200424129 九、發明說明： 【發明所屬之技術領域】 本發明係有關於一種鈦酸鋇粉末的製造方法，特別是 有關於一種適用於介電體材料之鈦酸鋇粉末的製造方法， ‘ · · · 該介電體材料具有粒徑1 // m以下之高結晶性鈣鈦礦 (perovskite)結構。 【先前技術】 因爲積層陶瓷電容器所使用之介電體材料，要求在高 介電常數下溫度特性好、以及偏壓依賴性低、耐電壓性優 良，所以以往廣泛地使用鈦酸鋇系的組成物。 一般而言，積層陶瓷電容器可以如以下進行製造。亦 即，使鈦酸鋇等之介電體粉末與有機膠黏劑混合、懸浮， 使用刮刀（doctor blade)將其形成片狀而製成綠片（green sheet)。接著，將內部電極用之金屬粉末與有機溶劑、可塑 劑、有機膠黏劑等有機化合物混合、形成金屬粉末膏，使 用絲網印刷法將其印刷於上述之印刷電路基板上。接著， 對此等進行乾燥、交錯地積層壓貼，在大氣中以3 00°C程度 加熱處理來去除有機成分後，以°C以上的溫度進行燒 結。最後，在介電體陶瓷層之兩端鍍上外部電極後得到疊 層陶瓷電容器。此燒結溫度，一般而言鉛系爲10〇〇°C左右 ，鈦酸鋇系之介電體磁器組成物’因爲燒結特性不同’必 須在約爲1 3 0 0 °C左右、或是比這更高的溫度進行。如此’ 積層陶瓷電容器之製造，同時進行燒結介電體層及內部金 屬層。 200424129 如此’構成積層陶瓷電容器之內部電極金屬層所使用 之金屬，以往係使用銀、鈀、鉑、金等之貴金屬粉末，或 是使用鎳、鈷、鐵、鉬、鎢等賤金屬粉末，因爲最近要求 使用更便宜的電子材料，利用上述賤金屬粉末來開發積層 陶瓷電容器正積極地進行著。上述積層陶瓷電容器之製造 步驟中，使用貴金屬粉末作爲內部電極時，燒結亦可以在 氧氣環境中進行。但是，若使用如鎳之類的賤金屬粉末作 爲內部電極時，在高溫大氣中之氧化作用環境下會有氧化 物導致絕緣性增高之虞，因此，此種情況必須在氫氣等還 原性環境進行燒結。 如上述，積層陶瓷電容器之製造步驟，藉由在大氣中 加熱處理來去除有機成分，而且，鎳電極時，在還原性環 境下進行燒結時所產生的氧化還原，金屬粉末會因爲膨脹 、收縮而產生體積變化。另一方面，介電體自身亦因爲燒 結而產生體積變化，但是因爲係同時燒結屬於不同物質之 介電體和金屬粉末，在燒結過程中各自物質之體積變化（膨 脹、收縮）等之燒結舉動不同。因此，金屬膏層發生變形， 結果發生所謂龜裂或是剝離等分層’而有層間結構體被破 壞之結構缺陷問題存在。於是要求介電材料盡可能能夠在 低溫燒結。 又，因爲介電體材料係氧化物’以往係使用可以與大 氣中之氧保持平衡狀態之材料。但是製造如上述鎳電極積 層陶瓷電容器時，係在環原性還境下進行燒結’因而’此 時所使用的介電體材料在氧分壓低之狀態下被還原，必須 200424129 使用不會半導體化之具有耐還原性之物才可以。 因此’以往鑑於此必要性，已進行檢討許多非還原性 介電體磁器組成物，例如，在主成分之鈦酸鋇中調配副成 分之釔等稀土類原子及鎂、錳、矽等氧化物所燒成之物， 被利用當作積層陶磁電容器之介電體。 關於如此的積層陶瓷電容器之習知技術，在改良介電 體材料耐還原性、低溫燒結性之同時，亦滿足X7R特性、 更在高溫負荷特性友偏壓特性等達成相當的效果。但是， 近年來’隨著行動電話或是個人電腦等之顯著小型化以及 要求大電容量化’亦要求積層陶瓷電容器薄層化，目前該 要求厚度爲以下、越來越薄層化。但是，介電體層 薄化時，會有內部電極間絕緣耐壓降低之問題存在。進而 ，從節省能源觀點要求能夠節省電力，因此，希望能夠開 發一種在室溫以上時介電損失少而且發熱較少的介電體材 料。 又’積層陶瓷電容器除了薄層化之外亦快速朝向小型 化及大電容量化邁進，這時，必須耐電壓特性良好、介電 體材料自身的粒徑小、層密度均一，而且必須可以確保充 分的電容器容量。 如此’爲了滿足近年來之要求特性，己有種種的開發 技術提案’特別是關於作爲該原料之鈦酸鋇粉末的製造方 法，已知有各種製造方法。鈦酸鋇粉末的製造方法，大致 可以分類爲鈦化合物與鋇化合物混合燒成之固相反應法、 和使水溶性鈦化合物與水溶性鋇化合物在液相反應之液相 200424129 反應法。上述固相反應法，因爲係使化合物在高溫進行反 應，所得到之鈦酸鋇粉末粒徑較大、粒度分布較廣，而且 形狀並非一定，所以有在漿液（slurry)化時分散性差之問題 存在。爲了解決該問題，有揭示一種鈦酸鋇粉末之製造方 法（例如，參照日本特開平1 0 -3 3 8 5 24號公報（專利文獻1)) ’其特徵爲，具備有選擇比表面積爲l〇m2/g以下之BaC03 粉末及比表面積爲15m2/g以上之Ti02粉末之選擇步驟、和 混和此等BaC03粉末與Ti02粉末之混合步驟、和將燒成此 等混合物之燒成步驟。 又，液相反應法有揭示一種使水合氧化鈦、鋇氯化物 和硝酸鹽之至少其中之一、和鋇氯化物及/或硝酸鹽lmol， 與2.1〜5mol之鹼金屬氫氧化物在60M 10°C下，在換算鈦爲 1 20〜1 0000倍mol之水的存在下進行反應之製造方法（例如 ，參照日本專利特公平5 -73 6 95號公報（專利文獻2)，亦有 揭示一種使水合氧化鈦、氫氧化鋇及鹼金屬氫氧化物，在 換算鈦爲120〜1 0000倍m〇l之水的存在下，於60〜110°C進 行反應之製造方法（例如，參照日本專利特公平5-73 696號 公報（專利文獻3))，亦有揭示一種使鈦化合物之加水分解 生成物和水溶性鋇鹽在強鹼水溶液中反應之製造方法（例如 ，參照日本專利特公平3-3 90 1 4號公報（專利文獻4))。又 ，亦有揭示一種使鈦氯化物在水溶液中加水分解後，使該 水溶液一時回復鹼性而去除氯離子，接著加入鋇水溶性鹽 之其中之一’使在強鹼性水溶液中進行反應之製造方法（例 如，參照日本專利特公平6-649號公報（專利文獻5))，亦 200424129 有揭示一種使四氯化鈦等鈦化合物和鋇鹽共存之混合溶液 ，與預熱至7 〇〜1 〇 〇 °c之鹼水溶液接觸而得到大約爲球狀之 結晶性鈣鈦礦（perovskite)結構物之方法（例如，參照日本 專利特開平7-2 3 2923號公報（專利文獻6))。又，亦有揭示 一種鈦酸鋇粉之製造方法，其特徵爲，邊控制鈦化合物/鋇 化合物之m ο 1比在0 · 8〜1 · 2，邊在攪拌之下使鈦化合物之水 溶液和鋇化合物之鹼水溶液接觸（例如，參照日本專利國際 公開W099/599 1 9號公報（專利文獻7)。此外，亦有揭示一 種.鍛燒液相反應法所得到之鈣鈦礦型化合物粉末後，以酸 溶液進行洗淨（例如，參照日本專利特許第2 9 9 9 8 2 1號公報 (專利文獻8))。 但是，上述日本專利特許文獻1〜7所記載之各技術， 關於以往成爲問題之耐電壓特性、燒製完成後之粒子非凝 聚特性、層密度之均勻特性及充分確保電容器之容量等之 特性，雖然已得某種程度的改善，但是在形成介電體時之 介電損失及溫度特性等介電特性上，仍然不是已達到可以 滿足地符合近年來積層陶瓷電容器之介電體層因薄膜化之 小型化以及大電容量化之物。 又’上述日本專利特許文獻8所述之技術，爲了洗淨 鍛燒後之鈣鈦礦型化合物粉末，鈦酸鋇之情況，鋇成分會 過剩而溶出，不容易控制精確度在鋇原子和鈦原子比爲1 〇 〇 分之1〜1 000分之1。 本發明針對上述日本專利文獻1〜8所述鈦酸鋇粉末所 附帶之課題，亦即，本發明之目的係提供一種鈦酸鋇粉末 -9- 200424129 之更簡便的製造方法，該鈦酸鋇粉末在形成介電體時具有 優良的介電損失及溫度特性。 【發明內容】 本發明者等，鑽硏檢討可以達成上述目的之製造方法 ’結果發現藉由對上述固相反應法和液相反應法所得到之 鈦酸鋇粉末進行加熱處理，接著進行水洗，可以得到在形 成介電體時具有優良的介電特性之鈦酸鋇粉末，終於完成 了本發明。 本發明之鈦酸鋇粉末之製造方法，其特徵爲，對藉由 使鈦化合物和鋇化合物接觸所得到之固體成分，以800〜1 100 °c進行加熱處理該固體成分來形成固體反應物，其後對前 述固體反應物進行水洗。依照本發明，對固相反應法或是 液相反應法所得到之鈦酸鋇粉末進行加熱處理後進行水洗 ，可得到在形成介電體時具有優良的介電特性之鈦酸鋇粉 末。 又，本發明之鈦酸鋇之製造方法，上述之水洗爲2(TC〜80 °C、以30°C〜70°C爲佳，更佳的是在40°C〜60°C之範圍進行， 對提升洗淨效率是有效果的。 如此的鈦酸鋇粉末之製造方法，固體反應物之形成， 可以對在鹼之存在下使鈦化合物化合物水溶液和鋇化合物 接觸所得到之固體成分，以800〜1100°C進行加熱處理來形 成。又，固體反應物之形成，亦可以對在鹼水溶液中添加 鈦化合物水溶液和鋇化合物之鹼水溶液所得到之固體成分 ，以8 00〜1 lOOt進行加熱處理來形成。而且，固體反應物 200424129 之形成，亦使氧化鈦與碳酸鋇混合接觸後，以8〇〇〜;n00°C 進行加熱處理來形成。 如此的鈦酸鋇粉末之製造方法，鈦化合物及鋇化合物 可以使用各自的氧化物、鹵化物、氫氧化物、硝酸鹽、硫 酸鹽、醋酸鹽、高氯酸鹽、草酸鹽、碳酸鹽及醇鹽之至少1 種，例如鈦化合物可以使用四氯化鈦，又，鋇化合物可以 使用從氯化鋇及氫氧化鋇之至少1種。 而且，如此的鈦酸鋇粉末之製造方法，固體反應物之 鋇原子和欽原子之比爲1.001〜1.010，最好是1.003〜1.006 ，鈦酸鋇粉末之製造上反應將較容易均勻地發生，從提升 鈦酸鋇粉末的均勻性這點來說，這乃是較佳。而且，隨著 積層陶瓷電容器之高積層化、薄層化，介電體材料必須小 粒徑化，因此鈦酸鋇粉末之平均粒徑最好是〇.纟V m以下。 【實施方式】 以下，具體說明本發明之實施形態。 在本發明，鈦化合物可以使用氧化物、鹵化物、氫氧 化物、硝酸鹽、硫酸鹽、醋酸鹽、高氯酸鹽、草酸鹽、碳 酸鹽、及醇鹽之至少1種。具體上之化合物，以氧化鈦、 氫氧化鈦、.四氯化鈦、三氯化鈦、氫氧化鈦、硫酸？等爲 佳，此等當中，以氧化鈦、四氯化鈦爲更佳。 鋇化合物可以使用氧化物、鹵化物、氫氧化物、硝酸 鹽、硫酸鹽、醋酸鹽、高氯酸鹽、草酸鹽、碳酸鹽及醇鹽 之至少1種。具體上之化合物，以碳酸鋇、氯化鋇、氫氧 化鋇、硝酸鋇、硫酸鋇、醋酸鋇等爲佳，其中以碳酸鋇、 -11- 200424129 氯化鋇、氫氧化鋇等爲更佳。又，亦可以使用預先使氯化 鋇等之鹵化物、硝酸鹽、硫酸鹽、醋酸鹽等之鋇鹽化合物 與NaOH、KOH等鹼金屬氫氧化物進行接觸反應所生成之 氫氧化鋇。 關於上述使鈦化合物和鋇化合物接觸來形成固體成分 之方法，可以採用以往之液相反應法。又，使用液相反應 法進行調製時，可以使鈦化合物與鋇化合物在室溫至200°C 之液相進行反應來得到鈦酸鋇。此時所得到之鈦酸鋇係立 方晶（或是疑似立方晶）。以800〜1 100 °C對如此所得到之鈦 酸鋇固態物加熱處理可得到固體反應物，此時，結晶轉換 成爲正方晶。藉由使用如此加熱處理將結晶系轉換成爲正 方晶之鈦酸鋇作爲介電體.材料，可以得到高介電特性。又 ，使上述之鈦化合物與鋇化合物接觸，以800〜1 1 00°C加熱 處理來形成固體反應物之方法，可以採用以往的固相反應 法。將鈦化合物與鋇化合物採用固相反應法來調製時，藉 由加熱處理使鈦化合物與鋇化合物產生反應，可以生成正 方晶且結晶性尚之駄酸鋇。 接著，具體？述反應法之效果。 固相反應法，使用氧化鈦作爲原料鈦化合物，又，鋇 化合物以使用碳酸鋇、氫氧化鋇、或是氧化鋇爲佳。此處 所使用之氧化鈦，通常BET比表面積爲1〜100m2/g，爲得 到更微粒之鈦酸鋇，上述比表面積以10〜100m2/g爲佳。又 ，調配鈦化合物與鋇化合物使所得到固體反應物中鋇原子 和鈦原子之比爲1.000〜1.005。此鈦化合物與鋇化合混合接 -12- 200424129 觸得到固態物，以800〜1100 °c對其加熱處理（燒成）、使進 行反應而得到固體反應物。所得到之固體反應物依照必要 可以使用球磨機等進行粉碎來調整粒度。 另一方面，液相反應法，可以使用以往之水熱法、低 溫液相反應法、草酸法、醇鹽法等。上述鈦化合物及鋇化 合物之中，以使用水溶性化合物爲佳，使用各自至少一種 之組合，使此等溶液接觸大致上可以調製固態物。其組合 雖然可以隨意，但是以下之組合爲佳。 (1) 四氯化鈦及氯化鋇 (2) 四氯化鈦及氫氧化鋇 (3) 四氯化鈦、氯化鋇及氫氧化鋇 (4) 四氯化鈦、三氯化鈦及氯化鋇 (5) 四氯化鈦、三氯化鈦、氯化鋇及氫氧化鋇 上述中’爲了得到更微粒的鈦酸鋇粉末，以採用液相 反應法爲佳，以下列舉更佳的方法。 使鈦化合物水溶液（以下稱爲「水溶液（1)」）和鋇化合 物水溶液（以下稱爲「水溶液（II)」）接觸，大致上可以得到 固態物’此時’水溶液（I)」及溶液（11)」以鹼性狀態接觸爲 佳。具·體上，可以採用以下的方法。 (1) 使水彳谷液（I)」及溶液（π)」在鹼水溶液中接觸。 (2) 使水溶液（I)」及溶液（II)」混合，將此混合液與 鹼水溶液接觸。 (3) 使水溶液（I)」與鋇化合物之鹼水溶液接觸。 (4) 將水溶液（I)」與鋇化合物之鹼水溶液加入鹼水溶 200424129 液中進行接觸。 上述之中，考慮生產率及反應均勻性時，以使用如上 述（3)及（4)那般預先將鋇化合物調製成鹼水溶液之方法爲佳 。此時，鹼來源可以使用NaO Η、KO Η之類的鹼金屬氫氧 化物。因爲氯化鋇之類的鋇鹽特別是在酸性狀態下溶解度 低，以四氯化鈦之類的酸性鈦化合物和鋇鹽之混合水溶液 作爲出發原料液時，調製其混合水溶液是有困難的，特別 是混合水溶液中之鈦化合物及鋇鹽之濃度有其界限。具體 上，調製四氯化鈦和氯化鋇之混合水溶液時，金屬離子之 合計濃度爲1.2 mol/1程度，生產率有其界限。 此處，藉由使鋇化合物預先與鹼化合物接觸，例如使 氯化鋇等之鹵化物、硝酸鹽、硫酸鹽、醋酸鹽等鋇鹽化合 物，一時轉換爲氫氧化鋇，使其與鈦化合物之水溶液（I)接 觸而進行反應。例如，在鹼水溶液中同時使四氯化鈦水溶 液和氯化鋇水溶液接觸之方法、在鹼水溶液中添加四氯化 鈦和氯化鋇之混合水溶液來進行接觸反應之方法，所得到 固態物中易有氯成分殘留。但是，預先將鋇化合物調配成 鹼水溶液，藉由將鋇化合物預先轉換成氫氧化物，和鈦化 合物之反應可以更爲均勻地進行，可以得到氯成分較少、 更高純度之鈦酸鋇固態物。 又，使鈦化合物水溶液和鋇化合物水溶液接觸時，最 好是邊控制鈦化合物和鋇化合物之莫耳比爲〇·8〜1.2邊進行 接觸來調製固態物。藉由控制供應之鈦化合物和鋇化合物 之莫耳比，因爲製造上反應將較容易均勻地發生，從提升 -14- 200424129 鈦酸鋇粉末的均勻性這點來說’這乃是較佳。 以下，以鈦酸鋇粉末固態物之調製方法爲具體例，來 說明使用液相反應法之較佳狀態。該例鈦化合物係使用四 氯化鈦水溶液，鋇化合物係使用鋇化合物之驗水溶液。 四氯化鈦之濃度以0.1 mol/l以上爲適當，以0.3 mol/l 以上爲佳、以〇·4〜3.0mol以上爲更佳。另一方面，鋇離子 之濃度以〇.〇5 mol/l以上爲適當，以0.1〜2.0 mol/1爲佳。 使此等適當濃度之四氯化鈦水溶液（I)和鋇化合物之鹼水溶 液（II)接觸。鋇化合物之鹼水溶液之鹼來源係使用NaOΗ、 ΚΟ Η之類鹼金屬之氫氧化物，其濃度通常爲0.2〜15 mol/l， 使上述之鋇化合物轉換爲氫氧化物所需要之充分濃度，亦 即，鋇離子之濃度以上的濃度爲佳。 接著，接觸時及反應時之pH以1.3以上爲適當，13.5 以上爲佳、13.8以上爲更佳。水溶液（II)之鹼濃度，可以在 保持如此之適當範圍之氫離子濃度下進行調整。反應中爲 了保持pH在此規定値，亦可以由另外系統供應必要量之 NaOH水溶液等鹼水溶液。又，在反應容器中預先注入調整 至當量濃度之鹼水溶液，在此鹼水溶液中添加上述水溶液（I) 及水溶液（II)來進行接觸。此時之鹼水溶液最好是加熱至高 一點之溫度’使添加水溶液（I)及水溶液（II)後可以達到規定 反應溫度爲佳。如此，藉由保持反應中pH在一定値，可以 確保均勻反應，結果，鋇原子和鈦原子之比可以適當地控 制，可以調製均勻的鈦酸鋇固態物。 而且’使水溶液（I)與水溶液（II)接觸反應時，鈦化合物 -15- 200424129 和鋇化合物之莫耳比以控制在0.8〜1.2爲佳。如此，鈦化合 物和鋇化合物在反應系內之絕對濃度，從反應初期至反應 終了爲止，可以保持一定，藉此，可以進行均勻反應。又 ，使水溶液（I)和水溶液（Π)接觸反應時之溫度，以80〜100 °C爲佳、以85〜9 5 °C爲更佳。又，設定溫度以設定在此適當 溫度範圍之± 1 °C範圍內且一定爲佳。在反應容器內使水溶 液⑴與水溶液（II)接觸，例如進行數秒〜20分鐘充足時間之 攪拌，可以生成粒子狀之固態物，此固態物之主要成分爲 鈦酸鋇。生成之固態物，在反應中亦可以泥漿狀連續地抽 出，或是等反應容器一旦反應終了後再抽出亦可。將如此 生成之固態物分離，以800〜1100°C施行加熱處理（燒成）得 到固體反應物，最好是以球磨機對上述固態反應物進行粉 碎來調製粒度，藉由粉碎使成爲微粒，接著之水洗處理時 ，固體反應物在水中可以分散良好，可以進行均勻之水洗 來去除鋇成分。 水洗如此得到之固體反應物，可以得到作爲製品之鈦 酸鋇粉末，水洗所用之水，以去除溶解二氧化碳氣體、氧 氣、或是不純物成分之純水爲佳。可以採用種種的方法進 行水洗，例如，以使用附有攪拌器之容器、或是球磨機、 振動磨機等邊進行粉碎邊洗淨爲佳，以藉由數次傾濾 (decantation)、過濾來進行水洗爲更佳。如此，本發明方法 係進行水洗來去除存在於上述固體反應物表面之未反應鋇 化合物、剩餘之鋇成分等。但是，過度水洗有可能將固體 反應物內部的鋇成分過量地去除，導致最終製品之Ba/Ti -16- 200424129 在1以下’結果使形成介電體之介電特性降低。因此，本 — 胃B月之方法’進行水洗至固體反應物中之鋇成分爲 ‘ 1 〜lOOOOppm、以 1〇 〜5〇〇〇ppm 爲佳、以 100 〜3 000ppm 爲特 佳。又’ Ba/Ti在ι·010附近屬於Ba成分較多之固體反應 物時’可以洗淨去除鋇成分來使Ba/Ti在i.ooi附近。Ba/Ti 比較低之固體反應物時，藉由洗淨去除鋇成分時應注意 Ba/Ti不要在〗以下。如此所得到之鈦酸鋇粉末，可以依照 必要加以乾燥。藉由如此去除粒子表面之鋇成分來形成介 電體磁器組成物時，可與其他金屬成分均勻混合分散，結 0 果介電特性得到改良。 水洗時之溫度爲20〜80°C，以30〜70eC爲佳、以40〜60 °C之溫度範圍爲更佳。藉由使水洗溫度爲40〜60 °C，可以更 有效率地去除未反應之鋇化合物成分、過剩的鋇成分等。 又，水洗時之pH在1 0以下，可以增加水中之鈦酸鋇 粉末之沈澱速度、提升洗淨效率。而且，水洗時之氧化鈦 濃度爲40wt%以下，以10〜30 wt%爲佳、以10〜20 wt%爲更 佳。如此藉由特定之氧化鈦濃度範圍，可以保持洗淨時之pH φ 在1 〇以下，可以更有效率地洗淨。 本發明以二氧化碳處理如上述那般所得到之鈦酸鋇粉 末，乃是較佳狀態。二氧化碳處理的方法，可以舉出的有（1) 以8 0 0〜1 1 0 0 °c加熱處理使鈦化合物和鋇化合物接觸所得到 之固態物所形成的固體反應物’其後對前述固體反應物進 行水洗，接著在固體反應物之水懸浮液中’投入規定量之 二氧化碳氣體或是二氧化碳水溶液’使二氧化碳與固體反 -17- 200424129 應物接觸之處理方法，或是（2)以800〜1100°C加熱處理使 鈦化合物與鋇化合物接觸所得固態物來形成固體反應物， 接著水洗前述固體反應物，接著進行水洗，按照必要進行 粉碎，接著使二氧化碳與乾燥固體反應物接觸之處理方法 等。藉由如此的二氧化碳處理，可以使所得到鈦酸鋇粉末 安定化，爲了使用鈦酸鋇粉末作爲陶瓷電容器之介電材料 ，而使其在水中分散或是在製膏時保持鋇原子和鈦原子比 不變，結果可以得到特性優良之積層陶瓷電容器。200424129 IX. Description of the invention: [Technical field to which the invention belongs] The present invention relates to a method for manufacturing a barium titanate powder, and more particularly to a method for manufacturing a barium titanate powder suitable for a dielectric material. · The dielectric material has a highly crystalline perovskite structure with a particle size of 1 // m or less. [Prior Art] Because the dielectric material used in multilayer ceramic capacitors requires good temperature characteristics at high dielectric constants, low bias dependence, and excellent withstand voltage, barium titanate-based compositions have been widely used in the past. Thing. Generally, a multilayer ceramic capacitor can be manufactured as follows. That is, a dielectric powder such as barium titanate is mixed with an organic adhesive, suspended, and formed into a sheet shape using a doctor blade to form a green sheet. Next, metal powder for the internal electrode is mixed with organic compounds such as organic solvents, plasticizers, and organic adhesives to form a metal powder paste, which is printed on the printed circuit board by a screen printing method. Next, these are dried and laminated in a staggered manner, and heat-treated at about 300 ° C in the atmosphere to remove organic components, and then sintered at a temperature of at least ° C. Finally, external electrodes were plated on both ends of the dielectric ceramic layer to obtain a laminated ceramic capacitor. This sintering temperature is generally about 100 ° C for lead systems. The composition of the barium titanate-based dielectric magnets must be about 1,300 ° C, or more, because of the different sintering characteristics. Higher temperatures. In this way, the multilayer ceramic capacitor is manufactured, and the dielectric layer and the inner metal layer are sintered at the same time. 200424129 In this way, the metals used to form the internal electrode metal layer of multilayer ceramic capacitors have traditionally used precious metal powders such as silver, palladium, platinum, and gold, or base metal powders such as nickel, cobalt, iron, molybdenum, and tungsten, because Recently, cheaper electronic materials have been required, and the development of multilayer ceramic capacitors using the above-mentioned base metal powder is being actively carried out. In the above-mentioned manufacturing steps of the multilayer ceramic capacitor, when noble metal powder is used as the internal electrode, sintering can also be performed in an oxygen environment. However, if a base metal powder such as nickel is used as the internal electrode, there is a risk that the insulation will increase due to oxides in an oxidizing environment in a high-temperature atmosphere. Therefore, this situation must be performed in a reducing environment such as hydrogen. sintering. As mentioned above, in the manufacturing steps of multilayer ceramic capacitors, organic components are removed by heat treatment in the atmosphere. In addition, the redox generated when the nickel electrode is sintered in a reducing environment, the metal powder will expand and contract. A volume change occurs. On the other hand, the dielectric body itself has a volume change due to sintering, but because the dielectric body and metal powder belonging to different substances are sintered at the same time, the volume changes (expansion, contraction) of the respective substances during the sintering process are sintered. different. Therefore, the metal paste layer is deformed, and as a result, there is a problem of a structural defect such as cracking or peeling, and the interlayer structure is damaged. Therefore, it is required that the dielectric material can be sintered at a low temperature as much as possible. In addition, since the dielectric material is an oxide ', a material that can maintain a state of equilibrium with oxygen in the atmosphere has been used in the past. However, when manufacturing the nickel-electrode multilayer ceramic capacitor as described above, the sintering is performed under the condition of cyclic nature. Therefore, the dielectric material used at this time is reduced under the condition of a low oxygen partial pressure. It must be used in 200424129 without semiconductorization. Only those with resistance to reduction can be used. Therefore, in the past, in view of this necessity, many non-reducing dielectric magnetic magnet compositions have been reviewed. For example, the rare earth atoms such as yttrium and the oxides of magnesium, manganese, and silicon have been blended with barium titanate as the main component. The fired material is used as the dielectric body of the multilayer ceramic capacitor. The conventional technology of such multilayer ceramic capacitors not only improves the reduction resistance and low-temperature sintering properties of the dielectric material, but also satisfies X7R characteristics and bias characteristics under high temperature load characteristics. However, in recent years, "with the significant miniaturization of mobile phones or personal computers and the demand for large capacitance quantification", multilayer ceramic capacitors have also been required to be thinner. At present, the thickness is required to be thinner and thinner. However, when the dielectric layer is thinned, there is a problem that the dielectric breakdown voltage between the internal electrodes decreases. Furthermore, from the viewpoint of energy saving, it is required to be able to save power. Therefore, it is desired to develop a dielectric material that has less dielectric loss and less heat generation at room temperature or higher. In addition, multilayer ceramic capacitors are rapidly moving toward miniaturization and large capacitance in addition to thin layers. At this time, it is necessary to have good withstand voltage characteristics, small particle size of the dielectric material itself, and uniform layer density, and it must be able to ensure sufficient Capacitor capacity. In this way, "to meet the required characteristics in recent years, various development technology proposals have been made", and in particular, various production methods are known regarding a method for producing barium titanate powder as the raw material. The method for producing barium titanate powder can be roughly classified into a solid phase reaction method in which a titanium compound and a barium compound are mixed and fired, and a liquid phase 200424129 reaction method in which a water-soluble titanium compound and a water-soluble barium compound are reacted in a liquid phase. The above-mentioned solid phase reaction method, because the compound is reacted at a high temperature, the obtained barium titanate powder has a large particle size, a wide particle size distribution, and its shape is not constant, so it has the problem of poor dispersibility during slurrying. presence. In order to solve this problem, a method for producing a barium titanate powder has been disclosed (for example, refer to Japanese Patent Application Laid-Open No. 1 -3 3 8 5 24 (Patent Document 1)), which is characterized by having a selective specific surface area of 1 A selection step of BaC03 powder below 0 m2 / g and a Ti02 powder having a specific surface area of 15 m2 / g or more, a mixing step of mixing these BaC03 powder and Ti02 powder, and a firing step of firing these mixtures. In addition, the liquid phase reaction method has disclosed that at least one of hydrated titanium oxide, barium chloride, and nitrate, 1 mol of barium chloride and / or nitrate, and 2.1 to 5 mol of alkali metal hydroxide at 60 M 10 A manufacturing method of reacting at a temperature of 120 ° C to 10,000 times mol of titanium at ° C (for example, refer to Japanese Patent Publication No. 5-73 6 95 (Patent Document 2). Manufacturing method for reacting hydrated titanium oxide, barium hydroxide, and alkali metal hydroxide at 60 to 110 ° C in the presence of water with a conversion of titanium to 120 to 10,000 times mol (for example, refer to Japanese Patent Japanese Patent Publication No. 5-73 696 (Patent Document 3)) also discloses a manufacturing method of reacting a hydrolyzed product of a titanium compound and a water-soluble barium salt in a strong alkaline aqueous solution (for example, refer to Japanese Patent Patent No. 3 -3 90 1 4 (Patent Document 4)). There is also disclosed a method in which titanium chloride is hydrolyzed in an aqueous solution, the aqueous solution is temporarily restored to alkalinity to remove chloride ions, and then a barium-soluble salt is added. One of them 'make in strong base A method for producing a reaction in an aqueous solution (for example, refer to Japanese Patent Publication No. 6-649 (Patent Document 5)), and 200424129 also discloses a mixed solution in which a titanium compound such as titanium tetrachloride and a barium salt coexist. A method of obtaining an approximately spherical crystalline perovskite structure by contacting an alkaline aqueous solution heated to 70 to 100 ° C (for example, refer to Japanese Patent Laid-Open No. 7-2 3 2923 (Patent) Document 6)). There is also disclosed a method for producing barium titanate powder, which is characterized by controlling the m ο 1 ratio of the titanium compound / barium compound to 0 · 8 ~ 1 · 2 while using stirring An aqueous solution of a titanium compound and an alkaline aqueous solution of a barium compound are contacted (for example, refer to Japanese Patent International Publication No. W099 / 599 1 (Patent Document 7). In addition, there is also disclosed a calcined titanium obtained by a calcination liquid phase reaction method After the ore-type compound powder is washed with an acid solution (for example, refer to Japanese Patent Laid-Open No. 2 9 9 8 21 (Patent Document 8)). However, each of the above-mentioned Japanese Patent Laid-open Documents 1 to 7 Technology, off Although the voltage withstand characteristics, the non-agglomeration characteristics of particles after firing, the uniform characteristics of the layer density, and the characteristics that fully ensure the capacity of the capacitor have been improved to some extent in the past, they have been improved to some extent when forming dielectrics. In terms of dielectric characteristics such as dielectric loss and temperature characteristics, they are still not satisfactory enough to meet the miniaturization of the dielectric layer of the multilayer ceramic capacitor in recent years due to the thinning of the thin film and the quantification of the large capacitance. In the technique described in 8, in order to wash the calcined perovskite-type compound powder and the case of barium titanate, the barium component will be excessive and dissolve, and it is not easy to control the accuracy at a ratio of barium atom to titanium atom of 1000 minutes. 1 to 1/1000. The present invention is directed to the problems attached to the barium titanate powder described in the aforementioned Japanese Patent Documents 1 to 8, that is, the object of the present invention is to provide a simpler manufacturing method of the barium titanate powder-9-200424129. The powder has excellent dielectric loss and temperature characteristics when forming a dielectric body. [Summary of the Invention] The present inventors and others have reviewed a manufacturing method that can achieve the above-mentioned purpose by drilling drill collars. As a result, they found that the barium titanate powder obtained by the solid-phase reaction method and the liquid-phase reaction method was heated and then washed with water. A barium titanate powder having excellent dielectric characteristics when a dielectric is formed can be obtained, and the present invention has finally been completed. The method for producing a barium titanate powder according to the present invention is characterized in that the solid component obtained by contacting a titanium compound and a barium compound is heat-treated at 800 to 1 100 ° C to form a solid reactant, Thereafter, the solid reaction product was washed with water. According to the present invention, the barium titanate powder obtained by the solid-phase reaction method or the liquid-phase reaction method is heated and then washed with water to obtain a barium titanate powder having excellent dielectric characteristics when a dielectric is formed. In the method for producing barium titanate of the present invention, the above-mentioned water washing is preferably performed at a temperature of 2 ° C to 80 ° C, preferably 30 ° C to 70 ° C, and more preferably in a range of 40 ° C to 60 ° C. It is effective to improve the cleaning efficiency. With such a method for producing barium titanate powder and the formation of a solid reactant, the solid content obtained by contacting a titanium compound compound aqueous solution and a barium compound in the presence of a base can be It is formed by heat treatment at 800 ~ 1100 ° C. For the formation of solid reactants, the solid content obtained by adding an aqueous solution of a titanium compound and an aqueous solution of a barium compound to an alkaline aqueous solution can be heated at 800 ~ 1 lOOt It is formed by treatment. In addition, the formation of solid reactant 200424129 is also formed by mixing and contacting titanium oxide with barium carbonate and heating treatment at 800 ° C to n00 ° C. The production method of such a barium titanate powder, titanium Compounds and barium compounds can use at least one of the respective oxides, halides, hydroxides, nitrates, sulfates, acetates, perchlorates, oxalates, carbonates, and alkoxides, such as titanium compounds. As the material, titanium tetrachloride can be used, and as the barium compound, at least one of barium chloride and barium hydroxide can be used. In addition, in the method for producing such a barium titanate powder, the ratio of the barium atom to the thion atom of the solid reactant It is 1.001 ~ 1.010, preferably 1.003 ~ 1.006. The reaction in the production of barium titanate powder will easily occur uniformly, which is better from the viewpoint of improving the uniformity of barium titanate powder. The high-layering and thin-layering of laminated ceramic capacitors requires a small particle diameter of the dielectric material, so the average particle diameter of the barium titanate powder is preferably 0. 纟 V m or less. Embodiments of the present invention. In the present invention, titanium compounds can use at least oxides, halides, hydroxides, nitrates, sulfates, acetates, perchlorates, oxalates, carbonates, and alkoxides. 1. The specific compounds are preferably titanium oxide, titanium hydroxide, titanium tetrachloride, titanium trichloride, titanium hydroxide, sulfuric acid? Etc. Among them, titanium oxide and titanium tetrachloride are used as examples. Even better. Barium compounds can be used Compounds, halides, hydroxides, nitrates, sulfates, acetates, perchlorates, oxalates, carbonates, and alkoxides. Specific compounds include barium carbonate, barium chloride, Barium hydroxide, barium nitrate, barium sulfate, barium acetate, etc. are preferred, and barium carbonate, -11-200424129 barium chloride, barium hydroxide, etc. are more preferred. Alternatively, a halogenated barium chloride or the like may be used in advance Barium hydroxide produced by contacting barium salt compounds such as metals, nitrates, sulfates, acetates, etc. with alkali metal hydroxides such as NaOH, KOH, etc. Regarding the above-mentioned method of contacting a titanium compound and a barium compound to form a solid component The conventional liquid phase reaction method can be used. When the liquid phase reaction method is used for preparation, the titanium compound and the barium compound can be reacted at a liquid phase from room temperature to 200 ° C to obtain barium titanate. The barium titanate-based cubic crystals obtained at this time (or suspected cubic crystals). The solid barium titanate solid thus obtained was heated at 800 to 1 100 ° C to obtain a solid reactant. At this time, the crystal was converted into a tetragonal crystal. By using such a heat treatment to convert the crystal system to tetragonal barium titanate as a dielectric material, high dielectric properties can be obtained. In addition, as a method of contacting the above-mentioned titanium compound with a barium compound and heat-treating at 800 to 110 ° C to form a solid reactant, a conventional solid-phase reaction method can be adopted. When the titanium compound and the barium compound are prepared by a solid-phase reaction method, the titanium compound and the barium compound are reacted by heat treatment to produce barium osmate, which is tetragonal and has high crystallinity. Then, specific? The effect of the reaction method is described. In the solid-phase reaction method, titanium oxide is used as a raw material titanium compound, and barium compound is preferably barium carbonate, barium hydroxide, or barium oxide. The titanium oxide used here usually has a BET specific surface area of 1 to 100 m2 / g. In order to obtain finer barium titanate, the specific surface area is preferably 10 to 100 m2 / g. The titanium compound and the barium compound were blended so that the ratio of barium atoms to titanium atoms in the obtained solid reaction product was 1.000 to 1.005. This titanium compound is mixed with barium compound to contact -12- 200424129 to obtain a solid material, which is heated (fired) at 800 ~ 1100 ° c and reacted to obtain a solid reactant. The obtained solid reactant may be pulverized using a ball mill or the like as necessary to adjust the particle size. On the other hand, as the liquid phase reaction method, a conventional hydrothermal method, a low temperature liquid phase reaction method, an oxalic acid method, an alkoxide method, and the like can be used. Among the above-mentioned titanium compounds and barium compounds, water-soluble compounds are preferably used, and a combination of at least one of them is used, and contacting these solutions can substantially prepare a solid. Although the combination is optional, the following combinations are preferred. (1) titanium tetrachloride and barium chloride (2) titanium tetrachloride and barium hydroxide (3) titanium tetrachloride, barium chloride and barium hydroxide (4) titanium tetrachloride, titanium trichloride and Barium chloride (5) Titanium tetrachloride, titanium trichloride, barium chloride, and barium hydroxide Among the above, in order to obtain finer particles of barium titanate powder, the liquid phase reaction method is preferred, and the following are more preferred method. The titanium compound aqueous solution (hereinafter referred to as "aqueous solution (1)") and the barium compound aqueous solution (hereinafter referred to as "aqueous solution (II)") are brought into contact with each other to obtain a solid 'current' aqueous solution (I) 'and a solution ( 11) It is better to contact in alkaline state. For the body, the following methods can be used. (1) The leech grain liquid (I) "and the solution (π)" are brought into contact with an alkaline aqueous solution. (2) The aqueous solution (I) '' and the solution (II) '' are mixed, and this mixed solution is brought into contact with an alkaline aqueous solution. (3) The aqueous solution (I) '' is brought into contact with an alkaline aqueous solution of a barium compound. (4) Add the aqueous solution (I) "and the alkaline aqueous solution of the barium compound to the alkaline aqueous solution 200424129 to make contact. Among the above, when productivity and reaction uniformity are considered, it is preferable to use a method of preparing a barium compound into an alkaline aqueous solution in advance as described in (3) and (4) above. In this case, an alkali metal hydroxide such as NaOΗ, KOO can be used as the alkali source. Because a barium salt such as barium chloride has a low solubility especially in an acidic state, when a mixed aqueous solution of an acidic titanium compound such as titanium tetrachloride and a barium salt is used as a starting material liquid, it is difficult to prepare the mixed aqueous solution. In particular, the concentrations of titanium compounds and barium salts in mixed aqueous solutions have their limits. Specifically, when a mixed aqueous solution of titanium tetrachloride and barium chloride is prepared, the total concentration of metal ions is about 1.2 mol / 1, and productivity has its limits. Here, by contacting a barium compound with an alkali compound in advance, for example, a barium salt compound such as a barium chloride, a nitrate, a sulfate, or an acetate is temporarily converted into barium hydroxide to make it contact with a titanium compound. The aqueous solution (I) is contacted to perform a reaction. For example, a method in which a titanium tetrachloride aqueous solution and a barium chloride aqueous solution are simultaneously contacted in an alkaline aqueous solution, and a method in which a mixed aqueous solution of titanium tetrachloride and barium chloride is added to the alkaline aqueous solution to perform a contact reaction. Prone to residual chlorine. However, the barium compound is prepared into an alkaline aqueous solution in advance, and by converting the barium compound into a hydroxide in advance, the reaction with the titanium compound can be performed more uniformly, and a barium titanate solid with less chlorine content and higher purity can be obtained. Thing. When the titanium compound aqueous solution and the barium compound aqueous solution are brought into contact with each other, it is desirable to prepare the solid matter by contacting the titanium compound and the barium compound while controlling the molar ratio of the titanium compound and the barium compound to 0.8 to 1.2. By controlling the molar ratio of the titanium compound and barium compound supplied, since the manufacturing reaction will occur more easily and uniformly, it is better from the point of improving the uniformity of -14-200424129 barium titanate powder. In the following, a method for preparing a solid substance of barium titanate powder as a specific example is used to describe a preferred state using a liquid phase reaction method. In this example, a titanium tetrachloride aqueous solution was used as the titanium compound, and a barium compound was used as the test solution for the barium compound. The concentration of titanium tetrachloride is preferably 0.1 mol / l or more, more preferably 0.3 mol / l or more, and more preferably 0.4 to 3.0 mol or more. On the other hand, the concentration of barium ions is preferably 0.05 mol / l or more, and more preferably 0.1 to 2.0 mol / 1. The titanium tetrachloride aqueous solution (I) of these appropriate concentrations is brought into contact with the alkaline aqueous solution (II) of the barium compound. The alkali source of the alkali aqueous solution of the barium compound is an alkali metal hydroxide such as NaOΗ, ΚΟ Η, etc., whose concentration is usually 0.2 to 15 mol / l. The sufficient concentration required to convert the above barium compound into a hydroxide, That is, a concentration equal to or higher than the concentration of barium ions is preferred. Next, the pH during contact and reaction is preferably 1.3 or more, more preferably 13.5 or more, and even more preferably 13.8 or more. The alkali concentration of the aqueous solution (II) can be adjusted while maintaining the hydrogen ion concentration in such an appropriate range. In order to maintain the pH during the reaction, an alkaline aqueous solution such as a NaOH aqueous solution may be supplied from another system. In addition, an alkali aqueous solution adjusted to an equivalent concentration was injected into the reaction vessel in advance, and the aqueous solution (I) and the aqueous solution (II) were added to the alkali aqueous solution to make contact. The alkaline aqueous solution at this time is preferably heated to a higher temperature 'so that the predetermined reaction temperature can be reached after the aqueous solution (I) and the aqueous solution (II) are added. In this way, by keeping the pH constant during the reaction, a uniform reaction can be ensured. As a result, the ratio of the barium atom to the titanium atom can be appropriately controlled, and a uniform solid barium titanate can be prepared. When the aqueous solution (I) and the aqueous solution (II) are brought into contact and reacted, the molar ratio of the titanium compound -15-200424129 and the barium compound is preferably controlled to 0.8 to 1.2. In this way, the absolute concentration of the titanium compound and the barium compound in the reaction system can be kept constant from the beginning of the reaction to the end of the reaction, thereby enabling a uniform reaction. The temperature at which the aqueous solution (I) and the aqueous solution (Π) are brought into contact with each other is preferably 80 to 100 ° C, and more preferably 85 to 95 ° C. In addition, it is preferable to set the temperature within ± 1 ° C of the appropriate temperature range. Contacting the aqueous solution 水 with the aqueous solution (II) in the reaction container, for example, by stirring for a sufficient time of several seconds to 20 minutes, can produce a particulate solid, the main component of which is barium titanate. The generated solids can also be continuously extracted in the form of a slurry during the reaction, or they can be extracted after the reaction vessel is finished. The solid matter thus generated is separated and subjected to heat treatment (firing) at 800 to 1100 ° C to obtain a solid reactant. The solid reactant is preferably pulverized by a ball mill to adjust the particle size, and the particles are pulverized by pulverization. During the water washing treatment, the solid reactant can be dispersed well in water, and the barium component can be removed by uniform water washing. The solid reactant thus obtained can be washed with water to obtain barium titanate powder as a product. The water used for washing is preferably pure water that removes dissolved carbon dioxide gas, oxygen gas, or impurities. Various methods can be used for water washing. For example, it is better to use a container with a stirrer, or a ball mill, a vibration mill, and the like to perform washing while crushing, and to perform decantation and filtration several times. Washing is better. Thus, the method of the present invention is performed by washing with water to remove unreacted barium compounds, remaining barium components, and the like existing on the surface of the solid reactant. However, excessive water washing may excessively remove the barium component inside the solid reactant, resulting in Ba / Ti -16-200424129 of 1 or less in the final product. As a result, the dielectric characteristics of the formed dielectric are reduced. Therefore, according to the method of "Stomach B Month", the barium component in the solid reaction product is washed with water to ‘1 to 1000 ppm, preferably to 10 to 5000 ppm, and particularly preferably to 100 to 3,000 ppm. When "Ba / Ti is a solid reactant with a large Ba content near ι · 010", the barium component can be washed and removed to make Ba / Ti near i.ooi. For solid reactants with relatively low Ba / Ti, care should be taken when removing the barium component by washing. The barium titanate powder thus obtained can be dried as necessary. When the barium component on the surface of the particles is removed to form a dielectric magnet composition, it can be uniformly mixed and dispersed with other metal components, resulting in improved dielectric characteristics. The temperature during washing is 20 ~ 80 ° C, preferably 30 ~ 70eC, and more preferably 40 ~ 60 ° C. By setting the water washing temperature to 40 to 60 ° C, unreacted barium compound components, excess barium components, and the like can be removed more efficiently. In addition, the pH during water washing is below 10, which can increase the precipitation speed of barium titanate powder in water and improve the washing efficiency. The titanium oxide concentration during water washing is 40% by weight or less, preferably 10 to 30% by weight, and more preferably 10 to 20% by weight. In this way, with a specific titanium oxide concentration range, the pH φ at the time of washing can be kept below 10, and washing can be performed more efficiently. It is preferred that the barium titanate powder obtained as described above be treated with carbon dioxide in the present invention. Methods of carbon dioxide treatment include (1) a solid reactant formed by a solid obtained by contacting a titanium compound and a barium compound by heating at 800 to 110 ° C, and then to the aforementioned solid The reactants are washed with water, and then the method of "injecting a specified amount of carbon dioxide gas or carbon dioxide aqueous solution" into the aqueous suspension of the solid reactant to contact carbon dioxide with the solid anti-17-200424129 reactant, or (2) 800 ~ 1100 ° C Heat treatment process to make titanium compound and barium compound contact solid matter to form solid reactant, then wash the solid reactant with water, then wash with water, pulverize as necessary, and then contact carbon dioxide with dry solid reactant Wait. With such carbon dioxide treatment, the obtained barium titanate powder can be stabilized. In order to use the barium titanate powder as a dielectric material for ceramic capacitors, it can be dispersed in water or can maintain barium atoms and titanium atoms during paste production. As a result, the multilayer ceramic capacitor having excellent characteristics can be obtained.
如此所製得之鈦酸鋇粉末，粒徑爲1.0 // m以下，粒徑 以0.05〜0.5 //m爲佳、以0.05〜0.3 //m爲更佳。又，因爲如 此之鈦酸鋇粉末之粒度分布狹窄與上述粒徑相輔相乘，亦 具有良好的結晶性。又，鋇原子和鈦原子比可以在 0.990〜1.010，以 1.003〜1·005 爲更佳。The particle size of the barium titanate powder thus prepared is 1.0 // m or less, and the particle size is preferably 0.05 to 0.5 // m, and more preferably 0.05 to 0.3 // m. In addition, the narrow particle size distribution of the barium titanate powder thus complemented and multiplied the above particle size, and also had good crystallinity. The ratio of barium atom to titanium atom may be 0.990 to 1.010, and more preferably 1.003 to 1.005.
如上述，本發明之方法所得到鈦酸鋇粉末，使用於介 電材料時，比介電常數高且介電損失少，而且具有良好的 溫度特性。因此，該鈦酸鋇粉末適合作爲疊層陶瓷電容器 用介電材料。 (實施例） 以下，以實施例具體地說明本發明。 (實施例1) 在具備有攪拌裝置之2升SUS製反應容器，注入0.92 規定之NaOH水溶液，保持在90°C。接著，對反應容器以 TiCl4 水溶液：77cc/分、BaCl2/NaOH 水溶液：154cc/分之 流量，連續供給加熱保持於40°C之TiCl4水溶液（TiCl4濃度 -18- 200424129 :0.472 mol/l)、和保持於 95°C 之 BaCl2/NaOH 水溶液（BaCl2 濃度：0·278 mol/1、NaOH 濃度：2·73 mol/1)，邊攪拌邊保 持在9(TC。供給之BaCl2/ TiCl4莫耳比爲1.180。 接著，將含有生成鈦酸鋇之泥漿移送熟成槽，在攪拌 下9 0 °C保持6 0分鐘。其後，施加傾濾將上部澄淸液從沈搬 物去除’且進行遠心分離來回收鈦酸鋇粉末。接著，在常 溫用水洗淨所回收的鈦酸鋇粉末，其後，在真空環境下以2 0 0 °C加熱進行乾燥，得到鋇原子和鈦原子比爲1 ·〇〇5之未燒成 鈦酸鋇粉末。 以1 000°C對上述未燒成鈦酸鋇粉末進行1.5小時加熱 處理後，使用球磨機在加熱處理後之鈦酸鋇粉末300g中添 加純水700 ml，粉碎30分鐘後，在常溫重複施行傾濾後去 除上部澄淸液，將回收之·固態物以噴霧乾燥機進行乾燥。 (實施例2)As described above, when the barium titanate powder obtained by the method of the present invention is used for a dielectric material, it has a higher specific permittivity and less dielectric loss, and has good temperature characteristics. Therefore, this barium titanate powder is suitable as a dielectric material for a multilayer ceramic capacitor. (Examples) Hereinafter, the present invention will be specifically described with reference to examples. (Example 1) A 2 liter SUS reaction vessel equipped with a stirring device was filled with a NaOH aqueous solution specified in 0.92 and maintained at 90 ° C. Next, a TiCl4 aqueous solution: 77cc / min, BaCl2 / NaOH aqueous solution: 154cc / min was continuously supplied to the reaction vessel, and a TiCl4 aqueous solution (TiCl4 concentration-18-200424129: 0.472 mol / l) heated and maintained at 40 ° C was continuously supplied, and BaCl2 / NaOH aqueous solution (BaCl2 concentration: 0 · 278 mol / 1, NaOH concentration: 2.73 mol / 1) kept at 95 ° C, and kept at 9 (TC. BaCl2 / TiCl4 molar ratio supplied while stirring) 1.180. Next, transfer the slurry containing barium titanate to the maturation tank, and keep it at 90 ° C for 60 minutes under stirring. After that, apply the decantation to remove the upper clear solution from the sediment and perform telecentric separation. The barium titanate powder was recovered. Then, the recovered barium titanate powder was washed with water at normal temperature, and then heated and dried at 200 ° C in a vacuum environment to obtain a barium atom and titanium atom ratio of 1.00. 5 unfired barium titanate powder. After heating the above unfired barium titanate powder at 1,000 ° C for 1.5 hours, 700 ml of pure water was added to 300 g of barium titanate powder after heat treatment using a ball mill. After pulverizing for 30 minutes, the upper part was removed after repeated decantation at room temperature. Qing liquid, · recovering the solid was dried to a spray dryer. (Example 2)
和實施例1同樣地對未燒成鈦酸鋇以l〇〇〇°C加熱處理 1 . 5小時後，使用球磨機粉碎後，實施例1,以常溫進行之傾 濾在實施例2則以60°C實施來去除上部澄淸液，將回收固 態物以噴霧乾燥機進行乾燥。 (比較例1) 除了使用珠磨機對加熱處理後之鈦酸鋇粉末進行粉碎 後未施加傾濾、直接使用噴霧乾燥機進行乾燥之外，使用 實施例1同樣的方法得到鈦酸鋇。 (比較例2) 在具備有攪拌裝置之2升SUS製反應容器，注入0.92 -19- 200424129 當量濃度之NaOH水溶液，保持在90°C。另一方面，混合 保持於40°C之TiCl4水溶液和預先去除未溶解成分之BaCl2 水溶液，調整TiCl4 /BaCl2之混合水溶液之BaCl2/ TiCl4 莫耳比爲1.180。接著，使用泵對反應容器以77CC/min連 續供給該混合水溶液。此時反應容器內的混合水溶液之溫 度約爲9 0 °C之一定値。接著，將生產之含有鈦酸鋇之泥漿 ’和實施例同樣地進行熟成、洗淨、乾燥，得到未燒成鈦 酸鎖粉末。 Λ. 以1 0 0 0 °C對上述未燒成鈦酸鋇粉末進行1 . 5小時加熱 處理後，使用球磨機在加熱處理後之鈦酸鋇粉末3 00g中添 加純水700 ml保持在60°C，添加10質量％醋酸水溶液調整 pH爲約8.0，保持約1小時。其後，將回收之固態物以噴 霧乾燥機進行乾燥。The unfired barium titanate was heat-treated at 1000 ° C for 1.5 hours in the same manner as in Example 1. After being pulverized with a ball mill, Example 1 was subjected to decantation at room temperature. The solution was removed at a temperature of ° C, and the recovered solid was dried by a spray dryer. (Comparative Example 1) Barium titanate was obtained in the same manner as in Example 1 except that the barium titanate powder after the heat treatment was pulverized using a bead mill without decantation, and was directly dried using a spray dryer. (Comparative Example 2) In a 2 liter SUS reaction vessel equipped with a stirring device, a 0.92 -19-200424129 equivalent concentration NaOH aqueous solution was poured and kept at 90 ° C. On the other hand, the TiCl4 aqueous solution maintained at 40 ° C and the BaCl2 aqueous solution from which undissolved components were removed beforehand were adjusted to adjust the BaCl2 / TiCl4 molar ratio of the TiCl4 / BaCl2 mixed aqueous solution to 1.180. Next, the reaction container was continuously supplied with the mixed aqueous solution at 77 CC / min using a pump. At this time, the temperature of the mixed aqueous solution in the reaction container was about 90 ° C. Next, the produced slurry containing barium titanate was matured, washed, and dried in the same manner as in the example to obtain an unfired titanate-locked powder. Λ. After heating the above unfired barium titanate powder at 1000 ° C for 1.5 hours, add 700 ml of pure water to 300 g of barium titanate powder after heat treatment using a ball mill and keep it at 60 ° C. A 10% by mass aqueous acetic acid solution was added to adjust the pH to about 8.0 and maintained for about 1 hour. Thereafter, the recovered solid matter was dried with a spray dryer.
如此所得到的上述實施例及比較例有關之鈦酸鋇粉末 ，測定此等之平均粒徑、鋇原子和鈦原子之比、及介電特 性。具體上，使用BET法求取鈦酸鋇粉末之平均粒徑。又 ，使用螢光X線分析求取鋇原子和鈦原子之比（Ba/Ti比）。 而且使用電子顯微鏡照片來測定求取平均粒徑。 又，關於實施例1、2，求取以球磨機粉碎處理後重複 傾濾次數、亦即洗淨次數和此時之Ba/Ti原子比。 另一方面，如以下實施介電特性之評價。 相對於鈦酸鋇粉末1〇〇 mol，稱量氧化鎂2 mol、氧化 鏑 2 mol、碳酸鋇5 mol、碳酸鈣4 mol、氧化矽 3 mol、 碳酸猛〇·4 mol、氧化訊0.05 mol、及氧化鉬0·1 mol，藉 -20- 200424129 由使用鉻球之球磨機對此等粉末進行1 6小時之濕式混合粉 碎得到混合粉碎品，對其進行成形，在還原環境下以1 300 °C、2小時燒成、製成厚度1 . 1 4mm之成型體。其後測定關 於燒成後成形體之比介電常數、介電損失（tan δ)及溫度特 性（TCC)。 (1) 使用LCR計量器（1 KHz、IV)測定比介電常數、介 電損失（tan δ)。 (2) 關於電容量之溫度特性（TCC)，使用LCR計量器 以測量電壓1 V測量-5 5 °C〜1 2 5 °C之電容量，調查是否滿足電 容量變化率在士 I5%(基準溫度25。〇以內（X7R特性）。上述 之各評價事項，亦即平均粒徑、鋇原子和鈦原子比、以及 介電特性之結果如表1、表2、及第1圖及第2圖所示。又 ’表1之實施例1友實施例2之原子比係傾濾次數爲3次 時之値。 表1 平均粒 徑（// m) Ba/Ti原子比 實 施 例 1 0, .2 7 1.003 實 施 例 2 0.27 1.002 比 較 例 1 0, .29 1.005 比 較 例 2 0 .30 0.990 禮 -21- 200424129 表2 實施例1 比較例1 比較例2 溫度 (°C) 比介電 常數 介電損 失(％) TCC(°/〇) (25°C基準） 比介電 常數 介電損 失(％) TCC(%) (25°C基準） 比介電 常數 介電損 失(％) TCC(°/〇) (25t基準） -55 2737 0.95 -12.6 2609 0.89 -10.2 2700 0.90 -11.5 -30 2859 0.88 -8.7 2728 0.83 -6.1 2755 0.85 -7.0 25 3132 0.66 0.0 2905 0.57 0.0 3001 0.60 0.0 45 3084 0.58 -1.5 2879 0.53 -0.9 3011 0.55 -1.2 55 3040 0.56 -2.9 2842 0.52 -2.2 2855 0.53 -2.6 56 3003 0.56 -4.1 2809 0.52 -3.3 2862 0.53 -3.8 85 2944 0.54 -6.0 2743 0.50 -5.6 2802 0.52 -5.7 105 3001 0.52 -4.2 2769 0.49 -4.7 2812 0.50 -4.5 125 3186 0.52 1.7 2844 0.49 -2.1 2920 0.50 -2.3 135 2813 0.53 -10.2 2526 0.50 -13.0 2595 0.52 -14.5 依照表1，實施例之鈦酸鋇粉末之Ba/Ti原子比較爲接 近1.0 0 0，可以得知已去除過量之鋇成分。進行酸洗淨之比 較例2之鈦酸鋇粉末之Ba/Ti原子比爲1.000以下，可以得 知鋇成分過量流出。從表1及第2圖，可以得知因爲在高 溫進行水洗（傾濾），更有效率地去除過量的鋇成分。又， 藉由表2及第1圖，可以得知實施1之鈦酸鋇粉末，和比 較例之鈦酸鋇粉末比較時，具有優良的比介電常數。 【圖式簡單說明】 (一）圖式部分 第1圖爲顯示實施例及比較例之介電常數和溫@ _ 係圖。 -22- 200424129 第2圖爲顯示施行常溫洗淨和溫水（6(TC)洗淨之Ba/Ti 原子比和洗淨次數之關係圖。 -23-The thus obtained barium titanate powders according to the above examples and comparative examples were measured for their average particle diameter, ratio of barium atoms to titanium atoms, and dielectric properties. Specifically, the average particle diameter of the barium titanate powder was determined using the BET method. In addition, the ratio of the barium atom to the titanium atom (Ba / Ti ratio) was determined by fluorescent X-ray analysis. Then, the average particle diameter was measured by using an electron microscope photograph. For Examples 1 and 2, the number of repeated decantations, that is, the number of washings, and the Ba / Ti atomic ratio at this time were determined after being crushed by a ball mill. On the other hand, the evaluation of the dielectric characteristics was performed as follows. Relative to 100 mols of barium titanate powder, 2 mol of magnesium oxide, 2 mol of hafnium oxide, 5 mol of barium carbonate, 4 mol of calcium carbonate, 3 mol of silicon oxide, 0.4 mol of carbonate, 0.05 mol of oxide, And molybdenum oxide 0 · 1 mol, by -20-200424129, these powders were wet-mixed and pulverized by a ball mill using a chromium ball for 16 hours to obtain a mixed pulverized product, which was formed under a reducing environment at 1 300 ° C. It is fired in 2 hours to form a molded body with a thickness of 1.1 mm. Thereafter, the specific dielectric constant, dielectric loss (tan δ), and temperature characteristics (TCC) of the molded body after firing were measured. (1) Use a LCR meter (1 KHz, IV) to measure the specific permittivity and dielectric loss (tan δ). (2) Regarding the temperature characteristic (TCC) of the capacitance, use an LCR meter to measure the capacitance of -5 5 ° C to 125 ° C at a measurement voltage of 1 V. Investigate whether the change rate of the capacitance is within ± 15% ( The reference temperature is within 25 ° (X7R characteristics). The results of each of the above evaluation items, that is, the average particle size, the ratio of barium atoms to titanium atoms, and the dielectric properties are shown in Tables 1, 2, and 1 and 2 As shown in the figure. Also, the atomic ratio of Example 1 in Table 1 is the time when the number of decantations is 3 times. Table 1 Average particle size (// m) Ba / Ti atomic ratio of Example 10, .2 7 1.003 Example 2 0.27 1.002 Comparative Example 1 0, .29 1.005 Comparative Example 2 0 .30 0.990 Eli-21- 200424129 Table 2 Example 1 Comparative Example 1 Comparative Example 2 Temperature (° C) Specific permittivity Electrical loss (%) TCC (° / 〇) (25 ° C reference) Dielectric constant (%) TCC (%) (25 ° C reference) Dielectric loss (%) TCC (° / 〇) (25t benchmark) -55 2737 0.95 -12.6 2609 0.89 -10.2 2700 0.90 -11.5 -30 2859 0.88 -8.7 2728 0.83 -6.1 2755 0.85 -7.0 25 3132 0.66 0.0 2905 0.57 0.0 3001 0.60 0.0 45 3084 0.58 -1.5 2879 0.53 -0.9 3011 0.55 -1.2 55 3040 0.56 -2.9 2842 0.52 -2.2 2855 0.53 -2.6 56 3003 0.56 -4.1 2809 0.52 -3.3 2862 0.53 -3.8 85 2944 0.54 -6.0 2743 0.50 -5.6 2802 0.52 -5.7 105 3001 0.52 -4.2 2769 0.49 -4.7 2812 0.50 -4.5 125 3186 0.52 1.7 2844 0.49 -2.1 2920 0.50 -2.3 135 2813 0.53 -10.2 2526 0.50 -13.0 2595 0.52 -14.5 According to Table 1, the titanium of the examples The Ba / Ti atomic comparison of the barium acid powder is close to 1.000, and it can be known that the excess barium component has been removed. The Ba / Ti atomic ratio of the barium titanate powder of Comparative Example 2 subjected to acid cleaning is 1.000 or less, and it can be known The barium component flows out excessively. From Tables 1 and 2, it can be seen that the excess barium component is more efficiently removed by washing with water (decanting) at a high temperature. From Table 2 and Figure 1, it can be seen that the barium titanate powder of the first embodiment has an excellent specific permittivity when compared with the barium titanate powder of the comparative example. [Brief description of the drawings] (I) Schematic part The first figure is a diagram showing the dielectric constant and temperature @ _ of the examples and comparative examples. -22- 200424129 Figure 2 is a graph showing the relationship between the Ba / Ti atomic ratio and the number of times of washing at room temperature and warm water (6 (TC)). -23-