TW200540885A - Method for preparing non-magnetic nickel powders - Google Patents

Method for preparing non-magnetic nickel powders

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Publication number
TW200540885A
TW200540885A TW93115905A TW93115905A TW200540885A TW 200540885 A TW200540885 A TW 200540885A TW 93115905 A TW93115905 A TW 93115905A TW 93115905 A TW93115905 A TW 93115905A TW 200540885 A TW200540885 A TW 200540885A
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Taiwan
Prior art keywords
nickel
mixture
step
item
nickel powder
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TW93115905A
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Chinese (zh)
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TWI234789B (en
Inventor
Soon-Ho Kim
Jae-Young Choi
Eun-Bum Cho
Yong-Kyun Lee
Seon-Mi Yoon
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Samsung Electronics Co Ltd
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Publication of TWI234789B publication Critical patent/TWI234789B/en
Publication of TW200540885A publication Critical patent/TW200540885A/en

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Abstract

Provided is a method for preparing non-magnetic nickel powders. The method include (a) heating a mixture including a nickel precursor compound and a polyol to reduce the nickel precursor compound to nickel powders with a face-centered cubic (FCC) crystal structure, and (b) heating the resultant mixture of step (a) to transform at least a portion of the nickel powders with the FCC crystal structure to nickel powders with a hexagonal close packed (HCP) crystal structure.

Description

200540885 IX. Description of the invention: [Technical field to which the invention belongs] The present invention relates to a non-magnetic nickel powder and a manufacturing method thereof. [Prior art] Nickel is a transition metal, belonging to the iron group of the fourth period of the eighth group of the periodic table, and is a crystalline substance with a high melting point and excellent ductility. Nickel powder is a granular metallic nickel material that can be used as, for example, materials for internal electrodes in electronic devices (such as multilayer ceramic capacitors (MLCCs)), magnetic materials, electrical contact materials, and electrical conduction Adhesive material (conductive adhesive material), or catalyst (catalyst). Nickel is known as a typical ferromagnetic substance. Ferromagnetic substance means that under the condition of an external magnetic field, the substance will have a strong and continuous magnetization. Even when the external magnetic field is removed, the magnetization still exists. When a ferromagnetic substance that has not been magnetized is exposed to a gradually increasing magnetic field, ‘100 first will slowly generate magnetization, which is the so-called initial magnetization. Subsequently, the rate of magnetization will increase and a 200540885 saturation phenomenon will occur. If the intensity of the external magnetic field is reduced during the saturation phenomenon, the magnetization will be weakened. However, the process of weakening magnetization is not the same as the process of increasing magnetization. In addition, when the external magnetic field weakens to zero, the magnetization does not disappear ', which is the so-called residual magnetization. If the direction of the external magnetic field is reversed and the strength of the reverse magnetic field is increased, the magnetization will stop and the direction of the magnetization will be reversed. After that, the reverse magnetization gradually became saturated. At this time, even if the intensity of the applied magnetic field is zero, the magnetization is not zero and the reverse residual magnetization exists, so a closed curve is generated that does not pass through the origin. This closed curve is called a magnetization curve. The magnetization curve is closely related to the magnetic domain structure. Generally speaking, magnetic moment is one of the factors that cause magnetization. It is caused by parallel electron spins, and usually ferromagnetic substances have a larger magnetic moment. In addition, it is generally considered that a ferromagnetic substance has a magnetic region, and the magnetic region is a dusters of parallel spins. When a magnetic field is applied, the magnetic fields are aligned in the direction of the magnetic field. Even when the magnetic field is removed, the direction of the magnetic field remains unchanged for a long time, resulting in residual magnetization (residualmagnetization). In this regard, when the temperature of the ferromagnetic substance rises, the arrangement of the electron spins in the ferromagnetic substance is disordered due to thermal motion. Therefore, a ferromagnetic substance loses ferromagnetism and is converted into a paramagnetic substance. This temperature is called Curie temperature. The magnitude of the reverse magnetic field required to reduce the magnetic flux density to zero is called the coercive force. 200540885 The magnetic properties of bulk nickel are as follows: Curie temperature is about 353 < t, saturation magnetization is about 0.617 T, residual magnetization is about 0.300 T, and the magnitude of coercive force Approximately 239 A / m. So far, allotrope of nickel can be divided into metallic nickel having a face-centered cubic (FCC) crystal structure and metallic nickel having a hexagonal close packed (HCP) crystal structure. Almost common nickel powders are ferromagnetic substances with a face-centered cubic crystal structure. Few reports have been made of nickel powders having the hexagonal closest-packed crystal structure. Nickel powder with the hexagonal closest-packed crystal structure has long been predicted to be also a ferromagnetic substance. According to Stoner theory, DA Papaconstantopoulos et al. Predicted that nickel in the hexagonal close-packed crystal structure must be a ferromagnetic substance (see DA Papaconstantopoulos, JL Fry, NR Brener, Ferromagnetism in hexagonal close packed elements ", Physical

Review B, Vol. 39, No. 4, 1989 2.1, pp 2526-2528). As mentioned earlier, the most representative application of nickel powder is as an internal electrode in an electronic device. However, the conventional ferromagnetic nickel powder has the following disadvantages: First, it is used when forming nickel internal electrodes by printing. When the nickel powder contained in the electrode paste is magnetic, the nickel powders attract each other due to their magnetic properties, forming a structure similar to a magnet and agglomerated structure, and it is difficult to form a uniform electrode paste. Secondly, with the development of mobile communication and computer technology, electronic devices have used 200540885 ultra-high bandwidth. Thin, although it has high impedance at this high frequency, it is difficult to apply it to such injuries. These problems can be solved by using non-magnetic nickel powder. SUMMARY OF THE INVENTION Accordingly, the present invention provides a method for making non-magnetic nickel powder. According to one aspect of the present invention, the method for making non-magnetic nickel powder provided by the present invention includes the following steps: ⑻ heating-spectrum compound, and the dispersant includes-nickel precursor compound and a multicomponent Alcoholic coffee is used to convert the precursors of the pre-recorded compound to the gold raisin powder with a face-centered, cubic crystal structure; and the aging products obtained by the heating step, at least-part of the nickel powder with the crystal structure of the prescription is converted into The hexagonal nickel powder with the most densely packed crystal structure. [Embodiment] φ The present invention provides a method for manufacturing non-magnetic nickel powder, including the following steps: ⑻ heating-a mixture containing a nickel precursor compound and a polyhydric alcohol to make the secret drive compound Gu is a metal powder with a surface formula (FCQ crystal structure; and (b) the mixture obtained in the heating step ⑻ to convert at least a portion of the nickel powder with a face-centered cubic crystal structure into a hexagonal closest-packed crystal structure of 200540885 Nickel powder. The study of this month and the month of the month found that when t-like magnetic substances have an FCC phase and the knife is heated in το alcohol, it will change from fcc crystal structure to π? Crystal structure, and so on Based on these observations, the present invention uses the conventional method of making powder, that is, the nickel precursor compound is converted into FCC powder in the presence of a polyol as a reducing agent. Combined with the Fcc solution of the decomposed towel, it is completed as a series of steps in combination with the Hcp record. In short, the present invention provides a method for preparing non-magnetic nickel powder from a compound that is non-magnetic. Although the present invention is not The reason why the powder of the polyol t is transformed by heating is explained, but it is most likely because the metallic nickel dissolved in the polyol will undergo recrystallization or reduction. Even if the mechanism of __ is not confirmed, the The effectiveness of the invention should not be affected by this. There are no particular restrictions on the precursor compounds, as long as they are nickel-containing compounds that can be reduced to polyols by metal polyols. In other words, antimony compounds include antimony Oxide_) or niekel salt. Examples of Gu include sulphuric acid, nickel sulfate, nickel chloride, desertification, nickel fluoride, acetic acid, ethyl acetate, etc. These nickel precursor compounds can be used alone or in combination. Polyols are used as solvents to dissolve nickel precursor compounds. Polyols are also used as reducing agents to reduce nickel precursors to metallic nickel. Polyols—An alcohol compound 200540885 with two or more hydroxyl groups. An example of the use of a polyhydric alcohol as a reducing agent is described in U.S. Patent No. 4,539,041. For example, the polyhydric alcohol may be a glycol of a glycol (did) or an aliphatic glycol (polyglycol). Examples of the aliphatic glycol include an alkylene with C2_C6 as a main chain. Alkylene glycols 5 6J = .g | (ethanediol) ^ i ^^ g | (pr〇panediol) -butanediol, pentanedioi, and hexanedi 〇1), and polyalkylene glycol (yalkylenegly Cois) derived from alkylene giycois, such as polyethylene glycol (such as postal coffee milk). In addition, examples of aliphatic glycols may further include diethylene glycol (glycol), triethylene glycol (glycol), and propylene glycol (glycol). The alcohol can also be glycerol. Glyeen 1), which is a kind of triol ㈣〇. However, the type of the polyol of the present invention is not limited to the above-mentioned polyols, and the above-mentioned polyols can be used alone or in combination. It is worth noting that the preferred aspects of the polyhydric alcohols of the present invention are ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, [2] propylene glycol, and editing, Alcohol (P-diol-1, 3), propylene glycol (dipropylene office cO1), 0 butanediol (butanediol cut, butanediol as the secret 0 (butanedid-W), or 2 , 3_butanediol (butanedi〇1_2 3). The initial content of xiguol in this mouthpiece is not particularly limited, and can be determined based on the solubility of the compound recorded in the precursor 200540885. For example, the mixture may contain a specific amount of multiple Alcohol, so that the content of the nickel precursor compound is about 0.001 to 0.5 moles. To promote the nickel precursor compound to become gold, the method of the present invention includes heating the scale precursor compound. A mixture of fresh alcohols. Here, "heating" refers to raising the temperature of a mixture containing a nickel precursor compound and neoalcohol to a temperature exceeding room temperature, particularly a temperature exceeding about as much as it is. In order to be more effective Promote reduction, the heating temperature is preferably at least about 45 Φ, § The more the heating temperature is riding, The rate will be faster. However, when the -H degree is exceeded, the county's financial affairs will increase in financial bribery. Moreover, V may cause reactants ㈣. In this regard, the heating temperature may be about 10 ° C or lower. In step (i) of the present invention, the composition of the mixture may change with time. Initially, the mixture contains a t-complex and a polyhydric alcohol. During the reduction of the nickel precursor compound to a nickel powder of the FCC phase, the mixture may Firstly, it contains both the pre-recording material σ and the FCC metal extraction age. If the antimony precursor compound other than the hydroxide (nidde ydn_e) ^ is used, some of the precursor compounds will be converted into nickel hydroxide, and then Reduction to Kam powder. The remaining recording precursor compounds can be reduced to metal impurities without undergoing the first conversion to the hydroxide step. T 'After the -like time has elapsed, substantially all of the nickel precursor compounds are still "" Metal powder. As for the length of the heating section, hemp depends on the heating temperature. 12 200540885 The average person familiar with this technical field can easily know the heating time, so the heating time is not the practice of the present invention. Important factors: After heating the mixture in step (a), proceed to step (b) to convert the metal nickel powder from the FCC phase to the HCP phase. In the step), the mixture that has undergone = ⑻- Heating. In step (b), 'If the temperature of the heating mixture is too low, the phase transfer of the powder from the face-centered cubic crystal structure to the hexagonal closest-packed crystal structure will be hindered. If the heating temperature is too high,' the phase transfer rate It may no longer increase. And the alcohol in the mixture may also be decomposed by heating. Therefore, the step_heating temperature may be in the range of about 380 ° C. In one embodiment of the present invention, a The airtight reaction tank of the reflux cooling (reflux 001mg) device, at this time, it is preferable to set the heating temperature in step (b) to be close to the Buddha's axis (p) of the polyol. If the temperature of addition is much lower than that of the polyol, the phase transfer of the powder may not be complete. On the other hand, if the heating temperature is much higher than that of the polyol shaft, there is a problem with the age of the reaction tank. Therefore, the step of the present invention _: temperature ^ perimeter _ polyol _ dot high silk. She Yongqi will heat the mixture of the step mixture to the temperature of the multivariate temperature. In step (b), if the time for heating the mixture for phase transfer is too short, the phase transfer of the powdered FCC to HCP may not be too long, and it may produce nickel ... Come * ❿ And perhaps relying on the necessary heating in the complete shift. 13 200540885 Therefore, the time for heating the mixture for phase transfer in step (b) may be at least about 10 minutes to about 24 k. Also, the phase transfer can be continued for a sufficient period of time, so that substantially all of the FCC phase_powder is converted into Hcp phase_powder. The phase transition time of a specific reaction H can be easily determined by measurement. When the phase transfer is completed, the nickel powder of the HCP phase is separated from the mixture by the general cleaning and drying methods used to prepare the nickel powder. The HCP phase nickel powder prepared according to the method of the present invention is non-magnetic. The nickel powder ' made by the method of the present invention may typically contain at least about 1 plus% of HCp nickel powder. According to another embodiment of the present invention, the mixture in step (a) may further include an organic base, an organic base, or a mixture of the two. It is known from experiments that the nickel precursor compound has an acid value φΗ) of 9 to Π, and the valley is easily reduced to metallic nickel. The organic test is mainly used to adjust the acid test value of the mixture to an appropriate value. The inorganic base may be a hydroxide of an alkali metal, such as NaOH and KOH. Examples of organic tests include tetramethylammonium hydroxide (TMAH), tetraethylammonium hydroxide (TEAH), tetrabutylammonium hydroxide (TBAH), and tetrapropylammonium hydroxide (TBAH) tetrapropylammonium hydroxide (TPAH), benzyltrimethylammonium hydroxide, dimethyldiethylammonium hydroxide, ethyltrimethylammonium hydroxide, osmium oxide Butyl tank 200540885 (tetrabutylphosphonium hydroxide), trimethylamine (TMA), diethylamine (DEA), and ethanolamine, and the aforementioned organic bases can be used alone or in combination. The content of the base of the present invention in the mixture is not particularly limited. For example, the test may be a specific content such that the initial acid test value of the mixture reaches about 9 or more, more preferably 10 or more, to reach a better reaction state. As a more illustrative example, if the mixture contains a mole nickel precursor compound, the initial base content of the mixture may be in the range of about 1 to 10 moles. According to another embodiment of the present invention, the mixture in step (i) may further include a nucleation agent. The nucleating agent is used to precipitate the reduced metallic nickel powder to form a more uniform particle size. Nucleating agents can be potassium chloroplatinate (K2ptCl4), chloroplatinate (6), dichloride! Bar (pdcy, or silver nitrate (AgNO3). The content of the nucleating agent in the mixture is not particularly limited. For example, if there is 1 mole of nickel precursor compound in the mixture, the content of the nucleating agent in the mixture may be About 1 / 1,000,000 to 2 / 1,000 moles. In general, the content of the nucleating agent in the mixture is about 0.1% of the nickel precursor compound. The present invention will be described more clearly below by way of example. However, the following examples are for illustration only, and the present invention should not be limited thereto. EXAMPLES Example 1 (TEG + TMAH) 15 200540885 In 250 milliliters (ml) of triethylene glycol (TEG), dissolved 90 · 6 Grams (g) of tetrahydrofuran (TMAH) hydroxide 'to prepare a first solution. In 250 ml of triethylene glycol, 40 g of Ni (CH3COO) 2 · 4H20 (nickel acetate tetrahydrate) was dissolved, To prepare a second solution. Using chloroplatinic acid bell as a nucleating agent, dissolve 0.0064 g of potassium chloroplatinate (K2PtCl4) in 2 ml of ethylene glycol (EG), To prepare a third solution. The first solution, the second solution, and the third solution are placed in a reflux cooler The mixture was stirred in a reactor using a heating mantle equipped with a magnetic stir bar at 190 ° C for 10 minutes to produce FCC metal nickel powder. At this time, take The resulting FCC nickel metal powder sample was centrifuged and then washed with ethanol. The FCC nickel metal powder sample thus obtained was dried in a vacuum oven at 25 ° C.

night. Then, the saturation magnetization of the FCC sample was measured with MODEL4VSM 30 kOe (DMS Co., Ltd.) to obtain 24.0 emu / g. Then the mixture was heated in the original reactor at 220 ° C and the nickel powder was sampled over time. A sample of the nickel powder was centrifuged and then washed with ethanol. The nickel powder sample thus obtained was dried overnight in a vacuum oven at 25 ° C. The X'PERT_MPD system (Philips Co., Ltd.) was used at 10 ° to 90 °. The X-ray diffraction (XRD) analysis of the sample was performed at an angle of 90 °, and the relationship between the results obtained and time is shown in Figure 1. As shown in Figure 1, all samples taken at the time point of the 1-24 hour time course were transferred to the HCP phase. And, the saturation magnetization of each sample was measured to obtain 0.030 emu / g (for 1 hour), 0.028 emu / g (for 2 hours, 16 200540885 hours), 0.027 emu / g (for 3 hours), and 0.020 emu / g (Duration 4 hours), 0.019 emu / g (duration 5 hours), 0.019 emu / g (duration 6 hours), 0.018 emu / g (duration 7 hours), 0.018 emu / g (duration 8 hours), 0.019 emu / g (duration 9 hours), 0.018 emu / g (duration 10 hours), 0.018 emu / g (duration 24 hours). That is, when the crystalline phase of the nickel powder is transferred from the FCC to HCP, the saturation magnetization of the nickel powder is reduced to about 1/1200 of the FCC. The particles of the FCC and HCP nickel powders prepared from Example 1 had an average particle diameter of about 180 nm and were spherical. Example 2 (DEG + TMAH) 90.6 g of tetramethylammonium hydroxide (TMAH) was dissolved in 250 ml of ethylene glycol (DEG) to prepare a first solution. 30 g of Ni (CH3COO) 2. 4H20 was dissolved in 250 ml of DEG to prepare a second solution. Using potassium chloroplatinate as a nucleation agent, 0.0249 g of potassium chloroplatinate was dissolved in 2 ml of ethylene glycol to prepare a third solution. The first solution, the second solution, and the third solution were placed in a reactor equipped with a reflux cooler and stirred. The obtained mixture was heated at 190 ° C for 40 minutes using a heating bag equipped with a magnetic stir bar to produce FCC metal nickel powder. The obtained FCC metal nickel powder was centrifuged and then washed with ethanol. The iFCC metallic nickel powder thus obtained was dried in a vacuum oven at 25 ° C overnight. The saturation magnetization of the FCC nickel powder was measured to be 24.2 emu / g. Then, the mixture was heated in the original reactor at 22 ° C, and the nickel powder was sampled over time. A sample of the nickel powder was centrifuged and then washed with ethanol. The nickel powder sample thus obtained was dried overnight in a vacuum oven at 25 ° C. At 丨 〇. To 90. The X-ray diffraction (XRD) analysis of the sample was performed at an angle of 90 °, and the relationship between the obtained results and time is shown in FIG. 2. The nickel powder fraction with HCP crystal structure in the sample was 10 plus 0 / 〇 (for 1 hour), IS wt% (for 2 hours), 29 wt% (for 3 hours), and 35 wt% (for 4 hours). ). The saturation magnetization values of the samples were 23.4 emu / g (for 1 hour), 22.8 emu / g (for 2 hours), η ·? Emu / g (for 3 hours), and 21〇emu / g (for 4 hours) ). These values are lower than the saturation magnetization value of the above FCC nickel powder (24.2 _ emu / g). The particles of the FCC and HCP nickel powder prepared from Example 2 have an average particle diameter of about 220 nm and are spherical. Example 3 (DEG + TMAH) A solution containing 10 g of a 2.5 M sodium hydroxide aqueous solution, 0.054 g of potassium chloroplatinate, 500 ml of ethylene glycol, and 30 g of Ni (CH3C00) 2. 4Η20 The mixture was placed in a reactor equipped with a reflux cooler and stirred. ® The mixture was heated in a reactor at 190 ° C for 30 minutes to produce FCC metal nickel powder. Then, the mixture in the same reactor was heated at 190 ° C for 24 hours to perform phase transfer of nickel powder. Then, the nickel powder was centrifuged and washed with ethanol. The nickel powder thus obtained was dried in a vacuum oven at 25 ° C overnight. Then, X-ray diffraction (XRD) analysis was performed on the nickel powder thus obtained, and the results are shown in Fig. 3. The HCP fraction of the nickel powder was 100 wt%. The saturation magnetic value of the nickel powder was measured. 2005 2005885 The chemical value was 0.03 emu / g. Observation with a scanning electron microscope (SEM) revealed that the particles of the nickel powder had an average particle diameter of approximately a leg and were spherical. Example 4 (EG) A mixture containing 0.054 g of chlorourinic acid, 500 ml of ethylene glycol, and 30 g of Ni (CH3COO) 2. 4H2O was placed in a reflux cooler. Reactor and stir. _ The mixture was heated in a reactor at 190 C for 1 hour to produce pec metal nickel powder. XRD analysis was performed on this FCC nickel powder, and the results are shown in FIG. 4. The FCC fraction of the nickel powder was 100 wt ° /. . The saturation magnetization value of this FCC nickel powder was measured to be 24.5 emu / g. Next, the mixture was heated in the original reactor at 1900c for 24 hours to perform phase transfer of the nickel powder. Then, the powder was centrifuged and washed with ethanol. The nickel powder thus obtained was dried in a vacuum oven at 25 ° C overnight. Clicking and then 'performing a wire diffraction diffraction (XR0) analysis on the nickel powder thus obtained, the results are not as shown in FIG. 5. The HCP score of powdering was %%%. The saturation magnetization of the nickel powder was measured at 18.5 emu / g. Observation by SEM showed that the recorded particles had an average particle diameter of about 3 gland and were hemispherical. It can be clearly understood from the above that according to the method of the present invention, a non-magnetic nickel powder having a hexagonal close-packed crystal structure can be easily produced. 19 200540885 The above is only a preferred embodiment of the present invention, and any equivalent modification made in accordance with the scope of patents claimed in the present invention shall fall within the scope of the temple of the present invention. [Brief Description of the Drawings] FIG. 1 is a result of X-ray diffraction (and milk) analysis of a metallic nickel powder according to an embodiment of the present invention. FIG. 2 is a result of X-ray diffraction (XRD) analysis of a metallic nickel powder according to another embodiment of the present invention. Fig. 3 is an analysis result of a metallic nickel powder according to another embodiment of the present invention. Fig. 4 is an XRD analysis result of an intermediate (FCC metallic nickel powder) according to another embodiment of the present invention. Fig. 5 is an XRD analysis result of the final product of the metal nickel powder containing HCP obtained in the example of Fig. 4. [Description of main component symbols] There are no component symbols in the drawings of this case.

Claims (1)

  1. 200540885 10. Scope of patent application: 1. A method for manufacturing non-magnetic nickel powder, including the following steps: (a) heating a mixture containing a nickel precursor compound and a polyol ( polyol) to reduce the nickel precursor compound to a metal-nickel powder having a face-centered cubic structure, and (b) a metal structure; and (b) the mixture obtained in the heating step, to at least A portion of the nickel powder having a face-centered cubic crystal structure is converted into a nickel powder having a hexagonal closest packing (I ^ χ ^ 〇η & 1 close packed, HCP) crystal structure. 2. The method according to item 1 of the scope of patent application, wherein the nickel precursor compound is nickel acetate, nickel sulfate, nickel chloride, or a mixture thereof. 3. The method according to item 1 of the scope of patent application, wherein the polyhydric alcohol is ethyleneglycol, diethyleneglycol, triethyleneglycol, tetraethyleneglycol ( tetraethyleneglycol), 1,2-propanediol-1, 2,3-propanediol-1, 3, propanediol-1, butanediol-1, butanediol-1 2), 1,3-butanediol-1,3, 1,4-butanediol-1,4, 2,3-butanediol 21 200540885 (butanediol_2,3), or a mixture thereof. 4. The method according to item 1 of the scope of patent application, wherein the mixture in step (a) further comprises an organic base, an inorganic base, or a mixture thereof. 5. The method as described in item 4 of the scope of patent application, wherein the organic base is tetramethylammonium hydroxide (TMAH), tetraethylammonium hydroxide (TEAH), tetrabutyl hydroxide Tetrabutylammoniumhydroxide (TBAH), tetrapiOpylammonium hydroxide (TPAH), benzyltrimethylammonium hydroxide, dimethyldiethylammoniumhydroxide, ethyl hydroxide ^ 1 > 4 notes 11 ^ 11} such as 111111〇11 丨 1111111) ^ 〇 parent 丨 (1), tetrabutylphosphonium hydroxide, trimethylamine (TMA), One or more selected from the group consisting of diethylamine (DEA) and ethanolamine (ethan () lamine). 6. The method according to item 1 of the scope of patent application, wherein the mixture in step (a) further comprises a nucleation agent. 22 200540885 7. The method described in item No. of the patent application range, which makes this step not to be performed in the temperature range of 45 to 350 C. 8. The method according to item 1 of the stated patent range, wherein the step is performed in a temperature range of ⑽ to 380 ° C. 9. The method according to item i of the declared patent range, wherein the step is performed within a temperature range of ± 5 ° C of the boiling point of the polyol. φ 1 0. The method as described in item 1 of the patent application range, wherein the step (b) is performed at a temperature range in which the polyalcohol is boiling. 11. The method described in the scope of application for patent No. lJf • Interviewer ^, wherein, in step (b), the heating is performed for 10 minutes to 24 hours. ) '11 、 Schematic ·· 23
TW93115905A 2004-06-02 2004-06-02 Method for preparing non-magnetic nickel powders TWI234789B (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
TWI557411B (en) * 2014-06-25 2016-11-11 村田製作所股份有限公司 Method of identifying direction of multilayer ceramic capacitor, apparatus identifying direction of multilayer ceramic capacitor, and method of manufacturing multilayer ceramic capacitor
US9714921B2 (en) 2014-06-25 2017-07-25 Murata Manufacturing Co., Ltd. Method of identifying direction of multilayer ceramic capacitor, apparatus identifying direction of multilayer ceramic capacitor, and method of manufacturing multilayer ceramic capacitor

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
TWI557411B (en) * 2014-06-25 2016-11-11 村田製作所股份有限公司 Method of identifying direction of multilayer ceramic capacitor, apparatus identifying direction of multilayer ceramic capacitor, and method of manufacturing multilayer ceramic capacitor
US9714921B2 (en) 2014-06-25 2017-07-25 Murata Manufacturing Co., Ltd. Method of identifying direction of multilayer ceramic capacitor, apparatus identifying direction of multilayer ceramic capacitor, and method of manufacturing multilayer ceramic capacitor

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