JPH0240002B2 - - Google Patents
Info
- Publication number
- JPH0240002B2 JPH0240002B2 JP59264622A JP26462284A JPH0240002B2 JP H0240002 B2 JPH0240002 B2 JP H0240002B2 JP 59264622 A JP59264622 A JP 59264622A JP 26462284 A JP26462284 A JP 26462284A JP H0240002 B2 JPH0240002 B2 JP H0240002B2
- Authority
- JP
- Japan
- Prior art keywords
- particle size
- strontium titanate
- powder
- present
- average particle
- 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.)
- Expired - Lifetime
Links
- 239000002245 particle Substances 0.000 claims description 57
- 239000000843 powder Substances 0.000 claims description 31
- VEALVRVVWBQVSL-UHFFFAOYSA-N strontium titanate Chemical compound [Sr+2].[O-][Ti]([O-])=O VEALVRVVWBQVSL-UHFFFAOYSA-N 0.000 claims description 27
- 238000000634 powder X-ray diffraction Methods 0.000 claims description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 10
- 229910001868 water Inorganic materials 0.000 description 10
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 7
- 239000003990 capacitor Substances 0.000 description 7
- 238000005259 measurement Methods 0.000 description 5
- 238000005245 sintering Methods 0.000 description 4
- KFZMGEQAYNKOFK-UHFFFAOYSA-N Isopropanol Chemical compound CC(C)O KFZMGEQAYNKOFK-UHFFFAOYSA-N 0.000 description 3
- 239000013078 crystal Substances 0.000 description 3
- 229910001873 dinitrogen Inorganic materials 0.000 description 3
- 230000000704 physical effect Effects 0.000 description 3
- 238000004626 scanning electron microscopy Methods 0.000 description 3
- LLZRNZOLAXHGLL-UHFFFAOYSA-J titanic acid Chemical compound O[Ti](O)(O)O LLZRNZOLAXHGLL-UHFFFAOYSA-J 0.000 description 3
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 description 2
- 238000002441 X-ray diffraction Methods 0.000 description 2
- 238000007664 blowing Methods 0.000 description 2
- 238000001493 electron microscopy Methods 0.000 description 2
- 238000009766 low-temperature sintering Methods 0.000 description 2
- 229910052757 nitrogen Inorganic materials 0.000 description 2
- 238000001878 scanning electron micrograph Methods 0.000 description 2
- 239000012798 spherical particle Substances 0.000 description 2
- 238000003756 stirring Methods 0.000 description 2
- UUCCCPNEFXQJEL-UHFFFAOYSA-L strontium dihydroxide Chemical compound [OH-].[OH-].[Sr+2] UUCCCPNEFXQJEL-UHFFFAOYSA-L 0.000 description 2
- 229910001866 strontium hydroxide Inorganic materials 0.000 description 2
- UJPWWRPNIRRCPJ-UHFFFAOYSA-L strontium;dihydroxide;octahydrate Chemical compound O.O.O.O.O.O.O.O.[OH-].[OH-].[Sr+2] UJPWWRPNIRRCPJ-UHFFFAOYSA-L 0.000 description 2
- OGIDPMRJRNCKJF-UHFFFAOYSA-N titanium oxide Inorganic materials [Ti]=O OGIDPMRJRNCKJF-UHFFFAOYSA-N 0.000 description 2
- -1 PTC elements Substances 0.000 description 1
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 1
- 238000009835 boiling Methods 0.000 description 1
- 239000003985 ceramic capacitor Substances 0.000 description 1
- 239000007795 chemical reaction product Substances 0.000 description 1
- 239000002270 dispersing agent Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000010292 electrical insulation Methods 0.000 description 1
- 238000001704 evaporation Methods 0.000 description 1
- 230000008020 evaporation Effects 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- BDAGIHXWWSANSR-NJFSPNSNSA-N hydroxyformaldehyde Chemical compound O[14CH]=O BDAGIHXWWSANSR-NJFSPNSNSA-N 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 239000012299 nitrogen atmosphere Substances 0.000 description 1
- 229910000510 noble metal Inorganic materials 0.000 description 1
- 239000003921 oil Substances 0.000 description 1
- 238000012856 packing Methods 0.000 description 1
- 239000011148 porous material Substances 0.000 description 1
- 238000010992 reflux Methods 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
- 229910052710 silicon Inorganic materials 0.000 description 1
- 239000010703 silicon Substances 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 238000001179 sorption measurement Methods 0.000 description 1
- 229910000018 strontium carbonate Inorganic materials 0.000 description 1
- 239000006228 supernatant Substances 0.000 description 1
Description
（産業上の利用分野）
本発明は、小粒径で比表面積が小さく、粒度分
布が狭い、球形状の新規なチタン酸ストロンチウ
ム粉末に関するものである。さらには、低温焼結
可能である新規なチタン酸ストロンチウム粉末に
関するものである。
現在、チタン酸ストロンチウムは、コンデンサ
ー、PTC素子、半導体等として、電子部品分野
で広く応用されている。
（従来の技術）
近年、電子部品はますます小型化の傾向があ
る。例えば、コンデンサーもその類にたがわず、
小型化高容量化が望まれており、これを実現する
ものとして、積層コンデンサーが注目が集めてい
る。現在、積層コンデンサーでは、さらに電極間
距離を10〜20μと少さくして高容量化を促進する
傾向にある。この要求を満足し、コンデンサーの
性能および信頼性を保証するため、かかるセラミ
ツクコンデンサーでは、電極間で焼結体を構成す
る粒子をできるだけ数多く、均一に存在させるこ
とが望ましい。しかし、例えば、焼結に1300℃以
上を要することは、高価な貴金属内部電極を必要
とするため、電極コストを引き上げる原因とな
り、さらに、焼結体中の粒子も粒生長により大き
くなるため、電極間距離を短かくできず、高容量
化を阻害する原因となり、また、物性や寸法精度
がバラつくことは、歩留まり低下をもたらし、コ
スト高の原因となる。このため、上記欠点は改善
されることが強く望まれていた。また、このこと
は、積層コンデンサー以外の電子部品についても
同様に強く要望されていた。しかし、これらの諸
要求を満足させるチタン酸ストロンチウム粉末
は、従来知されていなかつた。
（発明が解決しようとする問題）
これまで、チタン酸ストロンチウム粉末は、大
粒径のものや、小粒径ではあるが分散性が悪く、
粒径や形状が不均一な粒末のみが知られていた。
大粒径のものや、強度に凝集したものは、見かけ
上一個の粒子として挙動するため、焼結開始温度
が1100℃以上で、相対密度を90％以上にするに
は、1300℃以上の高温を必要とする。また、分散
性が悪いものや、粒径および形状が不均一の粉
は、均一な充填構造をとることが難かしく、焼結
も均一に進行せず、寸法精度や物性のバラツキの
原因となつている。さらに、粒径が0.05μ程度以
下の超微粉では、ハンドリング性が非常に悪く、
均一な成形体を得ることが難かしく、信頼性の高
い焼結体が得られ難いという欠点を有していた。
（問題点を解決するための手段）
本発明者らは、より低い温度で、均一なチタン
酸ストロンチウム焼結体を製造するため鋭意研究
を重ねた結果、微細で結晶子径が粒径に近く、均
一粒径および均一形状を有するチタン酸ストロン
チウム粉末を見出し、本発明を完成するに至つ
た。
すなわち、本発明は、平均粒径が0.07〜0.5μ、
比表面積が３〜20m2／ｇで、かつ粒径を真球と仮
定して平均粒径から計算される値の2.5倍を越え
ない値であり、粉末Ｘ線回折像のピークの半値巾
から計算される結晶子径が0.05μ以上0.4μ以下で、
その形状が球形状であることを特徴とするチタン
酸ストロンチウム粉末に関するものである。
本発明でいう球形状とは、図面の走査型電子顕
微鏡写真で見るように、粒子一個の形状が全体と
して球に近似していることを言う。
本発明のチタン酸ストロンチウムは、走査型電
子顕微鏡（例えば、日立製作所(株)製Ｓ−430型走
査電子顕微鏡）観察により、その粒径および形状
についての測定を行うことができる。
本発明のチタン酸ストロンチウムは、平均粒径
が0.07〜0.5μの範囲にあるが、どの粒子もほぼ同
一の粒径を有しており、標準偏差値は1.5以下で
ある。本発明において、走査型電子顕微鏡観察に
よつて求める平均粒径および標準偏差値αは、
単位視野内に見えるｎ個の粒子の粒径χiを測定
し、次式により算出される。
ただし、
(Industrial Application Field) The present invention relates to a novel spherical strontium titanate powder having a small particle size, a small specific surface area, and a narrow particle size distribution. Furthermore, the present invention relates to a novel strontium titanate powder that can be sintered at low temperatures. Currently, strontium titanate is widely applied in the field of electronic components as capacitors, PTC elements, semiconductors, etc. (Prior Art) In recent years, there has been a tendency for electronic components to become more and more compact. For example, capacitors are of the same type.
There is a desire for smaller size and higher capacity, and multilayer capacitors are attracting attention as a way to achieve this. Currently, in multilayer capacitors, there is a trend to further reduce the distance between electrodes to 10 to 20 microns to promote higher capacitance. In order to satisfy this requirement and guarantee the performance and reliability of the capacitor, in such a ceramic capacitor, it is desirable that the particles constituting the sintered body exist uniformly as much as possible between the electrodes. However, for example, requiring a temperature of 1,300°C or higher for sintering requires expensive noble metal internal electrodes, which increases electrode costs.Furthermore, the particles in the sintered body become larger due to grain growth, so the electrode The inability to shorten the distance between the two leads to an impediment to higher capacity, and variations in physical properties and dimensional accuracy lead to lower yields and higher costs. Therefore, it has been strongly desired that the above drawbacks be improved. Moreover, this is also strongly desired for electronic components other than multilayer capacitors. However, strontium titanate powder that satisfies these requirements has not been known so far. (Problem to be Solved by the Invention) Until now, strontium titanate powders have been available in large particle sizes, and in small particle sizes with poor dispersibility.
Only powders with non-uniform particle size and shape were known.
Large particles or strongly agglomerated particles appear to behave as a single particle, so if the sintering start temperature is 1100℃ or higher and the relative density is 90% or higher, a high temperature of 1300℃ or higher is required. Requires. In addition, powder with poor dispersibility or uneven particle size and shape makes it difficult to form a uniform packing structure, and sintering does not proceed uniformly, causing variations in dimensional accuracy and physical properties. ing. Furthermore, ultrafine powder with a particle size of about 0.05μ or less has very poor handling.
It has the disadvantage that it is difficult to obtain a uniform molded body and it is difficult to obtain a highly reliable sintered body. (Means for solving the problem) As a result of intensive research to produce a uniform strontium titanate sintered body at a lower temperature, the present inventors found that the crystallite size is fine and the crystallite size is close to the particle size. They discovered strontium titanate powder having a uniform particle size and uniform shape, and completed the present invention. That is, in the present invention, the average particle size is 0.07 to 0.5μ,
A value that does not exceed 2.5 times the value calculated from the average particle size assuming that the specific surface area is 3 to 20 m 2 /g and that the particle size is a true sphere, and from the half-width of the peak in the powder X-ray diffraction image. The calculated crystallite diameter is 0.05μ or more and 0.4μ or less,
The present invention relates to strontium titanate powder characterized by its spherical shape. The spherical shape in the present invention refers to the shape of each particle as a whole resembling a sphere, as seen in the scanning electron micrograph of the drawing. The particle size and shape of the strontium titanate of the present invention can be measured by observation using a scanning electron microscope (for example, Model S-430 scanning electron microscope manufactured by Hitachi, Ltd.). The strontium titanate of the present invention has an average particle size in the range of 0.07 to 0.5μ, but all particles have almost the same particle size, and the standard deviation value is 1.5 or less. In the present invention, the average particle diameter and standard deviation value α determined by scanning electron microscopy are as follows:
The particle diameter χ i of n particles visible within a unit field of view is measured and calculated by the following formula. however,
【式】
さらに、本発明のチタン酸ストロンチウムは、
どの粒子もほぼ球形状をしており、一個の粒子の
最長径と最短径の差を最長径で割つた値は3/10以
下である。
また、粉末の分散性は、粒度分布を測定するこ
とにより把握できる。粒度分布は、例えばセイシ
ン企業(株)ミクロン・フオート・サイザーSKA−
5000により容易に測定できる。本発明者らは、チ
タン酸ストロンチウム粉末をイソプロピルアルコ
ールに分散し、分散剤としてPEGを微量加えて、
その粒度分布を測定した。
本発明のチタン酸ストロンチウムは、粒度分布
測定によつて測定される平均粒径が、前記走査型
電子顕微鏡観察より測定される平均粒径と概ね一
致し、さらに、粒度分布が狭く、その標準偏差値
は2.0以下である。ただし、本発明で粒度分布測
定によつて求める平均粒径および標準偏差値α
は、次式によつて算出される。
ただし、
[Formula] Furthermore, the strontium titanate of the present invention is
All particles are almost spherical, and the difference between the longest and shortest diameters of a single particle divided by the longest diameter is less than 3/10. Further, the dispersibility of the powder can be understood by measuring the particle size distribution. The particle size distribution is, for example, Seishin Enterprise Co., Ltd. Micron Photo Sizer SKA-
5000 can be easily measured. The present inventors dispersed strontium titanate powder in isopropyl alcohol, added a small amount of PEG as a dispersant, and
The particle size distribution was measured. The strontium titanate of the present invention has an average particle size measured by particle size distribution measurement that roughly matches the average particle size measured by the above-mentioned scanning electron microscope observation, and further has a narrow particle size distribution and a standard deviation thereof. The value is less than or equal to 2.0. However, the average particle diameter and standard deviation value α determined by particle size distribution measurement in the present invention
is calculated by the following formula. however,
【式】
上式において、χiは粒径で当該微小測定範囲両
端の相加平均、νiは粒径χiの粒子が占める体積分
率、ｎは当該微小測定範囲の数である。
本発明において、結晶子径は粉末Ｘ線回折像の
ピークの半値巾を測定し、シエラの式
Ｌ＝Kλ／βcosθ
に代入することにより求めることができる。上記
式でＬは結晶子径、λはＸ線の波長、βはピーク
の半値巾、θはＸ線の回折角、Ｋは定数で本発明
の場合0.9とした。半値巾βの値は、測定される
粉末Ｘ線回折像のピーク形状をコーシー分布と仮
定し、シリコン結晶を使つて補正することにより
求める。
本発明で提供するチタン酸ストロンチウム粉末
について、上式を用いて算出する結晶子径は、前
記走査型電子顕微鏡観察により測定される平均粒
径とよい一致を示す。すなわち、概ね一個の粒子
は一個ないし数個の結晶子で成り立つている。
本発明において、比表面積はガス吸着型の比表
面積測定機、例えばカルロエルバ(株)製ソープトマ
チツク1800により測定できる。
本発明のチタン酸ストロンチウム粉末の比表面
積は、30〜20m2／ｇの範囲にあるが、チタン酸ス
トロンチウム粉末が球状で微細孔や凸凹を持たな
いと仮定して計算される粒径は、前記走査型電子
顕微鏡観察により測定される平均粒径の４割以下
とはらならずほぼ一致する。したがつて、この点
からも本発明で提供するチタン酸ストロンチウム
粉末が細孔などを持たないほぼ球形状の粒子であ
ることが確認できる。
本発明のチタン酸ストロンチウム粉末の製法
は、前記性状を与える方法である限り特に限定さ
れるものではないが、たとえば含水酸化チタンと
水酸化ストロンチウムを応させることにより製造
することができる。
この反応は、含水酸化チタン、水酸化ストロン
チウムおよび水を窒素雰囲気下で撹拌混合しつつ
加熱すると都合よく進行し、所望の粒末が得られ
る。反応温度は60℃以上110℃未満の温度を選択
するが、反応速度および装置の簡略化等を考慮す
れば100℃が適当である。また、反応温度、溶媒
および濃度を適当に選べば、0.07μから0.5μの範
囲で所望の平均粒径を有する粉末を得ることがで
きる。
このようにして合成されるチタン酸ストロンチ
ウム粉末は、常法にしたがつて、過し、水洗
し、再び過し、乾燥して取り出すことができ
る。
（発明の効果）
本発明のチタン酸ストロンチウム粉末は、公知
のチタン酸ストロンチウム粉末に比べ焼結温度が
100℃以上も低く、かつ均一な微構造の焼結体を
与え、低温焼結用チタン酸ストロンチウム粉末と
して実用上極めて有用なものである。特に積層コ
ンデンサでは、電気絶縁性を高め、電極コストを
下げるために、低温焼結用チタン酸ストロンチウ
ム粉末が切望されているが、本発明で提供するチ
タン酸ストロンチウム粉末は、この要求を満たす
ものであり、極めて有用なものである。
（実施例）
次に、実施例によつて本発明をさらに詳細に説
明する。
実施例 １
含水率95％のゲル状オルトチタン酸0.5モルを
水0.5と共に反応器中へ入れ、窒素ガスを吹き
込みつつ、約15時間放置した。一方、水酸化スト
ロンチウム（８水和物）270ｇを90℃の水２に
溶解し、沸とう後、炭酸ストロンチウムを除くた
め過し、液を空気に触れさせないよう窒素ガ
スの下で充分注意を払いつつ、オルトチタン酸と
水を入れて放置してある反応器中に入れた。この
反応器に窒素を流しながら、さらに撹拌混合しつ
つ、オイルバスで100℃に加熱し、８時間反応を
行なつた。反応終了後、約10分間放置し、上澄液
を除去し、さらに熱水２を加えて撹拌洗浄後、
過した。この操作を合計３回繰り返した後、乾
燥し白色粉末を得た。このようにして得られた粉
末について、走査型電子顕微鏡観察およびＸ線回
折解析を行なつた。平均粒径0.16μ、標準偏差
1.35の均一球状粒子からなり、立方晶の結晶子径
が0.09μチタン酸ストロンチウム粉末であつた。
さらに、比表面積を測定したところ、比表面積値
は9.5m2／ｇであり、電子顕微鏡観察による平均
粒径から計算される値とよい一致を示した。ま
た、粒度分布測定装置より、平均粒径0.30μ、標
準偏差値1.82の値が得られ、分散性のよい粒末で
あつた。
実施例 ２
含水率96％のオルトチタン酸１モルを水２と
共に反応器中へ入れ、窒素ガスを吹き込みつつ、
約一晩放置した。水酸化ストロンチウム（８水和
物）750ｇを95℃の水７に溶解し、過後、反
応容器に加えた。窒素を流しながら沸とう還流下
で４時間反応を行なわせた。得られた反応生成物
を実施例と同様に処理し、得られた粉の物性を測
定した。電子顕微鏡観察による平均粒径は0.23μ
であり、標準偏差は1.45の球状粒子で、比表面積
は7.2m2／ｇであつた。Ｘ線回折解析から、結晶
子径は0.11μである立方晶であることが判つた。
また、粒度分布測定では、平均粒径0.45μ、標準
偏差値は1.93であつた。[Formula] In the above formula, χ i is the particle size and is the arithmetic average of both ends of the micro measurement range, ν i is the volume fraction occupied by particles with the particle size χ i , and n is the number of the micro measurement ranges. In the present invention, the crystallite diameter can be determined by measuring the half width of a peak in a powder X-ray diffraction image and substituting it into Sierra's equation L=Kλ/βcosθ. In the above formula, L is the crystallite diameter, λ is the wavelength of the X-ray, β is the half-width of the peak, θ is the diffraction angle of the X-ray, and K is a constant, which is 0.9 in the case of the present invention. The value of the half-width β is determined by assuming that the peak shape of the powder X-ray diffraction image to be measured is a Cauchy distribution, and correcting it using a silicon crystal. Regarding the strontium titanate powder provided by the present invention, the crystallite diameter calculated using the above formula shows good agreement with the average particle diameter measured by the scanning electron microscope observation. That is, one particle generally consists of one to several crystallites. In the present invention, the specific surface area can be measured using a gas adsorption type specific surface area measuring device, for example, Soaptomatic 1800 manufactured by Carlo Erba. The specific surface area of the strontium titanate powder of the present invention is in the range of 30 to 20 m 2 /g, but the particle size calculated assuming that the strontium titanate powder is spherical and does not have micropores or irregularities is as follows. The average particle size is not less than 40% of the average particle size measured by scanning electron microscopy, but it is almost the same. Therefore, from this point as well, it can be confirmed that the strontium titanate powder provided by the present invention is a substantially spherical particle having no pores. The method for producing the strontium titanate powder of the present invention is not particularly limited as long as it provides the above-mentioned properties, but it can be produced, for example, by reacting hydrous titanium oxide and strontium hydroxide. This reaction proceeds conveniently when hydrous titanium oxide, strontium hydroxide, and water are stirred and heated under a nitrogen atmosphere, and the desired particle powder is obtained. The reaction temperature is selected to be 60°C or higher and lower than 110°C, but 100°C is appropriate in consideration of reaction rate and equipment simplification. Further, by appropriately selecting the reaction temperature, solvent and concentration, it is possible to obtain a powder having a desired average particle size in the range of 0.07μ to 0.5μ. The strontium titanate powder synthesized in this manner can be filtered, washed with water, filtered again, dried, and taken out in a conventional manner. (Effects of the invention) The strontium titanate powder of the present invention has a lower sintering temperature than known strontium titanate powders.
It produces a sintered body with a uniform microstructure at temperatures as low as 100°C or more, making it extremely useful in practice as a strontium titanate powder for low-temperature sintering. In particular, in multilayer capacitors, strontium titanate powder for low-temperature sintering is in high demand in order to improve electrical insulation and reduce electrode costs, but the strontium titanate powder provided by the present invention does not meet this demand. Yes, it is extremely useful. (Example) Next, the present invention will be explained in more detail with reference to Examples. Example 1 0.5 mol of gel-like orthotitanic acid with a water content of 95% was put into a reactor along with 0.5 mol of water, and the reactor was left to stand for about 15 hours while blowing nitrogen gas. On the other hand, dissolve 270 g of strontium hydroxide (octahydrate) in water 2 at 90°C, boil it, filter it to remove strontium carbonate, and take great care under nitrogen gas to prevent the solution from coming into contact with air. Meanwhile, orthotitanic acid and water were placed in a reactor that had been left standing. While flowing nitrogen into the reactor and stirring and mixing, the reactor was heated to 100° C. in an oil bath and reacted for 8 hours. After the reaction was completed, leave it for about 10 minutes, remove the supernatant liquid, add hot water 2 and wash with stirring.
passed. After repeating this operation three times in total, it was dried to obtain a white powder. The powder thus obtained was subjected to scanning electron microscopy and X-ray diffraction analysis. Average particle size 0.16μ, standard deviation
The strontium titanate powder consisted of uniform spherical particles of 1.35 mm and had a cubic crystallite size of 0.09 μm.
Furthermore, when the specific surface area was measured, the specific surface area value was 9.5 m 2 /g, which showed good agreement with the value calculated from the average particle size observed by electron microscopy. Further, the average particle diameter was 0.30 μm and the standard deviation value was 1.82 using a particle size distribution measuring device, indicating that the powder had good dispersibility. Example 2 1 mole of orthotitanic acid with a water content of 96% was put into a reactor together with 2 parts of water, and while blowing nitrogen gas,
It was left for about one night. 750 g of strontium hydroxide (octahydrate) was dissolved in water 7 at 95°C, and after evaporation, it was added to the reaction vessel. The reaction was carried out under boiling and reflux for 4 hours while flowing nitrogen. The obtained reaction product was treated in the same manner as in the example, and the physical properties of the obtained powder were measured. The average particle size according to electron microscopy is 0.23μ
The particles were spherical with a standard deviation of 1.45 and a specific surface area of 7.2 m 2 /g. X-ray diffraction analysis revealed that it was a cubic crystal with a crystallite diameter of 0.11μ.
Further, in particle size distribution measurement, the average particle diameter was 0.45μ, and the standard deviation value was 1.93.
図面は実施例１において合成したチタン酸スト
ロンチウム粉末の結晶構造を示す倍率50000倍の
走査型電子顕微鏡写真である。
The drawing is a scanning electron micrograph at a magnification of 50,000 times showing the crystal structure of the strontium titanate powder synthesized in Example 1.
Claims (1)
m2／ｇで、かつ粒形を真球と仮定して平均粒径か
ら計算される値の2.5倍を越えない値であり、粉
末Ｘ線回折像のピークの半値巾から計算される結
晶子径が0.05μ以上0.4μ以下で、その形状が球形
状であることを特徴とするチタン酸ストロンチウ
ム粉末。1 Average particle size is 0.07~0.5μ, specific surface area is 3~20
m 2 /g, and the value does not exceed 2.5 times the value calculated from the average particle size assuming that the particle shape is a true sphere, and the crystallite value calculated from the half-width of the peak of the powder X-ray diffraction image. A strontium titanate powder characterized by having a diameter of 0.05μ or more and 0.4μ or less and a spherical shape.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP26462284A JPS61146709A (en) | 1984-12-17 | 1984-12-17 | Strontium titanate powder |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP26462284A JPS61146709A (en) | 1984-12-17 | 1984-12-17 | Strontium titanate powder |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS61146709A JPS61146709A (en) | 1986-07-04 |
| JPH0240002B2 true JPH0240002B2 (en) | 1990-09-10 |
Family
ID=17405889
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP26462284A Granted JPS61146709A (en) | 1984-12-17 | 1984-12-17 | Strontium titanate powder |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS61146709A (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP5566183B2 (en) * | 2010-05-17 | 2014-08-06 | 京セラ株式会社 | Dielectric powder and sintered body and capacitor using the same |
| JP6583637B2 (en) * | 2014-03-31 | 2019-10-02 | 戸田工業株式会社 | Strontium titanate fine particle powder and method for producing the same |
| CN105502480B (en) * | 2015-10-16 | 2017-03-22 | 浙江大学 | Hydrangea-like strontium titanate nano powder preparation method |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5864218A (en) * | 1981-10-09 | 1983-04-16 | Kyoritsu Yogyo Genryo Kk | Manufacture of strontium titanate |
| JPS5945928A (en) * | 1982-09-08 | 1984-03-15 | Sony Corp | Preparation of fine particle from strontium titanate |
-
1984
- 1984-12-17 JP JP26462284A patent/JPS61146709A/en active Granted
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5864218A (en) * | 1981-10-09 | 1983-04-16 | Kyoritsu Yogyo Genryo Kk | Manufacture of strontium titanate |
| JPS5945928A (en) * | 1982-09-08 | 1984-03-15 | Sony Corp | Preparation of fine particle from strontium titanate |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS61146709A (en) | 1986-07-04 |
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