JPS6216490B2 - - Google Patents
Info
- Publication number
- JPS6216490B2 JPS6216490B2 JP9457178A JP9457178A JPS6216490B2 JP S6216490 B2 JPS6216490 B2 JP S6216490B2 JP 9457178 A JP9457178 A JP 9457178A JP 9457178 A JP9457178 A JP 9457178A JP S6216490 B2 JPS6216490 B2 JP S6216490B2
- Authority
- JP
- Japan
- Prior art keywords
- oxide
- metal
- cathode
- base metal
- coating layer
- 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
- 239000010953 base metal Substances 0.000 claims description 45
- 229910052751 metal Inorganic materials 0.000 claims description 39
- 239000002184 metal Substances 0.000 claims description 39
- 239000011247 coating layer Substances 0.000 claims description 37
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 32
- 229910052799 carbon Inorganic materials 0.000 claims description 32
- 238000002844 melting Methods 0.000 claims description 17
- 230000008018 melting Effects 0.000 claims description 11
- 229910052759 nickel Inorganic materials 0.000 claims description 11
- 229910017709 Ni Co Inorganic materials 0.000 claims description 7
- 229910003267 Ni-Co Inorganic materials 0.000 claims description 7
- 229910003262 Ni‐Co Inorganic materials 0.000 claims description 7
- 239000000956 alloy Substances 0.000 claims description 7
- 229910045601 alloy Inorganic materials 0.000 claims description 7
- 238000000151 deposition Methods 0.000 claims description 5
- 238000000034 method Methods 0.000 claims description 5
- 229910000287 alkaline earth metal oxide Inorganic materials 0.000 claims description 4
- 229910052776 Thorium Inorganic materials 0.000 claims description 3
- 229910052782 aluminium Inorganic materials 0.000 claims description 3
- 229910052804 chromium Inorganic materials 0.000 claims description 3
- 229910052749 magnesium Inorganic materials 0.000 claims description 3
- 229910052758 niobium Inorganic materials 0.000 claims description 3
- 229910052710 silicon Inorganic materials 0.000 claims description 3
- 229910052726 zirconium Inorganic materials 0.000 claims description 3
- 229910052770 Uranium Inorganic materials 0.000 claims 1
- 230000003647 oxidation Effects 0.000 claims 1
- 238000007254 oxidation reaction Methods 0.000 claims 1
- 239000010410 layer Substances 0.000 description 21
- 238000006243 chemical reaction Methods 0.000 description 9
- 229910052784 alkaline earth metal Inorganic materials 0.000 description 6
- -1 alkaline earth metal carbonate Chemical class 0.000 description 6
- 238000010406 interfacial reaction Methods 0.000 description 6
- 229910052721 tungsten Inorganic materials 0.000 description 6
- 238000004519 manufacturing process Methods 0.000 description 5
- 229910052750 molybdenum Inorganic materials 0.000 description 5
- 230000005855 radiation Effects 0.000 description 5
- 229910052702 rhenium Inorganic materials 0.000 description 5
- 230000006866 deterioration Effects 0.000 description 4
- 230000000694 effects Effects 0.000 description 4
- 239000000203 mixture Substances 0.000 description 4
- 239000000843 powder Substances 0.000 description 4
- 229910052715 tantalum Inorganic materials 0.000 description 4
- 238000007796 conventional method Methods 0.000 description 3
- 150000002739 metals Chemical class 0.000 description 3
- 239000007795 chemical reaction product Substances 0.000 description 2
- 230000007423 decrease Effects 0.000 description 2
- 238000007733 ion plating Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 238000007738 vacuum evaporation Methods 0.000 description 2
- 239000004215 Carbon black (E152) Substances 0.000 description 1
- BVKZGUZCCUSVTD-UHFFFAOYSA-L Carbonate Chemical compound [O-]C([O-])=O BVKZGUZCCUSVTD-UHFFFAOYSA-L 0.000 description 1
- 229910003296 Ni-Mo Inorganic materials 0.000 description 1
- 150000001342 alkaline earth metals Chemical group 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 238000000354 decomposition reaction Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000008034 disappearance Effects 0.000 description 1
- 238000001704 evaporation Methods 0.000 description 1
- 230000008020 evaporation Effects 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 229930195733 hydrocarbon Natural products 0.000 description 1
- 150000002430 hydrocarbons Chemical class 0.000 description 1
- 229910044991 metal oxide Inorganic materials 0.000 description 1
- 150000004706 metal oxides Chemical class 0.000 description 1
- DDTIGTPWGISMKL-UHFFFAOYSA-N molybdenum nickel Chemical compound [Ni].[Mo] DDTIGTPWGISMKL-UHFFFAOYSA-N 0.000 description 1
- 230000009257 reactivity Effects 0.000 description 1
- 238000004544 sputter deposition Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000005979 thermal decomposition reaction Methods 0.000 description 1
- 238000001771 vacuum deposition Methods 0.000 description 1
Landscapes
- Solid Thermionic Cathode (AREA)
Description
本発明は電子管用酸化物陰極に関するもので、
特に、Ｗ、Mo、Re、Taなどの高融点金属を含む
合金を基体金属とする酸化物陰極に関するもので
ある。
最近、酸化物陰極を備えた電子管において、電
源スイツチを投入後、電子放射が起こるまでの時
間を短縮させる目的で、陰極の熱容量を減少させ
るために基体金属板の板厚を薄くしたものを用い
たり、あるいは基体金属に直接通電加熱する、い
わゆる直熱方式の陰極を用いることが検討されて
いる。これらの場合、基体金属は、従来より大き
な高温強度を有することが必要となり、従来にお
けるような、Niに微量の還元性元素を含む基体
金属にかわつて、Ｗ、Mo、Re、Taなどの高融点
金属を含む合金が基体金属として用いられてい
る。この場合、高融点金属の含有量は２重量％以
上であることが必要で、これより少ないと所望の
高温強度を得ることが困難である。ところが、こ
のような高融点金属は、Niに微量の還元性元素
を含有させたものにくらべて酸化しやすい特性を
有している。このような理由から、高融点金属を
含む合金を基体金属とした酸化物陰極を、従来の
通常の製造方法で製作すると、基体金属中の高融
点金属が酸化し、この高融点金属酸化物と、基体
金属上の陰極用酸化物であるアルカリ土類金属酸
化物、あるいは、陰極用酸化物生成用のアルカリ
土類金属炭酸塩との界面に急激な反応が起こる。
そして、この界面反応の反応速度、反応生成物量
は、従来のNiに微量の還元性元素を含む基体金
属とアルカリ土類金属酸化物（以下、オキサイド
と略称する）などとの反応にくらべると比較にな
らないほど大きいものである。このように、基体
金属とオキサイドなどの間に多量の界面反応が起
こると、基体金属とオキサイドとの接触状況が大
幅に変化し、オキサイドが基体金属から剥離した
り、あるいは、オキサイドと基体金属の接触が不
十分となつて、そのため、陰極動作中のオキサイ
ド層の温度が降下するなどして、オキサイドの電
子放射量が低下し、陰極として全く実用にならな
くなるといつた欠点を有していたものである。
本発明の目的は、上記のような高融点金属より
なる基体金属を用いた酸化物陰極における欠点を
除去し、オキサイドと高融点金属よりなる基体金
属間の界面反応を抑制し、電子放射寿命を長期間
にわたつて維持できるようにした酸化物陰極を提
供するにある。
上記の目的を達成するための本発明による酸化
物陰極の特徴とするところは、少なくとも１種類
の高融点金属を２重量％以上含む合金からなる基
体金属板上に、電子放射性アルカリ土類金属酸化
物を被着形成してなる酸化物陰極において、前記
基体金属板の前記酸化物を被着する被着面は、基
体金属板上に被着形成された炭素被膜層の上面
に、Ni、Co、Ni―Coのいずれかの金属被膜層が
被着形成されてなるものである。この場合高融点
金属はＷ、Mo、Re、Taなどであつて、基体金属
は、好ましくはNi、および、Zr、Al、Mg、Si、
Ti、Ｕ、Cr、Nb、Thのような還元性元素の１種
類以上を含むものにして、炭素被膜層の厚さは、
好ましくは、50〜1000Åであつて、Ni、Co、Ni
―Coのいずれかの金属被膜の厚さは好ましく
は、100〜10000Åであるものである。このよう
な、炭素被膜層を基体金属上に被着形成して、そ
の炭素被膜層上にNi、Co、Ni―Coのいずれかの
金属被膜層を被着形成することにより、酸化物陰
極の製造工程において生じるオキサイドと基体金
属間の界面反応は抑制されるものである。
以下、図面により本発明を更に具体的に詳細に
説明する。
第１図は本発明による酸化物陰極の要部断面図
を示したものである。第１図において、符号１は
Ｗ、Mo、Re、Taなどの高融点金属の少なくとも
１種類を２重量％以上と、Zr、Al、Mg、Si、
Ti、Ｕ、Cr、Nb、Thなどの還元性元素の少なく
とも１種類を含み、残部Niである合金よりなる
基体金属板である。符号２は基体金属板１上に被
着させた厚さ50〜1000Åの炭素被膜層である。符
号３は炭素被膜層２上に被着させた厚さ100〜
10000ÅのNi、Co、Ni―Coのいずれかの金属被膜
層であり、さらにこの上に通常の方法でオキサイ
ド４を被着形成して酸化物陰極が構成されてい
る。このような構造の酸化物陰極において、炭素
被膜層２は基体金属の酸化を防止し、基体金属中
の高融点金属や還元性元素とオキサイドとの反応
を抑制する。また、Ni、Co、またはNi―Coなど
の金属被膜層３は、アルカリ土類金属炭酸塩やオ
キサイドとの反応性が小さく、それによりアルカ
リ土類金属炭酸塩を分解してオキサイドとする工
程中に発生するCO2ガスなどによつて炭素被膜層
２が酸化されて消滅するのを防止し、しかも、そ
れ自身は陰極の電子放射能に悪影響を及ぼさない
ものである。この場合、炭素被膜層２の厚さが50
Åより小では、酸化物陰極製造時に基体金属中の
高融点金属や還元性元素が容易に金属被膜層３の
表面まで拡散し、これらとアルカリ土類金属炭酸
塩、オキサイドとの反応を十分に抑制できず、ま
た、この炭素被膜層２の厚さが1000Åより大で
は、陰極動作中に炭素被膜層と基体金属との反応
が大となり、陰極として十分な動作ができなくな
るほか、この上層の金属被膜層３が剥離しやすく
なる。従つて、炭素被膜層の好ましい厚さの範囲
は50〜1000Åであり、この場合はオキサイドと基
体金属との界面反応を抑制し、また、炭素被膜層
と基体との、陰極動作中の反応を小さくさせるこ
とができる。炭素被膜層２の上に被着形成する金
属被膜層３の好ましい厚さは100〜10000Åであ
り、この膜厚が100Åより小であるとアルカリ土
類金属炭酸塩分解中の炭素被膜層の消失を防止す
る効果がうすい。また、この膜厚が10000Åより
大であると、金属被膜層が剥離しやすくなる。従
つて、金属被膜層３の好ましい厚さの範囲は100
〜10000Åであり、この場合は、酸化物陰極製造
時の炭素被膜層の消失を防し、基体金属とアルカ
リ土類金属炭酸塩、オキサイドとの反応を防止で
きるので、良好な陰極を得ることができる。
なお、Ｗ、Mo、Re、Taなどの高融点金属を含
む基体金属は、一般に基体金属からオキサイド層
が剥離しやすいので、その防止のために、基体金
属表面にNi、Ni―Co、Ni―Ｗ、Ni―Mo、Ni―Re
などの金属粉を被着し、その上面にオキサイド層
を設けることが行われているが、このような場合
においても、上記基体金属上に炭素被膜層、さら
にその上面に金属被膜層を形成した陰極では、こ
の金属粉が基体金属表面へ流出するのを防止さ
せ、金属粉と界面反応生成物の反応も防止させ
て、通常発生する金属粉の変質を防止し、陰極の
電子放射寿命を長くする効果が得られる。
以下に、本発明を試験例により説明する。
試験例 １
この試験例においては、高融点金属であるＷを
27.5重量％、還元性元素であるZrを0.4重量％、
残部はNiである合金からなる基体金属の上面
に、表１に示したような炭素被膜層を被着形成
し、その上面にNiよりなる金属被膜層を被着し
た５種類の試料Ａ、Ｂ、Ｃ、Ｄ、Ｅにつき、以後
通常の方法により酸化物陰極を製作し、カラーブ
ラウン管に実装したときの陽極最大電流の動作時
間依存性を示したのが第２図である。すなわち、
第２図においては、縦軸は陽極最大電流値の初期
値に対する割合、横軸は陰極の動作時間を示した
ものである。第２図における符号Ａ〜Ｆは、表１
The present invention relates to an oxide cathode for electron tubes,
In particular, it relates to an oxide cathode whose base metal is an alloy containing a high-melting point metal such as W, Mo, Re, or Ta. Recently, in electron tubes equipped with oxide cathodes, the thickness of the base metal plate has been reduced in order to reduce the heat capacity of the cathode in order to shorten the time from when the power switch is turned on until electron emission occurs. Alternatively, it is being considered to use a so-called direct heating type cathode in which the base metal is directly heated by electrical current. In these cases, the base metal needs to have greater high-temperature strength than conventional ones, and instead of the conventional base metal that contains Ni and a trace amount of reducing elements, high-melting point materials such as W, Mo, Re, and Ta are used. Alloys containing metals are used as base metals. In this case, the content of the high melting point metal needs to be 2% by weight or more; if it is less than this, it is difficult to obtain the desired high temperature strength. However, such a high melting point metal has the property of being easily oxidized compared to Ni containing a trace amount of a reducing element. For these reasons, if an oxide cathode using an alloy containing a high-melting point metal as the base metal is manufactured using conventional manufacturing methods, the high-melting point metal in the base metal will oxidize, and the high-melting point metal oxide and A rapid reaction occurs at the interface between the base metal and the alkaline earth metal oxide, which is the oxide for the cathode, or the alkaline earth metal carbonate for producing the oxide for the cathode.
The reaction rate and amount of reaction products of this interfacial reaction are compared to the conventional reaction between a base metal containing a small amount of reducing element in Ni and an alkaline earth metal oxide (hereinafter abbreviated as oxide). It is so large that it cannot be In this way, when a large amount of interfacial reaction occurs between the base metal and the oxide, the contact situation between the base metal and the oxide changes significantly, and the oxide may peel off from the base metal, or the oxide and the base metal may become separated. This resulted in insufficient contact, which caused the temperature of the oxide layer to drop during cathode operation, resulting in a decrease in the amount of electron emission from the oxide, making it completely useless as a cathode. It is something. The purpose of the present invention is to eliminate the drawbacks of an oxide cathode using a base metal made of a high melting point metal as described above, to suppress the interfacial reaction between the oxide and the base metal made of a high melting point metal, and to extend the electron emission life. An object of the present invention is to provide an oxide cathode that can be maintained for a long period of time. A feature of the oxide cathode according to the present invention for achieving the above object is that an electron-emitting alkaline earth metal oxide is formed on a base metal plate made of an alloy containing 2% by weight or more of at least one kind of high-melting point metal. In the oxide cathode formed by depositing a substance, the surface of the base metal plate to which the oxide is deposited has Ni, Co, on the upper surface of the carbon film layer deposited on the base metal plate. , Ni--Co metal coating layer is deposited thereon. In this case, the high melting point metal is W, Mo, Re, Ta, etc., and the base metal is preferably Ni, Zr, Al, Mg, Si,
It contains one or more reducing elements such as Ti, U, Cr, Nb, and Th, and the thickness of the carbon coating layer is as follows:
Preferably 50 to 1000 Å, Ni, Co, Ni
- The thickness of any of the Co metal coatings is preferably from 100 to 10,000 Å. By depositing such a carbon film layer on a base metal and depositing a metal film layer of Ni, Co, or Ni-Co on the carbon film layer, an oxide cathode can be formed. The interfacial reaction between the oxide and the base metal that occurs during the manufacturing process is suppressed. Hereinafter, the present invention will be explained in more concrete detail with reference to the drawings. FIG. 1 shows a sectional view of essential parts of an oxide cathode according to the present invention. In FIG. 1, numeral 1 indicates at least 2% by weight of at least one kind of high melting point metal such as W, Mo, Re, Ta, Zr, Al, Mg, Si,
The base metal plate is made of an alloy containing at least one type of reducing element such as Ti, U, Cr, Nb, and Th, and the balance being Ni. Reference numeral 2 denotes a carbon coating layer with a thickness of 50 to 1000 Å deposited on the base metal plate 1. The code 3 indicates the thickness of the carbon coating layer 2, which is 100~
This is a 10,000 Å metal film layer of either Ni, Co, or Ni-Co, and oxide 4 is further deposited thereon by a conventional method to form an oxide cathode. In the oxide cathode having such a structure, the carbon coating layer 2 prevents the base metal from being oxidized and suppresses the reaction between the high melting point metal or reducing element in the base metal and the oxide. In addition, the metal coating layer 3 such as Ni, Co, or Ni-Co has low reactivity with alkaline earth metal carbonates and oxides, and therefore during the process of decomposing alkaline earth metal carbonates to form oxides. This prevents the carbon film layer 2 from being oxidized and destroyed by CO 2 gas generated in the process, and does not itself have a negative effect on the electron radioactivity of the cathode. In this case, the thickness of the carbon coating layer 2 is 50
If it is smaller than Å, high melting point metals and reducing elements in the base metal will easily diffuse to the surface of the metal coating layer 3 during the production of the oxide cathode, and the reaction between them and the alkaline earth metal carbonate and oxide will not be sufficiently carried out. Moreover, if the thickness of the carbon film layer 2 is greater than 1000 Å, the reaction between the carbon film layer and the base metal will be large during cathode operation, and the cathode will not be able to function satisfactorily. The metal coating layer 3 is likely to peel off. Therefore, the preferable thickness range of the carbon film layer is 50 to 1000 Å, which in this case suppresses the interfacial reaction between the oxide and the base metal, and also prevents the reaction between the carbon film layer and the base material during cathode operation. It can be made smaller. The preferred thickness of the metal coating layer 3 deposited on the carbon coating layer 2 is 100 to 10,000 Å, and if this thickness is less than 100 Å, the carbon coating layer will disappear during the decomposition of the alkaline earth metal carbonate. It is not very effective in preventing. Furthermore, if the film thickness is greater than 10,000 Å, the metal coating layer is likely to peel off. Therefore, the preferred thickness range of the metal coating layer 3 is 100
~10,000 Å, and in this case, it is possible to prevent the disappearance of the carbon film layer during the production of the oxide cathode and prevent the reaction between the base metal and the alkaline earth metal carbonate or oxide, so it is possible to obtain a good cathode. can. Note that the oxide layer of base metals containing high melting point metals such as W, Mo, Re, and Ta generally tends to peel off from the base metal, so to prevent this, Ni, Ni-Co, Ni- W, Ni-Mo, Ni-Re
Although it has been done to deposit metal powder such as, and provide an oxide layer on the top surface, even in such cases, a carbon film layer is formed on the base metal, and a metal film layer is further formed on the top surface of the carbon film layer. At the cathode, this metal powder is prevented from flowing to the base metal surface, and the reaction between the metal powder and the interfacial reaction product is also prevented, thereby preventing the normally occurring deterioration of the metal powder and extending the electron emission life of the cathode. The effect of The present invention will be explained below using test examples. Test Example 1 In this test example, W, a high melting point metal, was
27.5% by weight, 0.4% by weight of Zr, a reducing element,
Five types of samples A and B were prepared, in which a carbon coating layer as shown in Table 1 was formed on the upper surface of a base metal made of an alloy with the remainder being Ni, and a metal coating layer made of Ni was deposited on the upper surface. , C, D, and E, oxide cathodes were fabricated by a conventional method, and FIG. 2 shows the dependence of the maximum anode current on the operating time when mounted on a color cathode ray tube. That is,
In FIG. 2, the vertical axis shows the ratio of the anode maximum current value to the initial value, and the horizontal axis shows the cathode operating time. The symbols A to F in FIG. 2 are shown in Table 1.
【表】
の試料Ａ〜Ｆに対応するものである。なお、この
場合、炭素被膜層は0.1TorrのCH4ガス中でイオ
ンプレーテイングによつて形成したものであり、
Ni被膜層は通常の真空蒸着法によつて形成した
ものである。
第２図から明らかなように、試料Ａのような炭
素被膜層の厚さが400Å、Ni被膜層の厚さが2000
Åであるものを用いたものは極めて優れた特性を
示し、また表１の試料Ｂ〜Ｆの組成と、第２図の
曲線Ｂ〜Ｆからわかるように、炭素被膜層および
Ni被膜層の膜厚が本発明における好ましい膜厚
から遠ざかるに従つて、動作中の電子放射量が減
少し、特に、炭素被膜層およびNi被膜層を形成
しなかつたものについての特性曲線Ｆにおいて
は、電子放射の劣化は極めて大であり、本発明の
有効性が明瞭に示されている。
試験例 ２
この試験例は、表２に示すような基体金属の組
成を有する試料Ｇ、Ｈ、Ｉ、Ｊを用いたものにつ
いてのものである。These correspond to samples A to F in [Table]. In this case, the carbon film layer was formed by ion plating in CH 4 gas at 0.1 Torr,
The Ni coating layer was formed by a normal vacuum deposition method. As is clear from Figure 2, the thickness of the carbon coating layer like Sample A is 400 Å, and the thickness of the Ni coating layer is 2000 Å.
The carbon film layer and
As the thickness of the Ni coating layer moves away from the preferred thickness in the present invention, the amount of electron radiation during operation decreases, especially in the characteristic curve F for the case where no carbon coating layer and no Ni coating layer are formed. The deterioration of electron emission was extremely large, clearly demonstrating the effectiveness of the present invention. Test Example 2 This test example uses samples G, H, I, and J having the base metal compositions shown in Table 2.
【表】
第３図は、表２に示す試料Ｇ、Ｈ、Ｉ、Ｊの４
種類の基体金属に、炭素被膜層400〜600Å、Ni
被膜層2000〜3000Åを順次形成したときの酸化物
陰極の特性を〔〕で示し、基体金属の表面に炭
素被膜層およびNi被膜層を全く形成しなかつた
ときの特性を〔〕で示し、基体金属組成の影響
を示したものである。
この場合、炭素被膜層およびNi金属被膜層の
製作方法、陰極、カラーブラウン管の製作方法
は、すべて試験例１の場合と同一である。
第３図から明らかなように、基体金属の組成が
大幅に変化しても、特性〔〕で示すように、炭
素被膜層および金属被膜層が本発明における好ま
しい厚さのものの陰極動作中の電子放射量の劣化
は極めて少ない。また特性〔〕で示すように、
本発明を適用することのない、表面二重層を有し
ない陰極は、基体金属の影響も大であり、また、
陰極動作中の電子放射量の劣化も大である。それ
に対して、本発明になる酸化物陰極においては、
基体金属の組成が多少変動しても、極めて大きな
効果が得られるものである。
なお、上記の試験例においては、炭素被膜層の
形成はCH4ガスを用いたイオンプレーテイングを
用いたが、炭素のスパーク蒸着法、炭化水素の熱
分解など、その他の通常の方法で形成してもよ
い。また、金属被膜層の形成は、Niの真空蒸着
法による例を示したが、Co、Ni―Coなどを真空
蒸着してもよく、また真空蒸着法以外の、スパツ
タ法などの通常の方法で形成してもよい。
以上の説明に明らかなように、本発明によれば
酸化物陰極において、陰極動作中の電子放射能の
劣化を防止して、長期間にわたつて電子放射量を
維持させ、電子管の品質、信頼性等を大幅に向上
させることができる極めて優れた効果が得られる
ものである。[Table] Figure 3 shows samples G, H, I, and J shown in Table 2.
Carbon coating layer 400~600Å, Ni
The properties of the oxide cathode when coating layers of 2000 to 3000 Å are sequentially formed are shown in [ ], and the properties when no carbon coating layer or Ni coating layer is formed on the surface of the base metal are shown in [ ]. This shows the influence of metal composition. In this case, the manufacturing methods of the carbon coating layer and the Ni metal coating layer, the cathode, and the color cathode ray tube were all the same as in Test Example 1. As is clear from FIG. 3, even if the composition of the base metal changes significantly, the electrons during cathode operation when the carbon coating layer and metal coating layer have the preferred thickness in the present invention, as shown in the characteristics [ ]. Deterioration of radiation amount is extremely small. Also, as shown in the characteristics [ ],
A cathode without a surface double layer, to which the present invention is not applied, is greatly influenced by the base metal, and
The amount of electron radiation during cathode operation is also significantly degraded. In contrast, in the oxide cathode of the present invention,
Even if the composition of the base metal changes slightly, a very large effect can be obtained. In the above test example, the carbon film layer was formed by ion plating using CH 4 gas, but it could also be formed by other conventional methods such as carbon spark evaporation or hydrocarbon thermal decomposition. It's okay. In addition, the metal coating layer is formed by vacuum evaporation of Ni, but it is also possible to vacuum evaporate Co, Ni-Co, etc., or by a normal method such as sputtering method other than vacuum evaporation. may be formed. As is clear from the above description, according to the present invention, in an oxide cathode, deterioration of electron radiation during cathode operation is prevented, the amount of electron radiation is maintained over a long period of time, and the quality and reliability of the electron tube is improved. This provides extremely excellent effects that can significantly improve performance and other properties.
第１図は本発明酸化物陰極の構造を示す要部断
面図である。第２図、第３図は本発明による酸化
物陰極の試験例における陽極最大電流の動作時間
依存性を、本発明によらないものと対比して示し
た特性図である。
１…基体金属板、２…炭素被膜層、３…金属被
膜層、４…オキサイド。
FIG. 1 is a sectional view of a main part showing the structure of the oxide cathode of the present invention. FIGS. 2 and 3 are characteristic diagrams showing the operating time dependence of the anode maximum current in test examples of oxide cathodes according to the present invention, in comparison with those not according to the present invention. DESCRIPTION OF SYMBOLS 1... Base metal plate, 2... Carbon coating layer, 3... Metal coating layer, 4... Oxide.
Claims (1)
重量％以上含む合金からなる基体金属板上に、電
子放射性アルカリ土類金属酸化物を被着形成して
なる酸化物陰極において、前記基体金属板の前記
酸化物を被着する被着面は、基体金属板上に被着
形成された炭素被膜層の上面にNi、Co、Ni―Co
のいずれかの金属被膜層が被着形成されてなるも
のであることを特徴とする酸化物陰極。 ２ 前記基体金属板は、Zr、Al、Mg、Si、Ti、
Ｕ、Cr、Nb、Thなどよりなる還元性元素の群中
より選ばれた少なくとも１種類とを含有してなる
ものである特許請求の範囲第１項記載の酸化物陰
極。 ３ 前記炭素被膜層の厚さは50〜1000Åであつ
て、前記Ni、Co、Ni―Coのいずれかの金属被膜
層の厚さは100〜10000Åである特許請求の範囲第
１項記載の酸化物陰極。[Claims] 1 Ni and at least one high melting point metal 2
In an oxide cathode formed by depositing an electron-emitting alkaline earth metal oxide on a base metal plate made of an alloy containing at least % by weight, the surface of the base metal plate on which the oxide is deposited is: Ni, Co, Ni-Co on the top surface of the carbon coating layer formed on the base metal plate.
An oxide cathode characterized by being formed by depositing any one of the metal coating layers. 2 The base metal plate is made of Zr, Al, Mg, Si, Ti,
The oxide cathode according to claim 1, which contains at least one reducing element selected from the group of reducing elements such as U, Cr, Nb, and Th. 3. The oxidation method according to claim 1, wherein the carbon coating layer has a thickness of 50 to 1000 Å, and the Ni, Co, or Ni-Co metal coating layer has a thickness of 100 to 10000 Å. object cathode.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP9457178A JPS5521844A (en) | 1978-08-04 | 1978-08-04 | Metal oxide cathode |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP9457178A JPS5521844A (en) | 1978-08-04 | 1978-08-04 | Metal oxide cathode |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5521844A JPS5521844A (en) | 1980-02-16 |
| JPS6216490B2 true JPS6216490B2 (en) | 1987-04-13 |
Family
ID=14113982
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP9457178A Granted JPS5521844A (en) | 1978-08-04 | 1978-08-04 | Metal oxide cathode |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5521844A (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS58154129A (en) * | 1982-03-08 | 1983-09-13 | Mitsubishi Electric Corp | Electron-tube cathode |
-
1978
- 1978-08-04 JP JP9457178A patent/JPS5521844A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5521844A (en) | 1980-02-16 |
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