KR20080023649A - Photosensitive Paste and Plasma Display Panel - Google Patents

Abstract

The present invention is a photosensitive paste used for forming a high precision microelectrode of a plasma display panel that can be printed without pinholes or printing irregularities, and has excellent adhesion to a substrate, resolution, and the like in each process of drying, exposure, development, and baking. Provided is a photosensitive paste capable of forming a fired film without impairing plasticity. In addition, the present invention provides a plasma display panel in which a high-precision fine fired material pattern is formed of the photosensitive paste.

The photosensitive paste of this invention is a photosensitive paste containing (A) organic binder, (B) photopolymerizable monomer, (C) photoinitiator, (D) inorganic fine particle, (E) organic solvent, and (F) additive, A high boiling point organic solvent having a boiling point of 210 ° C. or higher is contained in the organic solvent (E), and one or two or more types of dispersants selected from amine-based, phosphorus-based and carboxylic acid-based dispersants together with an acrylic leveling agent as an additive (F). do.

Description

Photosensitive paste and plasma display panel

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photosensitive paste useful for forming partition patterns, dielectric patterns, electrode patterns, and black matrix patterns of plasma display panels (hereinafter, abbreviated as PDPs). More specifically, it can be preferably used to form the fired material pattern for PDP having stable printability, and excellent adhesion to the substrate, resolution, plasticity in each process of drying, exposure, development, firing It is related with the photosensitive paste which can form a baking film, without damaging.

PDPs are flat displays which display images and information using light emission by plasma discharge, and are classified into DC type and AC type according to the panel structure and driving method. The principle of color display by the PDP is to generate a plasma discharge in a cell space (discharge space) between opposite electrodes formed on the front glass substrate and the rear glass substrate spaced by ribs, and to enclose in each cell space. The phosphor formed on the inner surface of the back glass substrate is excited by ultraviolet rays generated by the discharge of gases such as He and Xe to generate visible light of three primary colors. Each cell space is partitioned by lattice ribs in the DC-type PDP, while the cell space is partitioned by ribs arranged in parallel with the substrate surface in the AC-type PDP. A brief description will be given below with reference to the accompanying drawings.

Fig. 1 partially shows a structural example of a surface discharge type AC PDP with a three-electrode structure in full color display. On the lower surface of the front glass substrate 1, a pair of display electrodes including transparent electrodes 3a and 3b for discharge and bus electrodes 4a and 4b for lowering the line resistance of the transparent electrode ( 2a) and (2b) are provided in multiple numbers by predetermined pitch. 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. have. The protective layer 6 plays a role of protecting the display electrode, maintaining the discharge state, and the like. On the other hand, on the rear glass substrate 11, a plurality of stripe ribs (partition walls) 12 which partition the discharge space and address electrodes (data electrodes) 13 disposed in each discharge space are arranged in a predetermined pitch. have. In addition, the phosphor film of three colors of red (14a), blue (14b), and green (14c) is regularly arranged on the inner surface of each discharge space. In full-color display, as described above, three colors of red, blue, and green are used. One pixel of the fluorescent film 14a, 14b, 14c of primary color is comprised.

Further, in order to further increase the contrast of the image, stripe-like black patterns 10 and 10 are formed on both side portions of the pair of display electrodes 2a and 2b forming the discharge space.

In the PDP having the above structure, an alternating pulse voltage is applied between the pair of display electrodes 2a and 2b to discharge between the electrodes on the same substrate, which is called " surface discharge method ".

Further, in the PDP having the above structure, ultraviolet rays generated by the discharge excite the phosphor films 14a, 14b, and 14c of the back substrate 11, and the generated visible light is transferred to the transparent electrode of the front substrate 1 ( 3a) and 3b are made to pass through.

In the PDP having such a structure, the bus electrodes 4a, 4b and address electrodes 2a, 2b are formed by depositing or sputtering three layers of Cr-Cu-Cr in the prior art. Patterning was performed by lithography.

However, since the number of steps is large and the cost is high, in recent years, a method of baking a conductive paste such as silver paste and then baking it, or for forming a line width of 150 μm or less, is applied to a photosensitive conductive paste and exposed through a pattern mask. After the development, the method is then fired.

In this way, in the substrate of the PDP in which the electrode is formed, multifaceted fabrication of several substrates is performed from one large substrate for large screen size and cost reduction. However, when paste is applied to a substrate by screen printing, there is a problem that pinholes and printing irregularities are likely to occur.

Accordingly, the present invention has been made to solve the problems of the prior art, the main object of which is a photosensitive paste used to form a high-precision fine electrode pattern of the plasma display panel, which can be printed without pinholes or printing irregularities, It is providing the photosensitive paste which can form a baking film, without impairing the outstanding adhesiveness, resolution, and plasticity with respect to a board | substrate in each process of drying, exposure, image development, and baking.

Another object of the present invention is to provide a plasma display panel in which a high-precision fine baked material pattern is formed of such a photosensitive paste.

According to the first aspect of the present invention for achieving the above object, (A) an organic binder, (B) a photopolymerizable monomer, (C) a photoinitiator, (D) inorganic fine particles, (E) an organic solvent, and (F ) A photosensitive paste containing an additive, which contains a high boiling point organic solvent having a boiling point of 210 ° C. or higher in the organic solvent (E), and is selected from an amine-based, phosphorus-based and carboxylic acid-based dispersant with an acrylic leveling agent as the additive (F). There is provided a photosensitive paste containing one or two or more dispersants.

In one aspect of the present invention, diethylene glycol monoethyl ether acetate is contained as the high boiling point organic solvent having a boiling point of 210 ° C. or higher in the organic solvent (E), and its content is 5% by mass or more with respect to the total amount of the photosensitive paste.

According to another aspect of the present invention, there is provided a plasma display panel having an electrode formed of a fired product of the photosensitive paste.

By forming the coating film with few pinholes using the photosensitive paste of this invention, since the panel which does not have an electrode defect and a shape defect can be manufactured stably, it is very useful for mass productivity of PDP and cost reduction.

MEANS TO SOLVE THE PROBLEM The present inventors earnestly researched for the said objective, As a result, (A) organic binder, (B) photopolymerizable monomer, (C) photoinitiator, (D) inorganic fine particle, (E) organic solvent, and (F) ) A photosensitive paste containing an additive, which contains a high boiling point organic solvent having a boiling point of 210 ° C. or higher in the organic solvent (E), and is selected from an amine-based, phosphorus-based and carboxylic acid-based dispersant with an acrylic leveling agent as the additive (F). The photosensitive paste containing one type or two or more types of dispersants finds that the coating film after glass substrate printing is uniform, pinholes are reduced, and as a result, it is possible to stably produce a panel free of electrode defects and shape defects. It is time to complete.

As the organic binder (A) used in the photosensitive paste of the present invention, both a resin having a carboxyl group, specifically, a carboxyl group-containing photosensitive resin having an ethylenically unsaturated double bond and a carboxyl group-containing resin not having an ethylenically unsaturated double bond Can be used Specifically, the following are mentioned.

(1) carboxyl group-containing resin obtained by copolymerizing unsaturated carboxylic acids, such as (meth) acrylic acid, and compounds which have unsaturated double bonds, such as methyl (meth) acrylate,

 (2) Ethylene by glycidyl (meth) acrylate, (meth) acrylic acid chloride, etc. in a copolymer of unsaturated carboxylic acids such as (meth) acrylic acid and unsaturated double bonds such as methyl (meth) acrylate Carboxyl group-containing photosensitive resin obtained by adding a unsaturated unsaturated group as a pendant,

(3) unsaturated carboxyl such as (meth) acrylic acid in a copolymer of a compound having an unsaturated double bond such as methyl (meth) acrylate with an epoxy group such as glycidyl (meth) acrylate; Carboxyl group-containing photosensitive resin obtained by making an acid react and making polybasic acid anhydrides, such as tetrahydrophthalic anhydride, react with the produced | generated secondary hydroxyl group,

(4) In the copolymer of an acid anhydride having an unsaturated double bond such as maleic anhydride and a compound having an unsaturated double bond such as styrene, a hydroxyl group such as 2-hydroxyethyl (meth) acrylate has an unsaturated double bond Carboxyl group-containing photosensitive resin obtained by making a compound react,

(5) a carboxyl group-containing photosensitive resin obtained by reacting a polyfunctional epoxy compound with unsaturated monocarboxylic acids such as (meth) acrylic acid and reacting the resulting secondary hydroxyl group with a polybasic acid anhydride such as tetrahydrophthalic anhydride;

(6) An organic acid having one carboxyl group in one molecule and having no ethylenically unsaturated bond in the epoxy group of the copolymer of a compound having an unsaturated double bond such as methyl (meth) acrylate and glycidyl (meth) acrylate. Carboxyl group-containing resin obtained by reacting and reacting a polybasic acid anhydride with the produced | generated secondary hydroxyl group,

(7) carboxyl group-containing resin obtained by making polybasic acid anhydride react with hydroxyl-containing polymers, such as polyvinyl alcohol, and

(8) A compound having an unsaturated double bond such as glycidyl (meth) acrylate is added to a carboxyl group-containing resin obtained by reacting a polybasic acid anhydride such as tetrahydrophthalic anhydride with a hydroxyl group-containing polymer such as polyvinyl alcohol. Carboxyl group-containing photosensitive resin etc. which are obtained by making it react, and especially resin of (1), (2), (3), (6) are used preferably.

In addition, in this specification, a (meth) acrylate is a term used generically for acrylate, methacrylate, and mixtures thereof, and the same also about other similar expressions.

Although this carboxyl group-containing resin and carboxyl group-containing photosensitive resin can be used individually or in mixture, in any case, it is preferable to mix these in the ratio of 10-80 mass% of the total mass of a composition in total. When the compounding quantity of these polymers is too small than the said range, distribution of the said resin in the film to form easily becomes easy, sufficient photocurability and photocuring depth are hard to be obtained, and patterning by selective exposure and image development becomes difficult. On the other hand, when it exceeds too much, it is unpreferable since distortion of a pattern at the time of baking and line shrinkage easily occur.

Moreover, as said carboxyl group-containing resin and carboxyl group-containing photosensitive resin, the weight average molecular weights 1,000-100,000, More preferably, 5,000-70,000, and acid value 50-250 mgKOH / g, In the case of the carboxyl group-containing photosensitive resin, the double bond equivalent weight It is preferably 350 to 2,000, more preferably 400 to 1,500. When the molecular weight of the said resin is lower than 1,000, it adversely affects the adhesiveness of the film at the time of image development, and when it is higher than 100,000, it is unpreferable because developing defects are easy to occur. In addition, when the acid value is lower than 50 mgKOH / g, the solubility in an aqueous alkali solution is insufficient, and development defects are likely to occur. On the other hand, when the acid value is higher than 250 mgKOH / g, deterioration of the adhesion of the film at the time of development or a photocuring part (furnace) It is not preferable because dissolution of the miner) occurs. In addition, in the case of the carboxyl group-containing photosensitive resin, when the double bond equivalent of the photosensitive resin is less than 350, the residue is likely to remain at the time of firing, while if it is larger than 2,000, the work margin at development is narrow and a high exposure amount at the time of photocuring is obtained. It is not preferable because it is necessary.

The photopolymerizable monomer (B) used for the photosensitive paste of this invention is used in order to promote the photocurability of a composition, and to improve developability. For example, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, polyethylene glycol diacrylate, polyurethane diacrylate, trimethylol propane tree Acrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, trimethylolpropane ethylene oxide modified triacrylate, trimethylolpropanepropylene oxide modified triacrylate, dipentaerythritol pentaacrylate, dipentaerythrate Lithol hexaacrylate and each methacrylate corresponding to the said acrylate; Mono-, di-, tri- or more polyesters of polybasic acids such as phthalic acid, adipic acid, maleic acid, itaconic acid, succinic acid, trimellitic acid and terephthalic acid with hydroxyalkyl (meth) acrylates It does not specifically limit, These can be used individually or in combination of 2 or more types. Among these photopolymerizable monomers, the polyfunctional monomer which has a 2 or more acryloyl group or a methacryloyl group in 1 molecule is preferable.

As for the compounding ratio of such a photopolymerizable monomer (B), 20-100 mass parts is preferable per 100 mass parts of said organic binders (carboxyl group-containing photosensitive resin and / or carboxyl group-containing resin) (A). When the compounding quantity of a photopolymerizable monomer (B) is less than the said range, sufficient photocurability of a composition is hard to be acquired, and when it exceeds the said range, when it becomes a large quantity, photocuring of the surface part will become quick compared with the core part of a film, and it hardens | cures Nonuniformity is likely to occur.

Specific examples of the photopolymerization initiator (C) used in the photosensitive paste of the present invention 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, and 1,1-dichloroacetophenone; 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropane-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone- Aminoacetophenones such as 1,2- (dimethylamino) -2-[(4-methylphenyl) methyl] -1- [4- (4-morpholinyl) phenyl] -1-butanone; Anthraquinones such as 2-methylanthraquinone, 2-ethylanthraquinone, 2-t-butylanthraquinone and 1-chloroanthraquinone; Thioxanthones such as 2,4-dimethyl thioxanthone, 2,4-diethyl thioxanthone, 2-chlorothioxanthone, and 2,4-diisopropyl thioxanthone; Ketals such as acetophenone dimethyl ketal and benzyl dimethyl ketal; Benzophenones such as benzophenone; Or xanthones; (2,6-dimethoxybenzoyl) -2,4,4-pentylphosphineoxide, bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide, 2,4,6-trimethylbenzoyldiphenylphosphine jade Phosphine oxides such as seeds and ethyl-2,4,6-trimethylbenzoylphenylphosphinate; Various peroxides etc. are mentioned, These known conventional photoinitiators can be used individually or in combination of 2 or more types.

As for the compounding ratio of these photoinitiators (C), 1-30 mass parts is preferable per 100 mass parts of said organic binders (carboxyl group-containing photosensitive resin and / or carboxyl group-containing resin) (A), More preferably, it is 5-20 mass It is wealth.

Moreover, as above-mentioned photoinitiator (C), N, N- dimethylamino benzoic acid ethyl ester, N, N- dimethylamino benzoic acid isoamyl ester, pentyl-4- dimethylamino benzoate, triethylamine, triethanol It can be used in combination with 1 type, or 2 or more types of photosensitizers, such as tertiary amines, such as an amine.

In addition, when a deeper photocuring depth is required, titanocene-based photopolymerization initiators such as Ciba-Specialty Chemicals, Irgacure-784, etc., which initiate radical polymerization in the visible region as necessary, may be used as curing aids. It can be used in combination.

Moreover, when deeper photocuring depth is calculated | required, a thermal polymerization catalyst can be used together with the said photoinitiator (C) as needed. This thermal polymerization catalyst is capable of reacting the uncured photopolymerizable monomer by aging at a high temperature for several minutes to about 1 hour, and specifically, azo such as peroxides such as benzoyl peroxide and azoisobutyronitrile. Compounds and the like, and preferably 2,2'-azobisisobutyronitrile, 2,2'-azobis-2-methylbutyronitrile, 2,2'-azobis-2,4-divalero Nitrile, 1'-azobis-1-cyclohexanecarbonitrile, dimethyl-2,2'-azobisisobutyrate, 4,4'-azobis-4-cyanovaleric acid, 2-methyl-2,2 '-Azobispropanenitrile, 2,4-dimethyl-2,2,2', 2'-azobispentanenitrile, 1,1'-azobis (1-acetoxy-1-phenylethane), 2,2 , 2 ', 2'-azobis (2-methylbutanamide oxime) dihydrochloride, and the like, and more preferably 1,1'-azobis in a non-environmental, non-halogen form. Acetoxy-1-phenylethane) Can be mentioned.

The photosensitive paste of the present invention contains the inorganic fine particles (D), and preferably contains one or two or more of the glass fine particles, the pigment, the conductive metal powder or the metal oxide, and the inorganic filler as the inorganic fine particles (D). .

The content of the inorganic component is different depending on the desired fired material pattern. First, glass fine particles are used in the case of formation of a partition pattern and a dielectric pattern, and glass fine particles and a black pigment are used in the case of a black matrix pattern. On the other hand, in the case of electrode pattern formation, although conductive powder (conductive metal powder or / and metal oxide) is used, in order to improve plasticity as mentioned later, it is preferable to use an appropriate amount of glass fine particles together, and a black electrode pattern is used. In the case of forming, a black pigment is further used. In addition, aggregate (inorganic filler) can be added to the photosensitive paste composition according to the purpose.

As glass microparticles | fine-particles, what has a glass transition point (Tg) 300-500 degreeC and glass softening point (Ts) 400-600 degreeC, for example, what has a lead oxide, bismuth oxide, or zinc oxide as a main component can be used preferably. In terms of resolution, glass particles having an average particle diameter of 10 m or less, preferably 3 m or less are used.

The black pigment in the inorganic fine particles (D) is used when black is required for the fired product pattern, and includes a black pigment containing one or two or more metal oxides such as Fe, Co, Ni, Cu, Mn, and Al. Can be added.

As the conductive metal powder or the metal oxide in the inorganic fine particles (D), any conductive powder having a specific resistance of 1 × 10 ³ Ω · cm or less can be widely used. Silver (Ag), gold (Au), nickel (Ni), copper (Cu), aluminum (Al), tin (Sn), lead (Pb), zinc (Zn), iron (Fe), platinum (Pt), iridium (Ir), osmium (Os), palladium (Pd), rhodium (Rh), ruthenium (Ru), tungsten (W), molybdenum (Mo) and the like, as well as alloys thereof, tin oxide (SnO ₂ ), indium oxide (In ₂ O ₃ ), and ITO (indium tin oxide (Indium) Tin Oxide)), ruthenium oxide (RuO ₂ ), and the like. These may be used alone or as mixed powders of two or more thereof.

Although the thing of spherical shape, a flake shape, a dendritic shape, etc. can be used for the shape of the said electroconductive metal powder or a metal oxide, it is preferable to use a spherical thing in consideration of optical characteristics and dispersibility. In addition, as an average particle diameter, the thing of 10 micrometers or less in terms of the resolution, Preferably the thing of 5 micrometers or less is used. In addition, in order to prevent oxidation of the conductive metal powder, to improve dispersibility in the composition, and to stabilize developability, it is preferable to perform treatment with fatty acids, particularly for Ag, Ni, and Al. Examples of the fatty acid include oleic acid, linoleic acid, linolenic acid, stearic acid, and the like.

As a compounding ratio of the compounding quantity of such electroconductive metal powder or a metal oxide, 50-80 mass% is preferable with respect to the said photosensitive paste whole quantity. When the compounding quantity of electroconductive powder is less than the said range, since sufficient electroconductivity of the conductor pattern obtained from such a paste is not obtained, and a large amount exceeds the said range, since adhesiveness with a base material will deteriorate, it is unpreferable.

As the inorganic filler in the inorganic fine particles (D), any that can contribute to the improvement of the denseness inside the fired material pattern such as the partition wall such as alumina, silica, zircon, titanium oxide, or the like can be used. That is, although a glass component shrinks at the time of baking, a shrinkage rate and internal density can be adjusted according to the compounding quantity of an inorganic filler.

As an organic solvent (E) used for the photosensitive paste of this invention, it is preferable to use especially the high boiling point organic solvent whose boiling point is 210 degreeC or more, and glycol esters (for example, diethylene glycol monoethyl ether acetate, dipropylene) Glycol monomethyl ether acetate, butyl carbitol acetate, 2,2,4-trimethyl-1,3-pentanediol diisobutylate, and the like); Glycol ethers (for example, ethylene glycol 2-ethylhexyl ether, ethylene glycol phenyl ether, diethylene glycol monobutyl ether, diethylene glycol n-hexyl ether, diethylene glycol 2-ethylhexyl ether, triethylene glycol monomethyl Ether, triethylene glycol monotriethylene glycol monoethyl ether, triethylene glycol monobutyl ether, dipropylene glycol monobutyl ether, dipropylene glycol n-butyl ether, tripropylene glycol monomethyl ether, tripropylene glycol tripropylene glycol n Butyl ether, etc.); Alcohols (for example, diethylene glycol, triethylene glycol, 1,4-butanediol, octanediol, butyl carbitol and the like); Hydrocarbons (for example, brand name Solvesso # 150, Solvesso # 200), etc. are mentioned, These can be used individually or in mixture of 2 or more types. Among these, diethylene glycol monoethyl ether acetate is preferable at the point that the balance of dryness, workability, and printability is favorable. In addition, the upper limit of a boiling point is not specifically limited, It is preferable that it is 300 degrees C or less from a viewpoint of drying. Here, in this invention, a boiling point is a boiling point in 1 atmosphere.

Preferably the compounding ratio of such an organic solvent (E) is 5 mass% or more with respect to paste whole quantity, More preferably, it is 5 mass% or more and 30 mass% or less. When it is less than 5 mass%, it is not preferable because defective plate separation occurs during printing. Moreover, when it contains exceeding 30 mass%, since the viscosity of a paste falls and it becomes difficult to dry the coating film after printing, it is not preferable.

Moreover, an appropriate amount of organic solvent can be mix | blended as solvents other than the high boiling point organic solvent whose boiling point is 210 degreeC or more, such as diethylene glycol monoethyl ether acetate. Specifically, Ketones, such as methyl ethyl ketone and cyclohexanone; Aromatic hydrocarbons such as toluene, xylene and tetramethylbenzene; Glycol ethers such as cellosolve, methyl cellosolve, carbitol, methyl carbitol, propylene glycol monomethyl ether and dipropylene glycol monomethyl ether; Esters such as ethyl acetate, butyl acetate, cellosolve acetate, butyl cellosolve acetate, propylene glycol monomethyl ether acetate, 2,2,4-trimethyl-1,3-pentanediol monoisobutylate, γ-butyrolactone Ryu; Alcohols such as ethanol, propanol, ethylene glycol, propylene glycol and terpineol; Aliphatic hydrocarbons such as octane and decane; Petroleum solvents such as petroleum ether, petroleum naphtha, hydrogenated petroleum naphtha, solvent naphtha, 2,2,4-trimethyl-1,3-pentanediol monoisobutylate, and the like. Can be used in combination.

In the photosensitive paste of this invention, when mix | blending a large amount of inorganic powder with a photocurable resin composition, the storage stability of the composition obtained will deteriorate, and it exists in the tendency for coating workability to deteriorate by gelatinization and fluidity fall. Therefore, in the composition of this invention, in order to improve the storage stability of a composition, the compound which has an effect, such as complexing with metal or oxide powder which is a component of an inorganic powder, or salt formation, can be added as a stabilizer. As a stabilizer, As an inorganic acid, As boric acid, As an organic acid; Formic acid, acetic acid, malic acid, malonic acid, acetoacetic acid, citric acid, stearic acid, maleic acid, fumaric acid, phthalic acid, benzenesulfonic acid, sulfamic acid; In addition, various phosphoric acid compounds such as phosphoric acid, phosphorous acid, hypophosphorous acid, methyl phosphate, ethyl phosphate, butyl phosphate, phenyl phosphate, ethyl phosphite, diphenyl phosphite, and mono (2-methacryloyloxyethyl) phosphate (inorganic phosphoric acid, Acids, such as organic phosphoric acid), and can be used individually or in combination of 2 or more types.

The photosensitive paste of this invention contains 1 type, or 2 or more types of dispersing agent chosen from an amine type, phosphorus type, and carboxylic acid type dispersing agent with an acryl-type leveling agent as an additive (F).

As an acrylic leveling agent (defoamer), specifically methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, tert- butyl acrylate cyclohexyl acrylate Acrylates and the like methacrylates and the like can be used alone or as copolymers obtained by copolymerizing two or more kinds. Examples of commercially available products include Modaflow (Surface Specialties Co., Ltd.), Polyflow Nos. 75, No. 77, No. 85, No. 90, No. 95, and Polyflow S (all Kyocera Co., Ltd.). Kagaku Co., Ltd.), BYK-354, -350, -352, -355, -356 (all are manufactured by BYK Chemie), etc. can be used. Since an acryl-type leveling agent has a suitable compatibility with an acryl-type organic binder, it can prevent defects, such as cratering by the deterioration of the compatibility observed when silicone type is used as a leveling agent.

Examples of commercially available products as dispersants include Disperbyk (registered trademark) -112, -161, -182, and -191 (all manufactured by BYK Chemie) as amine dispersants; As a phosphorus dispersant, light ester P-1M (manufactured by Osaka Yuki Kagaku Kogyo Co., Ltd.), JPA-514 (manufactured by Johoku Kagaku Kogyo Co., Ltd.), Disperbyk-110, -111, -142, -180 (all BYK Chemie Co., Ltd.), DA-325 (manufactured by Kusumoto Kasei Co., Ltd.); As the carboxylic acid-based dispersant, BYK-P105 (manufactured by BYK Chemie), Floren G-700 (manufactured by Kyoeisha Chemical Co., Ltd.), and the like can be used.

In this invention, the preferable compounding ratio of an acryl-type leveling agent and a dispersing agent is 1-10 mass parts, respectively, per 100 mass parts of said organic binders (A). Moreover, as for the compounding ratio of an acrylic leveling agent and a dispersing agent, 1: 10-10: 1 are preferable.

In addition, fine particles such as known conventional antioxidants, thermal polymerization inhibitors for improving thermal stability during storage, and metal oxides, silicon oxides, and boron oxides as bonding components with the substrate during firing may be added as necessary. have.

The photosensitive paste of the present invention preferably has a viscosity at 25 ° C. of 50 to 200 dPa · s, more preferably 80 to 180 dPa · s. If the viscosity is lower than 50 dPa · s, sagging or cratering tends to occur after printing, while if it is higher than 200 dPa · s, workability is lowered, which is not preferable.

The photosensitive paste of the present invention is applied to a substrate, for example, a glass substrate that is a back substrate of a PDP by screen printing, and then, for example, in a hot air circulation drying furnace, a far infrared ray drying furnace, or the like, for example, to obtain a touch-drying property. It dries at 5 degreeC about 5 to 40 minutes, and the organic solvent is evaporated and the coating film without adhesiveness is obtained. Thereafter, selective exposure, development, and baking are performed to form a predetermined pattern.

As an exposure process, contact exposure and non-contact exposure using the negative mask which has a predetermined exposure pattern are possible. As the exposure light source, a halogen lamp, a high pressure mercury lamp, a laser light, a metal halide lamp, an electrodeless lamp and the like are used. As an exposure amount, about 50-1000 mJ / cm <2> is preferable.

As the developing step, a spraying method, a dipping method, or the like is used. As a developing solution, aqueous metal alkali solutions, such as sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, and sodium silicate, aqueous amine solutions, such as monoethanolamine, diethanolamine, and triethanolamine, especially the dilute alkali aqueous solution of the density | concentration of about 1.5 mass% or less is used. Although preferably used, it is preferable that the carboxyl group of the carboxyl group-containing resin in the composition is saponified and the uncured portion (unexposed portion) is removed, and is not limited to the developer as described above. In addition, in order to remove unnecessary developer after development, it is preferable to wash with water or perform acid neutralization.

In the firing step, the substrate after development is subjected to heat treatment at about 500 to 600 ° C. in air or in a nitrogen atmosphere to form a desired pattern.

<Example>

Hereinafter, although this invention is demonstrated concretely based on an Example, this invention is not limited to the following Example. In addition, below, all "parts" are mass parts unless there is particular notice.

As the glass powder was used in a pulverized lead-free glass powder containing _{Bi 2 O 3, B 2 O} 3, ZnO, SiO 2, BaO, average particle size 1.6 ㎛.

After mix | blending with the composition ratio shown in Table 1, stirring with a stirrer, it was ground by the triaxial roll mill and pasteurized. The viscosity (dPa * s) of the obtained paste (Composition Examples 1-3 and Comparative Examples 1-5) was measured, and it was 158, 171, 165, 162, 177, 150, 162, and 151, respectively.

Viscosity Measurement Method

The viscosity at the time of 5 rotations at 25 degreeC was measured using the E-type viscosity meter.

The printing characteristic of the obtained photosensitive paste was investigated by the following evaluation methods. The results are shown in Table 2 below.

The evaluation paste was applied to the entire surface on a glass substrate using a 300 mesh polyester screen. At this time, the separation of the plates was observed. Subsequently, it dried for 15 minutes at 90 degreeC by the far-infrared drying furnace, and formed the film. Next, the dry coating film was observed on the light table, and the printing nonuniformity, the pinhole, and the state of cratering were observed.

The state of plate separation was evaluated by (circle)-x.

○: Good separation of the plate.

(Triangle | delta): Some screens and a coating film stick together at the time of printing, but are separated after printing.

X: Some screens and a coating film adhere at the time of printing, and do not peel even after printing,

The presence or absence of printing nonuniformity was evaluated by (circle)-x.

○: No printing unevenness.

△: partly present.

X: Printing nonuniformity is large.

The presence or absence of a pinhole was evaluated by (circle) and (x).

○: almost no pinholes.

×: many pinholes

Whether cratering was evaluated by (circle) or (x).

○: almost no cratering.

X: Many craters.

 As is apparent from the results shown in Table 2, the paste according to the composition of the present invention has excellent printability compared to the paste of the comparative composition, and can form a coating film without a pinhole. By injecting 5 mass% or more, it became clear that plate | board separation became favorable and it is useful for formation of a highly precise electrode while being a large screen.

1 is a partially exploded perspective view of an AC type PDP of a surface discharge method.

<Brief description of symbols for the main parts of the drawings>

1: front glass substrate

2a, 2b: display electrode

3a, 3b: transparent electrode

4a, 4b: bus electrode

5: transparent dielectric layer

6: protective layer

10: black pattern

11: back glass substrate

12: rib

13: address electrode

14a, 14b, 14c: phosphor film

100: front substrate for PDP 100

Claims (4)

It is a photosensitive paste containing (A) organic binder, (B) photopolymerizable monomer, (C) photoinitiator, (D) inorganic fine particle, (E) organic solvent, and (F) additive, and in organic solvent (E) The photosensitive paste containing the high boiling point organic solvent whose boiling point is 210 degreeC or more, and containing 1 type (s) or 2 or more types of dispersing agents chosen from an amine type, phosphorus type, and carboxylic acid type dispersing agent with an acryl-type leveling agent as an additive (F). The photosensitive paste of Claim 1 whose content rate of the high boiling point organic solvent of boiling point 210 degreeC or more contained in the organic solvent (E) is 5 mass% or more with respect to the photosensitive paste whole quantity. The photosensitive paste of Claim 1 containing diethylene glycol monoethyl ether acetate as a high boiling point organic solvent of boiling point 210 degreeC or more in the organic solvent (E). A plasma display panel having a fired product pattern formed of a fired product of the photosensitive paste according to any one of claims 1 to 3.

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