TW200536636A - Highly crystalline silver powder and method for production thereof - Google Patents

Abstract

A method for producing a highly crystalline silver powder is characterized in that a first aqueous solution containing silver nitrate, a dispersing agent and nitric acid is admixed with a second aqueous solution containing ascorbic acid, wherein the dispersing agent is preferably poly(vinyl pyrrolidone) or gelatin. A highly crystalline silver powder produced by the above method preferably has a D90/D10 of 2.1 to 5.0, a diameter of a crystallite greater tahn 300 AA, an average particle diameter D50 of 0.5 to 10 mum, and exhibits thermal shrinkage in the longitudinal direction at 700 DEG C of within &plusmn 3 %. The above highly crystalline silver powder is composed of fine particles with good dispersibility, broad particle size distribution, and large crystallites.

Description

200536636 IX. Description of the invention: [Technical field to which the invention belongs] = Ming is related to a highly crystalline silver powder and its manufacturing method: Xiong Mingzhi is related to a highly crystalline silver admiral such as wafer element, electricity :: method It is enough to form high-density and high-quality electric pastes, especially for fine lines: the guide of the sexist is enough to open the point and the ancient ^, 'road or, look for layers and smooth The coating film can be multi-spooned into a conductive paste with a density of 及 and a high ancient quality, and it is also guilty of a conductive paste :: so it is better; because it is a fine particle, has good dispersibility, and does not cause particle size distribution Too steep and relatively wide, with large crystallites, ^ fxm ^, used as a raw material for conductive paste # 银 私 dispersibility of poor agent and silver powder is quite excellent, and can make the filling in the stomach M more fine It can be made from the light-conducting circuit and the circuit # which have excellent shrinkability and the same: the obtained silver thick film is made of heat-resistant [prior art] ^ lower specific resistance (resistivity). In the past, it has been used as an electrode for forming electronic components or a method with good conductivity. A method for dispersing silver paste in a paste is used to print this conductive paste on a substrate. It can be cured by curing and hardening to form a silver thick film to make a circuit. However, in recent years, electronic devices have been required to be highly functional and compact and high-density. Therefore, the primary beta, Jinyi electronic devices Powder, when made into a conductive paste: :::: The silver of the material of the second paste sword is quite bipartite in terms of fillability or dispersibility = Weijiao 4 The so-called dispersibility system, as long as it is not previously used in the present invention ° Brother Ming 'refers to silver powder

2213-6834-PF 5 '200536636 degrees. The example of "knife release" means the difficulty of agglomeration between the original particles of silver powder: ratio two, the so-called good dispersibility state refers to the state that the original particles are agglomerated, and the shoulders or elements are not agglomerated; the so-called poor dispersibility state ': A state in which the ratio of agglomeration is large or completely agglomerated. The substrate printed with the above-mentioned conductive paste on the substrate tr is usually used for a part with a large heat radiation, such as a ceramic II device. However, in this ceramic-based: conductive brush, the thermal shrinkage of

The thermal shrinkage of the silver thick film produced by one of them is generally inconspicuous. Therefore, there may be separation or peeling between the ceramic substrate and the silver thick film during the sintering, which may cause deformation. Therefore, it is preferable that the thermal shrinkage of the m-plate is as close as possible to the thermal shrinkage of the silver thick film formed by the conductive paste of the printer. As one of the reasons for the thermal shrinkage of the above-mentioned silver thick film during such firing, the silver powder in the conductive paste is generally considered to cause sintering during firing: so ... p,-the silver powder is generally considered to be composed of fine crystallites. In order to form a silver thick film, the formed polycrystalline body is sintered when the conductive paste containing rhenium is fired, and the microcrystals in the silver powder are sintered before and after the silver thick film is formed, causing thermal contraction. In order to obtain a conductive paste containing a silver powder having a small heat shrinkage, the crystallites in the silver powder are as large as possible, and it is better not to sinter the crystallites as much as possible. In addition, in recent years, the improvement of the high-frequency characteristics of the circuit # or the improvement of the dimensional accuracy of the substrate before and after firing have been required. Therefore, as a substrate for forming a silver thick film, instead of the ceramic substrate as described above, ltcc ( Low Temperature Co-fireci Ceramic: 2213-6834-PF 6 200536636 substrate. In addition, the LTCC substrate is obtained by sintering a green sheet of the LTCC substrate and a conductive paste containing a low-resistance conductor such as silver powder at the same time, so the conductive paste is printed on The technique of forming a silver-thick film on it can be completed in a small number of firing cycles, it is easy to control the thickness of the dielectric film, the electrical resistance of the circuit formed by the electrical conductivity ^ is low, and it is easy to improve. The surface of the substrate is flat; it is better from a few viewpoints. However, due to its excellent dimensional stability, even the silver powder of the conductive paste used in this LTCC is strongly required to have a smaller heat shrinkage. Because of this, large crystallites in silver powder are highly expected. . In addition, if the crystallites in the silver powder are large, the impurity content of the silver powder will generally decrease. Based on this, the specific resistance of the circuit formed by the silver thick film is easily reduced, so it is not only performed as described above. It is also preferable from the viewpoint that a conductive paste containing silver powder can be used for a formed circuit and a circuit formed by non-baking. As described above, it is desirable that the silver powder used for the conductive paste be fine particles, have good dispersibility, have a relatively narrow particle size distribution and are relatively wide, and have large crystallites. In response, the Japanese patent application (Japanese Patent Application Laid-Open No. 2000 ~ 1706) discloses the production of highly crystalline silver particles in which a silver nitrate aqueous solution and a solution in which an acrylic monomer is dissolved in an ascorbic acid aqueous solution are mixed and reacted at the same time. method. According to this method, a highly crystalline silver powder having a crystallite size of at least A and a narrow particle diameter range of 2 to 4 // m can be obtained. However, the Japanese patent application (Japanese Laid-Open Patent Publication No. 2000 ~ 1706)

2213-6834-PF 7 200536636 Although the powders are fine particles and large crystallites, the thermal contraction rate at the south temperature is difficult to match with the media. Although this kind of silver powder has very large crystallites, the thermal shrinkage rate at high temperature is still quite large. This reason is presumed that the particle size of the silver powder is in the range of 2 ~ 4 // m, and the particle size distribution is too narrow. The formation of m 'causes the filling property of the silver powder to decrease. Therefore, if it is used to make a conductive paste to form a silver thick film or to form a circuit using an LTCC substrate, the dimensional change before and after the formation of the circuit increases, and

-The problem of surface warpage is likely to occur on a ceramic substrate or an LTCC substrate, especially an LTCC & plate. Therefore, an object of the present invention is to provide a highly crystalline silver powder and a method for producing a pot, in which the particles are fine particles, have good dispersibility, have a relatively narrow particle size distribution, but are relatively broad and have large crystallites. [Summary of the Invention] In response to this fact, the present inventors conducted intensive research and found that if silver powder is prepared by mixing a second solution containing table silver, a dispersant, and acetic acid with a second aqueous solution containing ascorbic acid, , It can obtain system fine particles, the particle size distribution is not too narrow ^ relatively wide, and the crystallites are large, and the silver thick film obtained from the conductive paste can be made into a highly crystalline silver powder with excellent heat shrinkage resistance, and so on. Complete this book. That is, a method for producing a 'series-type highly crystalline silver powder, which is characterized by mixing a second aqueous solution containing silver silver, a dispersant, and lithokic acid with a second aqueous solution containing ascorbic acid. Crystallization In addition, in a method for producing a highly-crystalline silver powder, a method for producing a silver powder having a high crystallinity is characterized in that the former method is

2213-6834-PF 8 200536636 vinylpyrrolidone. Also provided is a method for producing a highly crystalline silver powder. In the above method for producing a highly crystalline silver powder, it is characterized in that [the dispersant is gelatin, and a method for producing a highly crystalline silver powder is provided. The manufacturing method is characterized in that the aforementioned first aqueous solution system is prepared with 5 to 60 parts by weight of polyvinylpyrrolidone and 35 to 70 parts by weight with respect to 100 parts by weight of silver shoot acid. In addition, a method for producing a high-junction crystalline silver powder is provided.

In the above-mentioned method for producing a crystalline silver powder having a high aqueous solution, the foregoing system is characterized in that, based on 100 parts by weight of silver nitrate, a part by weight of gelatin and 35 parts by weight to 70 parts by weight of nitric acid are blended. There is also provided a method for producing highly crystalline silver powder. In the above method for producing highly crystalline silver powder, it is characterized in that the aqueous solution before the material and the second aqueous solution are compared with the first! Formulated in aqueous solution

Parts by weight 'are mixed at a ratio of 30 parts by weight to 90 parts by weight of ascorbic acid prepared in the second aqueous solution. In addition, there is provided a method for producing a highly crystalline silver powder, wherein the crystalline silver powder and the second aqueous solution are prepared from the anti-soil-blood acid prepared from the second aqueous solution. _ Parts by weight, it is mixed at a ratio of 40 to 150 parts by weight of the true acid prepared in the second aqueous solution. In addition, a highly crystalline silver powder is provided, which is produced by a method for producing a highly crystalline silver powder. …, Based on the above, it is also a kind of highly crystalline silver powder, which is based on the above-mentioned highly crystalline silver powder

2213-6834-PF '200536636 The manufacturer is characterized in that the crystallite size is 300 A or more. Furthermore, it is a highly crystalline silver powder characterized in that the average particle diameter D 50 is 0 · 5 / z m to 10 / z m 〇 In addition, it is a samarium crystalline silver powder characterized in that it is osmium. The thermal shrinkage of C is within ± 3%. It is also a highly crystalline silver powder, which is characterized by "/ Di. It is 2 · 1 to 5_ 0. • It has a long crystallite size of 700 ° C and is a highly crystalline silver powder, which is characterized by 300 A Above, the average particle diameter is D5. It is 0 / zm ~ 10 # m, and the heat shrinkage rate in the degree direction is within 3%. And it is a kind of highly crystalline silver powder, which is characterized by: Dg &D; D 2. 1 ~ 5. 0. Effect of the Invention: The highly crystalline silver powder of the present invention is relatively loose and has a large crystallite size because the particles are fine particles, dispersed =, and the particle size distribution is not too narrow, so it is used as: The dispersibility of silver tincture and the filling property of silver-electricity-poor agents are fire, and Λ Α is quite different. It can make electrodes or circuits formed by a thick silver film more detailed. The thick silver film of the conductive paste is made of heat-shrinkable ^, ^ Be ,, and has a low specific resistance at the same time. In addition, the method for manufacturing the high-yield and silver-yin silver Qin of the present invention It is possible to effectively solve the above-mentioned highly crystalline silver powder according to the present invention. [Embodiment] (Related high crystallinity of the present invention Powder) of the present invention is related to high junction silver-based substantially - type of granular powder

2213-6834-PF 10 '200536636 Limb. The highly crystalline silver powder of the present invention has an average particle diameter h. 〇 :: ―, and 1 / z is preferred. If the average particle diameter L is within this range, when used in a conductive paste, the powder has excellent internal properties of the conductive paste. At the same time, the circuit formed by a thick silver film can be used. ^ On the other hand, the average particle diameter is d5. If it is less than 0.5 ", the recovery of silver powder is difficult, so it is not good; if it exceeds iq", there are quite a lot of aggregation situations between silver powders, so it is not good. The so-called average particle ^

The particle diameter of 50% of the volume average particle size distribution obtained by the laser diffraction scattering method.丨 Series The microcrystalline diameter of the highly crystalline silver powder system of the present invention is preferably at least 300 a. If the crystallite diameter is within this range, the electric substrate containing the poor solvent is coated on the electric substrate. The force is ... The thermal shrinkage of the substrate is similar, and the effect of suppressing the thick peeling of the silver thick film from ceramite or the deformation of the H substrate with the change of the size of the silver thick film is quite large, so it is preferable. In terms of Taoism, if the crystallite diameter is less than 300 Å, a thinner containing the silver powder is coated on a ceramic substrate and baked to form a circuit made of a thick film of silver, etc. The shrinkage of the silver thick film is larger than that of Tao Wu: the shrinkage of the plate is larger, or the silver thick film is easier to peel off from the ceramic substrate. The ceramic substrate is easily deformed with the change of the size of the silver thick film. The crystal diameter refers to the average value of the diameters obtained from the half-value width of the peak of the diffraction angle of each crystal plane, which is obtained by testing the χ㈣ diffraction of the silver powder.

2213-6834-PF 11 200536636 Regarding the highly crystalline silver powder system of the present invention, Ds () / D "is usually 2.1 to 5.0, and preferably 2.5 to 4.7. Furthermore, in the present invention, κ. And" are each Do not indicate the median particle size (_. ^ / Di.) Of the cumulative distribution based on the laser diffraction scattering particle size distribution measurement method of 10% by volume and 90% by volume. A large value indicates a large degree of unevenness in the particle size distribution. When DWD4 is within the above range, the particle size distribution of the silver powder is not too narrow and relatively wide, and if the conductive paste using the silver powder is used to form a circuit, Because silver powder has excellent filling properties, the heat shrinkage resistance of the circuit is likely to be the second best, that is, the size change of the circuit before and after burning is easy to be better, and on the other hand, if 'WDh is less than 2. The particle size distribution of the silver powder is too steep. If the conductive paste of the silver powder is used to form a circuit, the powder has a poor filling property, so the heat shrinkage resistance of the circuit is likely to be poor, that is, before and after firing. The size of the circuit changes easily to become larger, WD】. If it exceeds 5.0, the particle size distribution of silver powder is too wide ^: = powder = electrical paste to form a circuit, because the silver powder is filled! · Poor performance, so the heat resistance of the circuit is poor. The change in the size of the circuit before and after firing tends to become the larger one, which is not good, that is, the heat direction of the cultured silver powder is less than 7% ° C, and the soil is preferably less than 2% in length. In the present invention, the so-called within ± x%; the so-called mv / x%. In the present invention, the sample of the pellet, thermomechanical analysis ⑽)

2213-6834-PF 12 200536636 Thermal shrinkage in the direction. Regarding the high-crystalline silver powder of the present invention, the electrical properties of the silver coating film baked at ° C are relatively low temperature, for example, 300 crystalline silver powder is sintered and sintered: two 'Even if the high junction is made at low temperature, the sintered: = is the lower one. Furthermore, it is presumed that the reason why the movement of = 1 is relatively smooth for the reason that the crystallite diameter is large and the silver powder Mastiff is low. O.lOmVg ~ 1.0 ffi2 / g, @ n 9n 2 / 糸 specific surface area is usually

And if the area of 〇20m / g ~ 0.99mV is less than 0.10m2 /, this ratio g is difficult to refine due to the thinning of electrodes or circuits based on the silver thick film, so the precision of the electric circuit 2 / ^ Nephew. If the specific surface area exceeds 10

m / g, it is not good because the paste U of the silver powder is difficult to be used for the main application. In the present invention, the monthly specific surface area refers to the bet specific surface area. Related to the present invention: Japanese, Japanese, Japanese, Japanese silver powder, tap density is usually 3. 8/3 p private Φ-1-life / up, and 4. · Og / cm3 ~ 6 · 0g / cm3 If the tapdensity is within this range, then the high crystallinity silver powder towel ## ^ &% is easy to produce a conductive paste with good filling properties, and ^ and When forming a coating film of a conductive lean agent, by forming a moderate gap between highly crystalline silver powders, when the coating film is fired, the deliming from the coating film is easily performed, and the density of the fired film is improved. It is preferable to reduce the resistance of the silver thick film. The highly crystalline silver powder of the present invention can be produced by, for example, the following method. (Production method of the highly crystalline silver powder of the present invention) The production method of the highly crystalline silver powder of the present invention is a method for the i-th aqueous solution containing silver lithionate, a dispersant, and nitric acid, and ascorbic acid

2213-6834-PF 13 200536636 The second aqueous solution is mixed. In the present invention, the so-called first! An aqueous solution is an aqueous solution containing silver nitrate, a dispersant, and lithocholic acid. Y order &-φ) ^ I t material, weekly water-based pure water, ion-exchanged water, ultrapure water, etc. used in the aqueous solution are preferable because impurities are prevented from being mixed into the silver powder. The silver nitrate used in the present invention is not particularly limited, and either a solid state or an aqueous solution can be used.

Examples of the dispersant used in the present invention include polyethylene (MP), gelatin, polyethylene glycol, and polyvinyl alcohol. In addition, in the present invention, a gelatin system is used by including epiphysis µ. Among the dispersants used in the present invention, ethyrenone and gelatin are particularly preferred because they can improve the heat shrinkage resistance of silver powder. In the present invention, by dispersing the dispersant in the i-th aqueous solution ', the dispersibility of the silver powder can be improved, and at the same time, the silver powder-based fine particles have the effect of making the particle size distribution not too narrow and relatively relaxed. The nitric acid used in the present invention is not particularly limited, and either concentrated nitric acid or dilute nitric acid can be used. In the towel of the present invention, since nitric acid is blended in the first aqueous solution, the reaction rate for generating silver from silver ions can be controlled to be relatively slow. Therefore, the particle size distribution of the silver powder is not too narrow and is slower than that of the car. And increase the role of microcrystals. In addition, if silver powder is produced without the preparation of nitric acid, the reaction rate of producing silver from silver ions is too fast and the reaction occurs immediately. Therefore, the obtained silver powder is more likely to become granules than the case where nitric acid is prepared by the preparation of the present invention. The diameter is smaller and the crystallite diameter is smaller. When the first aqueous solution is a polyvinylpyrrolidone as a dispersant, it usually contains 5 parts by weight of polyvinylpyrrolidone relative to 100 parts by weight of silver nitrate.

2213-6834-PF 14 • 200536636 to 60 parts by weight, and 15 to 50 parts by weight are more preferred. Polyethylene glycol is two parts by weight 'due to the improved dispersion of silver powder: in the Seoul', it is not too narrow and is relatively wide, so it is easier to make the particle size distribution into the amount of ketoketone if it is less than 5 The weight of noodles is not good because it is easy to agglomerate; if it exceeds 60 parts by weight = the concentration of impurities in the obtained silver powder content is likely to be high, and the content is too high; Easy 5 wooden brother, easy production cost " two Γ: = when the dispersant is gelatin, the phase material ^? Two gelatin °. 5 parts by weight, parts by weight and 1 ~ 8 parts by weight is better, 2 The weight is better if the weight is within 竽 笳 π. Within the blending of gelatin, the dispersion of the silver powder is improved, and the distribution of the same powder is easy to become too narrow and not too narrow: On the other hand, if the blending amount of gelatin is small It is easy to agglomerate, so it is not good. If it exceeds the concentration of impurities, it is easy to be high. Rongji == The production cost valley is easy to be high, so it is not good. The brother-in-law / healing liquid knife release agent is polyethylene gallidine g. At the same time, the weight of the phase water is usually about 1 part by weight, and ^ parts by weight is better than 4 parts by weight. . Within the range of the blending of Poly-E-Women, it is better because the dispersibility of silver powder is improved, and the silver consumption is easy to become not too narrow and wide, so it is better. In addition, if the blending amount of polyvinylpyrrolidone is less than 1 part by weight, it is not good because the silver powder is easy to agglomerate; if it exceeds 10 parts by weight, then:

2213-6834-PF 15 .200536636 The impurity concentration in the silver powder is easy, and the cost is easy to be high, so it is not good. = ^ h ^ In fact, the production of the first aqueous solution system, the dispersant is bright parts, usually contains gelatin 〇 ″ by weight " at 7 " ° 〇wt ~ 2 R ^ Know ~ 5 parts by weight, and 0.4 parts by weight Two-layer knowledge is better. The dispersion of gelatin is improved, and at the same time, the size of the silver powder is not likely to be too small due to the particle size distribution of silver powder, ^ η 1. 0 v On the other hand, if the amount of gelatin is small, then Because the obtained silver powder is easy to agglomerate, it is not good; = 4 parts by weight, the concentration of impurities in the silver powder obtained from osmium tends to be biased ... It is easy to pollute the environment and the production cost is easily high, so it is not good. The aqueous solution is based on 500,000 parts by weight of silver acid, and usually contains 35 parts by weight of nitric acid to 70 parts by weight. 70 parts by weight, preferably 40 parts by weight to 60 parts by weight, 48 parts by weight Serving ~ 54 Huijing / Eight words, soil, Ricci pregnancy 77 more ^. If the amount of the nitric acid to be blended is within this range, it is preferable because the particle size distribution of the silver powder is not too narrow and is relatively wide, and the effect of increasing the crystallites is large. On the other hand, if the blending amount of lithocholic acid is less than 35 parts by weight, the crystallinity of the silver powder tends to be low, which is not good. If it exceeds 70 parts by weight, the obtained silver powder is likely to aggregate, so it is good. In addition, in the present invention, the amount of nitric acid to be mixed refers to the amount of concentrated nitric acid which is 61%. In the present invention, the second aqueous solution refers to an aqueous solution containing ascorbic acid. Water-based pure water, ion-exchanged water, ultrapure water, and the like used for preparing the second aqueous solution are preferable because impurities are prevented from being mixed into the silver powder. As the ascorbic acid used in the present invention, either of L-isomer and D-isomer can be used. In the manufacturing method of the present invention, the second aqueous solution and the second aqueous solution are mixed

2213-6834-PF 16 • 200536636 Liquid B is used to analyze the highly crystalline silver powder in the mixed solution. For example, the method of stirring the first aqueous solution and then changing the first:-'first aqueous solution can be mentioned. In this case, as the 2 = Γ method, you can add all of the 力 2 hydraulic, /, and liquid mixtures to the 1st, 1st, 6th, and 6th. The second aqueous solution can be slowly added in small amounts at a time. The dispersant in the i-th water volume, the second, and the first aqueous solution is poly ~, and then the hydrazone? f. When Liuping talks about the outline, if the method of adding the whole # 22 to the first aqueous solution is used, it is better because of the reason. When "Don't cause Taicha Λ" relatively loose silver powder, water = two When the dispersant in: is gelatin, if the method of slowly adding the second easy-to-make: ^ li to the first aqueous solution is adopted, it is preferable to control the particle size of the silver powder, so it is better to mix the first aqueous solution with The second water-soluble 1 κ ^ ^ 4 and you are 100 parts by weight of silver nitrate prepared in the first water solution, 浐 A 、, s A j 扪 The ascorbic acid fcc is usually 30 parts by weight in the brother 2 aqueous solution. ~ 9〇 詈 ^ Bahit Kogami cn Ruri 40 parts by weight ~ 80 parts by weight "~ 75 parts by weight are mixed at a better ratio. Blended with ascorbic acid relative to silver nitrate The yield of silver powder tends to increase, so it is preferred. Another = :, because 1 nn Tongdan Bafang 'relative to silver nitrate reduction Λ blood acid preparation amount is less than 3G parts by weight, because the yield of 100, heavy-second powder is easy to be low, so it is not good; If the amount of ascorbic acid is more than 90 parts by weight relative to the silver oxalate and razor blade, it is not good because it is easy to pollute the environment and the production cost is easily high. "I said that when the first aqueous solution and the second aqueous solution were mixed, the" concentration of silver ions in the solution is usually, and the ratio of 30 g / 1 to 65 W is better. The silver ions in the mixed solution are rolled. If the degree

2213-6834-PF 17 200536636, it is better because the yield of silver powder is higher. On the other hand, the silver powder with strong silver ions is difficult to coagulate / Chen degree is less than 1 (). The productivity of silver powder is easily deteriorated, so it is not good; silver and g / bu are easily aggregated due to the obtained silver powder. More than 80 κ is bad for the enemy. The second χ, heart: Brother 1 water * solution and Brother 2 aqueous solution, relative to the ascorbic acid 1000 weight formulated in Brother 2 Shui Luo solution 丨 Swordfish "Zhou Bei" in the first fire, mysterious, and state of stone The oxalic acid is usually 40 to 150 parts by weight, preferably 65 to 100 parts by weight. The ratio of the blending ratio of the ascorbic acid nucleus to the silver powder is likely to increase, so it is more effective. In addition, within the range of consumption, if the blending amount of shithoic acid is 100 parts by weight of blood acid, if it is small: 40% of denier is difficult to change the crystallite diameter of the obtained silver powder. The side blending amount of parts by weight: over = weight T, because the obtained silver powder is easy to agglomerate, it is not good. It is known that based on mixing the first aqueous solution and the second silver powder, the first aqueous solution and the second aqueous solution are soluble :: : = Precipitation in the mixture is usually continued for 3 minutes by mixing the mixed solution. It is :: most: 2. If you borrow another minute to make the palladium steak in the mixed solution, take it back for 5 minutes ~ 10 The dispersibility is easy to be two … Then the particle size and particle size distribution of silver powder are better. Within the specific range of mixed silver powder, the meaning of τ Filtering devices such as silver powder are pure: if you use a funnel to dry, you can get the high crystallinity of the present invention = washing the heart. You can dry the high crystallinity silver powder chip element and plasma display panel of the present invention. It can be used to form,

2213-6834-PF 18 200536636 The original family of conductive pastes for pens or circuits ^ Especially the thermal shrinkage of silver powder is very small, not only can it be used as a general ceramic substrate for circuit formation The substrate is a raw material that can be used as a conductive paste for LTCC substrates. In addition, the manufacturing method of the south crystalline silver powder indicated by Tai # 一 啕 Sekimoto can be used for the production of the same crystalline silver powder of the ancient part of the present invention. Although the following is a description of the examples, the present invention is not limited to the explanations of these examples. I. [Example 1] Put 500 g of PVP (K value: 30), 50 g of silver nitrate, and cinnabarium (concentration 61%)% 6 in 500 g of pure water at room temperature. Modulation Cap! Aqueous solution (Cap! Aqueous solution A). On the other hand, 35.8 g 'of human ascorbic acid was placed in pure water_g at room temperature, and stirred to dissolve to prepare a second water solution (second aqueous solution A). The composition of the aqueous solution and the second aqueous solution is shown in Tables 1 and 2. /. While the first aqueous solution A is being stirred, a second aqueous solution A- is added to the second aqueous solution A ', and the mixture is stirred for 5 minutes after the addition is completed to grow the particles in the mixed solution. Thereafter, the stirring was stopped, the particles in the mixed solution were allowed to settle, and the upper clear solution of the mixed solution was discarded. The mixed solution was filtered using a Knoop funnel, the filter residue was washed with pure water, and dried to obtain highly crystalline silver powder. About the obtained silver powder, Diq, Ip D ", Dm, SD, crystallite diameter, specific surface area, tap density, thermal shrinkage, and resistivity were measured by the following methods, and L ^ / Dh was calculated. The results are shown in Table 3 ~ As shown in Table 6. (D! 〇, D5., D9〇, Dioo, SD) ·· Used by Nikkiso Co., Ltd.

2213-6834-PF 19 .200536636 MICROTRAC-HRA The particle diameters at the time points of 10%, 50%, 90%, and 1 (0%) of the cumulative distribution obtained by the laser diffraction scattering method. Set to D !. (# M) D5 () (# m), j) 9. (# M D⑴ (# 爪), and the standard deviation of the obtained particle size distribution is SD. (Crystalline diameter): The powder X-ray diffraction was performed by using a X-ray diffraction device RINT2 0 0 0PC manufactured by Rigaku Corporation. Analyze and obtain the crystallite diameter from the half width of the peaks of the diffraction angles of the crystal planes obtained. (Specific surface area) · The BET specific surface area is measured by using ASA⑽, manufactured by YUASA Ionics Corporation. &Amp; βΕΤ specific surface area. (Fe tap density) · The tap density was measured by tapping the sample with a tapping machine made by Zangji Scientific Machinery Co., Ltd. (Heat shrinkage rate): Pressing the silver powder to Making cylindrical pellets, using

TMA / SS6300 manufactured by Seiko Instruments Inc. was subjected to TMA analysis in the air at a temperature rise rate of 1 (rc / dn from normal temperature to 85 (rc), and the heat in the longitudinal direction of the pellet was measured. Shrinkage rate measurement temperature is set to 30 (rc, 50 (rc, and 70 (rc.)) (Resistivity): 95 parts by weight of onionol and 5 weight of ethyl cellulose, which is a mixed solvent made in 5 weeks. '15 parts by weight of this mixed solvent is mixed with 85 parts by weight of powder sample to prepare a paste, and the paste is fired at 300 ° C to produce a silver coating film having a thickness of about several meters. A silver coating film was produced in the same manner as above except that the firing temperature was set at 300 C to 400 T: and 500 T :. Next, 'Using (Hewlett — Packard Co., Ltd. MILL10ΗM METER)' was obtained by a four-terminal network method. Measure the resistance (Ω) of the silver coating film

2213-6834-PF 20 200536636, (Ω is calculated from the cross-sectional area of the silver coating film and the length of the terminal to obtain the resistivity ρ L. Example 2 j Pvp rg in 500 g of pure water at room temperature Y put 20 g of PVP (K value: 30), 50 g of silver nitrate, and concentrated nitric acid (concentration%) degree bU) 24.6 §, and stir to dissolve to prepare a first aqueous solution (first water-soluble) from β) On the other hand, Ascorbic acid (8 g) was placed in 500 g of pure water at room temperature, and the mixture was stirred and dissolved to prepare a second aqueous solution (second aqueous solution a). 1st, 2nd, 6th

The composition of the 1st water solution and the second aqueous solution is shown in Tables 1 and 2. Next, while stirring the ribs of the first aqueous solution B, the second aqueous solution A is added to the first, second, right, and right sides of the first aqueous solution B. After the addition is complete, stir again 5 'to make the particles in the dagger liquid grow. After that, stop teaching, settle the jinzi in the mixed solution, and discard the upper clear solution of the mixed solution. # Use a nutrient funnel to purge the mixed solution, wash the filter residue with pure water, and dry it to obtain high crystallinity. Silver powder. The obtained silver powder was implemented in the same manner as in Example 1, and t Dh, d50, and D9 were measured by the above method. , D〗. . , SD, crystallite diameter, specific surface area, tap density, thermal shrinkage, and resistivity are calculated as A D9〇 / D. The results are shown in Tables 3 to 6. [Comparative Example 1] 10 g of PVP (K value: 30) and 50 g of silver nitrate were placed in 50 g of pure water at room temperature and stirred to dissolve to prepare a first aqueous solution (first aqueous solution C). On the other hand, 26 g of ascorbic acid was placed in 500 g of pure water at room temperature, and it was searched and dissolved to prepare a second aqueous solution (second aqueous solution B). 1st

2213-6834-PF 21 200536636

The compositions of the aqueous solution and the second aqueous solution are as shown in Tables j and 2. Q The human being, while stirring the first aqueous solution c, added the second aqueous solution β- to the first aqueous solution C, and After the addition is complete, stir for 5 minutes to grow the particles in the mixture. After that, the mixing was stopped, the particles of the mixed solution were allowed to settle, and the upper clear solution of the mixed solution was discarded. The mixed solution was filtered using a Knoop funnel, washed with pure water, and dried to obtain silver powder. The obtained silver powder was implemented in the same manner as in Example i, and ^, ^, and 'were measured by a method. , ^, Crystallite diameter ~ specific surface area, tap density, thermal shrinkage and electrical resistivity, calculate w ". The results are shown in Tables 3 to 6. [Example 3] 250 g of pure water at room temperature Into gelatin (made by Nitta Gelatin Co., Ltd.) i.〇g, silver nitrate 50§ and concentrated hyaluronic acid (concentration 6i%) 26 4g, the first aqueous solution (the first j ^ 令 液 D) On the other hand, ascorbic acid 26. 4 = was placed in 25 g of pure water at room temperature, and stirred to dissolve to prepare a second aqueous solution (the second aqueous solution, the first aqueous solution and the second aqueous solution. The composition is shown in Tables 2 and 2. —Secondly, under the condition that the first aqueous solution D is taught at 50 ° C, the younger 2 water mixture c at room temperature is slowly added to the first 30 minutes. ] In the aqueous solution d, the mixture was allowed to grow for 5 minutes after the addition was completed to grow the particles in the mixed solution. After that, the mixing was stopped. The particles in the mixed solution were allowed to settle and the upper layer of the mixed solution was discarded.遽 Mix the liquid, rinse with pure water and apply

Dry to obtain highly crystalline silver powder. 2213-6834-PF 22 200536636 The obtained silver powder was implemented in the same manner as in Example 1, and t Di0, D5d, and d9 were measured using the above method. , Di. . , SD, crystallite size, specific surface area, tap density, thermal shrinkage, and resistivity, and D90 / D1G was calculated. The results are shown in Tables 3 to 6. [Example 4] Gelatin (made by Nitta GELATIN Co., Ltd.) 3.0 g, silver nitrate 50 g, and concentrated nitric acid (concentration 61%) 24-6 g were placed in 50 g of pure water at room temperature, and heated to 5G. The mixture was stirred at ° C and dissolved to prepare an i-th aqueous solution (the "water" hydration solution E). On the other hand, 25 · 9 g of ascorbic acid script was placed in 500 g of pure water at room temperature, and the mixture was stirred to dissolve to prepare a second aqueous solution (a second aqueous solution, a first aqueous solution), and a composition of the valley liquid and the second aqueous solution was as follows: Tables 1 and 2 show. ^ / 、 People ’at a state of stirring the first aqueous solution E at 50 C,

The aqueous solution D is slowly added to the first aqueous solution E over 30 minutes, and the mixture is stirred for 5 minutes to grow the particles in the mixed solution. After that, the stirring was stopped, the particles in the mixed solution were allowed to settle, and the upper layer of the mixed solution was discarded for clarification. The mixed solution was filtered using a Knoop funnel, the filter residue was washed with pure water, and dried to obtain highly crystalline silver powder. The obtained silver powder was implemented in the same manner as in Example 1. Using the above, Dl °, D5G, D9i), Dl °, SD, crystallite size, specific surface area, tapping degree, thermal shrinkage, and Resistivity, calculate $ D9 " Di. . The results are shown in Tables 3 to 6.

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[Table 1] Type of water (g) Dispersant Dispersant (g) Silver nitrate (g) Concentrated nitric acid (g) Type of the first aqueous solution Example 1 500 PVP 10 50 24.6 A Example 2 500 PVP 20 50 24.6 B Comparative Example 1 500 PVP 10 50 0 C Example 3 250 Gelatin 1.0 50 26.4 D Example 4 500 Gelatin 3.0 50 24.6 E

[Table 2] Water (g) Ascorbic acid (g) Type of second aqueous solution Example 1 500 35.8 A Example 2 500 35.8 A Comparative Example 1 500 26.0 B Example 3 250 26.4 C Example 4 500 25.9 D [No. Table 3] Dio (um) D50 (#m) D90 (Um) D100 (// m) D90 / D10 SD Example 1 2.97 6.35 10.75 22.0 3.6 3.01 Example 2 1.30 3.03 5.67 15.6 4.4 1.59 Comparative Example 1 2.14 2.83 4.08 9.3 1.9 0.71 Example 3 2.72 4.36 7.33 18.5 2.7 1.71 Example 4 0.76 1.27 2.28 4.6 3.0 0.57 [Table 4] Crystallite diameter (A) Specific surface area (m2 / g) Tap density (g / cm3) Example 1 441 0.30 4.1 Example 2 377 0.62 4.0 Comparative Example 1 258 0.62 3.8 Example 3 545 0.20 4.4 Example 4 441 0.72 4.8 2213-6834- PF 24 200536636 [Table 5] Thermal shrinkage at 300 ° C (%) Thermal shrinkage (%) at 500 ° C Thermal shrinkage (%) at 700 ° C Example 1 0.13-2,13-2.2 Example 2 0.09-2.68-2.9 Comparative Example 1 0.84 -4.02 -7.82 Example 3 0.27 1.08 1.13 Example 4 -0.58 ~~ 1.51 ~ 1.35 [Table 6] Resistivity ρ of the silver coating film fired at 300 ° C ( M) Resistivity ρ (Ω · m) of the silver coating film baked at 400 ° C Resistivity ρ (Ω · m) of the silver coating film baked at 500 ° C Example 1 4.1 ΧΙΟ'5 2.0 xlO · 5 9.9 xlO · 6 Example 2 5.2x10'5 1.5 x χ 10'5 1.2 xlO'5 Comparative Example 1 7.2 xlO * 4 8.9 χ1 (Τ6 4.8 χΐσ5 Example 3 9.4 χIO'6 8.3 xlO'6 9.9 xlO * 6 Example 4 1.0 xlO · 5 8.8x10'6 4.8 xlO'5 It can be judged from Tables 1 to 5 that the silver powder based on the use of a dispersant and nitric acid has a large crystallite size and high crystallinity. 〇. The thermal contraction rate of 〇 is small. And it can be judged that those who use gelatin as a dispersant, especially in? The thermal shrinkage of 〇 C is small. From Table 6, it can be determined that the resistivity p of the silver coating film at 300 t: yttrium k is lower than that of the silver powder prepared without using nitric acid, compared to the silver powder prepared without using nitric acid. This reason is presumed to be based on the fact that the movement of electrons in the roughly silver powder of the micro-diameter wheel is relatively smooth. Industrial applicability: The manufacturing method of the highly crystalline silver powder and the highly crystalline silver powder according to the present invention is sufficient for forming electrodes such as wafer elements, plasma display panels, glass ceramics, and ceramic filter It can be used as a raw material for conductive pastes for circuits or circuits, and is particularly suitable as a raw material for conductive pastes for LTCC substrates. 2213-6 ^ 34-Pp 25 200536636 [Simplified illustration of the diagram] None [Description of the main component symbols] None

2213-6834-PF

Claims (1)

* 200536636 10. Scope of patent application: 1 · Made of a highly crystalline silver powder A second aqueous solution containing silver nitrate, a dispersant and blood nitrate is mixed. The manufacturing method is characterized in that: the first aqueous solution and the anticorrosive method are included. 2. The manufacturing method of the highly crystalline silver powder as described in the first patent application claim is negative, wherein the dispersant is polyvinylpyrrolidone. 3. The method for producing a highly crystalline silver powder according to item 1 of the scope of patent 1, wherein the dispersant is gelatin. 4. The method of manufacturing highly crystalline silver powder as described in item 2 of the new patent application and + Gule z, where the first water, liquid, and liquid are used, as compared with silver nitrate, 1 0 0 parts by weight, then polyvinylpyrrolidone is prepared in 5 parts by weight, 60 parts by weight in the chamber, 35 parts by weight of nitric acid, and 70 parts by weight. // As described in the patent claim No. 3 of the patent scope for the production method of high crystallinity silver powder /, the first aqueous solution described in Zhonggang, with respect to the weight of authentic acid silver, it is blended with 0. 5 parts by weight of knees ~ 1 nf β eight denier cut 10 parts by weight, 35 parts by weight of nitric acid ~ 70 parts by weight. 6. The method for manufacturing a highly crystalline silver powder according to item 1 of the scope of the patent application: wherein the first aqueous solution and the second aqueous solution are composed of silver nitrate prepared in the aqueous solution of the reference 引 1. Parts by weight are mixed at a ratio of 30 parts by weight to 90 parts by weight of ascorbic acid prepared in the second ruler / mixture. The method of manufacturing the highly crystalline silver powder as described in item (i) of the scope of the patent application, wherein the first aqueous solution and the second aqueous solution are the second aqueous solution of the first, second, sixth, and sixth phases. 1003 parts by weight of ascorbic acid formulated in the mixture, 2213 -6834-PF 27 • 200536636 1 50 parts by weight are mixed with a proportion of 40 parts by weight of nitric acid formulated in the first aqueous solution as applied for a patent. . 8-A kind of crystalline silver powder, characterized in that: I 制造 is produced by the method described in item 1. 9. If the scope of patent application is No. 8, the crystallite diameter is more than 300 A. The highly crystalline silver powder wherein 10. The highly crystalline silver powder according to item f8 of the Chinese Patent Application, wherein the average particle diameter is. (Where ^ represents the cumulative distribution based on the laser diffraction scattering particle size distribution method, 50 volume% median particle size (#m)) η. The highly crystalline silver powder as described in item 8 of the patent application scope, where The thermal contraction rate at 700 ° C is within ± 3%. 12. For example, the highly crystalline silver powder described in item f 8 of the patent, of which IWD. For 2. Bu 5. 〇. (In the previous formula, Di. and &. respectively represent the cumulative distribution ig volume% and 90 volume% median particle size (# 以) based on the laser diffraction scattering particle size distribution measurement method. 13. A high The crystalline silver powder is characterized in that the crystallite diameter is 300 m or more and the average particle diameter Ds is 0.5 · m / m ~ 10 # m, and the thermal shrinkage rate in the longitudinal direction at 7000c Within ± 3%. 14. Highly crystalline silver powder as described in item 13 of the scope of the patent application, where D90 / D1d is 2; 1 to 5.0. (And in the previous formula,)) 1 () and D9. It represents the cumulative distribution based on the laser diffraction scattering particle size distribution measurement method. 10% by volume and 90% by volume median particle size (# πι)) 2213-6834-PF 28 200536636 VII. Designated representative map · · (I) The designated representative map in this case is: None (II) The component symbols of this representative map are simply explained: None 8. If there is a chemical formula in this case, please disclose the chemical formula that best shows the characteristics of the invention: 2213-6834-PF 4