JP2754647B2 - Manufacturing method of electrode material - Google Patents
Manufacturing method of electrode materialInfo
- Publication number
- JP2754647B2 JP2754647B2 JP380689A JP380689A JP2754647B2 JP 2754647 B2 JP2754647 B2 JP 2754647B2 JP 380689 A JP380689 A JP 380689A JP 380689 A JP380689 A JP 380689A JP 2754647 B2 JP2754647 B2 JP 2754647B2
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- Prior art keywords
- electrode
- ceramic
- present
- electrode material
- discharge
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Description
【発明の詳細な説明】 （産業上の利用分野） 本発明は放電電極に関し、特にその電極の製造方法に
関する。Description: TECHNICAL FIELD The present invention relates to a discharge electrode, and more particularly to a method for manufacturing the electrode.
（従来の技術） 蛍光燈などの放電燈の電極材料としては、従来、タン
グステンなどの金属が用いられている。しかし、この場
合は、予熱の必要があること、エミッションが少なく管
電圧が高いこと、再点弧電圧が高いことといった欠点が
ある。(Prior Art) Conventionally, metals such as tungsten have been used as electrode materials for discharge lamps such as fluorescent lamps. However, in this case, there are disadvantages such as necessity of preheating, low emission, high tube voltage, and high restrike voltage.
一方、BaTiO3などのセラミックスを還元処理により半
導体化したセラミック放電電極も提案されているが（例
えばUSP 2686274）、従来のものは、熱衝撃に弱い，水
銀粒子によるイオンスパッタリングにより劣化しやす
い，電流密度が小さい，といった欠点がある。On the other hand, ceramic discharge electrodes in which ceramics such as BaTiO 3 are converted into semiconductors by reduction treatment have also been proposed (for example, US Pat. No. 2,686,274). However, conventional electrodes are weak to thermal shock, easily deteriorated by ion sputtering by mercury particles, There is a disadvantage that the density is low.
（発明が解決しようとする課題） 従って、本発明は従来の技術の上記欠点を改善し、予
熱の必要がなく、エミッションが良好で管電圧及び再点
弧電圧が低く、熱衝撃に強く、電流密度の大きな放電電
極を提供することを目的とする。Accordingly, the present invention overcomes the above disadvantages of the prior art, eliminates the need for preheating, provides good emissions, has low tube and reignition voltages, is resistant to thermal shock, An object is to provide a discharge electrode having a high density.
（課題を解決するための手段） 前記目的を達成するための本発明の特徴は、Ba,Sr,Ca
から選択される第１の材料と、Ti,Zrから選択される第
２の材料と、Ta,V,Mo,Ru,Rh,Hf,W,Re,Os,Ir,Nbから選択
される第３の材料の各酸化物を原料としてセラミックス
を生成する工程と、該セラミックスを還元性ガスの雰囲
気中で還元する還元工程とを有する電極材料の製造方法
にある。(Means for Solving the Problems) The feature of the present invention for achieving the above object is that of Ba, Sr, Ca
A first material selected from Ti, Zr, and a third material selected from Ta, V, Mo, Ru, Rh, Hf, W, Re, Os, Ir, and Nb. The present invention relates to a method for producing an electrode material, comprising: a step of producing ceramics using each oxide of the above material as a raw material; and a reduction step of reducing the ceramics in an atmosphere of a reducing gas.
（作用） 上述の還元工程の際、セラミックスの半導体化と共
に、表面にイオンスパッタリングに強い保護膜が形成さ
れる。半導体化されたセラミックス自体は電子放出特性
が優れているので、電子放出特性に優れ、かつ、イオン
スパッタリングに強い放電電極が得られる。(Operation) In the above-described reduction step, a protective film that is resistant to ion sputtering is formed on the surface of the ceramic as well as turning the ceramic into a semiconductor. Since the semiconductor ceramic itself has excellent electron emission characteristics, a discharge electrode having excellent electron emission characteristics and strong against ion sputtering can be obtained.
（実施例） 第１図は本発明による放電電極の構造を示し、細長の
ガラス管100の端部に、放電電極10が、ほぼＵ字形の腕2
0を有する導体リード（例えばタングステン製）により
保持される。放電電極10は、ほぼ円筒型のセラミック母
体12と、その表面に付着される保護膜16と、円筒の一面
にもうけられる非貫通の孔部14とを有する。孔部14の内
部には保護膜16は設けられないものとする。なお、好ま
しくは導体リード20により保持するために、該リード20
と結合する細長の溝16a,16bを円筒の側面に円筒の軸方
向にもうける（第２図）。(Embodiment) FIG. 1 shows the structure of a discharge electrode according to the present invention, in which a discharge electrode 10 is provided at the end of an elongated glass tube 100 with a substantially U-shaped arm 2.
It is held by a conductor lead having zero (for example, made of tungsten). The discharge electrode 10 has a substantially cylindrical ceramic base 12, a protective film 16 attached to the surface thereof, and a non-penetrating hole 14 formed on one surface of the cylinder. It is assumed that the protective film 16 is not provided inside the hole 14. In addition, preferably, the lead 20
Elongated grooves 16a and 16b are formed on the side surface of the cylinder in the axial direction of the cylinder (FIG. 2).
上記構造において、セラミック母体12は還元処理によ
り半導体化されたセラミックスで、例えばBaTiO3であ
る。In the above structure, the ceramic matrix 12 is a ceramic converted into a semiconductor by a reduction treatment, for example, BaTiO 3 .
保護膜16は還元処理の際表面に構成される表面析出層
で、それ自身のエミッション作用は小さいが、水銀イオ
ンなどのスパッタリングに強い性質を有する。The protective film 16 is a surface deposition layer formed on the surface during the reduction treatment, and has a small emission effect by itself, but has a strong property against sputtering of mercury ions and the like.
孔部14はセラミックス母体12が露出し、この部分から
電子が放電される。The hole 14 exposes the ceramic base 12, from which electrons are discharged.
電極は第１図に示すごとく、保護膜16がイオンの到来
方向（対向電極の方向）を向い、孔部14はイオンの到来
方向と反対側を向くように配置される。As shown in FIG. 1, the electrodes are arranged such that the protective film 16 faces the direction of arrival of ions (the direction of the counter electrode), and the holes 14 face the side opposite to the direction of arrival of ions.
図示の構造において、セラミックス母体12はエミッシ
ョン（電子放出）特性に優れ、孔部14から豊富な電子を
放出し、該電子は矢印Ａにそって移動し、公知の理論に
従って放電燈の放電に寄与する。一方、放電に伴って発
生するガスイオン（例えばHgイオン）は図の矢印の方向
（対向電極の方向）から電極に到来し、保護膜16に衝突
する。このとき、孔部14はイオンの方向Ｂからみて陰に
位置するので、孔部自体はイオンスパッタリングにより
容易に劣化するものであるが、イオンが直接孔部14に衝
突することはなく、従って、孔部14の表面がイオンスパ
ッタリング12より劣化することはない。In the structure shown in the figure, the ceramic matrix 12 has excellent emission (electron emission) characteristics, emits abundant electrons from the holes 14, and the electrons move along the arrow A and contribute to the discharge of the discharge lamp according to a known theory. I do. On the other hand, gas ions (for example, Hg ions) generated by the discharge arrive at the electrodes from the direction of the arrow in the figure (the direction of the counter electrode) and collide with the protective film 16. At this time, since the hole 14 is located in the shadow when viewed from the direction B of the ions, the hole itself is easily deteriorated by ion sputtering, but the ions do not directly collide with the hole 14, and therefore, The surface of the hole 14 does not deteriorate more than the ion sputtering 12.
以上のごとき構造により、豊富な電子放出と、イオン
スパッタリングに対する保護とを同時に実現することが
できる。With the above structure, abundant electron emission and protection against ion sputtering can be simultaneously realized.
次にセラミックス母体10の組成及び製造方法について
のべる。セラミックス母体10の組成はXA（YyZx）BO3の
構造のセラミックスで、Ｘの部分はBa,Sr,Caから選択さ
れる１種以上の元素が可能であり、Ｙの部分は、Zr,Ti
から選択される１種以上の元素であり、Ｚの部分は、T
a,V,Mo,Ru,Rh,Hf,W,Re,Os,Ir,Nbから選択される１種以
上の元素である。Ｚの部分の代表的物質は５価の金属又
は融点が1800℃以上の物質である。Next, the composition and manufacturing method of the ceramic base 10 will be described. The composition of the ceramic matrix 10 is a ceramic having a structure of X A (Y y Z x ) B O 3 , where X is at least one element selected from Ba, Sr, and Ca, and Y is , Zr, Ti
At least one element selected from the group consisting of
a, V, Mo, Ru, Rh, Hf, W, Re, Os, Ir, Nb. A typical substance in the Z portion is a pentavalent metal or a substance having a melting point of 1800 ° C. or more.
好ましい実施例によると、Ｘ＝Ba,Y＝Zr,Z＝Nbで、各
々、BaO,ZrO2，Nb2O5の形で提供され、BaOとZrO2とNb2O
5の原料のモル比は、（0.5〜1.5）：（0.3〜0.7）：
（0.3〜0.7）である。上記モル比の更に好ましい実施例
は、1:0.6:0.4又は1:0.6:0.2である。According to a preferred embodiment, X = Ba, Y = Zr, Z = Nb, each provided in the form of BaO, ZrO 2 , Nb 2 O 5 , wherein BaO, ZrO 2 and Nb 2 O
The molar ratio of the raw materials of 5 is (0.5-1.5) :( 0.3-0.7):
(0.3 to 0.7). More preferred embodiments of the above molar ratio are 1: 0.6: 0.4 or 1: 0.6: 0.2.
第３図はセラミックス母体10の製造方法を示し、工程
20で材料（ペロブスカイト型酸化物（例えばBaO）と、
チタン又はジルコン酸塩（例えばZrO2）と、Nb2O5）を
混合する。工程22は通常のセラミックスの製造工程と同
じで、混合、仮焼き、微砕粉、顆粒化、バインダを混合
して成型の各工程をふくむ。工程24では1300℃〜1800℃
の空気中（より好ましくは約1500℃の酸素雰囲気中）で
約２時間の焼成を行なうが、この工程は後の還元処理工
程26との関係で省略することも可能である。FIG. 3 shows a method of manufacturing the ceramic base 10 and includes steps
20 with materials (perovskite oxide (eg BaO)
Titanium or zirconate (for example, ZrO 2 ) and Nb 2 O 5 ) are mixed. Step 22 is the same as a normal ceramics manufacturing step, and includes the steps of mixing, calcining, pulverizing powder, granulating, and blending a binder. 1300 ℃ ~ 1800 ℃ in process 24
The calcination is performed for about 2 hours in the air (preferably in an oxygen atmosphere at about 1500 ° C.), but this step can be omitted in connection with the subsequent reduction treatment step 26.
還元処理26は本発明の重要な特徴で、1300℃〜1600℃
の還元性ガス（例えば水素（H2））雰囲気中で約２時間
の還元処理を行なう。還元処理の条件は温度が1300℃〜
1600℃でより好ましくは1450℃、雰囲気は水素をふくむ
窒素（アルゴンをふくんでもよい）で、好ましくは水素
と窒素の混合気を120l/hの割合で、水素9.6l/h（水素濃
度８％）となるごとく調節する。Reduction treatment 26 is an important feature of the present invention,
In a reducing gas (eg, hydrogen (H 2 )) atmosphere for about 2 hours. Conditions for the reduction treatment are as follows:
The temperature is preferably 1600 ° C., more preferably 1450 ° C., and the atmosphere is nitrogen containing hydrogen (or argon may be contained). Preferably, a mixture of hydrogen and nitrogen is supplied at a rate of 120 l / h to 9.6 l / h of hydrogen (hydrogen concentration 8%). %).
還元処理の結果、セラミックスは半導体化されると共
に、表面に保護膜16として作用するNbNO膜が２〜３μｍ
の厚さで付着する。As a result of the reduction treatment, the ceramic is turned into a semiconductor, and the NbNO film acting as a protective film 16 on the surface is formed to have a thickness of 2 to 3 μm.
Adheres with a thickness of
なお、保護膜の存在しない非貫通の孔部14は還元処理
の後、ドリルでもうけるか、又は孔部をふくめて保護膜
を付着させた後、孔部の保護膜を除去する。After the reduction treatment, the non-penetrating holes 14 where no protective film is present are drilled, or the protective film is adhered by covering the holes, and then the protective film of the holes is removed.
次に本発明による電極の実験結果についてのべる。 Next, experimental results of the electrode according to the present invention will be described.
第４図は、管電圧及び再点弧電圧に関する実験結果
で、周波数50Hz、管電流100mA（RMS）の条件で実験した
もので、Ａは本発明による電極、Ｂは従来のセラミック
ス（BaTiO3）電極、Ｃは従来の金属（Ni）電極、Ｄは従
来の金属（Ｗ）電極の特性を示す。各図でほぼ矩形の曲
線Ａは管電圧を示し、（Ａ），（Ｂ）及び（Ｄ）は100V
/目盛、（Ｃ）は200V/目盛である。ほぼ正弦波状の曲線
Ｂは管電流を示し、各図共70mA/目盛で、実効値が100mA
となっている。FIG. 4 shows the results of experiments on the tube voltage and the re-ignition voltage, which were conducted under the conditions of a frequency of 50 Hz and a tube current of 100 mA (RMS). A is an electrode according to the present invention, and B is a conventional ceramic (BaTiO 3 ). The electrode, C indicates the characteristics of the conventional metal (Ni) electrode, and D indicates the characteristics of the conventional metal (W) electrode. In each figure, a substantially rectangular curve A indicates the tube voltage, and (A), (B) and (D) indicate 100 V
/ Scale, (C) is 200V / scale. A substantially sinusoidal curve B shows the tube current, and each drawing has a 70 mA / scale and an effective value of 100 mA.
It has become.
第４図（Ａ）から本発明による電極は管電圧が約60
V、再点弧電圧が約150Vで、これらの値は第４図（Ｂ）
の従来のセラミックス電極（管電圧60〜80V、再点弧電
圧150V）に比べて見劣りしない。つまり、本発明による
電極の電子放出特性は従来のセラミックス電極と同等以
上である。第４図（Ｃ）のニッケル電極では管電圧250
V、再点弧電圧440Vであり、又第４図（Ｄ）のタングス
テン電極では管電圧80V、再点弧電圧230Vであり、従っ
て、本発明の材料は従来の金属電極（ニッケル、タング
ステン）より電子放出特性が優れている。FIG. 4 (A) shows that the electrode according to the present invention has a tube voltage of about 60.
V, the re-ignition voltage is about 150V. These values are shown in Fig. 4 (B).
It is not inferior to conventional ceramic electrodes (tube voltage 60-80V, restrike voltage 150V). That is, the electron emission characteristics of the electrode according to the present invention are equal to or higher than those of the conventional ceramic electrode. The tube voltage of the nickel electrode shown in FIG.
V, the re-ignition voltage is 440 V, and the tungsten electrode shown in FIG. 4 (D) has a tube voltage of 80 V and a re-ignition voltage of 230 V. Therefore, the material of the present invention is different from the conventional metal electrodes (nickel, tungsten). Excellent electron emission characteristics.
第５図は本発明と従来のセラミックス電極の熱衝撃試
験の実験結果を示す図で、（Ａ）は従来のセラミックス
電極で還元処理を行なわないもの、（Ｂ）は従来のセラ
ミックス電極で還元処理を行ったもの、（Ｃ）は本発明
による電極の特性を示す。5A and 5B show the results of a thermal shock test of the present invention and a conventional ceramic electrode, wherein FIG. 5A shows a conventional ceramic electrode without a reduction treatment, and FIG. 5B shows a reduction treatment with a conventional ceramic electrode. (C) shows the characteristics of the electrode according to the present invention.
各図で横軸は温度差（炉で加熱した温度と冷却水の温
度との差）であり、たて軸は抗折強度（３点曲げ試験）
を示す。図の（Ａ）及び（Ｂ）では温度差が100℃付近
から特性が劣化するのに対し、図の（Ｃ）（本発明）で
は温度差が250℃付近まで良好な特性が得られることが
わかる。従って、本発明による電極材料はイオンスパッ
タリングによっても劣化しない。In each figure, the horizontal axis is the temperature difference (difference between the temperature heated in the furnace and the temperature of the cooling water), and the vertical axis is the bending strength (3-point bending test).
Is shown. In the figures (A) and (B), the characteristics deteriorate when the temperature difference is around 100 ° C., whereas in the case of FIG. (C) (the present invention), good characteristics can be obtained up to the temperature difference of about 250 ° C. Recognize. Therefore, the electrode material according to the present invention does not deteriorate even by ion sputtering.
（発明の効果） 以上説明したごとく、本発明による電極は、従来の金
属電極と比較して、エミッションが良好で管電圧及び再
点弧電圧が低く、従って、予熱の不要な放電燈を得るこ
とができる。又、エミッションが良好なことから管径の
細い放電燈を得ることができる。又、従来のセラミック
ス電極と比較して熱衝撃に強く、イオンスパッタリング
で破損しない電極を得ることができ、又、Irms＝100mA
程度のアーク放電にも耐えることができる。(Effects of the Invention) As described above, the electrode according to the present invention has better emission, lower tube voltage and lower re-ignition voltage as compared with the conventional metal electrode, and therefore can obtain a discharge lamp which does not require preheating. Can be. In addition, a discharge lamp having a small tube diameter can be obtained because of good emission. In addition, compared to conventional ceramic electrodes, it is possible to obtain an electrode that is more resistant to thermal shock and that is not damaged by ion sputtering. Also, I rms = 100 mA
It can withstand some degree of arc discharge.
第１図は本発明による放電電極の構造例、第２図は本発
明によるセラミックス母体の拡大図、第３図は本発明に
よる電極の製造工程を示す図、第４図は本発明による電
極の実験結果を従来の電極の特性と共に示す図、第５図
は本発明による電極の熱衝撃試験の実験結果を従来の電
極の特性と共に示す図である。 10;放電電極、12;セラミックス母体 14;孔部、16;保護膜 16a,16b;溝、20;導体リード 100;ガラス管FIG. 1 is a structural example of a discharge electrode according to the present invention, FIG. 2 is an enlarged view of a ceramic matrix according to the present invention, FIG. 3 is a view showing a manufacturing process of the electrode according to the present invention, and FIG. FIG. 5 shows the experimental results together with the characteristics of the conventional electrode, and FIG. 5 shows the experimental results of the thermal shock test of the electrode according to the present invention together with the characteristics of the conventional electrode. 10; discharge electrode, 12; ceramic matrix 14; hole, 16; protective film 16a, 16b; groove, 20; conductor lead 100; glass tube
───────────────────────────────────────────────────── フロントページの続き (72)発明者 田口 春男 東京都中央区日本橋１丁目13番１号 テ ィーディーケイ株式会社内 (72)発明者 福田 勝 東京都中央区日本橋１丁目13番１号 テ ィーディーケイ株式会社内 (56)参考文献 特開 昭55−46413（ＪＰ，Ａ) 特開 昭55−49833（ＪＰ，Ａ) 特開 平２−186550（ＪＰ，Ａ) 特開 昭54−22972（ＪＰ，Ａ) 特開 昭58−220347（ＪＰ，Ａ) ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Haruo Taguchi 1-13-1 Nihonbashi, Chuo-ku, Tokyo TDK Corporation (72) Inventor Masaru Fukuda 1-13-1 Nihonbashi, Chuo-ku, Tokyo TDK (56) References JP-A-55-46413 (JP, A) JP-A-55-49833 (JP, A) JP-A-2-186550 (JP, A) JP-A-54-22972 (JP, A) A) JP-A-58-220347 (JP, A)
Claims (5)
材料の各酸化物を原料としてセラミックスを生成する工
程と、 該セラミックスを還元性ガスの雰囲気中で還元する還元
工程とを有することを特徴とする電極材料の製造方法。1. A first material selected from Ba, Sr, Ca, a second material selected from Ti, Zr, Ta, V, Mo, Ru, Rh, Hf, W, Re, Os An electrode material comprising: a step of producing ceramics using each oxide of a third material selected from the group consisting of, Ir and Nb as a raw material; and a reducing step of reducing the ceramics in an atmosphere of a reducing gas. Manufacturing method.
なわれることを特徴とする請求項１記載の電極材料の製
造方法。2. The method for producing an electrode material according to claim 1, wherein said reduction step is performed at a temperature of 1300 ° C. to 1600 ° C.
を特徴とする請求項１記載の電極材料の製造方法。3. The method for producing an electrode material according to claim 1, wherein said reducing gas contains hydrogen and nitrogen.
を特徴とする請求項３記載の電極材料の製造方法。4. The method for producing an electrode material according to claim 3, wherein said reducing gas includes an inert gas.
徴とする請求項３記載の電極材料の製造方法。5. The method according to claim 3, wherein said inert gas is argon.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP380689A JP2754647B2 (en) | 1989-01-12 | 1989-01-12 | Manufacturing method of electrode material |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP380689A JP2754647B2 (en) | 1989-01-12 | 1989-01-12 | Manufacturing method of electrode material |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH02186527A JPH02186527A (en) | 1990-07-20 |
| JP2754647B2 true JP2754647B2 (en) | 1998-05-20 |
Family
ID=11567437
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP380689A Expired - Lifetime JP2754647B2 (en) | 1989-01-12 | 1989-01-12 | Manufacturing method of electrode material |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2754647B2 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6383416B1 (en) | 1999-03-12 | 2002-05-07 | Tdk Corporation | Electron-emitting material and preparing process |
| US6432325B1 (en) | 1999-03-19 | 2002-08-13 | Tdk Corporation | Electrode |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH02215039A (en) * | 1989-02-15 | 1990-08-28 | Mitsubishi Electric Corp | Discharge electrode |
| TW270211B (en) * | 1993-03-17 | 1996-02-11 | Tdk Electronics Co Ltd | |
| JPH103879A (en) * | 1996-06-12 | 1998-01-06 | Tdk Corp | Ceramic cathode fluorescent lamp |
-
1989
- 1989-01-12 JP JP380689A patent/JP2754647B2/en not_active Expired - Lifetime
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6383416B1 (en) | 1999-03-12 | 2002-05-07 | Tdk Corporation | Electron-emitting material and preparing process |
| US6432325B1 (en) | 1999-03-19 | 2002-08-13 | Tdk Corporation | Electrode |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH02186527A (en) | 1990-07-20 |
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