TW201100184A - Composite copper particle - Google Patents

Abstract

The present invention relates to a composite copper particle, comprising a parent particle of copper having an average particle diameter of 0.2-10 μm, which contains therein a plurality of inorganic oxide particles having an average particle diameter of 5-50 nm. The inorganic oxide particles include particles that are completely embedded in the parent particle near the surface thereof and particles that are embedded in the parent particle in a condition of being partially exposed on the surface of the parent particle. The content of the inorganic particles is 0.1-5wt% relative to the total weight of the composite copper particle.

Description

[Technical Field] The present invention relates to a composite copper particle in which a plurality of oxide particles are contained in a mother particle containing copper. [Prior Art] A fluidity composition in which a conductive paste is dispersed in a medium containing a resin-based binder and a solvent, and is widely used for forming an external electrode for forming an electron capacitor or the like. s

As the above-mentioned conductive paste, there is a high-temperature calcined conductive paste which is ensured to conduct by high-temperature calcination by volatilizing an organic component and sintering a conductive filler. The high-temperature stewed conductive adhesive is generally a paste-like composition in which a conductive filler represented by metal particles and a glass frit are dispersed to an organic medium, and is relatively high in temperature due to about ~_°c. The calcination is carried out to volatilize the organic vehicle, and the conductive material is ensured by sintering the conductive filler. At this time, the glass frit has a function of causing the conductive film to follow, and the organic solvent functions as an organic medium for making the metal powder and the glass frit printable. The high-temperature calcined conductive paste cannot be used for a printed wiring board or a resin material because of its high calcination temperature. However, it can be integrated by magnetization to achieve low resistance, and is currently used, for example, for external electrodes of laminated ceramic capacitors. . Further, as the metal particles used for the conductive paste, various particles obtained by combining metal particles to be a base material and inorganic oxide have been proposed. For example, Patent Documents 丨 and 2 describe copper particles in which the surface of the copper particles is covered with Μ%. According to these documents, 146549.doc 201100184 conductive paste containing copper powder containing the copper particles is excellent in oxidation resistance and sinterability. However, there has been no research on the improvement of the heat shrinkage resistance at the time of sintering. In addition to the above-mentioned technique, the present applicant has obtained an inorganic oxide layer formed by forming an inorganic oxide layer on the surface of the powder of the metal powder in order to improve the heat shrinkage resistance of the metal powder and obtain a conductive circuit excellent in dimensional stability. Metal powder (refer to Patent Document 3). The inorganic oxide layer is composed of cerium oxide or aluminum oxide. The metal powder is copper powder or silver powder. The inorganic oxide layer is formed by fixing the inorganic oxide to the surface of the powder of the metal powder by mechanochemical method. However, the required properties of the metal particles for the conductive paste, particularly the high-temperature calcined conductive paste, are increasingly required. Strictly, the heat shrinkage resistance is also sought to be further improved. [Patent Document 1] Japanese Patent Laid-Open Publication No. Hei. No. Hei. No. 2008-101276 (Patent Document 3) Japanese Patent Laid-Open Publication No. Hei No. Hei. No. 2004-84069. The object is to provide a composite metal particle having various properties which are further improved than those of the prior art described above. The present invention provides a composite copper particle characterized in that it is a composite of inorganic oxide particles having an average particle diameter of 5 to 50 nm in a mother particle containing steel having an average particle diameter of 0.2 to H. The copper particles and the inorganic oxide particles include those which are completely embedded in the vicinity of the surface of the female puller and are embedded in the mother particle T in a state in which a part of the surface of the mother particle is exposed and exposed, 146549.doc 201100184 inorganic oxide The particles are 0·1 to 5 wt%. The content of the composite metal particles is the same as that of the composite copper plate as a whole, and is a method for producing the composite copper particles described above, and/or a copper ion-containing or copper-containing ion. Water-based liquid of copper oxynitride and inorganic oxide particles dare to add::::: The step of reducing copper,

G 添加 In the reduction of copper, 'incorporating inorganic oxide particles other than those present in the initial aqueous liquid, or adjusting the enthalpy value of the liquid in the reduction of copper to a range of 7.5 to 12 [Embodiment] Hereinafter, based on the present invention The preferred embodiment will be described. The composite copper particles of the present invention are composed of a composite comprising copper mother particles and inorganic oxide particles. The inorganic oxide particles are smaller in particle diameter than the mother particles. The inorganic oxide particles contain a plurality of particles in the mother particles. The presence of the inorganic oxide particles in the composite copper particles has a characteristic. Specifically, the inorganic oxide particles include at least two types: (a) completely embedded in the vicinity of the surface of the mother particle, and (b) embedded in the mother particle in a state in which a part of the surface of the mother particle is exposed. When the inorganic oxide particles are present at such a position, for example, when a conductor containing a slurry containing composite copper particles or the like is sintered, it is possible to control the heat shrinkage start temperature and the heat shrinkage speed of the composite copper particles. The reason is as follows. By the presence of the inorganic oxide particles of (B), the composite copper particles are prevented from being fused to each other during sintering, and the heat shrinkage starting temperature is increased. About heat 146549.doc 201100184 ίShrinking speed 'passing f After the beginning of copper melting, the heat shrinking speed will instantly pick up the door. In the present invention, the presence of (曱) inorganic oxide particles will cause the furnace knot to shrink. The quasi-γ A z„ 70 ^ τ is again hindered, thereby suppressing the heat shrinkage rate. Based on the composite copper particles according to the present invention such as X, the heat shrinkage can be easily controlled at the time of sintering. In the technique 1 described in the recognition, since the state of si〇2 exists only on the surface of the steel particles, the heat shrinkage is not inhibited after the start of the fusion, and thus the heat shrinkage is instantaneously performed. This phenomenon is used for the electrode. When it is formed, it is a cause of cracking or peeling. The technique described in Patent Document 3 is similar to Patent Documents 1 and 2, in which heat shrinkage is instantaneously started after melting. If the particles are not crystallized by high heat treatment, sufficient heat shrinkage resistance may not be obtained. The inorganic oxide particles in the composite copper particles, as described above, include (曱) fully embedded in the mother particles. At least two types of the inorganic oxide particles of (a) are embedded in the surface of the parent particle in the vicinity of (b) a part of the surface of the mother particle is exposed, and the inorganic oxide particle of (a) is completely embedded in the vicinity of the surface of the mother particle. "Inorganic oxide particles are mainly present in the following regions, that is, when the radius of the mother particles is r, the outer region of r/3 or more based on the center position of the mother particles, and from the surface of the parent particles to the inorganic The inner region above the oxide particle diameter. This state can be confirmed by exposing the cross section of the composite copper particles by fib treatment, and observing it by TEM, and performing elemental analysis using EDS. On the other hand, the inorganic oxide particles of (B) "the state in which a part of the surface of the mother particles is exposed" means that the diameter of the inorganic oxide particles is based on the diameter of the inorganic oxide particles, preferably 55 to 90%. The status of doc 201100184. By embedding the money oxide particles in the mother particles to such a degree, when the composite steel particles are used, for example, as (4), it is difficult to apply the shear force at the time of the step (10). The beneficial effect of the inorganic particles falling off from the parent particles. Further, by not completely embedding all of the inorganic oxide particles in the mother particles, the surface of the copper can be prevented from being completely exposed, and the heat shrinkage resistance can be improved. 〇〇 In terms of heat shrinkage and heat shrinkage, the ratio of the inorganic oxide particles of (a) to the inorganic oxide particles of (b) in the composite steel particles, the weight ratio is preferably (A) ): (B) = 1: 9~8: 2, especially good 4: 6~6: 4. This ratio can be obtained by the following method. First, a liquid which does not dissolve steel and dissolves inorganic oxide particles is prepared. In the case where the inorganic oxide particles are particles of, for example, Si 2 , an aqueous solution of sodium hydroxide having a concentration of mol/L or more can be used. In the case where the inorganic oxide particles are particles of 乂2〇3, the particles of Al2〇3 can be recombined by using an aqueous solution of 2 nm in a concentration of 9 mOl/L or more and heating to a sail or more. In the case where the inorganic oxide particles are particles of Ti 2 , a hydrofluoric acid aqueous solution of 2.7 mol/L or more can be used. The composite copper particles are introduced into the liquid to dissolve the inorganic oxide particles exposing the surface of the particles. : Injecting composite copper particles with respect to liquid 5GG mL 2g The dissolution of inorganic oxidized particles is carried out, for example, at a temperature of 25 to 3 〇t for about (9) minutes (except for A1 particles except for lcp (inductively_c(>upled pi_, The amount of the inorganic oxide particles dissolved in the liquid is measured, and the amount of the inorganic oxide particles on the surface of the composite copper particles is determined. '', and the composite copper particles are separated from the liquid. And put it into the soluble copper solution 146549.doc 201100184 body (for example, an aqueous solution of mineral acid such as nitrate) to completely dissolve the copper. Then add an agent capable of dissolving the inorganic oxide particles to the liquid (for example, inorganic oxide particles are dead) In the case of Sl° 2, 'is a hydrofluoric acid aqueous solution', the inorganic oxide particles are widely dissolved. Thus, the linear body is obtained as a target for ICP analysis, and the inorganic oxidation completely embedded in the mother particles is obtained. From the results of the study by the inventors of the present invention, it has been found that the control of the shrinkage of the composite copper particles is determined by the size of the inorganic oxide particles. In detail, the inorganic oxide having a larger particle diameter The particle size of the particles is larger than that of the smaller particle size, so that the melting is less likely to occur, and the higher the melting temperature of the inorganic oxide puller from the body, the higher the melting temperature of the mother particle. Therefore, by controlling the particle diameter of the inorganic oxide particles, the heat shrinkage initiation temperature of the composite copper particles can be controlled. From this point of view, the average particle diameter of one of the inorganic oxide particles-human particles is preferably set to 5 to 5 G nm. Preferably, the average particle diameter is determined by (4) or a particle size distribution measuring device. When the particle size of the inorganic telluride particles is as described above, in the relative relationship with the diameter of the parent particles, The particle size of the inorganic oxide particles is preferably such that the mother particles are finer than 1/2 (Μ/ι(9), even if the material particles and the mother particles are smaller in tb, which also helps to control the shrinkage of the composite copper particles. Corresponding to this, the average particle diameter of the parent particle - the secondary particle is -0.2 to 10 μιη, preferably 〇3 to 5 _. If the mother is less than 0.2 _, the mother particle The size is too close to the inorganic oxide particles ^^, resulting in the conductive of the composite copper particles On the other hand, when the average particle size of the mother particles exceeds 146549.doc 201100184, the sintering temperature of the mother particles increases, so it becomes unnecessary to use inorganic oxide particles. The diameter can be measured in the same manner as the method for measuring the average particle diameter of the primary particles of the inorganic oxide particles. • The inorganic oxide particles of the above-mentioned fine particles can be produced by the hydrolyzable inorganic compound (tetra) solution or polycondensation to produce an inorganic oxide sol. For example, in the case of a sol that is called a township, the following method may be employed: water-based and acid-neutralization or ion exchange; and S1〇2 sol is obtained by the solution of tetrachlorite The method described in Japanese Laid-Open Patent Publication No. Hei 6-316407. In the case of obtaining a sol of Al2〇3, the following method may be employed: a method of producing a metal directly by reacting with water in the presence of a general acid such as an inorganic acid or an organic acid; or Japanese Patent (4) Ping 5_24824 The method described in the bulletin. In the case of obtaining a sol, the following method may be employed: a method of contacting an aqueous solution of a titanium salt with an anion exchanger; a method of neutralizing by adding an ammonia water; a method of adding an aqueous solution of niacin or the like; or a Japanese patent The method described in JP-A No. 8 (10). In the case of obtaining the sol of (10), the following method can be employed: after the reaction salt is reacted with the test substance in a predetermined molar ratio in an aqueous medium to form a hydroxide suspension, Under 10~95. (: A method of oxidizing an oxygen-containing gas to be oxidized; or a method described in JP-A-2002-326812. In the case of obtaining a sol of palpitations 2, the following method can be employed. Adding a base to an aqueous solution of a cerium salt to obtain cerium zirconium oxide, and then hydrolyzing the oxidized water; adding an aqueous alkali solution to the aqueous solution of the wrong compound in the presence of a few acids or a base acid to obtain a oxidized hammer gel The dispersion liquid, the method of hydrothermal treatment of the I46549.doc 201100184 'knife discharge liquid super m and deionization by ion exchange resin; or the method described in Japanese Patent No. 2_.29_6. The control of the heat shrinkage rate of the copper particles is determined by the amount of inorganic oxide particles contained in the composite copper particles. As described above, generally, the heat shrinkage rate of the copper particles immediately increases after the start of melting, due to By including an appropriate amount of the inorganic oxide particles, the increase in the heat shrinkage rate can be suppressed, so that the shrinkage can be progressed slowly. From this point of view, the content of the inorganic oxide particles is relatively high. The composite copper particles as a whole are preferably 〜1 to 5% by weight, and more than 0.2 to 3% by weight. If the content of the inorganic oxide particles is less than 5%, the inorganic particles are not available on the surface of the mother particles. The oxide particles completely cover the step or the kinking portion as the easily sintered portion. Conversely, if the inorganic oxide particles are transferred to the heat of the tongue and the cerium is more than 5%, the helmet oxide is used as the insulator. The amount of increase will cause the conductivity of the composite steel particles to decrease, and thus become unsuitable for use in electronic materials. The content of inorganic oxide particles in the composite copper particles can be obtained by dissolving the composite copper particles and utilizing the 1CP described above. In addition, when the sintering of the composite copper particles is instantaneously performed, the sintered body is likely to be cracked, and there is a problem that it is easily peeled off from the substrate. Further, there is a problem that sintering The temperature is narrow, the operability is poor, and the calcining base (4) is difficult, and the manufacturing cost is increased. As described above, the thermal shrinkage of the composite copper particles during sintering is important. The inorganic oxide particles on the surface of the t-shaped particles, & inorganic oxide particles completely embedded in the vicinity of the surface of the composite copper particles. In other words, U6549.doc -10- 201100184 even if the core region of the mother particles exists in the helmet The nourishment of the ceremonial particles and the nomination of the heat-resistant shrinkage of the composite copper particles. For this point of view, it is better that the central region of the parent particle is 蜇{_ π I , ^ there is no inorganic Oxide grain h Here, the "heart area" is roughly the area from the center of the mother particle to within 1/3 of the radius. The surface of the composite steel particle is preferably composed of copper and inorganic oxide particles. In other words, the surface of the composite copper particles is preferably Ο

It is not composed only of inorganic oxide particles. According to this configuration, the electrical contact between the composite copper particles can be reliably performed, and the decrease in the electrical conductivity of the sintered body can be suppressed. As the inorganic oxide particles, an oxide of a metal element or a non-metal element can be used. The inorganic oxide particles are preferably those which form a (10) base on the surface in an aqueous test solution having a pH of mainly 7.5 to 12 (the reason is that it is preferably at least a part of the soluble in the following description) In the alkaline aqueous solution, and by the dissolution thereof, a base can be generated on the surface. As a preferred specific example of the inorganic oxide particles, the particles of the oxide of the metal element may be exemplified by alumina (Al 2 〇 3 ), titanium oxide. (Ti〇2), cerium oxide (Ce〇2), cerium oxide (ZrO 2 ), etc.; the particles of the oxide of the non-metal element include cerium oxide (SiO 2 ), etc. The shape of the inorganic oxide particles is not in the present invention. In particular, inorganic oxide particles having a spherical shape, a polyhedral shape, a needle shape, a spindle shape, a flat shape, or a ginkgoose shape can be used. In general, by using an inorganic telluride particle having an isotropic shape, For example, the spherical inorganic oxide particles can obtain satisfactory heat shrinkage resistance. 146549.doc -11· 201100184 Further, the shape of the mother particles is not particularly limited in the present invention, and can be similar to the inorganic oxide particles. For example, a spherical shape, a polyhedral shape, a needle shape, a spindle shape, a flat shape, a gold flat sugar shape, etc., generally, a spherical or flat shape is used, and the mother particle contains copper. Alternatively, the mother particle It can also be a copper alloy. In the composite copper particles, the mother particles are sufficiently larger than the inorganic oxide particles, so the shape of the composite copper particles is substantially the same as the shape of the mother particles: The diameter is also substantially the same as the diameter of the parent particle. # Next, a description will be given of a preferred method for producing composite copper particles. The composite steel particles can be suitably produced by the following method: the method has an ion species containing: ions or containing copper And a step of adding a reducing agent to the aqueous solution of copper oxide or copper oxychloride and inorganic oxide particles to carry out reduction of copper. That is, it can be suitably produced by wet reduction of copper. The liquid can be, for example, an aqueous solution of a water-soluble copper salt such as sulfuric acid steel, vaporized copper, copper acetate or copper nitrate, or copper oxide such as copper oxide or copper hydroxide (Cu ( h) 2) An aqueous slurry of the equivalent compound. In the case of either aqueous solution or water-based material, the concentration of copper contained in the liquid is preferably G"~5 mGi/L, especially = It is 1 to 3 mol/L. The liquid is mixed with the inorganic oxide particles. It is particularly preferable to mix the inorganic oxides in the sol state in terms of the uniform distribution of the inorganic oxide particles in the mother particles. The content of the inorganic oxide particles obtained in this manner is preferably (10) mg relative to copper 1 g', and particularly preferably is 5 〇. Adding reduction to the 146549.doc 201100184 T mixture The agent is used for reduction of copper. As a reducing agent, for example, sugar can be used, etc. Reduction d W, potassium quaternary acid, dimethylamine (IV), reduction, control of particle size and shape of the mother particles, (4). As such (4), for example, (4) a water-soluble breaking compound or the like can be used. The oxygen oxime method is to pre-exist the inorganic cerium particles in the reaction system before the reduction of copper and to carry out the copper in the presence of the inorganic oxide. (4) By using such conditions, the inorganic oxide particles can be specifically adsorbed in the ^ In the process of the growth of the mother particles, kinks (portions of the surface appearing) or steps (portions where the monoatomic layer of the surface forms a step) are sometimes generated. As a result, the unstable portion in the mother particles is selectively protected by the inorganic oxide particles, and the heat shrinkage at the time of sintering is controlled. "It is used as an inorganic oxide particle. If it is used in the surface of an aqueous solution, a sulfhydryl group is formed, and the inorganic oxide particle and the sulfhydryl group adsorbed on the mother particle are bonded by a hydrolysis reaction to cause inorganic It is preferable that the oxide particles easily enter the inside of the mother particles. By reducing the particle diameter of the mother particle formed (the particle diameter is substantially equal to the particle diameter of the complex U copper particles) and the shape, for example, the enthalpy value or temperature of the above-mentioned mixture 9 or the addition rate of the reducing agent or Concentration and the like are easily controlled by two lines. In the present production method, a method in which the inorganic oxide particles are completely embedded in the vicinity of the surface of the mother particle containing copper and the inorganic oxide particles are partially exposed to the surface of the mother particle is preferably used. Yes: 146549.doc -13- 201100184 Do as follows (1) or (7). The operations of (1) and (7) can be combined separately. j can be operated as early as possible, (1) in the coexistence of inorganic oxide particles, fCu2 + v» ^ Adding a reducing agent to form copper ions to form CU2 〇, then adding a reducing agent to regenerate the CM to form Cu 'At this time, other than the one existing in the aqueous liquid) y inorganic oxide particles (preferably dissolved in inorganic oxide particles)

The process of producing the composite copper particles of the present invention by the operation (1) will be described based on the image schematically represented in Fig. 1. Further, in Fig. 2, although Si 2 is used as the oxide particles of the autumn I machine, the reaction proceeds in the same manner when the inorganic oxide particles other than the above are used. Further, in the following description, there is a part which has not been fully elucidated, and a part is speculated by the inventors and the like. First, as shown in Fig. Ua, Si 2 particles are coexisted in an aqueous liquid containing a copper source (not shown). After the addition of the reducing agent in this state, as shown in the figure, copper ions (Cf) are reduced to form Cu2 ruthenium particles. During the generation of the particles, the Si 〇 2 particles present in the liquid enter the Cu 2 〇 particles.

The Si〇2 particles are also present in the liquid, and no nuclear particles have been formed at this time. Next, Si〇2 particles are additionally added to the system in addition to those present in the initial system, and then a reducing agent is added to the system again. By adding a reducing agent again, as shown in Fig. 1(C), Cu2 ruthenium particles are dissolved and become small, and Cu core particles are formed in the system. Since the nucleus of Cu is relatively different in crystal density, unlike the CuW particles, the Si 〇 2 particles do not enter the nucleus of Cu 146549.doc • 14- 201100184. After the reduction of the Cue particles by the action of the reducing agent, as shown in Fig. 1(d), the ChO particles are further dissolved, the particle diameter thereof is decreased, and the core particles are grown. At this time, if the particle diameter of the ChO particles is decreased, the specific surface area is increased, and the dissolution rate is also increased. As a result, since the amount of Cu ions dissolved in the system increases, the growth rate of the core particles increases. Since the growth rate of the core particles of Cu increases, the crystal density of the core particles of Cu decreases. 〇2 particles begin to enter the cu particles. ❹ If the Si〇2 particles enter the Cu particles, as shown in Figure 1(e), in the liquid -

The amount of Si〇2 particles is gradually reduced. At the same time, however, the dissolution of the Cu2 ruthenium particles is also carried out, so that the dissolution is carried out to replenish the Si 〇 2 particles into the liquid. From this, it is confirmed that the Si 〇 2 particles entering the Cu particles are mainly Si 〇 2 particles existing in the liquid at the initial stage of entry, and the Si 〇 2 particles are mainly completely embedded in the composite copper particles. Further, as the Si 〇 2 particles continuously enter, the Si 〇 2 particles released from the Cu 20 particles start to enter the Cu particles, and the particles are embedded in the Cu particles in a state in which the composite copper particles are partially exposed. At the initial stage of entry, the 〇2 particles present in the Q liquid are mainly the SiO 2 particles added for the second time. On the other hand, the Si〇2 particles released from the ChO particles are mainly Si〇2 particles added to the liquid at the initial stage of production. Therefore, by completely balancing the amount of Si〇2 particles initially added to the liquid and the amount of the Si〇2 particles added to the second, the fully embedded Si〇2 particles can be controlled to be partially exposed.

The amount of Si〇2 particles. Thus, as shown in Fig. £ (£), the target composite copper particles can be obtained. Operation (2) Under the coexistence of inorganic oxide particles, the pH value of the liquid of 146549.doc -15- 201100184 in the reduction of copper ions (Cu2+) is checked. Specifically, it is preferable to adjust the pH to 7.5 to 12', and it is more preferable to adjust the pH to 8 to 11. Further, the reducing agent is added after the pH of the liquid is adjusted to the range. In the reduction reaction, the pH of the reaction system starts to decrease, and the test substance is further added to maintain the pH within the above range. By maintaining the pH of the reaction system within the above range, an OH group is present on the surface of the core of the copper particles formed by the reduction, and the 〇H group attracts the inorganic oxide particles. The nucleus of the copper particles undergoes grain growth while attracting the inorganic oxide particles, so that the inorganic oxide particles enter the mother particles of copper. Of course, the surface of the mother particle ◎ will also adsorb inorganic oxide particles. At this time, the system? The higher the value of 11 is, the more the OH group is present, so that the inorganic oxide particles easily enter the interior of the mother particle. That is, by control? A value of 11 controls the amount of inorganic oxide particles that are introduced. The process of producing the composite copper particles of the present invention by the operation (2) will be described based on the image schematically represented in Fig. 2. Further, in Fig. 2, Si 2 is used as the inorganic oxide particles, but in the case of using inorganic oxide particles other than the above, the reaction proceeds in the same manner. In addition, the following description of the part that has not been fully explained is a part of the speculation of the inventors and the like. First, 8 丨〇 2 particles are coexisted in an aqueous liquid containing a copper source (not shown): After the reducing agent is added in this state, as shown in Fig. 2 (4), the copper ion ' (u ) is reduced to generate CU2 〇 particle. The Si〇2 particles present in the liquid during the formation of the 2〇 particles enter the CU2〇 particles. It is called a particle: it is in a liquid... At this time, no nuclear particles of Cu have been formed. After the reduction is continued by the addition of a reducing agent, as shown in Fig. 2(b), 146549.doc •16-201100184, the Cu2 cerium particles which are not formed in the daytime are dissolved and become smaller, and nuclear particles of cu are generated in the system. Since the nucleus particles have a high crystal density, unlike the wo particles, the si 〇 2 particles do not enter the core particles of Cu. After the reduction of the cu2 粒子 particles is further carried out, as shown in Fig. 2(c), the Cu 2 ruthenium particles are further dissolved, the particle diameter thereof is decreased, and the core particles of Cu are grown. At this time, if the particle diameter of the ChO particles is decreased, the specific surface area is increased and the dissolution rate is also increased. As a result, since the amount of Cu+ ions dissolved in the liquid increases, the growth rate of the core particles of Cu also increases. As the growth rate of the Cu nucleus particles increases, the crystallization density of the Cui core particles decreases, and the Si 〇 2 particles begin to enter the Cu particles. The inventors of the present invention considered that the mechanism for causing Si 2 particles to enter the Cu particles is as follows. That is, as shown in Fig. 2(d), the particles are in a growth process in which the particles have an OH group on the surface thereof. On the other hand, since it is alkaline in the liquid, OH groups are also present on the surface of the Si 2 particles. Therefore, the oh group on the surface of the Cu particles and the 〇H group on the surface of the Si 2 particles are hydrolyzed to attract the two particles to each other. By this, the Si 〇 2 particles are allowed to enter the Cu particles. Therefore, the more the number of OH groups on the surface of the si 〇 2 particles, the easier the Si 〇 2 particles enter the Cu particles. As the growth of Cu particles, the pH value of the liquid gradually decreases, as shown in Fig. 2(e), the pH of the liquid is maintained in the range of 7_5 to 12 by adding an inert substance, thereby maintaining the Si〇2 particle. The number of OH groups on the surface. Thereby, the degree of entry of the Si 〇 2 particles can be prevented from being lowered. That is, by adjusting the pH of the liquid, the degree of entry of the SiCh particles can be controlled, and the amount of the completely embedded Si 2 particles and one of the exposed Si 2 particles can be controlled. Thus, the target composite copper particles can be obtained as shown in Fig. 2(f). 146549.doc -17- 201100184 By the above operations, the amount of the complete particles and the partially exposed inorganic oxide particles can be precisely controlled, and the advantages of the sintering behavior of the obtained composite copper particles are precisely controlled. In the composite copper particles obtained in this way, the pro-ceramic oxide particles partially exposed on the surface thereof are reliably held on the mother particles by the anchoring effect or the like, so even if the composite is to be mechanically stretched, please pick up De-alloying of inorganic oxide particles. Therefore, even if the composite copper particles obtained are subjected to, for example, pressure, they are processed into a flat shape, and the fall of the inorganic oxide particles during processing can be prevented. The composite copper particles obtained can be mixed, for example, with a glass (tetra) end and an organic vehicle. The conductive (4) is an external electrode of a laminated ceramic electronic component such as a ceramic pot. In particular, it can be used to form an external electrode that is electrically connected to an internal electrode that is recorded as a main component. In the formation of the external electrode, the conductive paste is applied to the outer surface of the laminated ceramic electronic component body made of ceramic, and then sintered by heat treatment at a high temperature (for example, 400 to 1000 t:). In this case, when the conductive paste containing the composite copper particles of the present invention is used, the heat shrinkage of the coated body during sintering can be controlled, so that the sintered body generated by sintering can be effectively prevented from being peeled off from the body of the part, or in the sintered body. Cracks appear on it. [Examples] Hereinafter, the present invention will be described in more detail by way of examples. However, the scope of the invention is not limited to the related embodiments. If there is no special provision, "%" means "% by weight". [Example 1] 146549.doc -18- 201100184 First, 9 L of a copper sulfate aqueous solution of 3_6 Torr was heated at 50 ° C, and a SiO 2 sol was added to the copper sulfate aqueous solution (sol concentration 20%, average particle diameter 5 nm) ) 50 g. Thereafter, 13% of an aqueous ammonia solution having a concentration of 25% was successively added, and the concentration was 25°/. The aqueous sodium hydroxide solution was 425 〇 g. Here, 450 g of hydrazine monohydrate (lanthanide reducing agent) and an aqueous ammonia solution (concentration: 25%) as a pH adjuster were continuously added at 591 m, while maintaining the pH of the liquid at the side of the crucible to obtain a cuprous oxide slurry. (first reduction treatment). Then, in order to complete the reduction reaction, the stirring was continued for further 30 minutes. Ο 添加 To the cuprous oxide slurry, hydrazine monohydrate (lanthanide reducing agent) 3 〇〇 g is added. Further, the mixture was stirred for 60 minutes to completely carry out the reduction reaction, and the target composite copper particles were reduced and precipitated (the second reduction treatment was carried out for the second time, and the pH of the system was gradually lowered after the second addition of the hydrazine monohydrate (lanthanide reducing agent). In order to make "... the sol enters stably, add 5% aqueous sodium hydroxide solution to adjust the pH of the system to 11. The composite copper particles obtained by filtration cleaning (in this case, adding citric acid as a surface treatment agent) After that, it is subjected to (four), heating and drying for 5 hours, and then subjected to grinding treatment. The obtained composite copper particles have an average particle diameter of 0.3 (four), and 0.5% of the particles are contained. The above method is used to adjust: SiO 2 particles As a result, it was confirmed that there was a case where it was completely embedded in the vicinity of the surface of the mother particle, and it was embedded in the mother particle in a state where the surface of the mother particle was partially exposed. Further, there was no SiO 2 particle in the domain of the parent particle. By the above method, it is completely embedded in the vicinity of the surface of the 々 桠 桠 桠

The weight ratio of the SiO 2 particles to the SiO 2 particles in a state in which a part of the surface of the mother is exposed is the former: the latter = 6 : 4. 146549.doc -19- 201100184 [Example 2] Hundreds of 'heating 9 L of 3.6 M aqueous solution of sulfuric acid steel in a thief, adding a twist to the copper sulfate aqueous solution towel (solvent 鸠, average grain rear curve) g Thereafter, 13 〇〇ml of a 25% aqueous ammonia solution and 425 〇g of a 25% aqueous sodium hydroxide solution were successively added. Here, 450 g of hydrazine hydrate and 591 g of an aqueous ammonia solution as a pH value adjuster were continuously added to obtain a cuprous oxide mass (first reduction treatment). Next, in order to carry out the reduction reaction, stirring was further continued for 30 minutes. To the cuprous oxide slurry, an additional Si 2 sol (sol concentration 20%, average particle diameter 3 〇 nm) 25 〇 § was added in addition to the presence of the initial liquid, and then water α 肼 300 g was added. Further, the mixture was mixed for 6 minutes, and the reduction reaction was completely carried out, and the target composite copper particles were reduced and precipitated (second reduction treatment). Thereafter, composite copper particles were obtained in the same manner as in Example 。. The obtained composite copper particles have an average particle diameter of Q3 rotation, and the ruthenium contains 5% of the particles. The presence of the particles was investigated by the above method. As a result, it was confirmed that the particles were completely embedded in the vicinity of the surface of the mother particles and embedded in the mother particles in a state where the surface of the mother particles was partially exposed. Further, Si〇2 particles are not present in the central region of the mother particles. The weight ratio of the Si〇2 particles completely embedded in the vicinity of the surface of the mother particle to the si〇2 particle in a state in which a part of the surface of the mother particle is exposed is measured by the above method, and the former: the latter = 6 : 4 〇 [Implementation Example 3] First, 9 L of a 3.6 Μ copper sulfate aqueous solution was heated and maintained at 5 Torr, and a Si 〇 2 sol was added to the copper sulphate aqueous solution (sol concentration: 2% by weight, average particle diameter I46549.doc -20·201100184 20 Nm) 34 g. Thereafter, 1743 g of an aqueous solution of ruthenium oxide having a concentration of 25% of glycine acid 45 was added successively. Here, 525 g of (tetra) sugar was added to obtain a cuprous oxide bulk material (first reduction treatment). Next, in order to complete the reduction reaction, stirring was continued for 3 minutes. To the cuprous oxide slurry, a sih sol (sol concentration: 20%, average particle diameter: 2 〇 nm) i6 § is additionally added to the presence of the initial solution, and then hydrazine monohydrate (lanthanide reducing agent) 375 is added. g. Further, the mixture was stirred for 3 minutes, and the &> was completely carried out to reduce the precipitation of the target composite copper particles (second reduction treatment). The composite copper particles obtained by filtration washing (in this case, oleic acid was added as a surface treating agent) were recovered and recovered. Thereafter, 7 Gt and 5 hours of heating and drying were carried out. The composite copper particles obtained had an average particle diameter of 2 μηι, which contained 5%.5% of Si〇2 particles. When the presence of the Si 〇 2 particles was investigated by the above method, it was confirmed that the particles were completely embedded in the vicinity of the surface of the mother particles, and were partially embedded in the mother particles in a state where the surface of the mother particles was partially exposed. 〇 Also, there are no Si〇2 particles in the central region of the mother particles. The weight ratio of the SiO 2 particles completely embedded in the vicinity of the surface of the mother particles to the SiO 2 particles in a state in which a part of the surface of the mother particles was exposed was measured by the above method, and the result was as follows: the latter = 3 : 7. [Example 4] First, 9 L of a 3.6 Torr copper sulfate aqueous solution was heated and held, and 166 g of a Si 〇 2 sol (sol concentration: 2% by weight, average particle diameter: 30 nm) was added to the copper sulfate aqueous solution. Then add trisodium phosphate u. g. Thereafter, an aqueous ammonia solution (concentration: 25%) of 2,537 m was added to obtain a copper gas compound slurry. Next, 146549.doc -21 - 201100184 The copper chloride compound slurry was allowed to stand for 30 minutes to be aged. i Eight people are successively added - hydrazine hydrate (lanthanide reducing agent) 45 〇 g and ammonia solution (concentration 25%) as a pH adjuster 591 „U, while the liquid yang value is maintained at 8 边The cuprous slurry (the second reduction treatment). Next, in order to carry out the reduction reaction, the stirring is continued for 3 minutes. To the cuprous oxide slurry, an additional Si 2 sol is added in addition to the first liquid. (sol concentration 20%, average particle diameter 3 〇 nm) 334 LV, followed by adding hydrazine monohydrate (lanthanide reducing agent) 6 〇〇 g. Further stirring i8 〇,

The original reaction is completely carried out, and the target composite copper particles are reduced and precipitated (4). After the second addition of hydrazine monohydrate (lanthanide reducing agent), the pH of the system slowly decreased. At this time, &> was stabilized, and a 5 % aqueous solution of sodium hydroxide was added to adjust the p H value of the system to 8. J Composite copper particles obtained by over-cleaning (adding oleic acid as a surface treatment agent at this time) and recovering them. After that, listen and 5 hours of sputum: dry. The obtained composite copper particles have an average particle diameter of 2, wherein * 5% of SiC) 2 particles. The presence of the particles is investigated by the above method: The result is that the particles are completely embedded in the vicinity of the surface of the mother particles, and are embedded in the mother particles in a state in which the surface of the mother particles is partially exposed. Further, Si〇2 particles are not present in the central region of the mother particles. By the above method, the weight ratio of the particles in the vicinity of the surface of the S-inclusive (four) mother particle to the particle in the state in which the mother particle is partially exposed is measured, and the former is the latter = 6: 4. [Example 5] First, a 3-6 bismuth copper sulfate aqueous solution 9 [heating was maintained. [, 146549.doc -22· 201100184 This copper sulfate aqueous solution was added with 81 〇 2 sol (sol concentration 2% by weight, average particle diameter 20 nm) 16 g. Thereafter, 6 L of a 25% aqueous sodium hydroxide solution was successively added. Here, 17 〇〇 g of glucose was added to obtain a cuprous oxide slurry (the first treatment of reduction). Next, in order to complete the reduction reaction, stirring was continued for 30 minutes. To the cuprous oxide slurry, an additional Si 2 sol (sol concentration 20%, average particle diameter 20 nm) 34 g, arabic 0 gel 1 〇g, and then added sugar were added to the cuprous oxide slurry. Amino acid 160 g, hydrazine monohydrate (lanthanide reducing agent) 3000 g. Further, the mixture was stirred for 3 minutes to complete the reduction reaction, and the target composite copper particles were reduced and precipitated (second reduction treatment). The composite copper particles obtained by the cleaning are filtered and recovered. Thereafter, it was dried by heating at 70 ° C for 5 hours. The obtained composite copper particles had an average particle size of 4 μηι, which contained 5% of S 〇 2 粒子 2 particles. Investigate the existence of 2 ί子 by the above method. As a result, it was confirmed that there was a case where it was completely embedded in the vicinity of the surface of the mother particle, and it was buried in the particle in a state where a part of the surface of the mother particle was exposed. Also, there is no (10) particle in the central region of the mother particle. By the above method, the weight ratio of the Si 〇 2 particles completely embedded in the vicinity of the surface of the mother particle to the state in which the surface of the mother particle is partially exposed is measured. The former: the latter = 7 : 3. [Example 6] In Example 4, the A12〇3 sol (sol concentration: 2% by weight, average particle diameter_ instead of Si〇2 sol was used, and the a call was added in such a manner that the total amount reached 5 〇g. The 〇3 sol is not added in batches, but is added to the water ♦ solution of the copper reduced by one time. The pH after the second addition of hydrazine monohydrate (lanthanide reduction 146549.doc • 23·201100184) The value of the system was adjusted to a value of 9. The system was adjusted to have a value of 11. In addition, the surface treatment agent used stearic acid, and the composite copper particles obtained by the same procedure as in Example 4 were obtained. The average particle diameter is 2, which contains 〇.5% of the 2】3 particles. The presence of the Al2〇3 particles was investigated by the above method, and it was confirmed that there was a completely embedded surface near the surface of the mother particle. And a part of the surface of the mother particle is exposed to the mother particle. In the central region of the mother particle, there is no Α: the particle is processed. The AW3 particle completely embedded in the vicinity of the surface of the mother particle is determined by the above method. And Al2 in a state in which a part of the surface of the mother particle is exposed 3 particle weight ratio, the result: the latter = 4: 6. [Example 7] In Example 4, using Αι 2 〇 3 sol (sol concentration (four), average granules and instead of Si 〇 2 sol, in total amount Σg method added ς Ah〇3 sol. Α12〇3 sol system was added twice each time 25 〇 but after the second addition of hydrazine monohydrate (lanthanide reducing agent), the pH value was not adjusted. In addition to stearic acid, composite copper particles were obtained by the same operation as in the practice. The obtained composite steel particles had an average particle size of 2, which contained 5% of Al2〇3 particles. The above-mentioned method was used to investigate the presence of a part of the particle A. As a result, it was confirmed that there was a case where it was completely embedded in the vicinity of the surface of the mother particle, and it was embedded in the mother particle in a state where the surface of the parent particle was partially exposed. There is no particle in the center area. The AW of the particle completely embedded in the vicinity of the surface of the parent particle is measured by the above method, and the weight ratio of the particle called A in a state in which a part of the surface of the parent particle is exposed is the result of the former: the latter =6 : 4. 146549.doc •24. 20 1100184 [Example 8] In Example 6, using Tl〇2 sol (sol concentration 2〇%, average particle size 4〇(4) instead of Al2〇3 rotation, add the total amount to % g) And the surface treatment agent used lauric acid. In addition, the composite copper particles were obtained by the same operation as in & Example 6. The obtained composite copper particles had an average particle diameter of 2 _, which contained 0.5. % of the 丨〇 2 particles. The presence of the 2 particles was investigated by the above method, and it was confirmed that there was a complete 〇 & immersed in the vicinity of the surface of the mother particle, and the state in which the surface of the mother particle was partially exposed Buried in the mother particle. Further, TiO2 particles are not present in the central region of the mother particles. By the above method, the weight ratio of the Ti〇2 particles completely embedded in the vicinity of the surface of the mother particle to the Τι2 particles in a state in which a part of the surface of the mother particle was exposed was measured, and the former: the latter = 4:6. [Example 9] In Example 7, Ti〇2 sol (sol concentration: 2% by weight, average particle diameter: 5 〇 nm) was used instead of Al2〇3 sol, and the ruthenium was added in such a manner that the total amount reached 5 〇〇g. Ti〇2 sol, and 250 g was added twice in two portions. Further, the surface treatment agent uses lauric acid. Except for this, composite copper particles were obtained by the same operation as in Example 7. The composite copper particles obtained had an average particle diameter of 2 pm, and contained 5% of Τι〇2 particles. When the presence of the Ti〇2 particles was investigated by the above method, it was confirmed that the particles were completely embedded in the vicinity of the surface of the mother particles, and were embedded in the mother particles in a state in which the surface of the mother particles was partially exposed. Further, Ti〇2 particles are not present in the central region of the mother particles. The weight ratio of the Ti 2 particles completely embedded in the vicinity of the surface of the mother particle to the D 1 2 particle in a state in which a part of the surface of the mother particle is exposed is measured by the above method, 146549.doc 25-201100184 Result The former ·· The latter = 6: 4. [Evaluation 1] The composite copper particles obtained in the respective examples and the copper particles having no inorganic oxide particles and having the same particle diameter as the composite copper particles were subjected to TMA (thermomechanical analysis) to measure the heat shrinkage behavior. The results are shown in Figures 3 to 7. The measurement conditions were as follows: temperature increase rate l 〇 ° C / min, ambient gas 1 vol% hydrogen gas (flow rate 15 〇 ml / min). As is clear from the results shown in Fig. 3 to Fig. 7, the composite copper particles of the present invention have a temperature at which the onset of heat shrinkage is shifted toward the high temperature side and the heat shrinkage resistance is improved as compared with the copper single particles. Further, it is understood that the more the amount of the inorganic oxide particles, the slower the heat shrinkage progresses. [Evaluation 2] With respect to the composite copper particles obtained in Example 4, the adhesion of the inorganic oxide particles was evaluated by the following method. 25 g of composite copper particles were added to 2 mL of pure water, and ultrasonically treated for "minutes" in an ultrasonic bath of 400 W. The composite copper particles after ultrasonic treatment were separated from the liquid and recovered. , the copper can be dissolved in the liquid (14 _1 /; 1 of tannic acid water

In solution), copper is completely dissolved. Then, a hydrofluoric acid aqueous solution of U was added to the liquid to completely dissolve Si〇2. The liquid thus obtained was subjected to 1 (four) analysis as a measurement target. Based on the value contained in the complex t-copper particles before the ultrasonic treatment, the ratio of the amount of S102 remaining after the ultrasonic processing is extracted. The particles described in the embodiment (4) of Patent Document 1 and the particles described in the following paragraphs are also the same. The results of the above are shown in the following table}. 146549.doc •26· 201100184

Residual rate (%) of Si02 Example 94 Patent Document 1 (Comparative) 53 Patent Document 3 (Comparative) 45 From the results shown in Table 1, it is clear that the composite copper particles of Example 4 and Patent Document 1 and Patent Document 3 Compared to particles, the adhesion of Si〇2 is higher. [Industrial Applicability] As described in detail above, the composite copper particles of the present invention are used as a high-temperature calcined conductive paste to easily control heat shrinkability. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 (a) to (f) are views schematically showing an image of a process for producing composite copper particles of the present invention. 2(a) to (f) are images schematically showing another manufacturing process of the composite copper particles of the present invention. Fig. 3 is a graph showing the results of TMA measurement of the composite copper particles (Si〇2/Cu) obtained in Examples 1 and 2. Fig. 4 is a graph showing the results of TMA measurement of composite copper particles (si〇2/Cu) obtained in Examples 3 and 4. Fig. 5 is a graph showing the results of TMA measurement of composite copper particles (Si〇2/Cu) obtained in Example 5. Fig. 6 is a graph showing the results of TMA measurement of the composite copper particles (Al2?3/Cu) obtained in Examples 6 and 7. Fig. 7 is a graph showing the results of TMA measurement of composite copper particles (Ti〇2/Cu) obtained in Examples 8 and 9. 146549.doc -27-

Claims (1)

201100184 VII. Scope of application for patents: Particles are characterized by: Inorganic oxidized inorganic oxide particles of 〇nm are included. - Person a, said Qiu Hong Yu 匕 3. Yuan is fully embedded near the surface of the mother particle ❹ The scorpion is embedded in the masterbatch in the state of the mother's mother. • Two:::: composite copper particles in which the content of the particles is a core of the composite copper particles, wherein in the central region of the mother particles, the organic emulsion particles are substantially in a non-existent state. Shi Xi, oxygen 1 ° steel particles 'where the inorganic oxide particles are alumina, titania, yttria or yttria. 4. The composite copper particles of the broad item 1, wherein the inorganic oxide is 5. (4) is 1/10 to 1/200 of the average particle diameter of the mother particles. A method for producing a composite metal particle according to claim i, which is characterized in that: σ = directional ion species containing copper ions or containing copper, copper oxide = copper wind The aqueous liquid of the emulsion and the inorganic oxide particles is subjected to a reduction and reduction of the steel, and the 'reducing towel of copper' is added with inorganic oxide particles in addition to the presence of the first aqueous liquid spray, force or steel The positive value of the liquid in the reduction is adjusted to 7. 5 to 6. The method for producing the composite metal particles of claim 5, wherein the inorganic oxide particles are used in a state of being contained. Gelatinous 146549.doc