JP2005126505A - Ink for gravure printing, and method for manufacturing laminated ceramic electronic component - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a conductor pattern having good smoothness without producing structural defects in the conductor pattern even when a ceramic raw material ink is used for gravure printing on a section of a ceramic green sheet where the conductor pattern is not formed. <P>SOLUTION: The conductive ink for gravure printing comprises a conductive powder such as a Ni powder, an organic vehicle and a binder resin, wherein the binder resin comprises an ethyl cellulose resin and 0.5-10 wt% of a low-molecular weight resin having an average molecular weight of 300-5,000, such as a terpene resin. In a conductor pattern-forming step 9, a conductive ink prepared in a conductive ink-preparing step 6 is used to apply gravure printing to a ceramic sheet to form the conductive pattern. In a dielectric coating film-forming step 10, a dielectric ink prepared in a dielectric ink-preparing step 8 is used to apply gravure printing to a section of a ceramic sheet where the conductor pattern is not formed to form a dielectric coating film. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  TECHNICAL FIELD The present invention relates to a gravure printing ink and a multilayer ceramic electronic component, and more specifically, a gravure conductive ink used for forming an internal electrode of a multilayer ceramic electronic component, and the conductive ink manufactured using the conductive ink. The present invention relates to a multilayer ceramic electronic component.

  In recent years, with the miniaturization of various electronic devices typified by mobile phones, multilayer ceramic electronic components mounted on these electronic devices are desired to be further thinned, downsized and reduced in cost.

  For example, in a multilayer ceramic capacitor, the thickness of the dielectric ceramic layer is reduced to 5 μm or less in order to realize a large capacity, and the number of laminated dielectric ceramic layers is also increased to 300 or more. .

  In addition, as a conductive material used for the internal electrode, a base metal material such as Ni or Cu is used instead of a noble metal material such as Ag or Pd, thereby reducing the cost. The pulverization of conductive materials is also progressing.

  As this type of conventional technology, an internal electrode forming ink containing a tackifier is screen printed on a base film and dried to form an electrode, and then a ceramic slurry is applied to the base film and dried. A ceramic green sheet in which electrodes are embedded on the base film (hereinafter referred to as “ceramic sheet”) is produced, and the ceramic sheet is transferred onto another ceramic sheet or electrode, thereby producing a multilayer ceramic electronic component. The technique which performs is known (patent document 1).

  In recent years, gravure printing capable of high-speed printing and capable of forming internal electrodes at low cost has been actively developed. For example, for 100 parts by weight of base metal powder containing nickel as a main component, A gravure electrode ink has been proposed in which binder resin such as ethyl cellulose resin and butyral resin is 1 to 15 parts by weight, organic solvent is 20 to 150 parts by weight, viscosity is 1 Pa · s or less, and aggregates of 10 μm or more are removed. (Patent Document 2).

  In Patent Document 2, an attempt is made to ensure printing suitability in gravure printing by making the ink viscosity low and preventing the occurrence of thixotropy.

  That is, in screen printing, a high-viscosity conductive paste having thixotropic properties (high viscosity before printing, low viscosity during printing, and high viscosity after printing) is required to prevent bleeding during printing. However, in gravure printing, when the ink viscosity becomes a high viscosity of 1.0 Pa · s or more, the conductive ink does not transfer from the concave portion formed on the surface of the gravure roll to the substrate to be printed, resulting in poor printing. Moreover, if the thixotropic property of the conductive ink is strong, transfer from the gravure roll to the printing medium is insufficient, and printing unevenness such as blurring may occur. For this reason, in gravure printing, a conductive ink having a low viscosity of 1.0 Pa · s or less and a suppressed thixotropy is required.

  Therefore, in Patent Document 2, a conductive ink for gravure printing that has a low viscosity and prevents thixotropy is realized, thereby attempting to ensure printing suitability in gravure printing.

Japanese Patent Laid-Open No. 2-114616 Japanese Patent Laid-Open No. 10-335167

  However, Patent Document 1 attempts to flatten the electrode-embedded ceramic sheet so that the laminate is not distorted by embedding the electrode in the ceramic sheet. Because of its long time and low productivity, it cannot fully cope with multilayer ceramic electronic components that require thinning and multilayering.

  Accordingly, it is considered that the gravure printing method is more suitable than the screen printing method in order to form a high-definition internal electrode capable of high-speed printing at a low cost.

  By the way, in the case of gravure printing, in order to prevent the laminate from being distorted, a ceramic raw material ink mainly composed of a ceramic raw material is separately prepared and applied to portions other than the conductor pattern forming portion on the ceramic sheet. A method has been proposed in which a ceramic raw material ink is gravure-printed to form a ceramic coating film, thereby flattening the ceramic sheet.

  However, when gravure printing is performed on a ceramic sheet using a conventional conductive ink as in Patent Document 2 and a conductor pattern is formed thereby, the conductor pattern is formed using a ceramic raw material ink thereafter. If an attempt is made to perform gravure printing on an unexposed area, the gravure plate of the gravure printing machine comes into contact with the periphery of the conductor pattern and the periphery of the conductor pattern is pressed against the gravure plate, which may cause damage or loss of the conductor pattern. There is. And when ceramic sheets are laminated, pressed and fired in such a state where the conductor pattern is damaged or missing, the electrical characteristics deteriorate, such as a decrease in capacitance due to partial damage or missing of the internal electrode. End up.

  On the other hand, when the amount of binder resin such as ethyl cellulose resin or butyral resin is simply increased to prevent breakage or loss of the conductor pattern, the ink viscosity increases and the ink viscosity exceeds 1.0 Pa · s. As a result, sufficient transferability cannot be obtained, and gravure printing traces (cell traces) are formed on the printed coating film. Can not be.

  The present invention has been made based on such circumstances, and is a gravure printing ink capable of obtaining a printed film excellent in flexibility. More specifically, a ceramic raw material ink is formed into a conductor pattern on a ceramic sheet. A conductive ink for gravure printing that can obtain a conductor pattern having good smoothness without causing structural defects such as breakage or missing in the conductor pattern even if gravure printing is performed on a portion that has not been made, and this An object of the present invention is to provide a multilayer ceramic electronic component using a conductive ink for gravure printing.

  In order to achieve the above object, the present inventors have intensively studied.In addition to the ethyl cellulose resin, the binder resin includes a specific low molecular weight resin such as a terpene resin having a number average molecular weight of 300 to 5,000. Flexibility can be imparted to the printed coating film formed by gravure printing, so that even if the ceramic raw material ink is gravure printed on the part where the conductor pattern is not formed, the conductor pattern is damaged or missing. The knowledge that it was possible to avoid the occurrence of defects was obtained.

  The present invention has been made based on such knowledge, gravure printing ink according to the present invention is a gravure printing ink containing at least an inorganic powder, a binder resin, and an organic solvent, The binder resin is an ethyl cellulose resin and has a number average molecular weight of 300 to 5,000 and at least selected from terpene resin, terpene phenol resin, petroleum resin, polybutadiene resin, polyisoprene resin, and polyether resin. One low molecular weight resin, and the content of the low molecular weight resin is 0.5 to 10% by weight.

  In addition, the gravure printing ink of the present invention is a conductive ink for gravure printing (hereinafter simply referred to as “conductive ink”), which is the inorganic powder or the conductive powder, and the ink is a conductive ink. It is characterized by.

  The conductive ink of the present invention is characterized in that the conductive powder is nickel powder.

  In addition, the method for producing a multilayer ceramic electronic component according to the present invention includes a conductive ink production step for producing the gravure printing ink described above, and gravure printing is performed on the ceramic sheet using the conductive ink. A conductive pattern forming step for forming a ceramic raw material ink for preparing a ceramic raw material ink mainly composed of a ceramic raw material, and the ceramic raw material ink for the ceramic sheet on which the conductive pattern is formed, using the ceramic raw material ink Gravure printing is applied to the part where the conductor pattern is not formed, and a ceramic coating film forming process for forming a ceramic coating film, and a laminate is formed by laminating a plurality of ceramic sheets on which the conductor pattern and the ceramic coating film are formed. And a firing process for firing the laminate. It is characterized in that.

  In the method for manufacturing a multilayer ceramic electronic component according to the present invention, the ceramic raw material is a dielectric material.

  According to the gravure printing ink of the present invention, a printed coating film excellent in flexibility can be obtained. Specifically, since the binder resin contains an ethyl cellulose resin and a specific low molecular weight resin such as a terpene resin, and the content of the low molecular weight resin is 0.5 to 10% by weight, the binder resin is formed by gravure printing. Flexibility can be imparted to the printed coating film, so that even if the ceramic raw material ink is gravure-printed on the part where the conductive pattern (printed coating film) is not formed, structural defects such as breakage or missing of the conductive pattern are present. It can be avoided.

  In addition, since the low molecular weight resin has a number average molecular weight of 300 to 5,000, it is sufficiently smaller than the number average molecular weight (about 32000) of the ethyl cellulose resin and can suppress an increase in the viscosity of the conductive ink. The desired gravure printing can be realized without impairing the image quality.

  In addition, since the manufacturing method of the multilayer ceramic electronic component of the present invention is manufactured using the above conductive ink, the internal electrode has good flatness without causing any structural defects such as breakage or missing in the internal electrode. It is possible to easily manufacture a multilayer ceramic electronic component such as a multilayer ceramic capacitor having excellent reliability with high efficiency.

  Next, an embodiment of the present invention will be described in detail.

  As an embodiment of the present invention, a case where the gravure printing ink is a conductive ink will be described. The conductive ink of the present invention contains at least a conductive powder, a binder resin, and an organic solvent, and the binder resin is an ethyl cellulose resin and has a number average molecular weight of 300 to 5,000, and is a terpene resin or terpene phenol type. Resin, petroleum resin, polybutadiene resin, polyisoprene resin, and at least one low molecular weight resin selected from polyether resins, and the content of the low molecular weight resin is 0.5 to 10% by weight.

  In addition to the ethyl cellulose resin as the binder resin, a specific low molecular weight resin such as a terpene resin having a number average molecular weight of 300 to 5000 is contained in an amount of 0.5 to 10% by weight. When a conductive pattern is formed by gravure printing, flexibility is imparted to the printed coating film that is a conductor pattern, and as a result, even if the ceramic raw material ink is gravure printed on a part other than the conductive pattern formation part on the ceramic sheet It is possible to avoid the occurrence of structural defects such as breakage or missing in the conductor pattern.

  Here, the reason why the number average molecular weight of the low molecular weight resin is set to 300 to 5,000 is as follows.

  That is, by using a low molecular weight resin as the binder resin, it is possible to impart flexibility to the conductor pattern that is a printed coating film, but even if a low molecular weight resin having a number average molecular weight of less than 300 is included. In addition, since the number average molecular weight is too small, sufficient flexibility cannot be imparted to the printed coating film, and when the ceramic raw material ink is gravure-printed on a portion other than the conductor pattern forming portion, the gravure plate is formed on the peripheral portion of the conductor pattern. If pressed, structural defects such as breakage or missing of the conductor pattern may occur.

  On the other hand, if the number average molecular weight exceeds 5,000, the number average molecular weight increases and approaches the number average molecular weight (about 32000) of the ethyl cellulose resin, resulting in an increase in viscosity and ensuring sufficient transferability even when gravure printing is performed. Cannot be performed, and there is a risk that the shape of the printed coating film may be abnormal.

  Therefore, in the present conductive ink, the number average molecular weight of the low molecular weight resin added together with the ethyl cellulose resin is limited to 300 to 5000 as the binder resin.

  The reason why the content of the low molecular weight resin is 0.5 to 10% by weight is as follows.

  That is, by including the low molecular weight resin in the conductive ink, flexibility can be imparted to the conductor pattern as the printed coating film as described above, but the content of the low molecular weight resin is 0.5% by weight. If it is less than%, the effect of imparting flexibility to the printed coating film cannot be exhibited sufficiently. On the other hand, if the content of the low molecular weight resin exceeds 10% by weight, the viscosity increases, and even if gravure printing is performed, sufficient transferability cannot be ensured, and the shape of the printed coating film may be abnormal. There is.

  Therefore, in the present conductive ink, the content of the low molecular weight resin is set to 0.5 to 10% by weight.

  Next, a method for producing the conductive ink will be described in detail.

  First, a predetermined amount of conductive powder such as Ni and Cu, an organic solvent such as terpineol and ethylbenzene, and a dispersing agent as required, are weighed and mixed with a grinding medium such as cobblestone into a resin pot. Then, the resin pot is rotated at a constant speed for a predetermined time to perform dispersion treatment, thereby producing a first slurry.

  Next, at least one low molecular weight resin selected from terpene resins, terpene phenol resins, petroleum resins, polybutadiene resins, polyisoprene resins, and polyether resins having a number average molecular weight of 300 to 5,000 is used. An organic vehicle is prepared by weighing the conductive ink so that the content in the conductive ink is 0.5 to 10% by weight, and mixing the low molecular weight resin and the ethyl cellulose resin with an organic solvent. The ethyl cellulose resin is preferably weighed so that the content in the conductive ink is 1 to 10% by weight.

  Next, an organic solvent having the same composition as the organic solvent contained in the first slurry and the organic vehicle are added to the first slurry in the resin pot, and the resin pot is added at a constant speed for a predetermined time. Rotate and disperse to produce a second slurry, and then perform a predetermined pressure filtration process to produce a conductive ink.

  Next, a multilayer ceramic capacitor as a multilayer ceramic electronic component manufactured using the conductive ink will be described in detail.

  FIG. 1 is a cross-sectional view schematically showing an embodiment of the multilayer ceramic capacitor.

In the multilayer ceramic capacitor, internal electrodes (internal conductors) 2 (2a to 2f) and a dielectric layer 3 (3a to 3f) are embedded in a ceramic sintered body 1 made of a dielectric material mainly composed of BaTiO _3. At the same time, external electrodes 4a and 4b are formed on both ends of the ceramic sintered body 1, and plating films 5a and 5b are formed on the surfaces of the external electrodes 4a and 4b.

  The internal electrodes 2a to 2f are juxtaposed in the stacking direction, the internal electrodes 2a, 2c, and 2e are electrically connected to the external electrode 4a, and the internal electrodes 2b, 2d, and 2f are electrically connected to the external electrode 4b. And an electrostatic capacity is formed between the opposing surfaces of the internal electrodes 2a, 2c, and 2e and the internal electrodes 2b, 2d, and 2f.

  Next, a method for manufacturing the multilayer ceramic capacitor will be described.

  FIG. 2 is a manufacturing process diagram showing an embodiment of a method for manufacturing a multilayer ceramic capacitor.

  First, in the conductive ink preparation step 6, a conductive ink is prepared by the method described above.

Next, in ceramic sheet manufacturing step 7, the ceramic slurry prepared so that the molar ratio Ba / Ti of Ba and Ti is a predetermined ratio is subjected to a molding process by a doctor blade method or the like, and polyethylene terephthalate (PET) or the like. A ceramic sheet mainly composed of BaTiO ₃ is prepared on the base film.

In addition, in the dielectric material ink production process (ceramic raw material ink production process) 8, a crushing medium such as cobblestone, a dispersant, an organic solvent, and a plasticizer are put into a resin pot and sufficiently mixed, and fine powder is added to this mixed solution. A dielectric powder (ceramic raw material powder) such as BaTiO ₃ is added, and a resin pot is rotated at a constant speed for a predetermined time to perform dispersion treatment, thereby producing a dielectric material ink (ceramic raw material ink).

  Next, the process proceeds to a conductor pattern forming step 9 where gravure printing is performed on the ceramic sheet using the conductive ink to form a conductor pattern on the ceramic sheet.

  In the subsequent dielectric coating film forming process (ceramic coating film forming process) 10, the dielectric material ink prepared in the dielectric material ink manufacturing process 8 is used, and gravure printing is performed on the portion where the conductor pattern is not formed. A film (ceramic coating) is formed.

  Subsequently, it progresses to the laminated body preparation process 11, the ceramic sheet | seat in which the conductor pattern and the dielectric coating film were formed on the surface is laminated | stacked, and a laminated body is formed.

  FIG. 3 is a perspective view schematically showing the configuration of the laminate.

  On the surface of the ceramic sheets 15a to 15f, the conductor patterns 16a to 16f are formed in a strip shape from one end surface so that one end forms an electrode extraction portion, and in portions where the conductor patterns 16a to 16f are not formed. Dielectric coating films 17a to 17f are formed. Then, the ceramic sheets are laminated so that the electrode extraction portions are staggered, and then the laminated ceramic sheets are sandwiched between a pair of ceramic sheets 18 and 19 on which a conductor pattern and a dielectric coating film are not formed, and are crimped. A laminate is formed.

  Next, returning to FIG. 2, in the firing step 12, the laminated body is cut to a predetermined size, and then subjected to a firing treatment at a predetermined temperature, and the ceramic sintered in which the internal electrode (internal conductor) 2 and the dielectric layer 3 are embedded. The body 1 is produced.

  In the external electrode forming step 13, a conductive paste containing conductive particles such as Cu is used, and the conductive paste is applied to both ends of the ceramic sintered body 1, and then subjected to a baking treatment to provide external electrodes. 4a and 4b, and then, in the plating step 14, electroless plating or electrolytic plating is appropriately performed to produce plated films 5a and 5b made of Sn, Ni, solder, etc. on the surfaces of the external electrodes 4a and 4b. Thus, a multilayer ceramic capacitor is manufactured.

  As described above, since the multilayer ceramic capacitor is manufactured using the conductive ink, there is no structural defect such as breakage or missing in the internal electrode, and the reliability having the internal electrode with good flatness is achieved. Can be manufactured easily with high efficiency.

  The present invention is not limited to the above embodiment. In the present embodiment, a multilayer ceramic capacitor has been described as an example of a multilayer ceramic electronic component. However, the present invention can be applied to multilayer ceramic electronic components such as a multilayer ceramic inductor, a multilayer ceramic LC component, and a multilayer ceramic substrate. Absent.

  In the above embodiment, the conductive ink and the dielectric material ink are formed on the ceramic sheet. However, the dielectric material ink is not necessarily provided.

  In the above embodiment, the case where the gravure printing ink is a conductive ink has been described. However, the gravure printing ink of the present invention is not limited to the conductive ink. For example, for all gravure printing inks containing inorganic powder such as ceramic raw material powder as well as conductive powder, it is possible to achieve an effect of forming a printed coating film having flexibility and excellent strength.

Next, examples of the present invention will be specifically described.

Ni powder having an average particle size of 0.5 μm: 50% by weight, modified polyacrylate (dispersant): 2% by weight, terpineol (organic solvent): 23% by weight Ni powder, modified polyacrylate, Turpineol was weighed. Then, these weighed materials were put into a resin pot having a volume of 1.0 × 10 ⁻³ m ³ together with a boulder having a diameter of 5 mm and prepared. Next, this resin pot was rotated at a rotational speed of 2.5 s ⁻¹ (150 rpm) for 12 hours to perform dispersion treatment, thereby producing a first slurry.

次に、混合樹脂：５重量％、ターピネオール：２０重量％となるように有機ビヒクルを調製した後、樹脂製ポット中の第１のスラリーに前記有機ビヒクルを添加し、樹脂製ポットを回転速度回転速度２．５ｓ^−１（１５０rpm）で１２時間回転させて分散処理し、第２のスラリーを作製した。 Next, an ethyl cellulose resin having a number average molecular weight of 32000 is used as the first binder resin, and a low molecular weight resin having a number average molecular weight of 260 to 5000 shown in Table 1 is used as the second binder resin, and the content in the conductive ink is Weighing so as to be in Table 1 to prepare a mixed resin.

Next, an organic vehicle was prepared so that the mixed resin was 5% by weight and the terpineol was 20% by weight, and then the organic vehicle was added to the first slurry in the resin pot, and the resin pot was rotated at a rotational speed. The dispersion was carried out by rotating at a speed of 2.5 s ⁻¹ (150 rpm) for 12 hours to prepare a second slurry.

Next, the second slurry was subjected to a pressure of 1.47 × 10 ⁵ Pa (1) using a membrane filter having openings of 20 μm, 10 μm, 5 μm, 3 μm, and 1.0 μm (twice the average particle diameter of Ni powder). The lump was removed by pressure filtration of less than 5 kg / cm ² ) to prepare conductive inks of sample numbers 3 to 10.

  Further, as a comparative example, conductive inks of Sample Nos. 1 and 2 that did not contain the second binder resin and contained only the first binder resin (ethyl cellulose resin) as a binder component were prepared.

Next, for each of sample numbers 1 to 10, the ink viscosity at a shear rate of 10 s ⁻¹ was measured at 25 ± 0.5 ° C. with a rotary viscometer.

  Next, a dielectric material ink was prepared, and a conductor pattern and a dielectric coating film were formed on the ceramic sheet.

That is, first, polyvinyl butyral resin (dispersant), terpineol, and dioctyl phthalate (plasticizer) are mixed with a cobblestone having a diameter of 5 mm in a resin pot having a volume of 1.0 × 10 ⁻³ m ³ and sufficiently dissolved. . Next, BaTiO ₃ powder (dielectric material) having an average particle diameter of 1 μm was weighed so that the content in the dielectric material ink was 40% by weight, and then the BaTiO ₃ powder was put into the resin pot, and the rotation speed was 2 Dispersion treatment was performed by rotating at 5 s ^-1 (150 rpm) for 12 hours to produce a dielectric material ink.

  Next, a ceramic sheet was prepared, and the ceramic sheet was subjected to gravure printing using the conductive inks of sample numbers 1 to 10, and then dried, thereby forming a strip-shaped conductor pattern. Thereafter, the dielectric material ink was used, and gravure printing was performed on the portion where the conductor pattern was not formed, followed by drying to form a conductor pattern and a dielectric coating film on the ceramic sheet.

  Next, for sample numbers 1 to 10, the conductor pattern was observed for the presence or absence of structural defects such as breakage or loss, and the smoothness of the conductor pattern was evaluated.

  Here, the structural defect of the conductor pattern is that the conductor pattern is irradiated with transmitted light from the back side of the ceramic sheet, the presence or absence of the transmissive part is observed with an optical microscope, and the structural defect occurs when the transmissive part is generated. It was judged.

  Further, the smoothness of the conductor pattern is measured by using a stylus type surface roughness meter (Surfcom manufactured by Tokyo Seimitsu Co., Ltd.) and measuring the maximum step H of the conductor pattern 16 formed on the ceramic sheet 15 as shown in FIG. Then, the evaluation criteria were set as 0.8 μm.

この表２から明らかなように試料番号１は、インク粘度が０．６Ｐａ・ｓであり、１．０Ｐａ・ｓ以下であるが、数平均分子量が３００〜５０００の低分子量樹脂（第２のバインダ樹脂）が含有されていないため、構造欠陥が生じることが分かった。 Table 2 shows the ink viscosity, the presence / absence of structural defects, the maximum level difference, and the pass / fail judgment of the conductive inks of sample numbers 1 to 10.

As apparent from Table 2, sample No. 1 has an ink viscosity of 0.6 Pa · s and 1.0 Pa · s or less, but a low molecular weight resin (second binder) having a number average molecular weight of 300 to 5,000. Since no resin is contained, it was found that structural defects occur.

  Sample No. 2 has an ethyl cellulose resin (first binder resin) content of 4.0% by weight and a large content of ethyl cellulose resin, so that the ink viscosity is 2.22 Pa · s and 1.0 Pa · s. It was found that the maximum step H exceeded s and became as large as 1.16 μm, and the smoothness of the conductor pattern was inferior.

  Sample No. 10 has a number average molecular weight of the second binder resin as too small as 260, so that the printed coating film cannot be provided with sufficient flexibility, and the conductor pattern becomes a gravure plate when forming the dielectric coating film. As a result, structural defects such as breakage and missing occurred in the conductor pattern.

  In contrast, Sample Nos. 3 to 9 contain an ethylcellulose resin content of 3% by weight and an appropriate amount of 1.0% by weight of various low molecular weight resins having a number average molecular weight of 300 to 5,000. Sufficient flexibility could be given to the printed coating film, thereby avoiding the occurrence of structural defects such as breakage or missing in the conductor pattern. In addition, since the ink viscosity is 0.48 to 0.65 Pa · s and 1.0 Pa · s or less, the maximum step is also 0.55 to 0.66 μm, which can be suppressed to 0.8 μm or less. The smoothness of the pattern was also good.

次いで、実施例１と同様の方法・手順で、試料番号１１〜１６の導電性インクを使用してセラミックシート上に導体パターンを形成し、さらに実施例１の誘電材インクを使用し、導体パターンの形成されていない部位に誘電塗膜を形成した。 The binder resin was blended so that the content of the ethyl cellulose resin was 3% by weight, and the polyisoprene resin (number average molecular weight: 5000) as the low molecular weight resin had a content as shown in Table 3. Conductive inks of Sample Nos. 11 to 16 were produced by the same method and procedure.

Next, a conductive pattern is formed on the ceramic sheet using the conductive inks of Sample Nos. 11 to 16 in the same manner and procedure as in Example 1, and further using the dielectric material ink of Example 1, A dielectric coating film was formed on the portion where no film was formed.

  Next, as in Example 1, the ink viscosity was measured and the presence or absence of structural defects was observed, and the maximum level difference H was measured to evaluate the smoothness of the conductor pattern.

この表４から明らかなように、試料番号１１はポリイソプレン樹脂が含有されていないため、構造欠陥が認められた。 Table 4 shows the results.

As apparent from Table 4, since sample No. 11 did not contain polyisoprene resin, structural defects were observed.

  Sample No. 12 contains a polyisoprene resin, but the content is as low as 0.3% by weight, so that sufficient flexibility cannot be imparted to the printed coating film. occured.

  Sample No. 16 has an excessively high polyisoprene resin content of 11.0% by weight, so that the ink viscosity is 1.20 Pa · s and exceeds 1.0 Pa · s. It was found that the step was 0.98 μm and exceeded 0.8 μm, and the smoothness of the conductor pattern was deteriorated.

  On the other hand, since sample numbers 13 to 15 contain 0.5 to 10% by weight of polyisoprene resin having a number average molecular weight of 5000, the ink viscosity is 0.62 to 0.96 Pa · s. It can be suppressed to 0 Pa · s or less, and it has been found that a conductor pattern excellent in smoothness can be formed without causing structural defects.

次いで、実施例１と同様の方法・手順で、試料番号２１、２２の導電性インクを使用してセラミックシート上に導体パターンを形成し、さらに実施例１の誘電材インクを使用し、導体パターンの形成されていない部位に誘電塗膜を形成した。 The binder resin was blended so that the ethyl cellulose resin and the polyisoprene resin (number average molecular weight: 5000) had the contents as shown in Table 5, and the other methods were the same as in Example 1 except that the sample numbers 21 and 22 were used. A conductive ink was prepared.

Next, in the same manner and procedure as in Example 1, a conductive pattern was formed on the ceramic sheet using the conductive inks of sample numbers 21 and 22, and the dielectric material ink of Example 1 was further used to form the conductive pattern. A dielectric coating film was formed on the portion where no film was formed.

  Then, as in Example 1, the ink viscosity was measured and the presence or absence of structural defects was observed, and the maximum level difference H was measured to evaluate the smoothness of the conductor pattern.

  Next, the ceramic sheets on which the conductor pattern and the dielectric coating film are formed are laminated so that the electrode extraction portions of the conductor pattern are staggered, and are sandwiched between a pair of ceramic sheets on which the conductor pattern and the dielectric coating film are not formed. And pressed to form a laminate. Then, this laminate is fired to produce a ceramic sintered body. Further, a conductive paste mainly composed of Cu is applied to both end faces of the ceramic sintered body, and is baked at a temperature of 800 ° C. Thus, multilayer ceramic capacitors of sample numbers 21 and 22 were produced.

  Next, the capacitance of this multilayer ceramic capacitor was measured. Incidentally, the design value of the capacitance of the sample numbers 21 and 22 is about 100 nF.

この表６から明らかなように試料番号２１は、ポリイソプレン樹脂が含有されていないため、構造欠陥が生じ、静電容量が７６ｎＦとなって構造欠陥に起因した静電容量の低下が認められた。 Table 6 shows the ink viscosity, the presence or absence of structural defects, the maximum level difference, the capacitance, and the pass / fail judgment of sample numbers 21 and 22.

As apparent from Table 6, since sample No. 21 does not contain polyisoprene resin, a structural defect was generated, and the capacitance was 76 nF, and a decrease in the capacitance due to the structural defect was observed. .

  On the other hand, since sample No. 22 contains 3% by weight of polyisoprene resin in the conductive ink, no structural defects occur, and the ink viscosity is 0.68 Pa · s, which is 1.0 Pa · s or less. Therefore, the maximum step is 0.67 μm, which is 0.8 μm or less. Therefore, the smoothness of the conductor pattern is good, and the capacitance of the multilayer ceramic capacitor is 102 nF, so that the decrease in the capacitance can be suppressed. I understood.

It is sectional drawing which shows one Embodiment of the multilayer ceramic capacitor as a multilayer ceramic electronic component manufactured using the conductive ink of this invention. It is a manufacturing process figure which shows the manufacturing method of the said multilayer ceramic capacitor. It is the perspective view which showed the structure of the laminated body typically. It is an enlarged view which shows the conductor pattern formed on the ceramic sheet.

Explanation of symbols

6 Conductive ink preparation process 8 Dielectric material ink preparation process (ceramic raw material ink preparation process)
10 Dielectric coating formation process (ceramic coating formation process)
11 Laminate manufacturing process 12 Firing process

Claims (5)

A gravure printing ink containing at least an inorganic powder, a binder resin, and an organic solvent,
The binder resin was selected from an ethyl cellulose resin, a number average molecular weight of 300 to 5000, and selected from terpene resins, terpene phenol resins, petroleum resins, polybutadiene resins, polyisoprene resins, and polyether resins. And at least one low molecular weight resin,
The gravure printing ink, wherein the content of the low molecular weight resin is 0.5 to 10% by weight.   2. The gravure printing ink according to claim 1, wherein the inorganic powder is a conductive powder, and the ink is a conductive ink.   The gravure printing ink according to claim 2, wherein the conductive powder is nickel powder. A conductive ink production step for producing the gravure printing ink according to claim 2 or 3,
Conductive gravure printing on the ceramic green sheet using the conductive ink, a conductor pattern forming step of forming a conductor pattern,
A ceramic raw material ink preparation process for preparing a ceramic raw material ink mainly composed of a ceramic raw material;
For the ceramic green sheet on which the conductor pattern is formed, the ceramic raw material ink is used to perform gravure printing on the portion where the conductor pattern is not formed, and a ceramic coating film forming step for forming a ceramic coating film,
A laminate forming step of forming a laminate by laminating a plurality of ceramic green sheets on which the conductor pattern and the ceramic coating film are formed,
A method for producing a multilayer ceramic electronic component, comprising: a firing step of subjecting the laminate to a firing treatment.   5. The method of manufacturing a multilayer ceramic electronic component according to claim 4, wherein the ceramic raw material is a dielectric material.

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