TW200829352A - Method for making fine silver powder and silver particles dispersion liquid - Google Patents

Abstract

A silver powder is made by using a reducing agent containing an amine free from non-saturated bond as a reducing supplement and an alcohol as a solvent, and reducing a silver compound under the presence of an organic protection agent comprising an organic compound of molecular weight of 100 to 1000 having a non-saturated bond (such as a primary amine) to produce silver particles. As a reducing supplement one or more than one of secondary amine and tertiary amine are preferably used. The silver particles thus obtained have an average diameter of 50 nm or less, for example.

Description

200829352 IX. Description of the Invention: [Technical Field of the Invention] The present invention relates to a method for producing a fine silver particle powder, which is characterized in that an ink for fine wire drawing by an inkjet method is used for forming an ink or a variety of electricity: A method for producing silver micropowder suitable for use in silver paste. Further, the present invention relates to a dispersion in which the silver fine powder is dispersed. The disk in the present invention == is composed of silver particles having a particle diameter of nm (nano). [Prior Art] When the size of the solid matter is (10) units, the specific surface area becomes tenth. Therefore, for example, the melting point is extremely lower than that of the block, and the like is a mixture of "1" particles. In the case of the towel, the activity of the nanoparticle is read = 'can be dissolved at a low temperature', so that a material having low heat resistance has long been valued as a pattern material. In particular, with the recent advancement of nanotechnology, the manufacture of simple nano-sized particles has also become easier. The method for producing the silver particle powder of the nano unit can be a gas phase method or a liquid phase method. The vapor phase method is generally a vaporization method in a gas. For example, Patent Document 1 discloses a method of evaporating silver at a low pressure of about 0.5 Torr (T〇rr) in an inert gas atmosphere such as helium. The liquid phase method, for example, Patent Document 2, discloses a method in which silver ions are reduced with an amine in an aqueous phase, and a precipitate phase of the obtained silver is shifted to an organic solvent phase (for example, a high molecular weight dispersant) to obtain a silver colloid. Further, in Patent Document 3, a method of reducing a silver halide in the presence of a thiol-based protective material using a reducing agent (alkali metal borohydride or ammonium hydride borate) in a solvent is also described. Recently, there has been a proposal for the production of practical nano-particles in response to industrial scale 319006 5 200829352 =:. For example, Patent Document 4 discloses a method of synthesizing a large amount of silver nanoparticles using silver oxide as a raw material for bamboo shoots, and further discloses that the mixed amine and silver compound raw materials are used by the dazzling! law. Non-patent literature! In the middle, it is introduced to the use of silver;: Particles ‘the technique of making silver paste. Patent Document 1: Japanese Laid-Open Patent Publication No. 2001-35255, Patent Document 2: Japanese Patent Laid-Open No. H-319538, Patent Document 3: Japanese Patent Laid-Open No. 2003-25331 No. 1, Japanese Patent No. Japanese Patent Publication No. 2〇〇6_219693, Patent Document 5: International Publication No. 4/〇12884, = Li Document 1: Zhong Xuchangmei et al., "Silver Nanoparticles in Conductive Paste Chemical Industry, Chemical Industry, In the first month of the year, the state (the subject to be solved by the invention) The desirable use of silver fine powder is the fine wire drawing used in the inkjet method. • I7 ink or silver paste. The inkjet method can form fine lines and wires. Moreover, it is possible to connect the wiring body (no etching is required), so that it is not expensive and does not require a mask, a liquid, etc. However, since the inkjet method is a small point weight® The method of forming a line or a surface, so it is efficient to use a wire that is suitable for use, and a dispersion having a high silver concentration (ink) is required. On the other hand, 'the silver paste is also desired to be a high concentration of silver. Disperse 1 for the above purpose, also to modulate A dispersion having a high silver concentration is preferred. However, in the prior art, the interface activator 319006 6 200829352 which is present in the silver dispersion becomes a cause of hindering the dispersion when the concentration of silver is increased. In other words, in order to increase the concentration of silver in the silver dispersion, The particles are agglomerated and it is difficult to form a uniform dispersion. If this problem can be solved, the application feasibility of the silver micropowder is expected to leap. The present invention is in view of the above-mentioned situation, and the heart is more capable of improving the dispersion of particles in the liquid medium. The production of silver micropowder is highly productive, and the manufacturing technology of silver micropowder suitable for industrial production is provided. [Invention] To achieve the above object, the present invention provides a method for producing silver micropowder, which is a solvent alcohol. The presence of an organic auxiliary material composed of an organic compound (for example, a phantom amine) having an unsaturated binding molecular weight of 100 to 1 _ as a reducing agent. The method of producing a silver powder is carried out by reducing and treating the silver compound and causing the silk to be separated. In the present invention, an alcohol means one or more of a monohydric alcohol and a polyterpene alcohol (polyol). The reducing aid is preferably an amine having a quaternary amine or higher, i.e., a quaternary amine or a ternary amine. The average particle diameter of the silver particles is, for example, 50 nm or less in the following Dtem. The present invention provides a method for producing a silver fine powder comprising the following steps, that is, a step of performing the above-described reduction treatment, and separating a liquid containing precipitated silver particles (4) to separate 'silver coated with an organic compound constituting the silk-shielding material When the particles are in the form of S], the above-mentioned silver particles coated with the organic compound are dispersed in a non-polar or polar liquid solvent, or the dispersion is subjected to centrifugal separation treatment, and the dispersion is dispersed. The silver particles are formed by the step of clearing the liquid. The term "non-polar or low polarity" as used herein refers to 319006 7 200829352 which means that the permittivity at 25 ° C is 15 or less. The amount of silver per lkg of the alcohol of the above-mentioned reduction treatment solvent may be 〇 2 ～ to 20 mol. Further, it can be carried out at a ratio of the organic protective material/silver molar ratio; at 〇· 05 to 20, and the reduction aid/silver molar ratio can be reduced at 0.1 to 20°. Further, the present invention can provide a dispersion of silver particles having the following properties. In the dispersion, the average particle diameter Dtem is 5 〇, and the silver particle powder is dispersed in a low-polarity liquid organic solvent to form a dispersion of silver particles. A silver particle dispersion having a concentration of silver of 5 to 90% by mass, a viscosity of 50 mPa·s or less, and a surface tension of 8 〇mN/m or less. The dispersion has excellent dispersibility, for example, a degree of dispersion of a membrane filter having an average particle diameter of silver particles in liquid + 2 〇 nm pore size. Further, Benben & is used in a first-grade amine, in the presence of either or both of a secondary amine or a tertiary amine, at 8 Torr to 2 Torr. In the 〇 temperature range, the method of manufacturing the silver micropowder is reduced by the Xinyi silver salt. Since the silver fine powder obtained by the present invention is a nanoparticle, it exhibits extremely excellent dispersibility in a liquid solvent of low polarity. Therefore, the preparation of a high concentration of the silver dispersion can also prevent the aggregation and precipitation of the particles, so that it is suitable for the ink or silver paste for fine wiring. Further, since the production method of the present invention is excellent in the reduction ratio or dispersion efficiency of silver particles and is suitable for mass production, it contributes to the industrial spread of silver fine powder having excellent dispersibility. [Embodiment] (Best form for carrying out the invention) 319006 8 200829352 2 by "reduction step", "solid-liquid separation" via "gradation + step two:: political silver powder in liquid solvent. After dispersing the finely dispersed silver particles in a liquid state, for example, a dispersion of silver (for example, ink, etc.) is dispersed in a high concentration in an adjustment step. 夂: If necessary, it may be inserted and washed. Steps, etc., "^ Dissolve the silver compound in a reducing solvent, to reduce the precipitation, and to precipitate. Warm the solvent, preferably to make it the reflux state, the alcohol of the winter agent can reduce the silver of the silver The silver of the metal is precipitated. At this time, when the reduction reaction is carried out in the presence of the organic protective material, the silver fine particles having the uniform spherical shape covered by the compound constituting the protective material can be synthesized. The reducing agent is further used in addition to the alcohol of the solvent, and the reducing agent is composed of a substance having a stronger reducing power than the alcohol: by using a reducing aid to reduce the silver which cannot be reduced by the alcohol, the silver can be raised _ Shopping According to the research review by the present inventors, although the use of a plurality of organic protective materials is advantageous for improving the dispersion efficiency (refer to the following), the use amount of the organic protective material increases, and the reduction rate tends to decrease. Even when a reducing aid is used, the amount of the organic protective material used is increased by a large amount, and a high reduction ratio can be obtained. As a result, when silver fine powder composed of silver particles having excellent dispersibility is produced, the yield of silver can be greatly improved. The order of the reduction treatment may be, for example, as follows: First, an organic protective material is mixed with an alcohol, and a silver compound is added to the solution to dissolve it. Thereafter, the reduction reaction is started by heating in a vessel equipped with a reflux apparatus. When the reaction is carried out under reflux conditions at 319006 9 200829352, the efficiency is better. Initially, only the reduction force of the alcohol is used to precipitate the silver particles. When the reduction reaction is carried out by alcohol, some or all of the reduction aids may be added. 'But when the reduction reaction of the alcohol is almost finished, the addition of a reducing aid' restores the remaining silver that has not been reduced to Preferably, the original reaction temperature is > (4) 匕 dry solidification is better. When the reaction overshoot is too low, the reduction of alcohol can not be exerted, not only the reaction is difficult to progress, but also the risk of poor migration occurs. When the reaction temperature is too high, the reduction is excessive, the coarsening of the particles, or the dispersion of the particle diameter (4) is dangerous. For the use of the ink, the silver fine particles having an average particle diameter Dtem (see below) of 2 〇 nm or less are used. Ideally, the reaction temperature is preferably from 50 to 15 (the range of TC is preferred, wherein the range of 60 to! hunger is more preferable. In the case of rc range l', it is easier to obtain excellent results. 'Depending on the situation, the reduction can be divided into multiple stages of implementation. That is, when the reduction is urgently ordered, the growth of the particles will be too significant. In order to effectively control the particle size, the reduction reaction is first carried out at a low temperature, then turned to a high temperature, or slowly increased. The temperature is lowered again and again. At this time, when the temperature difference is too large, there is a concern that the particle size distribution fluctuates significantly, so the difference between the lowest temperature and the highest temperature is ideal within 20 degrees. It is especially tightly controlled within 15〇c, especially inside the muscle. Alcohols The solvent used as the main reducing agent in the present invention is an alcohol (the monohydric alcohol = the lower one), and the synthetic impurities can be mixed into the low-fat, and the efficiency is better. Therefore, the alcohol point of the alcohol is 319006 10 200829352 The lower one is better than the best one of which is 30 (the following is suitable for rc, 2 is preferred. The following is preferred, preferably 150 C or less. Specifically, when using monohydric alcohol, the boiling point is in the range of up to 200 °C. When the polyol is used, the boiling point is in the range of 15 Å to 3 Torr. The alcohol is as long as possible in terms of the reduction of the carbon chain. For example, isobutanol or butanol can be used. 2_propanol, p-hexanol, ^ ° silver compound. Supply silver ion source of silver, can be used in alcoholic solvents in silver chloride, silver sulphate, silver oxide, silver carbonate, etc. Industrial Appropriation 1 is obtained and compared with (4) light silver is more suitable. The use of silver compounds in the valley "sterols per 叱" is set at about 2. 2 to 2 ° molars of silver, 聋: within the above-mentioned consumption, relative to Organic protective materials or reductions are preferred, and it is preferred to use a suitable amount of silver in the appropriate range. In terms of the molar concentration of silver, 'the silver concentration is about 0. 〇5 to • Moule/L. μμμμμ. 'I want to: =! Reaction, coexistence of organic protective materials in the solvent for retrial The organic compound constituting the organic protective material is a type of the surface of the back cover silver fine particles, and is used as a material of the latter, although: =: function. It is suitable as an organic protective material. According to the study of the present inventors /Unsaturated knots from the dissolution of silver salt - high, " ίφ like this original step, if you Tian Qiaozhi / 谷剂令 'directly precipitated silver method, when the material, not: Γ When the organic compound is used as an organic protective material with an organic compound which is unsaturatedly combined, it can be known that it can synthesize two 319006 11 200829352 ^ machine compound to keep the silver fine powder. The original 0 is still unknown, the table: from the compound The effect of the unsaturated bond, the precipitated compound 'this organic compound makes silver reduction in a certain = grain growth is suppressed, in order to form fine silver particles. Another;, fruit 'solvent dispersibility. Existence As far as the organic research is concerned, as far as the research is concerned, the number of unsaturated bonds at this time must be adjusted to cover the surface of the silver particles by having a branch compound - at least one unsaturated bond in the molecule is sufficient to ensure the number of unsaturated bonds. π' sighs the carbon number in the sputum, so the organic compound with different number of unsaturated bonds can be added according to the demand. The material = protective material can be used with the molecular weight of (10) to mo, the molecular weight is 1 〇〇 to The torn organic compound is preferred. When the fraction is less than 100, the aggregation inhibition effect of the particles is low. When the molecular weight exceeds the enthalpy, although the aggregation inhibition force is large, the stagnation point is high, so the 匕 is used. When the coated silver particles are used as an ink or a paste, the protective material is less likely to cause volatilization when the ink is applied by the ink or paste moxibustion. Because the silver film will contain more impurities. Further, particularly in the ink, the amount of the protective material on the surface of the particles is increased, which is disadvantageous for the ink having a high silver concentration.

The amount of organic protective material coexisting in the solvent, the organic compound of the protective material and the molar ratio of silver in the silver compound, ie, the mechanical protection 4 material / silver molar ratio can be Q• The farewell, which is U 319006 12 200829352 to |., 5 is ^ soil, with 2. 〇 to 1 〇 is better. When the use of the organic protective material is too small, the organic compound covering the surface of the silver particle (the amount of the protective material is insufficient) cannot sufficiently ensure the dispersibility in the solution. Conversely, when it is too much, the printing, the middle, and the relative The ratio is lowered, and the organic protective material is increased at the same time, which is not good from the viewpoint of industrial production. Specifically, for example, when oleylamine is used as the organic protective material, setting the organic proof ratio in the range of 5±3 is effective. An example of an organic compound constituting an organic protective material, such as acrylic acid, oleic acid, linoleic acid, arachidonic acid, nervonic acid, tungstic acid, isooleic acid, linolenic acid, etc. For example, triallylamine, oleylamine, etc. Among them, a grade 1 amine is preferred, and in particular, the adhesion of oleylamine to the surface of the silver particle is not too strong, so the protective material on the surface of the particle is changed from oleylamine. It is relatively easy to operate the organic compound with a lower amount of splitting, and it is extremely advantageous to obtain a silver fine powder having a low sintering temperature. These are organic protective materials, which can be used alone or in combination of two or more. The chemical reduction aid of the house 1 is a silver compound which cannot be reduced only by the reducing power of the alcohol, and the reducing agent for reduction is extremely important in order to increase the reduction rate of silver. In the present invention, an amine is used. The molecular weight is preferably in the range of 50 to 1000. The amines used in the reduction aids may be various amines of the above-mentioned amines or secondary amines. However, when the first-grade amines are used, unlike the organic protective materials, they are not selected. A compound which is unsaturatedly bonded. Among the amines, it is preferred to use a secondary amine or a tertiary amine having a high reducing power. Even if a primary amine is used, the reduction ratio can be improved, 319006 13 200829352 However, when the amount of the organic protective material is used, The dispersing efficiency is more effective in the second or second grade amines. The reduction aids make the Xuan, Li make the Mobibi dry between the silver in the amine and the silver compound which is the original auxiliary agent, that is, The original additive / silver molar ratio 妒, Shi Rong n 卞Α υ · 1 to 2 〇 is ideal. Although;, \ can be added more can also be, but within the above range, for the effect of reduction and After the dispersion effect, "" ^ ^ ^ month and He Gu Yi Which is obtained on the two balance. Tour molar ratio of the silver to the original promoter # 10

• Better to 10. An example of an amine having AU = pro-auxiliary such as N,N-diethylethanol-methyl-aminedamine ethyl)ethanolamine, methyldiethanolamine, -butylethanolamine, N-methylethanolamine, diiso) Propylamine, diethylene trioxide:: ethanolamine, bis(2-cyanoethyl)amine, iminobis(propylamine), N-n-butylamine, diphenylamine, bis-2-ethylhexylamine, two Octamine, trimethylamine, dimethylethylamine, N- succinyl-methyl #, y xiao m diethylamine, tetramethylethylenediamine, -ethylethanolamine, methyldiethanolamine, triacrylamide, N-methyl_3 3, a sub-private bis (propylamine), triethanolamine, a makeup 0 [monobutylamine) propylamine, N-nitrous acid: an amine, triphenylamine, tri-n-octylamine, etc. . Among them, it is industrially more suitable! It is suitable to obtain diethanolamine or triethanolamine which has a strong reducing power in the amine. The aminated compound as a auxiliary additive may be used alone or in combination of two or more.

An alternative method for making silver micropowders using the 0 W five-class process is in the first-grade amine, in which the silver salt is coexisted with the mono- or both-grade amines, or at (9). The temperature reduction of C can be made by reduction treatment under dry conditions. In this case, instead of using the above alcohol, 丨 319006 14 200829352 amine is used as a reaction solvent and a reducing agent for silver ions, so the types of the amine, the second amine and the tertiary amine used may be as described above. 4 According to the method of the present invention, silver fine powder having an average particle diameter Dtem of 50 nm or less can be obtained. The crystal grain size Dx is 50 nm or less, and the degree of single crystallinity (]) TEM / i) x) is preferably 2.0 or less. Solid-liquid separation step In the slurry after the completion of the reduction reaction, silver particles coated with an organic compound (protective material) constituting the organic protective material & The slurry was subjected to a solidification liquid knife to remove the silver fine powder of the solid matter. The solid-liquid separation enthalpy operation can be repeated several times in combination with washing. For example, it can be repeated in the order of [1] to [4] below. [1] The slurry after the reaction of the original reaction is subjected to solid-liquid separation by a decantation method or a centrifugal separator to remove the supernatant liquid. The sterol is added to the solid matter obtained by the solid-liquid separation described above (that is, the resultant is subjected to ultrasonic dispersion treatment to wash away impurities attached to the surface of the product. In the following examples, the amount of silver fine powder produced can be obtained in the following order) The measured mass value is the mass of the paddle liquid after the reaction before returning to [1], as 319006 200829352, (·) taking a sample (for example, 40 mL) from the water liquid fraction, and measuring the mass as the B mass value. ' • (111) The 40 ml of the slurry obtained is returned to the solids according to the above [2] to [4] and placed in the known 00. After knowing that I was in the valley of the 1st, I was vacuumed at 2〇〇〇c and dried for 12 days. The mass of the dried product obtained was measured as a mass value of c. The amount D of silver fine powder (including the amount of the protective material present on the surface of the particle) produced by (1 V) can be calculated by the following formula. ', ^ D = Cx (A / B) Lu reduction rate & The "reduction rate" used in the specification of the success rate of the reduction reaction in the present specification can be determined from the silver mass e of the silver compound before the start of the reaction, and Find the ratio of D / and calculate. That is, the 'reduction rate' can be obtained by the following formula. ^ Return rate (%) = D / Exl 〇〇 The value of the reduction rate is the rate of silver when the surface frequency is the reaction product. If it is completely reduced, the amount of silver fine powder includes its surface and has a machine The value of the compound (protective material) may also be higher than 100% and the fading rate. To date, according to the inventors' knowledge, the reduction rate of the silver-extended powder according to the method of the present invention is known to be in the range of about 85 to 120%. [1] The solid matter obtained after the above solid-liquid separation step is added to the following liquid solvent.卞 The organic compound is a non-polar or low-polarity liquid solvent, and is a liquid solvent having a permittivity of 15 or less at m:. Example 319006 16 200829352 Xinxuan, Zhengyiyuan, Zhengyishhu, n-tetradecanedioxane, hexane, heptane, etc., aliphatic hydrocarbons, :::: ten or more species can be extracted from the field, square In the case of smokeless ones, the solvent can maintain the above low polarity range. • Other dispersing aids such as amines can also be added. in. [2] Secondly, the ultrasonic dispersion is applied to disperse the solid matter in the liquid solvent. The unevenness of the silver particles obtained by the step of dispersing the liquid I, and the three people are right and the knife is released/night. Silver particles with excellent dispersibility and silver particles with poor dispersion. Therefore, it is advantageous to use a fine dispersion of the silver particles from the silver particles to form a dispersion liquid. The classification step is a step of obtaining the above dispersion. ... The grading operation can use the size or purpose of the centrifuge. (4) The conditions vary with the ancient times, and the level of the upper knives is different. For example, the dispersion obtained by holt is dropped by the centrifuge. It is separated from the liquid and the sediment. According to this, the Norwegian government has silver particles that are extremely well dispersed. Therefore, the recovery of the supernatant can be obtained by extremely good dispersibility < 彡 Disperse 岐 Good 料 (4) narration powder. The ratio of the amount of silver and the mass of the sediment contained in the liquid is called [Knife-Policy Efficiency], and its definition is as follows: 卞文([The quality of the silver granules produced by the solid-liquid separation step is teasing D)] - [mass of substance attached to the wall surface of the container after centrifugation]) / [mass of silver fine powder produced by the solid-liquid separation step (D above)] xl (; 319006 17 200829352 Here, the above is attached to the wall of the container The mass of the substance can be measured by vacuum drying at 20 (TC) for 6 hours. The higher the dispersion, the higher the dispersibility of the particles as the dispersed colloid. The value of the beans is 60. % or more is preferable, and it is preferable that it is 7 % by mass or more, and preferably 8 % by mass or more. The yield is defined as "yield" in the dispersion obtained after the final classification step as an index indicating how much silver is recovered. The definition of the yield is as follows: No. Yield [reduction rate of the enemy (the "dispersion effect::" means that the silver compound in the silver compound used in the raw material is very good. The sound of high yield. Drying machine =:::: Silver:, _ liquid), formed by vacuum drying = two = concentrate in the above liquid solvent mass% 乂 太八私度 / knife discharge liquid. Silver concentration may be up to 90. The silver concentration in the knife discharge liquid can be analyzed by ICP analysis of the dispersion liquid It is difficult to scale up the scale of the two-meter particle colloidal liquid. The average particle size of #1 can be obtained according to the following method. The average particle size of the silver particles is transmitted electron microscope 319006 18 200829352 ( The average particle diameter obtained, that is, the average particle diameter value of the particles of 300 particles without weight 4 measured by a transmission electron microscope at a magnification of _, _ times. In the invention, it is possible to obtain silver fine powder of 50 nm or less. The use of fine wiring is more suitable for "2" (10) and =::15 nm or less, and it is most suitable for those below i〇nm: The electron microscope (TEM) is a JEM-201 type which uses the product of Sakamoto Electronics. The physical properties of the dispersion obtained by the present invention are as follows. Φ viscosity, according to the present invention, a low viscosity silver nano ink can be obtained. In the East, the system is based on杂 π 辅 辅 η 司 0 0 0 550 550 550 550 550 550 RE RE RE RE RE RE RE RE RE RE RE RE RE RE RE RE RE RE RE RE RE RE RE RE RE RE RE RE RE RE RE RE RE RE RE RE RE RE 8 8 At this time, it is suitable for:: preferably below 4GmPa · s. For example, adjusting at q. i to * s

Dry circumference, as long as the adjustment in 〇 1 ^, S adjust the silver nanometer a ± within this range. Using the viscosity p,;, p W day, it is not easy to occur nozzle resistance 1 mp a ' ΓΓ, Γ ^ ° ^ ^ ^ ^ ^ ^ ^ ^ II i Yield tension The silver particle dispersion of the present invention is in hunger The surface is 80 mN/ra or less. Therefore, it is suitable for the material. F-speech ^7 + v is a dispersion of the surface tension of the wiring in the Hemo method, which is unstable in shape, so the amount of spit is niscus), and the time is from the p or the spit. The regulation is difficult, and the wettability of the droplets of the substrate is poor, and the junction flatness is poor. 319006 19 200829352. However, since the surface dispersion of the silver particle dispersion of the present invention is below, the above problem does not occur, and a wiring having good quality can be obtained. The surface tension was measured using a CBvp_z type instrument of the product of Concord Interface Science Co., Ltd. at a constant temperature of 25 °C. Membrane of membrane filtration The silver particle dispersion of the present invention is passed through a membrane crucible having an average particle diameter (D) of the silver particle powder and a pore diameter of 2 〇 nm. Since it is only passed through a pore diameter larger than the average particle diameter of the silver particles (D is 20 nm, the silver particles in the dispersion are not aggregated, and the particles can flow in the liquid, that is, almost completely monodispersed. However, this also means that the dispersion of the silver particles of the present invention is extremely suitable. The material for forming the wiring by the Hemo method. When the particles have agglomerated portions, not only the clogging of the nozzle but also the filling of the formed wiring is likely to occur. Sexual change is a cause of high resistance or open circuit when holes are formed during calcination. However, the above-mentioned problem can be avoided in the dispersion of the present invention. Membrane 过 过 试验 $ ' ' ' What What What What What What What What What What 〇pplus 25 injection filter _ state (20nm pore control) as the smallest pore size device. Acid value The pH value (hydrogen ion concentration) of the silver particle dispersion of the present invention is 6.5 or more. Therefore, as wiring When forming a material, there is a feature that the copper foil on the circuit board is not rotted, and it is difficult to move between the wirings. The p Η value of the dispersion is an acid tester d _ 5 5 τ using a product of Horiba Co., Ltd. ^ type, low The electric water-nonaqueous solvent is measured by the ρΗ electrode 6377_1〇d. When the pH value of the dispersion measured by this method is less than 6.5, the copper on the circuit board is caused by the acid component, and the movement between the wirings is likely to occur. And reduce the reliability of the circuit 319006 20 200829352. [Embodiment] - Comparative Example 1. Select isobutanol (Wako Pure Chemical Co., Ltd., special grade reagent) as an alcohol solvent with reducing power, mixed as organic protection The material is oleylamine (product of Wako Pure Chemical Co., Ltd., special grade test). Silver nitrate crystal (manufactured by Kanto Chemical Co., Ltd., special grade test) is added to the mixture as a silver compound, and the silver nitrate is dissolved by a magnetic stirrer/stirring. The mass of each substance used is 0.159 g of Mn silver nitrate, 96.24 of isobutanol, and 165.462 of oleylamine. The organic protective material/silver molar ratio is equivalent to 5.0. The liquid is transferred to a reflux device. In a 300 ml container, placed in an oil bath, one side of the container was introduced with nitrogen gas of an inert gas at a flow rate of 400 ml/min, and heated under stirring with a magnetic stirrer of 1000 rpm, and the temperature rising rate was 2 ° C / min, liter. The liquid temperature is 100 ° C. The reaction is carried out at 100 ° C under reflux, and the reaction is carried out at 300 ° C. The reaction is carried out without adding a reducing aid. After the reflux for 30 minutes, the heating is stopped and the reaction is terminated. The subsequent slurry is subjected to the above-mentioned "solid-liquid separation step", "dispersion step", and "staged step" to obtain a silver fine powder having high dispersibility. In the solid-liquid separation step, in the step [1], Hitachi is used. The centrifuge model CF7D2 of the machine company was centrifuged at 3000 rpm for 30 minutes. The kerosene was used as a liquid solvent in the dispersion step. The fractionation step was carried out by centrifugation at 300 rpm for 30 minutes using the above centrifuge, and the supernatant liquid on which the silver particles were dispersed was recovered. The reduction rate, dispersion efficiency and yield were obtained by the above method. The results are shown in Table 1 (hereinafter, Comparative Examples 2 and 3 are also the same). 21 319006 200829352 _Comparative Example: In comparison with Example i, except for changing the amount of oleylamine used in organic protective materials. • The organic protective material/silver molar ratio is 3

In the middle, after the reflux of the minute, in addition to the addition of n 酉 ^ (Wako Pure Chemical Co., Ltd., special grade drug) 12. Called the second-grade amine as a general additive 'maintain the above reflux state for 1 hour and react 'When the heating was stopped, the rest were prepared under the same conditions as in Comparative Example 1; the silver fine powder of Example 1 was known. At this time, the reduction aid/silver molar ratio was equivalent to ° u°, and the reduction ratio, dispersion efficiency, and yield were determined according to the above method. It is not in Table 2 (hereinafter, Examples 2 and 3 are also the same). i Examples 2 and 3 In Example 1, except for the amount of oleylamine used in the organic protective material, the organic protective material/silver molar ratio was changed to 40 (implement 2) and 2.0 (example 3), respectively. The rest were obtained in accordance with Example 1 to obtain silver fine powder.仟 319006 22 200829352 Table 2

Organic protective material / silver molar ratio reduction rate (%) 98. 4% i9. 2% ~ 9G. 8% dispersion efficiency (%) 95^7% 'uTo% 94. 1% ^0% Example 1 ΓΤ- ρ from amine oleylamine 3 oleylamine reduction aid silver molar ratio

::W to 3 and Comparative Examples i to 3, the obtained organic protective material/silver 4 ears (four) and the dispersion efficiency _ expressed in the relationship between the molar ratio of the silver and the reduction ratio are expressed in the second == comparison example. From the second: the second grade amine of the hunting ice plus the original additive can improve the dispersion effect = two additions: when the reduction aid, _ Mo Er is dry to the south and has a tendency to reduce the reduction, but the auxiliary, organic protection Material/silver molar ratio variation Γ also = material/silver molar ratio two: two 'dispersion efficiency with the added force of organic protection' and in the high organic protective material / silver J 7 (four) original step, Achieving yield (reduction rate and dispersion efficiency: improvement in the field. This industrially produces a large amount of disperse silver pebbles: for: productivity improvement 'production cost reduction Wei,: extremely significant meaning.

Example 4 s G DiB::! In Examples 1 to 3, except that the reducing aid was changed to 3 amines, respectively, the other conditions were the same according to the conditions of Examples 1 to 3 to obtain 319006 23 200829352 silver fine powder. The results show that the above method is used to obtain the reduction rate, dispersion efficiency and yield table.

For the examples 4 to 6 and the molar ratio and dispersion efficiency of the second & 1 Λ, the i organic protective material/silver material/wearing stem and ^ is expressed in the 3W, the ratio of silver to the organic protective material and The _ of the reduction rate is shown in the figure of the ruth, and the △ 络 夺 ' When the third-order amine is added as a reduction aid in Figures 3 and 4, (a) the change in the molar ratio of silver is expected to be expected. Only after the original rate can be achieved, high yield can be achieved. In Examples I to 3, except for the reduction aid, ethanolamine, the other amines were changed to single powders according to the amines. According to the above method, (4) the original rate is obtained, and the condition of obtaining the silver micro is shown in Table 4. Knife political attack rate and yield. Results 319006 24 200829352 Table 4

In the reaction solvent-reducing agent, 185. 33 ml of oleylamine (manufactured by Wako Pure Chemical Industries, Ltd., Mw=267) was added as an organic protective material, and silver nitrate crystals (product of Kanto Chemical Co., Ltd.) 19. 218 g was used as a silver compound. The silver nitrate was dissolved by stirring with a magnetic stirrer. The solution was transferred to a reaction vessel equipped with a reflux device, placed on an oil bath, and a nitrogen gas of an inert gas was introduced into the vessel at a flow rate of 400 ml/min, and heated by a magnetic stirrer at a rotational speed of 100 rpm at a rotational speed of 100 rpm. . The temperature was raised to 100 ° C at a temperature increase rate of 2 Χ: /πάη. After refluxing at 100 ° C for 5 hours, a second-grade amine diethanolamine (and: Wako Pure Chemical Industries, Mw = 105·64) 12.1 g (for silver molar ratio of 1.0) was added as Reduction aid. Then, the reaction was terminated by holding for 1 hour. The slurry for terminating the reaction was subjected to the "solid-liquid separation step", the "dispersion step", and the "staged step" in the same manner as in Comparative Example 1, to obtain a silver fine powder having high dispersibility. As a result, the reduction rate was 1%, the dispersion efficiency was 89.8%, and the yield was 89.8%. Example 11 In place of the diethanolamine instead of the second-grade amine, the tertiary amine triethanolamine was used (and For the product of Wako Pure Chemical Industries Co., Ltd., Mw=149· 2)17·05g (the ratio of silver to silver is 1·0) was repeated as Example 1 except for the reduction aid. The liquid slurry for terminating the reaction was subjected to a "solid-liquid separation step", a "dispersion step", and a "staged step" in the same manner as in Comparative Example, to obtain a fine silver-containing fine powder. As a result, the reduction ratio was 97. 4%, the dispersion efficiency was 94.7%, and the yield was 92.2%. Comparative Example 4 Example 10 was repeated except that no reducing aid was added. However, since no reducing aid was added, the reaction was terminated by refluxing at loot: for 5 hours. The liquid slurry after the termination of the reaction was subjected to the same procedure as in Comparative Example 1, and the solid-liquid separation step, the "dispersion step", and the "staged step" were carried out to obtain a silver fine powder having a dispersive property. As a result, the reduction ratio was 70·1%, and the dispersion efficiency was 319 319006 26 200829352 The yield was 58·5%. Compared with Examples 10 and u, the reduction rate was low and the dispersion efficiency was also slightly lower, so that the yield was also low. 4 [Simple description of the drawings] ..* 1 is a graph showing the relationship between the organic material f/silver molar ratio dispersion efficiency for Examples 1 to 3 and Comparative Examples i to 3. Fig. ^ ^ Table of inconsistency' △ indicates a comparative example. Fig. 2 is a graph showing the relationship between the organic protective material/silver molar ratio and the reduction ratio for Examples i to 3 and Comparative Examples i to 3. In the figure, the examples are shown in the accompanying drawings, and Δ indicates a comparative example. Fig. 3 is a graph showing the relationship between the organic protective material/silver molar ratio and the dispersion efficiency for Examples 4 to 6 and Comparative Examples 1 to 3. In the figure, Lu represents an example, and Δ represents a comparative example. Fig. 4 is a graph showing the relationship between the organic protective material/silver molar ratio and the reduction ratio for Examples 4 to 6 and Comparative Examples 1 to 3. In the figure, Lu shows an example, and Δ shows a comparative example.

Figure 5 is a graph showing the relationship between Example 7 and the molar ratio and the dispersion efficiency. Fig. 6 is a graph showing the relationship between the molar ratio and the reduction ratio of Example 7 and the organic protective material/silver, indicating its organic protective material/ Silver 27 31%〇6

Claims (1)

200829352 X. Patent application scope: The prescription is as follows: in the alcohol, the alcohol ^35 is used as the ^ and the reduction consists of the amine without the unsaturated combination. The auxiliary agent is used as the remote agent. In the presence of an organic protective material composed of an organic compound having an unsaturatedly bonded molecular weight of A lnn to 1 000, the silver compound is depreciated to precipitate silver particles to produce silver fine powder. • A method for producing a silver micropowder characterized in that it is composed of an alcohol as a solvent and an amine having a higher amine or higher; ο, a reducing agent composed of a core makeup is used as a chemical agent, and the silver particles are precipitated in the silver plating material of the organic protective material composed of an organic compound having a molecular weight of 100 and a combined organic compound. A method for producing silver fine powder. The method of manufacturing: the method comprises the steps of: (1) processing the patent application scope (1) or the (2) treatment, and separating the poly-liquid of the sub-component into solid-liquid separation, and the silver particles coated by the organic protective two-t-t material In the step of recovering the material, the step of dispersing the above-mentioned organic particles is carried out in a non-polar or polar liquid solvent. A method for producing silver micropowder, which has the following steps: 4 - The step of reduction treatment of item 1 or item 2, which comprises: the liquid of the extract is solid-liquid separated, and the organic protection is constituted by == a step of recovering the coated silver particles in a solid form, a step of dispersing the silver particles coated with the organic compound in a liquid solvent having a small or low polarity, and applying the separation liquid to the dispersion liquid . After the knife is used, the recycling points 319006 28 200829352 5 · If the application of the patent scope of the first method, the dragon passed! In the treatment of silver micropowder* in the protection of materials, the use of a grade 1 amine as the above organic: 6'C: the silver micropowder of any of items 1 to 5 of the range The 'reduction treatment' in P is carried out by using alcohol = 0.2 to 2 moles per alcohol as a solvent. ...manufacturing, ^利1&1^ Item 1 to Item 6 of the silver fine powder system wherein the 'reduction treatment is carried out under conditions of organic protective material/silver molar ratio of 0.05 to 20 . 8 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 Under the conditions. 9. The method for chemically pulverizing the invention according to any one of Items 1 to 8 wherein the average particle diameter of the silver particles is the following. A silver particle dispersion liquid is a silver particle knife "night" in which a sub-powder having an average particle diameter DtEM of 50 nm or less is dispersed in a liquid organic solvent having a low polarity, and is characterized by having the following silver particle dispersion as a Newtonian fluid property. Liquid: The acid-base (pH) value is 6.5 or more, the silver concentration in the dispersion is 5 to 90% by mass, the viscosity is 50 mPa·s or less, and the surface tension is 80 mN/m or less. 11. If you apply for a patent scope! The silver particle dispersion of the present invention is a dispersion of a membrane filter 29 319006 200829352 having a pore diameter of +20 nm having an average particle diameter of silver particles in the liquid. 12. A method for producing a silver micropowder characterized by a silver salt in a first-grade amine, in the presence of one or both of a secondary amine or a tertiary amine, and at 80 to 200 ° C The reduction treatment is carried out within the temperature range. 30 319006