TW201207083A - Method of making conductive paste - Google Patents

Abstract

This invention provides a method of making conductive paste. The conductive paste can maintain high dispersion capability and stable adhesiveness when used as a paste for internal electrodes of a laminated ceramic capacitor. The method of making the conductive paste is characterized by containing step 1 to step 3. Step 1: after heating while mixing a conductive paste comprising at least conductive metal powder, dispersion agent, organic bonder and organic solvent, the conductive paste is passed through a nozzle with an orifice to carry out a pre-dispersion step of the dispersion treatment. Step 2: carrying out a dispersion step of a dispersion treatment on a pre-dispersed and heated conductive paste from step 1 by using a high pressure homogenizer. Step 3: filtering the dispersed conductive paste from step 2 by using a filter.

Description

[Technical Field] The present invention relates to a method for producing a conductive paste which maintains high dispersibility and excellent viscosity stability in a paste for internal electrode of a laminated ceramic capacitor. [Prior Art] With the thinness and lightness of electronic devices such as mobile phones and digital devices, the laminated capacitor H (hereinafter referred to as MLCC) as a wafer component is also expected to be miniaturized, homogenized, and high-performance. The most effective way to achieve this is to reduce the thickness of the internal electrode layer and the dielectric f layer to achieve multilayering. MMLCC is generally manufactured as follows. In order to form the dielectric layer, firstly, the titanate and the polyethylene terephthalate containing the barium titanate (BaTl〇3) as the main component will be charged with f A conductive shaft which is a main component and is dispersed in a carrier containing a resin binder and a solvent, and is printed as a conductive electrode in a predetermined pattern, and dried to remove a solvent, thereby forming a dry film. . Money, the dielectric green sheet formed with the dry shaft is heated and crimped into a two-body state in a multi-layer laminated state, and the material is cut off. In an oxidizing environment or an inert environment, the binder is removed under c ,, Thereafter, heating and calcination are performed in a reducing atmosphere in a reducing atmosphere so as not to oxidize the internal electrode. Next, the calcined wafer was coated and fired, and then nickel or the like was applied to the external electrode to produce MLCC. 100113117 3 201207083 However, in the calcination step, the temperature at which the dielectric ceramic powder starts to be sintered is about c, and delamination is liable to occur because the sintering start temperature and the shrinkage start temperature of the nickel metal powder are relatively large. (interlayer peeling) or structural defects such as cracks. In particular, with the small size and high capacity, the layer is significantly more or the thickness of the ceramic layer is thinner, and the occurrence of structural defects becomes, for example, in the usual internal electrode recording paste, at least until the start of sintering. The vicinity of the temperature at which the shrinkage is made is a barium titanate system similar to the composition of the dielectric layer, and the acid = additive is the main component. Its =::: :2, °仃 is, suppressing the sintering shrinkage of the internal electrode layer and the dielectric layer. Further, the addition of the ruthenium can alleviate the trouble of the influence on the electric power characteristics such as the increase in the dielectric loss when the main element of the dielectric layer and the constituent element of the dielectric powder contained in the electrode paste ==. In recent years, with the demand for smaller size and larger capacity of MLCC, the internal electrode layer of powder and the ceramic layer using barium titanate and the like, and the progressive thinning of the '|i layer are progressing rapidly. Therefore, it is used for the conductive paste of conductive paste, such as conductive paste, and (iv) powder atomization and enthalpy dispersion. However, due to the mechanical shear accompanying the micronization of the conductive metal powder and the ceramic powder: Yi 2 = Therefore, only the conductive adhesive of the dispersed state required by the conventional machine is used. Paste, difficult 100113117 201207083 to obtain a smooth dry film or high dry film density. Then, as in Patent Documents 1 and 2, in order to process the fine particle powder until the desired dispersibility is obtained, it is necessary to increase the manufacturing man-hour to manufacture the conductive paste. As a result, the manufacturing time becomes long. Further, in the usual method of producing a conductive paste using a three-roller, the raw material is kneaded and then dispersed, and the viscosity is adjusted as needed. However, in the production method, even if the manufacturing man-hour is considered There is still a limit to dispersing the conductive metal powder or ceramic powder of the fine particles. On the other hand, as a method other than a three-roller for dispersing a conductive metal powder such as a conductive metal powder or a ceramic powder such as a ceramic powder in a carrier or a solvent, Patent Documents 3 and 4 disclose a ball mill or a bead mill. A method of mechanically dispersing and pulverizing. However, in the dispersion method using a bead mill, there is a problem that the conductive metal powder is deformed by the medium, and in the dispersion method using the ball mill, when the conductive metal powder is firmly aggregated, it is sufficiently There is a limit to dispersion. Recently, a method of producing a conductive metal paste using a high-pressure homogenizer and a conductive paste using the same has been proposed as a method of dispersing a three-roller, a bead mill, or a ball mill (for example, refer to Patent Document 5). 6). In Patent Document 5, after the surface of the metal particles and the ceramic particles are wetted, a conductive paste is produced by colliding with nozzle jets ejected from nozzles provided in opposite directions by using a high-pressure homogenizer, but In this method, the jet flow jetted from the nozzle by the south pressure homogenizer is produced by the paste viscosity limit of 100113117 201207083, and the high-pressure homogenizer is used to treat the slurry with the organic carrier at normal temperature. The problem that occurs is that the collision force generated by the high-pressure homogenizer cannot effectively act on the conductive metal powder or the ceramic powder because the impact force imparted to the conductive metal powder or the ceramic powder is hindered by the organic carrier. Disperse. In addition, Patent Document 6 reports that a pre-mixed inorganic powder and an organically-dissolved coarse-packed_Korean homogenizer are subjected to dispersion treatment to produce a second conductive material; and the electrically conductive paste is used to prepare an electric egg. 7 'To make β, but to know the compounding method of the electric rubber compounding method, use a high-speed shearing machine or a planetary mixer such as two or more axes to control the inorganic powder such as metal powder or shout powder. It is mixed with organic matter (organic solvent, y, organic carrier, etc.). However, in these kneading methods, the organic carrier is mixed with a sufficient amount, a conductive metal powder or a pottery, and the surface is in a state of insufficient wetting, etc. The use of the kneading method by the kneading method is performed. In the case of the dispersion processing, the following problems are likely to occur. In the first place, the viscosity of the conductive coarse paste is increased by the addition of the organic vehicle, and the result is insufficient in maneuverability, and it is difficult to carry out the dispersion treatment using the high pressure homogenizer. In the conductive paste, there is an organic carrier which is not completely mixed, and when it is introduced into the still-pressure homogenizer, the solid component containing the organic carrier is attached to it to become difficult to operate normally. 100113117

S 201207083 Secondly, the collision force of conductive metal powder or ceramic powder produced by the organic carrier is obstructed by the _»_丄巧岣化化器. The buffer body 'mechanical shearing force seven coffee 1 _u , , , and the method effectively acts on the conductive metal powder or the ceramic powder, and the medium to the wall i can be set to have sufficient dispersibility). Fourth, since the surface of the conductive metal powder or the π π ^ 4 porcelain powder is not sufficiently wetted, the conductive paste is hardly clean. In addition, since there is a large amount of agglomerate than the nozzle, the nozzle is The frequency of Lu Wang’s congestion is getting higher. Further, although the use of the present invention does not differ from the J' value as a method of improving the monthly nature of the solder paste, Patent Document 7 reports _. + , a method of passing it through the orifice, but in the form of fine particles The conductive metal powder or shouting powder cannot be dispersed. In addition, in the case of the treatment with a 3-roller, since the conductive Meng powder is formed into a flake shape immediately after the start, or because the machine is only weak in mechanical shearing force, the raw material powder == In the case of the dragon's non-filament, the dispersion of the usual "conducting metal powder and ceramics" includes the following processes, agents and dispersions. (1) Conductive gold and botany "wetting", that is, a process in which air in a void on the surface of the secondary particle and the secondary particle is replaced by an organic solvent; (2) a process in which the secondary particle is dispersed and pulverized by a disperser; The process by which the dispersant adsorbs on the surface of the dispersed, pulverized particles to "pre-aggregate". 100113117 201207083 In the dispersion process, the pretreatment step of the kneading and stirring using a stirrer or the like affects the wettability of the conductive metal powder and the ceramic powder or the time of the treatment in the next dispersion step, and uses a disperser such as a 3-pair machine. The dispersing step affects the dispersibility of the conductive metal powder and the shim powder, and in the case where the dispersibility of the particles is poor after the dispersing step, since the dispersing agent is not adsorbed on the surface of the particle, it is difficult to prevent re-aggregation and disperse The stability is degraded. On the other hand, the atomization of the conductive metal powder or the ceramic powder is in the mainstream, but in addition to dispersing the particulate inorganic powder, the conductive paste using the particulate inorganic powder may be caused by the passage of time. Viscosity change problem.疋Because when the viscosity of the paste changes, due to the change in printability, an appropriate film thickness or shape cannot be obtained at the time of printing, and it is impossible to manufacture an electrode or the like having stable quality. On the other hand, Patent Document 8 proposes a conductive paste obtained by using a nickel powder in which Ni/Ni (0H) is stored at a specific composition ratio within a specific composition ratio. However, with the micronization of the recorded powder, in order to control the viscosity change of the conductive paste due to the warp, the selection of the dispersant or the adsorption of the dispersant to the nickel surface is important. In particular, for the conductive paste using the micro-reduced recording powder of 〇2μ, 'there is a limit in the dispersion by mechanical shearing using a conventional 3 辕 machine' due to the dispersion agent to the nickel surface. The adsorption becomes insufficient, and as a result, it is difficult to control the viscosity change due to the warp. [Patent Document 1] Patent Document 1 [Patent Document 1] Japanese Patent Laid-Open Publication No. JP-A-2006-351348 (Patent Document 2) Japanese Patent Laid-Open Publication No. Hei. No. Hei. No. Hei. No. Hei. No. Hei. No. Hei. [Patent Document 7] Japanese Patent Laid-Open Publication No. Hei 2 〇 _ 〇〇丨 〇〇丨 〇〇丨 〇〇丨 专利 专利 专利 专利 专利 专利 专利 专利 专利 专利 专利 专利 专利 专利 专利 专利 日本 专利 日本 日本 日本 日本 日本 日本 日本 日本 日本 日本 日本SUMMARY OF THE INVENTION (Problems to be Solved by the Invention In view of the above problems, the present invention is capable of producing a highly viscous conductive paste which is conventionally difficult to manufacture using a high-pressure homogenizer for a high-viscosity paste containing an organic vehicle. The method, & the paid dispersibility, and the sticky adhesive properties can be obtained. It can be improved by using the high pressure homogenization benefit in the pre-treatment steps of "pse, ^, ~" and viscosity.制造 「 仃 仃 仃 仃 仃 仃 仃 仃 仃 仃 仃 仃 仃 仃 仃 仃 仃 仃 仃 仃Is a powder or shout powder to exist in the presence of organic dragons, conductivity in the presence of organic carriers, 34 (four) wet 'but in the invention ten, even if the sex, in the pass to the heart (four) silk sweater has flow / ±, #泰IL When the nozzle is a silly nozzle, it may not be buffered by the organic carrier, and the surface of the metal powder or the end of the particle may be easily wetted. In the state of the surface of the conductive metal powder or the powder, As long as it is heated and has a fluidity of conductive paste, in addition, the high-pressure homogenization of the conductive (four) 11 organic carrier is not effectively affected by the organic carrier (4), and the dispersion efficiency is improved. Pre-treatment method for improving the knowledge and using the high-pressure homogenizer

If, in the presence of an organic vehicle, a high-pressure homogenizer can be used = conductive paste can be compared with a conductive paste using a 3-roller or a conductive metal (4) conductive paste produced by using Conductive paste with high dispersibility and excellent viscosity. Further, in terms of viscosity stability, the difficulty of "wetting" was improved, and the dispersion was obtained by using a dispersion of the south pressure homogenization. At this time, since the dispersant is adsorbed on the surface of the particles, the "reaggregation" of the particles can be prevented, so that the dispersion stability of the conductive paste can be maintained even after long-term storage. As described above, the object of the present invention is to provide a conductive paste for laminated electronic components having excellent dispersibility and excellent viscosity stability, which is fine for miniaturization and thinning of laminated electronic components. For the conductive metal powder or (4) powder, there is an organic fine high-viscosity conductive paste, which can also be produced by a high-pressure homogenizer. (Means for Solving the Problem) The invention of the present invention is a method for producing a conductive paste, which is characterized in that it has the following first steps to third steps. 100113117 1〇

S 201207083 [First step] The conductive coarse paste containing at least the conductive metal powder, the dispersant, the organic binder, and the organic solvent is mixed and heated while being heated, and then passed through a nozzle having an orifice. The pretreatment dispersion step of the dispersion treatment. [Second Step] A dispersion step of dispersing the heated conductive paste dispersed by the pretreatment in the first step by a high pressure homogenizer. [Third Step] The conductive paste which has been subjected to the dispersion in the second step is subjected to a filtration step of the filter. According to a second aspect of the invention, in the first aspect of the invention, the orifice having the orifice is arranged in series in two or more to disperse the conductive paste. According to a third aspect of the present invention, in the first aspect of the invention, the orifice has an orifice diameter of 0.2 to 0.5 mm. According to a fourth aspect of the invention, the conductive paste of the first aspect of the invention has a viscosity of 10 Pa·s or less. According to a fifth aspect of the invention, the high-pressure homogenizer according to the first aspect of the invention is subjected to a dispersion treatment at a pressure of 50 to 250 MPa. According to a sixth aspect of the present invention, in the high-pressure homogenizer in which the conductive paste flowing in the second step of the first aspect of the invention has an orifice having an orifice diameter of 0.05 to 0.2 mm. According to a seventh aspect of the invention, the high-pressure homogenizer according to the first aspect of the invention includes a cooler at an outlet portion side of the orifice. 100113117 11 201207083 The eighth invention of the present invention is characterized in that the viscosity of the heated conductive paste in the second step in the first invention is 10 Pa·s or less. According to a ninth aspect of the invention, the conductive paste formed by the first aspect of the invention is characterized in that the content of the conductive metal powder is from 30 to 70% by weight based on the total amount of the conductive paste. According to a tenth aspect of the present invention, in the conductive paste of the ninth aspect of the invention, the conductive paste contains ceramic powder as a sintering inhibitor. (Effect of the Invention) According to the present invention, in the method for producing a conductive paste in a laminated ceramic electronic component, the conductive paste is imparted with high dispersibility by mechanical shearing to realize excellent adhesive properties. The formation of the conductive paste is further used as a paste for the internal electrode of the multilayer ceramic capacitor, and a conductive paste having excellent dispersibility and excellent viscosity stability is realized. [Embodiment] The conductive paste for forming an internal electrode of the multilayer ceramic capacitor of the present invention is obtained by dispersing a conductive metal powder and a ceramic powder in an organic vehicle obtained by dissolving a binder in an organic solvent. Glue. Such a conductive paste is formed by the following three steps. 1. The first step [pre-treatment dispersion step] The conductive coarse paste containing at least the conductive metal powder, the dispersant, the organic binder, and the organic solvent is mixed and heated while being heated, and then passed through a nozzle having an orifice. To carry out the dispersion process. 100113117 12 201207083 2. The second step [dispersion step] (4) The pre-treatment of the disperse material is carried out, and the dispersing treatment is carried out by using a high-intensity sentence to further disperse it. 3. Third step The conductive paste which was subjected to the dispersion treatment in the second step was filtered using a filter. These steps are explained in detail below. [First Step] In the first step, the conductive coarse metal containing at least the conductive metal powder, the dispersant, the binder, and the organic solvent is heated and mixed, and then passed through a section mounted on the drive pump. The nozzle of the orifice, thereby imparting mechanical shear to perform the process of secret dispersion. Further, the reason for the disturbance while heating is to impart fluidity by reducing the viscosity of the conductive paste at the time of pretreatment dispersion. As the kneading system to be carried out in this step, a usual mixing and agitating device such as a propeller type agitation device can be used. In particular, a high-speed stirring and mixing device such as a dispersing machine is preferred. In the pre-treatment dispersion process of the first step ♦, the conductive coarse paste is fed into a nozzle having a boring hole having a predetermined diameter, and when the orifice is passed, the conductive coarse paste is given a shearing force' Disperse processing. As a conveying method for feeding the conductive coarse paste into the nozzle and passing it through the orifice, it is possible to appropriately select and use each of the pumps 100113117 13 201207083, such as a feed pump, a single screw pump, a diaphragm pump, and a gear pump. The pressure applied to the conductive paste by the pump is not particularly limited, but it is preferably used in a range that does not affect productivity or the like, and is preferably 5 kg/cm2 or more. Fig. 2 shows an example of the nozzle 5 and the orifice 6 for pretreatment dispersion. For the inner diameter of the orifice for shearing the conductive coarse paste (hereinafter referred to as the orifice diameter, indicated by the symbol "d" in Fig. 2), it is preferable to use 0.2 to 〇.5 mm. Nozzle for throttling aperture. In the case where the orifice diameter is less than 0.2 mm, it is possible that nozzle clogging occurs in the pretreatment dispersion step, and the surface of the conductive metal powder or ceramic powder is wet in the presence of an organic carrier in the case of more than 〇5 mm. The wetness is not enough. Further, as long as the orifice diameter is a nozzle having an inner diameter of 0.2 to 0.5 mm, it can be combined. The nozzle having the orifice may be either a nozzle having one orifice in one nozzle or a nozzle having a plurality of orifices in one nozzle as shown in Fig. 2. The number of orifices is preferably two or more in series. When so set, only the number of orifices can impart mechanical shear to the conductive paste. Further, the number of orifices is not particularly specified, but the number of nozzles having the number of orifices given the mechanical shear necessary for the pretreatment dispersion step is selected. Further, the distance L between the orifices can be appropriately set in consideration of the adhesive properties such as the viscosity of the conductive paste. As shown in Fig. 2, by connecting a plurality of orifices having narrow gaps in series, the conductive coarse paste is passed, and the inner wall of the flow path of the conductive coarse paste and the orifice is produced.

100113117 S 201207083 The mechanical shearing force of the surface makes the surface of the conductive metal powder or ceramic powder easy to wet. Further, in the present embodiment, the size of the nozzle having the orifice used in the pre-treatment dispersion step is 4.7 coffee in diameter (outer diameter, shown in the circle 2, and the degree is 10 mm (shown in L of Fig. 2). The shape of the nozzle is preferably a cylindrical shape, a straight line having no bending portion or a bent portion, and a material which is not easy to wear, and further, as a material for forming the orifice, for example, diamonds such as sintered diamond and single crystal diamond; Ceramic materials such as oxidation, carbonization, etc.; metals such as stainless steel, iron, titanium, etc. For the pretreatment dispersion of the first step, as a conventional pretreatment method, when only a high, shear mixer or a planet of 2 or more axes is used Stirring device such as mixer: When mixing in the Linlin, the organic carrier, the conductive metal and the ceramics are incompletely mixed due to the wetness of the organic-loaded conductive metal powder or ceramic powder. The large agglomerate of the powder is therefore reduced in the reading efficiency by the high-pressure homogenizer in the second step. Moreover, the conductive gelatin residue is not combined with the body, and the gloss of the dried film is lowered. The front of the conductive paste in the present invention The dispersion step is exemplified in Fig. 3, as shown in Fig. 3, while the heater 2 is heated, and the conductive coarseness in the tank 1 which is given by the mixing purple leaf 3 is passed through the chestnut* through the series connection. Nozzle 5 with a narrow orifice orifice. 第 [Step 2] In the 2nd step of 5H, the pilot batch paste obtained by dispersing the pretreatment in the first step is advanced by a high-chemicalizer. Dispersion. (100113117 201207083 The pressure of the dough homogenizer of the present invention is preferably 50 to 250 MPa, more preferably 100 to 200 MPa. When the pressure is not full, the jet is ejected from the orifice of the thorium IL. Therefore, the speed of the treatment is weak, so that the dispersion is poor. Therefore, the reason why the pressure is 25 GMPa or less is considered to prevent the wear of the components of the disperser and to withstand long-term use. The high-pressure homogenizer that is subjected to the dispersion treatment in the second step is a device that relies on the fine orifice for generating the high-speed jet flow, and the throttling is considered from the viewpoint of productivity or efficiency of the device. It is about 05·05~G.2mm, and, The shape is preferably a straight line which is not easy to wear without the 'f curved portion or the bent portion. Further, the material for forming the orifice may be a diamond such as sintered diamond or single crystal diamond; a material such as oxidation, oxidation, carbon cutting or the like Metals such as steel, iron, and chin are not recorded, and materials of high hardness which are not easy to wear are preferred. Generally, the faster the passage speed of the glue in the orifice, the larger the shear force becomes. The particle size is finer. However, when the particle size of the particles becomes too small 'Because it becomes easy to cause aggregation, in order to maintain the particles in a proper particle size, it is necessary to adjust the orifice passage speed to make the knot The stress acting on the paste after passing through the orifice and the orifice is optimal. The adjustment of the passage speed is performed according to conditions such as the orifice diameter and the treatment pressure, and the orifice is adjusted in speed by the speed of the orifice. The range of ~ 丨〇〇〇m/sec can keep the particles in an appropriate fine particle size state and prevent aggregation. Further, in order to prevent the collision of the adhesive paste against the inner wall of the space portion after passing through the orifice 100113117 16 201207083, the unevenness of the shear force may cause bubbles, and the adhesive may be applied while applying a back pressure. Further, since the stability of the particles is lowered when the temperature of the paste becomes high, and problems such as re-aggregation occur, it is not preferable. Therefore, in order to prevent the temperature of the paste from rising, it is preferable to provide a cooling skirt. The number of dispersion passes in the homogenizer can be appropriately selected according to the required particle size, grain size, and the like. Further, the number of dispersion passages is preferably carried out in accordance with the configuration of the apparatus for circulating the paste. The conductivity of the conductive paste which is subjected to the dispersion treatment in the high-pressure homogenizer in the second step is desirably uniform and low in viscosity, but the viscosity of the conductive paste when the high-pressure homogenizer is applied is preferably 10 Pa. 8 or less. It is better to still be below s. For example, as shown in the relationship between the temperature and the viscosity of the conductive paste as shown in Fig. 4, the adhesive/dishness of the conductive paste at a viscosity of 25 C is 3 GPa · s when heated, at the temperature of the conductive paste. As the rise, the viscosity decreases. In the case where the viscosity is higher than 10 Pa.s, the conductive paste has no fluidity. Therefore, when it is put into the high-pressure homogenizer, the treatment pressure is not improved, and the dispersion treatment cannot be performed. In addition, when the temperature of the conductive paste is higher than 7 〇〇c, the viscosity of the conductive paste is not more than 10 Pa·s, but the safety and flammability of the organic solvent used are safe and conductive. The compositional balance of the adhesive paste is easy to change and is therefore not good. The local pressure homogenizer used is a MiCr〇fluidizer (manufactured by miCr〇fhiidiCS), a nan〇mizer (manufactured by Yoshida Masaki Co., Ltd.), and a Nan〇3000 (manufactured by the US) ), the job light (10) is fine. (shares) 100113117 17 201207083 system) and so on. [Third Step] The third step is a step of transitioning the conductive paste subjected to the dispersion treatment by the high-pressure homogenizer of the second step with a filter of a predetermined specification. As a filter, the filtration precision was filtered out at 99%, and the filter was filtered using a mesh of 5 μm. In the case of using a filter having a mesh opening of more than 5 from 111, "undispersed matter, coarse particles, and the like which cannot be removed from the inorganic material" when a substance larger than the thickness of the dielectric layer is mixed, the flatness is lowered due to the occurrence of protrusions on the surface of the adhesive coating film. Therefore, a conductive paste excellent in smoothness cannot be obtained. In addition, filtration by a filter having a meshing degree of 99% and a precision of 5 μm or less in the mesh means that 99% or more of the particles are added in excess of 5 μm by 99% filtration accuracy. For example, a one-way test based on seven kinds of JIS ζ 8901 test powder (5 mg/L dispersion, i〇L/min) can be cited. Further, the material for filtration 'is metal, PTFE (polytetrafluoroethylene), polypropylene, etc., but is not limited to these materials. Further, the structure of the filter used herein may be, for example, a film type, a pleat-type, a dep-type, or the like, but is not limited thereto. [Conductive Paste Structure] In order to obtain a conductive paste which can improve the smoothness of the dried coating film and the density of the dried film, the nickel powder is preferably a fine powder having a particle diameter of 0.03 to 5.5/>1111. When the nickel powder is aggregated to produce coarse particles, when the particle size of the nickel powder exceeds 0.5 μm, the film formation property when the coating film of the paste is thinned is deteriorated, and not only 100113117 201207083 can be obtained. Capacity, and ^ and the probability of mixing coarse particles increases, and it is prone to the undesirable phenomenon that the breakdown voltage (BDV) decreases. Further, when such an electrode _ which is required to be thinned is formed, the dryness of the dryness is sufficiently sufficient, and the filling of the nickel powder particles becomes insufficient, and the desired dry film density cannot be ensured. On the other hand, the reason why the particle diameter of the nickel powder is set to 0.5/mi or less is that the electrode film is formed to have an excellent continuity in the thinning of the multilayer capacitor. Further, when the particle size is low and the purity is called m, the specific surface area of the particles becomes too large, and the surface activity of the metal particles becomes too high, which not only adversely affects the dry dance and the debonding agent. And it is possible that the viscosity characteristics of the field may not be obtained or deteriorated during the long-term storage of the conductive__. In the present invention, the particle diameter of the nickel powder is a particle diameter calculated based on the comparative surface area unless otherwise specified. Its calculation formula is shown in Mathematical Formula 1. [Math 1] Particle size of nickel powder == SA, Ρι=8·9 (true density of nickel) SAl · Specific surface area of nickel powder (BET method) Conductive metal particles in conductive paste of the present invention The ratio is preferably 30 to 70. When the amount of the conductive metal particles is less than 30% by weight, after the calcination, the thickness of the electrode is remarkably thin, the electric resistance value is increased, or the formation of the electrode film is insufficient to lose the conductivity. The electrostatic capacitance may not be obtained. When it exceeds 100113117 19 201207083 by 70% by weight, the electrode film becomes difficult to be thinned. The conductive metal powder is more preferably set to 4 to 60% by weight based on the entire adhesive. In the case where ceramic powder is added as a sintering inhibitor to the conductive paste, it can be selected from BaTi〇3 or the like which is usually a perovskite-type oxide or a variety of additives. Further, it is preferably the same composition or a similar composition as the ceramic powder used as the main component of the electric layer of the MLCC. The ceramic powder can be used by a solid phase method, a hydrothermal synthesis method, or an alkoxide method. A ceramic powder produced by various methods such as a sol-gel method, and a ceramic powder which is dispersed and pulverized by a device such as a bead mill or a high-pressure homogenizer, may be added to the ceramic powder as needed. The particle size of the ceramic powder is preferably in the range of 仏(1) to 仏. When the particle size of the ceramic powder exceeds 〇.2μηη, the density of the dried film decreases. In the dried film, The gap formed by the accumulation of the nearly spherical nickel powder particles is filled with the ceramic powder. When the particle diameter of the ceramic powder exceeds 〇.2/1111, it becomes difficult to enter between the contact points of the nearly spherical nickel powder particles, and therefore, it is difficult The desired dry film density is obtained, and the effect of delaying the sintering start temperature of the conductive paste to the sintering start temperature of the ceramic layer is weakened. On the other hand, when the particle diameter of the ceramic powder is lower than ο. When οίμιη, the sintering retardation effect of the conductive paste is hard to be manifested, and structural defects such as delamination or cracking occur. Further, the above-mentioned dry film density is lowered or the agglomerated powder of the ceramic powder is 100113117.

20 S 201207083 The problem of deterioration in reliability (lower insulation resistance, increase in short-circuit rate, etc.) of the capacitor due to thinning of the dielectric layer is difficult. In the present invention, the particle diameter of the ceramic powder is a particle diameter calculated based on the comparative surface area of the BET method unless otherwise specified. The calculation formula using barium titanate as an example is as follows. [Math 2] Particle size of barium titanate powder = — SA2 X p2 /02=6.1 (true density of barium titanate) SA2: specific surface area of barium titanate powder (BET method) In addition, the content of ceramic powder It is preferably 3 to 25 parts by weight based on 100 parts by weight of the conductive metal powder. More preferably, it is 5 to 15 parts by weight based on 1 part by weight of the conductive metal powder. In the case where the content of the ceramic powder is less than 3 parts by weight, for example, the sintering of the nickel powder cannot be controlled, and the sintering shrinkage behavior of the internal electrode layer and the dielectric layer becomes remarkable. On the other hand, when Tao: is the powder of more than 25 parts by weight, for example, because of the Taoman particles of the dielectric layer: ^, ·. t " The thickness of the layer is swollen from the internal electrode layer, and the composition is shifted, which adversely affects the electrical properties of the permittivity. Further, when the pottery: is 3 liters/3 parts by weight of the private end, since the sintering of the internal electrode starts from a low temperature, the difference in the sintering temperature between the internal electrode layer and the dielectric layer becomes large, so that a calcination crack is generated. In the conductive paste of the present month, the dot resin is used in the form of an organic vehicle which is combined with an organic solvent in advance 100113117 201207083. Adhesive_filament uses a substance that dissolves; the granules, but because A organically dissolves it uniformly, it needs to be sufficient _ The result is that the mixing process of the first step takes too much time, from the decrease in productivity or the mixing of the foot In view of financial considerations, there is (4) quality insurance, and in the sense of excluding it, it is better to use organic carriers. Poor wind The binder resin may, for example, be mercapto cellulose, ethyl cellulose, ethylene cellulose, fluorene fiber, propylene ray, polyethyl cycline = wax, and one or more of them may be selected. For its molecular weight, it is a solvent: fat. Further, the tree of the molecular weight of the conductive (10)tr~2嶋 is 2.0 to gamma t%. In the case where the resin is not read in the U to 5 domain, and the viscosity of the printing is particularly good, (4), it is difficult to obtain a suitable force for the screen. Called the paste carbon amount of acetic acid iso-propionic acid di- or di-propionic acid, di-alcohol, dihydroacetic acid (four), Bo S day, butyric acid iso-fusic acid, isobutyl butyl glycol monobutyl ether acetate, a 兵 soldier Anthracene oxime ester, ethyl propylene glycol decyl ether acetate, and the like. θ is not particularly limited as the dispersing agent contained in the conductive paste, and the cation-based dispersing agent, the anionic dispersing agent, the non-separating agent, and the dispersion are sufficient to disperse the dispersing agent in the conductive gold two. A known dispersant is used for the binder and the organic solvent 100113117 M. In particular, the anionic dispersing agent is preferably used in the case of the above-mentioned sub-group 22 201207083, and examples thereof include a slow acid dispersing agent, a sizing agent, and a phosphate dispersing agent. These dispersing agents may be used alone or in combination of two or more. The anionic dispersant has a large adsorption power to the inorganic surface, and contributes to the improvement of the dispersibility of the inorganic component by the surface reforming effect. This improves the smoothness and the dry (four) density of (4). The average molecular weight of the "Haidaozheng agent is preferably 2 (8) ~ 2 〇〇. More preferably 300 10 baht. When the average molecular weight is less than 2 Å, the particles do not obtain sufficient electrostatic repulsion, and sometimes the dispersibility or storage stability of the particles is lowered. Usually, the agent is adsorbed on the surface of the particles to form an adsorption layer of the dispersant, and the paste is given an electrostatic repulsion or a three-dimensional repulsive force to obtain a paste having excellent dispersibility. However, '', for the passage of time, due to the collision between the particles, the particles will agglomerate beyond the repulsive force of the adsorption layer, so the average molecular weight is above 200. In addition, when the molecular weight is greater than 2GGGG, there is When the compatibility with the organic vehicle and the organic/troreal agent is lowered, or aggregation between the particles is caused, and the dispersibility and the storage stability are lowered, the viscosity of the paste is also increased. The amount of the added stem with respect to the conductive metal powder is preferably 〇1〇 to 2.00% by mass, more preferably 〇2〇 to 10〇 by mass, based on 1 part by mass of the inorganic substance. When the dispersing agent is less than 1 part by mass, it is difficult to obtain sufficient dispersibility. On the other hand, when it exceeds 2. 〇〇 mass damage, there is a problem that drying property is deteriorated or the dry film density is lowered. In order to impart viscosity adjustment or moderate viscosity characteristics of the conductive paste, the conductive paste in the present invention may be added with an organic solvent according to the purpose or may have a binder of 100113117 23 201207083. The agent is basically preferably a material constituting the conductive paste. Further, a known additive such as an antifoaming agent, a plasticizer or a tackifier may be added as needed. [Examples] The present invention will be described in detail based on more specific examples. Further, the scope of the present invention is not limited to the examples. [Characteristics of Conductive Paste] (1) Viscosity of Conductive Paste The conductive adhesive of the present invention The viscosity of the paste was measured using a Brookfield B-type viscometer at i rpm (sliding speed = 4se (rl), and the viscosity shown in the example indicates that 8 hours after the adhesive was produced. (2) The change rate of the time-dependent viscosity of the conductive paste to the conductive material (4) The viscosity change over time, the viscosity after the 8 hours after the manufacture of the conductive adhesive is the initial viscosity, at room temperature ( 25. After 30 days of standing under the armpit, 'the initial viscosity and the viscosity of the re-measured viscosity are divided by the initial viscosity, expressed as a percentage (〇/〇). In addition, the change rate of the time-dependent viscosity of the conductive paste is better. The smaller the better. (3) Surface roughness (Ra) The cloth (gap thickness: 5 Mm) was coated on the glass substrate, and then dried in air at 12 ° C for 5 minutes to prepare a dried film having a thickness of about 100 Å. The optical method of the offset interference method measures the protrusion of the surface of 100113117 24 201207083. Specifically, the light source limited to a specific wavelength region irradiates light onto the sample and the reference mirror, and uses light irradiated on the sample and the reference mirror. The interference fringe observes the surface state. Further, the sample is observed from the interference fringe of the light in the direction in which the light is irradiated every 1/4 wavelength. The surface roughness of the dried film uses the optical interference surface shape. The measurement was performed by measuring the penetration (manufactured by WYCO NT-1100). (4) Glossiness and Dry Film Density (DFD) The method for measuring the density of the dried film was measured by the following method. The conductive paste was printed on pET祺 in an area of 5×10 〇cm, and then it was made into a film thickness of 3 〇, and then dried in the air at 12 (TC), and a gloss meter (manufactured by Horiba, Ltd.) was used. (4) Coffee: IG, measure the gloss of the dried film of the laminating paste (6〇t> Further, ', cut to ixlcm, measure the thickness / _ film cut and dry out the density of dry 。. The determination of the density of dry 貘 is Conductive line -, paste m paste printing on the pe τ film, the wheel division with the dielectric layer green sheet 2: the dry film density is the density of the conductive enamel after drying. Fiber used organic, she _ quality ~ fiber The alizarin is used as a binder resin to form a solvent, and is heated to 60t. 087 centroid "Alcohol as organic, the same as the organic carrier __., with 18% by mass of ethyl hydroxyethyl 25 201207083 Cellulose is used as a binder resin component, and is prepared by mixing 82% by mass of propionate as an organic solvent and heating to 60 ° C. [Example 1 j 47 mass % of particle diameter 0.4 μηι in a conductive metal powder Nickel powder (Nl) '21.69 mass% organic carrier A, and further 0.2% by mass of a dispersant, 31.11 mass: g:% terpineol, and mixed with the mixture after heating, and then throttled at the outlet portion of the drive pump so that the six orifice diameters are 〇.5 mm In the nozzles in which the holes were connected in series, 6 〇t of the conductive coarse paste was passed to impart mechanical shear, and a conductive paste which was subjected to pretreatment dispersion was prepared, and the gloss of the dried film of the paste was measured. Table 丨 to Table 3. [Example 2] 47% by mass of 〇4/xm& nickel powder (Ni) was blended in the conductive metal powder, and 1175 mass% of particle diameter 〇1^^ was blended in the ceramic powder. Barium titanate (BT), 19.88% by mass of organic carrier A, and further blended with 〇3 mass% of 诏21.诏7 mass% of box alcohol, mixed and heated while being heated, and then attached to the drive record outlet In the nozzles in which the six orifice orifices are connected in series with the orifices of the 〇5 position, '6 〇t of conductive coarse paste is passed to impart mechanical shear, and pre-treatment dispersion is performed. Pre-treated and dispersed conductive paste is used according to the throttle aperture Bmm, and the treatment of Lili (10) is slightly Over the number of times ^: the set member of dust and dispersion treatment is homogenized to prepare a conductive adhesive transfer 'to filter out filtration accuracy of 99%, using a fine mesh or less suddenly through the carry 100,113,117

S 26 201207083 Line filtration treatment, making the required conductive paste of the road, measuring the adhesive properties (viscosity, surface roughness, DFD) and the rate of change of the point sore. The results are shown in Tables 1 to 3. [Example 3] A desired conductivity impurity was produced under the same conditions as in "Bei Shi Example 2" except that the number of dispersion passes by high pressure homogenization crying was set to three times, and the adhesive property and viscosity change rate were measured. The results are shown in Table 丨 to Table 3. [Example 4] The desired conductive paste was produced under the same conditions as in the case of Example 2, except that the number of dispersion passes by the high-pressure homogenization dehumidification γ was set to 5 times. The paste was measured for the adhesive properties and the viscosity change rate. The results are shown in Tables to Table 3. [Example 5] The conductive metal powder was mixed with a powder (10) of 48·丨2 f% by particle diameter g 2 (four), In the ceramic powder, 4 81% by mass of 〇. 爪 的 钛 ' ' ' 16 16 16 16 16 16 16 16 ' ' ' 16 21. 21. 21. 21. 21. 21. 21. 21. 21. 21. 21. 21. 21. 21. 21. 21. 21. 21. 21. 21. 21. 21. 21. 21. 21. 21. 21. Acidic difference, 8 65f4% ethylene glycol monotoplyacetate is designed to be combined with '-edge heating-side mixing, and then installed in the outlet of the drive to make u throttle orifices 2mm orifices in series , pre-treatment dispersion. In the nozzle, make the conductivity of 6G °C coarse _ through the incoming machinery ~, '& one, ._· square package then, 6 (TC before the TC The conductive paste of the dispersion is made of a high-pressure homogenizer (4) which is set by a machine having a pore diameter of 13.13 mm, a treatment pressure of 2 〇〇 MPa, and a number of times of passage of 5, that is, a machine member, and a dispersion treatment to produce a conductive _ paste ^ 100113117 27 201207083 The filtration precision of 99% filtration was used, and the filter of the filter of 1 μm or less was used, and the required conductive paste was prepared, and the adhesive property and viscosity change rate were measured. The result is shown in Table 1 - Table. 3. [Example 6] In the conductive metal powder, 4 8.12% by mass of 〇. 〇 8 μm of nickel powder (Ni) 'mixed with 4.81% by mass of the particle size 0 03 barium titanate (BT), 16.06% by mass of the organic carrier B, further blending 43% by mass of a dispersant, 21.93% by mass of isopropionate propionate, and 8.65 mass% of ethylene glycol monobutyl ether acetate, and mixing while heating Then, in a nozzle which is connected in series at an outlet portion of the drive pump and has 11 orifices having a diameter of 〇2 mm, a conductive coarse paste of 60° C. is passed to impart mechanical shearing. Pre-treatment dispersion. Then 'will be 60. The conductive paste is prepared by dispersing a high-pressure vaporizer set at a throttle aperture of 0.09 mm, a treatment pressure of 250 MPa, and a number of times of dispersion, to prepare a conductive paste, and then filtering the filter with 99% filtration. The mesh of the following filters was used to prepare the desired conductive axis, and the adhesive properties and viscosity change rate were obtained. The results are shown in Tables 1 to 3. [Comparative Example 1] In the conductive metal powder, 47f% by volume of powder (Ni), 21.69f% of organic carrier A', and further, G.2% by mass of dispersant, and 31.11 mass%/〇 of β-alcohol'- - After mixing the impurities, after installation at 100113117

S 28 201207083 Drive the system's σ to make the throttle aperture! (10) m orifices in each of the six connected spray backs 'make 6Gc of conductive coarse paste through the job to mechanical shearing' to produce a pre-processed dispersion of conductive paste, the gloss of the dry film degree. The results are shown in Tables 1 to 3. [Comparative Example 2] 47% by mass of a recording powder (Nl), 21.69% by mass of the organic carrier A, and 0.2% by mass of a dispersant, and 3 L of a 11% by weight of terpineol were added to the conductive metal powder. The conductive paste was prepared by mixing and stirring using a planetary mixer (manufactured by PRIMIX Co., Ltd.) to measure the gloss of the paste. The results are shown in Tables 1 to 3. In addition, the stirring time of the planetary mixer was set to 30 minutes. [Comparative Example 3] The conductive metal powder was mixed with 47% by mass of 〇·4μηι recorded powder (1^), 21.69% by mass of organic carrier Α', and further mixed with 0.2% by mass of a dispersant and 31.11% by mass of a product. The alcohol was mixed and stirred using a planetary mixer (manufactured by PRIMIX Co., Ltd.) to prepare a conductive paste, and the gloss of the dried film of the paste was measured. The results are shown in Tables 1 to 3. In addition, the stirring time of the planetary mixer was set to 120 minutes. [Comparative Example 4] A nickel powder (Ni) having a mass ratio of 47 mass% to 0.4 0.4 μm was blended in the conductive metal powder, and 11.75 mass% of a particle diameter of 0.1 from 111 barium strontium titanate (BT), 19.88 was blended in the ceramic powder. % by mass of organic body A, and further blended with 0.3% by mass of 100113117 29 201207083 and 21.07% by mass of terpineol, using a planetary mixer (?111)^1乂, manufactured by TKhivis-disper-mix 3D-125) After the scramble, the conductive paste was prepared by a dispersion treatment using a 3 轺i machine, and the adhesive properties (viscosity, surface roughness, DFD) and viscosity change rate were measured. The results are shown in Tables 1 to 3. [Comparative Example 5] A conductive powder of 47% by mass of 〇.4μηη was mixed with (Ni), and 11.75% by mass of yttrium titanate (BT), 19.88 was added to the ceramic powder. 5% by mass of organic carrier A, further blended with 3% by mass of dispersant and 21.07% by mass of terpineol, and mixed with scramble after heating, and six orifices are attached to the outlet of the drive pump. 〇. 5mm orifices are connected in series with nozzles, making 60. (The conductive coarse paste was mechanically sheared and subjected to pre-treatment dispersion. Then, a conductive paste was prepared by performing a dispersion treatment using a 3-roller, and the adhesive properties (viscosity, surface roughness, DFD) and the adhesive properties were measured. The change rate of viscosity was shown in Table 丨 to Table 3. [Comparative Example 6] A nickel powder (Νι) of 48.12 mass% of 〇.2μηη was blended in the conductive metal powder, and 4.81 mass was blended in the ceramic powder. Barium titanate (BT) having a particle diameter of 〇〇4/^111, 16.06% by mass of an organic carrier b, further blending 43% by mass of a dispersant, 21.93% of a propionic acid, and 8.65 mass% Ethylene glycol monobutyl ether acetate vinegar was mixed and stirred using a planetary mixer (TKhiVis-diSper-mix 3D-125 type manufactured by PRIMIX Co., Ltd.), and then a conductive paste was prepared by a 3-roller to measure the adhesive properties. The viscosity was changed to 100113117 201207083. The results are shown in Tables 1 to 3. [Comparative Example 7] 48.12% by mass of nickel powder (Ni) having a particle diameter of 0.08/^111 was blended in the conductive metal powder to be blended in the ceramic powder. 4.81% by mass of barium titanate (BT) having a particle size of 0.03/mi 16.00% by mass of the organic vehicle B, further blended with 0.43 mass% of a dispersant, 21.93 mass% of propionate propionate, and 8.65 mass% of ethylene glycol monobutyl ether acetate, using a planetary mixer (TKhivis-made by PRIMIX) Disper-mix 3D-125 type) After mixing and mixing, the heated conductive paste is dispersed by a high-pressure homogenizer set according to a treatment condition of a orifice diameter of 0.09 mm, a treatment pressure of 250 MPa, and a number of dispersion passages of 10 times. The conductive paste was prepared to measure the adhesive properties and the viscosity change rate. The results are shown in Tables 1 to 3. 100113117 31 201207083 [Table i] Conductive Paste Conductive Metal Powder Ceramic Powder Organic Carrier Dispersant Organic solvent type particle size M content [% by mass] Species particle size content [% by mass] Species content [% by mass] Content [% by mass] Species content [% by mass] Example 1 Ni 0.4 47 - - - A 21.69 0.2 Alcohol 31.11 Example 2 Ni 0.4 47 BT 0.1 11.75 A 19.88 0.3 Terpineol 21.07 Example 3 Ni 0.4 47 BT 0.1 11.75 A 19.88 0.3 Terpineol 21.07 Example 4 Ni 0.4 47 BT 0.1 11.75 A 19.88 0.3 Terpineol 21.07 Example 5 Ni 0.2 48.12 BT 0.04 4.81 B 16.06 0.43 Isoamyl propionate, ethylene glycol monobutyl ether acetate 21.93 > 8.65 Example 6 Ni 0.08 48.12 BT 0.03 4.81 B 16.06 0.43 Propionic acid Isoform S, ethylene glycol monobutyl ether acetate 21.93 > 8.65 Comparative Example 1 Ni 0.4 47 - - - A 21.69 0.2 'terpineol 31.11 Comparative Example 2 Ni 0.4 47 - - - A 21.69 0.2 Terpineol 31.11 Comparative Example 3 Ni 0.4 47 - - - A 21.69 0.2 Terpineol 31.11 Comparative Example 4 Ni 0.4 47 BT 0.1 11.75 A 19.88 0.3 Terpineol 21.07 Comparative Example 5 Ni 0.4 47 BT 0.1 11.75 A 19.88 0.3 Terpineol 21.07 Compare Example 6 Ni 0.2 48.12 BT 0.04 4.81 B 16.06 0.43 Propionic acid iso- vinegar, ethylene glycol monobutyl ether acetate 21.93, 8.65 Comparative Example 7 Ni 0.08 48.12 BT 0.03 4.81 B 16.06 0.43 Propionic acid vinegar, ethylene glycol Monobutyl ether acetate 21.93 > 8.65 100113117 32

201207083 [Table 2] Step 1 · Pre-Processing Dispersion Step 2: Dispersing Process Step 3: Transitioner Transition Method Throttle Conductive Coarse Paste Temperature [°C] Method Throttle Aperture [mm] Processing Pressure [ MPa] Pass times [times] Conductive paste temperature [°C] Filter condition diameter [mm] number [number] Overpass ' Precision transition device Example 1 Throttle cut 0.5 6 60 Example 2 Throttling Hole shearing 0.5 6 60 High pressure homogenizer 0.19 100 1 60 99% filtered mesh L3/xm Example 3 below orifice cutting 0.5 6 60 High pressure homogenizer 0.19 100 3 60 99% filter mesh 3μιη The following example 4 orifice cutting 0.5 6 60 high pressure homogenizer 0.19 100 5 60 99% filtration mesh 3 / xm The following example 5 orifice cutting 0.2 11 60 high pressure homogenizer 0.13 200 5 60 99 %Filtering mesh ljum The following example 6 orifice cutting 0.2 11 60 high pressure homogenizer 0.09 250 10 60 99% filtering mesh below comparison example 1 orifice cutting 1.0 6 60 - - ink - - - - Comparative Example 2 Planetary Mixer for 30 minutes - - 25 - - - - - - - Comparative Example 3 Planetary Mixer for 120 minutes - - 25 比幸交例4 Planetary agitator - - - 3 machine - - - - - - Comparative example 5 orifice cutting 0.5 6 60 3 rhyme - - - - - Comparative example 6 Planetary mixer - - - 3_ - - - - - - Comparative Example 7 Planetary Stirrer - - - High Pressure Homogenizer 0.09 250 10 60 - - 33 100113117 201207083 [Table 3] Dry Coating Gloss Glue Characteristic Viscosity Change Rate [%] Viscosity [Pa · s] Surface roughness R a [/mi] DFD [g/cm3] Initial 1 day 10 days 30 days Example 1 34 - - - - - - - Example 2 - 27 0.26 5.8 0 5 7 9 Example 3 - 24 0.24 6.0 0 3 6 7 Example 4 - 24 0.24 6.0 0 3 6 6 Example 5 - 20 0.18 5.8 0 5 7 7 Example 6 - 25 0.12 5.7 0 4 7 8 Comparative Example 1 3 - - - - - - - Comparative Example 2 4 ** - - - - - - Comparative Example 3 5 - - - - - - - Comparative Example 4 - 32 0.28 5.6 0 13 27 30 Comparative Example 5 - 30 0.27 5.6 0 11 23 25 Comparative Example 6 - 28 0.22 5.5 0 15 26 35 Comparative Example 7 - 28 0.14 5.6 0 12 19 24 [Effect of pre-treatment dispersion step of the first step] The effects of the pre-treatment dispersion step were as shown in Table 1 and Comparative Example shown in Table 4. 1 to 3 before the first step The gloss of the dried coating film of the conductive paste in the dispersed state will be described. [Table 4] Step 1: Pre-treatment Dispersion step Dry coating film gloss method Throttling hole constant Μ phase diameter [mm] number [one] Shou electric 1 king bud and ambiguous temperature [°c] Example 1 Throttle shear 0.5 6 60 34 Comparative Example 1 Throttle shear 1.0 6 60 3 Comparative Example 2 Planetary agitator for 30 minutes - - - 4 Comparative Example 3 Planetary agitator 120 minutes - - - 5 As can be seen from Table 4, In the case of Comparative Example 1 in which pretreatment dispersion was carried out using a nozzle having a thick orifice having a orifice diameter of 1.0 mm, the gloss of the coating film was 3, which was compared with Comparative Example 2 in which the mixture was stirred by a planetary mixer. 3 o'clock the same 34 100113117 201207083 mixed state. Further, it was found that when the time of mixing and stirring with the planetary mixer was set to 30 minutes and 12 G minutes, there was no large change in the coating gloss. On the other hand, it can be seen that in the case of using a nozzle having a throttling aperture to avoid a five-axis orifice, when the lamp is processed to disperse, the coating gloss is increased to 32', which is better than the conventional use of the mixing. The mixing of the machine is processed, and the mixing effect is high. Thus, when the mechanical shearing force at the time of dispersing the pre-treatment with a throttle orifice of 〇.5_ is greater than that of a nozzle using a throttle orifice 丨〇mm or a conventional use of a scrambler for pre-treatment dispersion, The difference in gloss indicates that the wettability of the surface of the dried film is remarkably improved. [Effect of the second step on the adhesive properties] The actual ratio r which is not used in the dispersion processing of the second step in Table 5, and the comparative example 4 which is implemented by the conventional method using the 3 machine method The adhesive property of 5 is clear to the adhesiveness of the rubber under the condition of the dispersion treatment of the second step using a high-pressure homogenizer.

100113117 35 201207083 [Table 5] Step 1: Pre-dispersion treatment Step 2: Dispersion treatment of paste characteristics Method Method Throttle aperture [mm] Treatment pressure [MPa] Passing times [times] Conductive paste temperature [°C] Viscosity [Pa · s] Surface roughness Ra [/mi] DFD [g/cm3] Example 2 Throttle shear high pressure homogenizer 0.19 100 1 60 27 0.26 5.8 Example 3 Throttling shear high pressure homogenization 0.19 100 3 60 24 0.24 6.0 Example 4 Throttle shear high pressure homogenizer 0.19 100 5 60 24 0.24 6.0 Comparative example 4 Planetary mixer 3 roller machine - - - - 32 0.28 5.6 Comparative example 5 Throttle cutter Cutting 3 Roller - - - - 30 0.27 5.6 As shown in Table 5, when comparing the viscosity of the conductive paste which was subjected to the dispersion treatment using the high-pressure homogenizer and the 3-roller in the second step, it is known that the viscosity is used. When the number of passes of the high-pressure homogenizer (the number of times of dispersion processing) is one time, it is 27 Pa·s (see Example 2 below), but the number of times of treatment is increased to three times (hereinafter referred to as Example 3) or five times ( When referring to Example 4) below, the viscosity was lowered to 24 Pa·s. This is because the high shear force of the high pressure homogenizer increases the dispersibility of the nickel powder or ceramic powder. In addition, the surface roughness and the DFD are 0.26/xm and 5.8 g/cm3 if it is treated once, but when the number of times of treatment is increased to 3 or 5 times, it becomes 0.24/mi and 6.0 g/cm3, thereby also It is known that the dispersibility of the nickel powder or the ceramic powder is improved. However, the viscosity of the conductive paste produced by the 3-roller is significantly higher than that of the conductive paste produced by the high-pressure homogenizer, and the surface wetting is poor because the shear of the 3-roller is weak, so nickel Powder or ceramic powder cannot be fully dispersed,

100113117 36 S 201207083 is the result of poor surface roughness or DFD. Further, even in the case where the nozzle having the orifice diameter of 〇5 mm was used for the pretreatment dispersion by the orifice shearing under the same conditions as in Examples 2 to 4, the dispersion treatment was carried out by the 3-roller (refer to the comparison). Example 5) also showed the result of poor dispersion of nickel powder, surface roughness or poor DFD. The viscosity change rates of Comparative Examples 4 and 4 which were not subjected to the dispersion treatment of the second step using the high pressure homogenizer in Table 6 were compared with those of Comparative Examples 4 and 5 which were carried out by the conventional 3 roll method. [Table 6] Step 1: Pre-dispersion treatment inflammation 2 steps: Dispersion treatment of viscous rate [%1 method method initial 1 length 10 夭 30 夭 Example 2 orifice cutting shear orifice shear homogenizer high pressure Chemer 0 0 5 3 7 9 Example 3 6 7 Example 4 Known orifice shear to pressure homogenizer 0 λ 6 6 Comparative Example 4 Planetary mixer. 3 Roller 〇 13 27 30 Comparative Example 5,! _ — orifice cutting 3 roller machine 0 11 23 25 ——__3 roller machine ^ 〇|n| 23 butyl 75- Because the use of high-pressure homogenization H of the embodiment improves the surface of the board, dampness Moreover, the surface dispersibility is obtained, whereby the dispersing agent is adsorbed on the surface of the teaching surface to prevent the particles from re-aggregating, and the conductive adhesive_dispersion stability can be maintained even after storage for 3 days, so the viscosity change rate is small. However, in the dispersion treatment of the second step, the conductive pastes of Comparative Examples 4 and 5 of ❹3_ were poor in particle size_"dragon", and the dispersibility was also low, and (4) the dispersing agent was not effectively (10) on the surface of the particles. Therefore, ^ can be transferred to dispersion stability, and the viscosity change rate is large. [Influence of Dispersion Treatment in First Step and Second Step] 100113117 37 201207083 The effect of the combination of the dispersion treatment in the first step and the second step on the adhesive properties is shown in Table 7, and the influence on the viscosity change rate is shown in Table 8. [Table 7] $13⁄4: Diffusion treatment Step 2: Dispersion treatment of paste characteristics Method Method Throttle aperture [mm] Treatment pressure [MPa] Pass times [times] Conductive paste temperature rc] Viscosity [Pa · s] Surface Thickness Ra Γ i/ml DFD [g/cm3] Example 5 Throttle Shear High Pressure Homogenizer 0.13 250 5 60 20 0.18 5.8 Example 6 Throttle Shear High Pressure Homogenizer 0.09 250 10 60 25 0.12 5.7 Comparative Example 6 Shixing Stirrer J Roller - - - - Bu 28 0.22 5 5 Comparative Example 7 Planetary Stirrer High Pressure Homogenizer 0.09 250 10 60 28 0.14 5.6 [Table 8] Step 1: Before Dispersion treatment Step 2: Dispersion treatment ------_ Viscosity change rate [%] Method method Initial 1 day 10 days fly 0 Proper Example 5 Throttle shear high pressure homogenizer 0 5 7 7 Example 6 Flow hole shear high pressure homogenizer 0 4 7 Q Comparative example 6 Planetary agitator 3 roller machine 0 15 26 0 Comparative example 7 Planetary agitator High pressure homogenizer r 〇12 19 24 It can be seen from Table 7 'Implementation of the use of the prior art The conductive paste produced by the pretreatment dispersion of the scrambler and the dispersion treatment by the 3-roller (refer to Comparative Example 6) is The surface wetting is inferior to the conductive paste produced by the high-pressure homogenizer shown in Examples 5 and 6, and the shear of the 3-roller is weak, so that the nickel powder or the ceramic powder cannot be sufficiently dispersed, and the surface is not sufficiently dispersed. The roughness or DFD is poor, and the viscosity change rate is also large. On the other hand, as is clear from Table 8, a conductive paste prepared by a pretreatment dispersion using a stirrer and dispersed by a high pressure homogenizer is implemented (refer to 100113117).

S 38 201207083 According to Comparative Example 7), compared with the conductivity of the crucible in Example 6 which was subjected to high > 1 homogenization under the same conditions, the surface of the particle was poorly wetted, and the separation was performed/ The difference in the amount of the raw material is not sufficiently adsorbed on the surface of the particles, and the re-aggregation of the particles cannot be prevented. Therefore, the dispersion stability of the conductive paste is poor, so that the rate of change in viscosity becomes large. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a flow chart showing the manufacture of a conductive paste in accordance with the present invention. Fig. 2 is a schematic cross-sectional view showing a nozzle having an orifice used in the pretreatment dispersion step of the i-th step. Fig. 3 is an explanatory view of a dispersing device used in the pretreatment dispersion step of the first step. Fig. 4 is a graph showing the relationship between viscosity and paste temperature. [Main component symbol description] 1 Slot 2 Heater 3 Stirring paddle 4 Pump 5 Nozzle 6 Throttle hole D Nozzle diameter (outer diameter) L Distance between orifices D Throttling hole (inner diameter of orifice) 100113117 39

Claims (1)

201207083 VII. Patent Application Range: 1. A method for producing a conductive paste, comprising the following first steps to third steps: [First step] comprising at least a conductive metal powder, a dispersant, The conductive binder of the organic binder and the organic solvent is mixed and heated while being heated, and then passed through a nozzle having an orifice to perform a dispersion treatment before the dispersion treatment; [2nd step] will be carried out in the first step a step of dispersing the pre-processed and dispersed heated conductive paste by a high-pressure homogenizer; [Step 3] The conductive paste which has been subjected to the dispersion treatment in the second step is filtered by a filter, The steps. 2. The method of producing a conductive paste according to the first aspect of the invention, wherein the nozzles having the orifices in the first step are arranged in series or more in series to disperse the conductive paste. 3. The method for producing a conductive paste according to the first aspect of the invention, wherein the orifice of the orifice of the first step has a orifice diameter of 0.2 to 0.5 mm. 4. The method for producing a conductive paste according to the first aspect of the invention, wherein the conductive paste has a viscosity of 10 Pa·s or less. 5. The method for producing a conductive paste according to claim 1, wherein the high pressure homogenizer is subjected to a dispersion treatment at a pressure of 50 to 250 MPa. 6. The method for producing a conductive paste according to the first aspect of the invention, wherein the orifice of the second high-pressure homogenizer in which the conductive paste of the second step flows is throttled The aperture is 〇.〇5~〇.2mm. 7. The method of producing a conductive paste according to the first aspect of the invention, wherein the high-pressure homogenizer comprises a cooler at an outlet portion side of the orifice. 8. The method for producing a conductive paste according to claim 1, wherein the heated conductive paste in the second step has a viscosity of 10 Pa·s or less. A conductive paste formed by the method for producing a conductive paste according to the first aspect of the invention, characterized in that the content of the conductive metal powder is 30 to 70% by weight based on the total amount of the conductive paste. . 10. The conductive paste of claim 9, wherein the conductive paste comprises ceramic powder as a sintering inhibitor. 100113117 41