JPH0896711A - Phosphor pattern forming method - Google Patents

Abstract

PURPOSE: To form a phosphor pattern excellent in close adhesiveness and shape stability by applying a cross linking agent to a substrate surface, laminating a phosphor-contained photosensitive resin composition layer on this applied surface, and performing exposure through a pattern mask. CONSTITUTION: A cross linking agent is applied to a surface of a glass substrate provided with a conductive circuit of an ITO film. As this cross linking agent, any of a silane compound, aluminum compound and a titanate compound is preferable. A phosphor-contained photosensitive resin composition layer is applied by a liquid state or preformed into a film, pasted and laminated to this cross linking agent applied surface. Next on this photosensitive layer, a pattern mask is provided by dry film resist and exposed by applying an ultraviolet ray. Thereafter, the mask is removed, to perform developing by an alkali diluted water solution, further to perform burning at about 500 to 550 deg.C, and to fix a phosphor. In this way, a high accurate phosphor pattern, excellent in adhesiveness with the glass substrate and in stability of pattern shape, is formed in good workability.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming a phosphor pattern for a fluorescent display, and more specifically, a fluorescent display such as a plasma display panel (PDP), a liquid crystal display device, a fluorescent display device, a hybrid integrated circuit or the like. The present invention relates to a method for forming a phosphor pattern that is useful when manufacturing a body.

[0002]

2. Description of the Related Art Recently, various flat panel displays have been actively developed, and among them, PDPs have attracted attention.
In the future, the application will be expanded from the display screen of a laptop computer to various electronic bulletin boards and further to a so-called "wall TV". The cells of the display panel of the PDP are coated with phosphors for color display, and the phosphors develop color by the ultraviolet rays generated by the enclosed gas in the cells due to the applied voltage. As a method of applying this phosphor, a method of applying a slurry liquid of a photoresist in which phosphors of respective colors are dispersed by screen printing (Japanese Patent Application Laid-Open No. HEI-1)
-115027, JP-A-1-124928), a method of pouring the slurry liquid into the cell (JP-A-2-155142), and the like have been tried.

[0003]

However, in the above method, since the liquid photoresist containing the phosphor is directly applied to the glass substrate, the glass substrate and the photoresist or the glass substrate and the phosphor after the development are separated from each other. Adhesion is not sufficient, and the phosphor may fall off under long-term use or severe use conditions, resulting in a problem that a good pattern shape cannot be obtained.

[0004]

Means for Solving the Problems The inventors of the present invention have conducted extensive studies as a solution to such problems, and as a result, in forming a phosphor pattern for a fluorescent display, a cross-linking agent was previously applied to the substrate surface. After that, by stacking a phosphor-containing photosensitive resin composition layer and then performing exposure through a pattern mask, excellent adhesion between the glass substrate and the phosphor-containing photosensitive resin composition or the phosphor after development is excellent. Also, the stability of the pattern shape of the phosphor formed by firing is excellent,
Furthermore, if the phosphor-containing photosensitive resin composition is used as a photoresist film in advance and then the phosphor pattern is formed as described above, there is less variation in brightness than the liquid resist, excellent pattern formation accuracy, and workability. It was found to be good, and the present invention was completed. The present invention is described in detail below.

The cross-linking agent used in the present invention is a compound having a function of chemically bonding an inorganic material and an organic material, which is generally called a coupling agent, specifically, a silane compound. There is a silane coupling agent, an aluminum coupling agent that is an aluminum compound, and a titanate coupling agent that is a titanate compound.
As the silane coupling agent, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, β -(3,4 epoxy cyclohexyl)
-Epoxysilanes such as -ethyltrimethoxysilane, β- (3,4 epoxycyclohexyl) -ethyltriethoxysilane, N-β (aminoethyl) γ-aminopropyltrimethoxysilane, N-β (aminoethyl) γ- Aminopropyltriethoxysilane, N-β (aminoethyl)
γ-aminopropyldimethoxysilane, N-β (aminoethyl) γ-aminopropylmethyldiethoxysilane,
Examples include aminosilanes such as γ-aminopropyltriethoxysilane and N-phenyl-γ-aminopropyltrimethoxysilane, and methacryloxysilanes such as γ-methacryloxypropyltrimethoxysilane and γ-methacryloxypropyltriethoxysilane. Examples of the coupling agent include acetoalkoxyaluminum diisopropylate and the like, and examples of the titanate coupling agent include isopropyltriisostearoyl titanate. Above all, it is preferable to use a silane-based coupling agent such as epoxysilane or aminosilane in that the pattern shape during development is good.

Two or more of these coupling agents can be used in combination. The phosphor-containing photosensitive resin composition layer of the present invention comprises a composition in which a phosphor is mixed with a photosensitive resin composition, and the photosensitive resin composition comprises a base polymer (A) and an ethylenically unsaturated compound. (B) and a photopolymerization initiator (C). As the base polymer (A), acrylic resins, polyester resins, polyurethane resins and the like are used, and among these,
An acrylic copolymer having (meth) acrylate as a main component and optionally an ethylenically unsaturated carboxylic acid or another copolymerizable monomer is important. An acetoacetyl group-containing acrylic copolymer can also be used.

Examples of the (meth) acrylic acid ester include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, hexyl (meth) acrylate, and 2
-Ethylhexyl (meth) acrylate, cyclohexyl (meth) acrylate, benzyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, glycidyl (meth) acrylate and the like are exemplified. It

As the ethylenically unsaturated carboxylic acid, monocarboxylic acids such as acrylic acid, methacrylic acid and crotonic acid are preferably used, and in addition, dicarboxylic acids such as maleic acid, fumaric acid and itaconic acid, or their anhydrides. A thing and a half ester can also be used. Among these, acrylic acid and methacrylic acid are particularly preferable. When the dilute alkali developing type is used, ethylenically unsaturated carboxylic acid is contained in an amount of about 15 to 30% by weight (acid value of 100 to 2).
It is necessary to copolymerize (about 00 mgKOH / g).
Examples of other copolymerizable monomers include acrylamide, methacrylamide, acrylonitrile, methacrylonitrile, styrene, α-methylstyrene, vinyl acetate, alkyl vinyl ether and the like.

As the ethylenically unsaturated compound (B),
Ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, butylene glycol di (meth) acrylate, neopentyl Glycol di (meta)
Acrylate, 1,6-hexane glycol di (meth)
Acrylate, trimethylolpropane tri (meth) acrylate, glycerin di (meth) acrylate, pentaerythritol di (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol penta (meth) acrylate, 2,2-bis (4 -(Meth) acryloxydiethoxyphenyl) propane, 2,2-bis- (4- (meth) acryloxypolyethoxyphenyl) propane, 2-hydroxy-3-
(Meth) acryloyloxypropyl (meth) acrylate, ethylene glycol diglycidyl ether di (meth) acrylate, diethylene glycol diglycidyl ether di (meth) acrylate, phthalic acid diglycidyl ester di (meth) acrylate, glycerin polyglycidyl ether poly (meth ) Examples include polyfunctional monomers such as acrylate. An appropriate amount of a monofunctional monomer may be used together with these polyfunctional monomers.

Examples of monofunctional monomers are 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate and 2-phenoxy-2-hydroxypropyl (meth) acrylate. , 2- (meth) acryloyloxy-2-hydroxypropyl phthalate, 3-chloro-2-hydroxypropyl (meth) acrylate,
Examples thereof include glycerin mono (meth) acrylate, 2- (meth) acryloyloxyethyl acid phosphate, half (meth) acrylate of a phthalic acid derivative, and N-methylol (meth) acrylamide.

The ratio of the ethylenically unsaturated compound (B) to 100 parts by weight of the base polymer (A) is 10 to 20.
It is desirable to select from 0 part by weight, particularly 40 to 100 parts by weight. An insufficient amount of the ethylenically unsaturated compound (B) leads to poor curing, a decrease in flexibility, and a delay in the developing rate. An excessive amount of the ethylenically unsaturated compound (B) increases the tackiness, cold flow, and peeling of the cured resist. This leads to a decrease in speed.

Further, as the photopolymerization initiator (C), benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin n-butyl ether, benzoin phenyl ether,
Benzyl diphenyl disulfide, benzyl dimethyl ketal, dibenzyl, diacetyl, anthraquinone, naphthoquinone, 3,3′-dimethyl-4-methoxybenzophenone, benzophenone, p, p′-bis (dimethylamino) benzophenone, p, p′-bis (diethylamino) ) Benzophenone, p, p'-diethylaminobenzophenone, pivaloin ethyl ether, 1,1-dichloroacetophenone, p-t-butyldichloroacetophenone, hexaarylimidazole dimer, 2,2 '
-Bis (o-chlorophenyl) 4,5,4 ', 5'-tetraphenyl-1,2'-biimidazole, 2-chlorothioxanthone, 2-methylthioxanthone, 2,4-
Diethylthioxanthone, 2,2'-diethoxyacetophenone, 2,2'-dimethoxy-2-phenylacetophenone, 2,2'-dichloro-4-phenoxyacetophenone, phenylglyoxylate, α-hydroxyisobutylphenone, dibezosparone, 1 -(4-Isopropylphenyl) -2-hydroxy-2-methyl-1
-Propanone, 2-methyl- [4- (methylthio) phenyl] -2-morpholino-1-propanone, tribromophenyl sulfone, tribromomethylphenyl sulfone and the like are exemplified. At this time, the total mixing ratio of the photopolymerization initiator (C) is about 1 to 20 parts by weight based on 100 parts by weight of the total amount of the base polymer (A) and the ethylenically unsaturated compound (B). Appropriate.

The phosphor (D) to be incorporated in the phosphor-containing photosensitive resin composition is not particularly limited, but a phosphor having a rare earth oxyhalide or the like as a base material and the base material activated with an activator is used. Preferably, for example, as the ultraviolet excitation type phosphor, Y ₂ O ₃ : Eu, YVO ₄ : Eu, (Y, Gd)
BO ₃ : Eu (above red), Zn ₂ GeO ₂ : Mn, Ba
_{Al 12 O 19: Mn, Zn} 2 SiO 4: Mn, LaPO 4:
Tb (above green), Sr ₅ (PO ₄ ) ₃ CI: Eu, Ba
MgAl ₁₄ O ₂₃ : Eu, BaMgAl ₁₆ O ₂₇ : Eu (above blue), and the like. Other phosphors include Y ₂
O ₃ S: Eu, γ-Zn ₃ (PO ₄ ) ₂ : Mn, (ZnC
d) S: Ag + In ₂ O ₃ (above red), ZnS: Cu,
Al, ZnS: Au, Cu, Al, (ZnCd) S: C
u, Al, Zn ₂ SiO ₄ : Mn, As, Y ₃ Al ₅ O ₁₂ :
Ce, Gd ₂ O ₂ S: Tb, Y ₃ Al ₅ O ₁₂ : Tb, Zn
O: Zn (above green), ZnS: Ag + red pigment, Y ₂
SiO ₃ : Ce (above blue) or the like can also be used.

A phosphor (D) is added to the photosensitive resin composition of the present invention.
There is no particular limitation on the method of blending the above-mentioned compound, and a known method such as adding a predetermined amount of the phosphor (D) to the above-mentioned photosensitive resin composition and mixing and stirring the mixture to make the phosphor (D) uniform. There is a method of dispersing. Phosphor (D) in this case
1 to 50 parts by weight, more preferably 10 to 30 parts by weight, based on 100 parts by weight of the total amount of the base polymer (A) and the ethylenically unsaturated compound (B) in the photosensitive resin composition. Is. In addition to the phosphor-containing photosensitive resin composition of the present invention, other dyes (coloring, coloring), adhesion promoters, plasticizers, antioxidants, thermal polymerization inhibitors, solvents,
Additives such as a surface tension modifier, a stabilizer, a chain transfer agent, an antifoaming agent, and a flame retardant can be added as appropriate.

In forming the phosphor-containing photosensitive resin composition layer of the present invention, it is of course possible to use the above-mentioned phosphor-containing photosensitive resin composition as a liquid resist, but the dispersion stability of the phosphor is stable. In consideration of the properties, uniformity of coating thickness, storage stability, workability, etc., the resin composition is formed into a film in advance to obtain a dry film resist laminate (photoresist film). It is advantageous to form the layer on the surface of the substrate for patterning. Further, examples of the glass substrate for forming a pattern using the resin composition include a glass substrate having electrodes, a glass substrate having glass partition walls, a ceramic substrate having electrodes, and the like. Among them, PDP production It is particularly useful for a so-called ITO film substrate which is a glass substrate on which electrodes used at times are arranged. Hereinafter, a method for producing a dry film resist laminate using the phosphor-containing photosensitive resin composition of the present invention and a phosphor pattern forming method using the same will be described.

(Preparation of Laminate for Dry Film Resist) After coating the above phosphor-containing photosensitive resin composition on the surface of a base film such as polyester film, polypropylene film, polystyrene film, etc., a polyethylene film is applied on the coated surface. Then, a protective film such as a polyvinyl alcohol film is coated to obtain a dry film resist laminate. The film thickness of the photosensitive resin composition at this time varies depending on the content of the phosphor (D) and the structure of PDP or the like and cannot be generally stated, but is usually 10 to 200.
It is preferably selected from among μm. (Lamination on glass substrate) The greatest feature of the present invention is
Before laminating the dry film resist on a glass substrate, a cross-linking agent (coupling agent) is applied to the surface (laminating surface) of the substrate in advance. The compound is sprayed by applying a solution or dispersion of about 0.1 to 5% by weight dissolved or dispersed in an organic solvent such as water, ethanol, methanol, isopropyl alcohol, benzene, toluene, xylene, or acetone. Method, screen printing method, roll coater method, or other known method. The coating thickness is suitably selected from 0.001 to 1 μm.

(Exposure) To form an image with a dry film resist, the adhesive force between the base film and the photosensitive resin composition layer and the adhesive force between the protective film and the photosensitive resin composition layer are compared, After peeling off the film having the lower adhesive strength, the photosensitive resin composition layer side is adhered to the anode fixing surface of the front glass, for example, in the case of a PDP using a transmission type panel, and then the other side The pattern mask is brought into close contact with the above film and exposed. At this time, two or more dry film resists can be laminated if necessary. Further, when the photosensitive resin composition does not have tackiness, the other film may be peeled off, and then the pattern mask may be brought into direct contact with the photosensitive resin composition layer for exposure. The exposure is usually carried out by irradiation with ultraviolet rays, and as the light source at that time, a high pressure mercury lamp, an ultrahigh pressure mercury lamp, a carbon arc lamp, a xenon lamp, a metal halide lamp, a chemical lamp and the like are used. After irradiation with ultraviolet rays, heating can be performed as necessary to achieve complete curing.

(Development) After the exposure, the film on the resist is peeled off and then developed. Since the phosphor-containing photosensitive resin composition of the present invention is a dilute alkali developing type, the development after exposure is carried out with an alkali 1 such as sodium carbonate or potassium carbonate.
It is performed using a dilute aqueous solution of about 2% by weight. (Firing) The cell-formed substrate after the above treatment is 500 to 550 ° C.
Is baked to fix the phosphor (D) inside the cell. In this way, the phosphor (D) can be fixed on the glass substrate. In order to form a full color PDP, red, blue and green phosphors (D) are used.
It can be produced by repeating the above (exposure) to (baking) using a photoresist film containing a.

Further, it is also possible to fix the phosphor (D) using the photoresist film of the present invention to a flat substrate for a PDP in which cells are formed in advance by glass partition walls (reflection type panel). For example, the photoresist film of the present invention was laminated on the flat substrate for PDP, and pressed from above with a mold or the like having a convex shape that matches the concave shape of the cell, and the photoresist film was made to follow the cell shape. After that, the phosphor (D) can be fixed inside the cell by the above steps of (exposure) to (baking). At this time, since flexibility is required for the photoresist film, it is preferable to use a flexible film such as polyvinyl alcohol, nylon, or cellulose as the base film or the protective film.

[0020]

According to the method of forming a phosphor pattern of the present invention, a phosphor-containing photosensitive resin composition layer is laminated on the surface of a substrate coated with a silane compound in advance, and then exposed through a pattern mask. And the phosphor-containing photosensitive resin composition or the phosphor after development are excellent in adhesion, and the stability of the pattern shape of the phosphor formed by baking is also excellent, and thus PDP, fluorescent display device, hybrid integrated circuit, etc. Can be used when manufacturing the fluorescent display of,
Very useful for DP production.

[0021]

EXAMPLES The present invention will be specifically described below with reference to examples. In the examples, "%" and "parts" mean weight basis unless otherwise specified. Example 1 (Adjustment of dope) 46 parts of the following base polymer (A),
A resin composition was prepared by mixing 54 parts of the following ethylenically unsaturated compound (B), 8 parts of the photogravimetric initiator (C) having the following formulation, and 26 parts of the following phosphor (D). Base polymer (A) methyl methacrylate / n-butyl methacrylate / 2
-A copolymer in which the copolymerization ratio of ethylhexyl acrylate / methacrylic acid is 55/8/15/22 on a weight basis (acid value 143.3, glass transition point 66.3 ° C, weight average molecular weight 80,000).

The mixture light weight 20/10/6 ethylenically unsaturated compound (B) trimethylolpropane triacrylate / polyethylene glycol (600) dimethacrylate / ethylene oxide-modified phthalic acid acrylate (manufactured by Kyoeisha Yushi Kogyo Co., Ltd.) Polymerization initiator (C) benzophenone / p, p′-diethylaminobenzophenone / 2,2-bis (o-chlorophenyl) 4,5,
4 ', 5'-tetraphenyl-1,2' mixture phosphor bicycloalkyl weight ratio 8 / 0.15 / 1 imidazole (D) (Y, Gd) BO 3: Eu / Zn 2 SiO 4: Mn / Ba
MgAl ₁₄ O ₂₃ : Eu ²⁺ = 33/50/17 (weight ratio)
Blend (average particle size: 4 ± 2μm)

(Preparation of Dry Film) The dope described above was applied to a thickness of 20 using an applicator with a gap of 4 mils.
Coating on μm polyester film, 1 min 3 at room temperature
After leaving it for 0 second, it was dried in an oven at 60 ° C., 90 ° C. and 110 ° C. for 3 minutes each to give a dry film having a resist thickness of 20 μm (however, a protective film was not provided). (Lamination on glass substrate) Glass substrate (with a thickness of 0.
I having a conductive circuit of about 1 to 0.2 μm formed on the surface
TO film substrate, 200 mm × 200 mm × 2 mm) surface is coated with γ-glycidoxypropyltrimethoxysilane (ethanol solution having a solid content of 1%) as a coupling agent (crosslinking agent), dried and heated to 110 ° C in an oven. , 60
After reaching 0 ° C., the above dry film was laminated at a laminating roll temperature of 100 ° C., the same roll pressure of 3 kg / cm ² , and a laminating speed of 1.5 m / sec.

(Exposure, development) After laminating, 20
The resist surface was exposed to 40 mj with a 3 kW ultra-high pressure mercury lamp using an exposure machine HMW-532D manufactured by Oak Manufacturing Co., Ltd. on the resist surface so as to form an exposed portion having a pitch of 0 μm square and up / down / left / right 260 μm pitch. After a hold time of 15 minutes after exposure, development was carried out at 20 ° C. using a 1% Na ₂ CO ₃ aqueous solution for 1.5 times the minimum development time. (Baking) In the baking oven after development, from room temperature to 550 ° C 1
The resin content was burned up by raising the temperature over time. The evaluation details and the evaluation criteria are shown below.

A. Luminance A PDP panel was produced using the above-mentioned glass substrate, and the luminance of the phosphor portions at the four corners and the center at a total of 5 places was measured with a spot luminance meter, and the variation and the average luminance were examined. b. Storage stability The above dry film is allowed to stand for 1 month in the dark at 40 ° C. and 60% RH, and then (lamination on a glass substrate) to (baking) is carried out in the same manner as above to obtain the variation in brightness and the average brightness. Examined. c. The phosphor pattern (200 μm square) after the adhesive firing was observed with an SEM (scanning electron microscope) to examine the height (μm) of the edge (corner) of the phosphor pattern lifted from the glass substrate. The evaluation criteria are as follows. ◎ --- No lift is observed at all ○ --- Lifting height is less than 10 μm × --- Lifting height is 10 μm or more

Examples 2 to 5 In Example 1, γ-glycidoxypropyltrimethoxysilane was replaced with γ-glycidoxypropylmethyldiethoxysilane (Example 2), β- (3,4 epoxycyclohexyl). ) -Ethyltrimethoxysilane (Example 3), N-β (aminoethyl) γ-aminopropyltrimethoxysilane (Example 4), N-phenyl-γ-aminopropyltrimethoxysilane (Example 5) The same evaluation as in Example 1 was carried out except that Comparative Example 1 The same evaluation as in Example 1 was performed, except that the coupling agent (crosslinking agent) was not applied in Example 1. Comparative Example 2 The same evaluation as in Example 1 was performed except that polyvinyl alcohol (10% aqueous solution) was used in place of γ-glycidoxypropyltrimethoxysilane in Example 1.
Table 1 shows the evaluation results of the examples and comparative examples.

[0027]

[Table 1] Item a Item b Item c Item Variance Average Variance Average Example 1 3 35 3 35 ◎ Example 2 3 30 30 3 29 ◎ Example 3 5 28 4 29 29 ◎ Example 4 5 28 5 28 28 ○ Example 5 4 28 4 29 ○ Comparative Example 1 5 25 5 23 × Comparative Example 2 10 10 7 11 × Note) The variations in the items a and b are the difference between the maximum value and the minimum value of the measured values at 5 points and the average. Represents the average value of the measured values at 5 points, and these units are cd / m ² .

[0028]

The method of forming a phosphor pattern of the present invention comprises laminating a phosphor-containing photosensitive resin composition layer on the surface of a substrate coated with a crosslinking agent such as a silane coupling agent in advance,
Since it is exposed through a pattern mask after that, the adhesion between the glass substrate and the phosphor-containing photosensitive resin composition or the phosphor after development is excellent, and the stability of the pattern shape of the phosphor formed by firing is also excellent. It is excellent and can be used at the time of manufacturing a fluorescent display such as a PDP, VFD (fluorescent display device), and a hybrid integrated circuit, and is very useful particularly for manufacturing a PDP using an ITO film substrate.

Claims (4)

[Claims] 1. In forming a phosphor pattern for a fluorescent display, a phosphor-containing photosensitive resin composition layer is laminated on the surface of a substrate coated with a cross-linking agent and then exposed through a pattern mask. Characteristic phosphor pattern forming method. 2. The phosphor pattern forming method according to claim 1, wherein the crosslinking agent is any one of a silane compound, an aluminum compound and a titanate compound. 3. The phosphor pattern forming method according to claim 1, wherein the substrate is a glass substrate on which electrodes are arranged. 4. The phosphor-containing photosensitive resin composition is formed into a film in advance.
The method for forming a phosphor pattern according to any one of claims.