201135799 發明說明： 【發明所屬之技術領域】 [0001] [0002] 0 [0003] [0004] ❹ 本發明涉及-種陰轉料的製備方法，尤其涉及一種場 發射陰極漿料的製備方法。 【先前技術】 場發射陰㈣場發㈣件的重要元件。場發射陰極的製 備方法通常為將陰極衆料列印在陰極電極表自，再通過 後續處理方法使陰極發射體從陰極漿料中露出頭來。 以奈米碳Μ料為例，其製備方法包括：在有機溶劑（ 通常為無水乙醇：Μ1超聲分散奈米碳管形成第一混合液 ;在有機溶劑（通常為無水乙醇）中超聲分散玻璃粉和 氧化銦錫顆粒形成第二混合液；將所述第一混合液、第 二混合液及有機載體混合形成一混合物；及在室溫下蒸 發除去有機溶劑。 然而，先刖技術裝備奈米碳管漿料的方法具有以下不足 :第一，奈米碳管漿辑的黏度和塑性释以控制s其原因 在於蒸發除去混合物中的有機溶劑的過程中，需要根據 混合物的量精確地控制蒸發時間和蒸發溫度。如果蒸發 溫度過低或蒸發時間過短就會導致有機溶劑在最後成品 的奈米碳管漿料中有殘餘，從而降低奈米碳管漿料的黏 度和塑性。如果蒸發溫度過高或蒸發時間過長就會導致 有機載體中彿點相對較低的有機載，如松油醇，過量揮 發，這樣最後成品的奈米碳管漿料的黏度和塑性就會上 升。第二，奈米碳管漿料的黏度和塑性不穩定。其原因 在於很難通過蒸發的方法將有機溶劑完全除去。實際使 099111204 表單編號A0101 第3頁/共22頁 0992019713-0 201135799 用過程中，該含有無水乙醇（即便含量很少）的奈米瑞 管漿料在絲網列印過程中，由於乙醇在室溫下很容易揮 發’停留在網板上的奈米碳管聚料會將網板的漏印孔完 全或部分被堵住，既破壞了網印圖案的完整性也造成的 網板的報廢。第三’在有機溶劑中分散奈米碳管、玻璃 粉和氧化銦錫顆粒的過程耗時長，且製備的奈米碳管漿 料成本較高。 【發明内容】 [0005] [0006] [0007] 有鑒於此，提供一種可以有效控制陰極漿料的黏度和塑 座，製備的陰極衆料的黏聲和.塑性穩定，且製備效率較 高，製備成本低廉的陰極漿料的製僙方法實為必要。 種陰極漿料的製備方法’其包括以下步騍：將陰極發 射體，無機黏結劑及有機戟體混合形成一混合物，其中 该有機載體包括稀釋劑、穩定劑和增塑劑；及通過機械 擠壓和剪切作用使上述混令物均勻見合。 -種陰極漿料的製射法，其包如替驟：將奈米碳 管，玻璃粉及有機載體混合形成一混合物，其中該有機 載體包括稀_、敎劑和增㈣卜且歸釋劑為松油 醇’該穩定劑為乙基纖維素，該增塑劑為鄰苯二甲酸二 丁醋或癸二酸二丁 S旨；對所述混合物進行粒度檢測；採 用三輥媒壓機碾壓和剪切該混合物以使該混合物均句混 合；及重複上述步驟直到)、昆合物的粒度小於等於15微米 099111204 相較於先前技術，本發明提供的製備陰極的方法省去了 採用有機溶劑分㈣步驟及祕去除有機溶劑的步驟， 表單編號A0101 第4頁/共22頁 0992019713-0 [0008] 201135799 具有以下優點.第一 ’由於s亥方法不涉及到蒸發去除有 機溶劑這一步驟’故’最終成品陰極漿料的黏度和塑性 就只與各組分的比例有關，故’只要各組分比例—定， 最終陰極漿料的黏度和塑性就可以得到精確控制，其— 致性和重複性都比較好。第二’由於該方法不會引入無 水乙醇等有機溶劑，故，最後成品的陰極漿料室溫下揮 發性很低，在後續的絲網列印過程中不會出現堵網現象 ’既能保證網板圖案轉移的完整性又能實現網板的重複 利用’降低了製備成本。第三，由於該方法不涉及到採 用有機溶劑分散和蒸發去除有機溶劑這一步驟，故，製 備的陰極漿料效率提高，成本降低。 【實施方式】 [0009] 以下將結合附圖詳細說明本發明實施例提供的陰極漿料 的製備方法。 [0010] 本發明實施例提供一種陰極漿料的製備方法，其具體包 括以下步驟： [0011] 步驟-，將陰極發射體，無機黏賴及有機載體混合形 成&物’其中該有機載體包括稀釋劑、穩定劑和增 塑劑。 剛所述陰極發射體包括奈米碳管、奈米碳纖維、金屬奈米 線金屬奈来帶、半導體奈米線及半導體奈米帶中的一 種或多種。可以 Μ理解’任何可以用於發射電子的奈米級 圍之内奉狀或帶狀陰極發射體均包括在本發明的保護範 ^ w所述陰極發射體優選為奈米碳管。所述奈米碳 099111204 綱 米碳管、雙壁奈米碳管及多壁奈米碳管中的 第 5頁/共 22 頁 0992019713-0 201135799 一種或多種。所述單壁奈米破管的直徑為0. 5奈米〜50奈 米，所述雙壁奈米碳管的直徑為1. 0奈米〜50奈米，所述 多壁奈米碳管的直徑為1.5奈米〜50奈米。所述奈米碳管 的長度大於1微米，優選地，所述奈米碳管的長度為5微 米〜1 5微米。 [0013] 所述無機黏結劑包括玻璃粉、二氧化矽粉及氧化錫粉中 的一種或多種。所述玻璃粉為低熔點玻璃粉，其熔點為 300°C~600°C。所述玻璃粉的平均粒徑小於等於10微米 ，優選地，所述玻璃粉的平均粒徑小於等於1微米。 [0014] 所述有機載體為易揮發的有機物，可以通過加熱去除。 其中，所述稀釋劑為陰極漿料提供必要的流淌性，同時 要求對穩定劑具有較好的溶解性。所述穩定劑通常具有 極性較強的基團，可以和增塑劑形成為網狀或鏈狀結構 ，用以提高有機載體的黏度和塑性。所述增塑劑一般為 分子鏈上具有強極性基團的溶劑，其作用為和穩定劑形 成多維網狀結構。所述稀釋劑可以為松油醇，所述穩定 劑可以為乙基纖維素，所述增塑劑可以為鄰笨二甲酸二 丁酯或癸二酸二丁酯。優選地，所述增塑劑為癸二酸二 丁酯。所述癸二酸二丁酯的沸點為344°C，熱揮發特性好 ，且癸二酸二丁酯分子鏈上具有強極性的酯基，可以與 乙基纖維素形成多維網狀結構。由於癸二酸二丁酯的分 子鏈上不含苯環，癸二酸二丁酯為一種綠色環保的增塑 劑。所述癸二酸二丁酯價格低廉，符合絲網列印之大規 模低成本生產要求。進一步，所述有機載體中還還可以 加入少量的表面活性劑，如司班，以提高陰極發射體和 099111204 表單編號A0101 第6頁/共22頁 0992019713-0 201135799 無機黏結劑在有機載體中的分散性。 [0015] 本實施例中，所述陰極發射體為直徑小於等於10奈米且 長度為5微米〜1 5微米的多壁奈米碳管，所述無機黏結劑 為粒徑小於等於10微米的低熔點玻璃粉，所述有機載體 包括乙基纖維素、松油醇、癸二酸二丁酯及司班，且所 述乙基纖維素、松油醇、癸二酸二丁酯和司班的質量比 為11:180:10:2 。 [0016] 所述奈米碳管的質量百分比為2%〜5%，低熔點玻璃粉的質 Ο 量百分比為2%〜5%，有機載體的質量百分比為90%〜96%。 優選地，所述奈米碳管的質量百分比為2. 5%〜3°/。，玻璃粉 的質量百分比為2. 5%〜3%，有機載體的質量百分比為 94%〜95%。可以理解，奈米碳管與玻璃粉的含量過高會導 致奈米碳管漿料的黏度過大，流動性差，不但列印時容 易堵塞絲網而且使列印的圖案邊緣不整齊。而奈米碳管 與玻璃粉的含量過低會導致奈米碳管漿料的可塑性較差 ，不但列印時奈米碳管漿料不易成型且導致列印的圖案 〇 中存在大量孔洞，列印效果差。本發明實施例通過選擇 奈米碳管漿料中各組分的比例，可以確保奈米碳管漿料 具有適合的黏度和可塑性，以滿足列印的要求。 [0017] 本實施例分別製備四組不同比例的奈米碳管漿料樣品， 如表1所示： [0018] 表1不同比例的奈米碳管漿料樣品 [0019] 樣品編號 奈米碳管含量 低熔點玻璃粉 有機載體含量 含量 表單編號A0101 第7頁/共22頁 0992019713-0 099111204 201135799 A 0· 3(克） 0. 3(克） 1〇(克） B 0. 3(克） 〇· 4(克） 1〇(克） C 0· 3(克） 〇· 5(克） 1〇(克） D 〇· 4(克） 0. 4(克） 1〇(克） 本實施例通過機械攪拌使奈米碳管、低熔點玻璃粉及有 機載體混合在一起。所述機械攪拌的時間大約15分鐘。 [0020] 步驟二，通過機械擠壓和剪切作用使上述混合物均勻混 合，形成陰極漿料。 [0021] 所述機械擠壓和剪切作用可以在較小的距離範圍内（如 距離小於等於50微米）對混合物進行作甩，以使得混合 物中的顆粒在混合物中均勻分佈。本實施例中優選地對 混合物進行多次反復機械擠壓和剪切作用，進一步使得 混合物中的顆粒分散均勻，以使上述陰極漿料用於場發 射顯示時亮度均勻，以滿足人眼對顯示器亮度均勻性的 要求。 [0022] 所述通過機械擠壓和剪切作用使上述混合物均勻混合的 步驟可以通過輥壓機、膠體磨、乳化機及捏合機中的一 種或多種相配合實現。本實施例通過一三輥碾壓機碾壓 該混合物，其具體包括以下步驟：對所述混合物進行粒 度檢測；採用三輥碾壓機碾壓該混合物；及重複上述步 驟直到混合物的粒度小於絲網孔徑的1/3。其中，本實施 例採用Model QXD粒度計對所述混合物進行粒度檢測。 所述粒度檢測為檢測混合物中的陰極發射體和無機黏結 劑顆粒的團簇大小。當所述絲網孔徑可為60微米，混合 物的粒度應小於等於20微米以滿足絲網列印要求。本實 099111204 表單編號A0101 第8頁/共22頁 0992019713-0 201135799 [0023] ❹ 〇 [0024] [0025] [0026] 施例中的絲網孔徑為45微米，混合物的粒度應小於等於 1 5微米以滿足絲網列印要求。 請參見圖1，本實施例採用的三輥碾壓機10包括一第一輥 子102，一第二輥子104，一第三輥子106，一進料槽108 ，一出料槽110及電動機（圖未示）等輔助設備。所述第 一輥子102，第二輥子104和第三輥子106依次平行設置 ，且第一輥子102與第二輥子104之間定義一進料口間隙 120，第二輥子104與第三輥子106之間定義一出料口間 隙122 〇所述進料槽108設置於所述進料口間隙120上方 。所述出料槽110設置於所述第三輥子106遠離第二輥子 104的一側。所述三輥碾壓機10工作時，第一輥子102， 第二輥子104和第三輥子106的旋轉方向如圖1所示。所 述混合物112從進料口間隙120進入，經第一輥子102與 第二輥子104碾壓後被第二輥子104帶到出料口間隙122 ，再經第二輥子104和第三輥子106碾壓後，由出料槽 110進入一容器114。 本實施例採用三輥碾壓機10在間隙工作模式下碾壓該混 合物112，其具體包括以下步驟： 首先，調節進料口間隙120和出料口間隙122，使進料口 間隙120的寬度與混合物的平均粒度相同，並使出料口間 隙122的寬度為進料口間隙120寬度的1/4至1/2。本實施 例優選地所述出料口間隙12 2的寬度優選為進料口間隙 120寬度的1/3。 其次，將混合物112放入進料槽108，並使三輥碾壓機10 099111204 表單編號Α0101 第9頁/共22頁 0992019713-0 201135799 工作，開始碾壓混合物112。本實施例中，所述三輥碾壓 機10的三個棍子的旋轉速率為150 rpm~20 0rpm，優選 為20Orpm。所述混合物11 2經過碾壓後，從出料槽110進 入容器114。 [0027] 然後，對碾壓後的混合物112進行粒度測試後，重複上述 步驟，直到混合物11 2的粒度不再減小。 [0028] 最後，調節進料口間隙120和出料口間隙122的寬度至最 小值，並反復多次碾壓該混合物112，直到混合物112的 粒度基本不變。本實施例中，所述進料口間隙120和出料 口間隙122的寬度最小值均為5微米，並在最小間隙模式 下重複碾壓3次~7次該混合物112。 [0029] 可以理解，所述通過機械擠壓和剪切作用使混合物均勻 混合的步驟前還可以進一步包括一向混合物中加入導電 顆粒的步驟。 [0030] 所述導電顆粒包括氧化銦錫顆粒及金屬顆粒等中的一種 或多種。所述金屬顆粒包括金顆粒、銀顆粒、銘顆粒及 銅顆粒等中的一種或多種。所述金屬顆粒優選為銀顆粒 或鋁顆粒。所述導電顆粒的直徑為100奈米〜10微米，優 選為10奈米〜100奈米。 [0031 ] 本發明實施例對上述奈米碳管漿料樣品分別進行黏度測 試。本發明實施例提供的奈米碳管漿料在剪切速率為10/ 秒時的黏度為13Pa . s〜16Pa · s。請參閱圖2，為本發明 實施例提供的奈米碳管漿料樣品A的黏度測試結果。由圖 2可見，本發明實施例提供的奈米碳管漿料的黏度隨著剪 099111204 表單編號A0101 第10頁/共22頁 0992019713-0 201135799 切速率的增大而減小，故，該奈米碳管漿料為假塑型流 體，非常適合列印的要求。 [0032] Ο Ο 進一步，本發明實施例對奈米碳管漿料樣品Β的場發射的 亮度均勻性進行了測試。本發明實施例採用奈米碳管漿 料樣品Β製備在玻璃基板上列印8x8個（8行，每行8個） 場發射單元，並封裝成一場發射顯示器。其中，每個發 光小方塊的尺寸為5毫米χ5毫米。本發明實施例分別在低 電壓和高電壓下對該場發射顯示器的亮度均勻性進行了 測試，其中低電壓時的電壓為3150V，電流為2. 5mA/cin2 ，高電壓時的電壓為4160V，電流為10mA/cm2，。請參 閱圖3和圖4，為該場發射顯示器的顯示效果照片。由圖3 和圖4可見，採用奈米碳管漿料樣品B製備的場發射顯示 器的發光均勻性好，人眼沒有明顯的亮暗差異，可以滿 足大螢幕顯示的均勻性要求。請參閱圖5和圖6，分別為 圖3和圖4的場發射顯示器對應的場發射顯示亮度值。由 圖5和圖6可見，在低電壓下，64個發光點顯示亮度的均 值為27. 93cd/m2，最亮為30. 01 cd/m2，最暗為25. 12 cd/m2，明暗最大差異為17. 51%;在高電壓下，64個發 光點顯示亮度的均值為144. 79 cd/m2,最亮為152. 6 cd/m2，最暗為136 cd/m2，明暗最大差異為11. 46%。 由此可見，本發明實施例對奈米碳管漿料在高低電場下 場發射顯示均勻，人眼沒有明顯的明暗差異，完全可以 滿足顯示的均勻性要求。 本發明提供的製備陰極的方法省去了採用有機溶劑分散 陰極發射體和無機黏結的步驟及蒸發去除有機溶劑的步 099111204 表單編號A0101 第11頁/共22頁 0992019713-0 [0033] 201135799 [0034] [0035] [0036] [0037] [0038] 驟’具有以下優點：第―，由於該方法*涉及到蒸發去 除有機溶劑這一步驟，故，最終成品陰極漿料的黏度和 塑性就只與各組分的比例有關，故，只要各組分比例一 疋，最終陰極漿料的黏度和塑性就可以得到精確控制， 其—致性和重複性都比較好。第二，由於該方法不會引 入無水乙醇等有機溶劑，故，最後成品的陰極襞料室溫 下揮發性很低’在後續的_列印過程中不會出現堵網 現象，既能保證網板圖案轉移的完整性又能實現網板的 重複利用’降低了製備成本。第三，由於該方法不涉及 到如用有機溶劑分散和蒸發去除有機落劑這一步驟故 ，製備的陰極漿料效率提高，成本降低。 综上所述，本發明確已符合發明專利之要件，遂依法提 出專利申请。惟，以上所述者僅為本發明之較佳實施例 ，自不能以此限制本案之申請專利範圍。舉凡熟悉本案 技藝之人士援依本發明之精神所作之等效修飾或變化， 皆應涵蓋於以下申請專利範齒内。 , 【®式簡單說明】 圖1本發明實施例採用的三輥碾壓機的結構示意圖及採用 該三輥碾壓機碾壓混合物的工作過程示意圖。 圖2為本發明實施例製備的奈米碳管漿料的黏度測試結果 〇 圖3為採用本發明實施例製備的奈米碳管漿料的場發射顯 示器在低電壓下工作的顯示效果照片。 圖4為採用本發明實施例製備的奈米碳管漿料的場發射顯 099111204 表單蝙號A0101 第12頁/共22頁 0992019713-0 201135799 示器在高電壓下工作的顯示效果照片。 [0039] 圖5為採用本發明實施例製備的奈米碳管漿料的場發射顯 示器在低電壓下工作時的場發射顯示亮度值。 [0040] 圖6為採用本發明實施例製備的奈米碳管漿料的場發射顯 示器在高電壓下工作時的場發射顯示亮度值。201135799 Description of the Invention: [Technical Field] [0001] The present invention relates to a method for preparing a negative transfer material, and more particularly to a method for preparing a field emission cathode slurry. [Prior Art] An important component of the field emission (four) field (four) pieces. The field emission cathode is usually prepared by printing a cathode mass on the cathode electrode surface and then exposing the cathode emitter from the cathode slurry by a subsequent treatment. Taking the nanocarbon carbon as an example, the preparation method comprises the steps of: forming a first mixture in an organic solvent (usually anhydrous ethanol: Μ1 ultrasonically dispersed carbon nanotubes; and ultrasonically dispersing the glass powder in an organic solvent (usually anhydrous ethanol) Forming a second mixed liquid with indium tin oxide particles; mixing the first mixed liquid, the second mixed liquid and the organic vehicle to form a mixture; and evaporating and removing the organic solvent at room temperature. However, the first technique is equipped with nano carbon. The method of pipe slurry has the following disadvantages: First, the viscosity and plastic release of the carbon nanotube slurry are controlled because the evaporation time is accurately controlled according to the amount of the mixture in the process of evaporating and removing the organic solvent in the mixture. And evaporation temperature. If the evaporation temperature is too low or the evaporation time is too short, the organic solvent will remain in the final finished carbon nanotube slurry, thereby reducing the viscosity and plasticity of the carbon nanotube slurry. If the evaporation time is too long or too long, the organic carrier will have a relatively low organic loading, such as terpineol, which is excessively volatilized, so that the final finished nanocarbon The viscosity and plasticity of the tube slurry will increase. Second, the viscosity and plasticity of the carbon nanotube slurry are unstable. The reason is that it is difficult to completely remove the organic solvent by evaporation. Actually, 099111204 Form No. A0101 No. 3 Page / Total 22 pages 0992019713-0 201135799 In the process, the nano-barrel slurry containing anhydrous ethanol (even if the content is very small) in the screen printing process, because ethanol is easily volatilized at room temperature 'stay in The carbon nanotubes on the stencil will completely or partially block the stencil hole of the stencil, which will destroy the integrity of the screen printing pattern and also cause the stencil to be scrapped. The third 'dispersed in organic solvent The process of the carbon nanotubes, the glass frit and the indium tin oxide particles takes a long time, and the prepared carbon nanotube slurry has a high cost. [0007] [0007] [0007] In view of this, a The method can effectively control the viscosity and plastic seat of the cathode slurry, and the preparation of the cathode mass is stable and the plasticity is stable, and the preparation efficiency is high, and the preparation method of the cathode slurry with low preparation cost is really necessary. Preparation method' The method comprises the steps of: mixing a cathode emitter, an inorganic binder and an organic steroid to form a mixture, wherein the organic carrier comprises a diluent, a stabilizer and a plasticizer; and the above mixing is performed by mechanical extrusion and shearing The uniformity of the material is as follows: a method for preparing a cathode slurry, which comprises a step of mixing: a carbon nanotube, a glass powder and an organic carrier are mixed to form a mixture, wherein the organic carrier comprises a rare sputum, a sputum agent and an increase (four) And the release agent is terpineol', the stabilizer is ethyl cellulose, the plasticizer is dibutyl phthalate or dibutyl phthalate; the mixture is tested for particle size; three rolls are used. The press presses and shears the mixture to uniformly mix the mixture; and repeats the above steps until), the particle size of the clathrate is less than or equal to 15 microns 099111204. Compared with the prior art, the method for preparing a cathode provided by the present invention is omitted. Go to the step of using organic solvent (4) and remove the organic solvent. Form No. A0101 Page 4 / Total 22 Page 0992019713-0 [0008] 201135799 has the following advantages. The first 'because s Hai method does not involve The step of removing the organic solvent is as follows. Therefore, the viscosity and plasticity of the final finished cathode slurry are only related to the ratio of each component. Therefore, as long as the ratio of each component is determined, the viscosity and plasticity of the final cathode slurry can be obtained. Precise control, which is both good and repeatable. Secondly, since the method does not introduce an organic solvent such as anhydrous ethanol, the final cathode slurry has low volatility at room temperature, and no blocking phenomenon occurs in the subsequent screen printing process. The integrity of the stencil pattern transfer enables the reuse of the stencil' to reduce the manufacturing cost. Third, since the method does not involve the step of removing the organic solvent by organic solvent dispersion and evaporation, the prepared cathode slurry is improved in efficiency and cost. [Embodiment] Hereinafter, a method for preparing a cathode slurry according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings. [0010] Embodiments of the present invention provide a method for preparing a cathode slurry, which specifically includes the following steps: [0011] Step--mixing a cathode emitter, an inorganic binder, and an organic carrier to form an & ', wherein the organic carrier includes Thinners, stabilizers and plasticizers. The cathode emitter just includes one or more of a carbon nanotube, a nanocarbon fiber, a metal nanowire, a semiconductor nanowire, and a semiconductor nanobelt. It is to be understood that any semiconductor or ribbon cathode emitter that can be used to emit electrons is included in the protection of the present invention. The cathode emitter is preferably a carbon nanotube. One or more of the nanocarbon 099111204 carbon nanotubes, double-walled carbon nanotubes, and multi-walled carbon nanotubes. Page 9 of 22 0992019713-0 201135799. The nano-walled carbon nanotubes having a diameter of 0.5 nm to 50 nm, and the double-walled carbon nanotubes having a diameter of 1.0 nm to 50 nm, the multi-walled carbon nanotubes The diameter is from 1.5 nm to 50 nm. The length of the carbon nanotubes is greater than 1 micron. Preferably, the length of the carbon nanotubes is from 5 micrometers to 15 micrometers. [0013] The inorganic binder includes one or more of glass frit, cerium oxide powder, and tin oxide powder. The glass frit is a low-melting glass frit having a melting point of 300 ° C to 600 ° C. The glass frit has an average particle diameter of 10 μm or less, and preferably, the glass frit has an average particle diameter of 1 μm or less. [0014] The organic vehicle is a volatile organic substance and can be removed by heating. Among them, the diluent provides the necessary flowability to the cathode slurry, and at the same time requires better solubility to the stabilizer. The stabilizer generally has a more polar group and can be formed into a network or chain structure with a plasticizer to increase the viscosity and plasticity of the organic carrier. The plasticizer is generally a solvent having a strong polar group on the molecular chain, and functions to form a multidimensional network structure with the stabilizer. The diluent may be terpineol, the stabilizer may be ethyl cellulose, and the plasticizer may be dibutyl ortho-dicarboxylate or dibutyl sebacate. Preferably, the plasticizer is dibutyl sebacate. The dibutyl sebacate has a boiling point of 344 ° C, good thermal volatility, and a highly polar ester group on the molecular chain of dibutyl sebacate, which can form a multidimensional network structure with ethyl cellulose. Since the molecular chain of dibutyl sebacate does not contain a benzene ring, dibutyl sebacate is a green plasticizer. The dibutyl sebacate is inexpensive and meets the large-scale, low-cost production requirements for screen printing. Further, a small amount of a surfactant may be added to the organic carrier, such as Siban, to enhance the cathode emitter and 099111204. Form No. A0101 Page 6 of 22 0992019713-0 201135799 Inorganic binder in an organic vehicle Dispersibility. [0015] In this embodiment, the cathode emitter is a multi-walled carbon nanotube having a diameter of 10 nm or less and a length of 5 μm to 15 μm, and the inorganic binder has a particle diameter of 10 μm or less. a low-melting glass frit, the organic vehicle comprising ethyl cellulose, terpineol, dibutyl sebacate and syrup, and the ethyl cellulose, terpineol, dibutyl sebacate and siban The mass ratio is 11:180:10:2. [0016] The mass percentage of the carbon nanotubes is 2% to 5%, the percentage of mass of the low-melting glass powder is 2% to 5%, and the mass percentage of the organic vehicle is 90% to 96%. 5%〜3°/。 The mass percentage of the carbon nanotubes is 2. 5% ~ 3 ° /. The mass percentage of the glass frit is 2.5% to 3%, and the mass percentage of the organic vehicle is 94% to 95%. It can be understood that the excessive content of the carbon nanotubes and the glass powder causes the viscosity of the carbon nanotube slurry to be too large, and the fluidity is poor, which not only causes the screen to be clogged easily when printed, but also causes the edges of the printed pattern to be irregular. The low content of carbon nanotubes and glass powder will result in poor plasticity of the carbon nanotube slurry. Not only the nanocarbon tube slurry is not easy to be formed when printing, but also a large number of holes in the printed pattern, printing poor effect. In the embodiment of the present invention, by selecting the proportion of each component in the carbon nanotube slurry, it is ensured that the carbon nanotube slurry has a suitable viscosity and plasticity to meet the printing requirements. [0017] In this example, four sets of different proportions of carbon nanotube slurry samples were prepared, as shown in Table 1: [0018] Table 1 different proportions of carbon nanotube slurry samples [0019] sample number nano carbon Tube content low melting point glass powder organic carrier content content form No. A0101 Page 7 / Total 22 pages 0992019713-0 099111204 201135799 A 0 · 3 (g) 0. 3 (g) 1 〇 (g) B 0. 3 (g) 〇·4(g) 1〇(g) C 0· 3(g) 〇·5(g) 1〇(g) D 〇·4(g) 0. 4(g) 1〇(g) This embodiment The carbon nanotubes, the low-melting glass frit and the organic vehicle are mixed together by mechanical stirring. The mechanical agitation time is approximately 15 minutes. [0020] In the second step, the above mixture is uniformly mixed by mechanical pressing and shearing to form a cathode slurry. [0021] The mechanical extrusion and shearing action can effect the mixture in a small distance range (e.g., a distance of 50 microns or less) so that the particles in the mixture are evenly distributed throughout the mixture. In the present embodiment, the mixture is preferably subjected to repeated mechanical extrusion and shearing operations to further uniformly disperse the particles in the mixture, so that the cathode slurry is used for field emission display with uniform brightness to meet the human eye. Requirements for brightness uniformity. [0022] The step of uniformly mixing the above mixture by mechanical pressing and shearing can be carried out by one or more of a roll press, a colloid mill, an emulsifier, and a kneader. In this embodiment, the mixture is crushed by a three-roll mill, which specifically comprises the steps of: performing particle size detection on the mixture; rolling the mixture with a three-roll mill; and repeating the above steps until the particle size of the mixture is smaller than that of the wire. 1/3 of the mesh aperture. Among them, this example uses a Model QXD granulometer to perform particle size detection on the mixture. The particle size detection is to detect the cluster size of the cathode emitter and the inorganic binder particles in the mixture. When the screen aperture is 60 microns, the particle size of the mixture should be less than or equal to 20 microns to meet the screen printing requirements.本实099111204 Form No. A0101 Page 8 / Total 22 Page 0992019713-0 201135799 [0023] [0024] [0026] The mesh aperture in the embodiment is 45 microns, and the particle size of the mixture should be less than or equal to 15 Micron to meet screen printing requirements. Referring to FIG. 1, the three-roll roller compactor 10 used in this embodiment includes a first roller 102, a second roller 104, a third roller 106, a feed slot 108, a discharge slot 110 and an electric motor (Fig. Auxiliary equipment such as not shown. The first roller 102, the second roller 104 and the third roller 106 are sequentially disposed in parallel, and a feed port gap 120 is defined between the first roller 102 and the second roller 104, and the second roller 104 and the third roller 106 are A discharge port gap 122 is defined therebetween. The feed chute 108 is disposed above the feed port gap 120. The discharge chute 110 is disposed on a side of the third roller 106 away from the second roller 104. When the three-roll mill 10 is in operation, the directions of rotation of the first roller 102, the second roller 104, and the third roller 106 are as shown in FIG. The mixture 112 enters from the feed port gap 120, is crushed by the first roller 102 and the second roller 104, is carried by the second roller 104 to the discharge port gap 122, and is then ground by the second roller 104 and the third roller 106. After pressing, a container 114 is introduced from the discharge chute 110. In this embodiment, the three-roll mill 10 is used to crush the mixture 112 in the gap working mode, which specifically includes the following steps: First, the feed port gap 120 and the discharge port gap 122 are adjusted to make the width of the feed port gap 120 The average particle size is the same as the mixture, and the width of the discharge port gap 122 is 1/4 to 1/2 of the width of the feed port gap 120. Preferably, the width of the discharge opening 12 2 is preferably 1/3 of the width of the feed opening gap 120 in this embodiment. Next, the mixture 112 is placed in the feed tank 108, and the three-roll mill 10 099111204 Form No. Α0101 Page 9 of 22 0992019713-0 201135799 is operated to start rolling the mixture 112. In the present embodiment, the three sticks of the three-roll mill 10 have a rotation rate of 150 rpm to 20 rpm, preferably 20 rpm. After the mixture 11 2 is crushed, it is introduced into the vessel 114 from the discharge tank 110. [0027] Then, after the particle size test of the milled mixture 112, the above steps are repeated until the particle size of the mixture 11 2 is no longer reduced. Finally, the widths of the feed port gap 120 and the discharge port gap 122 are adjusted to a minimum value and the mixture 112 is repeatedly crushed until the particle size of the mixture 112 is substantially constant. In this embodiment, the minimum width of the feed port gap 120 and the discharge port gap 122 are both 5 micrometers, and the mixture 112 is repeatedly rolled 3 times to 7 times in the minimum gap mode. It will be understood that the step of uniformly mixing the mixture by mechanical extrusion and shearing may further comprise the step of adding conductive particles to the mixture. [0030] The conductive particles include one or more of indium tin oxide particles, metal particles, and the like. The metal particles include one or more of gold particles, silver particles, ingot particles, and copper particles. The metal particles are preferably silver particles or aluminum particles. The conductive particles have a diameter of from 100 nm to 10 μm, preferably from 10 nm to 100 nm. [0031] In the embodiment of the invention, the carbon nanotube slurry samples were respectively subjected to a viscosity test. The viscosity of the carbon nanotube slurry provided by the embodiment of the present invention at a shear rate of 10/sec is 13 Pa.s~16 Pa·s. Please refer to FIG. 2 , which is a viscosity test result of the sample A of the carbon nanotube slurry provided by the embodiment of the present invention. It can be seen from FIG. 2 that the viscosity of the carbon nanotube slurry provided by the embodiment of the present invention decreases as the cutting rate of the 099111204 form number A0101 is increased, so the The carbon nanotube slurry is a pseudo-plastic fluid that is ideal for printing. Further, the embodiment of the present invention tested the brightness uniformity of the field emission of the carbon nanotube slurry sample enthalpy. In the embodiment of the present invention, 8x8 (8 rows, 8 rows per row) field emission units are printed on a glass substrate by using a carbon nanotube slurry sample, and packaged into a field emission display. Among them, each light-emitting small square has a size of 5 mm χ 5 mm. The embodiment of the present invention tests the brightness uniformity of the field emission display at a low voltage and a high voltage, wherein the voltage at a low voltage is 3150 V, the current is 2. 5 mA/cin 2 , and the voltage at a high voltage is 4160 V. The current is 10 mA/cm2. Please refer to Fig. 3 and Fig. 4 for the display effect photo of the field emission display. It can be seen from Fig. 3 and Fig. 4 that the field emission display prepared by using the carbon nanotube slurry sample B has good uniformity of illumination, and the human eye has no obvious difference in brightness and darkness, and can meet the uniformity requirement of the large screen display. Referring to Figures 5 and 6, the field emission display brightness values corresponding to the field emission displays of Figures 3 and 4, respectively. It can be seen from Fig. 5 and Fig. 6 that, at a low voltage, the average brightness of the 64 light-emitting points is 27.93 cd/m2, the brightest is 30. 01 cd/m2, and the darkest is 25.12 cd/m2, and the brightness is the largest. The difference is 17.51%; at high voltage, the average of the brightness of 64 light-emitting points is 144.79 cd/m2, the brightest is 152.6 cd/m2, the darkest is 136 cd/m2, and the maximum difference between light and dark is 11. 46%. It can be seen that the embodiment of the present invention shows uniform emission of the carbon nanotube slurry under high and low electric fields, and there is no obvious difference in brightness between the human eye and the display uniformity requirement. The method for preparing a cathode provided by the present invention eliminates the step of dispersing a cathode emitter and an inorganic binder by using an organic solvent and the step of evaporating and removing an organic solvent. 099111204 Form No. A0101 Page 11 / Total 22 Page 0992019713-0 [0033] 201135799 [0034 [0038] [0038] [0038] The step 'has the following advantages: ―, since the method* involves the step of evaporating the organic solvent, the viscosity and plasticity of the final finished cathode slurry are only The proportion of each component is related. Therefore, as long as the ratio of each component is one, the viscosity and plasticity of the final cathode slurry can be precisely controlled, and the consistency and repeatability are better. Second, since the method does not introduce an organic solvent such as anhydrous ethanol, the final cathode bismuth has a low volatility at room temperature, and there is no blocking phenomenon in the subsequent printing process. The integrity of the plate pattern transfer enables the reuse of the stencil' to reduce the manufacturing cost. Third, since the method does not involve the step of removing the organic falling agent by dispersing and evaporating with an organic solvent, the prepared cathode slurry is improved in efficiency and cost. In summary, the present invention has indeed met the requirements of the invention patent, and the patent application is filed according to law. However, the above description is only a preferred embodiment of the present invention, and it is not possible to limit the scope of the patent application of the present invention. Equivalent modifications or variations made by persons skilled in the art in light of the spirit of the invention are intended to be included in the following claims. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic view showing the structure of a three-roll mill used in the embodiment of the present invention and a working process of compacting a mixture using the three-roll mill. Fig. 2 is a viscosity test result of a carbon nanotube slurry prepared in an embodiment of the present invention. Fig. 3 is a photograph showing a display effect of a field emission display of a carbon nanotube slurry prepared by using an embodiment of the present invention at a low voltage. 4 is a field emission display of a carbon nanotube slurry prepared by using an embodiment of the present invention. 099111204 Form bat No. A0101 Page 12 of 22 0992019713-0 201135799 A photograph showing the effect of the display working at a high voltage. 5 is a field emission display luminance value when a field emission display of a carbon nanotube slurry prepared by using an embodiment of the present invention operates at a low voltage. [0039] FIG. 6 is a field emission display luminance value when a field emission display of a carbon nanotube slurry prepared by using an embodiment of the present invention operates at a high voltage. [0040] FIG.
[0041] 【主要元件符號說明】 三輥碾壓機：10 [0042] 第一輥子：102 [0043] 第二輥子：104 [0044] 第三輥子：106 [0045] 進料槽：108 [0046] 出料槽：110 [0047] 混合物：112 [0048] 容器：114 [0049] 進料口間隙：1 20 [0050] 出料口間隙：12 2 099111204 表單編號A0101 第13頁/共22頁 0992019713-0[Main component symbol description] Three-roll mill: 10 [0042] First roller: 102 [0043] Second roller: 104 [0044] Third roller: 106 [0045] Feeding tank: 108 [0046] Discharge tank: 110 [0047] Mixture: 112 [0048] Container: 114 [0049] Feed gap: 1 20 [0050] Outlet gap: 12 2 099111204 Form number A0101 Page 13 of 22 0992019713 -0