JPS6291422A - Production of fine tantalum oxide particle - Google Patents

Production of fine tantalum oxide particle

Info

Publication number
JPS6291422A
JPS6291422A JP23259385A JP23259385A JPS6291422A JP S6291422 A JPS6291422 A JP S6291422A JP 23259385 A JP23259385 A JP 23259385A JP 23259385 A JP23259385 A JP 23259385A JP S6291422 A JPS6291422 A JP S6291422A
Authority
JP
Japan
Prior art keywords
tantalum
tantalum oxide
particles
reaction
water
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
JP23259385A
Other languages
Japanese (ja)
Other versions
JPH0610088B2 (en
Inventor
Masanori Kato
誠軌 加藤
Koreyasu Mizutani
水谷 惟恭
Nobuo Ishizawa
石澤 伸夫
Nobuo Kieda
暢夫 木枝
Masaaki Mitarai
征明 御手洗
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Sumitomo Metal Mining Co Ltd
Tokyo Institute of Technology NUC
Original Assignee
Sumitomo Metal Mining Co Ltd
Tokyo Institute of Technology NUC
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Sumitomo Metal Mining Co Ltd, Tokyo Institute of Technology NUC filed Critical Sumitomo Metal Mining Co Ltd
Priority to JP23259385A priority Critical patent/JPH0610088B2/en
Publication of JPS6291422A publication Critical patent/JPS6291422A/en
Publication of JPH0610088B2 publication Critical patent/JPH0610088B2/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Abstract

PURPOSE:To obtain the titled fine Ta2O5 particles having high sphericity and a narrow distribution of particle diameters by adding an aq. alcoholic soln. to the alcoholic soln. of a tantalum alkoxide under controlled conditions and hydrolyzing the tantalum alkoxide. CONSTITUTION:The aq. alcoholic soln. is added to the alcoholic soln. of the tantalum alkoxide and the tantalum alkoxide is hydrolyzed to produce the fine Ta2O5 particles. In this case, the concn. of the tantalum alkoxide in the reaction soln. is regulated to <=0.2mol/l, the amt. of water is controlled to the amt. 0.7-1.3 times the equivalent amt. necessary for the hydrolysis of the tantalum alkoxide, the alcohol 0.5 times the total amt. of the reaction soln. is added immediately after the aq. alcoholic soln. is added, then the reaction soln. is agitated to form and grow fine Ta2O5 particles. Consequently, fine Ta2O5 particles having high sphericity and a narrow distribution of particle diameters can be obtained.

Description

【発明の詳細な説明】 〔産業上の利用分野〕 本発明は、酸化タンタル微粒子の製造方法に関し、特に
、真球度が高く粒径分布の狭い酸化タンタル微粒子の製
造方法に関する。
DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for producing tantalum oxide fine particles, and particularly to a method for producing tantalum oxide fine particles having high sphericity and a narrow particle size distribution.

〔従来の技術〕[Conventional technology]

近年、金属酸化物微粒子の製造方法として、金属アルコ
キシドの加水分解反応を制御することにより1敗粒子を
製造する方法が、(alアルコキシドが常温で容易に加
水分解して酸化物(通常、水和物の状態)を生成するこ
と、(bl加水分解の条件を比較的制御し易いこと、(
Cl純度の高い原料アルコキシドを得やすいこと、(d
ii純物や陰イオン辱が生成物に混入するおそれがない
こと、などの利点を有するため注目され、酸化ケイ素(
SiO□)および酸化チタン(TiO□)に関してかか
る方法による製造の試みが行われている。
In recent years, as a method for producing metal oxide fine particles, there has been a method of producing one-piece particles by controlling the hydrolysis reaction of metal alkoxide (alkoxide is easily hydrolyzed at room temperature to form oxide (usually hydrated). The conditions of bl hydrolysis are relatively easy to control;
Easy to obtain raw material alkoxide with high Cl purity (d
ii) Silicon oxide (
Attempts have been made to manufacture SiO□ and titanium oxide (TiO□) using such a method.

しかしながら酸化タンタル粒子に関しては、上記のタン
タルアルコキシドの加水分解を利用する製法を含め、単
分散性の高い球形でサブミクロンオーダーの微粒子の製
法は、従来まったく知られていない。
However, with regard to tantalum oxide particles, there has been no known method for producing spherical, submicron-order fine particles with high monodispersity, including the above-mentioned production method utilizing hydrolysis of tantalum alkoxide.

〔発明が解決しようとする問題点〕[Problem that the invention seeks to solve]

本発明の目的ば、単針11シ性の高い球形でリーブミク
ロンオーダーの酸化タンタル微粒子の製法が従来確立さ
れていない問題に鑑の、かかる製法を11?供すること
にある。
The purpose of the present invention is to solve the problem in which a manufacturing method for tantalum oxide fine particles having a spherical shape on the order of micrometers with a single needle and high flexiability has not been established. It is about providing.

〔問題点を解決するための手段〕[Means for solving problems]

本発明は、11;1記の問題点を解決する手段とし−(
、メンタ11フ月仁+4−シ1のアルご1−ル?容液に
水のアルコール溶液を添加11シ、タンタル了ル″1キ
シ1′の加水分解反応にlり酸化タンタル微粒子を製造
する方法であって、 反応開始時における反応溶液中のタンタルアルコキシド
の?alkを(1,2n+off以−ドに、水の璽をタ
ンタルアルコキシドの加水分解に要する力計の0.7〜
1.3倍Vに制御Iシ、 水のアルコール溶液を添加した直後に反応溶液全量の0
.5倍量以上のアルコールを協力11シ、次いで反応溶
ン夜を攪拌し、酸化タンタル倣i◇了を生成、成I4さ
−lることからなる酸化タンタル微粒子の製造方法を堤
供するものである。
The present invention is a means for solving the problems described in 11; 1-(
, Menta 11 Futsuki Jin + 4-Shi 1 Algo 1-R? A method for producing fine particles of tantalum oxide by adding an alcoholic solution of water to a solution, and then hydrolyzing tantalum "1x1". alk (from 1,2n+off), and water from 0.7 to 0.7 on the force meter required for hydrolysis of tantalum alkoxide.
Control I to 1.3 times V, and immediately after adding the alcoholic solution of water, reduce the total amount of reaction solution to 0.
.. The present invention provides a method for producing tantalum oxide fine particles, which comprises adding more than 5 times the amount of alcohol, and then stirring the reaction solution to form tantalum oxide imitators. .

本発明に、l、ると、生成した酸化タンタル1敢粒子同
士の凝集が効果的に防lトされる一方、それらの粒子成
長が良好に促進される結果、真球度が極めて高く、粒径
分布の狭いタンタル酸化物微Jq子が得られる。
In the present invention, the agglomeration of the generated tantalum oxide particles is effectively prevented, while the growth of these particles is favorably promoted, resulting in extremely high sphericity and grains. Fine tantalum oxide Jq particles with a narrow diameter distribution are obtained.

なお、ここで得られる酸化タンタルは一般に水和物であ
るが、本明細書では、単に[酸化タンタル[と称する。
Although the tantalum oxide obtained here is generally a hydrate, it is simply referred to as tantalum oxide in this specification.

本発明において用いられるタンクルアルコキシ1として
は、例えば、タンタルメトキシl′、タンタルエトキシ
ド、タンクルプロポキシド、タンタルシト−)−シト等
が挙げられる。
Examples of the tantalum alkoxy 1 used in the present invention include tantalum methoxy 1', tantalum ethoxide, tantalum propoxide, tantalum cyto-)-cyto, and the like.

本発明の方法では、原料であるタンタルアルコキシドお
よび水のアルニ1−ルン容ン夜が使用される。
In the method of the present invention, raw materials tantalum alkoxide and water are used.

こごで用いられるアルコールは、タンタルアルコキシド
および水の良溶媒であり、具体例としては、メタノール
、エタノール、プロパツール等を挙げることができる。
The alcohol used here is a good solvent for tantalum alkoxide and water, and specific examples include methanol, ethanol, propatool, and the like.

タンタルアルコキシド アルコール溶液を添加して加水分解反応を開始させるが
、この反応開始時における反応溶液中のタンタルアルコ
−1−シlの4度を0. 2 mol/ (l I’d
下、好ましくは0.08〜0. 2 mol/ 7!、
特に好ましくは約0、1 mol/βに制ii1’ll
するとともに、反応溶液中の水の量を、加水分解反応に
必要な力計(化学量論尾)の0.7〜1.3イ合M.’
)fましくは当−の0.9〜1.3倍量、特に好ましく
はほぼ当量に制御する必要がある。反応開始時における
反応溶液中のタンクルアルコキ丸7眉度が0. 2 m
ol/ 1を超えると、得られる酸化タンタル微粒子の
粒度分布が広くなり易い。また、水の鼠が多過ぎると、
得られる粒子の粒径の均一性が低下し7、粒径分布が広
がる。また、水の量が少な過ぎると酸化タンタルのコl
’lイ1粒子の析出に時間がかかり好ましくない。
The hydrolysis reaction is started by adding a tantalum alkoxide alcohol solution, and the 4 degrees of tantalum alcohol-1-sil in the reaction solution at the start of the reaction is 0. 2 mol/ (l I'd
Below, preferably 0.08 to 0. 2 mol/7! ,
Particularly preferably limited to about 0.1 mol/βii1'll
At the same time, the amount of water in the reaction solution was adjusted to 0.7 to 1.3 iM on a force meter (stoichiometric tail) necessary for the hydrolysis reaction. '
) It is necessary to control the amount preferably to 0.9 to 1.3 times the equivalent amount, particularly preferably approximately the same amount. At the start of the reaction, the degree of tankle alcohol in the reaction solution is 0. 2 m
When it exceeds ol/1, the particle size distribution of the obtained tantalum oxide fine particles tends to become wide. Also, if there are too many water rats,
The uniformity of the particle size of the resulting particles is reduced 7 and the particle size distribution is broadened. Also, if the amount of water is too small, tantalum oxide
It is undesirable that it takes a long time to precipitate one particle.

例えば、タンクルペンタアルコキシドを原車−1として
用いる場合、加水分解反応は、下記反応式:Ta(OR
)s ’I’5 1120 −”Ta(Oll)s +
5 Roll(但し、12G11−メルートル基) に従うと嶌えられ、、二の場合タンタルアルコキシド1
molに対する水の反応当量は5molであるから、本
発明によると水は3.5〜6.5mol の範囲の量で
添加される。
For example, when tank penta alkoxide is used as the base vehicle-1, the hydrolysis reaction is performed using the following reaction formula: Ta(OR
)s 'I'5 1120 −”Ta(Oll)s +
5 Roll (however, 12G11-Merutol group) is followed, and in the case of 2, tantalum alkoxide 1
Since the reaction equivalent of water per mol is 5 mol, according to the invention water is added in an amount ranging from 3.5 to 6.5 mol.

反応開始時の反応溶液中のタンタルアルコキシドの濃度
および水の川の制御は、タンタルアルコキラ/(−のア
ルコール溶液の濃度および量、並びに添加される水のア
ルコール溶液の濃度および量を調節することで、容易に
行なうことができる。
The concentration of tantalum alkoxide in the reaction solution and the flow of water at the start of the reaction can be controlled by adjusting the concentration and amount of alcoholic solution of tantalum alkoxide/(-, and the concentration and amount of alcoholic solution of water added. And it can be done easily.

上述のように水のアルコール溶液を添加した直後にアル
コールを添加し反応溶液を希釈する。水のアルコール溶
液の添加およびアルコールの添加は、一般に反応溶液の
攪拌下、室温で行なうが、アルコールの添加は水のアル
コール溶液の添加直後、ずなわら、水のアルコール溶液
の添加後数十秒以内に行なう必要がある。アルコールの
添j311が遅れると、生成した酸化タンタル微粒子間
の凝集が起り易くなり、真球状に形状が揃ったi戚粒子
を得ることば困難である。
Immediately after adding the alcoholic solution of water as described above, alcohol is added to dilute the reaction solution. The addition of the alcoholic solution of water and the addition of the alcohol are generally carried out at room temperature while stirring the reaction solution, but the addition of the alcohol is carried out immediately after the addition of the alcoholic solution of water, and usually several tens of seconds after the addition of the alcoholic solution of water. It needs to be done within. If addition of alcohol is delayed, aggregation of the generated tantalum oxide fine particles is likely to occur, making it difficult to obtain particles having a perfectly spherical shape.

したがって、アルコールを添加するまでの時間を精密に
制御することによって核の生成数を制御し、そ相らの核
だけを成長させることによって任意の粒径の酸化タンタ
ル粒子を製造することが可能である。
Therefore, it is possible to manufacture tantalum oxide particles of any particle size by controlling the number of nuclei generated by precisely controlling the time until alcohol is added, and by growing only those nuclei. be.

アルコールの添加m 4.1、l容冶全体の0.5倍尾
以上、好ましく 4.1i O,8〜1.5倍−である
ことが必要である。このアル’:i−/しの添J用によ
って後続の1貨化タンタルの核ノ1成および4成した微
粒子同上の凝集が抑制され、得らJする11″l−J’
! t;I真球状に形状が揃い、かつ比較的粒径分布の
狭いものとなる。アルコールの添加量が0.5倍耐未満
であると、得られる粒子の凝集を十分に抑制できず、ま
た多分散性の高いものとなる。なお、このアルコール添
加量が多過ぎると、反応溶液中のTa(0’H)sの濃
度が低くなることによ、て酸化タンレルの収率力5低下
したり、粒成長に要する時間が長< lrる、など製造
上の不利が生じる。なお、添加するアルコールは、溶液
を稀釈するためのものであり、1−配力]1水分解に関
して例示のものを用いることができるが、加水分解時に
用いたアル:1−ルと異なるものでも差し支えない。
It is necessary that the amount of alcohol added is 0.5 times or more, preferably 4.1i O, 8 to 1.5 times the total amount of alcohol added. By adding this Al':i-/Shinoto, the subsequent agglomeration of the fine particles of 1 and 4 formed tantalum atoms is suppressed, and the resulting agglomeration of 11"l-J'
! t;I The particles are perfectly spherical in shape and have a relatively narrow particle size distribution. If the amount of alcohol added is less than 0.5 times, the agglomeration of the resulting particles cannot be sufficiently suppressed and the polydispersity becomes high. Note that if the amount of alcohol added is too large, the concentration of Ta(0'H)s in the reaction solution will decrease, resulting in a decrease in the yield of Tanrel oxide and a longer time required for grain growth. There are manufacturing disadvantages such as <lrru. The alcohol to be added is for diluting the solution, and the alcohols exemplified for 1-hydrolysis can be used, but alcohols different from the alcohol used during hydrolysis may also be used. No problem.

前記アルコールの添加後、)容液を攪拌しながら、反応
を行なわ−1る。加水分解反応の進行により酸化タンタ
ルコロイドが生成し、反応溶液が白濁する。その後必要
に応じた時間反応を進行せしめることにより酸化タンタ
ル粒子を所望の粒径に成長させる。通常、アルコール添
加後20〜40程度度の撹拌により1.0〜1.5μm
程度の粒径を有する酸化タンタル微粒子を得ることがで
きる。
After the addition of the alcohol, the reaction is carried out while stirring the solution. As the hydrolysis reaction progresses, tantalum oxide colloid is produced, and the reaction solution becomes cloudy. Thereafter, tantalum oxide particles are grown to a desired particle size by allowing the reaction to proceed for a time period as required. Usually, 1.0 to 1.5 μm by stirring at about 20 to 40 degrees after adding alcohol.
It is possible to obtain tantalum oxide fine particles having a particle size of approximately

次いで所望の粒径に成長した酸化タンタル微粒子を遠心
分離によって回収し、これを適当な溶媒を用いて分散処
理して乾燥することにより酸化タンタル微粒子を得るこ
とができる。
Next, tantalum oxide fine particles that have grown to a desired particle size are collected by centrifugation, dispersed using an appropriate solvent, and dried to obtain tantalum oxide fine particles.

〔実施例〕〔Example〕

?農度0: I 25 mol/ (lでタンクルペン
タエトキシドTa(OC21js) sを含むn−ブタ
ノール−エタノール混合溶液40m7!に、濃度2.5
mol/βで水を含むn−ブタノール−エタノール混合
溶液10mj!を撹拌F室温で添加し、その30秒後に
n−ブタノール50mnを添加し、超音波分散機(29
kllz)による反応?8液の撹拌を続けた。約30分
後、反応溶液の白濁化が観測され、合計90分間の撹拌
を行なった後、生成した酸化タンタル徹粒子を遠心分離
機により固液分則し、60 ”cで乾燥させた。
? Agricultural degree 0: I 25 mol/(l) To 40 m7 of n-butanol-ethanol mixed solution containing tank pentaethoxide Ta (OC21js) s, concentration 2.5
10 mj of n-butanol-ethanol mixed solution containing water in mol/β! was added at room temperature while stirring, 30 seconds later, 50 mL of n-butanol was added, and an ultrasonic dispersion machine (29 mm) was added.
reaction by kllz)? Stirring of the 8 liquid was continued. After about 30 minutes, the reaction solution was observed to become cloudy, and after stirring for a total of 90 minutes, the produced tantalum oxide particles were separated into solid and liquid using a centrifuge and dried at 60''c.

得られた酸化タンタル微粒子について以下の測定を行な
った。
The following measurements were performed on the obtained tantalum oxide fine particles.

得られた酸化タンタル微粒子は、第1図に示す走査型電
子顕微鏡写真から、真球状に形状が揃った微粒子で、粒
径分布が極めて狭いものであることが分かった。
The obtained tantalum oxide fine particles were found to be perfectly spherical fine particles with an extremely narrow particle size distribution from the scanning electron micrograph shown in FIG.

さらにまた、得られた微粒子粉末は非晶質に特有のブロ
ードなX線回折図形を示した。これを示差熱天秤(DT
A −TG)で分析した結果、200 ”cまでに水和
水の脱離を示す吸熱が起こり、740 ’c付近で結晶
化に伴なう発熱ピークが観測された。
Furthermore, the obtained fine particle powder exhibited a broad X-ray diffraction pattern characteristic of an amorphous material. This was measured using a differential thermal balance (DT
As a result of analysis with A-TG), an endotherm indicating desorption of hydration water occurred by 200'c, and an exothermic peak associated with crystallization was observed around 740'c.

〔発明の効果〕〔Effect of the invention〕

本発明によれば、真球度が極めて高く、粒径分布が比較
的狭い酸化タンタル微粒子を得ることができる。この酸
化タンタルは、非晶質の水和物であるが、加熱に3L、
り水和水を除くことができ、740℃程度まで加熱すれ
ば結晶化する。本発明による酸化チタン粉末は、粒径が
比較的揃った真球状微粒子であるため、焼結セラミック
スの原料粉末としても好適である。また、エレクトロニ
クス材料、顔lit、塗料、化粧品、宝石等、種々の用
途への適用も期待される。
According to the present invention, tantalum oxide fine particles having extremely high sphericity and a relatively narrow particle size distribution can be obtained. This tantalum oxide is an amorphous hydrate, but it takes 3L to heat up.
The hydration water can be removed and crystallization occurs when heated to about 740°C. Since the titanium oxide powder according to the present invention is truly spherical fine particles with relatively uniform particle sizes, it is also suitable as a raw material powder for sintered ceramics. It is also expected to be applied to various uses such as electronic materials, face lits, paints, cosmetics, and jewelry.

【図面の簡単な説明】[Brief explanation of drawings]

第1図は本発明の実施例により得られた酸化タンタル微
粒子の走査型電子顕微鏡写真である。
FIG. 1 is a scanning electron micrograph of tantalum oxide fine particles obtained in an example of the present invention.

Claims (1)

【特許請求の範囲】 タンタルアルコキシドのアルコール溶液に水のアルコー
ル溶液を添加し、タンタルアルコキシドの加水分解反応
により酸化タンタル微粒子を製造する方法であって、 反応開始時における反応溶液中のタンタルアルコキシド
の濃度を0.2mol以下に、水の量をタンタルアルコ
キシドの加水分解に要する当量の0.7〜1.3倍量に
制御し、 水のアルコール溶液を添加した直後に反応溶液全量の0
.5倍量以上のアルコールを添加し、次いで反応溶液を
攪拌し、酸化タンタル微粒子を生成、成長させることか
らなる酸化タンタル微粒子の製造方法。
[Claims] A method for producing tantalum oxide fine particles by a hydrolysis reaction of tantalum alkoxide by adding an alcoholic solution of water to an alcoholic solution of tantalum alkoxide, the method comprising: increasing the concentration of tantalum alkoxide in the reaction solution at the start of the reaction; The amount of water is controlled to be 0.7 to 1.3 times the equivalent amount required for hydrolysis of tantalum alkoxide, and immediately after adding the alcoholic solution of water, 0.2 mol or less of the total amount of the reaction solution is added.
.. A method for producing tantalum oxide fine particles, which comprises adding 5 times or more of alcohol and then stirring the reaction solution to generate and grow tantalum oxide fine particles.
JP23259385A 1985-10-18 1985-10-18 Method for producing fine particles of tantalum oxide Expired - Lifetime JPH0610088B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP23259385A JPH0610088B2 (en) 1985-10-18 1985-10-18 Method for producing fine particles of tantalum oxide

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP23259385A JPH0610088B2 (en) 1985-10-18 1985-10-18 Method for producing fine particles of tantalum oxide

Publications (2)

Publication Number Publication Date
JPS6291422A true JPS6291422A (en) 1987-04-25
JPH0610088B2 JPH0610088B2 (en) 1994-02-09

Family

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Family Applications (1)

Application Number Title Priority Date Filing Date
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Country Status (1)

Country Link
JP (1) JPH0610088B2 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0842990A3 (en) * 1996-11-14 2000-02-23 Degussa-Hüls Aktiengesellschaft Spherical colour pigments, process for their preparation and their use
JP2007277091A (en) * 2007-07-27 2007-10-25 Dowa Holdings Co Ltd Tantalum oxide and method of manufacturing the same

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
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JP2007277091A (en) * 2007-07-27 2007-10-25 Dowa Holdings Co Ltd Tantalum oxide and method of manufacturing the same

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