(Meth)acrylic resin, vehicle composition, slurry composition and electronic component

Abstract

To provide a (meth)acrylic resin capable of producing a ceramic laminate which can achieve both excellent low-temperature decomposability of a slurry composition and high strength of a ceramic green sheet and can be further thinned, and also to provide a vehicle composition, a slurry composition and an electronic component containing the (meth)acrylic resin.SOLUTION: There is provided a (meth)acrylic resin which has a constituent unit derived from a (meth) acrylic acid ester monomer, wherein the (meth)acrylic acid ester monomer includes a (meth)acrylic acid ester monomer A and a (meth)acrylic acid ester monomer B, and when the number of carbon atoms of an ester substituent possessed by the (meth)acrylic acid ester monomer A is defined as X, the number of carbon atoms of an ester substituent possessed by the (meth)acrylic acid ester monomer B is 4X.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a (meth)acrylic resin. [Background technology]

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

[0003] In recent years, there has been a demand for lower temperatures in the degreasing process, which removes binder resin, in order to reduce the energy required for firing ceramics. Furthermore, there is a growing demand for lighter, more powerful ceramic parts, which has led to a demand for thinner and more multi-layered ceramic green sheets during the manufacturing process.

[0004] Patent Document 1 describes the use of acrylic resin, polyvinyl butyral resin, polyvinyl acetal resin, ethyl cellulose resin, etc. as binder resins for such ceramic molding, and particularly describes the use of polyvinyl butyral resin or polyvinyl acetal resin to thin the sheet. Patent Document 2 describes a methacrylate copolymer obtained by copolymerizing isobutyl methacrylate, 2-ethylhexyl methacrylate, and a hydroxyl group-containing methacrylate in a predetermined ratio, and claims that the use of such a binder resin can provide good moldability and degreasing properties. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-84433 [Patent Document 2] Japanese Patent Application Publication No. 10-167836 Summary of the Invention [Problem to be solved by the invention]

[0006] To thin ceramic green sheets, binder resins must have sufficient strength, and increasing their strength generally requires increasing their molecular weight. However, increasing the molecular weight increases the viscosity of the slurry composition in which inorganic particles and binder are dispersed, resulting in poor dispersion of the inorganic particles, resulting in the formation of foreign matter in the ceramic green sheets and reduced strength. As described in Patent Document 1, polyvinyl butyral resins can be used to thin ceramic green sheets, but they have a high decomposition temperature and cannot be degreased at low temperatures. Furthermore, methacrylic acid ester copolymers, as described in Patent Document 2, can be degreased at low temperatures, but the resin itself is brittle and cannot be thinned. Therefore, there is a need for binder resins that can achieve both low degreasing temperatures and thinning.

[0007] The present invention aims to provide a (meth)acrylic resin that can produce ceramic laminates that can be further thinned by achieving both excellent low-temperature decomposition properties of a slurry composition and high strength of a ceramic green sheet, and also aims to provide a vehicle composition, a slurry composition, and an electronic component that contain the (meth)acrylic resin. [Means for solving the problem]

[0008] The present disclosure (1) is a (meth)acrylic resin having a structural unit derived from a (meth)acrylic acid ester monomer, the (meth)acrylic acid ester monomer including a (meth)acrylic acid ester monomer A and a (meth)acrylic acid ester monomer B, wherein when the number of carbon atoms of an ester substituent of the (meth)acrylic acid ester monomer A is X, the number of carbon atoms of an ester substituent of the (meth)acrylic acid ester monomer B is 4X. The present disclosure (2) is the (meth)acrylic resin of the present disclosure (1), in which the ratio of the content of the structural units derived from (meth)acrylic acid ester monomer B to the content of the structural units derived from (meth)acrylic acid ester monomer A (monomer B / monomer A) is 3 or more and 12 or less. The present disclosure (3) is the (meth)acrylic resin of the present disclosure (1) or (2), in which the (meth)acrylic acid ester monomer is a methacrylic acid ester monomer. The present disclosure (4) is a (meth)acrylic resin in any combination with any of the present disclosures (1) to (3), in which the Ti value of the resin solution dissolved in butyl acetate is 1.5 or more and 2.5 or less. The present disclosure (5) is a (meth)acrylic resin in any combination with any of the present disclosures (1) to (4), wherein the (meth)acrylic acid ester monomer includes a (meth)acrylic acid ester monomer having a branched chain ester substituent and a (meth)acrylic acid ester monomer having a linear chain ester substituent, the ester substituents having the same number of carbon atoms. The present disclosure (6) is a (meth)acrylic resin according to the present disclosure (5), in which the ratio of the content of structural units derived from (meth)acrylic ester monomers having branched-chain ester substituents to the content of structural units derived from (meth)acrylic ester monomers having straight-chain ester substituents, the ester substituents having the same number of carbon atoms, ((meth)acrylic ester monomers having branched-chain ester substituents / (meth)acrylic ester monomers having straight-chain ester substituents (the ester substituents have the same number of carbon atoms)) is 0.5 or more and 2.0 or less. The present disclosure (7) is a vehicle composition containing the (meth)acrylic resin of any one of the present disclosures (1) to (6) and an organic solvent. The present disclosure (8) is the vehicle composition of the present disclosure (7), further containing water, wherein the content of the water is 10 ppm by weight or more and 12,000 ppm by weight or less. The present disclosure (9) is a slurry composition containing the vehicle composition of the present disclosure (7), inorganic particles, and a dispersant. The present disclosure (10) is a slurry composition containing the vehicle composition of the present disclosure (8), inorganic particles, and a dispersant. The present disclosure (11) is an electronic component formed using the slurry composition of the present disclosure (9). The present disclosure (12) is an electronic component formed using the slurry composition of the present disclosure (10). The present invention will be described in detail below.

[0009] The present inventors have discovered that a slurry composition exhibiting excellent low-temperature decomposition properties can be obtained by combining multiple (meth)acrylic acid ester monomers such that, when the number of carbon atoms in the ester substituent of (meth)acrylic acid ester monomer A is X, the number of carbon atoms in the ester substituent of (meth)acrylic acid ester monomer B is 4X. Furthermore, they have discovered that when such a (meth)acrylic resin is used as a binder for dispersing inorganic particles, a ceramic green sheet with high strength can be obtained, enabling further thinning. They have also discovered that the use of such a (meth)acrylic resin enables the production of a ceramic laminate with excellent properties, leading to the completion of the present invention.

[0010] The (meth)acrylic resin has structural units derived from (meth)acrylic acid ester monomers. The (meth)acrylic acid ester monomers include a (meth)acrylic acid ester monomer A and a (meth)acrylic acid ester monomer B. When the number of carbon atoms in the ester substituent of the (meth)acrylic acid ester monomer A is X, the number of carbon atoms in the ester substituent of the (meth)acrylic acid ester monomer B is 4X. By using a (meth)acrylic resin having the above structure, six-membered ring carbon atoms are less likely to be formed during the decomposition process during sintering, which reduces residue during sintering and further improves low-temperature decomposition properties. Furthermore, the portion of the (meth)acrylic resin derived from (meth)acrylic acid ester monomer A has a short molecular chain of the ester substituent, which exerts strong van der Waals forces, while the portion of the (meth)acrylic resin derived from (meth)acrylic acid ester monomer B has a long molecular chain of the ester substituent, which exerts weak van der Waals forces. The mixture of these two portions allows for the production of molded articles with excellent tensile properties.

[0011] The (meth)acrylic resin has structural units derived from the (meth)acrylic acid ester monomer. Examples of the (meth)acrylic acid ester monomer include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, t-butyl (meth)acrylate, isobutyl (meth)acrylate, n-pentyl (meth)acrylate, isopentyl (meth)acrylate, neopentyl (meth)acrylate, n-hexyl (meth)acrylate, n-heptyl (meth)acrylate, and n-octyl (meth)acrylate.

[0033] Examples of the alkyl (meth)acrylate include alkyl (meth)acrylates having a linear alkyl group or a branched alkyl group, such as n-ethylhexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, n-nonyl (meth)acrylate, isononyl (meth)acrylate, n-decyl (meth)acrylate, isodecyl (meth)acrylate, n-lauryl (meth)acrylate, isolauryl (meth)acrylate, n-tetradecyl (meth)acrylate, n-stearyl (meth)acrylate, and isostearyl (meth)acrylate. Furthermore, examples of the (meth)acrylic acid ester monomer include (meth)acrylates having a polyoxyalkylene structure, such as polytetramethylene glycol monomethacrylate, poly(ethylene glycol-polytetramethylene glycol) monomethacrylate, poly(propylene glycol-tetramethylene glycol) monomethacrylate, propylene glycol-polybutylene glycol monomethacrylate, methoxypolytetramethylene glycol monomethacrylate, methoxypoly(ethylene glycol-polytetramethylene glycol) monomethacrylate, methoxypoly(propylene glycol-tetramethylene glycol) monomethacrylate, and methoxypropylene glycol-polybutylene glycol monomethacrylate. Furthermore, examples of the (meth)acrylic acid ester monomer include (meth)acrylates having a polar group, such as 2-hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, (meth)acrylic acid, glycidyl (meth)acrylate, and glycerol mono(meth)acrylate. Among these, alkyl (meth)acrylates are preferred as the (meth)acrylic acid ester monomers, and methyl (meth)acrylate, ethyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, n-octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, and n-lauryl (meth)acrylate are more preferred. Furthermore, the (meth)acrylic acid ester monomer is preferred because it can reduce residues during sintering and improve low-temperature decomposition properties.

[0012] The (meth)acrylic acid ester monomer is preferably a (meth)acrylic acid ester monomer having a linear ester substituent (hereinafter also referred to as a "linear monomer") or a (meth)acrylic acid ester monomer having a branched ester substituent (hereinafter also referred to as a "branched monomer"), and from the viewpoint of improving the strength of the resulting ceramic green sheet, it preferably contains a (meth)acrylic acid ester monomer having a linear ester substituent and a (meth)acrylic acid ester monomer having a branched ester substituent.

[0013] From the viewpoint of improving the strength of the resulting ceramic green sheet, the ratio of the content of structural units derived from (meth)acrylic acid ester monomers having branched-chain ester substituents to the content of structural units derived from (meth)acrylic acid ester monomers having straight-chain ester substituents in the (meth)acrylic resin (branched monomer / straight-chain monomer) is preferably 0.5 or more and 2.0 or less, more preferably 0.6 or more and more preferably 1.6 or less.

[0014] The ester substituent of the (meth)acrylic acid ester monomer preferably has 1 to 18 carbon atoms, more preferably 1 to 14 carbon atoms, and even more preferably 1 to 12 carbon atoms.

[0015] The (meth)acrylic acid ester monomer preferably includes a (meth)acrylic acid ester monomer having an ester substituent with 1 to 4 carbon atoms. The (meth)acrylic acid ester monomer having an ester substituent with 1 to 4 carbon atoms is preferably methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, t-butyl (meth)acrylate, or isobutyl (meth)acrylate, and more preferably methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, or isobutyl methacrylate. The (meth)acrylic acid ester monomer having an ester substituent with 1 to 4 carbon atoms is more preferably a (meth)acrylic acid ester monomer having an ester substituent with 1 to 3 carbon atoms, and even more preferably a (meth)acrylic acid ester monomer having an ester substituent with 1 to 2 carbon atoms.

[0016] The content of structural units derived from (meth)acrylic acid ester monomers in which the ester substituent has 1 to 4 carbon atoms in the (meth)acrylic resin is preferably 20% by weight or more, preferably 100% by weight or less, and more preferably 30% by weight or more.

[0017] Furthermore, the (meth)acrylic acid ester monomer having an ester substituent with 1 to 4 carbon atoms may be a combination of a (meth)acrylic acid ester monomer having a linear ester substituent with 1 to 4 carbon atoms (hereinafter also referred to as a "C1-4 linear monomer") and a (meth)acrylic acid ester monomer having a branched ester substituent with 3 to 4 carbon atoms (hereinafter also referred to as a "C3-4 branched monomer"). In the (meth)acrylic resin, the ratio of the content of structural units derived from (meth)acrylic ester monomers having branched-chain ester substituents with 3 to 4 carbon atoms to the content of structural units derived from (meth)acrylic ester monomers having linear ester substituents with 1 to 4 carbon atoms (C3-4 branched monomer / C1-4 linear monomer) is preferably 0 or more, and 12 or less, and more preferably 3 or less.

[0018] Furthermore, the content of structural units derived from (meth)acrylic acid ester monomers in which the ester substituent has 1 to 3 carbon atoms in the (meth)acrylic resin is preferably 0% by weight or more, more preferably 3% by weight or more, and even more preferably 5% by weight or more, and is preferably 70% by weight or less, and more preferably 50% by weight or less. Furthermore, the content of structural units derived from (meth)acrylic acid ester monomers in which the ester substituent has 1 to 2 carbon atoms in the (meth)acrylic resin is preferably 0% by weight or more, more preferably 3% by weight or more, and even more preferably 5% by weight or more, and is preferably 70% by weight or less, and more preferably 50% by weight or less.

[0019] The (meth)acrylic acid ester monomer preferably includes a (meth)acrylic acid ester monomer having an ester substituent with 4 to 16 carbon atoms. Examples of the (meth)acrylic acid ester monomer having an ester substituent having 4 to 16 carbon atoms include n-butyl (meth)acrylate, t-butyl (meth)acrylate, isobutyl (meth)acrylate, n-pentyl (meth)acrylate, isopentyl (meth)acrylate, neopentyl (meth)acrylate, n-hexyl (meth)acrylate, n-heptyl (meth)acrylate, n-octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, n-nonyl (meth)acrylate, isononyl (meth)acrylate, n-decyl (meth)acrylate, isodecyl (meth)acrylate, n-lauryl (meth)acrylate, and isolauryl (meth)acrylate. Of these, n-butyl (meth)acrylate, isobutyl (meth)acrylate, n-octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, and n-lauryl (meth)acrylate are preferred, and n-butyl methacrylate, isobutyl methacrylate, n-octyl methacrylate, 2-ethylhexyl methacrylate, and n-lauryl methacrylate are more preferred. The (meth)acrylic acid ester monomer having an ester substituent with 4 to 16 carbon atoms is more preferably a (meth)acrylic acid ester monomer having an ester substituent with 4 to 12 carbon atoms, and even more preferably a (meth)acrylic acid ester monomer having an ester substituent with 4 to 8 carbon atoms.

[0020] The content of structural units derived from (meth)acrylic acid ester monomers in which the ester substituent has 4 to 16 carbon atoms in the (meth)acrylic resin is preferably 30% by weight or more, and preferably 100% by weight or less, more preferably 50% by weight or more, more preferably 97% by weight or less, and even more preferably 95% by weight or less.

[0021] Furthermore, the (meth)acrylic acid ester monomer having an ester substituent with 4 to 16 carbon atoms may be a combination of a (meth)acrylic acid ester monomer having a linear ester substituent with 4 to 16 carbon atoms (hereinafter also referred to as a "C4-16 linear monomer") and a (meth)acrylic acid ester monomer having a branched ester substituent with 4 to 16 carbon atoms (hereinafter also referred to as a "C4-16 branched monomer"). In the (meth)acrylic resin, the ratio of the content of structural units derived from (meth)acrylic ester monomers having a branched-chain ester substituent having 4 to 16 carbon atoms to the content of structural units derived from (meth)acrylic ester monomers having a linear ester substituent having 4 to 16 carbon atoms (C4-16 branched monomer / C4-16 linear monomer) is preferably 0 or more and 3.5 or less, more preferably 0.2 or more, and more preferably 2.5 or less.

[0022] Furthermore, the content of structural units derived from (meth)acrylic acid ester monomers in which the ester substituent has 4 to 12 carbon atoms in the (meth)acrylic resin is preferably 30% by weight or more, and preferably 100% by weight or less, more preferably 50% by weight or more, more preferably 97% by weight or less, and even more preferably 95% by weight or less. Furthermore, the content of structural units derived from (meth)acrylic acid ester monomers in which the ester substituent has 4 to 8 carbon atoms in the (meth)acrylic resin is preferably 25% by weight or more, preferably 95% by weight or less, and more preferably 50% by weight or more.

[0023] The (meth)acrylic acid ester monomer may contain a (meth)acrylic acid ester monomer in which the ester substituent has 17 or more carbon atoms, but preferably does not contain a (meth)acrylic acid ester monomer in which the ester substituent has 17 or more carbon atoms. Furthermore, the (meth)acrylic acid ester monomer may contain a (meth)acrylic acid ester monomer in which the ester substituent has 13 or more carbon atoms, but more preferably does not contain a (meth)acrylic acid ester monomer in which the ester substituent has 13 or more carbon atoms.

[0024] The (meth)acrylic acid ester monomer is preferably an alkyl (meth)acrylate. The (meth)acrylic acid ester monomer may contain a (meth)acrylic acid ester monomer other than the alkyl (meth)acrylate (hereinafter also referred to as "other monomer"), but more preferably does not contain any other monomer.

[0025] From the viewpoint of improving the strength of the resulting ceramic green sheet, the (meth)acrylic acid ester monomer preferably contains a linear monomer and a branched monomer in which the number of carbon atoms in the ester substituents is the same.

[0026] In the (meth)acrylic resin, the ratio of the content of structural units derived from branched monomers to the content of structural units derived from linear monomers having the same number of carbon atoms in the ester substituents (branched monomer / linear monomer (having the same number of carbon atoms in the ester substituents)) is preferably 0.5 or more and 2.0 or less, more preferably 0.6 or more and more preferably 1.7 or less, from the viewpoint of improving the strength of the resulting ceramic green sheet.

[0027] The (meth)acrylic acid ester monomer includes a (meth)acrylic acid ester monomer A (hereinafter also referred to as "monomer A") and a (meth)acrylic acid ester monomer B (hereinafter also referred to as "monomer B"). When the number of carbon atoms of the ester substituent possessed by the monomer A is X, the number of carbon atoms of the ester substituent possessed by the monomer B is 4X. By adopting the above-mentioned constitution, it is possible to obtain a ceramic green sheet having excellent low-temperature decomposition property and high strength.

[0028] As the monomer A, a (meth)acrylic acid ester monomer having an ester substituent with 1 to 4 carbon atoms is preferred, a (meth)acrylic acid ester monomer having an ester substituent with 1 to 3 carbon atoms is more preferred, and a (meth)acrylic acid ester monomer having an ester substituent with 1 to 2 carbon atoms is even more preferred. Furthermore, the above-mentioned monomer A may be a linear monomer or a branched monomer, and is preferably a linear monomer.

[0029] The content of the structural unit derived from the monomer A in the (meth)acrylic resin is preferably 2% by weight or more, and preferably 70% by weight or less, more preferably 3% by weight or more, and more preferably 65% ​​by weight or less. When there are two or more types of (meth)acrylic acid ester monomers corresponding to the above-mentioned monomer A, the content of the structural units derived from the above-mentioned monomer A means the total amount of the (meth)acrylic acid ester monomers corresponding to the above-mentioned monomer A.

[0030] The monomer B may be a linear monomer, a branched monomer, or a monomer containing a linear monomer and a branched monomer, as long as the number of carbon atoms of the ester substituent possessed by the monomer A is 4X, where X is the number of carbon atoms of the ester substituent possessed by the monomer B.

[0031] The content of the structural units derived from the monomer B in the (meth)acrylic resin is preferably 20% by weight or more and 85% by weight or less, more preferably 25% by weight or more and 80% by weight or less. When there are two or more types of (meth)acrylic acid ester monomers corresponding to the above-mentioned monomer B, the content of the structural units derived from the above-mentioned monomer B means the total amount of the (meth)acrylic acid ester monomers corresponding to the above-mentioned monomer B.

[0032] When the monomer B contains a linear monomer and a branched monomer, the ratio of the content of the structural units derived from the branched monomer to the content of the structural units derived from the linear monomer in the structural units derived from the monomer B (branched monomer / linear monomer) is preferably 0.5 or more and preferably 2.0 or less, more preferably 0.6 or more, and more preferably 1.7 or less.

[0033] From the viewpoint of improving decomposition properties, the ratio of the content of the structural units derived from the monomer B to the content of the structural units derived from the monomer A in the (meth)acrylic resin (monomer B / monomer A) is preferably 3 or more and 12 or less, more preferably 4 or more and more preferably 7 or less. In addition, when the number of carbon atoms X of the ester substituent in the above-mentioned monomer A and monomer B is two or more, the above-mentioned ratio (monomer B / monomer A) is calculated by summing up the product of the ratio (monomer B / monomer A) in the cases where X is the same and the total content of the cases where X is the same, and dividing this by the sum of the total content of monomer A and monomer B for each case where X is the same. For example, if the (meth)acrylic resin contains 5% by weight and 15% by weight of structural units derived from monomer A and monomer B where X is 1, respectively, and 10% by weight and 70% by weight of structural units derived from monomer A and monomer B where X is 2, respectively, the ratio (monomer B / monomer A) is (15 / 5×20+70 / 10×80) / (20+80)=6.2.

[0034] In the (meth)acrylic resin, the content of the structural units derived from a (meth)acrylic acid ester monomer different from the structural units derived from the monomer A and the structural units derived from the monomer B may be 0% by weight, is preferably 1% by weight or more, is preferably 80% by weight or less, is more preferably 5% by weight or more, and is more preferably 70% by weight or less.

[0035] The content of the structural units derived from acrylic monomers in the (meth)acrylic resin 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 content of the structural units derived from the acrylic monomers is preferably 0 to 5% by weight, more preferably 0 to 1% by weight, and even more preferably 0% by weight. The acrylic monomer means acrylic acid and acrylic acid ester.

[0036] The weight-average molecular weight (Mw) of the (meth)acrylic resin is preferably 30,000 or more and 5,000,000 or less. When the weight-average molecular weight is 30,000 or more, the tensile performance of the resulting resin sheet is high. When the weight-average molecular weight is 5,000,000 or less, undissolved (meth)acrylic resin is less likely to be produced in the resulting resin sheet, resulting in high tensile performance. For this reason, by setting the weight-average molecular weight within the above range, the strength of the resulting ceramic green sheet can be further increased, allowing for the production of thinner green sheets. The weight average molecular weight (Mw) is more preferably 200,000 or more, more preferably 4,500,000 or less, even more preferably 300,000 or more, still more preferably 4,000,000 or less, and particularly preferably 1,000,000 or more.

[0037] The ratio (Mw / Mn) of the weight-average molecular weight (Mw) to the number-average molecular weight (Mn) of the (meth)acrylic resin is at least 1 and preferably at most 5.0, more preferably at most 4.0, and even more preferably at most 3.5. Within this range, fine undissolved matter is less likely to be generated in the vehicle composition, which can further increase the strength of the ceramic green sheet and prevent voids from being generated in the ceramic laminate after firing. The weight average molecular weight (Mw) and number average molecular weight (Mn) are average molecular weights calculated in terms of polystyrene, and can be obtained by GPC measurement using, for example, column LF-804 (manufactured by Showa Denko KK).

[0038] When the (meth)acrylic resin is in a particulate form, the average particle size of the resin particles is preferably 0.1 μm or more, and preferably 1.0 μm or less, 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, from the viewpoint of solubility. The average particle size can be determined, for example, by measuring the volume average particle size using a laser diffraction / scattering particle size distribution measuring device.

[0039] The CV value of the particle diameter of the (meth)acrylic resin particles is preferably 15% or less, more preferably 12% or less, even more preferably 10% or less, and even more preferably 8% or less. By setting the solubility in the above range, the solubility of the (meth)acrylic resin can be further improved. Improved solubility increases productivity, and the reduction in undissolved resin improves tensile properties. The lower limit is not particularly limited, and is, for example, 0%. The CV value can be calculated from the average particle size and standard deviation of 100 particles observed using a scanning electron microscope. The CV value tends to be smaller when a persulfate such as ammonium persulfate or potassium persulfate is used.

[0040] The (meth)acrylic resin preferably has a Ti value of 1.5 or more and 2.5 or less in a resin solution obtained by dissolving the resin in butyl acetate. By setting the Ti value within this range, the dispersibility of the inorganic particles can be improved, and the strength of the ceramic green sheet can be increased. The Ti value is more preferably 1.6 or more and more preferably 2.2 or less. The Ti value can be determined by calculating the ratio (viscosity (2 rpm) / viscosity (20 rpm)) of the viscosity measured at 25°C and 2 rpm using a BH-type viscometer to the viscosity measured at 25°C and 20 rpm. As the resin solution, for example, a butyl acetate solution containing 15% by weight of (meth)acrylic resin can be used. The Ti value can be adjusted to a preferred range by adjusting the ratio of the content of the structural units derived from the monomer A to the content of the structural units derived from the monomer B.

[0041] The glass transition temperature (Tg) of the (meth)acrylic resin is preferably 30°C or higher, and preferably 85°C or lower, 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. By setting the content within the above range, the amount of plasticizer added can be reduced, and low-temperature decomposition properties can be further improved. The glass transition temperature (Tg) can be measured using, for example, a differential scanning calorimeter (DSC).

[0042] The (meth)acrylic resin preferably has 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 better. The 90 wt % decomposition temperature is preferably 30 to 280°C, more preferably 30 to 270°C, and even more preferably 30 to 260°C.

[0043] Examples of a method for producing the (meth)acrylic resin 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 monomer or the like to prepare a monomer mixture, and then a polymerization initiator and a chain transfer agent are added to the obtained monomer mixture to copolymerize the raw material monomers. The polymerization method is not particularly limited, and examples thereof include emulsion polymerization, suspension polymerization, bulk polymerization, interfacial polymerization, solution polymerization, etc. Among these, emulsion polymerization is preferred.

[0044] 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.

[0045] 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]; Examples of suitable azo compounds include 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.

[0046] 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 more preferably 3.6 parts by weight or less, relative to 100 parts by weight of the raw material monomers. The amount of the polymerization initiator added is preferably 0.03 to 4.0 parts by weight, more preferably 0.05 to 3.6 parts by weight, relative to 100 parts by weight of the raw material monomers.

[0047] Examples of the chain transfer agent include 3-mercapto-1,2-propanediol, 3-mercapto-1-propanol, 3-mercapto-2-butanol, 8-mercapto-1-octanol, 2-mercaptobenzimidazole, mercaptosuccinic acid, and mercaptoacetic acid.

[0048] The amount of the chain transfer agent added is preferably 0.01 part by weight or more, more preferably 0.02 part by weight or more, and is preferably 10.0 parts by weight or less, more preferably 5.0 parts by weight or less, relative to 100 parts by weight of the raw material monomers. The amount of the chain transfer agent added is preferably 0.01 to 10.0 parts by weight, more preferably 0.02 to 5.0 parts by weight, relative to 100 parts by weight of the raw material monomers.

[0049] 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.

[0050] A vehicle composition can be prepared using the above (meth)acrylic resin and a solvent containing an organic solvent. The present invention also includes a vehicle composition containing the above-mentioned (meth)acrylic resin and a solvent containing an organic solvent.

[0051] The content of the (meth)acrylic resin in the vehicle composition is preferably 5% by weight or more, more preferably 10% by weight or more, and is preferably 50% by weight or less, more preferably 40% by weight or less.

[0052] The vehicle composition contains a solvent including 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 methyl acetate, ethyl acetate, butyl acetate, hexyl acetate, dodecyl 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, esters are preferred, with methyl acetate, ethyl acetate, butyl acetate, hexyl acetate and dodecyl acetate being more preferred, ethyl acetate, butyl acetate and hexyl acetate being even more preferred, and butyl acetate being even more preferred.

[0053] The content of the organic solvent in the vehicle composition is not particularly limited, but is preferably 50% by weight or more and 95% by weight or less, more preferably 55% by weight or more and 88.8% by weight or less.

[0054] In the vehicle composition, the solvent preferably further contains water. The content of water in the vehicle composition is preferably 10 ppm by weight or more and 12,000 ppm by weight or less. By including water in the above range, compatibility with the dispersant improves and low-temperature decomposition properties are further improved. The content of water in the vehicle composition is more preferably 300 ppm by weight or more, more preferably 1000 ppm by weight or less, even more preferably 400 ppm by weight or more, and even more preferably 700 ppm by weight or less.

[0055] The content of the solvent in the vehicle composition is not particularly limited, but is preferably 50% by weight or more and 95% by weight or less, more preferably 60% by weight or more and 90% by weight or less.

[0056] The vehicle composition can be produced, for example, by adding an organic solvent, water, etc. to the (meth)acrylic resin obtained by the above method and stirring and mixing.

[0057] A slurry composition can be prepared using the vehicle composition, inorganic particles, and dispersant. A slurry composition containing the vehicle composition, inorganic particles, and a dispersant also constitutes one aspect of the present invention.

[0058] The content of the (meth)acrylic resin 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.

[0059] The content of the organic solvent in the slurry composition is preferably 25% by weight or more and 70% by weight or less, more preferably 30% by weight or more and 60% by weight or less.

[0060] The water content in the above slurry composition is preferably 5 ppm by weight or more, preferably 15,000 ppm by weight or less, more preferably 10 ppm by weight or more, more preferably 12,000 ppm by weight or less, even more preferably 50 ppm by weight or more, even more preferably 10,000 ppm by weight or less, and even more preferably 7,500 ppm by weight or less.

[0061] The content of the solvent in the slurry composition is preferably 25% by weight or more and 70% by weight or less, more preferably 30% by weight or more and 60% by weight or less.

[0062] The slurry composition contains inorganic particles. The inorganic particles are not particularly limited, and examples thereof include glass powder, ceramic powder, phosphor particles, silicon oxide particles, metal particles, and the like.

[0063] 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, as well as glass powders of various silicon oxides such as CaO-Al2O3-SiO2, MgO-Al2O3-SiO2, and LiO2-Al2O3-SiO2. Further, examples of the glass powder include a SnO-B2O3-P2O5-Al2O3 mixture, a PbO-B2O3-SiO2 mixture, a BaO-ZnO-B2O3-SiO2 mixture, a ZnO-Bi2O3-B2O3-SiO2 mixture, a Bi2O3-B2O3-BaO-CuO mixture, a Bi2O3-ZnO-B2O3-Al2O3-SrO mixture, a ZnO-Bi2O3-B2O3 mixture, a Bi2O3-SiO2 mixture, a P2O5-Na2O-CaO-BaO-Al2O3-B2O3 mixture, a P2O5-SnO mixture, a P2O5-SnO-B2O3 mixture, and a P2O5- Other glass powders that can be used include SnO-SiO2 mixtures, CuO-P2O5-RO mixtures, SiO2-B2O3-ZnO-Na2O-Li2O-NaF-V2O5 mixtures, P2O5-ZnO-SnO-R2O-RO mixtures, B2O3-SiO2-ZnO mixtures, B2O3-SiO2-Al2O3-ZrO2 mixtures, SiO2-B2O3-ZnO-R2O-RO mixtures, SiO2-B2O3-Al2O3-RO-R2O mixtures, SrO-ZnO-P2O5 mixtures, SrO-ZnO-P2O5 mixtures, and BaO-ZnO-B2O3-SiO2 mixtures, where R is an element selected from the group consisting of Zn, Ba, Ca, Mg, Sr, Sn, Ni, Fe, and Mn. In particular, glass powder of a PbO-B2O3-SiO2 mixture, or lead-free glass powder such as a lead-free BaO-ZnO-B2O3-SiO2 mixture or a lead-free ZnO-Bi2O3-B2O3-SiO2 mixture is preferred.

[0064] 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. In addition, ITO, FTO, niobium oxide, vanadium oxide, tungsten oxide, lanthanum strontium manganite, lanthanum strontium cobalt ferrite, yttrium stabilized zirconia, gadolinium-doped ceria, nickel oxide, lanthanum chromite, etc. can also be used. The phosphor particles are not particularly limited, and for example, a blue phosphor material, a red phosphor material, a green phosphor material, etc., which are conventionally known as phosphor materials for displays, can be used as the phosphor material. 10 O 17 :Eu series, Y2SiO5:Ce series, CaWO4:Pb series, BaMgAl 14 O 23 :Eu-based, BaMgAl 16 O 27 :Eu-based, BaMg2Al 14 O 23 :Eu-based, BaMg2Al 14 O 27 :Eu-based and ZnS:(Ag,Cd)-based materials are used. Red phosphor materials include, for example, Y2O3:Eu-based, Y2SiO5:Eu-based, Y3Al5O 12:Eu system, Zn3(PO4)2:Mn system, YBO3:Eu system, (Y,Gd)BO3:Eu system, GdBO3:Eu system, ScBO3:Eu system, LuBO3:Eu system, etc. Green phosphor materials include, for example, Zn2SiO4:Mn system, BaAl 12 O 19 :Mn-based, SrAl 13 O 19 :Mn-based, CaAl 12 O 19 :Mn series, YBO3:Tb series, BaMgAl 14 O 23 :Mn-based, LuBO3:Tb-based, GdBO3:Tb-based, ScBO3:Tb-based, Sr6Si3O3Cl4:Eu-based. Others include ZnO:Zn-based, ZnS:(Cu,Al)-based, ZnS:Ag-based, Y2O2S:Eu-based, ZnS:Zn-based, (Y,Cd)BO3:Eu-based, BaMgAl 12 O 23 :Eu-based materials can also be used.

[0065] 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. In addition, metals such as copper and iron, which have good adsorption properties with carboxyl groups, amino groups, amide groups, etc. and are easily oxidized, can also be suitably used. These metal particles may be used alone or in combination of two or more types. The metal particles may be metal complexes, or may be various types of carbon black, carbon nanotubes, or the like.

[0066] The inorganic particles preferably contain lithium or titanium. Specifically, for example, low-melting glass such as LiO2·Al2O3·SiO2-based inorganic glass, Li2S-M x S yLithium sulfur-based glasses such as (M=B, Si, Ge, P), lithium cobalt composite oxides such as LiCeO2, lithium manganese composite oxides such as LiMnO4, lithium nickel composite oxides, lithium vanadium composite oxides, lithium zirconium composite oxides, lithium hafnium composite oxides, lithium silicophosphate (Li 3.5 Si 0.5 P 0.5 O4), lithium titanium phosphate (LiTi2(PO4)3), lithium titanate (Li4Ti5O 12 ), Li 4 / 3 Ti 5 / 3 O4, LiCoO2, lithium germanium phosphate (LiGe2(PO4)3), Li2-SiS-based glass, Li4GeS4-Li3PS4-based glass, LiSiO3, LiMn2O4, Li2S-P2S5-based glass and ceramics, Li2O-SiO2, Li2O-V2O5-SiO2, LiS-SiS2-Li4SiO4-based glass, ionic conductive oxides such as LiPON, lithium oxide compounds such as Li2O-P2O5-B2O3 and Li2O-GeO2Ba, Li x Al y Ti z (PO4)3-based glass, La x Li y TiO z Li-based glass x Ge y P z O4-based glass, Li7La3Zr2O 12 Li-based glass v Si w P x S y Cl z Lithium niobium oxides such as LiNbO3, lithium alumina compounds such as Li-β-alumina, 14 Examples include lithium zinc oxides such as Zn(GeO4)4.

[0067] 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 inorganic particles have an average particle size of preferably 0.01 to 5 μm, more preferably 0.05 to 3 μm, and still more preferably 0.1 to 1 μm. The average particle size can be determined, for example, by measuring the volume average particle size using a laser diffraction / scattering particle size distribution measuring device.

[0068] The content of the inorganic particles in the slurry composition is preferably 20% by weight or more and 90% by weight or less, which provides sufficient viscosity, excellent coating properties, and excellent dispersibility of the inorganic particles. The content of the inorganic particles is more preferably 25% by weight or more, more preferably 70% by weight or less, even more preferably 30% by weight or more, even more preferably 60% by weight or less, even more preferably 40% by weight or more, and even more preferably 55% by weight or less.

[0069] The slurry composition contains a dispersant. Suitable examples of the dispersant include fatty acids, aliphatic amines, alkanolamides, and phosphate esters. Silane coupling agents may also be added. The fatty acid is not particularly limited, and examples thereof 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, beef tallow fatty acid, and hardened castor fatty acid. Of these, lauric acid, stearic acid, and oleic acid are preferred. The aliphatic amine is not particularly limited, and examples thereof include laurylamine, myristylamine, cetylamine, stearylamine, oleylamine, alkyl(coconut)amine, alkyl(hardened beef tallow)amine, alkyl(beef tallow)amine, and alkyl(soybean)amine. The alkanolamide is not particularly limited, and examples thereof include coconut fatty acid diethanolamide, beef tallow fatty acid diethanolamide, lauric acid diethanolamide, and oleic acid diethanolamide. The phosphate ester is not particularly limited, and examples thereof include polyoxyethylene alkyl ether phosphate ester and polyoxyethylene alkyl allyl ether phosphate ester.

[0070] The content of the dispersant in the slurry composition is preferably 0.1% by weight or more and 1.5% by weight or less, more preferably 0.15% by weight or more and 1.0% by weight or less.

[0071] The above-mentioned slurry composition may further contain additives such as a plasticizer and a surfactant. 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.

[0072] 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 one with an HLB value of 10 to 20. The HLB value is used as an index of the hydrophilicity and lipophilicity of a surfactant, and several calculation methods have been proposed. For example, for an ester surfactant, the HLB value is defined as 20 (1-S / A), where S is the saponification value and A is the acid value of the fatty acid constituting the surfactant. Specifically, nonionic surfactants having polyethylene oxide with alkylene ether attached to the fatty chain are preferred, and specific examples of suitable surfactants include polyoxyethylene lauryl ether and polyoxyethylene cetyl ether. Although the nonionic surfactants have good thermal decomposition properties, adding a large amount can reduce the thermal decomposition properties of the inorganic particle dispersion slurry composition. Therefore, the preferred upper limit of the content is 5% by weight.

[0073] The viscosity of the slurry composition is not particularly limited, but when measured at 25°C using a Brookfield viscometer, the viscosity is preferably 200 mPa·s or more, more preferably 500 mPa·s or more, and is preferably 100,000 mPa·s or less, more preferably 50,000 mPa·s or less. The viscosity is preferably 200 to 100,000 mPa·s, more preferably 500 to 50,000 mPa·s. By setting the content 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. In addition, problems such as indelible die coating marks can be prevented, and excellent printability can be achieved.

[0074] 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 three-roll mill, etc. The order of addition of the components of the slurry composition can be appropriately determined.

[0075] The above-mentioned slurry composition can be used to produce electronic components. An electronic component made using the above slurry composition also constitutes one aspect of the present invention. Examples of the electronic components include die attach paste (ACP), die attach film (ACF), via electrodes for TSV and TGV, touch panels, various circuits for RFID and sensor substrates, various die bonding agents, sealants for MEMS devices, and electrode materials for solar cells, multilayer ceramic capacitors, LTCC, silicon capacitors, all-solid-state batteries, etc. In addition to the electrode circuit applications, the material can also be used for antibacterial materials, electromagnetic wave shielding, catalysts, fluorescent materials, etc.

[0076] For example, the slurry composition can be applied to a support film that has been subjected to a release treatment on one side, the organic solvent is dried, and the film is molded to produce an inorganic particle-dispersed molded product. The shape of the inorganic particle dispersion molded product is not particularly limited, but may be, for example, a sheet.

[0077] 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.

[0078] 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.

[0079] 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, and cellulose. The thickness of the support film is preferably, for example, 10 to 100 μm. It is also preferable that the surface of the support film is subjected to a release treatment, which allows the support film to be easily peeled off in the transfer step.

[0080] The above slurry composition can be applied and dried to produce a molded product containing dispersed inorganic particles. Furthermore, by using the above-mentioned slurry composition and inorganic particle dispersion molded product in a conductive paste for external electrodes, a multilayer ceramic capacitor, which is an electronic component, can be produced.

[0081] A method for producing the multilayer ceramic capacitor includes a step of printing a conductive paste on the inorganic particle dispersion molding and drying it to produce a dielectric sheet, and a step of laminating the dielectric sheets.

[0082] The conductive paste contains a conductive powder. The material of the conductive powder is not particularly limited as long as it is a material having conductivity, 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.

[0083] 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.

[0084] In the method for manufacturing the multilayer 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 300 to 1500°C, thereby obtaining a large number of component elements.

[0085] Next, a conductive paste for external electrodes containing the above-mentioned (meth)acrylic resin is applied to both end surfaces of each of these component elements by dipping, and then this is dried at 100 to 200°C and then fired at 300 to 800°C in a reducing atmosphere to form external electrodes on both end surfaces of the component elements.

[0086] Next, the external electrodes are subjected to electrolytic plating to sequentially form a Cu film, a Ni film, and a Sn film on the external electrodes, thereby obtaining a multilayer ceramic capacitor. [Effects of the Invention]

[0087] The present invention provides a (meth)acrylic resin that can produce a ceramic laminate that can be further thinned by achieving both excellent low-temperature decomposition properties of a slurry composition and high strength of a ceramic green sheet, and also provides a vehicle composition, a slurry composition, and an electronic component that contain the (meth)acrylic resin. DETAILED DESCRIPTION OF THE INVENTION

[0088] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.

[0089] Example 12~17, Reference Examples 1~ 11、18~ 19, Comparative Examples 1 to 9) (Preparation of (meth)acrylic resin particles) A 2 L separable flask equipped with a stirrer, a condenser, a thermometer, a hot water bath, and a nitrogen gas inlet was prepared, and a total of 100 parts by weight of monomers was added to the 2 L separable flask so as to obtain the composition shown in Table 1. Furthermore, 900 parts by weight of water was mixed to obtain a monomer mixture. The following monomers were used: MMA: Methyl methacrylate (ester substituent carbon number: 1) EMA: Ethyl methacrylate (ester substituent carbon number: 2) nPMA: n-propyl methacrylate (ester substituent carbon number: 3) nBMA: n-butyl methacrylate (ester substituent carbon number: 4) iBMA: isobutyl methacrylate (ester substituent carbon number: 4) OMA: n-octyl methacrylate (ester substituent carbon number: 8) 2EHMA: 2-ethylhexyl methacrylate (number of carbon atoms in the ester substituent: 8) LMA: n-lauryl methacrylate (ester substituent carbon number: 12) MA: methyl acrylate (ester substituent carbon number: 1) BA: butyl acrylate (ester substituent carbon number: 4)

[0090] 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, and the water bath was heated to 80° C. with stirring. Thereafter, a chain transfer agent and a polymerization initiator were added in the amounts shown in Table 1 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 100°C to remove water, yielding (meth)acrylic resin particles. The chain transfer agent and polymerization initiator used were as follows: <Chain transfer agent> CT-1: 3-mercapto-1,2-propanediol <Polymerization initiator> KPS: Potassium persulfate (Fujifilm Wako Pure Chemical Industries, Ltd.)

[0091] (Preparation of vehicle composition for dispersing inorganic particles) To 10 parts by weight of the obtained (meth)acrylic resin particles, 90 parts by weight of a solvent having the composition shown in Table 2 was added, and the mixture was stirred until homogenous, to obtain a vehicle composition for dispersing inorganic particles.

[0092] (Preparation of inorganic particle dispersion slurry composition) To the obtained vehicle composition for dispersing inorganic particles, a solvent, a dispersant, and inorganic particles were added in the formulation shown in Table 2, and the mixture was kneaded with a high-speed stirrer to obtain an inorganic particle dispersion slurry composition. The solvents used in the preparation of the vehicle composition for dispersing inorganic particles were used in the same proportions. The dispersants and inorganic particles used were as follows: <Dispersant> Nopcosperse 092 (manufactured by Sanyo Chemical Industries, Ltd.) <Inorganic particles> Barium titanate (BT-02, Sakai Chemical Industry Co., Ltd., average particle size 0.2 μm)

[0093] <Evaluation> Example Reference Example 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 and 3.

[0094] (1) Ti value 85 parts by weight of butyl acetate was added to 15 parts by weight of the obtained (meth)acrylic resin particles, and the mixture was heated to 80°C while stirring. The mixture was kept at 80°C for 12 hours with stirring, and then cooled to obtain a resin solution. The viscosity of the obtained resin solution was measured using a BH-type viscometer with a No. 5 rotor at 25°C and 2 rpm. The viscosity was also measured in the same manner at 25°C and 20 rpm, and the Ti value was calculated according to the following formula. Ti value = viscosity (2 rpm) / viscosity (20 rpm)

[0095] (2) Average particle size D and CV value of particle size The obtained (meth)acrylic resin particles were observed using a scanning electron microscope (Regulus8220 manufactured by Hitachi High-Technologies Corporation), and the particle sizes of 100 particles were measured. The CV value was calculated using the average particle size D [μm] and the standard deviation σ of the particle sizes using the following formula. Particle size CV value [%] = σ / D × 100

[0096] (3) Weight average molecular weight (Mw) The weight average molecular weight (Mw) of the obtained (meth)acrylic resin particles was measured in terms of polystyrene by gel permeation chromatography using an LF-804 (manufactured by SHOKO Corporation) as a column.

[0097] (4) Low temperature decomposition (TGDTA) The obtained inorganic particle dispersion slurry composition was packed into a TGDTA platinum pan and heated from 30°C at a rate of 5°C / min under a nitrogen atmosphere to evaporate the solvent and thermally decompose the resin and dispersant. The time (minutes) until 90% by weight degreasing was completed (the weight was 40.4% by weight) was then measured.

[0098] (5) Sintering residue (TGDTA) The obtained (meth)acrylic resin particles were packed into a TGDTA platinum pan, heated from 30°C to 350°C at a rate of 5°C / min in a nitrogen atmosphere, and held for 2 hours to thermally decompose the (meth)acrylic resin particles. The ratio of the weight after measurement to the weight before measurement was measured as the sintering residue.

[0099] (6) Dispersibility (6-1) Filterability 2 ml of the obtained inorganic particle dispersion slurry composition was placed in a 2.5 ml syringe, and a syringe needle having an outer diameter of 0.81 mm, an inner diameter of 0.51 mm, and a length of 38 mm was attached to the tip of the syringe. A force of 5 kgf was applied, and the time until all of the slurry composition came out of the tip of the syringe needle was measured. If the time it takes for the slurry composition to completely come out of the tip of the syringe needle is short, it can be said that the filterability is excellent, and when the filterability is excellent, it can be said that the effect of inhibiting aggregation of inorganic particles is high and the dispersibility is excellent.

[0100] (6-2) Surface roughness Using a screen printer, a screen plate, and a printing glass substrate, an inorganic particle dispersion slurry composition was printed under an environment of a temperature of 23°C and a humidity of 50%, and the solvent was dried in a fan oven for 30 minutes under conditions of 100°C. Using the obtained printed pattern, the surface roughness was measured at 10 points using a surface roughness meter (Surfcom, manufactured by Tokyo Seimitsu Co., Ltd.). The following screen printing machine, screen plate, and printing glass substrate were used. Screen printing machine (MT-320TV, manufactured by Microtec) Screen plate (Tokyo Process Services, ST500, emulsion 2 μm, 2012 patterns, screen frame 320 mm x 320 mm) Printed glass substrate (soda glass, 150mm x 150mm, thickness 1.5mm) A small surface roughness means that the dispersibility of inorganic particles is excellent.

[0101] (7) Particles The obtained (meth)acrylic resin particles were diluted with a mixed solvent of ethanol and toluene (weight ratio 1:1) so that the resin content was 2% by weight, and the particle size distribution of the polyvinyl acetal resin in 10 mL of this solution was measured using a particle counter ("KL-11A", manufactured by Rion Co., Ltd.). The number of particles with a particle size of 0.5 to 1.0 μm or more per mL of solution was confirmed. In addition, for particles with a particle size of 0.5 to 1.0 μm, the particle volume was calculated assuming that the particles were true spheres with a particle size of 0.75 μm, and the proportion (10%) of particles with a particle size of 0.5 to 1.0 μm was calculated based on the measurement results. -8 The volume percent of the ceramic laminate was calculated. Fewer particles means fewer voids in the ceramic laminate, which is therefore considered to be superior.

[0102] (8) Tensile test The resulting (meth)acrylic resin particles were dissolved in butyl acetate, and the resulting resin solution was applied to a release-treated PET film using an applicator, followed by drying for 10 minutes in a 100°C air-blowing oven to produce a 20μm-thick resin sheet. Using graph paper as a cover film, 1cm-wide strip test pieces were cut with scissors. The obtained test pieces were subjected to tensile tests at 23°C and 50 RH using an autograph AG-IS (Shimadzu Corporation) with a chuck distance of 3 cm and a tensile speed of 10 mm / min, and the stress-strain characteristics (yield stress, elongation at break, and tensile performance (yield stress × elongation at break)) were confirmed. If the strength of the resin sheet is high, it can be predicted that the strength of the resulting ceramic green sheet will also be high.

[0103] (9) Thin film test The obtained inorganic particle dispersion slurry composition was applied to a release-treated PET film using an applicator and dried for 10 minutes in a 100°C air oven to produce green sheets with dried thicknesses of 1.0 μm, 2.0 μm, 3.0 μm, 4.0 μm, 5.0 μm, 6.0 μm, 7.0 μm, 8.0 μm, 9.0 μm, and 10.0 μm. The green sheets were checked for tears when peeled from the PET film, and the one without tears and with the smallest thickness was used as the evaluation result.

[0104] [Table 1]

[0105] [Table 2]

[0106] [Table 3] [Industrial Applicability]

[0107] The present invention provides a (meth)acrylic resin that can produce a ceramic laminate that can be further thinned by achieving both excellent low-temperature decomposition properties of a slurry composition and high strength of a ceramic green sheet, and also provides a vehicle composition, a slurry composition, and an electronic component that contain the (meth)acrylic resin.

Claims

1. having a structural unit derived from a (meth)acrylic acid ester monomer, The (meth)acrylic acid ester monomer includes a (meth)acrylic acid ester monomer A and a (meth)acrylic acid ester monomer B, When the number of carbon atoms of the ester substituent possessed by the (meth)acrylic acid ester monomer A is X, the number of carbon atoms of the ester substituent possessed by the (meth)acrylic acid ester monomer B is 4X; the number of carbon atoms X of the ester substituent of the (meth)acrylic acid ester monomer A is 1, The (meth)acrylic acid ester monomer further includes 2-ethylhexyl (meth)acrylate, a ratio of the content of the structural units derived from the (meth)acrylic acid ester monomer B to the content of the structural units derived from the (meth)acrylic acid ester monomer A (monomer B / monomer A) is 4 or more and 7 or less; the content of the structural unit derived from the (meth)acrylic acid ester monomer A is 5% by weight or more, A (meth)acrylic resin having a Ti value of 1.5 or more and 2.5 or less when dissolved in butyl acetate.

2. A (meth)acrylic resin as described in claim 1, wherein the content of constituent units derived from (meth)acrylic acid ester monomer B is 20% by weight or more.

3. 3. The (meth)acrylic resin according to claim 1, wherein the (meth)acrylic acid ester monomer is a methacrylic acid ester monomer.

4. 3. The (meth)acrylic resin according to claim 1 or 2, wherein the (meth)acrylic acid ester monomer comprises a (meth)acrylic acid ester monomer having a branched-chain ester substituent and a (meth)acrylic acid ester monomer having a linear-chain ester substituent, the ester substituents having the same number of carbon atoms.

5. 5. The (meth)acrylic resin according to claim 4, wherein the ratio of the content of structural units derived from (meth)acrylic ester monomers having branched-chain ester substituents to the content of structural units derived from (meth)acrylic ester monomers having straight-chain ester substituents, wherein the ester substituents have the same number of carbon atoms ((meth)acrylic ester monomers having branched-chain ester substituents / (meth)acrylic ester monomers having straight-chain ester substituents (the ester substituents have the same number of carbon atoms)) is 0.5 or more and 2.0 or less.

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

7. The vehicle composition according to claim 6, further comprising water, the content of said water being 10 ppm by weight or more and 12,000 ppm by weight or less.

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

9. A slurry composition comprising the vehicle composition according to claim 7, inorganic particles, and a dispersant.

10. An electronic part obtained by using the slurry composition according to claim 8.

11. An electronic part obtained by using the slurry composition according to claim 9.

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