Resin composition for ceramic green sheet, method for producing ceramic green sheet, and method for producing multilayer ceramic electronic component

Abstract

A resin composition for ceramic green sheets according to the present invention contains a ceramic powder, a binder and an organic solvent; the binder is a polyvinyl butyral; and the organic solvent is a mixed solvent that contains methyl cyclohexane and ethanol.

Description

[Technical Field]

[0001] The present invention relates to a resin composition for a ceramic green sheet, a method for producing a ceramic green sheet, and a method for producing a multilayer ceramic electronic component. [Background technology]

[0002] Multilayer ceramic electronic components such as multilayer ceramic capacitors are generally manufactured through the following steps. First, a resin composition for ceramic green sheets (ceramic slurry) in which ceramic powder is dispersed is prepared. Next, the ceramic green sheet resin composition is applied to a sheet and then dried to produce a ceramic green sheet. After forming an internal electrode pattern on the obtained ceramic green sheet, multiple ceramic green sheets with the internal electrode patterns formed thereon are stacked, and if necessary, ceramic green sheets without internal electrode patterns are stacked on both main surfaces to produce a laminate. The obtained laminate is fired to produce a ceramic sintered body. If necessary, external electrodes are formed on the outer surfaces of the ceramic sintered body. Through the above steps, a multilayer ceramic electronic component is obtained.

[0003] Patent Document 1 discloses a polyvinyl acetal resin having an average degree of polymerization of more than 4500 and not more than 10000, and having an acetal group content of 45 to 80 mol %, a hydroxyl group content of 18 to 50 mol %, and an acetyl group content of 0.5 to 20 mol %. Patent Document 1 also discloses a ceramic green sheet composition containing the polyvinyl acetal resin and an organic solvent, a ceramic green sheet made using the ceramic green sheet composition, and a multilayer ceramic capacitor made using the ceramic green sheet.

[0004] Patent Document 2 discloses a method for producing a ceramic green sheet, which includes a step of applying a coating slurry containing an organic solvent, ceramic powder, and an organic resin binder to a sheet, and a step of continuously drying the sheet-applied slurry in a drying furnace, wherein the drying step comprises an initial drying step and a later drying step, and the initial drying step is characterized in that the applied sheet-form slurry is dried until the organic solvent content reaches 20 to 40 mass %.

[0005] Patent Document 3 discloses a method for producing ceramic green sheets by mixing and dispersing ceramic powder and an organic binder resin in an organic solvent to obtain a ceramic slurry, and then forming ceramic green sheets using the ceramic slurry, characterized in that prior to mixing the ceramic powder, the ceramic powder is humidified to have a moisture content of 0.2 to 1.5% by weight. Patent Document 3 also discloses a method for producing a multilayer ceramic electronic component, characterized in that it includes the steps of humidifying the ceramic powder to have a moisture content of 0.2 to 1.5% by weight, mixing the humidified ceramic powder and an organic binder resin in an organic solvent to obtain a ceramic slurry, forming the ceramic slurry into sheets to obtain ceramic green sheets, stacking a plurality of the ceramic green sheets with internal electrodes interposed therebetween to obtain a laminate, firing the resulting laminate to obtain a ceramic sintered body, and forming external electrodes on the outer surfaces of the ceramic sintered body. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Publication No. 2020-56015 [Patent Document 2] Japanese Patent Application Laid-Open No. 2007-91526 [Patent Document 3] Japanese Patent Application Publication No. 11-348015 Summary of the Invention [Problem to be solved by the invention]

[0007] However, the inventions described in Patent Documents 1 to 3 leave room for improvement in terms of producing multilayer ceramic electronic components with fewer structural defects, such as internal electrode layers peeling off from ceramic layers and voids occurring at the boundaries between the ends of internal electrode layers and ceramic layers.

[0008] An object of the present invention is to provide a resin composition for ceramic green sheets that can be used to obtain multilayer ceramic electronic components with reduced structural defects. Another object of the present invention is to provide a method for producing a ceramic green sheet using the resin composition for ceramic green sheets, and a method for producing a multilayer ceramic electronic component. [Means for solving the problem]

[0009] The resin composition for a ceramic green sheet of the present invention contains ceramic powder, a binder, and an organic solvent, wherein the binder is polyvinyl butyral, and the organic solvent is a mixed solvent containing methylcyclohexane and ethanol.

[0010] The method for producing a ceramic green sheet of the present invention includes a step of forming the resin composition for a ceramic green sheet of the present invention into a sheet.

[0011] The method for producing a multilayer ceramic electronic component of the present invention includes the steps of: preparing a ceramic green sheet by molding the resin composition for ceramic green sheet of the present invention into a sheet; forming an internal electrode pattern on the ceramic green sheet; stacking a plurality of the ceramic green sheets on which the internal electrode pattern has been formed to prepare a laminate; and firing the laminate to prepare a ceramic sintered body having a structure in which internal electrode layers are stacked via ceramic layers. [Effects of the Invention]

[0012] According to the present invention, it is possible to provide a resin composition for a ceramic green sheet that can produce a multilayer ceramic electronic component with reduced structural defects. Furthermore, according to the present invention, it is possible to provide a method for producing a ceramic green sheet and a method for producing a multilayer ceramic electronic component using the resin composition for a ceramic green sheet. [Brief explanation of the drawings]

[0013] [Figure 1] FIG. 1 is a cross-sectional view schematically showing an example of a multilayer ceramic capacitor. [Figure 2] FIG. 2 is a cross-sectional view taken along line II-II of the laminate constituting the multilayer ceramic capacitor shown in FIG. [Figure 3] FIG. 3 is a cross-sectional view that schematically shows an example of a structural defect in which a gap occurs at the boundary between the end of an internal electrode layer and a ceramic layer. [Figure 4] FIG. 4 is a cross-sectional view showing a schematic example of a structural defect in which an internal electrode layer is peeled off from a ceramic layer. DETAILED DESCRIPTION OF THE INVENTION

[0014] The resin composition for ceramic green sheets, the method for producing ceramic green sheets, and the method for producing multilayer ceramic electronic components of the present invention will be described below. Note that the present invention is not limited to the following configurations, and may be modified as appropriate within the scope of the present invention. Furthermore, a combination of multiple individual preferred configurations described below also constitutes the present invention.

[0015] The drawings shown below are schematic diagrams, and the dimensions, aspect ratio, scale, etc. may differ from those of the actual product.

[0016] The resin composition for a ceramic green sheet of the present invention contains ceramic powder, a binder, and an organic solvent.

[0017] The resin composition for a ceramic green sheet of the present invention is characterized in that the binder is polyvinyl butyral, and the organic solvent is a mixed solvent containing methylcyclohexane and ethanol.

[0018] In the resin composition for ceramic green sheets of the present invention, a mixed solvent containing methylcyclohexane and ethanol is used as the organic solvent, thereby enabling the production of ceramic green sheets that can be used to obtain high-quality chip components. Specifically, by producing ceramic green sheets with a moderate amount of voids remaining, the amount of plastic deformation of the ceramic green sheets can be increased, thereby reducing structural defects that occur during lamination and compression bonding of the ceramic green sheets. As a result, high-quality chip components can be obtained.

[0019] Conventionally, toluene / ethanol mixed solvents have been used as organic solvents. Unlike toluene / ethanol mixed solvents, methylcyclohexane / ethanol mixed solvents have an azeotropic composition and a low azeotropic point of 72°C (1 atm) (compared to 78°C (1 atm) for toluene / ethanol mixed solvents). This increases the volatility of the organic solvent compared to conventional solvents, which is thought to result in a moderate amount of voids remaining in the ceramic green sheets. Furthermore, because methylcyclohexane is a solvent with a lower polarity than toluene, it has slightly poorer compatibility with polyvinyl butyral, which is used as a binder. As a result, the tendency for a methylcyclohexane-rich phase to form may be a factor in the high porosity of the ceramic green sheets.

[0020] In the resin composition for a ceramic green sheet of the present invention, the mixed solvent preferably further contains at least one solvent selected from the group consisting of isopropanol, methyl ethyl ketone, methyl propyl ketone, and methyl isobutyl ketone. By blending at least one of these solvents into the organic solvent, high solubility of polyvinyl butyral can be maintained even when the blending amount of methylcyclohexane is increased. As a result, undissolved polyvinyl butyral can be suppressed, thereby reducing short circuits in chip components.

[0021] In the resin composition for a ceramic green sheet of the present invention, the mixed solvent may further contain one or more solvents selected from the group consisting of isopropanol, methyl ethyl ketone, methyl propyl ketone, and methyl isobutyl ketone. For example, the mixed solvent may contain isopropanol and methyl ethyl ketone in addition to methylcyclohexane and ethanol.

[0022] In the resin composition for a ceramic green sheet of the present invention, the content of methylcyclohexane in the mixed solvent is not particularly limited, but if the content of methylcyclohexane is too low, it becomes difficult to obtain the effect of reducing structural defects, while if the content of methylcyclohexane is too high, it becomes difficult to prepare the resin composition. In consideration of these points, the content of methylcyclohexane is preferably 20 parts by weight or more and 80 parts by weight or less per 100 parts by weight of the total of methylcyclohexane and ethanol.

[0023] In the resin composition for a ceramic green sheet of the present invention, the content of ethanol in the mixed solvent is not particularly limited, but it is preferable that the content of ethanol is 20 parts by weight or more and 80 parts by weight or less per 100 parts by weight of the total of methylcyclohexane and ethanol.

[0024] In the resin composition for a ceramic green sheet of the present invention, when the mixed solvent contains isopropanol, it is preferable that the content of methylcyclohexane is 20 parts by weight or more and 80 parts by weight or less, and the content of isopropanol is 0.4 parts by weight or more and 40 parts by weight or less, relative to 100 parts by weight of the total of methylcyclohexane and ethanol.

[0025] In the resin composition for a ceramic green sheet of the present invention, when the mixed solvent contains methyl ethyl ketone, it is preferable that the content of methylcyclohexane is 20 parts by weight or more and 80 parts by weight or less, and the content of methyl ethyl ketone is 0.4 parts by weight or more and 40 parts by weight or less, relative to 100 parts by weight of the total of methylcyclohexane and ethanol.

[0026] For example, when the mixed solvent contains isopropanol and methyl ethyl ketone, it is preferable that the content of methylcyclohexane is 20 parts by weight or more and 80 parts by weight or less, the content of isopropanol is 0.4 parts by weight or more and 40 parts by weight or less, and the content of methyl ethyl ketone is 0.4 parts by weight or more and 40 parts by weight or less, relative to 100 parts by weight of the total of methylcyclohexane and ethanol.

[0027] In the resin composition for a ceramic green sheet of the present invention, when the mixed solvent contains methyl propyl ketone, it is preferable that the content of methyl cyclohexane is 20 parts by weight or more and 80 parts by weight or less, and the content of methyl propyl ketone is 0.4 parts by weight or more and 40 parts by weight or less, relative to 100 parts by weight of the total of methyl cyclohexane and ethanol.

[0028] In the resin composition for a ceramic green sheet of the present invention, when the mixed solvent contains methyl isobutyl ketone, it is preferable that the content of methylcyclohexane is 20 parts by weight or more and 80 parts by weight or less, and the content of methyl isobutyl ketone is 0.4 parts by weight or more and 40 parts by weight or less, relative to 100 parts by weight of the total of methylcyclohexane and ethanol.

[0029] In the resin composition for a ceramic green sheet of the present invention, the mixed solvent may further contain toluene. However, if the toluene content is too high, the effect of methylcyclohexane is difficult to obtain. Therefore, when the mixed solvent contains toluene, the toluene content is preferably 35 parts by weight or less per 100 parts by weight of the total of methylcyclohexane and ethanol. When the mixed solvent contains toluene, the toluene content may be, for example, 20 parts by weight or less, 10 parts by weight or less, 5 parts by weight or less, 2 parts by weight or less, or 0.1 parts by weight or less per 100 parts by weight of the total of methylcyclohexane and ethanol.

[0030] In the resin composition for a ceramic green sheet of the present invention, the mixed solvent preferably does not contain toluene. Here, "does not contain toluene" does not strictly mean that toluene is not contained, i.e., the toluene content is 0 parts by weight, but means that toluene is substantially not contained, for example, including the case where toluene is contained as an unavoidable impurity.

[0031] Furthermore, the methylcyclohexane / ethanol-based mixed solvent contained in the resin composition for a ceramic green sheet of the present invention has solubility and wiping properties comparable to those of conventional toluene / ethanol-based mixed solvents when used to clean equipment during dispersion or molding, making the mixed solvent contained in the resin composition for a ceramic green sheet of the present invention suitable for use as a cleaning liquid.

[0032] The method for producing a ceramic green sheet of the present invention includes a step of forming the resin composition for a ceramic green sheet of the present invention into a sheet.

[0033] A ceramic green sheet can be produced by molding the resin composition for a ceramic green sheet of the present invention into a sheet shape. Specifically, the ceramic green sheet can be produced by applying the resin composition for a ceramic green sheet of the present invention to a sheet shape and then drying it.

[0034] The method for producing a multilayer ceramic electronic component of the present invention includes the steps of: preparing a ceramic green sheet by molding the resin composition for ceramic green sheet of the present invention into a sheet; forming an internal electrode pattern on the ceramic green sheet; stacking a plurality of the ceramic green sheets on which the internal electrode pattern has been formed to prepare a laminate; and firing the laminate to prepare a ceramic sintered body having a structure in which internal electrode layers are stacked via ceramic layers.

[0035] A ceramic green sheet obtained by molding the resin composition for a ceramic green sheet of the present invention into a sheet can be used to produce multilayer ceramic electronic parts such as multilayer ceramic capacitors.

[0036] Fig. 1 is a cross-sectional view schematically showing an example of a multilayer ceramic capacitor, Fig. 2 is a cross-sectional view taken along line II-II of a laminate constituting the multilayer ceramic capacitor shown in Fig. 1.

[0037] The multilayer ceramic capacitor 1 shown in Fig. 1 includes a laminate 10 in which internal electrode layers 12 are stacked with ceramic layers 11 interposed therebetween. The internal electrode layers 12 are alternately exposed on the surface of the laminate 10 at end faces 15 and 16 of the laminate 10. A pair of external electrodes 13 and 14 electrically connected to the internal electrode layers 12 is formed on each of the end faces 15 and 16 of the laminate 10.

[0038] In the method for manufacturing a multilayer ceramic electronic component of the present invention, a laminate is produced by laminating a plurality of ceramic green sheets on which internal electrode patterns are formed. At this time, as shown in Fig. 2, it is preferable to produce a laminate 10 by laminating a plurality of ceramic green sheets on which internal electrode patterns are formed to form an internal electrode holding layer 17, and by laminating ceramic green sheets on both main surfaces of the internal electrode holding layer 17 on which internal electrode patterns are not formed to form protective layers 18 and 19.

[0039] The resulting laminate is fired to produce a ceramic sintered body having a structure in which internal electrode layers are laminated via ceramic layers. If necessary, external electrodes are formed on the outer surfaces of the ceramic sintered body. This process produces a multilayer ceramic electronic component such as a multilayer ceramic capacitor.

[0040] The present specification discloses the following:

[0041] <1> containing ceramic powder, a binder, and an organic solvent; the binder is polyvinyl butyral, The resin composition for a ceramic green sheet, wherein the organic solvent is a mixed solvent containing methylcyclohexane and ethanol.

[0042] <2> The mixed solvent further contains at least one solvent selected from the group consisting of isopropanol, methyl ethyl ketone, methyl propyl ketone, and methyl isobutyl ketone. <1> The resin composition for a ceramic green sheet according to claim 1.

[0043] <3> The content of the methylcyclohexane is 20 parts by weight or more and 80 parts by weight or less relative to 100 parts by weight of the total of the methylcyclohexane and the ethanol. <1> or <2> The resin composition for a ceramic green sheet according to claim 1.

[0044] <4> the content of the methylcyclohexane is 20 parts by weight or more and 80 parts by weight or less, relative to 100 parts by weight of the total of the methylcyclohexane and the ethanol; and when the mixed solvent contains the isopropanol, the content of the isopropanol is 0.4 parts by weight or more and 40 parts by weight or less; when the mixed solvent contains the methyl ethyl ketone, the content of the methyl ethyl ketone is 0.4 parts by weight or more and 40 parts by weight or less; when the mixed solvent contains the methyl propyl ketone, the content of the methyl propyl ketone is 0.4 parts by weight or more and 40 parts by weight or less; and when the mixed solvent contains the methyl isobutyl ketone, the content of the methyl isobutyl ketone is 0.4 parts by weight or more and 40 parts by weight or less; <2> The resin composition for a ceramic green sheet according to claim 1.

[0045] <5> The mixed solvent further contains toluene. <1> ~ <4> 10. The resin composition for a ceramic green sheet according to claim 9, wherein the resin composition is a polyimide resin.

[0046] <6> The mixed solvent does not contain toluene. <1> ~ <4> 10. The resin composition for a ceramic green sheet according to claim 9, wherein the resin composition is a polyimide resin.

[0047] <7> <1> ~ <6> 10. A method for producing a ceramic green sheet, comprising a step of forming the resin composition for a ceramic green sheet according to any one of claims 1 to 9 into a sheet.

[0048] <8> <1> ~ <6> a step of forming the resin composition for a ceramic green sheet according to any one of the above into a sheet to produce a ceramic green sheet; forming an internal electrode pattern on the ceramic green sheet; a step of laminating a plurality of the ceramic green sheets on which the internal electrode patterns are formed to form a laminate; and firing the laminate to produce a ceramic sintered body having a structure in which internal electrode layers are laminated via ceramic layers. [Example]

[0049] Examples will be given below that more specifically disclose the resin composition for ceramic green sheets, the method for producing ceramic green sheets, and the method for producing multilayer ceramic electronic components of the present invention, but the present invention is not limited to these examples.

[0050] Example 1 [Preparation of ceramic slurry] A ceramic slurry (resin composition for ceramic green sheets) in which the ceramic powder was dispersed was prepared by mixing 32 parts by weight of ceramic powder (particle size converted to specific surface area (SSA): 0.3 μm) whose main component was barium titanate with 4 parts by weight of polyvinyl butyral (PVB) as a binder and 64 parts by weight of a methylcyclohexane / ethanol mixed solvent as an organic solvent.

[0051] The polyvinyl butyral used had a degree of polymerization of 1700 and a hydroxyl group content of 34 mol%. The organic solvent had a composition ratio (weight ratio) of methylcyclohexane / ethanol = 50 / 50. The ceramic powder was dispersed by mixing and grinding using a bead mill. To prevent foreign matter from being mixed into the sample, the disperser and media were washed with the same mixed solvent as above before and after use.

[0052] [Preparation of ceramic green sheets] The prepared ceramic slurry was formed into ceramic green sheets with a thickness of 1 μm using a molding machine.

[0053] [Fabrication of multilayer ceramic capacitors] An internal electrode pattern was formed on the obtained ceramic green sheet by screen printing a Ni paste containing an organic binder and then drying it. The thickness of the internal electrode pattern was adjusted to 0.8 μm as a dried coating. Next, 300 ceramic green sheets with the internal electrode pattern formed thereon were stacked to form an internal electrode holding layer, and 20 plain ceramic green sheets without the internal electrode pattern formed thereon were stacked on each of the front and back surfaces to form a protective layer.

[0054] The laminate comprising the internal electrode holding layer and the protective layer having the above-described configuration was subjected to a binder removal process and a firing process, and then external electrodes were formed on both ends of the laminate, thereby producing a multilayer ceramic capacitor as a multilayer ceramic electronic component.

[0055] The resulting ceramic green sheets and multilayer ceramic capacitors were evaluated as follows.

[0056] [Sheet surface roughness] The surface roughness Ra of the ceramic green sheets was measured using an optical interference type shape measuring instrument Zygo NewView7300 manufactured by Canon Marketing Japan.

[0057] Sheet Density Five pieces measuring 5 cm×8 cm square were punched out from the ceramic green sheet, and the weight and thickness of each piece were measured to calculate the sheet density.

[0058] [Short circuit] Using a Yokogawa Hewlett-Packard 4278A testing machine, 100 samples (multilayer ceramic capacitors) were evaluated for the presence or absence of short circuits under conditions of 25°C, 120Hz, and 1.0V.

[0059] [Structural defects] Fig. 3 is a cross-sectional view showing an example of a structural defect in which a gap occurs at the boundary between the end of an internal electrode layer and a ceramic layer, and Fig. 4 is a cross-sectional view showing an example of a structural defect in which an internal electrode layer is peeled off from a ceramic layer.

[0060] Cross sections of 100 chip components (multilayer ceramic capacitors) were polished as shown in Figures 3 and 4, and the presence of internal structural defects was evaluated. Voids as shown in Figure 3 or peeling as shown in Figure 4 were counted as structural defects.

[0061] The evaluation results are shown in Table 1.

[0062] Example 2 A ceramic slurry was prepared in the same manner as in Example 1, except that a mixed solvent of methylcyclohexane / ethanol was used as the organic solvent and that the composition ratio (weight ratio) was set to 80 / 20, and then ceramic green sheets and multilayer ceramic capacitors were fabricated. The obtained ceramic green sheets and multilayer ceramic capacitors were evaluated in the same manner as in Example 1. The evaluation results are shown in Table 1.

[0063] Example 3 A ceramic slurry was prepared in the same manner as in Example 1, except that a mixed solvent of methylcyclohexane and ethanol was used as the organic solvent and that the composition ratio (weight ratio) was set to 20 / 80, and then ceramic green sheets and multilayer ceramic capacitors were fabricated. The obtained ceramic green sheets and multilayer ceramic capacitors were evaluated in the same manner as in Example 1. The evaluation results are shown in Table 1.

[0064] Example 4 A ceramic slurry was prepared in the same manner as in Example 1, except that a mixed solvent of methylcyclohexane / ethanol / isopropanol (IPA) was used as the organic solvent and the composition ratio (weight ratio) was set to 50 / 50 / 20, and then ceramic green sheets and multilayer ceramic capacitors were fabricated. The obtained ceramic green sheets and multilayer ceramic capacitors were evaluated in the same manner as in Example 1. The evaluation results are shown in Table 1.

[0065] Example 5 A ceramic slurry was prepared in the same manner as in Example 1, except that a mixed solvent of methylcyclohexane / ethanol / methyl ethyl ketone (MEK) was used as the organic solvent and the composition ratio (weight ratio) was set to 50 / 50 / 20, and then ceramic green sheets and multilayer ceramic capacitors were fabricated. The obtained ceramic green sheets and multilayer ceramic capacitors were evaluated in the same manner as in Example 1. The evaluation results are shown in Table 1.

[0066] Example 6 A ceramic slurry was prepared in the same manner as in Example 1, except that a mixed solvent of methylcyclohexane / ethanol / methyl propyl ketone (MPK) was used as the organic solvent and the composition ratio (weight ratio) was set to 50 / 50 / 20, and then ceramic green sheets and multilayer ceramic capacitors were fabricated. The obtained ceramic green sheets and multilayer ceramic capacitors were evaluated in the same manner as in Example 1. The evaluation results are shown in Table 1.

[0067] Example 7 A ceramic slurry was prepared in the same manner as in Example 1, except that a mixed solvent of methylcyclohexane / ethanol / methyl isobutyl ketone (MIBK) was used as the organic solvent and the composition ratio (weight ratio) was set to 50 / 50 / 20, and then ceramic green sheets and multilayer ceramic capacitors were fabricated. The obtained ceramic green sheets and multilayer ceramic capacitors were evaluated in the same manner as in Example 1. The evaluation results are shown in Table 1.

[0068] Example 8 A ceramic slurry was prepared in the same manner as in Example 1, except that a mixed solvent of methylcyclohexane / ethanol / IPA / MEK was used as the organic solvent and the composition ratio (weight ratio) was set to 50 / 50 / 0.4 / 2, and then ceramic green sheets and multilayer ceramic capacitors were fabricated. The obtained ceramic green sheets and multilayer ceramic capacitors were evaluated in the same manner as in Example 1. The evaluation results are shown in Table 1.

[0069] Example 9 A ceramic slurry was prepared in the same manner as in Example 1, except that a mixed solvent of methylcyclohexane / ethanol / IPA / MEK was used as the organic solvent and the composition ratio (weight ratio) was set to 80 / 20 / 6 / 0.4, and then ceramic green sheets and multilayer ceramic capacitors were fabricated. The obtained ceramic green sheets and multilayer ceramic capacitors were evaluated in the same manner as in Example 1. The evaluation results are shown in Table 1.

[0070] Example 10 A ceramic slurry was prepared in the same manner as in Example 1, except that a mixed solvent of methylcyclohexane / ethanol / IPA / MEK was used as the organic solvent and the composition ratio (weight ratio) was set to 50 / 50 / 6 / 10, and then ceramic green sheets and multilayer ceramic capacitors were fabricated. The obtained ceramic green sheets and multilayer ceramic capacitors were evaluated in the same manner as in Example 1. The evaluation results are shown in Table 1.

[0071] Example 11 A ceramic slurry was prepared in the same manner as in Example 1, except that a mixed solvent of methylcyclohexane / ethanol / IPA / MEK was used as the organic solvent and the composition ratio (weight ratio) was set to 50 / 50 / 6 / 20, and then ceramic green sheets and multilayer ceramic capacitors were fabricated. The obtained ceramic green sheets and multilayer ceramic capacitors were evaluated in the same manner as in Example 1. The evaluation results are shown in Table 1.

[0072] Example 12 A ceramic slurry was prepared in the same manner as in Example 1, except that a mixed solvent of methylcyclohexane / ethanol / IPA / MEK was used as the organic solvent and the composition ratio (weight ratio) was set to 50 / 50 / 6 / 30, and then ceramic green sheets and multilayer ceramic capacitors were fabricated. The obtained ceramic green sheets and multilayer ceramic capacitors were evaluated in the same manner as in Example 1. The evaluation results are shown in Table 1.

[0073] Example 13 A ceramic slurry was prepared in the same manner as in Example 1, except that a mixed solvent of methylcyclohexane / ethanol / IPA / MEK was used as the organic solvent and the composition ratio (weight ratio) was set to 50 / 50 / 6 / 40, and then ceramic green sheets and multilayer ceramic capacitors were fabricated. The obtained ceramic green sheets and multilayer ceramic capacitors were evaluated in the same manner as in Example 1. The evaluation results are shown in Table 1.

[0074] Example 14 A ceramic slurry was prepared in the same manner as in Example 1, except that a mixed solvent of methylcyclohexane / ethanol / IPA / MEK was used as the organic solvent and the composition ratio (weight ratio) was set to 50 / 50 / 40 / 1, and then ceramic green sheets and multilayer ceramic capacitors were fabricated. The obtained ceramic green sheets and multilayer ceramic capacitors were evaluated in the same manner as in Example 1. The evaluation results are shown in Table 1.

[0075] Example 15 A ceramic slurry was prepared in the same manner as in Example 1, except that a mixed solvent of methylcyclohexane / ethanol / IPA / MEK was used as the organic solvent and the composition ratio (weight ratio) was set to 70 / 30 / 4 / 1, and then ceramic green sheets and multilayer ceramic capacitors were fabricated. The obtained ceramic green sheets and multilayer ceramic capacitors were evaluated in the same manner as in Example 1. The evaluation results are shown in Table 1.

[0076] Example 16 A ceramic slurry was prepared in the same manner as in Example 1, except that a mixed solvent of methylcyclohexane / ethanol / IPA / MEK was used as the organic solvent and the composition ratio (weight ratio) was set to 60 / 40 / 5 / 1, and then ceramic green sheets and multilayer ceramic capacitors were fabricated. The obtained ceramic green sheets and multilayer ceramic capacitors were evaluated in the same manner as in Example 1. The evaluation results are shown in Table 1.

[0077] Example 17 A ceramic slurry was prepared in the same manner as in Example 1, except that a mixed solvent of methylcyclohexane / ethanol / IPA / MEK was used as the organic solvent and the composition ratio (weight ratio) was set to 50 / 50 / 6 / 1, and then ceramic green sheets and multilayer ceramic capacitors were fabricated. The obtained ceramic green sheets and multilayer ceramic capacitors were evaluated in the same manner as in Example 1. The evaluation results are shown in Table 1.

[0078] Example 18 A ceramic slurry was prepared in the same manner as in Example 1, except that a mixed solvent of methylcyclohexane / ethanol / IPA / MEK was used as the organic solvent and the composition ratio (weight ratio) was set to 40 / 60 / 7 / 1, and then ceramic green sheets and multilayer ceramic capacitors were fabricated. The obtained ceramic green sheets and multilayer ceramic capacitors were evaluated in the same manner as in Example 1. The evaluation results are shown in Table 1.

[0079] Example 19 A ceramic slurry was prepared in the same manner as in Example 1, except that a mixed solvent of methylcyclohexane / ethanol / IPA / MEK was used as the organic solvent and the composition ratio (weight ratio) was set to 30 / 70 / 8 / 1, and then ceramic green sheets and multilayer ceramic capacitors were fabricated. The obtained ceramic green sheets and multilayer ceramic capacitors were evaluated in the same manner as in Example 1. The evaluation results are shown in Table 1.

[0080] Example 20 A ceramic slurry was prepared in the same manner as in Example 1, except that a mixed solvent of methylcyclohexane / ethanol / IPA / MEK was used as the organic solvent and the composition ratio (weight ratio) was set to 20 / 80 / 9 / 2, and then ceramic green sheets and multilayer ceramic capacitors were fabricated. The obtained ceramic green sheets and multilayer ceramic capacitors were evaluated in the same manner as in Example 1. The evaluation results are shown in Table 1.

[0081] Example 21 A ceramic slurry was prepared in the same manner as in Example 1, except that a mixed solvent of methylcyclohexane / ethanol / IPA / MEK / toluene was used as the organic solvent and the composition ratio (weight ratio) was set to 29 / 71 / 8 / 1 / 35, and then ceramic green sheets and multilayer ceramic capacitors were fabricated. The obtained ceramic green sheets and multilayer ceramic capacitors were evaluated in the same manner as in Example 1. The evaluation results are shown in Table 1.

[0082] (Comparative Example 1) A ceramic slurry was prepared in the same manner as in Example 1, except that a mixed solvent of ethanol / IPA / MEK / toluene was used as the organic solvent and the composition ratio (weight ratio) was set to 50 / 6 / 1 / 50, and then ceramic green sheets and multilayer ceramic capacitors were fabricated. The obtained ceramic green sheets and multilayer ceramic capacitors were evaluated in the same manner as in Example 1. The evaluation results are shown in Table 1.

[0083] [Table 1]

[0084] As can be seen from Table 1, in Comparative Example 1, a multilayer ceramic capacitor with many internal structural defects was obtained.

[0085] On the other hand, in Example 1, a multilayer ceramic capacitor with fewer internal structural defects was obtained compared to Comparative Example 1. This is thought to be the result of the fact that a ceramic green sheet with higher plasticity and lower density was obtained compared to Comparative Example 1.

[0086] In Examples 2 and 3, similar to Example 1, multilayer ceramic capacitors with fewer internal structural defects than Comparative Example 1 were obtained.

[0087] In Example 4, similar to Example 1, a multilayer ceramic capacitor with fewer internal structural defects was obtained compared to Comparative Example 1. Also, there were fewer short circuits compared to Example 1. This is thought to be because the addition of IPA to the mixed solvent increases the solubility of PVB.

[0088] In Example 5, similar to Example 1, a multilayer ceramic capacitor with fewer internal structural defects was obtained compared to Comparative Example 1. Also, there were fewer short circuits compared to Example 1. This is thought to be because the addition of MEK to the mixed solvent increases the solubility of PVB.

[0089] In Example 6, similar to Example 1, a multilayer ceramic capacitor with fewer internal structural defects was obtained compared to Comparative Example 1. Also, there were fewer short circuits compared to Example 1. This is thought to be because the addition of MPK to the mixed solvent increases the solubility of PVB.

[0090] In Example 7, similar to Example 1, a multilayer ceramic capacitor with fewer internal structural defects was obtained compared to Comparative Example 1. Also, there were fewer short circuits compared to Example 1. This is thought to be because the addition of MIBK to the mixed solvent increases the solubility of PVB.

[0091] In Example 8, similar to Example 1, a multilayer ceramic capacitor with fewer internal structural defects was obtained compared to Comparative Example 1. Also, there were fewer short circuits compared to Example 1. This is thought to be because the addition of IPA and MEK to the mixed solvent increases the solubility of PVB.

[0092] In addition, in Examples 9 to 20, the same effects as in Example 8 were obtained.

[0093] In Example 21, although the mixed solvent contains toluene, it also contains methylcyclohexane, so that a ceramic green sheet with a lower density than that of Comparative Example 1 is obtained, and a multilayer ceramic capacitor with fewer internal structural defects is obtained. [Explanation of symbols]

[0094] 1. Multilayer ceramic capacitors 10 Laminate 11 ceramic layer 12 Internal electrode layer 13, 14 External electrode 15, 16 End face of laminate 17 Internal electrode holding layer 18, 19 Protective layer

Claims

1. containing ceramic powder, a binder, and an organic solvent; the binder is polyvinyl butyral; the organic solvent is a mixed solvent containing methylcyclohexane and ethanol, The resin composition for a ceramic green sheet, wherein the mixed solvent further contains at least one solvent selected from the group consisting of isopropanol, methyl ethyl ketone, methyl propyl ketone, and methyl isobutyl ketone.

2. 2. The resin composition for a ceramic green sheet according to claim 1, wherein the content of said methylcyclohexane is 20 parts by weight or more and 80 parts by weight or less relative to 100 parts by weight of the total of said methylcyclohexane and said ethanol.

3. 2. The resin composition for a ceramic green sheet according to claim 1, wherein, relative to a total of 100 parts by weight of the methylcyclohexane and the ethanol, a content of the methylcyclohexane is 20 parts by weight or more and 80 parts by weight or less; when the mixed solvent contains the isopropanol, a content of the isopropanol is 0.4 parts by weight or more and 40 parts by weight or less; when the mixed solvent contains the methyl ethyl ketone, a content of the methyl ethyl ketone is 0.4 parts by weight or more and 40 parts by weight or less; when the mixed solvent contains the methyl propyl ketone, a content of the methyl propyl ketone is 0.4 parts by weight or more and 40 parts by weight or less; and when the mixed solvent contains the methyl isobutyl ketone, a content of the methyl isobutyl ketone is 0.4 parts by weight or more and 40 parts by weight or less.

4. The resin composition for a ceramic green sheet according to claim 1 , wherein the mixed solvent further contains toluene.

5. The resin composition for a ceramic green sheet according to claim 2 , wherein the mixed solvent further contains toluene.

6. The resin composition for a ceramic green sheet according to claim 3 , wherein the mixed solvent further contains toluene.

7. 2. The resin composition for a ceramic green sheet according to claim 1, wherein the mixed solvent does not contain toluene.

8. A method for producing a ceramic green sheet, comprising a step of forming the resin composition for a ceramic green sheet according to any one of claims 1 to 7 into a sheet.

9. A step of producing a ceramic green sheet by forming the resin composition for a ceramic green sheet according to any one of claims 1 to 7 into a sheet; forming an internal electrode pattern on the ceramic green sheet; a step of laminating a plurality of the ceramic green sheets on which the internal electrode patterns are formed to form a laminate; and firing the laminate to produce a ceramic sintered body having a structure in which internal electrode layers are laminated with ceramic layers interposed therebetween.

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