of the exposed area may be too small.

The thermal polymerization inhibitor is added to improve the thermal stability during storage. Specific examples of the thermal polymerization inhibitor include hydroquinone, N-nitrosodiphenylamine, phenothiazine, pt-butylcatechol, N-.
Phenylnaphthylamine, 2,6-di-t-butyl-p
-Methylphenol, chloranil, pyrogallol and the like. When the thermal polymerization inhibitor is added, the addition amount is usually 0.1 to 0.1 with respect to the sum of the acrylic copolymer having an ethylenically unsaturated group at the side chain or the molecular end and the photoreactive polymerizable compound. 20% by weight, more preferably 0.
It is 5 to 10% by weight. If the amount of the thermal polymerization inhibitor is too small, the effect of improving the thermal stability during storage will not be exhibited, and if the amount of the thermal polymerization inhibitor is too large, the residual rate of the exposed portion may be too small. is there.

Specific examples of the plasticizer include dibutyl phthalate, dioctyl phthalate, polyethylene glycol and glycerin.

The antioxidant is added to prevent oxidation of the acrylic copolymer during storage. Specific examples of the antioxidant include 2,6-di-t-butyl-p-cresol, butylated hydroxyanisole, 2,6-di-t.
-4-ethylphenol, 2,2-methylene-bis-
(4-methyl-6-t-butylphenol), 2,2-
Methylene-bis- (4-ethyl-6-t-butylphenol), 4,4-tibis- (3-methyl-6-t-butylphenol), 1,1,3-tris- (2-methyl-)
6-t-butylphenol), 1,1,3-tris-
(2-methyl-4-hydroxy-t-butylphenyl)
Butane, bis [3,3-bis- (4-hydroxy-3-
t-Butylphenyl) butyric ascid] glycol ester, dilauryl thiodipropionate, triphenyl phosphite and the like. When the antioxidant is added, its amount is usually relative to the total amount of the inorganic powder, the acrylic copolymer having an ethylenically unsaturated group at the side chain or the molecular end, the photoreactive compound and the photopolymerization initiator. It is 0.01 to 5% by weight, more preferably 0.1 to 1% by weight. If the amount of the antioxidant is small, the effect of preventing the oxidation of the acrylic copolymer during storage cannot be obtained, and if the amount of the antioxidant is too large, the residual ratio of the exposed area may be too small.

The composition of the photosensitive insulating glass paste is preferably selected within the following range.

(A) Glass powder; (a),
80 to 96% by weight relative to the sum of (b) (b) Acrylic copolymer having a carboxyl group and an ethylenically unsaturated group at the side chain or molecular end and a photoreactive compound; (a), (b) 20 to 4% by weight relative to the sum (c) Photopolymerization initiator; 2 to 25% by weight relative to (b) (d) UV absorber; 0.05 to based on (a)
2 wt% More preferably in the above, the composition of the components (a), (b) and (d) is 86 to 92 wt% and 14 to 92% by weight, respectively.
8% by weight, and 0.1 to 0.8% by weight. Within this range, ultraviolet rays are well transmitted during exposure, the photo-curing function is fully exerted, and the generation of residual film in the unexposed area during subsequent development can be almost eliminated, resulting in a high aspect ratio and high definition. It is possible to form a via hole having a high degree of partition and a high roundness. Further, there is an advantage that the insulating layer after firing becomes dense and a film having high insulation resistance can be obtained.

The photosensitive insulating glass paste of the present invention is prepared by dissolving an acrylic copolymer having a carboxyl group and an ethylenically unsaturated group at a side chain or a molecular end and a photopolymerization initiator in a photoreactive compound to prepare a solution. It can be produced by dispersing an ultraviolet absorber in the. When the acrylic copolymer and the photopolymerization initiator do not dissolve in the photoreactive compound, or when it is desired to adjust the viscosity of the solution, a mixed solution of the acrylic copolymer, the photopolymerization initiator and the photoreactive compound You may add the organic solvent which can melt | dissolve. Examples of the organic solvent used at this time include methyl cellosolve, ethyl cellosolve, butyl cellosolve, methyl ethyl ketone, dioxane, acetone, cyclohexanone, cyclopentanone, isobutyl alcohol, isopropyl alcohol, tetrahydrofuran, dimethyl sulfoxide, γ-butyrolactone and the like. An organic solvent mixture containing one or more of the above is used.

Furthermore, if necessary, an organic solvent, a sensitizer, a thermal polymerization inhibitor, a plasticizer, an antioxidant, a sensitization aid, a thickener,
A dispersant and an organic or inorganic precipitation inhibitor are added to form a slurry of the mixture. A slurry prepared to have a predetermined composition is uniformly dispersed by a three-roller or a kneader to prepare a paste.

The viscosity of the paste is appropriately adjusted by the addition ratio of glass powder, thickener, organic solvent, plasticizer, suspending agent, etc., but the range is 2000 to 200,000 cp.
It is preferably s (centipoise). For example, when the glass substrate is applied by a spin coating method other than the screen printing method, 2000 to 5000 cps is preferable. Apply once by screen printing method and film thickness 10 ~ 20μ
In order to obtain m, 50,000 to 200,000 cps is preferable.

Next, an example of a method of forming a via hole in a partition wall or an insulating layer using the photosensitive insulating glass paste of the present invention will be described, but the present invention is not limited to this.

First, in the case of a partition wall, on a front glass substrate on which a transparent electrode such as ITO is formed, when a via hole is formed in an insulating layer, on the glass substrate, a photosensitive insulating glass is applied by a screen printing method or the like. Apply paste and dry. In addition to the printing method, the coating film is formed by the bar coater method,
It can be performed by a known method such as a roll coater method. Here, when the paste is applied on the glass substrate, the surface treatment of the substrate may be performed in order to enhance the adhesion between the substrate and the coating film. The surface treatment liquid may be a silane coupling agent such as vinyltrichlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, tris- (2-methoxyethoxy).
Vinylsilane, γ-glycidoxypropyltrimethoxysilane, γ- (methacryloxypropyl) trimethoxysilane, γ- (2-aminoethyl) aminopropyltrimethoxysilane, γ-chloropropyltrimethoxysilane, γ-mercaptopropyltri Methoxysilane, γ-
Aminopropyltriethoxysilane and the like, or organic metals such as organic titanium, organic aluminum and organic zirconium, and organic solvents such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, methyl alcohol, ethyl alcohol, propyl alcohol and butyl alcohol. It is possible to use one diluted to a concentration of 0.1 to 5%. After applying this surface treatment liquid evenly on the substrate with a spinner or the like, 80
The surface treatment can be performed by drying at ˜140 ° C. for 10 to 60 minutes.

The coating thickness of the insulating layer and the partition wall depends on the number of coatings,
It can be adjusted by selecting the screen mesh and the viscosity of the paste, but it is 30 to 300 μm. It is preferably 30 to 150 m. If the thickness is less than 30 μm, it is difficult to keep a dense film homogeneous and have high electrical insulation.
On the other hand, when the thickness exceeds 150 μm, it is difficult for ultraviolet rays to pass through to the lower part in one exposure with ultraviolet rays, peeling occurs during development, and it becomes impossible to form partition walls or insulating layers. For bulkheads,
Usually, the width is 40 to 60 μm, the height is 100 to 300 μm, and the pitch is 150 to 250 μm, so it is difficult to form this thickness by one printing, and printing and drying are repeated 5 to 10 times.

In the case of the insulating paste of the present invention, in forming the via hole of the insulating layer, there is no difference in the upper and lower hole diameters, and the insulating layer can be finely and uniformly formed, and the preferable thickness range for making the insulating layer dense is 20 to 150 μm. Within this range, there is an advantage that a via hole having a diameter of 30 to 150 μm can be formed without causing a difference in upper and lower hole diameters. Although the resolution of the via hole varies depending on the thickness of the insulating layer, it is preferable that the aspect ratio (thickness of insulating film / vial diameter) is 1 or less because ultraviolet rays are sufficiently transmitted. When the thickness is 60 μm, it is preferable to form a via hole having a diameter of 60 μm.

A film of paste applied on the substrate (including a partition and an insulating layer for forming a via hole is referred to as an applied film)
Is dried at 70 to 120 ° C. for several minutes to 1 hour to evaporate the solvents and form an insulating film.

Next, in order to further improve the sensitivity,
It is preferable to form a PVA film on the surface of the insulating film.
The PVA film is formed by using PVA with a concentration of 0.5 to 5% by weight.
The solution is uniformly applied onto the substrate by a method such as a spinner and then dried at 70 to 90 ° C. for 10 to 60 minutes to evaporate water. Further, it is preferable to add a small amount of alcohol to the aqueous solution of PVA because the wettability with the insulating film is improved and evaporation is facilitated. A more preferable PVA solution concentration is 1 to 3% by weight. Within this range, the sensitivity is further improved. It is estimated that the reason why the PVA coating improves the sensitivity is as follows. That is, when the photosensitive polymer and the monomer are photo-cured, it is considered that oxygen in the air interferes with the sensitivity of photo-curing, but the presence of the PVA film can block excess oxygen, so the sensitivity is improved during exposure. . In addition to PVA, a water-soluble and transparent polymer such as cellulose-based methyl cellulose can also be used.

After forming a film of PVA or the like as needed, an exposure and development process is performed. The exposure is performed by a normal photomask method. After selective exposure by a photolithography method, development is performed to remove the uncured portion (negative type), and predetermined partition walls and via holes are formed.

Examples of the active light source used at the time of exposure include ultraviolet rays, electron beams, and X-rays. Among these, ultraviolet rays are preferable, and the light source is, for example, a low pressure mercury lamp, a high pressure mercury lamp, a halogen lamp, A germicidal lamp can be used. Among these, the ultra-high pressure mercury lamp is preferable. The exposure conditions vary depending on the thickness of the partition walls and the insulating layer, but the exposure is performed for 1 to 30 minutes using an ultrahigh pressure mercury lamp with an output of 5 to 100 mW / cm ² .

After exposure, development is carried out using a developing solution. In this case, dipping or spraying can be used. As the developing solution, an organic solvent capable of dissolving the mixture of the acrylic copolymer having a carboxyl group and an ethylenically unsaturated group at the side chain or molecular end, the photoreactive compound and the photopolymerization initiator can be used. Further, water may be added to the organic solvent within the range in which the dissolving power is not lost. Further, since the side chain of the acrylic copolymer has a carboxyl group, it can be developed with an alkaline aqueous solution. As the alkaline aqueous solution, a metallic alkaline aqueous solution such as sodium hydroxide or calcium hydroxide aqueous solution can be used, but it is preferable to use the organic alkaline aqueous solution because the alkaline component can be easily removed during firing. Specific examples of the organic alkali include
Examples thereof include tetramethylammonium hydroxide, trimethylbenzylammonium hydroxide, monoethanolamine and diethanolamine. The concentration of the alkaline aqueous solution is usually 0.01 to 10% by weight, more preferably 0.1 to 5% by weight. If the alkali concentration is too low, the unexposed area is not removed. If the alkali concentration is too high, the pattern area may be peeled off and the exposed area may be corroded.

When the partition wall is formed, its height is 1
Since the thickness is from 0.00 to 300 μm, a high-definition partition wall may not be obtained by one exposure and development. At this time,
The coating is formed to a thickness of 50 to 100 μm, and the non-exposed portion is masked and exposed. Further, one of the features of the photosensitive insulating glass paste of the present invention is that the printing, drying, and exposing steps are repeated several times for stacking, and finally, batch development is performed to form partition walls having a required height.

In the process of preparing, printing, exposing and developing the photosensitive insulating glass paste of the present invention, it is necessary to perform it at a place where ultraviolet rays can be blocked. If this is not done, the paste or coating film will be photo-cured by ultraviolet rays, and it will not be possible to obtain partition walls or insulating films that can exhibit the effects of the present invention.

Next, firing is performed in a firing furnace to form partition walls and insulating layers. The firing temperature varies depending on the glass substrate and the type of conductor such as silver, silver-palladium, or gold previously formed on the glass substrate, but firing is usually performed in air. In the case of a glass substrate or silver conductor, 1 at a temperature of 520 to 610 ° C.
It is held for 0 to 60 minutes to form a partition wall and an insulating layer.

[0073]

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited thereto. In the following examples, all parts are by weight unless otherwise specified.

A. Glass powder component The glass composition is SiO ₂ ; 27.5%, Al ₂ O ₃ ;
2.8%, B ₂ O ₃ ; 14%, Bi ₂ O ₃ ; 47.8
%, ZnO; 2.6%, ZrO ₂ ; 4.8%, Na
₂ O; 0.5%. The glass powder was finely powdered in advance with an attritor and then spheroidized in a plasma stream to give an average particle diameter of 2.6 μm and a specific surface area of 0.92 m ² / g.
A powder having a sphericity of 95% by number was used. The measurement of sphericity is
The powder was photographed with an optical microscope at 300x magnification, of which the countable particles were counted and the ratio of spherical ones was expressed.

The glass composition is SiO ₂ ; 6.5%, A
l ₂ O ₃ ; 1.8%, B ₂ O ₃ ; 30%, Bi ₂ O ₃ ;
35.5%, ZnO; 25.4%, Na ₂ O; 8%. The glass powder was made into fine powder with an attritor in advance and then spheroidized in a plasma stream to give an average particle size of 3.5.
A powder having a particle size of μm, a specific surface area of 0.62 m ² / g and a sphericity of 92% by number was used.

B. UV absorber Organic dye; Azo dye; Sudan, chemical formula: C ₂₄ H ₂ ON ₄ O, molecular weight: 380.45.

Organic Dyes; Benzophenone Dyes; Ubinard D-50, Chemical Formula; C ₁₃ H ₁₀ O ₅ , Molecular Weight; 24
6.22.

C. Polymer binder 40% methacrylic acid (MAA), 30% methyl methacrylate (MMA) and 30% styrene (S
Polymer in which 0.4 equivalent (corresponding to 40%) of glycidyl methacrylate (GMA) is added to the carboxyl group (MAA) of the copolymer of t). The acid value of the polymer was 95.

D. Monomer Trimethylol propane triacrylate E.I. Solvent γ-butyrolactone (γ-BL) F.I. Photopolymerization initiator 2-methyl-1- [4- (methylthio) phenyl] -2
-Morpholinopropanone-1 and 2,4-diethylthioxanthone were added in an amount of 20% by weight based on the total amount of the polymer and the monomer.

G. Sensitizer 2,4-diethylthioxanthone (added in the same proportion as the photopolymerization initiator).

H. Photopolymerization accelerator p-Dimethylaminobenzoic acid ethyl ester (EPA)
(Addition of half of photopolymerization initiator) I. Plasticizer Dibutyl phthalate (DBP) J.I. Thickener 4% SiO ₂ concentration 15% dissolved in 2- (2-butoxyethoxy) ethyl acetate was added to the polymer.

<Production of Insulating Paste> A. Preparation of Organic Vehicle A solvent and a polymer binder were mixed so as to form a 50% solution and heated to 120 ° C. with stirring to uniformly dissolve all the polymer binders. Then, the solution was cooled to room temperature, and a photopolymerization initiator, a sensitizer and a photopolymerization accelerator were added and dissolved. The solution was then filtered using a 400 mesh filter.

B. Preparation of Powder with Added Light Absorber A predetermined amount of an organic dye was weighed, a dispersant was added to a solution dissolved in isopropyl alcohol (IPA), and the mixture was uniformly stirred with a homogenizer. Next, a predetermined amount of glass powder is added to this solution, and the mixture is uniformly dispersed and mixed, and then dried at a temperature of 150 to 200 ° C. using a rotary evaporator,
The IPA was evaporated. Thus, a powder in which the surface of the glass powder was uniformly coated with the organic dye film (so-called capsule treatment) was prepared. Integrated value of powder absorbance (3
Table 1 shows the results of measurement for 50 to 450 nm).

C. Preparation of Insulating Paste To prepare the paste, a photoreactive compound, a powder with a light absorber added (glass encapsulated with an organic dye), a thickener and a plasticizer were added to the above organic vehicle so as to have a predetermined composition. It was prepared by mixing and dispersing with this roller. The prepared composition is shown in Table 1.

[0085]

[Table 1] D. Surface Treatment of Glass Substrate As a surface treatment liquid, a 1% by weight solution of (2-aminoethyl) aminopropyltrimethoxysilane in isopropyl alcohol is used. Next, 1.0 ml of this solution was dropped onto a glass substrate (10 inches x 10 inches x 2.0 mm thickness), coated with a spinner at a rotation speed of 3000 rpm for 10 seconds, and then held at 100 ° C for 30 minutes to dry. Then, the surface treatment was performed.

E. Formation of partition walls and via holes In order to form partition walls, an insulating paste was printed on the above glass substrate using a 325 mesh screen. Printing and drying were repeated 4 times to adjust the film thickness in order to avoid the occurrence of pinholes in the coating film. Drying on the way was performed at 80 ° C. for 10 minutes. Then, at 80 ℃ 4
It was held for 0 minutes and dried to form an insulating film for partition walls having a thickness of 70 μm.

The insulating film for forming the via hole was applied in the same manner as above to form an insulating film having a thickness of 60 μm.

F. Exposure / development The formation of the barrier rib is performed by applying L on the barrier rib film prepared in E above.
Using a negative type chrome mask having (line) 60 μm, S (space) 160 μm, and pitch 220 μm,
Ultraviolet exposure was carried out from the upper surface with an ultrahigh pressure mercury lamp with an output of 2000 mJ / cm ² . Subsequently, the exposed film was exposed to ultraviolet rays using the same chrome mask as above for the insulating film whose thickness was adjusted to 180 μm by repeating printing and drying under the above conditions E. Further, the steps of printing, drying, exposing and drying were repeated to form an insulating film for partition walls having a height of 200 μm. Then 2
Dip in a 0.5% by weight aqueous solution of monoethanolamine held at 5 ° C for development, and then wash the non-photocured space portion with water using a shower spray and remove to form striped partition walls. did.

The formation of the via holes was performed by using a chrome mask having 5000 via holes each having a diameter (φ) of 60 μm on the insulating paste film and using the chrome mask from the top surface to 1000 mJ /
Ultraviolet exposure was carried out with an ultrahigh pressure mercury lamp having a cm ² output. Then 25
It was immersed in a 0.5% by weight aqueous solution of monoethanolamine maintained at 0 ° C. for development, and thereafter, the non-photocured via holes were washed with water using a spray.

H. Baking The glass substrate having the partition walls and via holes obtained in the above F was baked in air at 585 ° C. for 20 minutes to prepare an insulating layer having partition walls and via holes.

J. Evaluation With respect to the glass substrate on which the partition wall was formed, the skirt disorder of the partition wall, the accuracy of the line width, the shape of the cross section, and the accuracy of the space width were measured and evaluated. The roundness of the via hole, the difference between the upper and lower hole diameters, and the shape of the inner surface of the hole were measured and evaluated for the glass substrate on which the via hole was formed. The results are shown in Table 1.

The barrier ribs manufactured using the insulating paste of the present invention are excellent in that the width of the barrier ribs is hardly disturbed, the line width is ± 2 μm, the cross section is rectangular, and the barrier rib height accuracy is ± 5 μm. It was The insulating film with the via hole has a high roundness of the via hole, and the difference in hole diameter between the upper part and the lower part is ± 10.
%, And formed uniformly over all holes.

Comparative Example 1 Using the glass powders among the above glass powders, powder composition 53%, acrylate resin 10%, toluene 24%,
Isopropyl alcohol 8% and dibutyl phthalate 5% were mixed and dispersed with three rollers to prepare an insulating paste.

Next, by a screen printing method, a 325 mesh screen was used to form L on a 20 inch square glass substrate.
(Line width); 60 μm, space; 160 μm, pitch;
A stripe-shaped partition wall having a height of 220 μm and a height of 200 μm was formed. The partition wall having a height of 200 μm was formed by performing overprinting 15 times.

For the formation of the via holes, a screen having 150 μmφ via holes of 5,000 holes was used, and the glass substrate was overcoated with the insulating paste 5 times in the same manner as above to form an insulating film having a thickness of 60 μm.

Subsequently, the glass substrate on which the partition walls and via holes were formed was baked by holding it in air at 585 ° C. for 30 minutes.

In the obtained partition wall, many waviness and hem disturbance were observed at the side edge portions. Further, since it was necessary to repeat the process of printing and drying the insulating paste 15 times, the tolerance of the pitch was as large as ± 50 μm with respect to ± 8 μm, which greatly exceeded the limit of the tolerance. In addition, the accuracy of partition wall height and workability were low.

The insulating layer having the via holes is
The pore diameter was non-uniform and the roundness was poor, and it could not be used as an insulating layer for PDP.

[0099]

EFFECTS OF THE INVENTION Since the present invention has the above-mentioned structure, it is extremely easy to form the partition walls, and the width and hem are not disturbed, and the height is uniform, and high definition, high aspect ratio and high accuracy can be achieved.
Further, fine via holes can be formed reliably and accurately on a large-sized substrate. Therefore, the plasma display panel (PDP) using the barrier ribs and via holes formed by using the photosensitive insulating paste of the present invention enables high definition, high display quality, and high density display. Further, it is possible to easily achieve a large PDP of 40 inches or more.

Claims (6)

[Claims] 1. A plasma display comprising glass powder, an acrylic copolymer having a carboxyl group and an ethylenically unsaturated group at a side chain or a molecular end, a photoreactive compound and a photopolymerization initiator. -Photosensitive insulating glass paste for panels. 2. 50% by weight of the glass powder has a particle size of 1.
~ 7 μm, specific surface area 0.2-3.0 m ² / g, sphericity 8
The photosensitive insulating glass paste according to claim 1, which has a size of 0% by number or more. 3. A glass powder, SiO ₂ 3.0 to 60 wt% Al ₂ O ₃ 0.5 to 5 wt% B ₂ O ₃ 5 to 40 wt% Bi ₂ O ₃ 20 to 60 in terms of oxide title 2. The photosensitive insulating glass paste according to claim 1, containing 90% by weight or more of a composition range of ZnO 2.0 to 40% by weight. 4. The photosensitive insulating glass paste according to claim 1, which contains an ultraviolet absorber. 5. The photosensitive insulating glass paste according to claim 4, wherein the ultraviolet absorber is an organic dye. 6. The photosensitive insulating glass paste according to claim 4, wherein the integrated value of the absorbance of the ultraviolet light absorber at 350 to 450 nm is 30 to 100.