(METH)acrylic resin particles, vehicle composition, slurry composition, and method for manufacturing electronic components

Abstract

The present invention provides (meth)acrylic resin particles that have excellent low-temperature decomposition properties, and when used as a binder for dispersing inorganic particles, are capable of preventing deterioration caused by oxidation of inorganic particles such as copper, and can be used to manufacture an inorganic-particle-dispersed slurry composition that has particularly excellent dispersibility of fine inorganic particles. In addition, provided are (meth)acrylic resin particles that, by being used as a binder for external electrodes of a layered ceramic capacitor, enable manufacture of a layered ceramic capacitor having excellent reliability. Furthermore, provided are a vehicle composition, a slurry composition, and a method for manufacturing electronic components. The (meth)acrylic resin particles of the present invention have a weight average molecular weight of 100,000-1,000,000 and a weight concentration of S atoms of 0.03-2.50 wt%.

Description

(Meth)acrylic resin particles, vehicle composition, slurry composition, and method for producing electronic components

[0001] The present invention relates to (meth)acrylic resin particles, a vehicle composition, a slurry composition, and a method for producing electronic components.

[0002] A known multilayer ceramic capacitor has a structure comprising a laminate in which dielectric layers and internal electrodes are alternately stacked, and a pair of external electrodes sandwiching the laminate. The external electrodes are formed by applying a conductive paste for the external electrodes to the surface of the laminate and sintering it.

[0003] In recent years, as multilayer ceramic capacitors have become smaller, the inorganic particles used in external electrodes have also become smaller. However, these particles tend to aggregate in the paste, and this aggregation can lead to voids remaining during the degreasing and firing processes, or can reduce the dispersibility of the inorganic particles when the capacitor is made into a multilayer ceramic capacitor, resulting in a deterioration in the electrical characteristics of the product.

[0004] Ethyl cellulose, for example, is commonly used as a binder resin for external electrodes. For example, Patent Document 1 discloses a method for efficiently dispersing ceramic powder in a configuration using such a binder. Specifically, the method discloses a method in which ceramic powder such as calcium titanate is first crushed in a solvent such as ethanol, and then a resin such as polyvinyl butyral resin or ethyl cellulose resin is added. Furthermore, Patent Document 2 discloses a method in which an acrylic resin or the like is used as a binder.

[0005] JP 2011-84433 A JP 2021-111525 A

[0006] However, the polyvinyl acetal resin described in Patent Document 1 has a high decomposition temperature, which makes it unsuitable for applications where low-temperature firing is desirable, such as applications using easily oxidized metals such as copper or low-melting-point glass. Patent Document 2 also describes the use of an acrylic resin, but when fine inorganic particles with an average particle size of less than 1 μm are used, there is a problem that dispersibility deteriorates. Furthermore, the acrylic resin described in Patent Document 2 has a problem that deterioration due to oxidation occurs during degreasing, which requires high firing temperatures.

[0007] The present invention aims to provide (meth)acrylic resin particles that have excellent low-temperature decomposition properties, can prevent oxidation-induced deterioration of inorganic particles such as copper when used as a binder for inorganic particle dispersion, and can be used to prepare an inorganic particle-dispersed slurry composition that is particularly excellent in dispersibility of fine inorganic particles. Another object of the present invention is to provide (meth)acrylic resin particles that can be used, in particular, as a binder for the external electrodes of a multilayer ceramic capacitor to produce a multilayer ceramic capacitor with excellent reliability. Another object of the present invention is to provide a vehicle composition, a slurry composition, and a method for producing an electronic component.

[0008] Disclosure (1) is (meth)acrylic resin particles having a weight-average molecular weight of 100,000 or more and 1,000,000 or less and a weight concentration of S atoms of 0.03 wt % or more and 2.50 wt % or less. Disclosure (2) is (meth)acrylic resin particles of disclosure (1) having a weight concentration of COOH groups of 0.06 wt % or more and 3.00 wt % or less. Disclosure (3) is (meth)acrylic resin particles of disclosure (1) or (2) having a weight concentration of K atoms of 0.010 wt % or more and 1.000 wt % or less. Disclosure (4) is (meth)acrylic resin particles in any combination with any of disclosures (1) to (3) in which the content of components derived from acrylic monomers is 5 wt % or less. Disclosure (5) is (meth)acrylic resin particles in any combination with any of disclosures (1) to (4) in which the average particle diameter is 0.1 μm or more and 1.0 μm or less. The present disclosure (6) is a vehicle composition containing (meth)acrylic resin particles according to any one of the present disclosures (1) to (5) and a solvent containing an organic solvent. The present disclosure (7) is the vehicle composition according to the present disclosure (6), in which the solvent further contains water in an amount of 100 ppm by weight or more and 40,000 ppm by weight or less. The present disclosure (8) is the vehicle composition according to the present disclosure (6) or (7), in which the organic solvent contains a compound having two or more OH groups, and the content of the compound having two or more OH groups in the solvent is 10% by weight or more and 50% by weight or less. The present disclosure (9) is a slurry composition containing the vehicle composition according to any one of the present disclosures (6) to (8), inorganic particles, and a dispersant. The present disclosure (10) is a method for producing an electronic component using the slurry composition according to the present disclosure (9). The present invention is described in detail below.

[0009] The present inventors have discovered that (meth)acrylic resin particles having a predetermined weight-average molecular weight and a weight concentration of S atoms have excellent low-temperature decomposition properties and, when used as a binder for dispersing inorganic particles, can prevent deterioration of inorganic particles such as copper due to oxidation. They also discovered that the use of such a (meth)acrylic resin can produce an inorganic particle-dispersed slurry composition that is particularly excellent in dispersibility of fine inorganic particles. Furthermore, they discovered that the use of such (meth)acrylic resin particles as a binder for the external electrodes of a multilayer ceramic capacitor can produce a multilayer ceramic capacitor with excellent reliability, leading to the completion of the present invention.

[0010] The (meth)acrylic resin particles have a weight-average molecular weight (Mw) of 100,000 or more and 1,000,000 or less. By setting the weight-average molecular weight within this range, the inorganic particles can be more dispersible when prepared into an inorganic particle-dispersed slurry composition. Furthermore, the composition has sufficient viscosity, thereby improving printability. The weight-average molecular weight (Mw) is preferably 150,000 or more, and particularly preferably 170,000 or more. The weight-average molecular weight (Mw) is preferably 900,000 or less, more preferably 800,000 or less, even more preferably 700,000 or less, and particularly preferably 500,000 or less. Furthermore, the ratio (Mw / Mn) of the weight-average molecular weight (Mw) to the number-average molecular weight (Mn) of the (meth)acrylic resin particles is preferably 8 or less, more preferably 6 or less, and even more preferably 5 or less. The weight-average molecular weight (Mw) and the number-average molecular weight (Mn) are average molecular weights calculated in terms of polystyrene, and can be obtained by GPC measurement using, for example, a column LF-804 (manufactured by Showa Denko KK).

[0011] The weight concentration of S atoms contained in the (meth)acrylic resin particles is 0.03 wt% or more and 2.50 wt% or less. By setting it in this range, when an inorganic particle dispersion slurry composition is prepared, the inorganic particles can be particularly well dispersed. The weight concentration of S atoms is preferably 0.30 wt% or more, preferably 2.00 wt% or less, more preferably 0.50 wt% or more, more preferably 1.80 wt% or less, even more preferably 0.70 wt% or more, and even more preferably 1.50 wt% or less. The weight concentration of S atoms means the ratio of the weight of S atoms in the (meth)acrylic resin structure to the weight of the (meth)acrylic resin particles, and can be calculated based on the following formula. The above value is rounded to two decimal places. Weight concentration of S atoms contained in (meth)acrylic resin particles=[(weight of S atoms contained in all monomers+weight of S atoms contained in all chain transfer agents+weight of S atoms contained in all polymerization initiators) / (weight of all monomers+weight of all chain transfer agents+weight of all polymerization initiators)]×100. The weight concentration of S atoms can also be determined by ICP-AES (inductively coupled plasma-atomic emission spectroscopy).

[0012] The weight concentration of COOH groups contained in the (meth)acrylic resin particles is preferably 0.06 wt% or more, and preferably 3.00 wt% or less. This range has the advantage of providing particularly excellent dispersibility in inorganic particles. The weight concentration of COOH groups is more preferably 0.50 wt% or more, more preferably 2.70 wt% or less, even more preferably 1.00 wt% or more, and even more preferably 2.50 wt% or more. The weight concentration of COOH groups refers to the ratio of the weight of COOH groups in the (meth)acrylic resin structure to the weight of the (meth)acrylic resin particles, and can be calculated based on the following formula: The above values ​​are rounded to two decimal places. Weight concentration of COOH groups contained in (meth)acrylic resin particles=[(weight of COOH groups contained in all monomers+weight of COOH groups contained in all chain transfer agents+weight of COOH groups contained in all polymerization initiators) / (weight of all monomers+weight of all chain transfer agents+weight of all polymerization initiators)]×100. The weight concentration of COOH groups can also be determined by ESCA analysis using a gas-phase chemical modification method.

[0013] The weight concentration of K atoms contained in the (meth)acrylic resin particles is preferably 0.001 wt% or more and preferably 1.500 wt% or less. Setting the weight concentration in this range improves storage stability. The weight concentration of K atoms is more preferably 0.005 wt% or more and more preferably 1.200 wt% or less. The weight concentration of K atoms means the ratio of the weight of K atoms in the (meth)acrylic resin structure to the weight of the (meth)acrylic resin particles, and can be calculated based on the following formula: The above value is rounded to three decimal places. Weight concentration of K atoms contained in (meth)acrylic resin particles = [(weight of K atoms contained in all monomers + weight of K atoms contained in all chain transfer agents + weight of K atoms contained in all polymerization initiators) / (weight of all monomers + weight of all chain transfer agents + weight of all polymerization initiators)] × 100. The weight concentration of K atoms can also be measured using an atomic absorption spectrophotometer.

[0014] The weight concentration of OH groups contained in the (meth)acrylic resin particles is preferably 0.05 wt% or more, preferably 3.00 wt% or less, more preferably 0.08 wt% or more, more preferably 2.50 wt% or less, even more preferably 0.10 wt% or more, and even more preferably 2.00 wt% or less. Being within the above range improves storage stability, viscosity stability, and decomposability. The weight concentration of OH groups means the ratio of the weight of OH groups in the (meth)acrylic resin structure to the weight of the (meth)acrylic resin particles, and can be calculated based on the following formula. The above value is rounded to two decimal places. Weight concentration of OH groups contained in (meth)acrylic resin particles=[(weight of OH groups contained in all monomers+weight of OH groups contained in all chain transfer agents+weight of OH groups contained in all polymerization initiators) / (weight of all monomers+weight of all chain transfer agents+weight of all polymerization initiators)]×100. The weight concentration of OH groups can also be determined by ESCA analysis using a gas-phase chemical modification method.

[0015] Furthermore, the ratio of the weight concentration of COOH groups to the weight concentration of S atoms contained in the (meth)acrylic resin particles (weight concentration of COOH groups / weight concentration of S atoms) is preferably 0.03 or more and 3.00 or less, more preferably 0.05 or more and more preferably 1.00 or less.

[0016] The ratio of the weight concentration of OH groups to the weight concentration of S atoms contained in the (meth)acrylic resin particles (weight concentration of OH groups / weight concentration of S atoms) is preferably 0.10 or more and 3.00 or less, more preferably 0.15 or more and more preferably 1.20 or less.

[0017] The ratio of the weight concentration of K atoms to the weight concentration of S atoms contained in the (meth)acrylic resin particles (weight concentration of K atoms / weight concentration of S atoms) is preferably 0.01 or more and 1.50 or less, more preferably 0.05 or more and 1.20 or less.

[0018] The average particle size of the (meth)acrylic resin particles is preferably 0.1 μm or more and preferably 1.0 μm or less. By setting the average particle size within this range, the solubility of the (meth)acrylic resin particles can be further improved. The average particle size is more preferably 0.2 μm or more, more preferably 0.9 μm or less, even more preferably 0.3 μm or more, and even more preferably 0.8 μm or less. The average particle size can be determined, for example, by measuring the volume average particle size using a laser diffraction / scattering particle size distribution analyzer. The average particle size can be adjusted by the amount of polymerization initiator. For example, a high content of polymerization initiator tends to result in a small average particle size, while a low content of polymerization initiator tends to result in a large average particle size.

[0019] The (meth)acrylic resin particles preferably contain a segment derived from a (meth)acrylic acid ester having an ester substituent with 8 or less carbon atoms. The term "the ester substituent has 8 or less carbon atoms" refers to the total number of carbon atoms in the (meth)acrylic acid ester other than the carbon atoms constituting the (meth)acryloyl group being 8 or less. In this specification, the term "(meth)acrylic acid ester having 8 or less carbon atoms in the ester substituent" refers to a (meth)acrylic acid ester other than a (meth)acrylic acid ester having a glycidyl group, as described below. Examples of the (meth)acrylic acid ester having 8 or less carbon atoms in the ester substituent include (meth)acrylic acid esters having a linear, branched, or cyclic alkyl group. Examples of the (meth)acrylic acid ester having a linear alkyl group include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, and n-butyl (meth)acrylate. Examples of the (meth)acrylic acid ester having a branched alkyl group include isopropyl (meth)acrylate, t-butyl (meth)acrylate, isobutyl (meth)acrylate, and 2-ethylhexyl (meth)acrylate. Examples of the (meth)acrylic acid ester having a cyclic alkyl group include cyclohexyl (meth)acrylate and benzyl (meth)acrylate. Furthermore, examples of the (meth)acrylic acid ester having an ester substituent with 8 or fewer carbon atoms include (meth)acrylates having a hydroxyl group or a carboxyl group, such as 2-hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, hydroxybutyl (meth)acrylate, and (meth)acrylic acid. Of these, (meth)acrylic acid esters having a linear alkyl group and (meth)acrylic acid esters having a branched alkyl group are preferred. Furthermore, methyl methacrylate, ethyl methacrylate, and isobutyl methacrylate are more preferred. Furthermore, a combination of a (meth)acrylic acid ester having a linear alkyl group and a (meth)acrylic acid ester having a branched alkyl group is preferred.

[0020] The (meth)acrylic acid ester having an ester substituent with 8 or less carbon atoms may be a (meth)acrylic acid ester having an ester substituent with 1 to 4 carbon atoms, or a (meth)acrylic acid ester having an ester substituent with 5 to 8 carbon atoms. Of these, a (meth)acrylic acid ester having an ester substituent with 1 to 4 carbon atoms is preferred.

[0021] The content of the segment derived from the (meth)acrylic acid ester in which the ester substituent has 8 or less carbon atoms in the (meth)acrylic resin particles is preferably 40% by weight or more, more preferably 60% by weight or more, and even more preferably 80% by weight or more. There is no particular upper limit, but it is preferably 100% by weight or less, more preferably 99% by weight or less, and even more preferably 98% by weight or less. The content of the segment in the (meth)acrylic resin particles can be calculated based on the ratio of each monomer to 100 parts by weight of raw material monomers, excluding the polymerization initiator and chain transfer agent, among the raw materials used to prepare the (meth)acrylic resin constituting the (meth)acrylic resin particles.

[0022] The content of the segment derived from the (meth)acrylic acid ester in the ester substituent having 1 to 4 carbon atoms in the (meth)acrylic resin particles is preferably 40% by weight or more, more preferably 60% by weight or more, and even more preferably 80% by weight or more. The upper limit is not particularly limited, but is, for example, 100% by weight or less.

[0023] The content of the segment derived from a (meth)acrylic acid ester having an ester substituent with 1 to 2 carbon atoms in the (meth)acrylic resin particles is preferably 35% by weight or more, more preferably 40% by weight or more, and is preferably 65% ​​by weight or less, more preferably 60% by weight or less.

[0024] The content of the segment derived from the (meth)acrylic acid ester having 5 to 8 carbon atoms in the ester substituent in the (meth)acrylic resin particles is preferably 60% by weight or less, more preferably 40% by weight or less, and even more preferably 20% by weight or less. The lower limit is not particularly limited, but is, for example, 0% by weight or more.

[0025] The content of the methyl methacrylate-derived segment in the (meth)acrylic resin particles is preferably 30% by weight or more and 60% by weight or less, more preferably 35% by weight or more and 50% by weight or less.

[0026] The content of the ethyl methacrylate-derived segment in the (meth)acrylic resin particles is preferably 10% by weight or more and 30% by weight or less, more preferably 15% by weight or more and 25% by weight or less.

[0027] The content of the isobutyl methacrylate-derived segment in the (meth)acrylic resin particles is preferably 30% by weight or more, and preferably 60% by weight or less, more preferably 35% by weight or less, and even more preferably 50% by weight or less.

[0028] The (meth)acrylic resin particles may have a segment derived from a (meth)acrylic acid ester having an ester substituent with 9 or more carbon atoms. The ester substituent preferably has 10 or more carbon atoms, and more preferably has 30 or less carbon atoms, and even more preferably has 20 or less carbon atoms.

[0029] Examples of the (meth)acrylic acid ester having an ester substituent with 9 or more carbon atoms include a (meth)acrylic acid ester having a linear or branched alkyl group with 9 or more carbon atoms, and polyalkylene glycol (meth)acrylate.

[0030] Examples of the (meth)acrylic acid ester having a linear or branched alkyl group having 9 or more carbon atoms include n-nonyl (meth)acrylate, isononyl (meth)acrylate, n-decyl (meth)acrylate, isodecyl (meth)acrylate, n-lauryl (meth)acrylate, isolauryl (meth)acrylate, n-stearyl (meth)acrylate, and isostearyl (meth)acrylate. Examples of the polyalkylene glycol (meth)acrylate include those having ethylene glycol units, propylene glycol units, butylene glycol units, and the like. The polyalkylene glycol (meth)acrylate may have an alkoxy group at the terminal, or may have an ethylhexyl group at the terminal. The polyalkylene glycol (meth)acrylate may have a linear alkylene glycol unit, or may have a branched alkylene glycol unit.

[0031] The content of the segment derived from the (meth)acrylic acid ester having 9 or more carbon atoms in the ester substituent in the (meth)acrylic resin particles is preferably 60% by weight or less, more preferably 40% by weight or less, and even more preferably 20% by weight or less. The lower limit is not particularly limited, but is, for example, 0% by weight or more.

[0032] The (meth)acrylic resin particles may have a segment derived from a (meth)acrylic acid ester having a glycidyl group, such as glycidyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate glycidyl ether, or 3,4-epoxycyclohexyl (meth)acrylate.

[0033] The content of the acrylic monomer-derived segment in the (meth)acrylic resin particles is preferably 5% by weight or less, more preferably 1% by weight or less, since a smaller content has the advantage of improving low-temperature decomposition. The lower limit is not particularly limited, but is, for example, 0% by weight or more. The acrylic monomer refers to acrylic acid and acrylic acid esters.

[0034] The glass transition temperature (Tg) of the (meth)acrylic resin particles is preferably 30°C or higher and 85°C or lower. By setting the temperature within this range, the amount of plasticizer added can be reduced and low-temperature decomposition properties can be improved. The Tg is more preferably 32°C or higher, more preferably 80°C or lower, even more preferably 42°C or higher, and even more preferably 75°C or lower. The glass transition temperature (Tg) can be measured using, for example, a differential scanning calorimeter (DSC) or the like.

[0035] The (meth)acrylic resin particles preferably have a 90 wt % decomposition temperature of 280° C. or lower, more preferably 270° C. or lower, and even more preferably 260° C. or lower, when heated from 30° C. at a rate of 5° C. / min. The lower limit is not particularly limited, and is 30° C. or higher, and the lower the temperature, the better.

[0036] Examples of methods for producing the (meth)acrylic resin particles include a method in which an organic solvent or the like is added to a raw material monomer mixture containing a (meth)acrylic acid ester or the like to prepare a monomer mixture, and a polymerization initiator and a chain transfer agent are further added to the obtained monomer mixture to copolymerize the raw material monomers. The polymerization method is not particularly limited, and examples include emulsion polymerization, suspension polymerization, bulk polymerization, interfacial polymerization, and solution polymerization. Among these, solution polymerization is preferred.

[0037] Examples of the organic solvent include toluene, ethyl acetate, butyl acetate, pentyl acetate, hexyl acetate, ethyl butyrate, butyl butyrate, pentyl butyrate, hexyl butyrate, isopropanol, methyl isobutyl ketone, methyl ethyl ketone, methyl isobutyl ketone, ethylene glycol ethyl ether, ethylene glycol monobutyl ether, ethylene glycol monoethyl ether acetate, diethylene glycol monoethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoisobutyl ether, trimethylpentanediol monoisobutyrate, butyl carbitol, butyl carbitol acetate, terpineol, terpineol acetate, dihydroterpineol, dihydroterpineol acetate, Texanol, isophorone, butyl lactate, dioctyl phthalate, dioctyl adipate, benzyl alcohol, phenylpropylene glycol, and cresol. Among these, butyl acetate, terpineol, terpineol acetate, dihydroterpineol, dihydroterpineol acetate, diethylene glycol monoethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoisobutyl ether, butyl carbitol, butyl carbitol acetate, and Texanol are preferred. Also, butyl acetate, terpineol, terpineol acetate, dihydroterpineol, and dihydroterpineol acetate are more preferred. These organic solvents may be used alone or in combination of two or more.

[0038] Examples of the polymerization initiator include t-butyl peroxypivalate, p-menthane hydroperoxide, diisopropylbenzene hydroperoxide, 1,1,3,3-tetramethylbutyl hydroperoxide, cumene hydroxyperoxide, t-butyl hydroxyperoxide, cyclohexanone peroxide, disuccinic acid peroxide, etc. Also usable are acid mixtures of imidazole-based azo compounds such as 2,2'-azobis[2-(2-imidazolin-2-yl)propane]dihydrochloride, 2,2'-azobis[2-(2-imidazolin-2-yl)propane]sulfatohydrate, and 2,2'-azobis[2-(2-imidazolin-2-yl)propane]; 2,2'-azobis(2-methylpropionamidine)dihydrochloride; 2,2'-azobis[N-(2-carboxyethyl)-2-methylpropane]; water-soluble azo compounds such as [2-methyl-N-(2-hydroxyethyl)propionamidine]tetrahydrate, 2,2'-azobis[2-methyl-N-(2-hydroxyethyl)propionamide], and 4,4'-azobis-4-cyanovaleric acid; oxoacids such as potassium persulfate (potassium peroxodisulfate), ammonium persulfate (ammonium peroxodisulfate), and sodium persulfate (sodium peroxodisulfate); and peroxides such as hydrogen peroxide, peracetic acid, performic acid, and perpropionic acid. Among these, polymerization initiators containing an S atom and polymerization initiators containing a K atom are preferably used. Furthermore, potassium persulfate, ammonium persulfate, 2,2'-azobis[2-(2-imidazolin-2-yl)propane]dihydrochloride, and 2,2'-azobis[2-methyl-N-(2-hydroxyethyl)propionamide] are preferred, and potassium persulfate and 2,2'-azobis[2-methyl-N-(2-hydroxyethyl)propionamide] are more preferred.

[0039] The amount of the polymerization initiator added is preferably 0.03 parts by weight or more and 4.0 parts by weight or less, more preferably 0.05 parts by weight or more and 3.6 parts by weight or less, based on 100 parts by weight of the raw material monomer.

[0040] As the chain transfer agent, a chain transfer agent having an S atom is preferably used, and examples thereof include 3-mercapto-1,2-propanediol, 3-mercapto-1-propanol, 3-mercapto-2-butanol, 8-mercapto-1-octanol, 2-mercaptobenzimidazole, mercaptosuccinic acid, mercaptoacetic acid, etc. Of these, 3-mercapto-1,2-propanediol and mercaptosuccinic acid are preferably used.

[0041] The amount of the chain transfer agent added is preferably 0.1 parts by weight or more and 10.0 parts by weight or less, more preferably 0.4 parts by weight or more and 5.0 parts by weight or less, based on 100 parts by weight of the raw material monomer.

[0042] The temperature during polymerization is preferably 50°C or higher and 90°C or lower, more preferably 60°C or higher and more preferably 80°C or lower.

[0043] A vehicle composition can be prepared using the (meth)acrylic resin particles and a solvent containing an organic solvent. The vehicle composition containing the (meth)acrylic resin particles and a solvent containing an organic solvent also constitutes one aspect of the present invention.

[0044] The content of the (meth)acrylic resin particles in the vehicle composition is preferably 5% by weight or more and 30% by weight or less, more preferably 10% by weight or more and 20% by weight or less.

[0045] The vehicle composition contains an organic solvent. Examples of the organic solvent include alcohols such as aliphatic alcohols, glycols, terpene alcohols, and aromatic alcohols, aromatic hydrocarbons, esters, ketones, and N-methylpyrrolidone. Examples of the aliphatic alcohols include ethanol, propanol, isopropanol, heptanol, octanol, decanol, tridecanol, lauryl alcohol, tetradecyl alcohol, cetyl alcohol, 2-ethyl-1-hexanol, octadecyl alcohol, hexadecenol, oleyl alcohol, Texanol, 2-butyl-2-ethyl-1,3-propanediol, and neopentyl glycol. Examples of the glycols include ethylene glycol monobutyl ether, diethylene glycol monoethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoisobutyl ether, butyl carbitol, ethylene glycol monoethyl ether acetate, trimethylpentanediol monoisobutyrate, butyl carbitol acetate, Texanol, ethylene glycol monophenyl ether, propylene glycol monophenyl ether, and ethylene glycol ethyl ether. Examples of the terpene alcohols include terpineol, dihydroterpineol, terpineol acetate, and dihydroterpineol acetate. Examples of the aromatic alcohols include benzyl alcohol. Examples of the aromatic hydrocarbons include toluene. Examples of the esters include ethyl acetate, butyl acetate, hexyl acetate, isoamyl acetate, butyl butyrate, butyl lactate, dioctyl phthalate, and dioctyl adipate. Examples of the ketones include methyl isobutyl ketone, methyl ethyl ketone, methyl isobutyl ketone, and isophorone. Of these, aliphatic alcohols and terpene alcohols are preferred, and 2-butyl-2-ethyl-1,3-propanediol and dihydroterpineol acetate are more preferred.

[0046] The organic solvent preferably contains a compound having two or more OH groups. The content of the compound having two or more OH groups in the solvent is preferably 10% by weight or more and preferably 50% by weight or less. By setting the content within this range, there is an advantage that the dispersion of inorganic particles can be particularly excellent.

[0047] The content of the solvent in the vehicle composition is not particularly limited, but is preferably 65% ​​by weight or more and 90% by weight or less, more preferably 70% by weight or more and 85% by weight or less.

[0048] In the vehicle composition, the solvent preferably further contains water. The water content in the solvent is preferably 100 ppm by weight or more and preferably 40,000 ppm by weight or less. By containing water in the above range, there is an advantage that compatibility with the dispersant improves and thermal decomposition properties are improved. The water content in the solvent is more preferably 300 ppm by weight or more and more preferably 20,000 ppm by weight or less.

[0049] The weight concentration of S atoms contained in the vehicle composition is preferably 0.004 wt % or more, preferably 0.400 wt % or less, more preferably 0.100 wt % or more, and more preferably 0.200 wt % or less. The weight concentration of S atoms means the ratio of the weight of S atoms contained in the vehicle composition to the total weight of the vehicle composition, and can be calculated based on the following formula: Weight concentration of S atoms contained in vehicle composition = [Content (wt %) of (meth)acrylic resin particles in vehicle composition × Weight concentration of S atoms contained in (meth)acrylic resin particles (wt %)] ÷ 100

[0050] The weight concentration of COOH groups contained in the vehicle composition is preferably 0.005 wt% or more, preferably 0.500 wt% or less, more preferably 0.009 wt% or more, and more preferably 0.300 wt% or less. The weight concentration of COOH groups means the ratio of the weight of COOH groups contained in the vehicle composition to the total weight of the vehicle composition, and can be calculated based on the following formula: Weight concentration of COOH groups contained in vehicle composition = {[Content (wt%) of (meth)acrylic resin particles in vehicle composition x Weight concentration of COOH groups contained in (meth)acrylic resin particles (wt%)] + [Content (wt%) of organic solvent in vehicle composition x Weight concentration of COOH groups contained in organic solvent (wt%)]} / 100

[0051] The weight concentration of OH groups contained in the vehicle composition is preferably 0.01 wt % or more, preferably 13.00 wt % or less, more preferably 0.02 wt % or more, and more preferably 11.00 wt % or less. The weight concentration of OH groups means the ratio of the weight of OH groups contained in the vehicle composition to the total weight of the vehicle composition, and can be calculated based on the following formula: Weight concentration of OH groups contained in vehicle composition = {[Content (wt %) of (meth)acrylic resin particles in vehicle composition x Weight concentration of OH groups contained in (meth)acrylic resin particles (wt %)] + [Content (wt %) of organic solvent in vehicle composition x Weight concentration of OH groups contained in organic solvent (wt %)] + [Content (wt %) of water in vehicle composition x Weight concentration of OH groups in water (wt %)]} / 100

[0052] The weight concentration of K atoms contained in the vehicle composition is preferably 0.001 wt % or more, preferably 0.200 wt % or less, more preferably 0.010 wt % or more, and more preferably 0.160 wt % or less. The weight concentration of K atoms means the ratio of the weight of K atoms contained in the vehicle composition to the total weight of the vehicle composition, and can be calculated based on the following formula: Weight concentration of K atoms contained in vehicle composition = [Content (wt %) of (meth)acrylic resin particles in vehicle composition × Weight concentration of K atoms contained in (meth)acrylic resin particles (wt %)] ÷ 100

[0053] Furthermore, the ratio of the weight concentration of OH groups to the weight concentration of S atoms contained in the vehicle composition (weight concentration of OH groups / weight concentration of S atoms) is preferably 0.1 or more and 100 or less, more preferably 0.2 or more and 75 or less.

[0054] The vehicle composition may be produced, for example, by adding an organic solvent, water, etc. to the (meth)acrylic resin particles obtained by the above method and stirring and mixing them.

[0055] A slurry composition can be prepared using the vehicle composition, inorganic particles, and dispersant. A slurry composition containing the vehicle composition, inorganic particles, and dispersant also constitutes one aspect of the present invention.

[0056] The content of the (meth)acrylic resin particles in the slurry composition is preferably 3% by weight or more and 10% by weight or less, more preferably 5% by weight or more and 8% by weight or less.

[0057] The content of the organic solvent in the slurry composition is preferably 25% by weight or more and 40% by weight or less, more preferably 30% by weight or more and 35% by weight or less.

[0058] The water content in the slurry composition is preferably 30 ppm by weight or more, and preferably 15,000 ppm by weight or less, more preferably 1,000 ppm by weight or more, more preferably 10,000 ppm by weight or less, even more preferably 5,000 ppm by weight or more, and even more preferably 7,000 ppm by weight or less.

[0059] The slurry composition contains inorganic particles, and the inorganic particles are not particularly limited, and examples thereof include glass powder, ceramic powder, fluorescent fine particles, silicon oxide, metal fine particles, and the like.

[0060] The glass powder is not particularly limited, and examples thereof include glass powders such as bismuth oxide glass, silicate glass, lead glass, zinc glass, and boron glass, and CaO—Al ２ O ３ -SiO ２ system, MgO-Al ２ O３ -SiO ２ system, LiO ２ -Al ２ O ３ -SiO ２ Examples of the glass powder include glass powders of various silicon oxides such as SnO—B ２ O ３ -P ２ O ５ -Al ２ O ３ mixture, PbO-B ２ O ３ -SiO ２ Mixture, BaO-ZnO-B ２ O ３ -SiO ２ Mixture, ZnO-Bi ２ O ３ -B ２ O ３ -SiO ２ mixture, Bi ２ O ３ -B ２ O ３ -BaO-CuO mixture, Bi ２ O ３ -ZnO-B ２ O ３ -Al ２ O ３ -SrO mixture, ZnO-Bi ２ O ３ -B ２ O ３ mixture, Bi ２ O ３ -SiO ２ mixture, P ２ O ５ -Na ２ O-CaO-BaO-Al ２ O ３ -B ２ O ３ mixture, P ２ O ５ -SnO mixture, P ２ O ５ -SnO-B ２ O ３ mixture, P ２ O ５ -SnO-SiO ２ mixture, CuO-P ２ O５ -RO mixture, SiO ２ -B ２ O ３ -ZnO-Na ２ O-Li ２ O-NaF-V ２ O ５ mixture, P ２ O ５ -ZnO-SnO-R ２ O-RO mixture, B ２ O ３ -SiO ２ -ZnO mixture, B ２ O ３ -SiO ２ -Al ２ O ３ -ZrO ２ mixture, SiO ２ -B ２ O ３ -ZnO-R ２ O-RO mixture, SiO ２ -B ２ O ３ -Al ２ O ３ -RO-R ２ O mixture, SrO-ZnO-P ２ O ５ Mixture, SrO-ZnO-P ２ O ５ Mixture, BaO-ZnO-B ２ O ３ -SiO ２ Glass powders such as mixtures can also be used. R is an element selected from the group consisting of Zn, Ba, Ca, Mg, Sr, Sn, Ni, Fe, and Mn. In particular, PbO—B ２ O ３ -SiO ２ Mixture glass powder and lead-free BaO-ZnO-B ２ O ３ -SiO ２ Mixture or ZnO-Bi ２ O ３ -B ２ O ３ -SiO ２ Lead-free glass powders such as mixtures are preferred.

[0061] The ceramic powder is not particularly limited, and examples thereof include alumina, ferrite, zirconia, zircon, barium zirconate, calcium zirconate, titanium oxide, barium titanate, strontium titanate, calcium titanate, magnesium titanate, zinc titanate, lanthanum titanate, neodymium titanate, lead zirconate titanate, alumina nitride, silicon nitride, boron nitride, boron carbide, barium stannate, calcium stannate, magnesium silicate, mullite, steatite, cordierite, and forsterite. ITO, FTO, niobium oxide, vanadium oxide, tungsten oxide, lanthanum strontium manganite, lanthanum strontium cobalt ferrite, yttrium-stabilized zirconia, gadolinium-doped ceria, nickel oxide, and lanthanum chromite can also be used. The phosphor fine particles are not particularly limited, and examples of the phosphor material include blue, red, and green phosphor materials conventionally known as phosphor materials for displays. The blue phosphor material is, for example, MgAl １０ O １７ : Eu-based, Y ２ SiO ５ : Ce-based, CaWO ４ : Pb-based, BaMgAl １４ O ２３ :Eu-based, BaMgAl １６ O ２７ : Eu-based, BaMg ２ Al １４ O ２３ : Eu-based, BaMg ２ Al １４ O ２７ :Eu-based and ZnS:(Ag,Cd)-based materials are used. ２ O ３ : Eu-based, Y ２ SiO ５ : Eu-based, Y ３ Al ５ O １２ : Eu-based, Zn ３ (P.O. ４ ) ２ : Mn-based, YBO ３ :Eu-based, (Y,Gd)BO ３ : Eu-based, GdBO３ : Eu-based, ScBO ３ : Eu-based, LuBO ３ : Eu-based materials are used. As the green phosphor material, for example, Zn ２ SiO ４ : Mn-based, BaAl １２ O １９ :Mn-based, SrAl １３ O １９ : Mn-based, CaAl １２ O １９ : Mn-based, YBO ３ :Tb series, BaMgAl １４ O ２３ : Mn-based, LuBO ３ :Tb series, GdBO ３ :Tb series, ScBO ３ :Tb series, Sr6Si ３ O ３ Cl ４ Other examples include ZnO:Zn, ZnS:(Cu,Al), ZnS:Ag, Y ２ O ２ S: Eu-based, ZnS: Zn-based, (Y, Cd)BO ３ :Eu-based, BaMgAl １２ O ２３ : Eu-based materials can also be used.

[0062] The metal particles are not particularly limited, and examples thereof include powders of iron, copper, nickel, palladium, platinum, gold, silver, aluminum, tungsten, and alloys thereof. Metals such as copper and iron, which have good adsorption properties with carboxyl groups, amino groups, amide groups, and the like and are easily oxidized, can also be suitably used. These metal powders may be used alone or in combination of two or more. In addition to metal complexes, various carbon blacks, carbon nanotubes, and the like may also be used as the metal particles.

[0063] The inorganic particles preferably contain lithium or titanium. Specifically, for example, LiO ２ ・Al ２ O ３ SiO ２ low-melting-point glass such as inorganic glass, Li ２ S-M ｘ Sｙ Lithium sulfur-based glass such as (M=B, Si, Ge, P), LiCeO ２ Lithium cobalt composite oxides such as LiMnO ４ Lithium manganese composite oxide, lithium nickel composite oxide, lithium vanadium composite oxide, lithium zirconium composite oxide, lithium hafnium composite oxide, lithium silicophosphate (Li ３．５ Si ０．５ P ０．５ O ４ ), lithium titanium phosphate (LiTi ２ (P.O. ４ ) ３ ), lithium titanate (Li ４ Ti ５ O １２ ), Li ４／３ Ti ５／３ O ４ , LiCoO ２ , lithium germanium phosphate (LiGe ２ (P.O. ４ ) ３ ), Li ２ -SiS-based glass, Li ４ GeS ４ -Li ３ P.S. ４ LiSiO based glass ３ , LiMn ２ O ４ , Li ２ S-P ２ S ５ Glass and ceramics, Li ２ O—SiO ２ , Li ２ O-V ２ O ５ -SiO ２ , LiS-SiS ２ -Li ４ SiO ４ based glass, ion-conductive oxides such as LiPON, Li ２ O-P ２ O ５ -B ２ O ３ , Li ２ O-GeO ２ Lithium oxide compounds such as Ba, Li ｘ Al ｙ Tiｚ (P.O. ４ ) ３ La-based glass ｘ Li ｙ TiO ｚ Li-based glass ｘ Ge ｙ P ｚ O ４ Li-based glass ７ La ３ Zr ２ O １２ Li-based glass ｖ Si ｗ P ｘ S ｙ Cl ｚ LiNbO ３ Lithium niobium oxides such as Li-β-alumina, lithium alumina compounds such as Li １４ Zn(GeO ４ ) ４ Lithium zinc oxides such as those mentioned above are also included.

[0064] The inorganic particles have an average particle size of preferably 0.01 μm or more and 5 μm or less, more preferably 0.05 μm or more and 3 μm or less, still more preferably 0.1 μm or more and still more preferably 1 μm or less. The average particle size can be determined, for example, by measuring the volume average particle size using a laser diffraction / scattering particle size distribution analyzer.

[0065] The content of the inorganic particles in the slurry composition is preferably 30% by weight or more and 90% by weight or less. Within this range, the slurry composition has sufficient viscosity, excellent coating properties, and excellent dispersibility of the inorganic particles. The content of the inorganic particles is more preferably 40% by weight or more and 70% by weight or less.

[0066] The slurry composition contains a dispersant. Suitable examples of the dispersant include fatty acids, aliphatic amines, alkanolamides, and phosphate esters. A silane coupling agent may also be added. The fatty acids are not particularly limited, and examples include saturated fatty acids such as behenic acid, stearic acid, palmitic acid, myristic acid, lauric acid, capric acid, caprylic acid, and coconut fatty acid; and unsaturated fatty acids such as oleic acid, linoleic acid, linolenic acid, sorbic acid, tallow fatty acid, and hardened castor fatty acid. Among these, lauric acid, stearic acid, and oleic acid are preferred. The aliphatic amines are not particularly limited, and examples include laurylamine, myristylamine, cetylamine, stearylamine, oleylamine, alkyl (coconut) amines, alkyl (hardened tallow) amines, alkyl (beef tallow) amines, and alkyl (soybean) amines. The alkanolamide is not particularly limited, and examples thereof include coconut fatty acid diethanolamide, beef tallow fatty acid diethanolamide, lauric acid diethanolamide, oleic acid diethanolamide, etc. The phosphate ester is not particularly limited, and examples thereof include polyoxyethylene alkyl ether phosphate ester, polyoxyethylene alkyl allyl ether phosphate ester.

[0067] The content of the dispersant in the slurry composition is preferably 0.1% by weight or more and 1% by weight or less, more preferably 0.15% by weight or more and 0.5% by weight or less.

[0068] The slurry composition may further contain additives such as a plasticizer, a surfactant, etc. Examples of the plasticizer include di(butoxyethyl adipate), dibutoxyethoxyethyl adipate, triethylene glycol dibutyl, triethylene glycol bis(2-ethylhexanoate), triethylene glycol dihexanoate, triethyl acetylcitrate, tributyl acetylcitrate, diethyl acetylcitrate, dibutyl acetylcitrate, dibutyl sebacate, triacetin, diethyl acetyloxymalonate, and diethyl ethoxymalonate.

[0069] The surfactant is not particularly limited, and examples thereof include cationic surfactants, anionic surfactants, and nonionic surfactants. The nonionic surfactant is not particularly limited, but is preferably a nonionic surfactant with an HLB value of 10 to 20. Here, the HLB value is used as an index representing the hydrophilicity and lipophilicity of a surfactant, and several calculation methods have been proposed. For example, for an ester-based surfactant, the saponification value is S, the acid value of the fatty acid constituting the surfactant is A, and the HLB value is defined as 20 (1-S / A). Specifically, nonionic surfactants having polyethylene oxide with an alkylene ether attached to the fatty chain are suitable, and specific examples of suitable surfactants include polyoxyethylene lauryl ether and polyoxyethylene cetyl ether. Although the nonionic surfactant has good thermal decomposition properties, adding a large amount may reduce the thermal decomposition properties of the inorganic particle dispersion slurry composition. Therefore, the preferred upper limit of the content is 5 wt%.

[0070] The viscosity of the slurry composition of the present invention is not particularly limited, but the viscosity measured at 25°C using a Brookfield viscometer is preferably 80,000 or more, preferably 2,000,000 or less, more preferably 100,000 or more, and more preferably 600,000 or less. By setting the viscosity within the above range, it becomes possible for the obtained inorganic particle-dispersed sheet to maintain a predetermined shape after coating by a die coating printing method or the like. Furthermore, defects such as indelible die coating marks can be prevented, and excellent printability can be achieved.

[0071] The method for preparing the slurry composition is not particularly limited, and examples thereof include conventionally known stirring methods, specifically, for example, a method in which the vehicle composition, the inorganic particles, the dispersant, and other components added as needed, such as an additional solvent and a plasticizer, are stirred using a triple roll, etc. The order of addition of the components of the slurry composition can be appropriately determined.

[0072] Electronic components can be produced using the above-mentioned slurry composition. A method for producing an electronic component using the above-mentioned slurry composition also constitutes one aspect of the present invention. Examples of the electronic component include die attach paste (ACP), die attach film (ACF), TSV, TGV via electrodes, touch panels, various circuits for RFID and sensor substrates, various die bonding agents, sealants for MEMS devices, solar cells, laminated ceramic capacitors, LTCC, silicon capacitors, and electrode materials for all-solid-state batteries. In addition to the above-mentioned electrode circuit applications, the composition can also be used for antibacterial materials, electromagnetic wave shielding, catalysts, fluorescent materials, and the like.

[0073] For example, the slurry composition may be applied to a support film having one side subjected to a release treatment, the organic solvent may be dried, and the resulting product may be molded to produce an inorganic particle-dispersed molded product. The shape of the inorganic particle-dispersed molded product is not particularly limited, and may be, for example, a sheet.

[0074] Examples of methods for producing the inorganic particle-dispersed molded product include a method in which the slurry composition is applied to a support film by a coating method such as a roll coater, die coater, squeeze coater, or curtain coater to form a uniform coating film.

[0075] For example, when the inorganic particle-dispersed molded product is in the form of a sheet, the support film used in producing the inorganic particle-dispersed molded product is preferably a resin film that is heat-resistant, solvent-resistant, and flexible. The flexibility of the support film allows the inorganic particle-dispersed slurry composition to be applied to the surface of the support film using a roll coater, blade coater, or the like, and the resulting inorganic particle-dispersed sheet-forming film can be stored and supplied in a rolled state.

[0076] Examples of resins that can form the support film include polyethylene terephthalate, polyester, polyethylene, polypropylene, polystyrene, polyimide, polyvinyl alcohol, polyvinyl chloride, fluorine-containing resins such as polyfluoroethylene, nylon, cellulose, etc. The thickness of the support film is preferably, for example, 20 to 100 μm. In addition, the surface of the support film is preferably subjected to a release treatment, which allows the support film to be easily peeled off in the transfer step.

[0077] The slurry composition can be applied and dried to produce an inorganic particle dispersion molded product. Furthermore, the slurry composition and the inorganic particle dispersion molded product can be used in a conductive paste for external electrodes to produce a multilayer ceramic capacitor, which is an electronic component.

[0078] A method for producing the above-mentioned laminated ceramic capacitor includes a manufacturing method including a step of printing a conductive paste on the above-mentioned inorganic particle dispersion molding and drying it to prepare a dielectric sheet, and a step of laminating the dielectric sheets.

[0079] The conductive paste contains a conductive powder. The material of the conductive powder is not particularly limited as long as it is a conductive material, and examples thereof include nickel, palladium, platinum, gold, silver, copper, molybdenum, tin, and alloys thereof. These conductive powders may be used alone or in combination of two or more.

[0080] The method for printing the conductive paste is not particularly limited, and examples thereof include screen printing, die coating printing, offset printing, gravure printing, and inkjet printing.

[0081] In the method for manufacturing the laminated ceramic capacitor, dielectric sheets on which the conductive paste is printed are stacked to produce a raw ceramic laminate, which is then fired in a reducing atmosphere at a temperature of 1000 to 1500°C, thereby obtaining a large number of component elements.

[0082] Next, a conductive paste for external electrodes containing the above-mentioned (meth)acrylic resin particles is applied to both end surfaces of each of these component elements by a dipping method, and then the applied paste is dried at 100 to 200°C and then fired at 450 to 800°C in a reducing atmosphere to form external electrodes on both end surfaces of the component elements.

[0083] Next, the external electrodes are electrolytically plated to form a Cu film, a Ni film, and a Sn film in this order on the external electrodes, thereby obtaining a laminated ceramic capacitor.

[0084] According to the present invention, (meth)acrylic resin particles are provided that have excellent low-temperature decomposition properties, and when used as a binder for inorganic particle dispersion, can prevent deterioration due to oxidation of inorganic particles such as copper, and can be used to prepare an inorganic particle-dispersed slurry composition that is particularly excellent in dispersibility of fine inorganic particles. Furthermore, (meth)acrylic resin particles can be provided that, when used as a binder for the external electrodes of a multilayer ceramic capacitor, can produce a multilayer ceramic capacitor with excellent reliability. Furthermore, vehicle compositions, slurry compositions, and methods for producing electronic components can be provided.

[0085] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.

[0086] (Examples 1 to 21, Comparative Examples 1 to 4) (Preparation of (meth)acrylic resin particles) A ​​2L separable flask equipped with a stirrer, a cooler, a thermometer, a hot water bath, and a nitrogen gas inlet was prepared, and a total of 100 parts by weight of monomers was charged into the 2L separable flask so as to obtain the formulation shown in Tables 1 and 2. Furthermore, 50 parts by weight of butyl acetate was mixed as an organic solvent to obtain a monomer mixture. The following monomers were used. MMA: methyl methacrylate EMA: ethyl methacrylate iBMA: isobutyl methacrylate 2EHMA: 2-ethylhexyl methacrylate

[0087] The resulting monomer mixture was bubbled with nitrogen gas for 20 minutes to remove dissolved oxygen, and then the atmosphere in the separable flask was replaced with nitrogen gas. The temperature of the water bath was raised to 80°C while stirring. Subsequently, a chain transfer agent and a polymerization initiator were added in the amounts shown in Tables 1 and 2 to initiate polymerization. Seven hours after the start of polymerization, the mixture was cooled to room temperature to terminate the polymerization. The resulting resin solution was then dried in an oven at 130°C to remove the organic solvent. This yielded (meth)acrylic resin particles. The following chain transfer agents and polymerization initiators were used. <Chain transfer agent> CT-1: 3-mercapto-1,2-propanediol CT-2: mercaptosuccinic acid <Polymerization initiator> KPS: potassium persulfate (manufactured by FUJIFILM Wako Pure Chemical Industries, Ltd.) VA-086: 2,2'-azobis[2-methyl-N-(2-hydroxyethyl)propionamide] (manufactured by FUJIFILM Wako Pure Chemical Industries, Ltd.)

[0088] (Preparation of vehicle composition for dispersing inorganic particles) 85 parts by weight of a solvent having the formulation shown in Tables 3 and 4 was added to 15 parts by weight of the obtained (meth)acrylic resin particles and stirred until homogeneous to obtain a vehicle composition for dispersing inorganic particles. The following solvents were used: DHTA: dihydroterpineol acetate BEPG: 2-butyl-2-ethyl-1,3-propanediol

[0089] (Preparation of inorganic particle dispersion slurry composition) A dispersant and inorganic particles were added to the obtained vehicle composition for dispersing inorganic particles in the formulations shown in Tables 3 and 4, and the mixture was kneaded with a high-speed stirrer to obtain an inorganic particle dispersion slurry composition. The following dispersants and inorganic particles were used. <Dispersant> Nopcospers 092 (manufactured by Sanyo Chemical Industries, Ltd.) <Inorganic particles> Copper powder (manufactured by Fujino Metals Co., Ltd., average particle size 0.1 μm) Glass frit (manufactured by AGC, product name ASF-1094, main component Bi) ２ O ３・ B ２ O ３・ SiO ２ , average particle size 0.8 μm)

[0090] (Fabrication of Multilayer Ceramic Capacitors) First, a perovskite oxide containing Ba and Ti was used as the dielectric material for the inner and outer ceramic layers. 80 parts by weight of the above ceramic dielectric powder was mixed with 8 parts by weight of an acrylic binder, 10 parts by weight of an organic solvent, 1 part by weight of a plasticizer, and 1 part by weight of a dispersant to prepare a ceramic slurry. This ceramic slurry was then applied to a resin film to a thickness of 3.0 μm after drying to prepare ceramic green sheets for the inner and outer layers. The acrylic binder used was Marproof MH-03041 (manufactured by NOF Corporation), the organic solvent was butyl acetate, the plasticizer was G-260 (manufactured by Sekisui Chemical Co., Ltd.), and the dispersant was Nopcosperse 092 (manufactured by Sanyo Chemical Industries, Ltd.).

[0091] Next, a conductive paste was screen-printed onto the inner layer ceramic green sheet in a pattern corresponding to the size (3.2 mm x 1.6 mm) of the fired ceramic element, resulting in a dry thickness of 1±0.1 μm. The conductive paste was prepared by blending 50 parts by weight of Ni powder, 5 parts by weight of a perovskite oxide containing Ba and Ti as co-materials, 44 parts by weight of the inorganic particle dispersion vehicle composition, and 1 part by weight of a polycarboxylic acid-based dispersant. The binder resin was blended to a ratio of 6.6 parts by weight to 50 parts by weight of Ni, and the conductive paste was obtained using a ball mill. The Ni powder used had an average particle size of 0.2 μm. The perovskite oxide containing Ba and Ti had an average particle size of 30 nm.

[0092] Then, after peeling off the ceramic green sheets for the inner layer and the ceramic green sheets for the outer layer on which the conductive paste was screen-printed from the resin film, a total of 350 sheets were stacked and pressed together to form a laminate, which was then cut into a predetermined size and divided into individual unfired ceramic bodies. Each ceramic body was degreased in a nitrogen atmosphere at 400°C for 10 hours, and then heated in a nitrogen-hydrogen-water vapor mixed atmosphere at a top temperature of 1200°C and an oxygen partial pressure of 10 －９ ~10 －１０The ceramic bodies were fired under conditions of 1000 MPa and 1000 psi. Next, the inorganic particle dispersion slurry compositions obtained in each of the Examples and Comparative Examples were applied to the fired ceramic bodies by dipping so that the side thickness after drying was 50 μm, and then dried. Subsequently, electrode layers were formed in a nitrogen-air-water vapor mixed atmosphere or a nitrogen-hydrogen-water vapor mixed atmosphere at a top temperature of 790 to 880°C, with an oxygen electromotive force at the top temperature of 220 to 280 mV. A first plating layer containing Ni was then formed on the surface of the electrode layer, and a second plating layer containing Sn was formed on the surface of the first plating layer, thereby forming external electrodes with a three-layer structure, and a multilayer ceramic capacitor was fabricated.

[0093] Comparative Examples 5 and 6 An inorganic particle dispersion vehicle composition, an inorganic particle dispersion slurry composition, and a laminated ceramic capacitor were obtained in the same manner as in Example 1, except that a polyvinyl butyral resin (manufactured by Sekisui Chemical Co., Ltd., BH-3) and an ethyl cellulose resin (manufactured by Nisshin Chemical Co., Ltd., STD-100) were used instead of the (meth)acrylic resin particles.

[0094] <Evaluation> The (meth)acrylic resin particle and inorganic particle dispersion slurry compositions obtained in the examples and comparative examples were evaluated as follows. The results are shown in Tables 1 to 4.

[0095] (1) Weight Concentration of S Atoms, Weight Concentration of OH Groups, Weight Concentration of COOH Groups, and Weight Concentration of K Atoms The weight concentrations of S atoms, OH groups, COOH groups, and K atoms contained in the (meth)acrylic resin particles were calculated by the following method. Weight concentration of S atoms contained in (meth)acrylic resin particles=[(weight of S atoms contained in all monomers+weight of S atoms contained in all chain transfer agents+weight of S atoms contained in all polymerization initiators) / (weight of all monomers+weight of all chain transfer agents+weight of all polymerization initiators)]×100 Weight concentration of OH groups contained in (meth)acrylic resin particles=[(weight of OH groups contained in all monomers+weight of OH groups contained in all chain transfer agents+weight of OH groups contained in all polymerization initiators) / (weight of all monomers+weight of all chain transfer agents+weight of all polymerization initiators)]×100 Weight concentration of COOH groups contained in (meth)acrylic resin particles=[(weight of COOH groups contained in all monomers+weight of COOH groups contained in all chain transfer agents+weight of COOH groups contained in all polymerization initiators) / (weight of all monomers+weight of all chain transfer agents+weight of all polymerization initiators)]×100 Weight concentration of K atoms contained in (meth)acrylic resin particles=[(weight of K atoms contained in all monomers+weight of K atoms contained in all chain transfer agents+weight of K atoms contained in all polymerization initiators) / (weight of all monomers+weight of all chain transfer agents+weight of all polymerization initiators)]×100

[0096] (2) Particle size The obtained vehicle composition for dispersing inorganic particles was fed to a laser diffraction / scattering particle size distribution measuring device (LA-950, manufactured by Horiba, Ltd.) to measure the volume average particle size of the (meth)acrylic resin particles.

[0097] (3) Average Molecular Weight The weight average molecular weight (Mw) and number average molecular weight (Mn) of the obtained (meth)acrylic resin particles were measured in terms of polystyrene by gel permeation chromatography using an LF-804 column (manufactured by SHOKO Corporation), and the molecular weight distribution (Mw / Mn) was calculated.

[0098] (4) Viscosity The viscosity of the obtained inorganic particle dispersion slurry composition at 25° C. was measured using a Brookfield type viscometer (DVII+Pro, manufactured by Brookfield Corporation).

[0099] (5) Storage Stability The obtained inorganic particle dispersion slurry composition was stored in an environment at a temperature of 23°C and a humidity of 50%. After one month, the state of the slurry composition was checked and evaluated according to the following criteria. High storage stability indicates excellent dispersibility of the inorganic particles. ◯: Separation of the slurry composition and sedimentation of the inorganic particles were not observed, and the slurry composition remained smooth. Δ: Sedimentation of the inorganic particles was not observed, but separation of the slurry composition was observed. ×: Sedimentation of the inorganic particles occurred, or the slurry composition gelled.

[0100] (6) Viscosity Stability The viscosity of the obtained inorganic particle-dispersed slurry composition at 20°C was taken as the initial viscosity measured in the same manner as in "(4) Viscosity". In addition, the slurry composition after measurement was stored in a thermostatic chamber at 20°C for one month, and the viscosity after storage was measured in the same manner. The rate of change in viscosity after storage relative to the initial viscosity ([(viscosity after storage - initial viscosity) / initial viscosity] x 100) was determined and evaluated according to the following criteria. High viscosity stability can be said to indicate excellent dispersibility of inorganic particles. ◎: The rate of change in viscosity was less than 5%. ○: The rate of change in viscosity was 5% or more but less than 10%. △: The rate of change in viscosity was 10% or more but less than 20%. ×: The rate of change in viscosity was 20% or more.

[0101] (7) Printability Using a screen printer (MT-320TV manufactured by Microtec), a screen plate (ST500 manufactured by Tokyo Process Services, 2 μm emulsion, 2012 pattern, screen frame 320 mm × 320 mm), and a printed glass substrate (soda glass, 150 mm × 150 mm, 1.5 mm thick), an inorganic particle dispersion slurry composition was printed under an environment of 23°C and 50% humidity, and the solvent was dried in a fan oven at 100°C for 30 minutes. The printed pattern was observed visually or with a magnifying microscope to confirm the shape of the edge of the printed surface and evaluated according to the following criteria: ⊚: The print pattern was printed according to the pattern, and no thread-like irregularities were observed at the print edge. ◯: The print pattern was printed according to the pattern, and one thread-like irregularity was observed at the print edge. Δ: The print pattern was printed according to the pattern, and 2 to 4 thread-like irregularities were observed at the print edge. ×: The print pattern was not printed according to the pattern, or five or more thread-like irregularities were observed at the print edge.

[0102] (8) Decomposability The obtained inorganic particle dispersion slurry composition was packed into a platinum pan of a TG-DTA, and the temperature was raised from 30°C at a rate of 5°C / min in a nitrogen atmosphere to evaporate the solvent and thermally decompose the resin and dispersant. Thereafter, the time (minutes) until the decomposition rate reached 61.9 wt% (when 90 wt% degreasing was completed) was measured.

[0103] (9) Oxidation State The obtained inorganic particle dispersion slurry composition was packed into a platinum pan of a TG-DTA, and the temperature was raised from 30°C at 5°C / min in a nitrogen atmosphere to evaporate the solvent and thermally decompose the resin and dispersant. The time (minutes) until 61.9 wt% was reached (90 wt% degreasing was completed) was then measured. The color of the contents of the platinum pan remaining after the measurement was visually evaluated according to the following criteria: ∘: The color of the contents had not changed from the color of the copper used to prepare the inorganic particle dispersion slurry composition. ×: The color of the contents had changed from the color of the copper used to prepare the inorganic particle dispersion slurry composition.

[0104] (10) Voltage Defect Rate The voltage defect rate was calculated by measuring the presence or absence of short-circuit defects when a DC voltage of 150 V was applied to 10,000 of the obtained multilayer ceramic capacitors, and then calculating the voltage defect rate using the following formula: Voltage Defect Rate = Number of Short-Circuited Samples / 10,000

[0105] (11) Incidence Rate of Products with Decreased Capacitance The incidence rate of products with decreased capacitance was calculated by measuring the capacitance of 10,000 of the obtained multilayer ceramic capacitors, and judging samples with a capacitance of less than 90% of the design capacitance as products with decreased capacitance.

[0106]

[0107]

[0108]

[0109]

[0110] According to the present invention, (meth)acrylic resin particles are provided that have excellent low-temperature decomposition properties, and when used as a binder for inorganic particle dispersion, can prevent deterioration due to oxidation of inorganic particles such as copper, and can be used to prepare an inorganic particle-dispersed slurry composition that is particularly excellent in dispersibility of fine inorganic particles. Furthermore, (meth)acrylic resin particles can be provided that, when used as a binder for the external electrodes of a multilayer ceramic capacitor, can produce a multilayer ceramic capacitor with excellent reliability. Furthermore, vehicle compositions, slurry compositions, and methods for producing electronic components can be provided.

Claims

1. The weight average molecular weight is 100,000 or more and 1,000,000 or less, (Meth)acrylic resin particles, having a weight concentration of S atoms of 0.03% by weight or more and 2.50% by weight or less.

2. The (meth)acrylic resin particles according to claim 1 , wherein the weight concentration of COOH groups is from 0.06% by weight to 3.00% by weight.

3. The (meth)acrylic resin particles according to claim 1 or 2, wherein the weight concentration of K atoms is 0.010% by weight or more and 1.000% by weight or less.

4. The (meth)acrylic resin particles according to claim 1 or 2, wherein the content of components derived from acrylic monomers is 5% by weight or less.

5. The (meth)acrylic resin particles according to claim 1 or 2, having an average particle size of 0.1 μm or more and 1.0 μm or less.

6. A vehicle composition comprising the (meth)acrylic resin particles according to claim 1 or 2 and a solvent containing an organic solvent.

7. 7. The vehicle composition according to claim 6, wherein the solvent further contains water in an amount of 100 ppm by weight or more and 40,000 ppm by weight or less.

8. The organic solvent contains a compound having two or more OH groups, 7. The vehicle composition according to claim 6, wherein the content of the compound having two or more OH groups in the solvent is from 10% by weight to 50% by weight.

9. A slurry composition comprising the vehicle composition according to claim 6, inorganic particles, and a dispersant.

10. A method for producing an electronic component, comprising using the slurry composition according to claim 9.