200845097 九、發明說明： 【發明所屬之技術領域】 本申請案係根據並主張在2007年1月17日所申請之 曰本專利申請案第2007-795 8號之優先權的利益，在此將 其揭露完全納入參考。 本發明係關於一種冷陰極螢光燈，尤其是一種可以改 善用在冷陰極螢光燈之電極。 【先前技術】 冷陰極螢光燈，例如，已被廣泛使用當作液晶顯示器 的背光源。一般的冷陰極螢光燈具有：玻璃管，其具有形 成在內壁表面上之螢光材料層及塡充在其中稀有氣體；一 對位在玻璃管相對端使彼此相面對之電極；及具有一端連 接到電極，而另一端延伸到玻璃管外部之導線。 上述用在冷陰極螢光燈之電極具有一端爲開口，而另 一端爲封口之圓柱形狀。因爲鎳（Ni)的價格低，而且m具 有高的加工性，所以Ni係典型用於電極之材料。在下文 中，將電極的封口端稱爲底部。 第1 a圖到第1 e圖爲數種橫截面形狀不同的電極之範 例。示於第la圖和第lb圖之電極30和31係藉由擠壓加 工（press working)所製造之電極。示於第lc圖、第Id圖和 第1 e圖之電極4 0、4 1和4 2係藉由冷鍛釘頭製造之電極。 幾乎所有目前所使用的電極都是藉由擠壓加工或冷鍛釘頭 製造。 在電極係藉由擠壓加工製造的情形下’具有〇. 1到0.2 200845097 mm厚度之金屬板被形成杯子的形狀，如第la圖或第lb圖 所示（藉由執行深引伸（deep drawing))。在電極係藉由冷鍛 釘頭製造的情形下，敲打金屬線的端面使其凹陷，以形成 杯子的形狀，如第1 c圖、第1 d圖或第1 e圖所示。 如第1 a圖到第1 e圖所示，藉由擠壓加工所製造之電 極30和31和藉由冷鍛釘頭製造之電極40、41和42的橫 截面形狀並沒有很大的不同。尤其，對於電極的底部內表 面50，平坦和筆直都是一般的。 但是，電極和具有電極之冷陰極螢光燈會有p個廣爲 人知的問題：抗濺鍍性和暗可啓動性（dark startability)，下 面將詳細說明。 (關於抗濺鍍性） 如上所述，具有上述電極之冷陰極螢光燈在很多種情 形下被用以當作液晶顯示器的背光源。但是，隨著液晶顯 示器之尺寸，解析度，和照度的增加，施加到電極之電壓 要更高。若應用到電極之電壓變得更高，游離的稀有氣體 被加速，然後以高速對著電極表面，特別是底部內表面撞 擊。換言之，濺鍍現象變得很明顯。尤其，在具有平坦和 筆直的底部表面之電極的情形下，游離稀有氣體之撞擊係 集中在底部內表面上，所以底部在中心會被局部地磨損。 若磨損進行到連接底部的外表面之導線，則電極和導線會 彼此相互斷絕。電極的壽命會因此機制而縮短，而且也不 能得到液晶顯示器背光源所要求的壽命。 200845097 此外，釋放的電極材料藉由與玻璃管中的汞反應而形 成汞齊，然後形成的汞齊沉積在電極的內表面（尤其是內側 表面）上，而妨礙電子從電極的底部內表面輻射到外部。 日本專利公開桌2005-71972號說明一種具有半球形底 部內表面之電極（參見段落[0022]和第1圖）。但是，日本專 利公開第2005-71972號並未包含製造電極半球形底部內表 面的技術方式之說明。日本專利公開第2005 -7 1 972號所揭 露之技術預先假定使用高熔點材料，如鎢（W)或鉬（Mo)，以 解決由鍊當作基本材料所形成之電極技術上的問題。因 此，日本專利公開第2005 -7 1 972號並未揭露或提出有效的 方式，以解決上述有關由鎳當作基本材料所形成之電極的 抗濺鍍性之問題。 (關於暗可啓動性） 液晶顯示器或其類似物的背光源單元一般具有封閉的 結構。即，被提供當作背光源之冷陰極螢光燈一般係放置 在外部光不能進入之暗空間中。另一方面，在一啓動時， 冷陰極螢光燈需要觸發放電之起始電子。一般係使用熱電 子，光電子，藉由高電場發射之電子，在自然世界中之宇 宙射線或其類似物當作起始電子。但是，在與外部隔離之 暗空間中，這幾種電子的每一種之數量係相當不足，而因 此冷陰極螢光燈的可啓動性很低。 有一種習知的技術可以藉由散佈電子發射材料（如釔 (Y))改善暗可啓動性（參見日本專利公開第2 0 0 5 - 7 1 9 7 2號的 200845097 段落[0013])。 但是，在其內散佈有釔之電極係藉由通常被用以當作 電極製造法之擠壓加工而予以製造的情形下，暗可啓動性 並未充分改善。本發明之發明人等認真地硏究此現象，並 發現此現象之原因，說明如下。在其內散佈有釔之電極係 藉由擠壓加工而予以製造的情形下，執行下面槪述之製程。 先製造其內散佈有適量釔之鎳系金屬材料（錠塊）。對 錠塊進行特定次數之輾壓（rolling)及表面拋光，以製造具有 0 · 1到0 · 2 mm厚度之條狀金屬板。將金屬板擠壓成杯子的 形狀，如第1 a圖或第1 b圖所示，最後對形成的物品執行 最後拋光。 但是，釔的加入造成材料的延展性之顯著減少，而使 得材料表面變脆。於是使錠塊的輾壓很難執行。熔化的鎳 向下流在電極表面上，而且也會造成在擠壓和在最後拋光 時，釔從電極表面脫落。熔化的鎳流動的結果係在晶粒邊 界分離之釔被鎳覆蓋，並且大致上會沒有釔曝露在電極表 面。曝露在電極表面之釔量也會因釔的脫落而降低。此意 味著藉由使用將釔加入到鎳中而製備之材料製造電極並不 能有效改善暗可啓動性。 【發明內容】 本發明之目的係要改善由鎳構成之材料和散佈在鎳中 之電子發射材料所製成的電極，其抗濺鍍性和起始電子發 射能力，於是可以改善冷陰極螢光燈的壽命和暗可啓動性。 200845097 根據本發明，本發明提供一種冷陰極螢光燈，其包含： 玻璃管，其至少含有以藉由密閉玻璃之氣密方式密封塡充 在其內部空間之稀有氣體，而且還具有形成在其內壁表面 上之螢光材料層；配置在內部空間中之管狀電極；及導線， 其一端連接到電極的底部外表面，而另一端藉由穿透密閉 玻璃延伸到玻璃管的外部。電極係由鎳系金屬材料形成， 其中有散佈釔和/或氧化釔；底部外表面係平坦的表面；及 相對於底部外表面之底部內表面係彎曲的表面。 在本發明之冷陰極螢光燈中，在電極內表面中之釔和/ 或氧化釔的曝露區域相對於鎳的曝露區域之比例較佳爲 0.2 1 %或更多。 根據本發明，本發明提供一種用在冷陰極螢光燈之電 極的製造方法，該方法包含：製備其內散佈有釔或氧化釔 之鎳系金屬線；及壓印和凹陷金屬線的端表面，使金屬線 形成具有彎曲內表面之底部部分和面對底部部分之開口部 分的管狀。 在本發明之電極製造方法中，散布於金屬線中之釔和/ 或氧化釔的量較佳爲等於或大於0.18 wt%，且等於或小於 0 · 6 8 w t %。 根據參考下面說明本發明範例之附圖的敘述，本發明 上述的和其他的目的、特徵及優點將會變得很明顯。 【實施方式】 下面將參考附圖，詳細說明根據本發明之示範性實施 200845097 例之冷陰極螢光燈範例。第2圖爲根據本示範性 冷陰極螢光燈之結構的示意橫截面圖。 示於第2圖之玻璃管2係由硼矽酸鹽玻璃形 密閉玻璃（珠狀玻璃3)之氣密方式密封玻璃管2之 玻璃管2的外徑範圍爲1.5到6.0 mm，較佳之範 到3.0 mm。玻璃管2的材料也可以爲鉛玻璃，鈉 鉛玻璃，或其類似者。 螢光材料層（未圖示）係被提供在玻璃管2整 f '. 內壁表面4上。根據冷陰極螢光燈1之目的和用 - 螢光材料層之螢光材料可以選自存在的或新的螢 * 如鹵磷酸鹽螢光材料和稀土族螢光材料。再者， 層可以由藉由混合兩種或以上之螢光材料所製備 料而形成。 預定量的稀有氣體，如氬氣、氣氣或氖氣， 的汞被封在由內壁表面4所圍繞之玻璃管2的內 〔 中，而內部空間5壓力被減少到小於大氣壓力。 一對電極單元6分別被提供在玻璃管2之相 一個電極單元6都具有管狀電極7和連接到電極 外表面8之導線9。被提供在一個電極單元6之電 置在玻璃管2的內部空間5之終端的內側位置， 部空間5的終端特定一小段距離，同時面對提供 極單元6之電極7。每一個導線9的一端係被焊接 7的底部外表面8，而另一端則藉由穿透珠狀玻璃 實施例之 成。以由 相對端。 :圍爲1 .5 玻璃，低 個長度的 途，形成 光材料， 螢光材料 的螢光材 和預定量 部空間5 對端。每 7的底部 極7係配 其距離內 在另一電 對應電極 3延伸到 -10- 200845097 玻璃管2的外部。在本示範性實施例中之冷陰極螢光燈1 具有上述之基本結構。 示於第2圖之電極單元6將參考第3圖和第4圖更詳 細的說明。第3圖爲提供在冷陰極螢光燈1中之電極單元 6的放大立體圖。第4a圖和第4b圖爲不同橫截面形狀之電 極7之範例的縱向橫截面圖。 如第3圖所示，建構電極單元6之電極7具有圓柱狀（類 似杯形）之外部顯露，在其一端具有開口 1 0，而在另一端以 底部1 1封閉。如第4a圖和第4b圖所示，電極7的底部內 表面12係具有特定曲率之彎曲表面，而底部外表面8則是 平坦的表面。導線9的一端表面1 3係被焊接到電極7之平 坦的底部外表面8 (第3圖）。 電極7係藉由對具有直徑大約和電極7相同之金屬線 執行冷鍛釘頭而形成，使得金屬線形成杯子的形狀，如第 3圖和第4圖所不。尤其’錬系金屬材料（基本材料淀塊） U 係由鎳（Ni)製造，其中熔解且散佈有釔（Y)或氧化釔 (Y2〇〇。基於其特性，釔或氧化釔係選擇性沉澱在基本材料 錠塊中之結晶邊界區域。 上述之基本材料錠塊被加工成預定線徑之金屬線。尤 其，加工步驟如下：熱乳、伸線、退火、磨削、連續執行 伸線和退火以製造金屬線。接著’將金屬線切割成預定的 長度，使衝壓機敲擊經切割之金屬線的一端表面而使之凹 陷。在此製程中’同時形成底部內表面（彎曲表面）1 2和面 -11- 200845097 對底部內表面12之開口 10，第4a圖 因爲電極7係藉由上述之冷鍛釘 由擠壓加工所形成者，沒有熔化的鎳 且釔不會從表面脫落。因此，散佈在基 之中的釔或氧化釔會充分地曝露在電 所有時間發射自釔或氧化釔之電子係 保即使在暗空間中也可以改善可起動 ^ 氧化釔不僅均勻地存在在電極7的表 內部，所以即使當表面的釔或氧化釔 被磨損時，內部之釔或氧化釔也會連糸 長期保持改善的可啓動性。 當製作基本材料錠塊時，若加入 量超過1.1 wt%，則基本材料錠塊的硬 藉由伸線或冷鍛釘頭來加工的程度。 較佳爲將釔或氧化釔的量設定爲0.68 U 若釔或氧化釔的量過少，則暗可 善。較佳爲在電極內表面之釔或氧化 曝露區域的0.21 %或更高。若釔或氧 充分曝露，則可以有效改善暗可啓動 表面之釔或氧化釔的曝露區域之比例 爲了設定釔或氧化釔的曝露區域 之比例爲0.2 1 %或更高，有必要藉由在 wt%或更高的釔或氧化釔來製造基本木 和第4b圖所示。 頭製造，所以不像藉 會在表面上流動，而 本材料錠塊（金屬線） 極表面上。結果，在 當作起始電子，以確 性。再者，因爲釔或 面，也存在在電極的 因濺鍍或其類似者而 竇出現。因此，可以 鎳中之釔或氧化釔的 化會進行到使其難以 從可加工性的觀點， w t %或更少。 啓動性並不能充分改 釔的曝露區域係鎳之 化釔在電極內表面被 性。因此，在電極外 可以爲0.2 1 %或更少。 相對於鎳的曝露區域 鎳中均勻地散佈0.18 ί料錠塊。 -12- 200845097 如上所述，散佈在鎳中之釔或氧化釔的量較佳爲等於 或大於0.1 8 w t %，並且等於或小於0.6 8 w t %。 因爲電極7之底部內表面12係彎曲表面（球形表面）， 所以游離的高速稀有氣體均勻地對著整個底部內表面12 撞擊。因此，底部內表面1 2的任何部分大致不可能因濺鍍 而被局部磨損。電極材料（鎳）的濺鍍速率也會減少，所以 汞齊的產生量會減少。結果，從電極發射的電子大致不可 能因沉積在電極內表面上之汞齊而受阻礙。 Γ' 一 在上述中，提出三氧化二釔（γ2〇3)作爲氧化釔的範例。 但是’在製造基本材料紅塊之製程中，散佈在電極中之氧 化釔或混合在鎳中之氧化釔並不限定是三氧化二釔。釔具 有很高的活性及容易氧化的特性。因此，其在與鎳混合時， 可以很方便地以氧化釔的形式混合釔。但是，電極可以由 藉由混合金屬釔（Υ)和鎳所製備之金屬材料而形成。此外， 電極也可以由藉由混合氧化釔、釔和鎳所製作之基本材料 U 錠塊製成。因爲釔很容易氧化，所以在藉由混合釔和鎳製 作基本材料錠塊之製程步驟和其他步驟中，釔可能改變成 氧化釔。此外，在此情形下，釔和氧化釔兩者皆散佈在由 基本材料錠塊製作之電極中。簡言之，散佈在電極中之氧 化釔可藉由以氧化釔的形予以混合在鎳中而存在，或藉由 在製作基本材料鏡塊之步驟或不同之步驟中予以氧化而存 在。 具有去氧效果之金屬可以散佈在電極中，以得到進一 -13- 200845097 步改善的暗可啓動性。此是因爲部分已氧化的釔可以藉由 具有去氧效果之金屬而予以還原。已經證實可以藉由具有 去氧效果之金屬改善抗濺鍍性。 具有去氧效果之金屬的範例爲鈦（Ti)，錳（Μη)，锆 (Zr)，和給（Hf)。 若具有去氧效果之金屬爲鈦，則混合物中鈦的比例較 佳爲0.009到0.800 wt%。在具有去氧效果之金屬爲錳之情 形下，則泥合物中錳的比例較佳爲1.1到4.0 wt%。在具有 f 去氧效果之金屬爲鉻或給之情形下，則混合物中锆或給的 比例較佳爲0.05到1.10 wt %。 雖然本發明已使用特定的術語說明較佳實施例，但是 如此的說明只是爲了解釋目的，而且應該要瞭解在不脫離 後述之申請專利範圍的精神或範圍的情況下可進行數種改 變和變化。 【圖式簡單說明】 I, 第la圖到第Id圖爲在相關技術中數種橫截面形狀不 同之電極範例的放大橫截面圖； 第2圖爲本發明示範性實施例中冷陰極螢光燈之範例 的示意橫截面圖； 第3圖爲示於第2圖之電極單元的放大立體圖；及 第4a圖和第4b圖爲示於第1圖之數種不同橫截面形 狀之電極範例的放大橫截面圖。 【主要元件符號說明】 1 冷陰極螢光燈 -14- 200845097 2 玻 璃 管 3 珠 狀 玻 璃 4 內 壁 表 面 5 內 部 空 間 6 電 極 單 元 7,30,31,40,41,42 電 極 8 底 部 外 表 面 9 導 線 10 開 P 11 底 部 12,50 底 部 內 表 靣 13 丄山 m 表 面 -15-。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 Its disclosure is fully incorporated into the reference. The present invention relates to a cold cathode fluorescent lamp, and more particularly to an electrode which can be suitably used in a cold cathode fluorescent lamp. [Prior Art] Cold cathode fluorescent lamps, for example, have been widely used as backlights for liquid crystal displays. A general cold cathode fluorescent lamp has: a glass tube having a layer of a fluorescent material formed on an inner wall surface and a rare gas filled therein; and a pair of electrodes facing each other at opposite ends of the glass tube; A wire having one end connected to the electrode and the other end extending to the outside of the glass tube. The electrode used in the cold cathode fluorescent lamp described above has a cylindrical shape with one end open and the other end sealed. Since nickel (Ni) is low in cost and m has high processability, Ni is typically used as a material for electrodes. Hereinafter, the sealing end of the electrode is referred to as the bottom. Figures 1a through 1e are examples of electrodes with different cross-sectional shapes. The electrodes 30 and 31 shown in Figures la and lb are electrodes fabricated by press working. The electrodes 4 0, 4 1 and 4 2 shown in Figures lc, Id and 1 e are electrodes made by cold forging heads. Almost all of the electrodes currently in use are manufactured by extrusion or cold forging nail heads. In the case where the electrode system is manufactured by extrusion processing, a metal plate having a thickness of 1 to 0.2 200845097 mm is formed into a cup shape as shown in FIG. 1 or FIG. 1b (by performing deep drawing (deep drawing) )). In the case where the electrode is manufactured by a cold forging nail head, the end face of the wire is tapped to be recessed to form the shape of the cup as shown in Fig. 1c, Fig. 1d or Fig. 1e. As shown in Figs. 1a to 1e, the cross-sectional shapes of the electrodes 30 and 31 manufactured by extrusion processing and the electrodes 40, 41 and 42 manufactured by cold forging nails are not greatly different. . In particular, for the inner surface 50 of the bottom of the electrode, flatness and straightness are common. However, electrodes and cold cathode fluorescent lamps with electrodes have p known problems: splash resistance and dark startability, as will be described in more detail below. (Regarding Sputter Resistance) As described above, the cold cathode fluorescent lamp having the above electrode is used as a backlight of a liquid crystal display in many cases. However, as the size, resolution, and illuminance of the liquid crystal display increase, the voltage applied to the electrodes is higher. If the voltage applied to the electrodes becomes higher, the free rare gas is accelerated and then hits the electrode surface at a high speed, particularly the bottom inner surface. In other words, the sputtering phenomenon becomes apparent. In particular, in the case of an electrode having a flat and straight bottom surface, the impact of the free rare gas is concentrated on the inner surface of the bottom, so that the bottom is locally worn at the center. If the wear progresses to the wire connecting the outer surface of the bottom, the electrode and the wire are cut off from each other. The life of the electrode is shortened by this mechanism and the lifetime required for the backlight of the liquid crystal display cannot be obtained. 200845097 In addition, the released electrode material forms an amalgam by reacting with mercury in the glass tube, and then the formed amalgam is deposited on the inner surface (especially the inner side surface) of the electrode, preventing electrons from being radiated from the bottom inner surface of the electrode. To the outside. Japanese Patent Laid-Open Publication No. 2005-71972 describes an electrode having a hemispherical bottom inner surface (see paragraphs [0022] and 1). However, Japanese Patent Laid-Open Publication No. 2005-71972 does not contain a description of the technical means for producing the inner surface of the hemispherical bottom of the electrode. The technique disclosed in Japanese Patent Laid-Open Publication No. 2005-7 972 presupposes the use of a high melting point material such as tungsten (W) or molybdenum (Mo) to solve the technical problem of the electrode formed by the chain as a base material. Therefore, Japanese Patent Laid-Open No. 2005-7 972 does not disclose or suggest an effective manner to solve the above-mentioned problem of the sputter resistance of an electrode formed of nickel as a base material. (About dark startability) A backlight unit of a liquid crystal display or the like generally has a closed structure. That is, a cold cathode fluorescent lamp that is provided as a backlight is generally placed in a dark space into which external light cannot enter. On the other hand, at the start-up, the cold cathode fluorescent lamp needs to trigger the starting electrons of the discharge. In general, thermoelectrons, photoelectrons, electrons emitted by a high electric field, and neutron rays or the like in the natural world are used as starting electrons. However, in the dark space isolated from the outside, the number of each of these kinds of electrons is quite insufficient, and thus the cold cathode fluorescent lamp has low startability. There is a known technique for improving the dark startability by dispersing an electron-emitting material such as ytterbium (Y) (see Japanese Patent Laid-Open Publication No. 2008-200597, paragraph [0013]). However, in the case where the electrode in which the ruthenium is dispersed is manufactured by extrusion processing which is generally used as an electrode manufacturing method, the dark startability is not sufficiently improved. The inventors of the present invention have earnestly studied this phenomenon and found out the cause of this phenomenon as explained below. In the case where the electrode in which the crucible is dispersed is manufactured by extrusion processing, the process described below is performed. First, a nickel-based metal material (ingot) in which an appropriate amount of niobium is dispersed is produced. The ingot is subjected to a certain number of rolling and surface polishing to produce a strip of metal having a thickness of 0·1 to 0. 2 mm. The metal plate is extruded into the shape of the cup, as shown in Fig. 1a or Fig. 1b, and finally the final polishing is performed on the formed article. However, the addition of niobium results in a significant reduction in the ductility of the material, which makes the surface of the material brittle. Therefore, the rolling of the ingot is difficult to perform. The molten nickel flows down the surface of the electrode and also causes the crucible to fall off the surface of the electrode during extrusion and at the final polishing. The result of the flow of molten nickel is covered by nickel at the edge of the grain boundary separation, and substantially no flaws are exposed on the surface of the electrode. The amount of enthalpy exposed to the surface of the electrode is also reduced by the detachment of the enamel. This means that the manufacture of the electrode by using a material prepared by adding cerium to nickel does not effectively improve the dark startability. SUMMARY OF THE INVENTION The object of the present invention is to improve an electrode made of nickel and an electron-emitting material dispersed in nickel, which has anti-sputtering property and initial electron emission capability, thereby improving cold cathode fluorescent light. Lamp life and dark startability. According to the present invention, there is provided a cold cathode fluorescent lamp comprising: a glass tube containing at least a rare gas sealed in a hermetic manner by a hermetic glass, and having a gas formed therein a layer of phosphor material on the inner wall surface; a tubular electrode disposed in the inner space; and a wire having one end connected to the outer surface of the bottom of the electrode and the other end extending through the sealed glass to the outside of the glass tube. The electrode system is formed of a nickel-based metal material having dispersed ruthenium and/or ruthenium oxide; a flat outer surface of the bottom surface; and a curved inner surface with respect to the bottom outer surface of the bottom outer surface. In the cold cathode fluorescent lamp of the present invention, the ratio of the exposed area of ruthenium and/or ruthenium oxide in the inner surface of the electrode to the exposed area of nickel is preferably 0.21% or more. According to the present invention, there is provided a method of fabricating an electrode for use in a cold cathode fluorescent lamp, the method comprising: preparing a nickel-based metal wire having yttrium or yttrium oxide dispersed therein; and embossing and recessing the end surface of the metal wire The metal wire is formed into a tubular shape having a bottom portion of the curved inner surface and an opening portion facing the bottom portion. In the electrode manufacturing method of the present invention, the amount of ruthenium and/or ruthenium oxide dispersed in the metal wire is preferably equal to or more than 0.18 wt%, and equal to or less than 0 · 6 8 w t %. The above and other objects, features and advantages of the present invention will become apparent from [Embodiment] An example of a cold cathode fluorescent lamp according to an exemplary embodiment of the present invention, 200845097, will be described in detail below with reference to the accompanying drawings. Fig. 2 is a schematic cross-sectional view showing the structure of a cold cathode fluorescent lamp according to the present invention. The glass tube 2 shown in Fig. 2 is a glass tube 2 which is sealed by a borosilicate glass-shaped sealed glass (bead glass 3) in an airtight manner, and has an outer diameter ranging from 1.5 to 6.0 mm, preferably a vane. To 3.0 mm. The material of the glass tube 2 may also be lead glass, sodium lead glass, or the like. A layer of phosphor material (not shown) is provided on the inner wall surface 4 of the glass tube 2. Depending on the purpose of the cold cathode fluorescent lamp 1 and the fluorescent material of the phosphor material layer, it may be selected from existing or new fluorescent materials such as a halogen phosphate fluorescent material and a rare earth fluorescent material. Further, the layer may be formed by mixing two or more kinds of phosphor materials. A predetermined amount of a rare gas such as argon gas, gas gas or helium gas is sealed in the inside of the glass tube 2 surrounded by the inner wall surface 4, and the internal space 5 pressure is reduced to less than atmospheric pressure. A pair of electrode units 6 are respectively provided in the phase of the glass tube 2. One of the electrode units 6 has a tubular electrode 7 and a wire 9 connected to the electrode outer surface 8. The electrode unit 6 is provided at the inner side of the terminal of the inner space 5 of the glass tube 2, and the terminal of the space 5 is specified for a small distance while facing the electrode 7 of the supply unit 6. One end of each of the wires 9 is welded to the bottom outer surface 8 of the bottom, and the other end is formed by penetrating the beaded glass embodiment. By the opposite end. : The circumference is 1.5 glass, and the lower length forms the light material, and the fluorescent material of the fluorescent material and the predetermined amount of space are 5 opposite. The bottom pole 7 of each 7 is spaced within the distance from the other electrical counterpart electrode 3 to the outside of the -10- 200845097 glass tube 2. The cold cathode fluorescent lamp 1 in the present exemplary embodiment has the above-described basic structure. The electrode unit 6 shown in Fig. 2 will be explained in more detail with reference to Figs. 3 and 4. Fig. 3 is an enlarged perspective view showing the electrode unit 6 provided in the cold cathode fluorescent lamp 1. Figures 4a and 4b are longitudinal cross-sectional views of examples of electrodes 7 of different cross-sectional shapes. As shown in Fig. 3, the electrode 7 of the electrode unit 6 is constructed to have an outer appearance of a cylindrical shape (like a cup shape) having an opening 10 at one end and a bottom 1 1 at the other end. As shown in Figures 4a and 4b, the bottom inner surface 12 of the electrode 7 is a curved surface having a specific curvature, and the bottom outer surface 8 is a flat surface. One end surface 13 of the wire 9 is welded to the flat bottom outer surface 8 of the electrode 7 (Fig. 3). The electrode 7 is formed by performing a cold forging nail head having a metal wire having a diameter approximately the same as that of the electrode 7, so that the metal wire forms the shape of the cup, as shown in Figs. 3 and 4. In particular, the lanthanide metal material (basic material deposit) U is made of nickel (Ni), in which yttrium (Y) or yttrium oxide (Y2 yttrium is dispersed and dispersed. Based on its characteristics, cerium or lanthanum oxide is selectively precipitated. The crystallization boundary region in the ingot of the basic material. The above-mentioned basic material ingot is processed into a metal wire of a predetermined wire diameter. In particular, the processing steps are as follows: hot milk, wire drawing, annealing, grinding, continuous execution of the wire and annealing To manufacture a metal wire. Then 'cut the metal wire to a predetermined length, causing the punch to tap the end surface of the cut metal wire to dent. In this process, 'the bottom inner surface (curved surface) is simultaneously formed 1 2 No.-11- 200845097 The opening 10 of the bottom inner surface 12, Fig. 4a, because the electrode 7 is formed by extrusion processing by the above-mentioned cold forging nail, there is no molten nickel and the crucible does not fall off from the surface. The ruthenium or ruthenium oxide dispersed in the base will be fully exposed to electrons emitted from the ruthenium or ruthenium oxide at all times. Even in dark spaces, it can be improved. The ruthenium oxide is not only uniformly present in electricity. The inside of the table of 7, so even when the surface of the crucible or cerium oxide is worn, the internal crucible or cerium oxide will maintain improved startability for a long time. When making the basic material ingot, if the amount is more than 1.1 wt %, the degree of hard processing of the ingot of the basic material by the wire or cold forging head. It is preferable to set the amount of niobium or tantalum oxide to 0.68 U. If the amount of niobium or tantalum oxide is too small, the darkness is good. Preferably, it is 0.21% or more of the ruthenium or oxidized exposed area on the inner surface of the electrode. If the ruthenium or oxygen is sufficiently exposed, the ratio of the exposed area of the ruthenium or ruthenium oxide on the dark startable surface can be effectively improved in order to set the ruthenium or oxidation. The ratio of the exposed area of the crucible is 0.2 1% or higher, it is necessary to manufacture the basic wood by the crucible or yttrium oxide at wt% or higher and the figure shown in Fig. 4b. The head is manufactured, so it is not like borrowing on the surface. The upper part flows on the surface of the ingot (metal wire). As a result, it is regarded as the starting electron to be confirmed. Furthermore, because of the 钇 or the surface, there is also the sinus in the electrode due to sputtering or the like. Appear. Therefore, it can be in nickel Or the oxidation of ruthenium oxide may proceed to make it difficult to be from the viewpoint of workability, wt% or less. The start-up property is not sufficiently improved, and the exposed region is nickel bismuth on the inner surface of the electrode. Therefore, at the electrode The outer portion may be 0.2 1 % or less. The 0.18 inch ingot is uniformly dispersed in the nickel relative to the exposed area of nickel. -12- 200845097 As described above, the amount of niobium or tantalum oxide dispersed in nickel is preferably equal to or equal to Or more than 0.1 8 wt%, and equal to or less than 0.6 8 wt%. Since the bottom inner surface 12 of the electrode 7 is a curved surface (spherical surface), the free high-speed rare gas uniformly hits the entire bottom inner surface 12. Any portion of the bottom inner surface 12 is substantially unlikely to be partially worn by sputtering. The sputtering rate of the electrode material (nickel) is also reduced, so the amount of amalgam produced is reduced. As a result, electrons emitted from the electrodes are substantially prevented from being hindered by the amalgam deposited on the inner surface of the electrodes. Γ' In the above, an antimony trioxide (γ2〇3) was proposed as an example of cerium oxide. However, in the process of manufacturing a red block of a base material, the cerium oxide dispersed in the electrode or the cerium oxide mixed in the nickel is not limited to ruthenium trioxide. The cookware has high activity and easy oxidation properties. Therefore, it is convenient to mix ruthenium in the form of ruthenium oxide when it is mixed with nickel. However, the electrode may be formed of a metal material prepared by mixing metal ruthenium (iridium) and nickel. Further, the electrode may also be made of a base material U ingot made by mixing cerium oxide, lanthanum and nickel. Since ruthenium is easily oxidized, ruthenium may be changed to ruthenium oxide in a process step and other steps of making a base material ingot by mixing ruthenium and nickel. Further, in this case, both tantalum and niobium oxide are dispersed in the electrode made of the ingot of the basic material. In short, the cerium oxide dispersed in the electrode may be present by mixing in the form of yttrium oxide in the nickel, or by oxidizing in the step of fabricating the base material block or in a different step. A metal having an oxygen scavenging effect can be dispersed in the electrode to obtain a dark startability improved by the step -13 - 200845097. This is because a part of the oxidized ruthenium can be reduced by a metal having a deoxidizing effect. It has been confirmed that the sputtering resistance can be improved by the metal having an deoxidizing effect. Examples of metals having an oxygen scavenging effect are titanium (Ti), manganese (Mn), zirconium (Zr), and (Hf). If the metal having an oxygen scavenging effect is titanium, the proportion of titanium in the mixture is preferably from 0.009 to 0.800 wt%. In the case where the metal having an oxygen scavenging effect is manganese, the proportion of manganese in the mud is preferably from 1.1 to 4.0% by weight. In the case where the metal having the deoxygenation effect is chromium or is given, the ratio of zirconium or feed in the mixture is preferably from 0.05 to 1.10 wt%. While the invention has been described with respect to the preferred embodiments of the embodiments of the embodiments of the present invention, it is understood that the invention may be modified and varied without departing from the spirit and scope of the appended claims. BRIEF DESCRIPTION OF THE DRAWINGS I, the first to the first Id are enlarged cross-sectional views of an example of electrodes having different cross-sectional shapes in the related art; FIG. 2 is a cold cathode fluorescent light in an exemplary embodiment of the present invention. A schematic cross-sectional view of an example of a lamp; FIG. 3 is an enlarged perspective view of the electrode unit shown in FIG. 2; and FIGS. 4a and 4b are examples of electrodes of different cross-sectional shapes shown in FIG. Zoom in on the cross section. [Main component symbol description] 1 Cold cathode fluorescent lamp-14- 200845097 2 Glass tube 3 Beaded glass 4 Inner wall surface 5 Internal space 6 Electrode unit 7, 30, 31, 40, 41, 42 Electrode 8 Bottom outer surface 9 Wire 10 open P 11 bottom 12, 50 bottom inner surface 丄 13 丄 mountain m surface -15-