JP2009149745A - Paste composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a past composition containing an inorganic oxide of excellent dispersability allowing storage for a long period while restraining viscosity from increasing, and hardly sedimentation-separating the inorganic oxide. <P>SOLUTION: This past composition includes the inorganic oxide (A), a water-soluble dispersant (B) having 20 mgKOH/g or more of amine value and 30 mgKOH/g or more of acid number, and an organic binder (C). <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an improvement of a paste composition containing an inorganic oxide.

  Paste compositions containing inorganic oxides such as black pigments are widely used for paints, inks, toners, rubber / plastics, electronic materials and the like.

  In applications such as electronic materials, it is particularly required to have a low-viscosity paste containing an inorganic oxide such as a finely divided black pigment at a high concentration so that it can be easily mixed with other materials. (Patent Documents 1 and 2).

  In recent years, a paste composition containing an inorganic oxide such as a black pigment has been increasingly demanded to have a higher concentration. Even when the paste composition is stored for a long period of time, the viscosity does not increase and sedimentation does not easily occur. The demand for paste compositions with high (viscosity) stability has increased.

In addition, the conventional paste composition increases in viscosity when stored for a long period of time, and when it contains an inorganic oxide such as a high concentration of black pigment, there is a problem that a development residue is likely to be generated in the coating film using this paste composition. there were.
JP 2005-289653, problems to be solved by the invention, etc. JP 2006-306710, problems to be solved by the invention

  The problem of the present invention is that even a paste composition containing a high concentration of an inorganic oxide such as a finely divided black pigment can be stably stored for a long period of time while suppressing an increase in viscosity. An object of the present invention is to provide an inorganic oxide-containing paste composition that is less susceptible to sedimentation separation and has excellent dispersibility.

  Another object of the present invention is to provide a paste composition in which a development residue does not occur in a coating film even when an inorganic oxide such as a black pigment is contained at a high concentration.

  As a result of intensive studies to solve the above-mentioned problems, the present inventors, as a dispersant for a paste composition for dispersing an inorganic oxide such as a black pigment, have an acid value of 30 mgKOH / g or more and an amine value of 20 mgKOH. The present inventors have found that the above-mentioned problems can be solved by using a water-soluble amphoteric dispersant that is greater than or equal to / g, and the present invention has been completed.

  That is, the paste composition of the present invention that can solve the above problems is as follows.

(1) Inorganic oxide (A), water-soluble dispersant (B) having an amine value and an acid value, an amine value of 20 mgKOH / g or more, and an acid value of 30 mgKOH / g or more, organic binder (C) A paste composition containing

(2) The paste composition according to (1), wherein the inorganic oxide (A) is a black inorganic oxide.

(3) The paste composition according to (1) or (2), wherein the water-soluble dispersant (B) has a pH of 6.0 to 10.0 in a 10% by mass aqueous solution of the dispersant.

(4) A fired product pattern formed on a substrate, comprising a fired product of the paste composition according to any one of (1) to (3).

  According to the present invention, since a water-soluble dispersant having an amine value and an acid value is used, the viscosity is increased even in a paste composition containing a high concentration of an inorganic oxide such as a finely divided black pigment. It is possible to provide an inorganic oxide-containing paste composition having excellent dispersibility, which can be stably stored for a long period of time while suppressing precipitation, and is less likely to cause sedimentation and separation of the inorganic oxide.

Hereinafter, the paste composition of the present invention will be described in detail.
Inorganic oxide (A)
Examples of the inorganic oxide include black inorganic oxide composed of at least one of nickel, cobalt, and manganese, glass powder composed of inorganic oxide mainly composed of lead oxide, bismuth oxide, zinc oxide, and the like. It is done. Specifically, as the black inorganic oxide, cobalt tetroxide, Ni: 0 to 50% by mass, Co: 0 to 90% by mass, and Mn: nickel cobalt manganese composite in the range of 10 to 70% by mass An oxide is mentioned.

  Among the inorganic oxides, the black inorganic oxide preferably has a maximum primary particle size of 1 μm or less.

  When the maximum primary particle size of the black inorganic oxide is larger than 1 μm, the inorganic oxide particles in the paste are liable to settle and separate, and when stored for a long time, the organic binder and the inorganic oxide in the paste are easily separated. It is difficult to become a paste with high dispersibility that is stable for a long time.

  Among the black inorganic oxides, tribasic cobalt tetroxide is obtained by firing a cobalt hydroxide at about 650 ° C. according to a conventional method, and pulverizing after firing.

  The nickel cobalt manganese composite oxide can be prepared by firing an oxyhydroxide or hydroxide of nickel cobalt manganese. Specifically, a nickel-cobalt-manganese hydroxide coprecipitate obtained by adding an alkali hydroxide to a metal salt mixed aqueous solution using a water-soluble salt of nickel, cobalt, and manganese and neutralizing it as a raw material is used. . If this raw material is used, an arbitrary composition can be uniformly dispersed at the atomic level. Then, the nickel cobalt manganese composite oxide can be obtained by firing the hydroxide coprecipitate at, for example, 500 ° C. to 800 ° C. In this case, the primary particle diameter of the nickel cobalt manganese composite oxide can be controlled by adjusting the firing conditions and the like. Next, the black inorganic oxide can be used after being pulverized by a ball mill, a pin mill, a jet mill or the like.

  In consideration of dispersibility and blackness, such a black inorganic oxide is preferably 10 to 100 parts by mass, more preferably 30 to 60 parts by mass with respect to 100 parts by mass of the organic binder.

  Next, the glass powder which is an inorganic oxide can be mix | blended for the adhesive improvement of the pattern after baking. The glass powder preferably has a glass transition point (Tg) of 300 to 500 ° C. and a glass softening point (Ts) of 400 to 600 ° C. From the viewpoint of resolution, it is preferable to use glass powder having an average particle size of 20 μm or less, preferably 5 μm or less.

  This glass powder can be mix | blended in the ratio of 200 mass parts or less with respect to 100 mass parts of inorganic components other than glass powder for the adhesive improvement of the pattern after baking.

Water-soluble dispersant (B)
The water-soluble dispersant used in the present invention has an acid value of 30 mgKOH / g or more and an amine value of 20 mgKOH / g or more. By using such a dispersant, a long-term paste having high dispersibility can be obtained. For long-term stable dispersibility, it is essential that both are above the above lower limit. When only one of the acid value and amine value is above the lower limit and the other is less than the lower limit, only one of the numerical values is equivalent. Even if it is increased, the solvent of the inorganic oxide slurry is easily separated from the inorganic oxide during long-term storage of the paste composition, and it is difficult to obtain a paste having high dispersibility that is stable for a long time. As a result, developability deteriorates and a residue is generated.

  The dispersant (B) used in the present invention is water-soluble. The reason is that if the dispersant is not water-soluble, when the inorganic oxide slurry is stored for a long period of time, separation between the solvent in the slurry and the inorganic oxide is likely to occur, and the inorganic oxide is highly stable for a long period of time. This is because it is difficult to form a slurry.

  The dispersant preferably has a 10% by mass aqueous solution pH of 6.0 to 10.0. When the pH of the 10% by weight aqueous solution of the dispersing agent is less than 6.0, the inorganic oxide in the black inorganic oxide paste reacts with the dispersing agent. May cause dissolution. On the other hand, when the pH of the 10% by weight aqueous solution of the dispersant is higher than 10.0, the black inorganic oxide and the organic binder are easily separated during long-term storage of the paste, and the black inorganic oxide paste having high long-term dispersibility. Not.

Examples of such a water-soluble dispersant (B) include Disperbyk-180, Disperbyk-187, and Disperbyk-191 (all are trade names manufactured by BYK Chemie).
The water-soluble dispersant (B) is preferably 0.1 to 20 parts by mass, more preferably 1 to 6 parts by mass with respect to 100 parts by mass of the organic binder (C) in consideration of dispersibility and blackness. And

Organic binder (C)
Next, the organic binder (C) includes a carboxyl group-containing resin, specifically, a carboxyl group-containing photosensitive resin having an ethylenically unsaturated double bond and an ethylenically unsaturated double bond. Any carboxyl group-containing resin that is not used can be used. Examples of the resin (which may be either an oligomer or a polymer) that can be suitably used include the following.

(1) A carboxyl group-containing resin obtained by copolymerizing (a) an unsaturated carboxylic acid and (b) a compound having an unsaturated double bond (2) (a) an unsaturated carboxylic acid and (b) unsaturated A carboxyl group-containing photosensitive resin obtained by adding an ethylenically unsaturated group as a pendant to a copolymer of a compound having a double bond (3) (c) a compound having an epoxy group and an unsaturated double bond ( b) A carboxyl group obtained by reacting a copolymer of a compound having an unsaturated double bond with (a) an unsaturated carboxylic acid, and reacting the resulting secondary hydroxyl group with (d) a polybasic acid anhydride. Containing photosensitive resin (4) (e) a copolymer of an acid anhydride having an unsaturated double bond and (b) a compound having an unsaturated double bond, (f) having a hydroxyl group and an unsaturated double bond Obtained by reacting compounds Carboxyl group-containing photosensitive resin (5) (g) A carboxyl obtained by reacting an epoxy compound with (h) an unsaturated monocarboxylic acid and reacting the resulting secondary hydroxyl group with (d) a polybasic acid anhydride Group-containing photosensitive resin (6) (b) An epoxy group of a copolymer of an unsaturated double bond and a glycidyl (meth) acrylate copolymer, (i) having one carboxyl group in one molecule, ethylene (D) a carboxyl group-containing resin (7) (j) obtained by reacting an organic acid not having a polymerizable unsaturated bond and reacting the resulting secondary hydroxyl group with (d) a polybasic acid anhydride (d) ) A carboxyl group-containing resin obtained by reacting a polybasic acid anhydride (8) (j) A carboxyl group-containing resin obtained by reacting a hydroxyl group-containing polymer with (d) a polybasic acid anhydride, (c) Epoxy Carboxyl group-containing photosensitive resin obtained by further reacting a group and a compound having an unsaturated double bond The carboxyl group-containing photosensitive resin and the carboxyl group-containing resin as described above may be used alone or in combination. However, in any case, these are preferably blended in a proportion of 10 to 80% by mass of the total amount of the paste composition. When the blending amount of these organic binders is less than the above range, the distribution of the resin in the coating film to be formed tends to be non-uniform, and it is difficult to obtain sufficient photocurability and photocuring depth. Patterning by 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 each 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, and 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. When the molecular weight of the resin is lower than 1,000, the adhesion of the coating during development is adversely affected. On the other hand, when the molecular weight is higher than 100,000, development defects are liable to occur. 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. This is not preferable because dissolution of the exposed portion occurs. Further, in the case of a carboxyl group-containing photosensitive resin, if the double bond equivalent of the photosensitive resin is less than 350, a residue is likely to remain at the time of baking, whereas if it is greater than 2,000, a work margin at the time of development. Is narrow, and a high exposure amount is required at the time of photocuring.

Photopolymerizable monomer
Next, the paste composition of the present invention can be blended with a photopolymerizable monomer in order to promote the photocurability and developability of the paste composition. 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 amount of such a photopolymerizable monomer is suitably 20 to 100 parts by mass per 100 parts by mass of the organic binder (carboxyl group-containing photosensitive resin and / or carboxyl group-containing resin) (C). When the blending amount of the photopolymerizable monomer is less than the above range, it becomes difficult to obtain sufficient photocurability of the paste composition. On the other hand, when the amount exceeds the above range, the surface portion is larger than the deep portion of the coating film. Since the photo-curing of the resin becomes faster, uneven curing tends to occur.

Photopolymerization initiator
Next, this invention can mix | blend a photoinitiator. Examples of the photopolymerization initiator include benzoin and benzoin alkyl ethers such as benzoin, benzoin methyl ether, benzoin ethyl ether, and benzoin isopropyl ether; acetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxy-2- Acetophenones such as phenylacetophenone and 1,1-dichloroacetophenone; 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1- Aminoacetophenones such as (4-morpholinophenyl) -butanone-1; anthraquinones such as 2-methylanthraquinone, 2-ethylanthraquinone, 2-t-butylanthraquinone, 1-chloroanthraquinone; 2,4-dimethyl Thioxanthones such as luthioxanthone, 2,4-diethylthioxanthone, 2-chlorothioxanthone, 2,4-diisopropylthioxanthone; ketals such as acetophenone dimethyl ketal and benzyldimethyl ketal; benzophenones such as benzophenone; or xanthones; , 6-Dimethoxybenzoyl) -2,4,4-pentylphosphine oxide, bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, ethyl-2 Phosphine oxides such as 1,4,6-trimethylbenzoylphenyl phosphinate; various peroxides, etc. These known photopolymerization initiators may be used alone or in combination of two or more. It can be used Te. The mixing ratio of these photopolymerization initiators is suitably 1 to 30 parts by mass, preferably 5 parts per 100 parts by mass of the organic binder (carboxyl group-containing photosensitive resin and / or carboxyl group-containing resin) (C). ˜20 parts by mass.

  In addition, the photopolymerization initiator includes tertiary amines 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 photosensitizers. Furthermore, when a deeper photocuring depth is required, a titanocene photopolymerization initiator such as Irgacure 784 manufactured by Ciba Specialty Chemicals, which starts radical polymerization in the visible region, and leuco dyes are cured as necessary. It can be used in combination as an auxiliary agent.

  The paste composition of the present invention can be blended with an inorganic filler or glass powder. However, when a large amount of inorganic filler or glass powder is blended, the storage stability of the resulting paste composition is poor, and gelation or fluidity is caused. There is a tendency that the coating workability is deteriorated due to the decrease in. Accordingly, in the composition of the present invention, in order to improve the storage stability of the composition, a compound effective for complexing or forming a salt with a metal or oxide powder as a component of an inorganic filler or glass powder, such as an organic acid. It is preferable to add a stabilizer such as The amount of the stabilizer added is preferably 0.1 to 10 parts by mass per 100 parts by mass of the inorganic filler or glass powder.

Other ingredients
In the present invention, an appropriate amount of an organic solvent can be blended as a diluent for pasting the composition or a diluent for adjusting the viscosity according to various coating steps. 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 paste composition of the present invention further contains other additives such as silicone-based and acrylic-based antifoaming / leveling agents, silane coupling agents for improving the adhesion of coating films, and the like. 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.

Use of paste composition
The paste composition of the present invention is applied to a substrate, for example, a glass substrate as a front substrate of a PDP by an appropriate application method such as a screen printing method, a bar coater, a blade coater, etc., and then a hot air circulation type to obtain touch dryness For example, the organic solvent is evaporated by drying at about 60 to 120 ° C. for about 5 to 40 minutes in a drying oven, a far-infrared drying oven or the like, and a tack-free coating film is obtained. Thereafter, selective exposure, development, and baking are performed to form a predetermined pattern. Moreover, it can also form into a film form and can laminate on a board | substrate.

  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 / cm2.

  As the development process, 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 pattern. In addition, it is preferable to set the temperature increase rate at this time to 20 degrees C / min or less.

  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.

  Using the various additives presented in Table 1, the organic binder obtained in the following synthesis example, and the glass slurry obtained in the following production example, a paste was formed and evaluated.

Synthesis Example: (Synthesis of Organic Binder (C-1))
In a flask equipped with a thermometer, stirrer, dropping funnel, and reflux condenser, diethylene glycol monoethyl ether acetate as a solvent and azobisisobutyronitrile as a catalyst are added and heated to 80 ° C. in a nitrogen atmosphere. A monomer mixed with methacrylic acid: 0.4 mol and methyl methacrylate: 0.6 mol in molar ratio was added dropwise over about 2 hours, and the mixture was further stirred for 1 hour, and then the temperature was raised to 115 ° C. to deactivate. A resin solution was obtained. After cooling this resin solution, tetrabutylammonium bromide was used as a catalyst at 95 to 115 ° C. for 30 hours, and butyl glycidyl ether: 0.4 mol was added with an equivalent amount of carboxyl group of the obtained resin and addition reaction. And cooled. Further, 0.26 mol of tetrahydrophthalic anhydride was added to the OH group of the obtained resin under the conditions of 95 to 105 ° C. for 8 hours, cooled and taken out, and the organic binder (C -1) was obtained.

Production Example: Production of Glass Slurry As glass powder, Bi ₂ O ₃ : 50%, B ₂ O ₃ : 16%, ZnO: 14%, SiO ₂ : 2%, BaO: 18%, coefficient of thermal expansion α ₃₀₀ = The thing of 86 * 10 < ^-7 > / degreeC and the glass softening point 501 degreeC was used.

Further, grinding in a bead mill, the Mitsui Mining using manufactured SC50 Co., media size using the ZrO ₂ beads made of 0.3～0.8Mmfai, at a rotation speed of 2,000～3,300Rpm,. 3 to Milling was carried out for 9 hours.

  In addition, the Horiba laser diffraction / scattering type particle size distribution measuring device LA-920 was used for the particle size measurement.

  After roughly pulverizing the glass powder, it was filtered with a 300 mesh screen, and 70 parts by mass of this glass powder and 29.16 parts by mass of 2,2,4-trimethyl-1,3-pentanediol monobutyrate were added thereto. As a dispersant, 0.14 parts by mass of BYK-410 and 0.7 parts by mass of BYK-182 were added and finely pulverized with a bead mill. D50: 1.0 μm, Dmax: 3.9 μm glass powder content Produced a 70% by weight slurry.

  The produced glass slurry was further filtered through a SUS 200 × 1400 twill mat mesh, but no change was observed in the particle size distribution.

<Composition Example 1>
Organic binder (C-1) 100.0 parts Tripropylene glycol monomethyl ether 90.0 parts Trimethylolpropane triacrylate 30.0 parts Diventaerythritol hexaacrylate 15.0 parts Aronix M7100 (polyester acrylate manufactured by Toagosei Co., Ltd.) 50 0.0 parts Modaflow (Nippon Monsanto Antifoam) 3.0 parts Phosphate 1.0 parts Glass slurry 43.0 parts Cobalt tetraoxide 47.0 parts
10.0 parts of 2-methyl-1- (4-methylthiophenyl) -2-morpholinopropan-1-one
2,4-Diethylthioxanthone 3.0 parts
4,4-bis (diethylamino) benzophenone 1.0 part γ-methacryloxypropyltrimethoxysilane 3.0 parts
Disperbyk-180 (manufactured by Big Chemie Japan; trade name) 2.4 parts Composition Example 2
Pasting was carried out with the same composition as in Composition Example 1 except that Disperbyk-180 was replaced with Disperbyk187 (manufactured by BYK-Chemical Japan; trade name).

Composition Example 3
Pasting was carried out with the same composition as in Composition Example 1 except that Disperbyk-180 was replaced with Disperbyk191 (manufactured by BYK-Chemical Japan; trade name).

Comparative composition example 1
Pasting was carried out with the same composition as in Composition Example 1 except that Disperbyk-180 was replaced with Disperbyk182 (manufactured by BYK-Chemical Japan; trade name).

Comparative composition example 2
Pasting was carried out with the same composition as in Composition Example 1 except that Disperbyk-180 was replaced with Disperbyk163 (manufactured by Bicchem Japan);

Comparative composition example 3
Pasting was carried out with the same composition as in Composition Example 1 except that Disperbyk-180 was replaced with Disperbyk185 (manufactured by BYK-Chemical Japan; trade name).

Comparative composition example 4
Pasting was carried out with the same composition as in Composition Example 1 except that Disperbyk-180 was replaced with Disperbyk140 (manufactured by Bicchem Japan);

Comparative composition example 5
Pasting was performed with the same composition as in Composition Example 1 except that Disperbyk-180 was replaced with Disperbyk171 (manufactured by Bicchem Japan);

Comparative composition example 6
Pasting was carried out with the same composition as in Composition Example 1 except that Disperbyk-180 was replaced with Disperbyk110 (manufactured by Bicchem Japan);

Paste dispersion
Each paste component of Composition Examples 1 and 2 and Comparative Composition Examples 1 to 7 is blended in a plastic container and stirred with a dissolver at 500 rpm for 10 minutes. Thereafter, the paste was prepared by performing kneaded meat twice with three ceramic rolls.

  With respect to each of the photosensitive pastes of the composition examples and comparative composition examples thus obtained, test pieces were prepared, and development residues were evaluated. The preparation method and evaluation method of the test piece are as follows. The stability of the paste over time was also confirmed.

(Test piece preparation method)
Each photosensitive paste for evaluation was applied to the entire surface of a glass substrate (Asahi Glass Co., Ltd., PD200) on which an ITO film was formed, using a 300-mesh polyester screen. The film was dried for 30 minutes at a temperature of about 4 μm. Next, using an ultra-high pressure mercury lamp as a light source, pattern exposure was performed through a negative mask so that the integrated light amount on the dried coating film was 100 mJ / cm ^2, and then 0.4 wt% Na ₂ CO _{3 at} a liquid temperature of 25 ° C. Development was performed using an aqueous solution and washed with water. Thus, a coating film pattern was formed to prepare a test piece.

(Development residue)
The test piece was observed with an optical microscope, and a development residue (development residue) was confirmed. In Table 2, the development residue at this time is defined as an initial residue.

(Stability over time)
Viscosity stability and development residue were confirmed for each paste after standing for 1 week in a thermostatic bath at 30 ° C. In Table 2, the development residue at this time is defined as a time-dependent residue.
The evaluation results are shown in Table 2.

  As is clear from the above evaluation results, the paste composition according to the present invention suppresses an increase in viscosity even if it is a paste composition containing a high concentration of inorganic oxides such as atomized black pigments. It was confirmed that an inorganic oxide-containing paste composition excellent in dispersibility can be provided that can be stably stored for a long period of time, and that sedimentation and separation of the inorganic oxide hardly occur.

Claims (4)

Contains an inorganic oxide (A), a water-soluble dispersant (B) having an amine value and an acid value, an amine value of 20 mgKOH / g or more, and an acid value of 30 mgKOH / g or more, and an organic binder (C) , Paste composition. The paste composition according to claim 1, wherein the inorganic oxide (A) is a black inorganic oxide. The paste composition according to claim 1 or 2, wherein the water-soluble dispersant (B) has a pH of 6.0 to 10.0 in a 10 mass% aqueous solution of the dispersant. A fired product pattern formed on a substrate, comprising a fired product of the paste composition according to claim 1.