JP2006030853A - Photosensitive paste and baked product pattern formed using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a photosensitive paste which can be patterned with high definition and in which crystallization of a photopolymerization initiator occurs hardly during low-temperature storage even in the case of a small amount of a solvent, and to provide a baked product pattern formed using the same. <P>SOLUTION: The photosensitive paste contains (A) inorganic fine particles, (B) an organic component containing a photopolymerizable compound and (C) 2-dimethylamino-2-(4-methylbenzyl)-1-(4-morpholinophenyl)butanone as a photopolymerization initiator. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a photosensitive paste useful for forming a fine electrode pattern, a black matrix, and a partition pattern on a plasma display panel (hereinafter abbreviated as PDP) and a fired product pattern formed using the same. .

The PDP is a flat display that displays images and information using light emission by plasma discharge, and is classified into a DC type and an AC type according to a panel structure and a driving method. The principle of color display by this PDP is that plasma discharge is generated in a cell space (discharge space) between opposing electrodes formed on the front glass substrate and the back glass substrate separated by ribs (partition walls), and each cell The phosphor formed on the inner surface of the rear glass substrate is excited by ultraviolet rays generated by the discharge of a gas such as He or Xe enclosed in the space to generate visible light of the three primary colors.
Hereinafter, it will be briefly described with reference to the accompanying drawings.

FIG. 1 partially shows an example of the structure of a surface discharge PDP having a full color display and a three-electrode structure. On the lower surface of the front glass substrate 1, there are a large number of a pair of display electrodes 2a and 2b, each of which has a predetermined pitch, consisting of a transparent electrode 3a or 3b for discharging and a bus electrode 4a or 4b for reducing the line resistance of the transparent electrode. It is lined up. On these display electrodes 2a and 2b, a transparent dielectric layer 5 (low melting point glass) for accumulating charges is formed by printing and baking, and a protective layer (MgO) 6 is deposited thereon. . The protective layer 6 has a role of protecting the display electrode, maintaining a discharge state, and the like. On the other hand, on the rear glass substrate 11, striped ribs (partitions) 12 partitioning the discharge space and a large number of address electrodes (data electrodes) 13 arranged in each discharge space are arranged in a predetermined pitch. Yes. Further, phosphor films of three colors of red (14a), blue (14b), and green (14c) are regularly arranged on the inner surface of each discharge space, and in full color display, red, blue as described above. The three primary colors of phosphor films 14a, 14b, and 14c constitute one pixel.
In the PDP having the above structure, an alternating pulse voltage is applied between the pair of display electrodes 2a and 2b to cause discharge between the electrodes on the same substrate.
Further, in the PDP having the above structure, the ultraviolet rays generated by the discharge excite the phosphor films 14a, 14b and 14c of the rear substrate 11, and the generated visible light is viewed through the transparent electrodes 3a and 3b of the front substrate 1. It has become.

  In recent years, in a PDP having such a structure, higher density and higher definition are required in pattern processing in order to improve image quality. Therefore, patterning by photolithography has been performed.

  In order to realize such high-definition patterning by photolithography, α-aminoalkylphenone-based 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) butanone is used as a photopolymerization initiator. It has been proposed to be effective (see Patent Documents 1 and 2).

However, this photopolymerization initiator has low solubility in a solvent and crystallizes when the photosensitive paste is stored at a low temperature. As a result, when the photosensitive paste is used in this state, there is a problem that a formed pattern is not uniform or pinholes are generated. For this reason, it is necessary to leave the photosensitive paste at room temperature for a long time or to stir the photosensitive paste for a long time to dissolve the crystals, resulting in a decrease in workability.
Moreover, since the solubility with respect to a solvent is low, there also existed a problem that the amount of solvents to be used increased and environmental impact was large.

Japanese Patent Laid-Open No. 10-269848 (Claims) JP-A-10-72240 (Claims)

  Therefore, the present invention has been made to solve such problems of the prior art, and its main purpose is to enable high-definition pattern processing, and a photopolymerization initiator during low-temperature storage even with a small amount of solvent. It is an object of the present invention to provide a photosensitive paste that hardly causes crystallization.

As a result of earnest research for the realization of the above object, the inventor has completed an invention having the following contents.
That is, the photosensitive paste of the present invention comprises (A) inorganic fine particles, (B) an organic component containing a photopolymerizable compound, and (C) 2-dimethylamino-2- (4-methylbenzyl) as a photopolymerization initiator. It is characterized by containing -1- (4-morpholinophenyl) butanone.
Such a photosensitive paste of the present invention may be in the form of a paste, or may be in the form of a dry film previously formed into a film.
Furthermore, according to the present invention, there is provided a PDP in which an electrode pattern, a black matrix pattern, a partition wall pattern and the like are formed from such a fired product of the photosensitive paste.

  As described above, according to the photosensitive paste of the present invention, since the photopolymerization initiator excellent in solubility in a solvent is used, the crystallization of the photopolymerization initiator during low-temperature storage can be achieved even with a small amount of solvent. It is possible to provide a photosensitive paste that hardly occurs. As a result, high-definition pattern processing becomes possible. Moreover, according to the photosensitive paste of the present invention, it is possible to improve workability by shortening the stirring time and reduce the environmental load by reducing the amount of solvent. Furthermore, because of its excellent solubility, it is suitable for dry films with a small amount of solvent.

The photosensitive paste of the present invention uses 2-dimethylamino-2- (4-methylbenzyl) -1- (4-morpholinophenyl) butanone having excellent solubility in a solvent as a photopolymerization initiator. Has the biggest feature. As a result, it is possible to provide a photosensitive paste that hardly causes crystallization of the photopolymerization initiator during low-temperature storage even with a small amount of solvent.
The mixing ratio of such a photopolymerization initiator is suitably 1 to 30 parts by mass, preferably 5 to 20 parts by mass per 100 parts by mass of the resin component in the organic component (B) containing the photopolymerizable compound. is there.

Hereinafter, each component of the photosensitive paste of the present invention will be described.
Examples of the inorganic fine particles (A) include at least one selected from glass fine particles, inorganic fillers, black pigments, and conductive powders.
Among these, the glass fine particles mainly include glass having a glass transition point (Tg) of 300 to 500 ° C. and a glass softening point (Ts) of 400 to 600 ° C., such as lead oxide, bismuth oxide, zinc oxide or lithium oxide. Glass as a component can be preferably used. From the viewpoint of resolution, it is preferable to use glass powder having an average particle size of 10 μm or less, preferably 5 μm or less.

As a black pigment, it is used when black is required for the firing pattern, and a black pigment made of one or more metal oxides such as Co, Ni, Cu, Fe, Mn, Al, and Ru is added. Can do. It is desirable to use fine particles having an average particle diameter of 2 μm or less, preferably 0.1 to 1 μm. This is because if the average particle diameter is smaller than 2 μm, a dense fired film can be formed without impairing adhesion and the like even with a small amount of addition, and sufficient blackness can be obtained. On the other hand, when the average particle diameter of the black pigment is larger than 2 μm, the denseness of the fired film is deteriorated, and the blackness is easily lowered. On the other hand, if the thickness is smaller than 0.1 μm, the hiding power is lowered and a transparent feeling may appear.
The blending amount of such a black pigment is suitably 10 to 100 parts by mass per 100 parts by mass of the glass fine particles.

  Moreover, what was previously made into a slurry can be used for a black pigment. In this case, the organic solvent used for the slurry can be arbitrarily selected, but it is desirable to use the same type of solvent as that used in the paste in order to prevent solvent shock. The pigment concentration in the slurry can be arbitrarily selected, but is preferably 50 to 80% in consideration of workability and the like.

  Examples of the conductive powder include metal powders such as silver (Ag), gold (Au), nickel (Ni), copper (Cu), aluminum (Al), tin (Sn), platinum (Pt), and ruthenium (Ru). In addition to simple substances and alloys thereof, tin oxide (SnO 2), indium oxide (In 2 O 3), ITO (Indium Tin Oxide), ruthenium oxide (RuO 2), and the like can be used. These can be used alone or as a mixed powder of two or more.

  Various shapes such as a spherical shape, a flake shape, and a dentlite shape can be used as the conductive powder, but it is preferable to use a spherical shape in consideration of optical characteristics and dispersibility. The average particle diameter is preferably 10 μm or less, more preferably 5 μm or less from the viewpoint of the line shape. In addition, in order to prevent oxidation of the conductive powder, to improve dispersibility in the paste, and to stabilize developability, it is particularly preferable to treat Ag, Ni, and Al with a fatty acid. Examples of fatty acids include oleic acid, linoleic acid, linolenic acid, and stearic acid.

  The proportion of the conductive powder is appropriately 50 to 2000 parts by mass when the total amount of paste components other than the conductive powder is 100 parts by mass. When the blending amount of the conductive powder is less than 50 parts by mass, the conductor circuit line width shrinkage or disconnection tends to occur. On the other hand, when the blending amount exceeds 2000 parts by mass, the light transmission is impaired, and the composition is sufficient. It is difficult to obtain a good photocurability. Furthermore, in order to improve the strength of the film after firing and the adhesion to the substrate, the glass fine particles as described above can be added at a ratio of 1 to 30 parts by mass per 100 parts by mass of the metal powder.

Next, the “organic component containing a photopolymerizable compound” as the component (B) means that the photopolymerizable component is included as an essential component. Examples of the photopolymerizable component include a carboxyl group-containing photosensitive resin (oligomer or polymer), a photopolymerizable monomer, an oligomer, and / or a polymer.
The optional organic components include organic solvents and dispersants useful for pasting the composition, resins that do not have photopolymerizability, photopolymerization initiators other than the component (C), photosensitizers, and stability. Agents, antifoaming / leveling agents, silane coupling agents, antioxidants and the like.

Examples of the photopolymerization component constituting the organic component containing the photopolymerizable compound include a carboxyl group-containing photosensitive resin that itself has an ethylenically unsaturated double bond.
Specifically, examples of resins that can be suitably used (any of oligomers and polymers) include the following.
(1) A carboxyl group-containing photosensitive resin obtained by adding an ethylenically unsaturated group as a pendant to a copolymer of an unsaturated carboxylic acid and a compound having an unsaturated double bond. (2) Epoxy group and unsaturated two Carboxyl group-containing photosensitivity obtained by reacting a copolymer of a compound having a heavy bond and a compound having an unsaturated double bond with an unsaturated carboxylic acid, and reacting the resulting secondary hydroxyl group with a polybasic acid anhydride. (3) carboxyl group-containing photosensitivity obtained by reacting a compound of an acid anhydride having an unsaturated double bond and a compound having an unsaturated double bond with a compound having a hydroxyl group and an unsaturated double bond Resin (4) A carboxyl group-containing photosensitive resin obtained by reacting a polyfunctional epoxy compound with an unsaturated monocarboxylic acid and reacting the resulting secondary hydroxyl group with a polybasic acid anhydride. (5) a hydroxyl group -containing polymer polybasic acid carboxyl group-containing resin obtained by the anhydride is reacted, an epoxy group and an unsaturated double bond carboxyl group-containing photosensitive resin obtained further by reacting a compound having the

Examples of the resin component other than the photopolymerizable component constituting the organic component containing the photopolymerizable compound include a carboxyl group-containing resin having no ethylenically unsaturated double bond.
Specifically, examples of resins that can be suitably used (any of oligomers and polymers) include the following.
(1) A carboxyl group-containing resin obtained by copolymerizing an unsaturated carboxylic acid and a compound having an unsaturated double bond (2) a copolymer of a compound having an unsaturated double bond and glycidyl (meth) acrylate A carboxyl group obtained by reacting an epoxy acid with an organic acid having one carboxyl group in one molecule and no ethylenically unsaturated bond, and reacting a polybasic acid anhydride with the generated secondary hydroxyl group -Containing resin (3) carboxyl group-containing resin obtained by reacting a hydroxyl group-containing polymer with a polybasic acid anhydride

  Such carboxyl group-containing photosensitive resin and carboxyl group-containing resin may be used alone or in combination, but in any case, they are blended in a proportion of 10 to 80% by mass of the total amount of the composition. It is preferable. When the blending amount of these resins is less than the above range, the distribution of the resin in the film to be formed tends to be non-uniform, especially in the case of a carboxyl group-containing photosensitive resin, sufficient photocurability and photocuring depth. Is difficult to obtain, and patterning by selective exposure and development becomes difficult. On the other hand, if it is more than the above range, it is not preferable because the pattern during baking and the shrinkage of the line width are likely to occur.

  The carboxyl group-containing photosensitive resin and the carboxyl group-containing resin have a weight average molecular weight of 1,000 to 100,000, preferably 5,000 to 70,000, and an acid value of 50 to 250 mgKOH / g. In the case of a carboxyl group-containing photosensitive resin, those having a double bond equivalent of 350 to 2,000, preferably 400 to 1,500 can be suitably used. If the weight average molecular weight of the resin is lower than 1,000, the adhesion of the film during development is adversely affected. On the other hand, if it is higher than 100,000, development failure tends to occur, which is not preferable. On the other hand, when the acid value is lower than 50 mgKOH / g, the solubility in an alkaline aqueous solution is insufficient, and development failure tends to occur. Part) is not preferable. Furthermore, in the case of a carboxyl group-containing photosensitive resin, if the double bond equivalent is less than 350, the residue is likely to remain at the time of baking, whereas if it is greater than 2,000, the work margin during development is narrow, Moreover, since a high exposure amount is required at the time of photocuring, it is not preferable.

A photopolymerizable monomer is mentioned as another photopolymerization component which comprises the organic component containing the said photopolymerizable compound. This photopolymerizable monomer imparts photocurability in the paste (for example, effective when the above carboxyl group-containing resin having no ethylenically unsaturated double bond is used), promoting the photocurability of the paste. And used to improve developability.
Examples of the photopolymerizable monomer include 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, polyethylene glycol diacrylate, polyurethane diacrylate, trimethylolpropane triacrylate, and pentaerythritol triacrylate. Acrylate, pentaerythritol tetraacrylate, trimethylolpropane ethylene oxide modified triacrylate, trimethylolpropane propylene oxide modified triacrylate, dipentaerythritol pentaacrylate, dipentaerythritol hexaacrylate and each methacrylate corresponding to the above acrylate; phthalic acid, adipine Acid, maleic acid, itacone Mono-, di-, tri- or higher polyesters of polybasic acids such as succinic acid, trimellitic acid, terephthalic acid and the like and hydroxyalkyl (meth) acrylates, but are limited to specific ones. It is not a thing, and these can be used individually or in combination of 2 or more types. Among these photopolymerizable monomers, polyfunctional monomers having two or more acryloyl groups or methacryloyl groups in one molecule are preferable.

  The blending amount of such a photopolymerizable monomer is suitably 20 to 100 parts by mass per 100 parts by mass of the resin (carboxyl group-containing photosensitive resin and / or carboxyl group-containing resin). When the blending amount of the photopolymerizable monomer is less than the above range, it is difficult to obtain sufficient photocurability of the composition. On the other hand, when the amount exceeds the above range, the light on the surface portion is larger than the deep portion of the film. Since curing becomes faster, uneven curing tends to occur.

  Specific examples of the photopolymerization initiator other than the component (C) constituting the organic component containing the photopolymerizable compound include benzoin and benzoin alkyl ethers such as benzoin, benzoin methyl ether, benzoin ethyl ether, and benzoin isopropyl ether; Acetophenones such as acetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 1,1-dichloroacetophenone; 2-methyl-1- [4- (methylthio) phenyl] -2- Aminoacetophenones such as morpholinopropan-1-one and 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1; 2-methylanthraquinone, 2-ethylanthraquinone, 2-t- Butyl anthraquinone, Anthraquinones such as chloroanthraquinone; thioxanthones such as 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2-chlorothioxanthone and 2,4-diisopropylthioxanthone; ketals such as acetophenone dimethyl ketal and benzyldimethyl ketal; Benzophenones such as benzophenone; or xanthones; (2,6-dimethoxybenzoyl) -2,4,4-pentylphosphine oxide, bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide, 2,4, Phosphine oxides such as 6-trimethylbenzoyldiphenylphosphine oxide and ethyl-2,4,6-trimethylbenzoylphenyl phosphinate; various peroxides; It can be used alone or in combination of two or more these conventionally known photopolymerization initiator. The blending ratio of these photopolymerization initiators can be blended to such an extent that the effect of the photopolymerization initiator of component (C) is not impaired.

  In addition, the above photopolymerization initiator includes three kinds such as N, N-dimethylaminobenzoic acid ethyl ester, N, N-dimethylaminobenzoic acid isoamyl ester, pentyl-4-dimethylaminobenzoate, triethylamine, and triethanolamine. It can be used in combination with one or more of photosensitizers such as secondary amines.

When the photosensitive paste of the present invention is blended with an inorganic filler or glass fine particles, the storage stability of the resulting paste is poor, and the coating workability tends to be deteriorated due to gelation or decrease in fluidity.
Therefore, in the photosensitive paste of the present invention, in order to improve the storage stability of the paste, a compound having an effect such as complexation or salt formation with a metal or oxide powder which is a component of an inorganic filler or glass fine particles is stabilized. It is preferable to add as an agent.
As this stabilizer, malonic acid, adipic acid, formic acid, acetic acid, acetoacetic acid, citric acid, stearic acid, maleic acid, fumaric acid, phthalic acid and other organic acids, phosphoric acid, phosphorous acid, hypophosphorous acid Various phosphoric acid compounds such as methyl phosphate, ethyl phosphate, butyl phosphate, phenyl phosphate, ethyl phosphite, diphenyl phosphite, mono (2-methacryloyloxyethyl) acid phosphate (inorganic phosphoric acid, organic phosphorus Acid) and the like, and may be used alone or in combination of two or more.
Such a stabilizer is preferably added at a ratio of 0.1 to 10 parts by mass per 100 parts by mass of the glass fine particles or inorganic filler.

Moreover, when the photosensitive paste of this invention mix | blends a photopolymerizable monomer, the storage stability of the obtained paste is bad, and there exists a tendency for coating workability | operativity to worsen by gelatinization or a fluid fall.
Therefore, in the photosensitive paste of the present invention, it is preferable to add a thermal polymerization inhibitor of a photopolymerizable monomer in order to improve the storage stability of the paste.
Examples of the thermal polymerization inhibitor include phenothiazine, 2-ethylanthraquinone, hydroquinone, N-phenylnaphthylamine, chloranil, pyrogallol, benzoquinone, t-butylcatechol, and the like, which can be used alone or in combination of two or more. .
Such a thermal polymerization inhibitor is preferably added at a ratio of 0.01 to 1 part by mass per 100 parts by mass of the resin component.

The photosensitive paste of the present invention is made into a paste by diluting the composition, and can be easily applied, and an appropriate amount of an organic solvent is blended to form a film by drying and enable contact exposure. be able to.
Specifically, ketones such as methyl ethyl ketone and cyclohexanone; aromatic hydrocarbons such as toluene, xylene and tetramethylbenzene; cellosolve, methyl cellosolve, carbitol, methyl carbitol, butyl carbitol, propylene glycol monomethyl ether, di Glycol ethers such as propylene glycol monomethyl ether, dipropylene glycol monoethyl ether, triethylene glycol monoethyl ether; ethyl acetate, butyl acetate, cellosolve acetate, butyl cellosolve acetate, carbitol acetate, butyl carbitol acetate, propylene glycol monomethyl ether acetate Acetic acid esters such as ethanol, propanol, ethylene glycol, propylene glycol And alcohols such as terpineol; aliphatic hydrocarbons such as octane and decane; petroleum solvents such as petroleum ether, petroleum naphtha, hydrogenated petroleum naphtha, and solvent naphtha. These may be used alone or in combination of two or more. Can be used.

  If necessary, the photosensitive paste of the present invention may further contain other additives such as a defoaming / leveling agent such as silicone and acrylic, and a silane coupling agent for improving the adhesion of the film. You can also. Furthermore, if necessary, fine particles such as metal oxides, silicon oxides, boron oxides, and the like, which are known and commonly used antioxidants, and as binding components to the substrate during firing may be added.

  The photosensitive paste of the present invention as described above may be laminated on a substrate when it is previously formed into a film, but in the case of a paste, a screen printing method, a bar coater, a blade coater For example, about 60 to 120 ° C. in a hot-air circulating drying furnace or a far-infrared drying furnace in order to apply to a substrate, for example, a glass substrate serving as a front substrate of a PDP by a suitable coating method. The organic solvent is evaporated by drying for about 5 to 40 minutes to obtain a tack-free coating film. Thereafter, selective exposure, development, and baking are performed to form an electrode circuit having a predetermined fired product pattern.

As the exposure step, contact exposure and non-contact exposure using a negative mask having a predetermined exposure pattern are possible. As the exposure light source, a halogen lamp, a high-pressure mercury lamp, a laser beam, a metal halide lamp, a black lamp, an electrodeless lamp, or the like is used. The exposure amount is preferably about 50 to 1000 mJ / cm ² .

  As the development step, a spray method, an immersion method, or the like is used. Developers include aqueous alkali metal solutions such as sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate and sodium silicate, and aqueous amine solutions such as monoethanolamine, diethanolamine and triethanolamine, especially about 1.5% by mass or less. A dilute alkaline aqueous solution having a concentration of 1 is preferably used, as long as the carboxyl group of the carboxyl group-containing resin in the composition is saponified and the uncured part (unexposed part) is removed. It is not limited to. Further, it is preferable to perform washing with water and acid neutralization in order to remove unnecessary developer after development.

  In the baking step, the substrate after development is subjected to heat treatment at about 400 to 600 ° C. in air or in a nitrogen atmosphere to form a desired fired product pattern. In addition, it is preferable to set the temperature increase rate at this time to 20 degrees C / min or less.

  In addition, an inorganic fine particle (A) component can be suitably selected according to the kind of desired baked material pattern. For example, in the case of forming an electrode pattern, a conductive powder is used, but it is preferable to use an appropriate amount of glass fine particles in combination in order to improve the firing property. In particular, when forming a black electrode pattern, a black pigment is also used. In the case of a black matrix pattern, glass fine particles and black pigment are used, and glass fine particles are used to form the partition pattern.

  EXAMPLES Hereinafter, the present invention will be described in detail with reference to examples and comparative examples, but the present invention is not limited to the following examples. “Parts” and “%” are based on mass unless otherwise specified.

(Synthesis Example 1)
A flask equipped with a thermometer, stirrer, dropping funnel and reflux condenser is charged with methyl methacrylate and methacrylic acid in a molar ratio of 0.76: 0.24, dipropylene glycol monomethyl ether as a solvent, and azobisiso as a catalyst. Butyronitrile was added and stirred at 80 ° C. for 2 to 6 hours under a nitrogen atmosphere to obtain a resin solution. The resin solution was cooled, methylhydroquinone as a polymerization inhibitor, tetrabutylphosphonium bromide as a catalyst, and glycidyl methacrylate was added at 0.12 to 1 mol of the carboxyl group of the resin under the conditions of 95 to 105 ° C. for 16 hours. Addition reaction was carried out at an addition molar ratio of a molar ratio, and the reaction product was taken out after cooling to produce a carboxyl group-containing photosensitive resin A. This resin A had a weight average molecular weight of about 10,000, an acid value of 59 mgKOH / g, and a double bond equivalent of 950. In addition, the measurement of the weight average molecular weight of the obtained copolymer resin is Shimadzu Corporation pump LC-6AD, Showa Denko Co., Ltd. column Shodex (trademark) KF-804, KF-803, KF-802. Was measured by high performance liquid chromatography.

(Synthesis Example 2)
Carboxyl group-containing resin B was produced in the same manner as in Synthesis Example 1 except that the charge ratio of methyl methacrylate and methacrylic acid was 0.87: 0.13 in terms of molar ratio and glycidyl methacrylate was not subjected to addition reaction. This resin B had a weight average molecular weight of about 10,000 and an acid value of 74 mgKOH / g.

The resin A or B thus obtained was used and blended at the composition ratio shown below, stirred with a stirrer, and then kneaded with a three-roll mill to form a paste. Kneaded meat conditions are 1 kg of sample amount at room temperature for 30 minutes.
As the glass _{powder, PbO 60%, B 2 0} 3 20%, SiO 2 15%, Al 2 0 3 5% and milled, the thermal expansion coefficient ^{_{α 300 = 70 × 10 -7 /}} ℃, the glass transition point What set it as 445 degreeC and the average particle diameter of 1.6 micrometers was used.

(Composition Example 1)
Resin A 100.0 parts Pentaerythritol triacrylate 50.0 parts 2-Dimethylamino-2- (4-methylbenzyl)
-1- (4-morpholinophenyl) butanone (Irgacure 379, manufactured by Ciba Specialty Chemicals)
10.0 parts Tripropylene glycol monomethyl ether 80.0 parts Silver powder 600.0 parts Glass powder 30.0 parts Phosphate ester 1.0 part

(Composition Example 2)
Resin A 100.0 parts Pentaerythritol triacrylate 50.0 parts 2-Dimethylamino-2- (4-methylbenzyl)
-1- (4-morpholinophenyl) butanone (Irgacure 379, manufactured by Ciba Specialty Chemicals)
5.0 parts Tripropylene glycol monomethyl ether 80.0 parts Silver powder 600.0 parts Glass powder 30.0 parts Phosphate ester 1.0 part

(Composition Example 3)
Resin B 100.0 parts Pentaerythritol triacrylate 50.0 parts 2-Dimethylamino-2- (4-methylbenzyl)
-1- (4-morpholinophenyl) butanone (Irgacure 379, manufactured by Ciba Specialty Chemicals)
10.0 parts Tripropylene glycol monomethyl ether 40.0 parts Cobalt tetroxide (Co ₃ O ₄ ) 50.0 parts

(Composition Example 4)
Resin B 100.0 parts Pentaerythritol triacrylate 50.0 parts 2-Dimethylamino-2- (4-methylbenzyl)
-1- (4-morpholinophenyl) butanone (Irgacure 379, manufactured by Ciba Specialty Chemicals)
5.0 parts tripropylene glycol monomethyl ether 40.0 parts cobalt trioxide (Co ₃ O ₄ ) 50.0 parts

(Comparative composition examples 1 to 4)
Instead of 2-dimethylamino-2- (4-methylbenzyl) -1- (4-morpholinophenyl) butanone as the photopolymerization initiator, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) ) -Butanone (Irgacure 369, manufactured by Ciba Specialty Chemicals) was used to obtain pastes in the same manner as in Composition Examples 1 to 4, respectively.

For each of the pastes of Composition Examples 1 to 4 and Comparative Composition Examples 1 to 4 thus obtained, the maximum particle size after kneading and the maximum particle size after refrigerated storage were measured, and light during low temperature storage The crystallization of the polymerization initiator was evaluated. Further, the resolution, the line shape after development, and the line shape after baking were evaluated.
The evaluation method is as follows.

Maximum particle size after boiled meat and maximum particle size after refrigerated storage:
1 kg of the evaluation composition was kneaded for 30 minutes using a ceramic three roll to prepare an evaluation paste. With respect to this evaluation paste, the maximum particle size after the batter was immediately after the batter, and the maximum particle size after the refrigerated storage was stored at 4 ° C. for 1 week and left at 25 ° C. for 3 hours, and then the maximum particle size was obtained using a grind gauge. The particle size was measured, and the state of crystallization was evaluated by the change in the maximum particle size.

Resolution and line shape:
(Evaluation Substrate) The substrate used for this evaluation was coated on the entire surface of an ITO film-coated glass substrate using a 300-mesh polyester screen, and then heated at 90 ° C. in a hot air circulating drying oven. The film was dried for 5 minutes to form a film having good dryness to the touch. Thereafter, the light source was a metal halide lamp, and exposure was performed using a striped negative mask having a line width of 10 to 100 μm and a space width of 100 μm so that the integrated light amount on the composition was 300 mJ / cm ² . Development was performed for 20 seconds using a 0.5 wt% aqueous solution of Na ₂ CO ₃ and washed with water. Finally, the temperature was raised at 5 ° C./min in an air atmosphere and baked at 580 ° C. for 30 minutes to produce a substrate.
(Evaluation method) The resolution was evaluated by investigating the thinnest line that can form a pattern within a line width of 10 to 100 μm.
The line shape after development was evaluated by observing the pattern that had been completed up to development with a microscope and checking for irregularities in the line and whether there was any distortion.
About the line shape after baking, the pattern which complete | finished to baking was observed with the microscope, and it evaluated by whether there was no irregular variation in a line, and there was no twist. The evaluation criteria for the line shape are as follows.
○: There is no irregular variation and there is no twist.
(Triangle | delta): There are some irregular variations, a twist, etc.
X: Irregular variation, warping, etc.

  These evaluation results are shown in Table 1. As is clear from the results shown in Table 1, the paste according to the composition of the present invention is less susceptible to crystallization of the photopolymerization initiator and has a high definition even after storage at a lower temperature than the paste of the comparative composition. It was found that a pattern could be formed.

It is a partial exploded perspective view of a surface discharge type AC type PDP.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Front glass substrate 2a, 2b Display electrode 3, 3a, 3b Transparent electrode 4, 4a, 4b Bus electrode 5 Transparent dielectric layer 6 Protective layer 10 Black matrix 11 Back glass substrate 12 Rib 13 Address electrode 14a, 14b, 14c Phosphor film

Claims (7)

(A) inorganic fine particles, (B) an organic component containing a photopolymerizable compound, and (C) 2-dimethylamino-2- (4-methylbenzyl) -1- (4-morpholinophenyl) as a photopolymerization initiator A photosensitive paste containing butanone. The photosensitive paste according to claim 1, wherein the inorganic fine particles (A) are at least one selected from glass fine particles, inorganic fillers, black pigments, and conductive powders. The photosensitive paste according to claim 2, wherein the glass fine particles have a glass transition point (Tg) of 300 to 500 ° C and a glass softening point (Ts) of 400 to 600 ° C. The photosensitive conductive paste according to claim 2, wherein the conductive powder is at least one metal powder selected from Ag, Au, Pd, Ni, Cu, Al, and Pt. The organic component (B) containing the said photopolymerizable compound contains the photosensitive monomer and oligomer which have at least 1 acryloyl group and / or methacryloyl group in 1 molecule. Photosensitive paste. The organic component (B) containing the photopolymerizable compound contains an oligomer or polymer having a carboxyl group and a weight average molecular weight of 1,000 to 100,000 and an acid value of 20 to 150 mgKOH / g. The alkali development type photosensitive paste as described in any one of Claims. At least one kind of baking chosen from the partition pattern of a flat panel display, a dielectric material pattern, an electrode pattern, and a black matrix pattern formed using the photosensitive paste as described in any one of Claims 1 thru | or 6. A plasma display panel with an object pattern.

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