Dielectric ceramic electronic component

Abstract

To provide a dielectric ceramic electronic component in which defective appearance on the surface of a ceramic sintered body can be detected easily.SOLUTION: The dielectric ceramic electronic part 2 has a ceramic sintered body in which at least a part of the surfaces 4b and 4c is composed of a dielectric. The chroma C * value of the base color on the surface of the ceramic sintered body 2 is in the range of 5 to 11, and the lightness L * value is in the range of 38 to 50.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a dielectric ceramic electronic component. [Background technology]

[0002] One example of a known dielectric ceramic electronic component is a multilayer ceramic capacitor, as shown in Patent Document 1 below. When manufacturing this type of multilayer ceramic capacitor, it is necessary to simultaneously fire the dielectric material and the electrode material. Therefore, depending on the manufacturing conditions, cracks may occur on the surface of the sintered ceramic body due to differences in the linear expansion coefficients of these materials, and multilayer ceramic capacitors with cracks must be rejected as defective.

[0003] In addition to cracks, the surface of the ceramic sintered body may have other appearance defects that occur during the manufacturing process, such as scratches or foreign matter adhesion. These appearance defects can be detected by capturing an image using an imaging camera or the like, but the inventors' experiments have revealed that it may be difficult to accurately detect defects depending on the material of the ceramic sintered body and the manufacturing conditions. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-14940 Summary of the Invention [Problem to be solved by the invention]

[0005] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a dielectric ceramic electronic component in which defects in the appearance of the surface of the ceramic sintered body can be easily detected. [Means for solving the problem]

[0006] In order to achieve the above object, a dielectric ceramic electronic component according to one aspect of the present invention comprises: A dielectric ceramic electronic component having a ceramic sintered body at least part of the surface of which is made of a dielectric material, The saturation C of the base color on the surface of the ceramic sintered body * Values ​​are in the range of 5 to 11, and the lightness L * The value is in the range of 38 to 50.

[0007] By ensuring that the saturation and brightness of the base color on the surface of the ceramic sintered body are within the above-mentioned ranges, it becomes easier to detect appearance defects such as cracks, scratches, or foreign matter on the surface of the sintered body. For example, the surface of a dielectric ceramic sintered body having a composition of (CaSr)(TiZr)O3 + minor components (e.g., MnCO3, Al2O3, or SiO2) generally has a gray base color, which makes it difficult to detect cracks, scratches, or foreign matter. In a dielectric ceramic electronic component according to one embodiment of the present invention, the saturation and brightness of the base color can be controlled within the above-mentioned ranges by adjusting the content ratios of V and Mn, etc., and the manufacturing conditions. As a result, it becomes easier to detect appearance defects such as cracks, scratches, or foreign matter on the surface of the sintered body.

[0008] Preferably, the surface roughness Ra of the surface of the ceramic sintered body is within the range of 0.07 to 0.56.

[0009] The ceramic sintered body may have an interior in which electrode layers and dielectric layers are alternately stacked, and the surface of the ceramic sintered body may have a pair of main surfaces facing each other along the stacking direction of the electrode layers and side surfaces intersecting the main surfaces at an angle approximately perpendicular to the main surfaces. In this case, the lightness L of the base color on the main surfaces may be * The value is in the range of 40 to 50, and the lightness L of the base color on the side surface * It is preferable that the value is in the range of 38 to 48. In addition, the saturation C of the base color on the main surface * The value is in the range of 8 to 11, and the saturation C of the base color on the side surface * The value is preferably in the range of 8-10.

[0010] Even if the main surface and the side surface are made of the same dielectric material and are manufactured using the same method, the preferred ranges of lightness and chroma may be slightly different. * The value is the lightness L of the base color on the side surface. * The saturation C of the base color on the main surface is equal to or greater than the value * The value is the saturation C of the base color at the side * tend to be equal to or greater than the value. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 1 is a schematic perspective view of a dielectric ceramic electronic component according to one embodiment of the present invention. [Figure 2A] FIG. 2A is a schematic cross-sectional view of the dielectric ceramic electronic component taken along line IIA-IIA shown in FIG. [Figure 2B] FIG. 2B is a schematic cross-sectional view of the dielectric ceramic electronic component taken along line IIB-IIB shown in FIG. [Figure 3] FIG. 3 is a schematic diagram showing the relationship between the lightness and saturation of the base color. DETAILED DESCRIPTION OF THE INVENTION

[0012] The following describes the embodiments.

[0013] As shown in FIG. 1, a multilayer ceramic capacitor 1, which is an example of a dielectric ceramic electronic component according to an embodiment, has an element body 4 made of a ceramic sintered body having a substantially rectangular parallelepiped (substantially hexahedral) shape.

[0014] The element body 4 has a pair of end faces 4a substantially perpendicular to the X-axis, a pair of main faces 4b substantially perpendicular to the Z-axis, and a pair of side faces 4c substantially perpendicular to the Y-axis. The dimensions of the element body 4 are not particularly limited and may be set to appropriate dimensions depending on the application. For example, the length in the X-axis direction may be 0.3 mm to 5.7 mm, the width in the Y-axis direction may be 0.3 mm to 5.0 mm, and the height in the Z-axis direction may be 0.3 mm to 3.0 mm. In this embodiment, the X-axis, Y-axis, and Z-axis are perpendicular to each other. An external electrode 6 is formed on each of the end faces 4a located on opposite sides of the element body 4 along the X-axis.

[0015] 2A and 2B, the element body 4 is a dielectric ceramic sintered body consisting of a laminate including alternately stacked inner dielectric layers 2 and internal electrode layers 3. The multiple internal electrode layers 3 are stacked so that one end of each layer is alternately exposed to one of the two end faces 4a of the element body 4.

[0016] In this embodiment, the end of the internal electrode layer 3 that is drawn out to the end surface 4a is referred to as the drawn portion 3a. The exposed end of this drawn portion 3a is electrically connected to the external electrode 6 that covers the end surface 4a, and the multiple internal electrode layers 3 are stacked so that they have alternately different polarities along the stacking direction. With this configuration, the internal electrode layers 3 and the external electrodes 6 form a capacitor circuit.

[0017] Each of the external electrodes 6 covers one end face 4a and is formed to extend from the end face 4a across a portion of the main face 4b and side face 4c, and the pair of external electrodes 6 are electrically insulated from each other. The external electrodes 6 only need to be electrically conductive, and there are no particular restrictions on their material or thickness. The external electrodes 6 may be formed of a single layer or multiple layers. For example, the external electrodes 6 may be formed as multi-layer electrodes consisting of baked electrodes (sintered electrodes), resin electrodes, and plated layers.

[0018] 2B, inside the element body 4, outer dielectric layers 2a are laminated on both sides along the Z axis of the laminate of the inner dielectric layers 2 and the internal electrode layers 3. Also, inside the element body 4, margin portions 2b are formed on both sides along the Y axis of the laminate of the inner dielectric layers 2 and the internal electrode layers 3.

[0019] In this embodiment, the outer dielectric layer 2a is made of the same or a different dielectric material as the inner dielectric layer 2, and the outer surface of the outer dielectric layer 2a forms the main surface 4b of the element body 4. In addition, the margin portion 2b is made of the same or a different dielectric material as the inner dielectric layer 2, and the outer surface of the margin portion 2b forms the side surface 4c of the element body 4.

[0020] In this embodiment, the number of laminations of the inner dielectric layers 2 is not particularly limited, but may be, for example, 20 or more, or 50 or more. The number of laminations of the internal electrode layers 3 is determined according to the number of laminations of the inner dielectric layers 2. The average thickness of the inner dielectric layers 2 is also not particularly limited, but may be, for example, 0.5 μm to 100 μm, or 10 μm or less, 5 μm or less, 2.5 μm or less, or 1 μm or less. The average thickness of the internal electrode layers 3 is also not particularly limited, but may be, for example, 0.5 μm to 10 μm, or 5 μm or less, 2.5 μm or less, or 1 μm or less.

[0021] The dielectrics constituting the inner dielectric layer 2, the outer dielectric layer 2a and the margin portion 2b may be the same or different, but in this embodiment they are made of a dielectric composition containing a predetermined subcomponent.

[0022] The main component of the dielectric composition may be a paraelectric or a ferroelectric, such as a dielectric ceramic having a perovskite crystal structure or a dielectric ceramic having a tungsten bronze crystal structure. Examples of dielectric ceramics with a perovskite structure include (Ba,Ca)(Ti,Zr)O3 (e.g., barium titanate), (Ca,Sr)(Ti,Zr)O3 (e.g., calcium titanate and strontium titanate), (K,Na)NbO3, and (Bi,Na)TiO3. Examples of dielectric ceramics with a tungsten bronze structure include Ba(Nb,Ta)2O6, Ca(Nb,Ta)2O6, and (K,Na)Sr2Nb5O. 15 , Ba3TiNb4O 15 ,Ba2LaTi2Nb3O 15 Examples include:

[0023] Preferably, the main component of the dielectric contains Ca and / or Sr and Zr, and more preferably contains a perovskite-type compound represented by the formula ABO3. Here, the main component refers to a component in which the total of the elements constituting the main component is 80 molar parts or more when the total of the elements constituting the dielectric is 100 molar parts. In this embodiment, the perovskite-type compound preferably contains at least Ca and Sr in the A site, and is represented by the composition formula (Ca 1-x Sr x ) m (Zr 1-y-z Ti y Hf z )O3 (hereinafter referred to as a CSZT-based compound). In the above composition formula, the symbols x, y, z, and m each represent an element ratio, and the element ratio is not particularly limited and can be set within a known range.

[0024] For example, m indicates the element ratio of the A site to the B site, and can generally be in the range of 0.9 to 1.1. Also, x indicates the element ratio of Sr occupying the A site, and can be 0≦x≦1. In other words, the ratio of Ca to Sr is arbitrary, and only one of them may be contained.

[0025] y represents the element ratio of Ti in the B site, and z represents the element ratio of Hf in the B site. That is, 1-yz represents the element ratio of Zr in the B site. In this embodiment, it is preferable that 0.80≦1-yz≦1.0. When the element ratio of Zr is within the above range, the high-temperature loaded life under high voltage is improved, and the crack occurrence rate can be further suppressed.

[0026] The element ratio of oxygen (O) in the above composition formula may deviate slightly from the stoichiometric composition.

[0027] In addition to the above-mentioned main components, the dielectric may contain auxiliary components, such as Mn compounds, V compounds, Cr compounds, Si compounds, Al compounds, Mg compounds, Ni compounds, Li compounds, and B compounds, and the types, combinations, and amounts of the auxiliary components are not particularly limited.

[0028] The internal electrode layers 3 function as part of the capacitor circuit to apply a voltage to each inner dielectric layer 2. Therefore, the internal electrode layers 3 are configured to contain a conductive material. Specifically, the conductive material of the internal electrode layers 3 can be made of base metals such as Cu and Ni, precious metals such as Ag, Pd, Au, and Pt, or an alloy containing at least one of these metal elements. More preferably, the conductive material constituting the internal electrode layers 3 is Ni or a Ni-based alloy, since the constituent material of the inner dielectric layer 2 is resistant to reduction. When a Ni-based alloy is used as the conductive material, it is preferable that the Ni-based alloy contains one or more subcomponents selected from Mn, Cr, Co, and Al. In addition, the Ni content in the Ni-based alloy is preferably 95 wt% or more.

[0029] In addition to the conductive material, the internal electrode layer 3 may contain, as a co-material, the ceramic component contained in the inner dielectric layer 2. Also, trace amounts (for example, 0.1 wt% or less) of non-metallic components such as S and P may be contained.

[0030] In this embodiment, the saturation C of the base color of the main surface 4b and the side surface 4c of the element body 4 made of a dielectric ceramic sintered body is * Values ​​are in the range of 5 to 11, and the lightness L * The value is in the range of 38 to 50. In addition, the saturation C of the base color * Value and Lightness L * The value can be measured based on, for example, JIS Z 8781-6:2017. * Value and saturation C * FIG. 1 is a schematic diagram showing an example of the relationship between the value of lightness L * The higher the value, the lighter the color and the more saturated the color. * The higher the value, the more vivid the color.

[0031] By ensuring that the saturation and brightness of the base color of the main surface 4b and side surface 4c of the element body 4 are within the above-mentioned ranges, it becomes easier to detect visual defects such as cracks, scratches, or foreign matter on the surface (main surface 4b and side surface 4c) of the element body 4. For example, the surface of a dielectric ceramic sintered body having a composition of (Ca,Sr)(Ti,Zr)O3 + minor components (e.g., MnCO3, Al2O3, or SiO2) generally tends to have a gray base color, which reduces the ability to detect cracks, scratches, and foreign matter. In the dielectric constituting the surface of the element body 4 according to this embodiment, the saturation and brightness of the base color can be controlled within the above-mentioned ranges by adjusting the content ratios of V and Mn, etc., and manufacturing conditions. As a result, it becomes easier to detect visual defects such as cracks, scratches, or foreign matter on the surface of the element body 4.

[0032] The surface roughness Ra of the surface of the element body 4 is preferably within a range of 0.07 to 0.56. The surface roughness Ra can be measured, for example, based on JIS B 0601-2001. By setting the surface roughness Ra of the surface of the element body 4 within a predetermined range, it becomes easier to detect appearance defects such as cracks, scratches, or foreign matter adhesion on the surface of the element body 4. The surface roughness Ra of the surface of the element body 4 can be controlled, for example, by changing the processing time and processing conditions of barrel polishing of the element body 4 before forming the external electrodes 6,6.

[0033] In this embodiment, the preferred range of lightness and the preferred range of saturation may be different between the main surface 4b and the side surface 4c. For example, the lightness L of the base color on the main surface 4b may be different from that on the side surface 4c. * The value is in the range of 40 to 50, and the lightness L of the base color on the side * It is preferable that the value is in the range of 38 to 48. In addition, the saturation C of the base color on the main surface 4b * The value is in the range of 8 to 11, and the saturation C of the base color on side 4c * The value is preferably in the range of 8-10.

[0034] In this embodiment, even if the main surface 4b and the side surface 4c are made of the same dielectric material and are manufactured using the same method, the preferred ranges of lightness and chroma may be slightly different. For example, the lightness L of the base color on the main surface 4b may be slightly different. * The value is the brightness L of the base color on side 4c. * The saturation C of the base color on the main surface 4b is equal to or greater than the value * The value is the saturation C of the base color on side 4c. * tend to be equal to or greater than the value.

[0035] The multilayer ceramic capacitor 1 of this embodiment can be manufactured by preparing a green chip by a printing method or a sheet method using a paste, firing the green chip, and then forming a pair of external electrodes 6 on the resulting laminate. The manufacturing method will be described in detail below.

[0036] First, we will explain the manufacturing process of the element body 4. In the manufacturing process of the element body 4, a dielectric paste that will become the inner dielectric layer 2 and the outer dielectric layer 2a after firing, and an internal electrode paste that will become the internal electrode layer 3 after firing are prepared.

[0037] The dielectric paste is manufactured, for example, by the following method. First, the dielectric raw materials are mixed uniformly by means of wet mixing or the like and dried. Then, a calcined powder is obtained by heat treatment under predetermined conditions. Next, a known organic vehicle or a known aqueous vehicle is added to the calcined powder and kneaded to prepare the dielectric paste.

[0038] The dielectric paste thus obtained is formed into a sheet by a method such as a doctor blade method to obtain a ceramic green sheet. The dielectric paste may contain additives selected from various dispersants, plasticizers, dielectrics, subcomponent compounds, glass frit, etc., as needed.

[0039] The internal electrode paste is prepared by kneading a metal material with a known binder and solvent.

[0040] Next, the internal electrode paste is applied in a predetermined pattern onto the ceramic green sheet by various printing methods such as screen printing or transfer method to form an internal electrode pattern.

[0041] Then, a plurality of ceramic green sheets on which internal electrode patterns have been formed are stacked and pressed in the stacking direction to obtain a mother laminate. At this time, the ceramic green sheets and the internal electrode patterns are stacked so that the ceramic green sheets are positioned on the upper and lower surfaces of the mother laminate in the stacking direction.

[0042] The mother laminate obtained by the above process is cut to a predetermined size by dicing or press-cutting to obtain multiple green chips. If necessary, the green chips may be solidified and dried to remove plasticizers, and after solidification and drying, they may be barrel-polished using a horizontal centrifugal barrel machine or the like. In barrel polishing, the green chips are placed in a barrel container together with media and polishing solution, and the barrel container is subjected to rotational motion or vibration to polish away unnecessary areas such as burrs generated during cutting. After barrel polishing, the green chips are washed with a cleaning solution such as water and dried.

[0043] Next, the green chip obtained above is subjected to a binder removal process and a firing process to obtain the element body 4. The conditions for the binder removal process are not particularly limited and may be appropriately determined depending on the main component composition of the inner dielectric layer 2 and the main component composition of the internal electrode layer 3. For example, the temperature rise rate is preferably 5°C / hour to 300°C / hour, the holding temperature is preferably 180°C to 400°C, and the temperature holding time is preferably 0.5 hours to 24 hours. The binder removal atmosphere is air or a reducing atmosphere.

[0044] The firing conditions are not particularly limited and may be appropriately determined depending on the main component composition of the inner dielectric layer 2 and the main component composition of the internal electrode layer 3. For example, the holding temperature during firing is preferably 1200°C to 1400°C, more preferably 1220°C to 1300°C, the holding time is preferably 0.5 hours to 8 hours, more preferably 1 hour to 3 hours, and the heating rate and cooling rate (temperature drop rate) are preferably 50°C / hour to 500°C / hour. The firing atmosphere is preferably a reducing atmosphere, and the atmospheric gas may be, for example, a humidified mixed gas of N2 and H2. Furthermore, when the internal electrode layer 3 is made of a base metal such as Ni or a Ni-based alloy, the oxygen partial pressure in the firing atmosphere should be 2.0 x 10 -13 atm~1.0×10 -7 It is preferable to use atm.

[0045] After firing, the obtained element body 4 may be subjected to a reoxidation treatment (annealing) as needed. The annealing conditions are preferably, for example, such that the oxygen partial pressure during annealing is higher than the oxygen partial pressure during firing, and the holding temperature is 1150°C or lower.

[0046] In the above-described binder removal treatment, firing treatment, and annealing treatment, a wetter or the like may be used to humidify the N2 gas or mixed gas, and in this case, the water temperature is preferably about 5° C. to 75° C. Furthermore, the binder removal treatment, firing treatment, and annealing treatment may be performed consecutively or independently.

[0047] The end faces of the element body 4 obtained as described above are polished, and an external electrode paste is applied and baked to form the external electrodes 6. Then, if necessary, a coating layer is formed on the surface of the external electrodes 6 by plating or the like.

[0048] Through the above steps, a multilayer ceramic capacitor 1 having external electrodes 6 is obtained. When manufacturing the element body 4, which is a dielectric ceramic sintered body, the saturation and brightness of the base color of the main surface 4b and the side surface 4c are controlled within the aforementioned ranges by adjusting the content ratios of V, Mn, Cr, Ti, etc. and the manufacturing conditions of the element body 4.

[0049] For example, by changing the content ratio of at least one of V, Mn, Cr, and Ti in the dielectric raw material powder, the lightness and saturation can be changed as follows. For example, increasing the amount of V added from the base tends to decrease the lightness value and increase the saturation value. In addition, increasing the amount of Mn added from the base tends to decrease the lightness value and decrease the saturation value. Increasing the amount of Cr added from the base tends to decrease the lightness value and increase the saturation value. Furthermore, increasing the amount of Ti added from the base tends to decrease the lightness value and decrease the saturation value.

[0050] Furthermore, by making the particle size of the dielectric material powder smaller than the reference value, the lightness value tends to decrease, while the saturation value tends to remain unchanged.

[0051] Furthermore, by maintaining the maximum firing temperature for a longer period of time than the standard value when firing the element body to produce it, the lightness value tends to decrease, while the saturation value tends to remain unchanged. Also, by increasing the temperature rise rate up to the maximum firing temperature when firing the element body to produce it, above the standard value, the lightness value tends to increase, while the saturation value tends to remain unchanged. Also, by increasing the temperature during annealing treatment after firing the element body above the standard value, the lightness value tends to remain unchanged, while the saturation value tends to increase.

[0052] In this embodiment, the standard value of the content ratio of at least one of V, Mn, Cr, and Ti is, for example, 0.2 to 1 wt%, and when increasing or decreasing, it is preferable to do so within a range of up to 10% from that standard value. Also, when the standard value of the particle size of the dielectric raw material powder is, for example, d50=0.4 to 0.6 μm, when increasing or decreasing, it is preferable to do so within a range of up to 80% from that standard value.

[0053] The standard value for the duration of time the maximum firing temperature is maintained is, for example, 100 to 130 minutes, and when increasing or decreasing it, it is preferable to keep it within a range of up to 80% of that standard value. The standard value for the temperature rise rate is, for example, 100 to 300 hr / °C, and when increasing or decreasing it, it is preferable to keep it within a range of up to 80% of that standard value. The standard value for the annealing temperature is, for example, 600 to 1000°C, and when increasing or decreasing it, it is preferable to keep it within a range of up to 80% of that standard value.

[0054] By combining these conditions, the saturation and brightness of the base color of the main surface 4b and the side surface 4c can be controlled within the above-mentioned ranges.

[0055] The obtained multilayer ceramic capacitor 1 can be surface-mounted on a substrate such as a printed wiring board using solder (including molten solder, solder cream, and solder paste) or a conductive adhesive, and is used in various electronic devices. Alternatively, the multilayer ceramic capacitor 1 can be mounted on a substrate via wire-like lead terminals or plate-like metal terminals. Alternatively, the multilayer ceramic capacitor 1 can be built into a circuit board.

[0056] The multilayer ceramic capacitor 1 of this embodiment satisfies the C0G characteristics defined in the JIS CH standard, and also has high resistivity and excellent high-temperature accelerated life. In particular, the multilayer ceramic capacitor 1 exhibits excellent insulation characteristics even when exposed to a high-temperature environment of 200°C or higher.

[0057] Furthermore, in the multilayer ceramic capacitor 1 of this embodiment, when an appearance inspection is carried out after production, it becomes easier to detect appearance defects such as cracks, scratches, or foreign matter attached to the surface of the element body.

[0058] The present invention is not limited to the above-described embodiment, and various modifications can be made within the scope of the present invention.

[0059] For example, at least one of the outer layer portions 2a, 2a shown in Figure 2B may be covered with a transparent glass layer. Furthermore, the margin portion 2b does not necessarily have to be made of a dielectric material, and may be made of, for example, a transparent or opaque glass material. Furthermore, the dielectric ceramic electronic component is not limited to the multilayer ceramic capacitor 1, and may be any other electronic component as long as the surface of the ceramic sintered body made of a dielectric material is at least partially visible from the outside. [Example]

[0060] More detailed examples will be described below, but the present invention is not limited to these examples.

[0061] Example 1 First, SrCO3, CaCO3, TiO2, ZrO2, and HfO2 with an average particle size d50 = 0.4 μm were prepared as starting materials for producing dielectric oxides. Next, each of the prepared starting materials was mixed to obtain a final composition of [(Ca 0.7 Sr 0.3 )O〔(Ti 0.03 Zr 0.92 Hf 0.05 The materials were weighed and mixed in a weight ratio such that the pre-calcination mixture was obtained.

[0062] The resulting pre-calcination mixture was then calcined to obtain a dielectric oxide having the above composition. The calcination conditions were as follows: heating rate: 200°C / hour, holding temperature: 1200°C, temperature holding time: 2 hours, atmosphere: air. The resulting dielectric oxide was then pulverized using an alumina roll.

[0063] Next, a mixture of MnO, Al2O3, and SiO2 was prepared as a sintering aid and added to 100 parts by weight of the above dielectric oxide in a predetermined ratio (0.2 wt% for MnO as shown in Table 1A). 4.8 parts by weight of acrylic resin, 40 parts by weight of methylene chloride, 20 parts by weight of ethyl acetate, 6 parts by weight of mineral spirits, and 4 parts by weight of acetone were mixed in a ball mill to form a paste, and a dielectric layer paste was obtained.

[0064] 100 parts by weight of Ni particles with an average particle size of 0.1 to 0.8 μm, 40 parts by weight of an organic vehicle (8 parts by weight of ethyl cellulose dissolved in 92 parts by weight of butyl carbitol), and 10 parts by weight of butyl carbitol were kneaded using a three-roll mill to form a paste, and a paste for the internal electrode layer was obtained.

[0065] 100 parts by weight of Cu particles with an average particle size of 0.5 μm, 35 parts by weight of an organic vehicle (8 parts by weight of ethyl cellulose resin dissolved in 92 parts by weight of butyl carbitol), and 7 parts by weight of butyl carbitol were kneaded to form a paste, and a paste for external electrodes was obtained.

[0066] Next, a green sheet having a thickness of 7 μm was formed on a PET film using the dielectric layer paste, and the internal electrode layer paste was printed thereon, and then the green sheet was peeled off from the PET film.

[0067] Next, these green sheets and exterior green sheets (for outer dielectric layers on which no internal electrode layer paste was printed) were laminated and pressed together to obtain a green chip. The number of layers of sheets with internal electrodes was 101.

[0068] Next, the green chip was cut to a specified size, debindered, fired, and annealed to obtain a multilayer ceramic fired body. As shown in the table, the maximum firing temperature was 1230°C, the holding time was 90 minutes, the heating rate was 400°C / hr, and the annealing temperature was 700°C.

[0069] Next, the end faces of the fired multilayer ceramic body were polished by sandblasting, and then the external electrode paste was transferred to the end faces and fired in a humidified N2+H2 atmosphere at 800°C for 10 minutes to form external electrodes, resulting in a multilayer ceramic capacitor sample. Each sample thus obtained measured 3.2mm x 1.6mm x 0.6mm, with 100 dielectric layers sandwiched between internal electrode layers, each 4.9µm thick, and the internal electrode layer being 0.2µm thick.

[0070] The lightness L of the base color of the main surface 4b and the side surface 4c of the element body 4 of each sample * Value and Saturation C * The values ​​were determined in accordance with JIS Z 8781-6:2017. The measurement location was near the center of one of the main surfaces 4b or side surfaces 4c, and the average value of 10 samples was determined. The results are shown in Table 1B.

[0071] Furthermore, the surface roughness Ra of the main surface 4b and side surface 4c of the sample was determined based on JIS B 0601-2001. The measurement was performed near the center of one main surface 4b or one side surface 4c, and the average value of 10 samples was determined. The results are shown in Table 1B.

[0072] Of the resulting product samples, 1,000 samples with good appearance were prepared. Of these, 100 were subjected to heat treatment or pressure cooker testing (PCT) to induce cracks. In addition, another 100 samples had their chip surfaces scratched with a scriber. Another 100 samples were prepared by sprinkling a small amount of Fe powder on the surface of the green chip and firing them (at 700°C for 1 hour) to prepare samples with foreign matter. The remaining 700 samples were used as samples with good appearance.

[0073] Each sample prepared in this way was visually inspected by the same visual inspector. A detection rate of 95% or higher for cracks, scratches, and foreign matter was rated as "good." The detection rates for each type of defect (cracks, scratches, and foreign matter) are shown in Table 1C.

[0074] Examples 2 to 4 As shown in Table 1A, except that the holding time and / or the temperature rising rate were changed, multilayer ceramic capacitor samples were produced in the same manner as in Example 1, and measurements were carried out in the same manner as in Example 1. The results are shown in Tables 1B and 1C.

[0075] Comparative Examples 1 to 8 As shown in Table 1A, except that the particle size of the dielectric raw material was changed, multilayer ceramic capacitor samples were produced in the same manner as in Examples 1 to 4, and measurements were carried out in the same manner as in Example 1. The results are shown in Tables 1B and 1C.

[0076] Comparative Examples 9 to 11 and Example 5 As shown in Table 1A, except that the particle size of the dielectric raw material was changed and the firing temperature was changed, samples of multilayer ceramic capacitors were produced in the same manner as in Examples 1 to 4, and measurements were carried out in the same manner as in Example 1. The results are shown in Tables 1B and 1C.

[0077] Examples 6 to 9 As shown in Table 1A, except that the particle size of the dielectric raw material was changed and the firing temperature was changed, samples of multilayer ceramic capacitors were produced in the same manner as in Examples 1 to 4, and measurements were carried out in the same manner as in Example 1. The results are shown in Tables 1B and 1C.

[0078] Example 10 and Comparative Examples 12 to 14 As shown in Table 1A, except that the firing temperature was changed, multilayer ceramic capacitor samples were produced in the same manner as in Examples 1 to 4, and measurements were carried out in the same manner as in Example 1. The results are shown in Tables 1B and 1C.

[0079] Examples 11 to 14 As shown in Table 1A, except that the particle size of the dielectric raw material was changed and the firing temperature was changed, samples of multilayer ceramic capacitors were produced in the same manner as in Examples 1 to 4, and measurements were carried out in the same manner as in Example 1. The results are shown in Tables 1B and 1C.

[0080] Example 15 and Comparative Examples 15 to 17 As shown in Table 1A, except that the particle size of the dielectric raw material was changed and the firing temperature was changed, samples of multilayer ceramic capacitors were produced in the same manner as in Examples 1 to 4, and measurements were carried out in the same manner as in Example 1. The results are shown in Tables 1B and 1C.

[0081] Comparative Examples 19 to 21 As shown in Table 1A, except that the firing temperature was changed, multilayer ceramic capacitor samples were produced in the same manner as in Examples 1 to 4, and measurements were carried out in the same manner as in Example 1. The results are shown in Tables 1B and 1C.

[0082] Example 16, Comparative Examples 22 to 27 As shown in Table 2A, except that V was ignited, the amount of Mn added was changed, and the annealing temperature was changed, multilayer ceramic capacitor samples were produced in the same manner as in Examples 2, 7, or 12, and measurements were performed in the same manner as in Example 1. The results are shown in Tables 2B and 2C.

[0083] Examples 17 and 18 Except for the fact that the element body was sandblasted before the external electrodes were formed, and the surface roughness of the main surface 4b and the side surface 4c was adjusted to the values ​​shown in Table 3B, a multilayer ceramic capacitor sample was produced in the same manner as in Example 2, and measurements were carried out in the same manner as in Example 1. The results are shown in Tables 3B and 3C.

[0084] Rating 1 From the results shown in Tables 1A to 1C and Tables 2A to 2C, the saturation C * and brightness L * It was found that in each of the examples where the saturation C of the main surface satisfies the predetermined range, the detection rate for cracks, scratches, and foreign matter is improved to 96% or more compared to the comparative examples. * is preferably in the range of 8 to 11, and the lightness L * is preferably in the range of 40 to 50, and the saturation C * is preferably in the range of 8 to 10, and the lightness L * It was found that it is preferable that the value is in the range of 38 to 48.

[0085] Rating 2 The results shown in Tables 3A to 3C indicate that the surface roughness of the front and side surfaces may be in the range of 0.07 to 0.56, and the results shown in Tables 1A to 2C indicate that the surface roughness may be in the range of 0.14 to 0.47.

[0086] [Table 1A]

[0087] [Table 1B]

[0088] [Table 1C]

[0089] [Table 2A]

[0090] [Table 2B]

[0091] [Table 2C]

[0092] [Table 3A]

[0093] [Table 3B]

[0094] [Table 3C] [Explanation of symbols]

[0095] 1. Multilayer ceramic capacitors (dielectric ceramic electronic components) 2... Inner dielectric layer 2a... Outer dielectric layer 2b... Margin 3… Internal electrode layer 4... Element body (sintered ceramic body) 4a… End face 4b... Main surface 4c… Side 6... External electrode

Claims

1. A dielectric ceramic electronic component having a ceramic sintered body at least part of the surface of which is made of a dielectric material, The saturation C of the base color on the surface of the ceramic sintered body * The value is in the range of 5 to 11, and the lightness L * Dielectric ceramic electronic components with a value in the range of 38 to 50.

2. 2. The dielectric ceramic electronic component according to claim 1, wherein the surface roughness Ra of the surface of the ceramic sintered body is in the range of 0.07 to 0.

56.

3. Electrode layers and dielectric layers are alternately stacked inside the ceramic sintered body, a surface of the ceramic sintered body having a pair of main surfaces facing each other along a stacking direction of the electrode layers and a side surface intersecting the main surfaces at an angle substantially perpendicular to the main surfaces; The lightness L of the base color on the main surface * The value is in the range of 40 to 50, and the lightness L * The value is in the range of 38 to 48, The saturation C of the base color on the main surface * The value is in the range of 8 to 11, and the saturation C of the base color at the side * 3. The dielectric ceramic electronic component according to claim 1, wherein the value is in the range of 8 to 10.

4. Electrode layers and dielectric layers are alternately stacked inside the ceramic sintered body, a surface of the ceramic sintered body having a pair of main surfaces facing each other along a stacking direction of the electrode layers and a side surface intersecting the main surfaces at an angle substantially perpendicular to the main surfaces; The lightness L of the base color on the main surface * The value is the lightness L of the base color on the side surface. * is equal to or greater than the value, The saturation C of the base color on the main surface * The value is the saturation C of the base color on the side surface. * 3. The dielectric ceramic electronic component according to claim 1, wherein the value is equal to or greater than the above.

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