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

Abstract

The present invention provides a (meth)acrylic resin with which it is possible to achieve both superior low-temperature decomposability of a slurry composition and high strength of a ceramic green sheet, and with which a thinner ceramic layered body can be produced. The present invention also provides a vehicle composition including the (meth)acrylic resin, as well as a slurry composition and an electronic component. The present invention is a (meth)acrylic resin having structural units derived from (meth)acrylic acid ester monomers, wherein the (meth)acrylic acid ester monomers include a (meth)acrylic acid ester monomer A and a (meth)acrylic acid ester monomer B, and when the carbon number of the ester substituent of the (meth)acrylic acid ester monomer A is treated as X, the carbon number of the ester substituent of the (meth)acrylic acid ester monomer B is 4X.

Description

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

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

[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 ceramic molding, and in particular describes the use of polyvinyl butyral resin or polyvinyl acetal resin to thin the sheet. Patent Document 2 also describes a methacrylic acid ester copolymer obtained by copolymerizing isobutyl methacrylate, 2-ethylhexyl methacrylate, and a hydroxyl group-containing methacrylic acid ester in a predetermined ratio. It is also stated that the use of such binder resins can exhibit good moldability and degreasing properties.

[0005] JP2011-84433A JP10-167836A

[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 binders are dispersed, resulting in poor dispersibility 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.

[0008] The present disclosure (1) is a (meth)acrylic resin having structural units derived from (meth)acrylic acid ester monomers, the (meth)acrylic acid ester monomers including a (meth)acrylic acid ester monomer A and a (meth)acrylic acid ester monomer B, wherein when the number of carbon atoms of the ester substituent of the (meth)acrylic acid ester monomer A is X, the number of carbon atoms of the ester substituent of the (meth)acrylic acid ester monomer B is 4X. The present disclosure (2) is a (meth)acrylic resin of the present disclosure (1), in which the ratio of the content of structural units derived from the (meth)acrylic acid ester monomer B to the content of structural units derived from the (meth)acrylic acid ester monomer A (monomer B / monomer A) is 3 or more and 12 or less. The present disclosure (3) is a (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 a 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), in which 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, in which the ester substituents have the same number of carbon atoms. The present disclosure (6) is the (meth)acrylic resin of the present disclosure (5), in which 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 linear-chain ester substituents, in which the ester substituents have the same number of carbon atoms, is 0.5 or more and 2.0 or less ((meth)acrylic acid ester monomers having branched-chain ester substituents / (meth)acrylic acid ester monomers having linear-chain ester substituents (the ester substituents have the same number of carbon atoms)). 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 is 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. Furthermore, they have 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 (meth)acrylic acid ester monomer A and (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, it is difficult for a six-membered ring carbon to be formed during the decomposition process during sintering, thereby reducing residue during sintering and further improving 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 products with excellent tensile properties.

[0011] The (meth)acrylic resin has a structural unit 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.

[0043] 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. 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. 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, the (meth)acrylic acid ester monomer is preferably an alkyl (meth)acrylate, and more preferably methyl (meth)acrylate, ethyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, n-octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, or n-lauryl (meth)acrylate. Furthermore, the (meth)acrylic acid ester monomer is preferred because it can reduce residues during sintering and further improve low-temperature decomposition properties.

[0012] The (meth)acrylic acid ester monomer is preferably a (meth)acrylic acid ester monomer having a straight-chain ester substituent (hereinafter also referred to as a "straight-chain monomer") or a (meth)acrylic acid ester monomer having a branched-chain 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 straight-chain ester substituent and a (meth)acrylic acid ester monomer having a branched-chain 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. As the (meth)acrylic acid ester monomer having an ester substituent with 1 to 4 carbon atoms, methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, t-butyl (meth)acrylate, and isobutyl (meth)acrylate are preferred, and methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, and isobutyl methacrylate are more preferred. As the (meth)acrylic acid ester monomer having an ester substituent with 1 to 4 carbon atoms, 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.

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

[0018] The content of structural units derived from (meth)acrylic acid ester monomers having an ester substituent with 1 to 3 carbon atoms in the (meth)acrylic resin is preferably 0% by weight or more, more preferably 3% by weight or more, even more preferably 5% by weight or more, and 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 having an ester substituent with 1 to 2 carbon atoms in the (meth)acrylic resin is preferably 0% by weight or more, more preferably 3% by weight or more, even more preferably 5% by weight or more, and 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 in which the ester substituent has 4 to 16 carbon atoms. Examples of the (meth)acrylic acid ester monomer in which the ester substituent has 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. As the (meth)acrylic acid ester monomer having an ester substituent with 4 to 16 carbon atoms, (meth)acrylic acid ester monomers having an ester substituent with 4 to 12 carbon atoms are more preferred, and (meth)acrylic acid ester monomers having an ester substituent with 4 to 8 carbon atoms are even more preferred.

[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 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 in which the ester substituent has 4 to 16 carbon atoms may be a combination of a (meth)acrylic acid ester monomer having a straight-chain ester substituent having 4 to 16 carbon atoms (hereinafter also referred to as a "C4-16 straight-chain monomer") and a (meth)acrylic acid ester monomer having a branched-chain ester substituent having 4 to 16 carbon atoms (hereinafter also referred to as a "C4-16 branched monomer"). The ratio of the content of structural units derived from (meth)acrylic acid ester monomers having branched-chain ester substituents having 4 to 16 carbon atoms to the content of structural units derived from (meth)acrylic acid ester monomers having straight-chain ester substituents having 4 to 16 carbon atoms in the (meth)acrylic resin (C4-16 branched monomer / C4-16 straight-chain 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] The content of structural units derived from (meth)acrylic acid ester monomers having an ester substituent with 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 having an ester substituent with 4 to 8 carbon atoms in the (meth)acrylic resin is preferably 25% by weight or more, and 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 having an ester substituent with 17 or more carbon atoms, but preferably does not contain a (meth)acrylic acid ester monomer having an ester substituent with 17 or more carbon atoms. The (meth)acrylic acid ester monomer may contain a (meth)acrylic acid ester monomer having an ester substituent with 13 or more carbon atoms, but more preferably does not contain a (meth)acrylic acid ester monomer having an ester substituent with 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] From the viewpoint of improving the strength of the resulting ceramic green sheet, 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 their ester substituents in the (meth)acrylic resin (branched monomer / linear monomer (having the same number of carbon atoms in their 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.

[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 employing the above-described configuration, it is possible to exhibit excellent low-temperature decomposition properties and obtain a ceramic green sheet with high strength.

[0028] The monomer A is preferably a (meth)acrylic acid ester monomer having an ester substituent with a carbon number of 1 to 4, more preferably a (meth)acrylic acid ester monomer having an ester substituent with a carbon number of 1 to 3, and even more preferably a (meth)acrylic acid ester monomer having an ester substituent with a carbon number of 1 to 2. The monomer A may be a linear monomer or a branched monomer, and is preferably a linear monomer.

[0029] The content of the structural units 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 (meth)acrylic acid ester monomers corresponding to the monomer A, the content of the structural units derived from the monomer A means the total amount of the (meth)acrylic acid ester monomers corresponding to the 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 preferably 85% by weight or less, more preferably 25% by weight or more, and more preferably 80% by weight or less. When there are two or more (meth)acrylic acid ester monomers corresponding to the monomer B, the content of the structural units derived from the monomer B means the total amount of the (meth)acrylic acid ester monomers corresponding to the 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 decomposability, 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 7 or less. When the number of carbon atoms X of the ester substituent in the monomer A and monomer B is two or more, the ratio (monomer B / monomer A) is calculated by adding up the product of the ratio (monomer B / monomer A) for monomers having the same X and the total content of monomers having the same X, and dividing this by the sum of the total content of monomers A and B for each monomer having the same X. For example, when 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 constituent units derived from a (meth)acrylic acid ester monomer different from the constituent units derived from the monomer A and the constituent 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 the acrylic monomer 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 monomer is preferably 0 to 5% by weight, more preferably 0 to 1% by weight, and even more preferably 0% by weight. The acrylic monomer refers to acrylic acid and acrylic acid esters.

[0036] The weight-average molecular weight (Mw) of the (meth)acrylic resin is preferably 30,000 or more and preferably 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 improved. 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 improved 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, even 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 1 or more, preferably 5.0 or less, more preferably 4.0 or less, and even more preferably 3.5 or less. 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 occurring in the ceramic laminate after firing. 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 K.K.).

[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 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 analyzer.

[0039] The CV value of the particle size 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 CV value within 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 performance. 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 achieving this range, the dispersibility of inorganic particles is improved, thereby increasing the strength of the ceramic green sheet. 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 (2 rpm) measured at 25°C and 2 rpm using a BH-type viscometer to the viscosity (20 rpm) measured at 25°C and 20 rpm. Furthermore, for example, a butyl acetate solution containing 15% by weight of the (meth)acrylic resin can be used as the resin solution. The Ti value can be adjusted to a preferred range by adjusting the ratio between the content of the structural units derived from Monomer A and the content of the structural units derived from 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 temperature 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) or the like.

[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 methods 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 include emulsion polymerization, suspension polymerization, bulk polymerization, interfacial polymerization, and solution polymerization. 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]; water-soluble azo compounds such as [2,2'-azobis[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 (meth)acrylic resin and a solvent containing an organic solvent. A vehicle composition containing the (meth)acrylic resin and a solvent containing an organic solvent also constitutes one aspect of the present invention.

[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 the water in the vehicle composition is preferably 10 ppm by weight or more and preferably 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 the water in the vehicle composition is more preferably 300 ppm by weight or more, more preferably 1,000 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 may 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 the mixture.

[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 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, and the inorganic particles are not particularly limited, and examples thereof include glass powder, ceramic powder, phosphor particles, silicon oxide particles, and metal particles.

[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, and CaO—Al ２ O ３ -SiO ２ system, MgO-Al ２ O ３ -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 O３ -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 O ５ -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 -Al２ 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.

[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. 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 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 O１７ : 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, GdBO ３ : 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 ２S: Eu-based, ZnS: Zn-based, (Y, Cd)BO ３ :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. 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 particles may be used alone or in combination of two or more types. In addition to metal complexes, various carbon blacks, carbon nanotubes, and the like may also be used as the metal particles.

[0066] 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 S ｙ 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 ), Li２ -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 Ti ｚ (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.

[0067] The average particle size of the inorganic particles is preferably 0.01 μm or more and 5 μm or less, more preferably 0.05 μm or more, more preferably 3 μm or less, even more preferably 0.1 μm or more, and even more preferably 1 μm or less. The average particle size of the inorganic particles is preferably 0.01 to 5 μm, more preferably 0.05 to 3 μm, and even 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 analyzer.

[0068] The content of the inorganic particles in the slurry composition is preferably 20% by weight or more and preferably 90% by weight or less. Within this range, the slurry composition can have 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. 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.

[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 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.

[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 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%.

[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 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 viscosity within the above range, it becomes possible for the resulting inorganic particle-dispersed sheet to maintain a predetermined shape after coating by a die coating printing method or the like. Furthermore, problems such as indelible die coating marks can be prevented, resulting in excellent printability.

[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 triple roll, etc. The order of addition of the components of the slurry composition can be appropriately determined.

[0075] Electronic components can be produced using the above-mentioned slurry composition. Electronic components produced using the above-mentioned slurry composition also constitute one aspect of the present invention. Examples of the electronic components include die attach paste (ACP), die attach film (ACF), via electrodes for TSV / 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, and 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.

[0076] 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.

[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 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, 10 to 100 μm. In addition, the surface of the support film is preferably subjected to a release treatment, which makes it easy to peel off the support film in the transfer step.

[0080] 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.

[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 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.

[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 green 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 a dipping method, and then the applied paste 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 successively form a Cu film, a Ni film, and a Sn film on the external electrodes, thereby obtaining a multilayer ceramic capacitor.

[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.

[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] (Examples 1 to 19, Comparative Examples 1 to 9) (Preparation of (meth)acrylic resin particles) A ​​2 L 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 2 L separable flask so as to obtain the formulation 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 (number of carbon atoms in the ester substituent: 1) EMA: ethyl methacrylate (number of carbon atoms in the ester substituent: 2) nPMA: n-propyl methacrylate (number of carbon atoms in the ester substituent: 3) nBMA: n-butyl methacrylate (number of carbon atoms in the ester substituent: 4) iBMA: isobutyl methacrylate (number of carbon atoms in the ester substituent: 4) OMA: n-octyl methacrylate (number of carbon atoms in the ester substituent: 8) 2EHMA: 2-ethylhexyl methacrylate (number of carbon atoms in the ester substituent: 8) LMA: n-lauryl methacrylate (number of carbon atoms in the ester substituent: 12) MA: methyl acrylate (number of carbon atoms in the ester substituent: 1) BA: butyl acrylate (number of carbon atoms in the ester substituent: 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 while stirring. Subsequently, 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 polymerization was terminated by cooling to room temperature. The resulting resin solution was then dried in an oven at 100°C to remove water. 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 <Polymerization initiator> KPS: potassium persulfate (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.)

[0091] (Preparation of vehicle composition for dispersing inorganic particles) 90 parts by weight of a solvent having the formulation shown in Table 2 was added to 10 parts by weight of the obtained (meth)acrylic resin particles, and the mixture was stirred until homogeneous 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 according to 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 solvent used in preparing the vehicle composition for dispersing inorganic particles was used in the same ratio. The dispersant and inorganic particles used were as follows. <Dispersant> Nopcosperse 092 (manufactured by Sanyo Chemical Industries, Ltd.) <Inorganic particles> Barium titanate (BT-02, manufactured by Sakai Chemical Industry Co., Ltd., average particle size 0.2 μm)

[0093] <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 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 while 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 rotor No. 5 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 based on the following formula: Ti value = viscosity (2 rpm) / viscosity (20 rpm).

[0095] (2) Average Particle Diameter D and CV Value of Particle Diameter The obtained (meth)acrylic resin particles were observed using a scanning electron microscope (Regulus 8220 manufactured by Hitachi High-Technologies Corporation), and the particle diameters of 100 particles were measured. The CV value was calculated from the average particle diameter D [μm] and the standard deviation σ of the particle diameters using the following formula: CV value of particle diameter [%] = 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 platinum pan of a TGDTA, and the temperature was raised 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. Thereafter, the time (minutes) until 90 wt % degreasing was completed (the weight was 40.4 wt %) was measured.

[0098] (5) Sintering residue (TGDTA) The obtained (meth)acrylic resin particles were packed into a platinum pan of a TGDTA, and the temperature was raised from 30°C to 350°C at a rate of 5°C / min in a nitrogen atmosphere, and maintained at that temperature 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 the slurry composition was completely discharged from the tip of the syringe needle was measured. A short time until the slurry composition was completely discharged from the tip of the syringe needle can be said to have excellent filterability, and an excellent filterability can be said to have a high effect of inhibiting aggregation of inorganic particles and excellent dispersibility.

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

[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 of particles with a particle size of 0.5 to 1.0 μm (10%) was calculated based on the obtained 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. The film was then dried in a 100°C air-blowing oven for 10 minutes to produce a 20 μm-thick resin sheet. Using graph paper as a cover film, 1 cm-wide strip-shaped test specimens were prepared with scissors. Tensile tests were performed on the resulting test specimens using an Autograph AG-IS (Shimadzu Corporation) at 23°C and 50 RH conditions, with a chuck distance of 3 cm and a tensile speed of 10 mm / min, to confirm the stress-strain characteristics (yield stress, elongation at break, and tensile performance (yield stress × elongation at break)). It can be predicted that if the strength of the resin sheet is high, 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 with the smallest thickness among those without tears was used as the evaluation result.

[0104]

[0105]

[0106]

[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. A composition comprising a (meth)acrylic resin and an organic solvent, Further containing water, the content of the water is 10 ppm by weight or more and 12000 ppm by weight or less, The (meth)acrylic resin has 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, A vehicle composition, wherein when the number of carbon atoms of an ester substituent possessed by the (meth)acrylic acid ester monomer A is X, the number of carbon atoms of an ester substituent possessed by the (meth)acrylic acid ester monomer B is 4X.

2. The (meth)acrylic resin is a vehicle composition described in claim 1, wherein the ratio (monomer B / monomer A) of the content of constituent units derived from (meth)acrylic acid ester monomer B to the content of constituent units derived from (meth)acrylic acid ester monomer A is 3 or more and 12 or less.

3. A vehicle composition as described in claim 1 or 2, wherein the (meth)acrylic acid ester monomer constituting the (meth)acrylic resin is a methacrylic acid ester monomer.

4. A vehicle composition as described in claim 1 or 2, wherein the (meth)acrylic resin has a Ti value of 1.5 or more and 2.5 or less when dissolved in butyl acetate.

5. A vehicle composition described in claim 1 or 2, wherein the (meth)acrylic acid ester monomers constituting the (meth)acrylic resin include a (meth)acrylic acid ester monomer having a branched-chain ester substituent and a (meth)acrylic acid ester monomer having a straight-chain ester substituent, the number of carbon atoms of the ester substituents being the same.

6. A vehicle composition as described in claim 5, wherein in the (meth)acrylic resin, the ratio of the content of constituent units derived from (meth)acrylic acid ester monomers having branched-chain ester substituents to the content of constituent units derived from (meth)acrylic acid ester monomers having straight-chain ester substituents, the ester substituents having the same number of carbon atoms, ((meth)acrylic acid ester monomers having branched-chain ester substituents / (meth)acrylic acid 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.

7. A slurry composition comprising the vehicle composition according to claim 1 or 2, inorganic particles, and a dispersant.

8. An electronic part, comprising the slurry composition according to claim 7.

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