JPS622682B2 - - Google Patents
Info
- Publication number
- JPS622682B2 JPS622682B2 JP56214551A JP21455181A JPS622682B2 JP S622682 B2 JPS622682 B2 JP S622682B2 JP 56214551 A JP56214551 A JP 56214551A JP 21455181 A JP21455181 A JP 21455181A JP S622682 B2 JPS622682 B2 JP S622682B2
- Authority
- JP
- Japan
- Prior art keywords
- barium titanate
- particles
- resistance
- semiconducting
- semiconductive
- 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
Links
- JRPBQTZRNDNNOP-UHFFFAOYSA-N barium titanate Chemical compound [Ba+2].[Ba+2].[O-][Ti]([O-])([O-])[O-] JRPBQTZRNDNNOP-UHFFFAOYSA-N 0.000 claims description 37
- 229910002113 barium titanate Inorganic materials 0.000 claims description 37
- 239000002245 particle Substances 0.000 claims description 29
- 239000000463 material Substances 0.000 claims description 12
- 229910052751 metal Inorganic materials 0.000 claims description 12
- 239000002184 metal Substances 0.000 claims description 12
- 238000010304 firing Methods 0.000 claims description 9
- 239000011164 primary particle Substances 0.000 claims description 9
- 239000011163 secondary particle Substances 0.000 description 10
- 238000000465 moulding Methods 0.000 description 7
- 238000010586 diagram Methods 0.000 description 6
- 239000008187 granular material Substances 0.000 description 6
- 239000000203 mixture Substances 0.000 description 6
- 239000000758 substrate Substances 0.000 description 6
- 238000000034 method Methods 0.000 description 4
- 239000008188 pellet Substances 0.000 description 4
- 230000007423 decrease Effects 0.000 description 3
- 239000000523 sample Substances 0.000 description 3
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 2
- 229910052788 barium Inorganic materials 0.000 description 2
- DSAJWYNOEDNPEQ-UHFFFAOYSA-N barium atom Chemical compound [Ba] DSAJWYNOEDNPEQ-UHFFFAOYSA-N 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 239000012212 insulator Substances 0.000 description 2
- 239000000843 powder Substances 0.000 description 2
- 239000002994 raw material Substances 0.000 description 2
- 239000011347 resin Substances 0.000 description 2
- 229920005989 resin Polymers 0.000 description 2
- 239000002904 solvent Substances 0.000 description 2
- 229910052684 Cerium Inorganic materials 0.000 description 1
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 229910052787 antimony Inorganic materials 0.000 description 1
- 229910052797 bismuth Inorganic materials 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 238000009408 flooring Methods 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 229910052738 indium Inorganic materials 0.000 description 1
- 150000002500 ions Chemical class 0.000 description 1
- 229910052746 lanthanum Inorganic materials 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- 229910052758 niobium Inorganic materials 0.000 description 1
- QKKWJYSVXDGOOJ-UHFFFAOYSA-N oxalic acid;oxotitanium Chemical compound [Ti]=O.OC(=O)C(O)=O QKKWJYSVXDGOOJ-UHFFFAOYSA-N 0.000 description 1
- 238000005096 rolling process Methods 0.000 description 1
- 238000007873 sieving Methods 0.000 description 1
- 239000007858 starting material Substances 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 229910052718 tin Inorganic materials 0.000 description 1
Landscapes
- Compositions Of Oxide Ceramics (AREA)
- Thermistors And Varistors (AREA)
Description
【発明の詳細な説明】
本発明は、正の抵抗温度係数（PTCR特性とい
う）を示し、二次焼成を必要としない半導性チタ
ン酸バリウム材料に関するものである。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a semiconductive barium titanate material that exhibits a positive temperature coefficient of resistance (referred to as PTCR characteristics) and does not require secondary firing.
半導性チタン酸バリウムセラミツクスは、その
キユリー点以上の温度で異常なPTCR特性を示
し、その特性を利用して自己制御型発熱体等種々
の用途に用いられている。 Semiconducting barium titanate ceramics exhibit unusual PTCR characteristics at temperatures above their Curie point, and this property is used in various applications such as self-regulating heating elements.
従来、このような半導性チタン酸バリウムは焼
結体材料においてのみ実用化されている。薄膜お
よび厚膜の膜状の形態においては、粉末状の半導
性チタン酸バリウムを基板に塗布し二次焼成して
膜状にする方法が試みられているが、焼成時の基
板との反応に問題点が多く、また、焼成過程を含
むため、樹脂等の基板に膜状の半導性チタン酸バ
リウムを形成することは困難であり、未だ実用化
に至つていない。 Conventionally, such semiconductive barium titanate has been put to practical use only as a sintered material. In the form of thin and thick films, attempts have been made to apply semiconductive barium titanate in powder form to a substrate and perform secondary firing to form a film, but the reaction with the substrate during firing has been attempted. There are many problems with this method, and since it involves a firing process, it is difficult to form a film of semiconductive barium titanate on a substrate such as a resin, and it has not yet been put to practical use.
本発明は、従来のこのような二次焼成を必要と
する半導性チタン酸バリウムの問題点に注目し、
二次焼成を必要としない半導性チタン酸バリウム
材料を開発することにより、種々の形状の半導性
チタン酸バリウム製品の製造を可能にしたもので
ある。 The present invention focuses on the problems of conventional semiconducting barium titanate that requires secondary firing,
By developing a semiconductive barium titanate material that does not require secondary firing, it has become possible to manufacture semiconductive barium titanate products in various shapes.
即ち、本発明は、粒径２〜20μｍの均一な１次
粒子が複数個粒界結合した粒径10〜200μｍの半
導性チタン酸バリウム粒体（２次粒子）に、その
粒体に対しオーム性の接触をする金属を５〜20重
量％添加混合し、前記半導性チタン酸バリウム粒
体を前記オーム性の接触をする金属を介して連結
した二次焼成を必要としない半導性チタン酸バリ
ウム材料を要旨とするものである。 That is, the present invention provides semiconductive barium titanate granules (secondary particles) with a particle size of 10 to 200 μm, in which a plurality of uniform primary particles with a particle size of 2 to 20 μm are bonded at grain boundaries, and A semiconductive material that does not require secondary firing, in which 5 to 20% by weight of a metal that makes ohmic contact is added and mixed, and the semiconductive barium titanate particles are connected through the metal that makes ohmic contact. The gist is barium titanate material.
ここで、半導性チタン酸バリウム粒体とは第１
図に示すように、半導性化元素として例えば
Nb，Sb，Bi，La，Ce等のイオンをチタン酸バリ
ウム粒子内に固溶させた均一な１次粒子１が複数
個粒界接触４して、２次粒子２を形成しているも
のであり、個々の２次粒子２がPTCR特性を有す
るものである。１次粒子の粒径は２〜20μｍであ
ることが好ましく、20μｍ以上ではキユリー点以
上での最大抵抗値が下がりPTCR効果が小さくな
り、また２μｍ以下では室温での抵抗値が高くな
り、絶縁体特性を示すようになるという欠点があ
る。 Here, semiconducting barium titanate particles are
As shown in the figure, examples of semiconducting elements include
A plurality of uniform primary particles 1 in which ions such as Nb, Sb, Bi, La, Ce, etc. are dissolved in barium titanate particles come into grain boundary contact 4 to form secondary particles 2. Each secondary particle 2 has PTCR characteristics. It is preferable that the particle size of the primary particles is 2 to 20 μm. If the particle size is 20 μm or more, the maximum resistance value above the Curie point will decrease and the PTCR effect will become small. If it is 2 μm or less, the resistance value at room temperature will be high, and the insulator The disadvantage is that it begins to exhibit characteristics.
２次粒子の粒径は10〜200μｍであることが好
ましく、10μｍ以下では２次粒子内でのPTCR効
果を与える１次粒子間の粒界の数が少なくり、大
きなPTCR効果は期待できない。 The particle size of the secondary particles is preferably 10 to 200 μm; if it is less than 10 μm, the number of grain boundaries between primary particles that provide a PTCR effect within the secondary particles is small, and a large PTCR effect cannot be expected.
また、200μｍ以上では粒体材料としての取扱
いが不便となるという欠点がある。ｎ型半導性チ
タン酸バリウムに対してオーム性の接触をする金
属とは、そのフエルミ準位が半導性チタン酸バリ
ウムのフエルミ準位より高い位置にあるものであ
り、そのような金属としてはIn，GA，Ni，Sn等
が好ましく、それらより選ばれる単独のものであ
つても、２種以上の混合物または合金であつても
よい。 Furthermore, if the particle size is 200 μm or more, it is difficult to handle it as a granular material. A metal that makes ohmic contact with n-type semiconducting barium titanate is one whose Fermi level is higher than that of semiconducting barium titanate; is preferably In, GA, Ni, Sn, etc., and may be a single material selected from these, or a mixture or alloy of two or more thereof.
オーム性の接触をする金属の半導性チタン酸バ
リウム粒体への混合割合としては５〜20重量％で
あることが好ましく、５重量％以下ではオーム性
の接触をする金属の量が少なすぎて個々の半導性
チタン酸バリウム粉末同志をその金属を介して接
触させることができず、また、20重量％以上では
オーム性の接触をする金属の量が多すぎてその金
属同志が接触連結してしまうためPTCR特性を有
する半導性チタン酸バリウムを成形することがで
きない。 The mixing ratio of the metal that makes ohmic contact with the semiconducting barium titanate particles is preferably 5 to 20% by weight, and if it is less than 5% by weight, the amount of metal that makes ohmic contact is too small. Therefore, individual semiconducting barium titanate powders cannot be brought into contact with each other through the metal, and if it exceeds 20% by weight, the amount of metal that makes ohmic contact is too large, causing the metals to contact and connect. Therefore, semiconducting barium titanate with PTCR characteristics cannot be molded.
本発明の半導性チタン酸バリウム材料は、第１
図に示すように２次粒子２である半導性チタン酸
バリウム粒体がオーム性の接触をする金属３を介
して連結され一つの大きな半導性チタン酸バリウ
ム成形体を形成するようにすることにより、大き
なPTCR効果が得られる。 The semiconductive barium titanate material of the present invention has a first
As shown in the figure, semiconducting barium titanate particles, which are secondary particles 2, are connected via a metal 3 that makes ohmic contact to form one large semiconducting barium titanate compact. By doing so, a large PTCR effect can be obtained.
本発明の半導性チタン酸バリウム材料の使用方
法としては、この半導性チタン酸バリウム材料を
溶剤によりペースト状にし基板に塗布して膜状に
したり、ローラーにより圧延してフイルム状成形
体としたり、あるいは溶剤を添加しないで圧縮し
て種々の形態に成形して用いることができる。 The semiconductive barium titanate material of the present invention can be used by making it into a paste with a solvent and applying it to a substrate to form a film, or by rolling it with a roller to form a film-like molded product. Alternatively, it can be compressed and molded into various shapes without adding a solvent.
次に本発明の実施例について説明する。 Next, examples of the present invention will be described.
実施例 １
蓚酸チタニルバリウム（BaTiO（C2O4）2・
4H2O）と半導体化不純物としてのSb2O3とを湿
式混合し、乾燥後、1300℃で１時間空気中で焼成
して半導性チタン酸バリウムとした後、粉砕し、
ふるいにより44μｍ以下、45〜74μｍ、75〜149
μｍの粒体に分離し、こられの半導性チタン酸バ
リウム粒体を出発原料とした。この粒体は、２〜
５μｍの１次粒子が複数個粒界結合した２次粒子
である。Example 1 Barium titanyl oxalate (BaTiO(C 2 O 4 ) 2 .
4H 2 O) and Sb 2 O 3 as a semiconducting impurity are wet mixed, dried and fired in air at 1300°C for 1 hour to obtain semiconductive barium titanate, which is then pulverized.
44μm or less, 45-74μm, 75-149 by sieving
The semiconducting barium titanate particles were separated into micrometer particles and used as a starting material. This granule is 2~
These are secondary particles in which a plurality of 5 μm primary particles are bonded at grain boundaries.
これらの半導性チタン酸バリウム原料粒体に、
原料粒体に対し０〜20重量％のInを添加したもの
をエタノールに分散させペーストの色が均一な灰
色になるまで混合した。その後ビーカー中で約
200℃、10分間、撹拌しながら熱処理したものを
試料粒体とした。この粒体を約0.5ｇ秤取し、直
径10mm、厚み1.4〜1.8mmのペレツトに加圧成形し
た。この際プレス圧は700〜1800Kg／cm2の間で変
化させ、種々の空隙率を有するペレツトを得た。 These semiconducting barium titanate raw material particles,
A mixture of 0 to 20% by weight of In added to the raw material granules was dispersed in ethanol and mixed until the paste became uniformly gray in color. Then in the beaker about
Sample granules were heat treated at 200°C for 10 minutes with stirring. Approximately 0.5 g of this granule was weighed out and pressure-molded into pellets with a diameter of 10 mm and a thickness of 1.4 to 1.8 mm. At this time, the press pressure was varied between 700 and 1800 kg/cm 2 to obtain pellets with various porosity.
これらのペレツトの両面に電極として導電性
Agペーストを塗布し（便宜上電極に非オーム性
接触をするAgペーストを用いたが、試料表面に
は一定量のInが存在しており、In―Agの導電性
の接続によりAgペーストを用いたことによる試
料の抵抗―温度特性への影響は余り大きくないこ
とが確認されている）、Agペーストが乾燥した
後、直流２探針法により、空気中における抵抗―
温度特性を測定した。 Conductive electrodes on both sides of these pellets
Ag paste was applied (for convenience, we used Ag paste that makes non-ohmic contact with the electrode, but since a certain amount of In was present on the sample surface, we used Ag paste due to the In-Ag conductive connection. After the Ag paste has dried, the resistance in the air is measured using the DC two-probe method.
The temperature characteristics were measured.
第２図はInの重量比を変えた場合の抵抗―温度
特性を示すもので、粒径44〜74μｍの半導性チタ
ン酸バリウム粒体を用い、成形圧力700Kg／cm2と
し、Inの混合比（重量％）を０％，５％，
８％、10％，12％，15％，20％のときの
抵抗―温度特性を示す。In無添加の試料すなわ
ち、半導性チタン酸バリウム粒体のみの場合にお
いては粒体間の高い接触抵抗のために絶縁体的な
特性を示し、ある適当のInの添加量〜に対し
て顕著なPTCR効果を示し、Inの添加量が多すぎ
る場合，には金属的な特性を示すようにな
る。 Figure 2 shows the resistance-temperature characteristics when the weight ratio of In is changed. Semiconductive barium titanate particles with a particle size of 44 to 74 μm are used, the molding pressure is 700 Kg/cm 2 , and In is mixed. The ratio (weight%) is 0%, 5%,
Shows the resistance-temperature characteristics at 8%, 10%, 12%, 15%, and 20%. Samples without In added, that is, in the case of only semiconducting barium titanate particles, exhibit insulating properties due to high contact resistance between the particles, which is noticeable for a certain appropriate amount of In added. It exhibits a strong PTCR effect, and when the amount of In added is too large, it begins to exhibit metallic properties.
第３図は、半導性チタン酸バリウム粒体の粒径
の抵抗―温度特性への影響を示すもので、Inの添
加量を10重量％、成形圧力を700Kg／cm2とし、粒
径を44μｍ以下，45〜74μｍ，75〜149μ
ｍのときの抵抗―温度特性を示す。 Figure 3 shows the influence of particle size on the resistance-temperature characteristics of semiconductive barium titanate particles.The amount of In added was 10% by weight, the molding pressure was 700Kg/ cm2 , and the particle size was 44μm or less, 45~74μm, 75~149μ
The resistance-temperature characteristics when m is shown.
第４図は半導性チタン酸バリウム粒体の粒径を
45〜74μｍとし、Inの添加量を10重量％とし、加
圧成形時の圧力を700Kg／cm2，1300Kg／cm2，
1800Kg／cm2とした場合の抵抗―温度特性を示
す。成形圧力の増加にともなつて、接触抵抗が低
下し、室温での抵抗値が低下していくのがわか
る。抵抗―温度特性は半導性チタン酸バリウムの
１次粒子、および２次粒子の粒径、成形圧力等に
より変化し、Inの混合割合５〜20重量％におい
て、PTCR特性を有する成形体が得られる。 Figure 4 shows the particle size of semiconductive barium titanate particles.
45 to 74μm, the amount of In added was 10% by weight, and the pressure during pressure molding was 700Kg/cm 2 , 1300Kg/cm 2 ,
The resistance-temperature characteristics are shown when the resistance is 1800Kg/cm 2 . It can be seen that as the molding pressure increases, the contact resistance decreases, and the resistance value at room temperature decreases. The resistance-temperature characteristics vary depending on the particle size of the primary and secondary particles of semiconducting barium titanate, the molding pressure, etc., and a molded product with PTCR characteristics can be obtained at a mixing ratio of In of 5 to 20% by weight. It will be done.
実施例 ２
実施例１と同様にして得られた粒径45〜74μｍ
の半導性チタン酸バリウム粒体にIn―Ga（Inと
Gaの混合割合が１：１である）の混合物を添加
して、実施例１と同様にペレツトを成形し、抵抗
―温度特性を測定した。Example 2 Particle size 45 to 74 μm obtained in the same manner as Example 1
In--Ga (In and
A mixture of 1:1 (Ga mixture ratio: 1:1) was added, pellets were formed in the same manner as in Example 1, and the resistance-temperature characteristics were measured.
第５図は半導性チタン酸バリウム粒体にIn―
Gaの混合物（重量％）を10％，12％，15
％を添加し700Kg／cm2で圧力成形した場合の抵抗
―温度特性を示す。抵抗―温度特性は半導性チタ
ン酸バリウムの１次粒子および２次粒子の粒径、
成形圧力等により変化し、In―Gaの混合割合５
〜20重量％において、PTCR特性を有する成形体
が得られる。 Figure 5 shows In-
Mixture of Ga (wt%) 10%, 12%, 15
% and pressure molded at 700Kg/ cm2 . The resistance-temperature characteristics are determined by the particle size of the primary and secondary particles of semiconducting barium titanate,
The In-Ga mixing ratio varies depending on molding pressure, etc.
At ~20% by weight, molded bodies with PTCR properties are obtained.
焼成過程を必要としないで大きなPTCR特性の
半導性チタン酸製品が得られるので、基板との反
応に問題がなく、樹脂等の種々の基板を用いて、
膜状の半導性チタン酸バリウムを形成し自己制御
型発熱体等として床材、壁材等の保温体に用いる
ことができるという著効を有するものである。 Semiconducting titanate products with large PTCR characteristics can be obtained without the need for a firing process, so there is no problem with reaction with substrates, and various substrates such as resin can be used.
It has the remarkable effect of forming semiconductive barium titanate in the form of a film and being able to be used as a self-regulating heating element for heat insulators such as flooring and wall materials.
第１図は本発明の半導性チタン酸バリウム材料
の構成を示す図、第２図はInの重量比を変えた場
合の抵抗―温度特性を示す図、第３図は半導性チ
タン酸バリウム粒体の粒径を変えた場合の抵抗―
温度特性を示す図、第４図は加圧成形圧力を変え
た場合の抵抗―温度特性を示す図、第５図はIn―
Gaの重量比を変えて場合の抵抗―温度特性を示
す図である。
図中、１……１次粒子、２……２次粒子、３…
…オーム性の接触をする金属、４……粒界接触。
Figure 1 is a diagram showing the composition of the semiconducting barium titanate material of the present invention, Figure 2 is a diagram showing the resistance-temperature characteristics when the weight ratio of In is changed, and Figure 3 is a diagram showing the structure of the semiconducting barium titanate material of the present invention. Resistance when changing the particle size of barium particles
Figure 4 is a diagram showing the temperature characteristics, Figure 4 is a diagram showing the resistance-temperature characteristics when the pressure molding pressure is changed, Figure 5 is In-
FIG. 4 is a diagram showing resistance-temperature characteristics when the weight ratio of Ga is changed. In the figure, 1... primary particles, 2... secondary particles, 3...
...Metal with ohmic contact, 4...Grain boundary contact.
Claims (1)
界結合した粒径10〜200μｍの半導性チタン酸バ
リウム粒体に、オーム性の接触をする金属を５〜
20重量％添加混合し、前記半導性チタン酸バリウ
ム粒体を前記オーム性の接触をする金属を介して
連結した二次焼成を必要としない半導性チタン酸
バリウム材料。1. A metal that makes ohmic contact is applied to semiconductive barium titanate grains with a grain size of 10 to 200 μm, in which a plurality of uniform primary particles with a grain size of 2 to 20 μm are bonded at grain boundaries.
A semiconductive barium titanate material which does not require secondary firing, in which 20% by weight is added and mixed and the semiconductive barium titanate particles are connected via the metal that makes ohmic contact.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP56214551A JPS58116702A (en) | 1981-12-29 | 1981-12-29 | Semiconductive barium titanate material |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP56214551A JPS58116702A (en) | 1981-12-29 | 1981-12-29 | Semiconductive barium titanate material |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS58116702A JPS58116702A (en) | 1983-07-12 |
| JPS622682B2 true JPS622682B2 (en) | 1987-01-21 |
Family
ID=16657600
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP56214551A Granted JPS58116702A (en) | 1981-12-29 | 1981-12-29 | Semiconductive barium titanate material |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS58116702A (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS593901A (en) * | 1982-06-29 | 1984-01-10 | 株式会社井上ジャパックス研究所 | Resistance varying material by temperature |
| WO2013065373A1 (en) * | 2011-11-01 | 2013-05-10 | 株式会社村田製作所 | Semiconductor ceramic, and ptc thermistor using same |
-
1981
- 1981-12-29 JP JP56214551A patent/JPS58116702A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS58116702A (en) | 1983-07-12 |
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