JPS62241822A - Production of porcelain powder material of dielectric material - Google Patents
Production of porcelain powder material of dielectric materialInfo
- Publication number
- JPS62241822A JPS62241822A JP8744886A JP8744886A JPS62241822A JP S62241822 A JPS62241822 A JP S62241822A JP 8744886 A JP8744886 A JP 8744886A JP 8744886 A JP8744886 A JP 8744886A JP S62241822 A JPS62241822 A JP S62241822A
- Authority
- JP
- Japan
- Prior art keywords
- neodymium
- fine powder
- mixed solution
- barium titanate
- purity
- 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.)
- Pending
Links
- 239000000843 powder Substances 0.000 title claims abstract description 23
- 239000000463 material Substances 0.000 title claims abstract description 11
- 229910052573 porcelain Inorganic materials 0.000 title claims abstract description 6
- 238000004519 manufacturing process Methods 0.000 title claims description 8
- 239000003989 dielectric material Substances 0.000 title abstract description 3
- 229910052779 Neodymium Inorganic materials 0.000 claims abstract description 15
- 229910002113 barium titanate Inorganic materials 0.000 claims abstract description 15
- QEFYFXOXNSNQGX-UHFFFAOYSA-N neodymium atom Chemical compound [Nd] QEFYFXOXNSNQGX-UHFFFAOYSA-N 0.000 claims abstract description 14
- JRPBQTZRNDNNOP-UHFFFAOYSA-N barium titanate Chemical compound [Ba+2].[Ba+2].[O-][Ti]([O-])([O-])[O-] JRPBQTZRNDNNOP-UHFFFAOYSA-N 0.000 claims abstract description 13
- 238000010438 heat treatment Methods 0.000 claims abstract description 10
- 150000004703 alkoxides Chemical class 0.000 claims abstract description 6
- 239000011259 mixed solution Substances 0.000 claims abstract description 6
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims abstract description 5
- 229910052788 barium Inorganic materials 0.000 claims abstract description 5
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 5
- 229910052719 titanium Inorganic materials 0.000 claims abstract description 4
- 239000007858 starting material Substances 0.000 claims description 5
- DSAJWYNOEDNPEQ-UHFFFAOYSA-N barium atom Chemical compound [Ba] DSAJWYNOEDNPEQ-UHFFFAOYSA-N 0.000 claims description 4
- 238000006460 hydrolysis reaction Methods 0.000 claims description 4
- 229910052751 metal Inorganic materials 0.000 claims description 4
- 239000002184 metal Substances 0.000 claims description 4
- 239000010936 titanium Substances 0.000 claims description 4
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 claims description 3
- 230000007062 hydrolysis Effects 0.000 claims description 3
- 238000000034 method Methods 0.000 abstract description 12
- 239000002994 raw material Substances 0.000 abstract description 5
- AYJRCSIUFZENHW-UHFFFAOYSA-L barium carbonate Chemical compound [Ba+2].[O-]C([O-])=O AYJRCSIUFZENHW-UHFFFAOYSA-L 0.000 abstract description 4
- 239000002245 particle Substances 0.000 abstract description 4
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 abstract description 3
- 238000007796 conventional method Methods 0.000 abstract description 3
- PLDDOISOJJCEMH-UHFFFAOYSA-N neodymium oxide Inorganic materials [O-2].[O-2].[O-2].[Nd+3].[Nd+3] PLDDOISOJJCEMH-UHFFFAOYSA-N 0.000 abstract description 3
- 239000010409 thin film Substances 0.000 abstract description 3
- 239000000126 substance Substances 0.000 abstract description 2
- 238000001354 calcination Methods 0.000 abstract 2
- 230000003301 hydrolyzing effect Effects 0.000 abstract 1
- KFZMGEQAYNKOFK-UHFFFAOYSA-N Isopropanol Chemical compound CC(C)O KFZMGEQAYNKOFK-UHFFFAOYSA-N 0.000 description 8
- 239000000203 mixture Substances 0.000 description 7
- UHOVQNZJYSORNB-UHFFFAOYSA-N Benzene Chemical compound C1=CC=CC=C1 UHOVQNZJYSORNB-UHFFFAOYSA-N 0.000 description 6
- 239000000919 ceramic Substances 0.000 description 4
- 238000003746 solid phase reaction Methods 0.000 description 4
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 3
- LRHPLDYGYMQRHN-UHFFFAOYSA-N N-Butanol Chemical compound CCCCO LRHPLDYGYMQRHN-UHFFFAOYSA-N 0.000 description 2
- MYXYKQJHZKYWNS-UHFFFAOYSA-N barium neodymium Chemical compound [Ba][Nd] MYXYKQJHZKYWNS-UHFFFAOYSA-N 0.000 description 2
- 150000004649 carbonic acid derivatives Chemical class 0.000 description 2
- 235000019441 ethanol Nutrition 0.000 description 2
- 238000010304 firing Methods 0.000 description 2
- 239000000243 solution Substances 0.000 description 2
- VXUYXOFXAQZZMF-UHFFFAOYSA-N titanium(IV) isopropoxide Chemical compound CC(C)O[Ti](OC(C)C)(OC(C)C)OC(C)C VXUYXOFXAQZZMF-UHFFFAOYSA-N 0.000 description 2
- BVKZGUZCCUSVTD-UHFFFAOYSA-L Carbonate Chemical compound [O-]C([O-])=O BVKZGUZCCUSVTD-UHFFFAOYSA-L 0.000 description 1
- 239000004372 Polyvinyl alcohol Substances 0.000 description 1
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 1
- CPUJSIVIXCTVEI-UHFFFAOYSA-N barium(2+);propan-2-olate Chemical compound [Ba+2].CC(C)[O-].CC(C)[O-] CPUJSIVIXCTVEI-UHFFFAOYSA-N 0.000 description 1
- 239000003990 capacitor Substances 0.000 description 1
- 239000003985 ceramic capacitor Substances 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- RWGFKTVRMDUZSP-UHFFFAOYSA-N cumene Chemical group CC(C)C1=CC=CC=C1 RWGFKTVRMDUZSP-UHFFFAOYSA-N 0.000 description 1
- 239000012153 distilled water Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 239000007791 liquid phase Substances 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 239000004570 mortar (masonry) Substances 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- HZHUIQPXRWTHNF-UHFFFAOYSA-N neodymium(3+);propan-2-olate Chemical compound [Nd+3].CC(C)[O-].CC(C)[O-].CC(C)[O-] HZHUIQPXRWTHNF-UHFFFAOYSA-N 0.000 description 1
- 238000004806 packaging method and process Methods 0.000 description 1
- 229920002451 polyvinyl alcohol Polymers 0.000 description 1
- 238000010992 reflux Methods 0.000 description 1
- 238000005245 sintering Methods 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 230000002194 synthesizing effect Effects 0.000 description 1
- OGIDPMRJRNCKJF-UHFFFAOYSA-N titanium oxide Inorganic materials [Ti]=O OGIDPMRJRNCKJF-UHFFFAOYSA-N 0.000 description 1
Landscapes
- Inorganic Compounds Of Heavy Metals (AREA)
- Inorganic Insulating Materials (AREA)
Abstract
Description
【発明の詳細な説明】
（産業上の利用分野）
本発明は誘電体磁器粉末材料の−・つで比誘電率（ε２
）が大きく、高周波における誘電体損失（１１０）が小
さく、比誘電率の温度係数を広範囲に変化させることが
できるため、マイクロ波用誘電体共振器やコンデンサな
どの材料として広く使用されているネオジム・チタン酸
バリウム（Ｂ ａＯＮａｐｓ Ｔｉｅｓ ）の装造方
法に関するもので、更に詳しくは、最近の電子部品の小
形化、高性能化に伴って要求度が増加している数１−ミ
クロン程度のネオジム・チタン酸バリウム誘電体薄膜や
積層体等の用途に応じられる所の、高純度で高活性なネ
オジム・チタン酸バリウｌ、の微粉末材料の製造方法に
関するものである。DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to dielectric ceramic powder material having a relative dielectric constant (ε2
) is large, dielectric loss (110) is small at high frequencies, and the temperature coefficient of relative permittivity can be varied over a wide range, so neodymium is widely used as a material for dielectric resonators for microwaves, capacitors, etc.・This relates to the method for manufacturing barium titanate (BaONaps Ties), and more specifically, it concerns the packaging method for barium titanate (BaONaps Ties). The present invention relates to a method for producing a fine powder material of neodymium/barium titanate, which is highly pure and highly active and can be used for applications such as barium titanate dielectric thin films and laminates.
（従来の技術）
ネオジム・チタン酸バリウム誘電体磁器は、通常原料の
酸化ネオジム（Ｎｄ、 ０． ） 、酸化チタン（Ｔｉ
ｅｓ）％および炭酸バリウム（Ｂ ａ ＣＯｉ）粉末と
いった三種の出発原料を焼き固めて作製されるのが一般
的であるが、これら三種の粉末の合成法として従来から
知られている方法は、特公昭６０−４１８３３号公報で
開示されているように、前記の三種の粉末を混合し、こ
の混合物を乾燥した後、１０００℃前後の高温で反応さ
せる固相反応法が１：、であった。(Prior art) Neodymium-barium titanate dielectric porcelain is made from the usual raw materials neodymium oxide (Nd, 0.0%) and titanium oxide (Ti).
It is generally produced by sintering three types of starting materials: es)% and barium carbonate (B a COi) powder, but the conventionally known method for synthesizing these three types of powders is As disclosed in Japanese Publication No. 60-41833, 1: was a solid phase reaction method in which the three types of powders mentioned above were mixed, the mixture was dried, and then reacted at a high temperature of about 1000°C.
（発明が解決しようとする問題点）
しかしながら、Ｉ・、述した従来の固相反応法では、未
反応のネオジム、チタンやバリウム分が残るため、純度
があまり良くない１−に、粒径もミクロンオーダであっ
て、ネオジム・チタン酸バリウム誘電体薄膜や積層体用
としては不適であった。また、酸化物や炭酸塩の固相反
応１１、では、一般に高／＆Ｊ度の熱処理工程が必認で
あり、エネルギー消費の点からも好ましいものではなか
った。(Problems to be Solved by the Invention) However, in the conventional solid phase reaction method described above, unreacted neodymium, titanium, and barium components remain, resulting in poor purity and particle size. The size was on the order of microns, making it unsuitable for use in neodymium/barium titanate dielectric thin films or laminates. In addition, solid phase reaction 11 of oxides and carbonates generally requires a heat treatment step at a high temperature of 1/2°C, which is not preferable from the viewpoint of energy consumption.
本発明は、’Ｉ’：！Ｉ純度、高活性なネオジム・チタ
ン酸バリウムの微粉末を、従来のような高温熱処理を認
することなく、製造できる誘電体磁器粉末材料の製造方
法を提供しようとする点に目的を有する。The present invention is 'I':! The object of the present invention is to provide a method for producing a dielectric ceramic powder material that can produce a high-purity, highly active neodymium-barium titanate fine powder without requiring conventional high-temperature heat treatment.
（問題点を解決するための手段）
上記の［１的を達成するために、本発明に係る製造方法
は、バリウム、ネオジム、チタンをアルコールと反応さ
せて得られる各金属アルコキシドを出発原料とし、これ
らを所定の化学ｊＨ１比に混合したのち、この混合液を
５０〜１００℃に加熱しながら、この混合液に水を加え
て加水分解を好うことにより、ネオジム・チタン酸バリ
ウムの微粉末を得ることを特徴とするものである。(Means for solving the problem) In order to achieve the above [1], the production method according to the present invention uses each metal alkoxide obtained by reacting barium, neodymium, and titanium with alcohol as a starting material, After mixing these to a predetermined chemical jH1 ratio, the fine powder of neodymium/barium titanate is produced by adding water to the mixture while heating it to 50 to 100°C to facilitate hydrolysis. It is characterized by obtaining.
（実施例）
以ド、本発明に係る製造方法の実施例について説明する
。(Example) Hereinafter, an example of the manufacturing method according to the present invention will be described.
１モルの金属バリウムに１０モルのイソプロピルアルコ
ールを加え、ベンゼン溶媒とともに８２℃で還流してバ
リウムイソプロポキシドＢａ（ｉ−ＱＣ，Ｈ，Ｌ を作
製する。これに市販のネオジムイソプロポキシドＮｄ
（ｉ −０Ｃｓ Ｈｔ ）ｓのベンゼン溶液とチタニウ
ムテトライソプロポキシド’ｒｉ （ｉ −ＱＣｓ Ｈ
ｔ ）４ を酸化物換算でＢａ Ｏ： Ｎ ｄ Ｏ＋：
Ｔ ｔ Ｏｓ のモル比が表１の組成になるように加
える。これらの混合液は、再度２時間に亙って還流させ
ることによって均一・に４４合する。その後、これらの
混合液を１００〜５０℃の温度に加熱しながら、この混
合液に蒸溜水を少ｌＩｔずつ加えることにより、ベンゼ
ンとイソプロピルアルコールと水の共沸７ｕ度近傍のＩ
一度で加水分解反応を行わせ、結晶質のネオジム・チタ
ン酸バリウムの微粉末を析出させるのである。ここで、
イソプロピルアルコールの代わりにメチルアルコール、
エチルアルコール、ブチルアルコールを使用して同１−
の処理を行ってもネオジム・チタン酸バリウムの微粉末
が析出されることを知見した。Add 10 moles of isopropyl alcohol to 1 mole of metallic barium and reflux with benzene solvent at 82°C to prepare barium isopropoxide Ba (i-QC,H,L).To this, commercially available neodymium isopropoxide Nd
A benzene solution of (i -0Cs Ht )s and titanium tetraisopropoxide 'ri (i -QCs H
t)4 in terms of oxide: BaO: N d O+:
Add so that the molar ratio of T t Os becomes the composition shown in Table 1. These mixed solutions were refluxed again for 2 hours to uniformly combine them. Thereafter, while heating these mixtures to a temperature of 100 to 50°C, distilled water is added little by little to the mixture to form an azeotropic I of benzene, isopropyl alcohol, and water near 7u degrees.
The hydrolysis reaction is carried out at once, and a fine powder of crystalline neodymium/barium titanate is precipitated. here,
Methyl alcohol instead of isopropyl alcohol,
Same 1- using ethyl alcohol and butyl alcohol
It was discovered that fine powder of neodymium/barium titanate was precipitated even after this treatment.
このようにして得られた微粉末を、電子顕微鏡、 を
使用して粒径観察した結果によれば、各金属アルコキシ
ドの加水分解によって析出されたネオジム・チタン酸バ
リウム微粉末の大きさは、はぼ５０合ｍであって従来の
使用原料より約２桁程度小さいことがわかった。また得
られた微粉末を用いて、８００℃で２時間仮焼後、乳鉢
で粉砕機濃度３％のポリビニールアルコール溶液を加え
て造粒した。造粒粉体は金型と油圧プレスを用いて成形
圧力８００ ｋｇ／ｃ■１で直径２０冒會厚さ約１０．
簡の成形体に成形した後、アルミナさや鉢中で組成に応
じて１４００〜１１００℃の範囲の温度で２峙間保持し
て焼成し、表１に示す配合組成の誘電体磁器を得た。こ
のようにして得られた誘電体磁器の素ｒを用いて誘電体
共振器法によって比誘電率（ε、）と無負荷Ｑ （Ｑｕ
）を測定した。これらの測定における共振周波数は２〜
４ Ｇ Ｈ，であった。According to the results of particle size observation of the thus obtained fine powder using an electron microscope, the sizes of the neodymium/barium titanate fine powders precipitated by hydrolysis of each metal alkoxide are as follows: It was found that it was about 50 m, which is about two orders of magnitude smaller than the conventional raw materials used. Further, the obtained fine powder was calcined at 800° C. for 2 hours, and then granulated in a mortar by adding a polyvinyl alcohol solution with a grinder concentration of 3%. The granulated powder was molded using a mold and a hydraulic press under a molding pressure of 800 kg/cm 1 and a diameter of 20 mm and a thickness of approximately 10 mm.
After being formed into a simple compact, it was fired in an alumina sheath pot at a temperature in the range of 1400 to 1100° C. depending on the composition for two hours to obtain dielectric porcelain having the composition shown in Table 1. Using the dielectric ceramic element r obtained in this way, the relative permittivity (ε,) and the unloaded Q (Qu
) was measured. The resonant frequency in these measurements is 2~
It was 4GH.
それらの結果を表１に示す。表１において本印を付した
試料番号のものは酸化物と炭酸塩の原材料を用いた本発
明範囲外の比較例である。The results are shown in Table 1. Sample numbers marked with this mark in Table 1 are comparative examples outside the scope of the present invention, using oxide and carbonate raw materials.
表 １
を
表１から、本発明の方法により調整された誘電体磁器は
、市販の酸化物と炭酸塩を出発原料として高温で固相反
応させることから得られる試料に比べて高周波領域にお
ける誘電特性が優れているのみならず、誘電体ｋｌｉ器
を得る焼成ｌｉＪ度も従来の方法に比べて１５０〜１０
０℃低温で良くて、それだけ省エネルギーが図れる利点
を有することが明らかになったのである。Table 1 shows that the dielectric ceramic prepared by the method of the present invention has dielectric properties in the high frequency range compared to samples obtained by subjecting commercially available oxides and carbonates to solid phase reaction at high temperatures as starting materials. Not only is the firing rate superior to that of the conventional method, but the degree of firing to obtain a dielectric kli device is also 150 to 10
It has become clear that the temperature can be as low as 0°C, which has the advantage of saving energy.
（発明の効果）
以上説明したことからも理解されるように、本発明の製
造方法によれば、各金属アルコオキサイドを出発原料と
して、これらの液相反応であって、従来法のような高温
度の熱処理工程を経ることなく、省エネルギーのもとで
、高純度で高活性なネオジム・チタン酸バリウムの微粉
末を得ることができるから、この微粉末材料を利用して
誘電特性に優れた誘電体磁器を得ることができる。また
、本発明方法により得られる粉末は、その粒子径が数ト
ミクロン程度の非常に小さいものであるために、薄い誘
電体層を７堡とする積層型磁器コンデンサ用材料等とし
て広範な用途性を有し、１−業的価値は絶大である。(Effects of the Invention) As can be understood from the above explanation, according to the production method of the present invention, each metal alkoxide is used as a starting material, and these liquid phase reactions are carried out at a high temperature, unlike the conventional method. High purity and highly active neodymium/barium titanate fine powder can be obtained without going through a temperature heat treatment process and with energy savings. You can get body porcelain. In addition, since the powder obtained by the method of the present invention has a very small particle size of several tommicrons, it has a wide range of uses, such as as a material for multilayer ceramic capacitors with seven layers of thin dielectric material. 1- The commercial value is tremendous.
Claims (1)
て得られる各金属アルコキシドを出発原料とし、これら
を所定の化学量比に混合したのち、この混合液を５０〜
１００℃に加熱しながらこの混合液に水を加えて加水分
解を行うことにより、ネオジム・チタン酸バリウムの微
粉末を得ることを特徴とする誘電体磁器粉末材料の製造
方法。Each metal alkoxide obtained by reacting barium, neodymium, and titanium with alcohol is used as a starting material, and after mixing these at a predetermined stoichiometric ratio, this mixed solution is
A method for producing a dielectric porcelain powder material, characterized in that a fine powder of neodymium/barium titanate is obtained by adding water to this mixed solution while heating it to 100° C. to perform hydrolysis.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8744886A JPS62241822A (en) | 1986-04-15 | 1986-04-15 | Production of porcelain powder material of dielectric material |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8744886A JPS62241822A (en) | 1986-04-15 | 1986-04-15 | Production of porcelain powder material of dielectric material |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS62241822A true JPS62241822A (en) | 1987-10-22 |
Family
ID=13915137
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP8744886A Pending JPS62241822A (en) | 1986-04-15 | 1986-04-15 | Production of porcelain powder material of dielectric material |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS62241822A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4929436A (en) * | 1987-03-26 | 1990-05-29 | Solvay & Cie (Societe Anonyme) | Process for the manufacture of a powder of mixed metal oxides, and mixed metal oxide powders |
-
1986
- 1986-04-15 JP JP8744886A patent/JPS62241822A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4929436A (en) * | 1987-03-26 | 1990-05-29 | Solvay & Cie (Societe Anonyme) | Process for the manufacture of a powder of mixed metal oxides, and mixed metal oxide powders |
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