.1314335 、 九、發明說明： 【發明所屬之技術領域】 本發明涉及一種用於照明用光源、個人電腦（personal c 〇 m p u t e r)之監視器、液晶電視、汽車導航系統（c a r navigation system)用之液晶顯示器（iiquid crystai display) 等的背光（backlight)等之冷陰極螢光燈用電極材料之製 法’尤以於金屬基材形成有發射體（e m i 11 e r)層之狀態下將電 極拉延成形時，可防止發射體層剝離之技術。 # 【先前技術】 向來冷陰極螢光燈有各種用途，最近於液晶顯示器之 背光的採用多受探討。裝備液晶顯示器之機器主要係以電 池驅動，用於液晶顯示器之背光之冷陰極螢光燈，有低耗 電之高度要求。爲實現低耗電，要點在降低無助於發光之 電極之壓降。近年來開始有TV用液晶元件之採用，壽命比 以往長且亮度高之冷陰極螢光燈受到期待。 冷陰極螢光燈之構造如第1圖，係於玻璃管1內兩端 ® 配置有藉端子2連接外部之電極3,此玻璃管1內面塗有螢 光體4，並封入惰性氣體及微量汞構成之封入氣體5。於該 兩端之電極3施加高電壓，在低壓汞蒸氣中起輝光放電 (glow discharge)，因該放電激發之汞產生紫外線，同時此 紫外線激發玻璃管1內面之螢光體4使之發光。於此所用 之電極3，近年來係用形成爲杯狀者。將電極形成爲杯狀， 因其形狀所致之空心陰極（hollow cathode)效應，電子易於 自電極內側放射，可降低陰極壓降，有效壓低耗電。爲減 1314335 - 少冷陰極螢光燈之電極損失而高效率化、低耗電化，適用 的電極3之材料，乃含功函數低於其它金屬之第1〜第3族 元素之發射體材料。 如上之發射體材料經塗敷或離子佈値（丨〇1^1&1丨1^)被胃 於杯狀（cup-shaped)金屬基材形成發射體層之杯狀陰極電 極已爲所知，採用如此之杯狀電極之冷陰極螢光燈，電平亟 壓降可較習知棒狀金屬電極低40V左右，得以隨之低耗電 化已見報告（例如，日本專利特開平1 0- 1 4425號公報、特開 • 2000- 1 1 866 號公報）。 並有發射體材料使用Mo、Ta、Nb等高熔點金屬材料， 以抑制燈點亮時之激鍍（sputtering)，減少燈內眾之消耗， 延長壽命之報告（參考例如，日本照明學會誌Vol. 1.87, No. 1 2003 1 5頁，「液晶顯示器冷陰極螢光燈之技術動向」）。 此時’ Μ 〇及T a電極比習知N i電極減少約4 0 %之耗汞量， 有其相當之壽命延長可期。 然而’加工爲杯狀之電極金屬基材內面，不易形成厚 度均勻’牢固附著之發射體層。例如，以塗敷形成發射體 層於杯狀金屬電極時，發射體層厚度不均。金屬電極與發 射體層之附著強度低’螢光燈生產過程中、點亮時有因離 子衝擊發射體層易於脫落之缺點。以浸沾（d i p p 1 n g)形成發 射體層時，有電極外周面亦有發射體層的塗敷之缺失。 以離子佈植形成發射體層時，雖可得附著強度高之發 射體層’卻有發射體材料附著於金屬基材以外之鍍敷裝置 內面’材料良率差之缺點。藉由塗敷或許合適，但因係於 J314335 w 個別杯狀電極基材形成發射體層，有生產 提高之問題。 【發明內容】 本發明係鑑於上述之情事而作，其目 狀電極基材內面形成厚度均勻且牢固附著 生產效率佳生產成本可予降低之冷陰極螢 之製法。 本發明人等爲提升冷陰極螢光燈用電 Φ 率作了探討，於金屬材料之板材形成放 後’以該素材製造杯狀冷陰極螢光燈用電 放電層後進行深拉延等激烈塑性加工則放 搓擦而剝離，故目前實況係尙無該技術之 明人探討了放電層之緻密化並使之牢固附 方法。結果得知，將放電層塗於金屬基材 放電層即牢固附著於金屬基材，作深拉延 本發明係基於以上見解而作，乃備有 ® 於此金屬基材上之放電層，加工成冷陰極 極之冷陰極螢光燈用電極材料之製法，其 射體粉末分散於分散媒體中之粉末塗料塗 成放電層之塗敷步驟，將放電層往金屬基 壓縮步驟，第1壓縮步驟之後自放電層去 外成分之去除步驟，以及，將發射體粉末 之放電層往金屬基材側壓縮之第2壓縮步 將粉末塗料塗於金屬基材上形成之放 效率差製造成本 的在提供可於杯 之發射體層，而 光燈用電極材料 極材料之生產效 電層（發射體層） 極。然而，形成 電層無不受強力 提供。因此本發 著於金屬材料之 後經壓縮加工， 亦不剝離。 金屬基材及形成 螢光燈之放電電 特徵爲包括將發 於金屬基材上形 材側壓縮之第1 除發射體粉末以 以外成分經去除 驟。 電層內部有多數 1314335 λ w 氣孔存在。該氣孔包含溶劑經乾燥蒸發後生成之空隙、混 合粉末塗料之際捲入之空氣粒子等。依本發明由塗敷步驟 形成之放電層，經第1壓縮步驟之壓縮，放電層內部之氣 孔被壓壞而緻密化，同時放電層牢固附著於金屬基材。其 次，於去除步驟，分散媒體等發射體粉末以外之成分遭去 除而生成氣孔，氣孔於第2壓縮步驟經壓壞，放電層再度 緻密化。 並因第2壓縮步驟，放電層厚度得以均勻化，同時放電 # 層更牢固附著於金屬基材。如此之冷陰極螢光燈用電極材料 經例如施以深拉延等之塑性加工即可製造杯狀之冷陰極螢 光燈用電極。此時，放電層已緻密化同時牢固附著於金屬基 材，故可防止塑性加工時，發射體粉末之脫落或剝離。 因此，例如將金屬基材由卷（r ο 11)連續捲出一邊進行本 發明之步驟，其次供給於壓製裝置深拉延成形爲電極等， 可於工廠以連續生產線作處理。因此，依本發明不但可形 成厚度均勻且牢固附著之放電層，冷陰極螢光燈用電極之 ^ 生產效率得以提高而生產成本降低。 因壓縮步驟而放電層牢固附著於金屬基材之理由不確 定。經本發明人等之探討，確認有部分發射體粉末咬入金 屬基材表面，其可推測係理由之一。亦應係發射體粉末相 互間或發射體粉末與金屬基材夾有分散媒體之殘渣而密 著’因大氣壓力而不分離。唯這些只是猜測，本發明當不 限於該等作用之有無。 以由本發明製造之材料形成電極，使用該電極試作冷 1314335 陰極螢光燈時’玻璃管內部一槪無排氣（out gas)之問題發 生。因此’即使有如上之殘渣存在，亦已確認其無害。 【實施方式】 第2圖係本發明之各步驟及放電層狀態之切面圖，圖 中符號1 0係金屬基材，符號1 1係放電層。如第2圖，塗 敷步驟中係於金屬基材10之一面塗上發射體粉末與分散 媒體（有時包含溶劑）混合成漿體狀（slurry)之粉末塗料，經 乾燥或冷卻步驟使粉末塗料固化。以此，溶劑蒸發後形成 # 氣孔。此氣孔經經第1壓縮步驟壓壞，使放電層緻密化。 其次經去除步驟分散媒體蒸發之後形成氣孔。此氣孔經第 2壓縮步驟壓壞，使放電層緻密化。以下詳細說明本發明 之各步驟。 金屬基材可用鎳（Ni)或鎳合金（例如（permaloy))、鐵合 金（例如不銹鋼（s t a i η 1 e s s s t e e 1))，鉻（C r)、鉬（Μ 〇)、钽（T a)、 鈮（Nb)純金屬或2種以上的這些金屬之合金。 發射體粉末宜含功函數低之元素，可用例如鎢酸鋇 _ (Ba2CaW06、BaW04)，六硼化鈣（CaB6)、六硼化鋸（SrB6)、 六硼化鋇（BaB6)、六硼化鑭（LaB6)、六硼化鈽（CeB6)、六硼 化鐯（PrB6)、六硼化鈸（NdB6)、六硼化釤（SmB6)、六硼化銪 (EuB6)、碳化鈦（TiC)、碳化釩（VC)、碳化鉻（ZrC)、碳化鈮 (NbC)、碳化鉬（MoC)、碳化鈴（HfC)、碳化钽（TaC)及碳化 鎢（WC)中之1種或2種以上。 將如上之發射體粉末與分散媒體混合成漿體狀之粉末 塗料塗於金屬基材。分散媒體可用將聚二氟亞乙烯 1314335 (Polyvinylidene fluoride)、丙燦醯樹脂（acrylic resin)、酣 樹脂（phenol resin)、三聚氰胺樹脂（melamine resin)、聚乙 稀樹脂（polyethylene resin)、聚醯亞胺樹脂（polyimide resin)等可溶性樹脂，經丙纖維素（hydroxypropylcellulose)、 甲纖維素（methylcellulose)、明膠（gelatin)等天然或合成多 酿類，伸乙雙硬脂醯胺（ethylenebis stearamide)等高級脂肪 酸中之1種或2種以上溶解於溶劑中者。此時，溶解分散 媒體之溶劑可用如正甲基耻略院酮1 (n-methylpyrrolidone) ^ 之有機溶劑、水。粉末塗料係以將含溶劑之分散媒體與粉 末依質量比約1: 1混合調製爲佳。塗敷步驟後宜進行乾燥 步驟使溶劑蒸發。 分散媒體亦可用經加熱成熔融狀態之熱塑性樹脂、天 然或合成多醣類、硬脂酸鲜（zinc stearate)等金屬皂、高級 脂肪酸中之1種或2種以上。此時，因將分散媒體冷卻至 室溫即固化而可節約能源（energy saving)。塗敷步驟後宜進 行冷卻步驟使分散媒體固化。 m w 塗敷步驟可用浸漬法、噴霧法、印刷法、刷塗法、流 塗（flow coating)法、刮刀法（doctor blade method)之任一。 刮刀法係將粉末塗料附著於金屬基材，以刮刀刮落至一定 厚度之塗敷法，因粉末塗料之厚度可嚴密管控而較合適。 將粉末塗料塗於金屬基材後，乾燥或冷卻以固化，於 金屬基材之一面形成放電層。其次，進行將放電層往金屬 基材側壓縮之第1壓縮步驟。第1壓縮步驟係將金屬基材 及放電層以輥一對夾入爲之。以此’放電層被壓縮而緻密 -10- .1314335 • 化，放電層之厚度均勻化。以溶劑溶解分散媒體時，溶劑 乾燥蒸發後形成氣孔，氣孔於第1壓縮步驟被壓壞。爲達 本發明之目的第1壓縮步驟之壓縮率宜在20 %以上。於此’ 壓縮率係以壓縮前後試樣之板厚爲hG、hi時由（ho-hj/ho χ 1 00表示。 其次，進行自放電層去除發射體粉末以外成分之去除 步驟。去除步驟中進行加熱以使分散媒體蒸發。加熱溫度 及時間係依分散媒體之種類、含量適當選擇。因加熱溫度 φ 達數百°c，爲防發射體粉末氧化，去除步驟宜在氮氣等惰 性氛圍中進行。 其次，進行再度將放電層往金屬基材側壓縮之第2壓 縮步驟。第2壓縮步驟係將金屬基材及放電層以輥一對夾 入爲之。經去除步驟分散媒體蒸發後有氣孔形成，而壓縮 則壓壞氣孔，放電層緻密化。並因第2壓縮步驟，放電層 厚度更加均勻。爲達本發明之目的第2壓縮步驟之壓縮率 宜在50%以上。 Φ 第2壓縮步驟後放電層厚度宜在0.005〜0.05mm。爲 確保放電特性，放電層厚度須在〇 . 〇 〇 5 m m以上。然而，放 電層厚度超過0.05mm則深拉延成形時易於發生剝離。 如上製造之冷陰極螢光燈用電極材料係於金屬基材之 一面形成有發射體粉末構成之放電層者。此放電層因已緻 密化並牢固附著於金屬基材，深拉延形成杯狀電極之際可 防放電層剝離。經第1、第2壓縮步驟放電層厚度均勻， 將電極用於冷陰極螢光燈時放電特性良好。 .1314335 • 實施例 1 .電極之製作 將/\砸化鋼（LaB6)之粉末塗料以〇.〇2mrn之厚度塗於 厚0.30mm的鎳板之一面。粉末塗料係用六硼化鑭47.6質 量％、羥丙纖維素2.4質量％、正甲基吡咯烷酮50.0質量。/。 之混合物。此試樣於空氣中以12〇°C加熱15分鐘使正甲基 吡咯烷酮蒸發，粉末塗料固化。 其次，用壓延輥以壓縮率25 °/。或53 %壓延上述試樣 # (第1壓縮步驟）。其次，在氮氣中於5 00 °C將試樣加熱1小 時，使羥丙纖維素蒸發。其次’用壓延輥以壓縮率5 3 %壓 延上述試樣（第2壓縮步驟）’製作本發明之實施例試樣1 ^ 爲作比較，不進行第1壓縮步驟或第2壓縮步驟以外 如同上述條件製作冷陰極螢光燈用電極材料（試樣2、試樣 3)。不進行第1壓縮步驟而進行第2壓縮步驟之試樣2,於 進行第2壓縮步驟時放電層自金屬基材剝離。 2 ·膠帶剝離試驗 ® 將如上製作之冷陰極螢光燈用電極材料切成適當大小 製作試片，於其放電層貼附玻璃紙膠帶（cellophane tape) 後剝離進行膠帶剝離試驗。結果如表1。表1中放電層之 一部分附著於玻璃紙膠帶而剝離者評估爲「△」，無放電 層之剝離者評估爲「〇」。 1314335 表1 壓縮率(％) 膠帶剝離試輪 180°屈曲試驗 激振試驗 第1壓縮 第2壓縮 試樣1 25 53 〇 〇 〇 _試樣2 53 試樣3 53 _ △ 〇 〇 如表1，進行第1、第2壓縮步驟之試樣丨無放電層之 剝離，而不進行第2壓縮步驟之試樣3有部分放電層剝離。 ^ 不進行第1壓縮步驟之試樣2’因於第2壓縮步驟放電層 剝離，無法進行膠帶剝離試驗。 180°屈曲試驗 以放電層爲內側將試片折曲1 80。進行屈曲試驗，觀察 放電層之剝離情況，結果倂列於表1。如表1，進行第1、 第2壓縮步驟之試樣1及不進行第2壓縮步驟之試樣3皆 無放電層之剝離，評估爲「〇」。 4.激振試驗 ^ 將試片放入注有甲醇（methanol)之超音波洗淨機作超 音波洗淨5分鐘。觀察超音波洗淨後試片放電層之剝離情 況，結果倂列於表1。如表1，進行第1、第2壓縮步驟之 試樣1及不進行第2壓縮步驟之試樣3皆無放電層之剝 離，評估爲「〇」。 如上，不進行第1壓縮步驟之試樣2，因有去除之溶 劑及分散媒體消失後形成之氣孔，放電層呈多孔質狀態， 不耐第2壓縮步驟之變形，放電層崩壞、剝離。不進行第 1314335 '2壓縮步驟之試樣3因分散媒體消失後形成之氣孔，發射 體粉末相互間之結合力低，膠帶剝離耐抗性差。因此確認， 爲使放電層緻密’提升其於金屬基材之附著強度，必須進 行第1、第2壓縮步驟。 5 ·放電層之內部構造 第3圖係試樣1之切面SEM照片。由此照片知，發射 體粉末相互密著’放電層緻密化至幾可確認無氣孔存在。 並可確認有一部分發射體粉末咬入金屬基材表面。 _ 6 ·放電特性 將試樣1深拉延形成第1圖中符號3之杯狀電極，用 此電極製作第1圖之冷陰極螢光燈。本發明之其它實施例 係取代羥丙纖維素及正甲基吡咯烷酮，將硬脂酸鋅以相同 質量％混合以外，依如同試樣1之條件形成電極，製作冷陰 極營光燈。爲作比較，形成僅由鎳板構成之電極，製作冷 陰極螢光燈。以電流供給於以上冷陰極螢光燈，探討電流 與電壓之關係。結果如第4圖所示。 ^ 由第4圖知，使用經本發明之製法製作的電極之冷陰 極螢光燈’與使用僅由鎳板構成之電極的冷陰極螢光燈比 較，放電電壓低，放電特性良好。因此知，本發明已發揮 使用低功函數之發射體粉末的效果。其表示由本發明製作 之冷陰極螢光燈用電極材料，放電層不因拉長延伸加工而 剝離。 【圖式簡單說明】 第1圖 冷陰極線燈之構造切面圖。 -14- 1314335 第2圖 本發明之實施形態的步驟順序圖。 第3圖 冷陰極線燈用電極材料之切面的S EM照片。 第4圖 本發明之實施例中冷陰極線燈之電流與電壓 之關係圖。 【主要元件符號說明】 10 金屬基材 11 放電層BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light source for illumination, a monitor for a personal computer (personal c 〇mputer), a liquid crystal television, and a car navigation system. A method for producing an electrode material for a cold cathode fluorescent lamp such as a backlight such as a liquid crystal display (such as a backlight), in which a metal substrate is formed with an emitter (emi 11 er) layer, and the electrode is drawn and formed. When it is possible to prevent the emitter layer from peeling off. # [Prior Art] There have been various uses for cold cathode fluorescent lamps, and the recent adoption of backlights for liquid crystal displays has been discussed. Machines equipped with liquid crystal displays are mainly battery-driven, cold cathode fluorescent lamps for backlighting of liquid crystal displays, which have high requirements for low power consumption. In order to achieve low power consumption, it is important to reduce the voltage drop of the electrode that does not contribute to light emission. In recent years, there has been a demand for a liquid crystal element for TV, and a cold cathode fluorescent lamp having a longer life than a conventional one and having a high luminance has been expected. The structure of the cold cathode fluorescent lamp is as shown in Fig. 1, which is disposed at the inner ends of the glass tube 1 and is provided with an electrode 3 connected to the outside via the terminal 2. The inner surface of the glass tube 1 is coated with a phosphor 4 and sealed with an inert gas and A small amount of mercury constitutes a sealed gas 5. A high voltage is applied to the electrodes 3 at the both ends, and a glow discharge is performed in the low-pressure mercury vapor, and the ultraviolet rays excited by the discharge generate ultraviolet rays, and the ultraviolet rays excite the phosphors 4 on the inner surface of the glass tube 1 to emit light. . The electrode 3 used herein has been formed into a cup shape in recent years. The electrode is formed into a cup shape, and the hollow cathode effect due to its shape makes it easy for electrons to be radiated from the inside of the electrode, which can reduce the cathode voltage drop and effectively reduce the power consumption. In order to reduce the electrode loss of the 1314335-less cold cathode fluorescent lamp, the material of the electrode 3 is an emitter material having a work function lower than that of the first to third elements of other metals. . It has been known that the above-described emitter material is coated or ion cloth (丨〇1^1&1丨1^) is formed by a cup-shaped metal substrate to form an emitter layer of a cup-shaped cathode electrode. The cold cathode fluorescent lamp using such a cup electrode has a level 亟 pressure drop which is about 40 V lower than that of a conventional rod-shaped metal electrode, and has been reported with low power consumption (for example, Japanese Patent Laid-Open No. 10- Bulletin No. 1 4425, JP-A-2000-01 1 866). The emitter material is made of a high-melting-point metal material such as Mo, Ta, Nb, etc., to suppress the sputtering of the lamp when it is lit, to reduce the consumption of the lamp, and to prolong the life (see, for example, the Japan Illumination Society Vol. 1.87, No. 1 2003 1 5, "Technical Trends of Liquid Crystal Display Cold Cathode Fluorescent Lamps"). At this time, the Μ 〇 and T a electrodes are reduced by about 40% of the mercury consumption than the conventional N i electrode, and their life expectancy is extended. However, it is difficult to form an inner surface of the electrode metal substrate which is processed into a cup shape, and it is difficult to form an emitter layer which is uniformly adhered to a firm thickness. For example, when the emitter layer is formed by coating on the cup-shaped metal electrode, the thickness of the emitter layer is not uniform. The adhesion strength between the metal electrode and the emitter layer is low. In the production process of the fluorescent lamp, there is a disadvantage that the emitter layer is easily detached due to the ion impact. When the emitter layer is formed by dipping (d i p p 1 n g), there is also a lack of coating of the emitter layer on the outer peripheral surface of the electrode. When the emitter layer is formed by ion implantation, it is possible to obtain an emitter layer having a high adhesion strength, but there is a disadvantage that the emitter material adheres to the inner surface of the plating apparatus other than the metal substrate. It may be appropriate to apply by coating, but due to the J314335 w individual cup electrode substrate forming an emitter layer, there is a problem of improved production. SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and a method for producing a cold cathode firefly having a uniform thickness and a strong adhesion and a low production cost can be formed on the inner surface of the target electrode substrate. The inventors of the present invention have discussed the electric Φ rate of a cold cathode fluorescent lamp, and after forming a sheet of a metal material, the electric discharge layer for a cup-shaped cold cathode fluorescent lamp is produced by the material, and then deep drawing is performed. The plastic processing is rubbed and peeled off, so the current situation is that the person who does not have the technology has discussed the densification of the discharge layer and firmly attached it. As a result, it has been found that the discharge layer is applied to the discharge layer of the metal substrate, that is, firmly adhered to the metal substrate, and is deep drawn. The present invention is based on the above findings, and is provided with a discharge layer on the metal substrate. A method for preparing an electrode material for a cold cathode fluorescent lamp which is a cold cathode, a coating step of coating a powder coating on a discharge layer in a dispersion medium, and a step of compressing the discharge layer to a metal base, a first compression step After the step of removing the external component from the discharge layer and the second compression step of compressing the discharge layer of the emitter powder toward the metal substrate side, the powder coating is applied to the metal substrate to form a manufacturing efficiency difference. It can be used in the emitter layer of the cup, and the electrode material of the electrode material is used to produce the electrode layer (emitter layer). However, the formation of an electrical layer is not provided by force. Therefore, the present invention is subjected to compression processing after the metal material, and is not peeled off. The metal substrate and the discharge electric power for forming the fluorescent lamp are characterized in that the first de-emitter powder which is compressed on the side of the metal substrate is subjected to removal of the other components. There are a large number of 1314335 λ w pores inside the electrical layer. The pores include voids formed by evaporation of the solvent, air particles entrapped when the powder coating is mixed, and the like. According to the discharge layer formed by the coating step of the present invention, the pores in the discharge layer are crushed and densified by the compression in the first compression step, and the discharge layer is firmly adhered to the metal substrate. Then, in the removing step, components other than the emitter powder such as the dispersion medium are removed to form pores, and the pores are crushed in the second compression step, and the discharge layer is densified again. And because of the second compression step, the thickness of the discharge layer is uniformized, and the discharge layer is more firmly attached to the metal substrate. Such an electrode material for a cold cathode fluorescent lamp can be used to produce a cup-shaped electrode for a cold cathode fluorescent lamp by, for example, plastic working such as deep drawing. At this time, since the discharge layer is densified and firmly adhered to the metal substrate, it is possible to prevent the emitter powder from falling off or peeling off during plastic working. Therefore, for example, the step of the present invention is carried out by continuously winding the metal substrate from the roll (r 11 ), and then it is supplied to the press apparatus for deep drawing to form an electrode or the like, which can be processed in a continuous production line at the factory. Therefore, according to the present invention, not only a discharge layer having a uniform thickness but also a strong adhesion can be formed, and the production efficiency of the electrode for a cold cathode fluorescent lamp can be improved and the production cost can be lowered. The reason why the discharge layer is firmly attached to the metal substrate due to the compression step is not determined. As a result of investigation by the present inventors, it has been confirmed that a part of the emitter powder is bitten into the surface of the metal substrate, which is one of the reasons. It should also be that the emitter powders are separated from each other or the emitter powder and the metal substrate are separated by a residue of the dispersion medium and are not separated by atmospheric pressure. These are merely speculations, and the invention is not limited to the presence or absence of such effects. An electrode was formed from the material produced by the present invention, and when the electrode was used for cold 1314335 cathode fluorescent lamp, the problem of "out gas" inside the glass tube occurred. Therefore, even if there is a residue as described above, it has been confirmed to be harmless. [Embodiment] Fig. 2 is a cross-sectional view showing the steps of the present invention and the state of the discharge layer. In the figure, the symbol 10 is a metal substrate, and the symbol 11 is a discharge layer. As shown in Fig. 2, in the coating step, a surface of the metal substrate 10 is coated with a powder coating of an emitter powder and a dispersion medium (sometimes containing a solvent) to form a slurry, and the powder is dried or cooled. The coating is cured. Thus, the solvent evaporates to form a # vent. This pore is crushed by the first compression step to densify the discharge layer. Secondly, the pores are formed after the dispersion medium is evaporated by the removing step. This pore is crushed by the second compression step to densify the discharge layer. The steps of the present invention are described in detail below. The metal substrate may be nickel (Ni) or nickel alloy (for example, permaloy), iron alloy (for example, stainless steel (stai η 1 essstee 1)), chromium (C r), molybdenum (钽 〇), 钽 (T a), 铌(Nb) a pure metal or an alloy of two or more of these metals. The emitter powder should preferably contain elements with low work function, such as lanthanum tungstate _ (Ba2CaW06, BaW04), calcium hexaboride (CaB6), hexabos saw (SrB6), lanthanum hexaboride (BaB6), hexaboride. LaB6, CeB6, PrB6, NB6, SmB6 One or more of vanadium carbide (VC), chromium carbide (ZrC), niobium carbide (NbC), molybdenum carbide (MoC), carbonized bell (HfC), tantalum carbide (TaC), and tungsten carbide (WC). . The above-mentioned emitter powder and the dispersion medium are mixed into a slurry-like powder coating applied to a metal substrate. The dispersing medium may be a polyvinylidene fluoride 1314335 (polyvinylidene fluoride), an acrylic resin, a phenol resin, a melamine resin, a polyethylene resin, or a polyruthenium resin. A soluble resin such as a polyimide resin, which is natural or synthetically multi-flavored such as hydroxypropylcellulose, methylcellulose or gelatin, and advanced such as ethylenebis stearamide. One or more of the fatty acids are dissolved in a solvent. At this time, the solvent for dissolving the dispersion medium may be an organic solvent such as n-methylpyrrolidone^ or water. The powder coating is preferably prepared by mixing a solvent-containing dispersion medium and a powder in a mass ratio of about 1:1. The drying step is preferably carried out after the coating step to evaporate the solvent. The dispersing medium may be one or more selected from the group consisting of a thermoplastic resin which is heated to a molten state, a natural or synthetic polysaccharide, a metal soap such as zinc stearate, and a higher fatty acid. At this time, energy is saved by solidifying the dispersion medium to room temperature. After the coating step, a cooling step is preferably carried out to cure the dispersion medium. The m w coating step may be any one of a dipping method, a spray method, a printing method, a brush coating method, a flow coating method, and a doctor blade method. The scraper method is a method in which a powder coating is adhered to a metal substrate and scraped to a certain thickness by a doctor blade, and the thickness of the powder coating can be closely controlled. After the powder coating is applied to the metal substrate, it is dried or cooled to be solidified to form a discharge layer on one side of the metal substrate. Next, a first compression step of compressing the discharge layer toward the metal substrate side is performed. In the first compression step, the metal substrate and the discharge layer are sandwiched by a pair of rolls. Thus, the discharge layer is compressed and densely -10-1314335, and the thickness of the discharge layer is uniformized. When the dispersion medium is dissolved in a solvent, the solvent is dried and evaporated to form pores, and the pores are crushed in the first compression step. The compression ratio in the first compression step for the purpose of the present invention is preferably 20% or more. Here, the compression ratio is represented by (ho-hj/ho χ 1 00) when the thickness of the sample before and after compression is hG and hi. Next, the removal step of removing the components other than the emitter powder from the self-discharge layer is performed. Heating is carried out to evaporate the dispersion medium. The heating temperature and time are appropriately selected depending on the type and content of the dispersion medium. Since the heating temperature φ is several hundred ° C, the anti-emitter powder is oxidized, and the removal step is preferably carried out in an inert atmosphere such as nitrogen. Next, a second compression step of compressing the discharge layer toward the metal substrate side is performed. In the second compression step, the metal substrate and the discharge layer are sandwiched by a pair of rolls. After the removal step, the dispersion medium is vaporized and has pores. Forming, and compressing crushes the pores, densifying the discharge layer, and the thickness of the discharge layer is more uniform due to the second compression step. The compression ratio of the second compression step is preferably 50% or more for the purpose of the present invention. Φ 2nd compression After the step, the thickness of the discharge layer should be 0.005~0.05mm. To ensure the discharge characteristics, the thickness of the discharge layer must be above 〇〇5 。5 mm. However, when the thickness of the discharge layer exceeds 0.05 mm, it is easy to form during deep drawing. The electrode material for cold cathode fluorescent lamp manufactured as described above is formed by forming a discharge layer composed of an emitter powder on one surface of a metal substrate. The discharge layer is densified and firmly adhered to the metal substrate, deep drawing When the cup electrode is formed, the discharge layer can be peeled off. The thickness of the discharge layer is uniform in the first and second compression steps, and the discharge characteristics are good when the electrode is used in a cold cathode fluorescent lamp. 1314335 • Example 1 The powder coating of /\砸化钢(LaB6) was applied to one side of a 0.30 mm thick nickel plate at a thickness of 〇.〇2mrn. The powder coating system used samarium hexaboride 47.6 mass%, hydroxypropyl cellulose 2.4 mass%, a mixture of n-methylpyrrolidone 50.0 mass. This sample was heated in air at 12 ° C for 15 minutes to evaporate n-methylpyrrolidone and the powder coating was cured. Secondly, a calendering roll was used at a compression ratio of 25 ° /. 53% was rolled over the above sample # (first compression step). Second, the sample was heated in nitrogen at 500 ° C for 1 hour to evaporate hydroxypropylcellulose. Secondly, calendering was carried out at a compression ratio of 53 % with a calender roll. The above sample (second compression step) [Production Example 1 of the present invention] For comparison, an electrode material for a cold cathode fluorescent lamp (sample 2, sample 3) was produced under the above conditions without performing the first compression step or the second compression step. The sample 2 in the second compression step was subjected to the first compression step, and the discharge layer was peeled off from the metal substrate when the second compression step was performed. 2 • Tape peeling test® The electrode material for the cold cathode fluorescent lamp produced as described above was cut. A test piece was prepared in an appropriate size, and a cellophane tape was attached to the discharge layer, and the tape peeling test was peeled off. The results are shown in Table 1. One of the discharge layers in Table 1 was attached to the cellophane tape and the peeling was evaluated as "△". The stripper of the non-discharge layer was evaluated as "〇". 1314335 Table 1 Compression ratio (%) Tape peeling test wheel 180° buckling test Vibration test 1st compression 2nd compression sample 1 25 53 〇〇〇 _ sample 2 53 Sample 3 53 _ △ 〇〇 As shown in Table 1, The sample of the first and second compression steps was peeled off from the non-discharge layer, and the sample 3 which was not subjected to the second compression step was partially peeled off. ^ The sample 2' which was not subjected to the first compression step was peeled off due to the peeling of the discharge layer in the second compression step, and the tape peeling test could not be performed. 180° buckling test The test piece was bent 180 by the inner side of the discharge layer. The buckling test was carried out to observe the peeling of the discharge layer, and the results are shown in Table 1. As shown in Table 1, the sample 1 in which the first and second compression steps were performed and the sample 3 in which the second compression step was not performed were not peeled off from the discharge layer, and the evaluation was "〇". 4. Excitation test ^ The test piece was placed in a methanol-washed ultrasonic cleaning machine for ultrasonic cleaning for 5 minutes. The peeling of the discharge layer of the test piece after ultrasonic cleaning was observed, and the results are shown in Table 1. As shown in Table 1, the sample 1 in which the first and second compression steps were performed and the sample 3 in which the second compression step was not performed were not peeled off from the discharge layer, and the evaluation was "〇". As described above, in the sample 2 in which the first compression step was not performed, the removed solvent and the pores formed after the dispersion medium disappeared, the discharge layer was in a porous state, and was not resistant to deformation in the second compression step, and the discharge layer collapsed and peeled off. The sample 3 which was not subjected to the 1314335 '2 compression step was formed by the disappearance of the dispersion medium, and the bonding strength between the emitter powders was low, and the tape peeling resistance was poor. Therefore, it has been confirmed that the first and second compression steps are necessary in order to make the discharge layer dense to increase the adhesion strength to the metal substrate. 5 · Internal structure of the discharge layer Fig. 3 is a SEM photograph of the cut surface of the sample 1. From this photograph, it is known that the emitter powders are in close contact with each other. The discharge layer is densified to a few to confirm the absence of pores. It can be confirmed that a part of the emitter powder bites into the surface of the metal substrate. _ 6 · Discharge characteristics The sample 1 was deep drawn to form a cup electrode of the symbol 3 in Fig. 1, and the cold cathode fluorescent lamp of Fig. 1 was produced using the electrode. Other Embodiments of the Invention A cold cathode lamp was produced by substituting hydroxypropylcellulose and n-methylpyrrolidone, and mixing the zinc stearate with the same mass%, and forming an electrode under the conditions of the sample 1. For comparison, an electrode composed of only a nickel plate was formed to produce a cold cathode fluorescent lamp. The current is supplied to the above cold cathode fluorescent lamp to investigate the relationship between current and voltage. The result is shown in Figure 4. ^ It is known from Fig. 4 that the cold cathode fluorescent lamp ' using the electrode produced by the method of the present invention has a lower discharge voltage and better discharge characteristics than a cold cathode fluorescent lamp using an electrode composed only of a nickel plate. It is therefore known that the present invention has exerted the effect of using a low work function emitter powder. This shows an electrode material for a cold cathode fluorescent lamp produced by the present invention, and the discharge layer is not peeled off by elongation stretching. [Simplified description of the drawing] Fig. 1 Structure cutaway view of the cold cathode line lamp. -14- 1314335 Fig. 2 is a sequence diagram showing the steps of an embodiment of the present invention. Figure 3 S EM photograph of the cut surface of the electrode material for cold cathode line lamps. Fig. 4 is a graph showing the relationship between current and voltage of a cold cathode line lamp in an embodiment of the present invention. [Main component symbol description] 10 Metal substrate 11 Discharge layer