JP4836307B2 - Piezoelectric ceramic composition and ink jet recording head using the same - Google Patents

Description

ここで、Ｓｒの置換比率ｘとＢａの置換比率ｙがそれぞれ０．１０より大きくなると、耐熱性が急激に低下するからであり、また、０＜x＋yとしたのは、Ｓｒ又はＢａのどちらかを置換しないと、圧電定数ｄを高めることができないからである。
【００２８】
また、（Ｚｎ_1/3 Ｓｂ_2/3）の置換比率ａが０．０８を超えたり、（Ｚｎ_1/3 Ｎｂ_2/3）の置換比率ｂが０．０４を超えると、耐熱性が低下するからであり、また、０．０１５＜a＋bとしたのは、（Ｚｎ_1/3 Ｓｂ_2/3）又は（Ｚｎ_1/3 Ｎｂ_2/3）を０．０１５以上置換しないと、圧電定数ｄを高めることができないからである。
【００２９】
さらに、（Ｎｉ_1/2 Ｔｅ_1/2）の置換比率ｃが０．０１を超えると、１５０℃のエージングによる圧電特性の劣化が著しく大きくなるからである。
【００３０】
また、Ｐｂ（Ｚｒ Ｔｉ）Ｏ₃組成系の圧電磁器組成物には、圧電定数ｄの極大値を示すＭＰＢ（組成相境界）が存在し、Ｐｂ（Ｚｒ Ｔｉ）Ｏ₃を構成するＰｂＺｒＯ₃とＰｂＴｉＯ₃ との固溶比率を変化させることにより調整することができ、例えば圧電アクチュエータ用として用いる場合には、ＭＰＢ近傍の組成値を用いることが良く、このＭＰＢは、x、a、b、cの量により変化するため、置換比率dを０．４３≦d≦０．５５とすることにより、前述した、x、a、b、cの組成範囲内でＭＰＢを捉えることができる。
【００３１】
このように、化１で表されるペロブスカイト型化合物を用いることにより、圧電定数ｄを向上させることができるだけなく、耐熱性並びに耐久性に優れた圧電磁器組成物を得ることができる。
【００３２】
また、本発明の圧電磁器組成物は、Ａｌ₂Ｏ₃及びＳｉＯ₂から成る副成分以外の残部は実質的にペロブスカイト型化合物から成る焼結体であるが、ここで、残部が実質的にペロブスカイト型化合物から成るとは、他に積極的に含有させるものはなく、不純物以外はペロブスカイト型化合物だけであることを指し、不純物として含まれるＦｅ₂Ｏ₃やＨｆＯ₂は０．０１質量％未満の範囲であれば含んでいても構わない。
【００３３】
なお、好ましいペロブスカイト型化合物の含有量としては、９９．８７質量％以上、さらには９９．９質量％以上、望ましくは９９．９３〜９９．９８質量％であることが良い。
【００３４】
次に、本発明の圧電磁器組成物の製造方法について説明する。
【００３５】
まず、出発原料として、基本成分のＰｂ₃Ｏ₄、ＺｒＯ₂、ＴｉＯ₂に、ＳｒＣＯ₃及び／又はＢａＣＯ₃と、ＺｎＯ、Ｓｂ₂Ｏ₃、ＮｉＯ、ＴｅＯ₂、Ｎｂ₂Ｏ₄の各粉末を秤量し、次いでこの混合物を脱水、乾燥したあと、８５０〜９００℃の温度で１〜３時間仮焼して、化１の組成式で表されるペロブスカイト型化合物の仮焼粉体を製作する。次に、この仮焼粉体にそれぞれＡｌ₂Ｏ₃とＳｉＯ₂を０．０１〜０．０６質量％の範囲で添加し、ボールミル等にて混合、粉砕する。その後、この粉砕物に有機バインダー（ＰＶＡ、モビニール等）を添加して混練乾燥することにより造粒粉とし、得られた造粒粉を成形して成形体を作製する。この時、焼結された圧電磁器組成物が緻密化され、表面に存在するボイドの径が大きくならないようにするために、成形圧は１×１０⁸Ｎ／ｍ²以上とすることが良い。
【００３６】
しかる後、得られた成形体を鉛雰囲気下で１〜３時間程度焼成するのであるが、この時、焼成温度が１１００℃未満であると、緻密化が不十分であるため、得られた圧電磁器組成物の機械的特性（曲げ強度や破壊靱性値）を所望の範囲とすることができず、また、１３００℃を超えると、圧電磁器組成物中のペロブスカイト型化合物の平均粒子径が所望の範囲を超えてしまう。
【００３７】
その為、１１００〜１３００℃の範囲で焼成することが良く、このようにして製作することにより本発明の圧電磁器組成物を得ることができる。
【００３８】
次に、本発明の圧電磁器組成物を用いた応用例であるインクジェット記録ヘッドを図１及び図２を基に説明する。
【００３９】
このインクジェット記録ヘッド１０は、圧電磁器組成物にダイヤモンドホイールによる研削加工にて一端が閉じられた複数の溝を並設し、各溝をインクの流路２とするとともに、流路２を構成する壁を隔壁１とした流路部材８と、上記各隔壁１の両側面上半分に、蒸着法、スパッタリング法、メッキ等の膜形成手段によって形成された、白金、金、パラジウム、ロジウム、ニッケル、アルミニウム等の金属や白金−金、パラジウム−銀、白金−パラジウム等の合金からなる駆動用電極３と、セラミックス、ガラス、シリコン等の絶縁材料から成り、各隔壁１の頂部に接着にて接合され、各流路２を覆う蓋板９と、セラミックス、ガラス、シリコン、樹脂（ポリイミド樹脂等）等から成り、上記流路部材８の開放端部に接着にて接合されたノズル板７とから成り、上記ノズル板７には、各流路２と連通し、流路２内のインクを吐出するインク吐出孔６を、上記蓋板９には、各流路２と連通し、流路２内にインクを導入するインク供給穴４をそれぞれ形成してある。
【００４０】
そして、上記流路部材８を形成する圧電磁器組成物を、Ａｌ₂Ｏ₃を０．０１〜０．０６質量％、ＳｉＯ₂を０．０１〜０．０６質量％含有し、残部が組成式Ｐｂ_1-x-yＳｒ_xＢａ_y（Ｚｎ_1/3 Ｓｂ_2/3）_a（Ｚｎ_1/3 Ｎｂ_2/3）_b（Ｎｉ_1/2 Ｔｅ_1/2）_cＺｒ_dＴｉ_{1−a−b−c−d}Ｏ₃、ただし、０≦x≦０．１０，０≦y≦０．１０，０＜x＋y，０≦a≦０．０８，０≦b≦０．０４，０≦c≦０．０１，０．０１５＜a＋b，０．４３≦d≦０．５５で示されるペロブスカイト型化合物の平均結晶粒子径が０．６〜７μｍであるとともに、４点曲げ強度が７０ＭＰａ以上、破壊靱性値が０．７ＭＰａｍ^1/2以上である焼結体により形成してある。なお、矢印は隔壁１を形成する圧電磁器組成物の分極方向を示す。
【００４１】
そして、このヘッド１０よりインク滴を吐出するには、インク供給孔４より各流路２へ顔料タイプの油性インクや水性染料インクあるいは紫外線硬化インク等のインクを導入するとともに、隔壁１に形成された駆動用電極３に電圧を印加して隔壁１を屈曲変位させ、流路２内のインクを加圧することにより、インク吐出孔６からインク滴を吐出するようになっている。
【００４２】
即ち、図２（ａ）（ｂ）にその駆動原理を示すように、例えば駆動用電極３ｂ，３ｃ及び駆動用電極３ｈ，３ｉにそれぞれ負極の電圧を、駆動用電極３ａ，３ｄ，３ｇ，３ｊに正極の電圧を印加して分極方向に対して垂直な方向に電界を加えると、隔壁１が剪断モードによるすべり振動を起こし、図２（ａ）に示すように隔壁１ａ及び隔壁１ｂが流路２ａ側へ屈曲変位するとともに、隔壁１ｄ，１ｅが流路２ｄ側へ屈曲変位するため、流路２ａ，２ｄ内に充填されたインクを加圧して、インク吐出孔６よりインク滴を吐出させることができ、この後、各駆動用電極３ａ〜３ｄ，３ｇ〜３ｊへの通電を遮断すると、屈曲変位していた隔壁１ａ，１ｂ，１ｄ，１ｅが弾性作用によって元の形状に戻り、流路２ａ，２ｄ内が減圧される結果、インク供給孔４からインクの供給が行なわれ、さらに前述した駆動用電極３ａ〜３ｄ，３ｇ〜３ｊへ極性を逆転して電圧を印加すると、図２（ｂ）に示すように隔壁１ａ，１ｂが流路２ａに対して外側へ屈曲変位するとともに、隔壁１ｄ，１ｅが流路２ｄに対して外側へ屈曲変位するため、流路２ａ，２ｄ内がさらに減圧されてインクが充填され、次に、各駆動用電極３ａ〜３ｄ，３ｇ〜３ｊへの通電を遮断すると、屈曲変位していた隔壁１ａ，１ｂ，１ｄ，１ｅが弾性作用によって元の形状に戻り、次のインク滴の吐出段階に入ることになり、これらの動作を順次繰り返すことでインク滴の吐出を連続的に行うことができる。
【００４３】
そして、本発明によれば、流路部材８を形成する圧電磁器組成物を前述した焼結体により形成してあるため、隔壁１及び流路２の形成にあたり、ダイヤモンドホイールを用いた研削加工を施しても、研削面である隔壁１の側面に割れやチッピング（欠け）等の欠陥が少ないため、幅１００μｍ以下、高さ１５０μｍ〜５００μｍ程度という薄肉の隔壁１を精度良く形成することができ、上記欠陥によって流路２内におけるインクの流れが阻害されることを防止できるため、全てのインク吐出孔からインクを安定して吐出されることができるとともに、隔壁１の屈曲変位によって割れや欠け等が発生することを防止でき、信頼性を高めることができる。
【００４４】
なお、本発明にかかるヘッド１０は、図１に示した構造だけに限定されるものではなく、本発明の要旨を逸脱しない範囲で変更や改良できることは言うまでもない。
【００４５】
【実施例】
（実施例１）
ここで、化１の組成式で表されるペロブスカイト型化合物を主成分とし、副成分としてＡｌ₂Ｏ₃及び／又はＳｉＯ₂を添加し、それらの添加量を異ならせた圧電磁器組成物と、上記副成分を含まない従来の圧電磁器組成物とを製作し、その曲げ強度、破壊靱性値、圧電定数ｄの変化、割れやチッピングの有無を調べる実験を行った。
【００４６】
まず、圧電磁器組成物の原料粉末として、Ｐｂ₃Ｏ₄、ＺｒＯ₂、ＴｉＯ₂、ＳｒＣＯ₃、ＢａＣＯ₃と、ＺｎＯ、Ｓｂ₂Ｏ₃、ＮｉＯ、ＴｅＯ₂、Ｎｂ₂Ｏ₅を用意し、それぞれの金属元素のモル比率が表１となるように秤量したものに溶媒として水を加え、ボールミルにて２０時間湿式混合した。次にこの混合物を乾燥し、９００℃の温度で３時間熱処理を加えて仮焼粉体を得た。
【００４７】
次に、得られた仮焼粉体に、表１の範囲でＡｌ₂Ｏ₃及び／又はＳｉＯ₂を添加した後、溶媒として水を加え、ＺｒＯ₂製のボールを使用しボールミルにて２０時間、湿式混合粉砕し、さらにスラリーにモビニールの有機バインダーと混練したあと乾燥させて造粒粉を作製し、１．５×１０⁸Ｎ／ｍ²の成形圧で、１００ｍｍ×１００ｍｍ、厚さ１．０ｍｍの板状の成形体を形成し、脱脂処理した後、１２５０℃前後の温度で焼成することにより、表１に示す圧電磁器組成物を得た。
【００４８】
なお、得られた各圧電磁器組成物の組成を、ＸＲＦ蛍光分析やＩＣＰ発光分光分析にて測定したところ、表１に示す組成比から構成されており、焼成による組成ずれがなかった。
【００４９】
そして、得られた圧電磁器組成物の上下面に金の電極を蒸着法により被着し、８０℃のシリコンオイル中で圧電磁器組成物の厚み方向に直流電圧を３０分間印加して、３〜５ｋＶ／ｍｍの電界にて分極処理した。その後、ダイシング装置を用いて、溝幅７０μｍ、溝深さ４００μｍ、ピッチ１４０μｍの溝加工を施し、この溝加工による複数の溝を流路とするとともに、流路を仕切る壁を隔壁とした流路部材を製作した。なお、加工に使用したダイヤホイールは、砥粒粒度＃２０００（４〜８μｍ）であり、回転数２５０００ｒｐｍ、送り速度２０ｍｍ／秒の条件にて研削加工を行った。
【００５０】
その後、隔壁の割れやチッピングの有無を双眼顕微鏡にて観察し、また、圧電磁器組成物を形成する各ペロブスカイト型化合物の平均結晶粒子径は、焼結体表面又は断面をＳＥＭ（電子顕微鏡）により写真を撮影し、インターセプト法により平均結晶粒径を測定し、４点曲げ強度はＪＩＳ Ｒ１６０１に準拠して測定し、破壊靱性値は、ＪＩＳ Ｒ１６０７に準拠して測定し、圧電定数ｄ（ｄ₁₅）は、分極処理した厚さ０．２５ｍｍ、幅２．５ｍｍ、長さ１０ｍｍの短冊状の試料を電子工業会（ＥＭＡＳ）の規格に基づく測定法によって測定した。
【００５１】
それぞれの結果は表１に示す通りである。なお、圧電定数ｄ₁₅は、Ａｌ₂Ｏ₃及びＳｉＯ₂を添加していない試料の圧電定数ｄ（ｄ₁₅）を１００とした場合の相対値で示した。
【００５２】
【表１】

【００５３】
この結果、表１に見られるように、組成式Ｐｂ_1-x-yＳｒ_xＢａ_y（Ｚｎ_1/3 Ｓｂ_2/3）_a（Ｚｎ_1/3 Ｎｂ_2/3）_b（Ｎｉ_1/2 Ｔｅ_1/2）_cＺｒ_dＴｉ_{1−a−b−c−d}Ｏ₃、ただし、０≦x≦０．１０，０≦y≦０．１０，０＜x＋y，０≦a≦０．０８，０≦b≦０．０４，０≦c≦０．０１，０．０１５＜a＋b，０．４３≦d≦０．５５で示されるペロブスカイト型化合物を主成分とし、副成分としてＡｌ₂Ｏ₃を０．０１〜０．０６質量％、ＳｉＯ₂を０．０１〜０．０６質量％含有して成り、上記ペロブスカイト型化合物の平均結晶粒子径が０．６〜７μｍであるとともに、４点曲げ強度が７０ＭＰａ以上で、かつ破壊靱性値が０．７ＭＰａｍ^1/2以上である圧電磁器組成物であれば、Ａｌ₂Ｏ₃及びＳｉＯ₂の副成分を含有していない従来の圧電磁器組成物と同等あるいはそれ以上の圧電定数ｄが得られるとともに、研削加工を施しても隔壁に割れがなくかつ大きなチッピングを生じることもなく、研削性に優れることが判る。
（実施例２）次に、表１のうち、試料Ｎｏ．５、９、１２、２５、３５の流路部材を用い、各流路部材の隔壁の両側面上半分にスパッタリング法にて白金からなる駆動用電極を形成し、しかる後、インク供給孔を備えたアルミナセラミック製の蓋板を、流路部材の各流路を塞ぐように隔壁の頂部にエポキシ系樹脂により接着するとともに、流路部材の開放端部に、各流路と連通するインク吐出孔を備えたポリイミド樹脂製のノズル板をエポキシ系樹脂にて接着して図１に示すヘッドを製作した。なお、本発明範囲外のものは、流路部材の隔壁に割れが無いものを用意してヘッドを製作した。
【００５４】
そして、各ヘッドの流路内にインクを充填し、駆動用電極に２０Ｖの電圧を１００Ｈｒ印加してインク吐出孔よりインク滴を吐出させ、この時のインク滴の飛翔状況を放電管を光源としフィルム上に記録させる高速度写真撮影装置によって観察した。
【００５５】
この結果、試料Ｎｏ．９の流路部材を用いて形成した本発明範囲外のヘッドは、１００Ｈｒ経過後、１００個のインク吐出孔のうち２６個のインク吐出孔からインク滴が吐出されなくなり、試料Ｎｏ．１２の流路部材を用いて形成した本発明範囲外のヘッドでは、１００Ｈｒ経過後、１００個のインク吐出孔のうち１５個のインク吐出孔からインク滴が吐出されなくなった。そこで、試料Ｎｏ．９，１２の圧電磁器組成物から成る流路部材を用いたヘッドを切断して隔壁の状況を確認したところ、インク滴が吐出されなかったインク吐出孔と連通する流路を構成する隔壁にクラックや欠け等が見られた。
【００５６】
これに対し、試料Ｎｏ．５，２５，３５の流路部材を用いて形成した本発明のヘッドは、１００Ｈｒ経過後も、１００個のインク吐出孔全てから安定してインク滴を吐出させることができ、また、各ヘッドを切断して隔壁の状況を確認したところ、隔壁に欠陥は見られなかった。
【００５７】
【発明の効果】
以上のように、本発明によれば、Ａｌ₂Ｏ₃を０．０１〜０．０６質量％、ＳｉＯ₂を０．０１〜０．０６質量％含有し、残部が組成式Ｐｂ_1-x-yＳｒ_xＢａ_y（Ｚｎ_1/3 Ｓｂ_2/3）_a（Ｚｎ_1/3 Ｎｂ_2/3）_b（Ｎｉ_1/2 Ｔｅ_1/2）_cＺｒ_dＴｉ_{1−a−b−c−d}Ｏ₃、ただし、０≦x≦０．１０，０≦y≦０．１０，０＜x＋y，０≦a≦０．０８，０≦b≦０．０４，０≦c≦０．０１，０．０１５＜a＋b，０．４３≦d≦０．５５で示されるペロブスカイト型化合物から成り、上記ペロブスカイト型化合物の平均結晶粒子径が０．６〜７μｍであるとともに、４点曲げ強度が７０ＭＰａ以上、破壊靱性値が０．７ＭＰａｍ^1/2以上である焼結体により圧電磁器組成物を構成したことから、上記ペロブスカイト型化合物から成る従来の圧電磁器組成物と同等又はそれ以上の圧電定数ｄが得られ、大きな機械的変位量が要求される圧電アクチュエータ用として好適に用いることができるとともに、ダイヤモンドホイールを用いた研削加工を施したとしても割れやチッピング（欠け）等の欠陥がなく、研削性を大幅に向上させることができる。
【００５８】
また、少なくとも一部が前記圧電磁器組成物から成る複数の隔壁を並設し、各隔壁間をインクの流路として成る流路部材と、上記隔壁の両側面にそれぞれ形成された駆動用電極と、前記隔壁の頂面に接合され、上記流路を覆う蓋板と、上記各流路と連通するインク吐出孔とからインクジェット記録ヘッドを構成したことから、隔壁に割れやチッピング（欠け）等の欠陥がなく、隔壁の屈曲変位によって破損することも少ないため、インク滴の吐出性能を高めることができるとともに、長期間にわたり、安定してインク滴を吐出させることができる。
【図面の簡単な説明】
【図１】本発明の圧電磁器組成物を用いたインクジェット記録ヘッドの一例を示す一部を破断した斜視図である。
【図２】（ａ）（ｂ）は本発明のインクジェット記録ヘッドの駆動原理を説明するための断面図である。
【図３】従来のインクジェット記録ヘッドの一例を示す一部を破断した斜視図である。
【符号の説明】
１，２１・・・隔壁 ２，２２・・・流路 ３，２３・・・駆動用電極
４，２４・・・インク供給孔 ５，２５・・・インク吐出孔
６，２６・・・ノズル板 ７，２７・・・流路部材 ８，２８・・・蓋板
１０，３０・・・インクジェット記録ヘッド[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a lead zirconate titanate piezoelectric ceramic composition excellent in grindability without deteriorating a piezoelectric constant d, and an ink jet recording head using the same.
[0002]
[Prior art]
Conventionally, there are ultrasonic applied vibrators, ultrasonic motors, piezoelectric actuators, and the like that use displacement generated by the piezoelectric effect as a mechanical drive source, and are attracting attention as the mechatronics field advances.
[0003]
For example, the piezoelectric actuator has excellent power consumption and heat generation, excellent response speed, large displacement, small dimensions and weight compared to a conventional electromagnetic actuator in which a coil is wound around a magnetic material. It has the characteristics. As a piezoelectric material constituting these piezoelectric actuators, etc., PbZrO_Three-PbTiO_Three(Hereafter, Pb (Zr Ti) O_ThreeThe composition type piezoelectric ceramic composition is used, and it is required that a larger mechanical displacement be obtained. For this purpose, a piezoelectric ceramic composition having a large piezoelectric constant d is desired.
[0004]
As a piezoelectric ceramic composition meeting such a purpose, for example, Pb (ZrTi) O_ThreeAs a third component, Pb (Mg_1/3  Nb_2/3) O_Three, Pb (Ni_1/3  Nb_2/3) O_Three, Pb (Zn_1/3  Nb_2/3) O_ThreeA sintered body made of a perovskite type compound in which at least one of these is dissolved is put into practical use. Japanese Patent Laid-Open No. 5-58729 discloses that the perovskite type compound is a main component and subcomponents are NiO, CuO, Bi for the purpose of improving heat resistance and sintering properties in addition to piezoelectric characteristics.₂O_Three, WO_ThreeA piezoelectric ceramic composition containing at least one of the above in a range of 0.01 to 3 mol% is disclosed.
[0005]
On the other hand, in recent years, an ink jet recording apparatus has been used as a recording apparatus that prints color images, character information, and the like at a low running cost, and a piezoelectric actuator is used in an ink jet recording head mounted on the recording apparatus. .
[0006]
As shown in FIG. 3 as an example of a conventional ink jet recording head, the ink jet recording head 20 (hereinafter simply referred to as a head) has a plurality of grooves whose one ends are closed by grinding with a diamond wheel in a piezoelectric ceramic composition. A flow path member 28 in which the grooves are used as the ink flow paths 22 and the walls constituting the flow paths 22 are the partition walls 21, and the driving electrodes formed on the upper halves on both side surfaces of the partition walls 21. 23, a lid plate 29 that is bonded to the top of each partition wall 21 and covers each flow path 22, and a nozzle plate 27 that is bonded to the open end of the flow path member 28. The nozzle plate 27 is formed with an ink discharge hole 26 that communicates with each flow path 22 and discharges ink in the flow path 22, and the lid plate 29 communicates with each flow path 22 and within the flow path 22. Ink supply hole 2 for introducing ink into There were those formed. The arrow indicates the polarization direction of the piezoelectric ceramic composition forming the partition wall 21.
[0007]
In order to eject ink droplets from the head 20, ink is introduced into the flow paths 22 from the ink supply holes 24, and the partition walls 21 are bent and displaced by energizing the drive electrodes 23 provided on the partition walls 21. In order to enhance the ink droplet ejection performance, the ink in the flow path 22 partitioned between the partition walls 21 is pressurized and ink droplets are ejected from the ink ejection holes 6 communicating with the flow path 22. Since it is necessary to increase the mechanical displacement of the partition wall 21, Pb (Zr Ti) O is used as a piezoelectric ceramic composition for forming the flow path member 28._ThreeA composition-type piezoelectric ceramic composition was used.
[0008]
[Problems to be solved by the invention]
However, in order to obtain a high piezoelectric constant d, Pb (Zr Ti) O_ThreeFor the composition system, a part of (Zr Ti) is replaced with Pb (Zn_1/3  Sb_2/3) O_Three, Pb (Zn_1/3  Nb_2/3) O_Three, Pb (Ni_1/2  Te_1/2) O_ThreeWhen a piezoelectric ceramic composition composed of a perovskite type compound substituted with one or more components among them is subjected to grinding, there is a problem that defects due to bending or chipping (chips) are likely to occur and the processing accuracy is poor.
[0009]
The reason for this is not clear. Since the ratio of the piezoelectric ceramic composition in contact with the ground surface is large and a large stress is applied to the ground surface, this stress will cause cracks in the ground surface, which may cause defects such as cracking and chipping. It is.
[0010]
Further, since the partition wall 21 that partitions the flow path 22 of the ink jet recording head 20 is thin with a width of 100 μm or less and a height of 150 μm or more, the flow path member 28 is a piezoelectric ceramic composition made of the perovskite compound. When the partition wall 21 and the flow path 22 are formed by grinding using a diamond wheel, there is a problem that the partition wall 21 has many defects such as cracks and chipping (chips), resulting in poor yield. Moreover, even if the head 20 is manufactured as it is after grinding, defects are not visible after grinding, and if the partition wall 21 is bent and displaced by energizing the driving electrode 23 to eject ink droplets, Since there is an invisible defect, there is a problem that the partition wall 21 is damaged during use, and ink droplets cannot be ejected stably.
[0011]
[Means for Solving the Problems]
  Therefore, in view of the above problems, the present invention provides Al.₂O_Three0.01 to 0.06quality%, SiO₂0.01 to 0.06quality% By weight, the balance being the composition formula Pb_1-xySr_xBa_y(Zn_1/3  Sb_2/3)_a(Zn_1/3  Nb_2/3)_b(Ni_1/2  Te_1/2)_cZr_dTi_{1−a−b−c−d}O_ThreeHowever, 0 ≦ x ≦ 0.10, 0 ≦ y ≦ 0.10, 0 <x + y, 0 ≦ a ≦ 0.08, 0 ≦ b ≦ 0.04, 0 ≦ c ≦ 0.01, 0.015 <a + b, consisting of a perovskite compound represented by 0.43 ≦ d ≦ 0.55, the average crystal particle diameter of the perovskite compound is 0.6 to 7 μm, and the four-point bending strength is 70 MPa or more. Toughness value is 0.7 MPam^1/2A piezoelectric ceramic composition is constituted by the sintered body described above.
[0012]
In the present invention, a plurality of partition walls, at least a part of which are made of the piezoelectric ceramic composition, are provided side by side, and are formed on both side surfaces of the partition wall, each of which forms an ink channel between the partition walls. An ink jet recording head is composed of a driving electrode, a lid plate joined to the top surface of the partition wall and covering the flow path, and ink discharge holes communicating with the flow paths.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described.
[0014]
  The piezoelectric ceramic composition of the present invention contains Al as a secondary component.₂O_ThreeAnd SiO₂With the balance being the composition formula Pb_1-xySr_xBa_y(Zn_1/3  Sb_2/3)_a(Zn_1/3  Nb_2/3)_b(Ni_1/2  Te_1/2)_cZr_dTi_{1−a−b−c−d}O_ThreeHowever, 0 ≦ x ≦ 0.10, 0 ≦ y ≦ 0.10, 0 <x + y, 0 ≦ a ≦ 0.08, 0 ≦ b ≦ 0.04, 0 ≦ c ≦ 0.01, 0.0A sintered body made of a perovskite compound represented by 15 <a + b, 0.43 ≦ d ≦ 0.55, wherein the average crystal particle diameter of the perovskite compound is 0.6 to 7 μm .
[0015]
  Al contained as an accessory component₂O_ThreeAnd SiO₂ WhenIs easy to generate a liquid phase at the grain boundary in the sintering stage, and after the sintering is finished, PbO-SiO₂-Al₂O_ThreeIn order to form a glass phase mainly composed of the above, it is possible to densify the sintered body at a lower temperature than a piezoelectric ceramic composition not containing these subcomponents, and to grow crystals of the perovskite type compound. Therefore, the contact area between the diamond wheel and the ground surface of the piezoelectric ceramic composition can be reduced during grinding with a diamond hole or the like, and the stress acting on the ground surface can be reduced.
[0016]
In addition, the PbO-SiO₂-Al₂O_ThreeSince the glass phase mainly composed of is stronger than the perovskite type compound, the fracture toughness value of the sintered body can be increased.
[0017]
  ThatForThe piezoelectric ceramic composition of the present invention can greatly improve the grindability by improving the fracture toughness value and reducing the contact area with the diamond hole with less cracking and chipping (chipping) during grinding. At the same time, since firing at a low temperature is possible, a special firing furnace is not necessary, and a commonly used firing furnace can be used, which can be manufactured at low cost.
[0018]
  By the way, in order to obtain such an effect, as a secondary component, Al₂O_ThreeAnd SiO₂In addition to containing both components, Al₂O_Three0.01 to 0.06qualityIn a range of% by weight and SiO₂0.01 to 0.06qualityIt is important to contain in the range of the amount%.
[0019]
That is, the secondary component is Al₂O_ThreeBy itself, the strength of the grain boundary phase is too large compared to the perovskite type compound, and the fracture mechanism gives priority to intragranular fracture over intergranular fracture, so it is not possible to reduce cracking and chipping during chipping And the subcomponent is SiO.₂By itself, the bending strength of the sintered body is low, and cracks and chipping (chips) during grinding cannot be reduced. Note that the intragranular fracture means that the fracture progresses inside the crystal grains made of the perovskite type compound, and the intergranular fracture means that the fracture progresses along the grain boundary of the sintered body.
[0020]
  Al₂O_ThreeAnd SiO₂Content of 0.01 to 0.06 respectivelyqualityThe amount% is Al₂O_ThreeOr SiO₂The content of 0.01qualityIf the amount is less than%, the effect of growing perovskite type compound crystals is small and the contact area with the diamond wheel during grinding is large, so the stress acting during grinding cannot be reduced, and cracks and This is because defects such as chipping (chips) cannot be reduced.₂O_ThreeOr SiO₂Content of 0.06qualityIf the amount exceeds 50%, the strength of the grain boundary phase composed of the glass phase becomes greater than the strength of the perovskite type compound, so that the intragranular fracture is more dominant than the grain boundary fracture on the ground surface. Defects such as chipping) cannot be reduced, and Al₂O_ThreeAnd SiO₂Content of 0.06 eachqualityThis is because the piezoelectric constant d of the piezoelectric ceramic composition is greatly reduced when the amount is more than%.
[0021]
  Preferably, Al₂O_ThreeAnd SiO₂0.01 to 0.04 respectivelyqualityIt is good to contain in the range of the amount%.
[0022]
Moreover, in order to reduce the stress which acts at the time of grinding, it is necessary for the average crystal particle diameter of a perovskite type compound to exist in the range of 0.6-7 micrometers.
[0023]
That is, Al which is a subsidiary component₂O_ThreeAnd SiO₂Even if the average particle size of the perovskite type compound is less than 0.6 μm, the contact area with the diamond wheel is large during grinding, and the stress acting during grinding cannot be reduced. Conversely, if the average crystal particle size of the perovskite type compound exceeds 7 μm, the chipping size when chipping (chip) occurs is too large.
[0024]
Preferably, the average crystal particle diameter of the perovskite type compound is 0.6 to 5 μm.
[0025]
Furthermore, the piezoelectric ceramic composition of the present invention has a sintered body having a four-point bending strength of 70 MPa or more and a fracture toughness value of 0.7 MPam.^1/2It is the above.
[0026]
Here, the 4-point bending strength is 70 MPa or more, and the fracture toughness value is 0.7 MPam.^1/2Even if the content of the subcomponent and the average crystal particle diameter of the perovskite type compound are within the above-mentioned range, the four-point bending strength of the sintered body is less than 70 MPa, or the fracture toughness value is 0.7 MPam^1/2If it is less than the above, defects such as cracks and chipping (chips) during grinding cannot be reduced, and preferably the 4-point bending strength is 75 MPa or more and the fracture toughness value is 0.75 MPam.^1/2It is good to be above.
[0027]
  By the way, it is important that the perovskite type compound constituting the main component of the piezoelectric ceramic composition of the present invention is represented by the composition formula (1).
[Chemical 1]

Here, when the substitution ratio x of Sr and the substitution ratio y of Ba are each larger than 0.10, the heat resistance is drastically reduced, and 0 <x + y is set to either Sr or Ba. This is because the piezoelectric constant d cannot be increased without replacing.
[0028]
  Also, (Zn_1/3  Sb_2/3) Substitution ratio a exceeds 0.08, or (Zn_1/3  Nb_2/3This is because when the substitution ratio b of () exceeds 0.04, the heat resistance decreases, and 0.015 <a + b is set to (Zn_1/3  Sb_2/3) Or (Zn_1/3  Nb_2/3This is because the piezoelectric constant d cannot be increased unless 0.015 or more is substituted.
[0029]
  further, (Ni_1/2  Te_1/2This is because the deterioration of the piezoelectric characteristics due to aging at 150 ° C. is significantly increased when the substitution ratio c of () exceeds 0.01.
[0030]
  Pb (Zr Ti) O_ThreeIn the composition-type piezoelectric ceramic composition, there is MPB (composition phase boundary) indicating the maximum value of the piezoelectric constant d, and Pb (Zr Ti) O_ThreeOf PbZrO_ThreeAnd PbTiO_Three WhenFor example, when used for a piezoelectric actuator, it is preferable to use a composition value in the vicinity of the MPB, and this MPB depends on the amounts of x, a, b, and c. Therefore, by setting the substitution ratio d to 0.43 ≦ d ≦ 0.55, MPB can be captured within the composition range of x, a, b, and c described above.
[0031]
Thus, by using the perovskite type compound represented by Chemical Formula 1, it is possible not only to improve the piezoelectric constant d, but also to obtain a piezoelectric ceramic composition excellent in heat resistance and durability.
[0032]
  Moreover, the piezoelectric ceramic composition of the present invention contains Al.₂O_ThreeAnd SiO₂The remainder other than the subcomponent consisting of is a sintered body substantially composed of a perovskite type compound, but here, the remainder consists essentially of a perovskite type compound, there is no other positively contained, Except for impurities, it means only perovskite type compounds, and Fe contained as impurities₂O_ThreeAnd HfO₂Is 0.01qualityIt may be included as long as it is less than the amount%.
[0033]
  The preferable perovskite type compound content is 99.87.quality% Or more, and further 99.9quality% Or more, preferably 99.93 to 99.98qualityIt is good that the amount is%.
[0034]
Next, the manufacturing method of the piezoelectric ceramic composition of this invention is demonstrated.
[0035]
  First, as a starting material, the basic component Pb_ThreeO_Four, ZrO₂TiO₂And SrCO_ThreeAnd / or BaCO_ThreeZnO, Sb₂O_Three, NiO, TeO₂, Nb₂O_FourNext, after dehydrating and drying this mixture, the mixture was calcined at a temperature of 850 to 900 ° C. for 1 to 3 hours to obtain a calcined powder of a perovskite type compound represented by the chemical formula 1 Is produced. Next, each of the calcined powders is made of Al.₂O_ThreeAnd SiO₂0.01 to 0.06qualityAdd in the range of% by weight, mix and grind with a ball mill or the like. Thereafter, an organic binder (PVA, mobile vinyl, etc.) is added to this pulverized product and kneaded and dried to form granulated powder, and the obtained granulated powder is molded to produce a molded body. At this time, in order to prevent the sintered piezoelectric ceramic composition from being densified and to increase the diameter of voids existing on the surface, the molding pressure is 1 × 10.⁸N / m²It is good to be above.
[0036]
Thereafter, the obtained molded body is fired in a lead atmosphere for about 1 to 3 hours. At this time, if the firing temperature is less than 1100 ° C., densification is insufficient. The mechanical properties (bending strength and fracture toughness value) of the porcelain composition cannot be in the desired ranges, and if it exceeds 1300 ° C., the average particle size of the perovskite type compound in the piezoelectric ceramic composition is desired. It will be out of range.
[0037]
Therefore, it is preferable to fire in the range of 1100 to 1300 ° C. The piezoelectric ceramic composition of the present invention can be obtained by manufacturing in this way.
[0038]
Next, an ink jet recording head as an application example using the piezoelectric ceramic composition of the present invention will be described with reference to FIGS.
[0039]
This ink jet recording head 10 includes a plurality of grooves whose ends are closed by grinding with a diamond wheel in a piezoelectric ceramic composition, and each groove serves as an ink flow path 2 and constitutes the flow path 2. Platinum, gold, palladium, rhodium, nickel, formed by film forming means such as a vapor deposition method, a sputtering method, or plating on the flow path member 8 with the wall as the partition wall 1 and the upper half on both sides of each partition wall 1 It consists of a drive electrode 3 made of a metal such as aluminum or an alloy such as platinum-gold, palladium-silver, platinum-palladium, and an insulating material such as ceramics, glass, silicon, etc., and is bonded to the top of each partition wall 1 by adhesion. And a cover plate 9 covering each flow path 2 and a nose made of ceramics, glass, silicon, resin (polyimide resin, etc.), etc., and bonded to the open end of the flow path member 8 by bonding. The nozzle plate 7 communicates with each flow path 2, and ink discharge holes 6 for discharging ink in the flow path 2. The lid plate 9 communicates with each flow path 2. Ink supply holes 4 for introducing ink into the flow path 2 are formed.
[0040]
  And the piezoelectric ceramic composition forming the flow path member 8 is made of Al.₂O_Three0.01 to 0.06quality%, SiO₂0.01 to 0.06quality% By weight, the balance being the composition formula Pb_1-xySr_xBa_y(Zn_1/3  Sb_2/3)_a(Zn_1/3  Nb_2/3)_b(Ni_1/2  Te_1/2)_cZr_dTi_{1−a−b−c−d}O_ThreeHowever, 0 ≦ x ≦ 0.10, 0 ≦ y ≦ 0.10, 0 <x + y, 0 ≦ a ≦ 0.08, 0 ≦ b ≦ 0.04, 0 ≦ c ≦ 0.01, 0.0The average crystal particle diameter of the perovskite type compound represented by 15 <a + b, 0.43 ≦ d ≦ 0.55 is 0.6 to 7 μm, the four-point bending strength is 70 MPa or more, and the fracture toughness value is 0.7 MPam.^1/2The sintered body is formed as described above. The arrow indicates the polarization direction of the piezoelectric ceramic composition forming the partition wall 1.
[0041]
In order to eject ink droplets from the head 10, an ink such as pigment-type oil-based ink, water-based dye ink, or ultraviolet curable ink is introduced into each flow path 2 from the ink supply hole 4, and is formed in the partition wall 1. Ink droplets are ejected from the ink ejection holes 6 by applying a voltage to the driving electrode 3 to bend and displace the partition wall 1 and pressurize the ink in the flow path 2.
[0042]
That is, as shown in FIGS. 2 (a) and 2 (b), for example, the driving electrodes 3b, 3c and the driving electrodes 3h, 3i are respectively supplied with negative voltages and the driving electrodes 3a, 3d, 3g, 3j. When a positive voltage is applied to the electrode and an electric field is applied in a direction perpendicular to the polarization direction, the partition wall 1 undergoes sliding vibration in a shear mode, and the partition wall 1a and the partition wall 1b are flow channels as shown in FIG. Since the partition walls 1d and 1e are bent and displaced toward the flow path 2d while being bent and displaced toward the 2a side, the ink filled in the flow paths 2a and 2d is pressurized and ink droplets are ejected from the ink ejection holes 6. After that, when the energization to each of the driving electrodes 3a to 3d and 3g to 3j is cut off, the partition walls 1a, 1b, 1d, and 1e that have been bent and displaced return to their original shapes by elastic action, and the flow path 2a , 2d is depressurized, resulting in ink When ink is supplied from the supply hole 4 and a voltage is applied to the driving electrodes 3a to 3d and 3g to 3j with the polarity reversed, the partition walls 1a and 1b flow as shown in FIG. Since the partition walls 1d and 1e are bent and displaced outward with respect to the path 2a, the channels 2a and 2d are further depressurized and filled with ink. When the drive electrodes 3a to 3d and 3g to 3j are de-energized, the partition walls 1a, 1b, 1d, and 1e that have been bent and displaced return to their original shapes due to the elastic action and enter the ejection stage of the next ink droplet. Thus, the ink droplets can be ejected continuously by repeating these operations sequentially.
[0043]
And according to this invention, since the piezoelectric ceramic composition which forms the flow-path member 8 is formed with the sintered compact mentioned above, in the formation of the partition 1 and the flow path 2, the grinding process using a diamond wheel is carried out. Even if applied, since there are few defects such as cracks and chipping (chips) on the side surface of the partition wall 1 which is a grinding surface, the thin partition wall 1 having a width of 100 μm or less and a height of about 150 μm to 500 μm can be accurately formed. Since the ink flow in the flow path 2 can be prevented from being obstructed by the defects, the ink can be stably ejected from all the ink ejection holes, and cracks, chips, etc. are caused by the bending displacement of the partition wall 1. Can be prevented and reliability can be improved.
[0044]
Needless to say, the head 10 according to the present invention is not limited to the structure shown in FIG. 1 and can be changed or improved without departing from the gist of the present invention.
[0045]
【Example】
Example 1
Here, the main component is a perovskite compound represented by the chemical formula of Chemical Formula 1, and Al is used as a subcomponent.₂O_ThreeAnd / or SiO₂And a conventional piezoelectric ceramic composition that does not contain the above-mentioned auxiliary components, and its bending strength, fracture toughness value, change in piezoelectric constant d, cracking An experiment was conducted to check the presence or absence of chipping.
[0046]
First, as a raw material powder of a piezoelectric ceramic composition, Pb_ThreeO_Four, ZrO₂TiO₂, SrCO_Three, BaCO_ThreeZnO, Sb₂O_Three, NiO, TeO₂, Nb₂O_FiveWas prepared, and water was added as a solvent to those weighed so that the molar ratios of the respective metal elements were as shown in Table 1, followed by wet mixing in a ball mill for 20 hours. Next, this mixture was dried and heat treated at 900 ° C. for 3 hours to obtain a calcined powder.
[0047]
Next, the obtained calcined powder was mixed with Al within the range shown in Table 1.₂O_ThreeAnd / or SiO₂Is added, water is added as a solvent, and ZrO is added.₂Wet and pulverize with a ball mill for 20 hours using a ball made of the product, and then knead the slurry with an organic binder of vinyl and dry it to produce granulated powder, 1.5 × 10⁸N / m²A piezoelectric ceramic composition shown in Table 1 is obtained by forming a plate-like molded body having a size of 100 mm × 100 mm and a thickness of 1.0 mm, degreasing treatment, and firing at a temperature of about 1250 ° C. It was.
[0048]
In addition, when the composition of each obtained piezoelectric ceramic composition was measured by XRF fluorescence analysis or ICP emission spectroscopic analysis, it was composed of the composition ratios shown in Table 1, and there was no composition shift due to firing.
[0049]
Then, gold electrodes were deposited on the upper and lower surfaces of the obtained piezoelectric ceramic composition by vapor deposition, and a DC voltage was applied in the thickness direction of the piezoelectric ceramic composition in 80 ° C. silicon oil for 3 minutes. Polarization treatment was performed in an electric field of 5 kV / mm. Thereafter, using a dicing apparatus, a groove having a groove width of 70 μm, a groove depth of 400 μm, and a pitch of 140 μm is provided. A member was produced. The diamond wheel used for processing was abrasive grain size # 2000 (4 to 8 μm), and grinding was performed under the conditions of a rotational speed of 25000 rpm and a feed rate of 20 mm / second.
[0050]
Thereafter, the presence or absence of cracks or chipping of the partition walls was observed with a binocular microscope, and the average crystal particle diameter of each perovskite type compound forming the piezoelectric ceramic composition was determined by measuring the surface or cross section of the sintered body with an SEM (electron microscope). A photograph is taken, the average crystal grain size is measured by the intercept method, the four-point bending strength is measured according to JIS R1601, the fracture toughness value is measured according to JIS R1607, and the piezoelectric constant d (d₁₅), A strip-shaped sample having a thickness of 0.25 mm, a width of 2.5 mm, and a length of 10 mm was measured by a measuring method based on the standards of the Electronic Industries Association (EMAS).
[0051]
Each result is as shown in Table 1. The piezoelectric constant d₁₅Al₂O_ThreeAnd SiO₂The piezoelectric constant d (d₁₅) Is shown as a relative value when 100 is assumed.
[0052]
[Table 1]

[0053]
  As a result, as shown in Table 1, the composition formula Pb_1-xySr_xBa_y(Zn_1/3  Sb_2/3)_a(Zn_1/3  Nb_2/3)_b(Ni_1/2  Te_1/2)_cZr_dTi_{1−a−b−c−d}O_ThreeHowever, 0 ≦ x ≦ 0.10, 0 ≦ y ≦ 0.10, 0 <x + y, 0 ≦ a ≦ 0.08, 0 ≦ b ≦ 0.04, 0 ≦ c ≦ 0.01, 0.0The main component is a perovskite compound represented by 15 <a + b, 0.43 ≦ d ≦ 0.55, and Al is used as a subcomponent.₂O_Three0.01 to 0.06quality%, SiO₂0.01 to 0.06qualityThe perovskite type compound has an average crystal particle diameter of 0.6 to 7 μm, a four-point bending strength of 70 MPa or more, and a fracture toughness value of 0.7 MPam.^1/2If the piezoelectric ceramic composition is the above, Al₂O_ThreeAnd SiO₂A piezoelectric constant d equal to or higher than that of a conventional piezoelectric ceramic composition that does not contain the above-mentioned subcomponents can be obtained, and even if grinding is performed, the partition wall is not cracked and large chipping does not occur. It is understood that it is excellent.
(Example 2) Next, in Table 1, sample No. 5, 9, 12, 25, and 35 channel members are used, and driving electrodes made of platinum are formed by sputtering on the upper half of both side surfaces of the partition walls of each channel member, and then ink supply holes are provided. The alumina ceramic lid plate is adhered to the top of the partition wall with an epoxy-based resin so as to block each flow path of the flow path member, and the ink discharge hole communicating with each flow path at the open end of the flow path member A nozzle plate made of polyimide resin provided with was bonded with an epoxy resin to produce a head shown in FIG. In addition, the thing outside the range of this invention prepared the thing without a crack in the partition of a flow-path member, and manufactured the head.
[0054]
Then, ink is filled in the flow path of each head, a voltage of 20 V is applied to the driving electrode for 100 hours to eject ink droplets from the ink ejection holes, and the flying state of the ink droplets at this time is determined using the discharge tube as a light source. Observations were made with a high-speed photography device that was recorded on film.
[0055]
As a result, sample no. In the head outside the range of the present invention formed using the flow path member of No. 9, ink droplets are not ejected from 26 of the 100 ink ejection holes after 100 hours have passed. In a head outside the range of the present invention formed using 12 flow path members, ink droplets were not discharged from 15 of the 100 ink discharge holes after 100 hours had elapsed. Therefore, sample no. When the head using the channel member composed of the piezoelectric ceramic composition of Nos. 9 and 12 was cut and the condition of the partition wall was confirmed, the partition wall constituting the channel communicating with the ink discharge hole where the ink droplet was not discharged cracked. And chipping were observed.
[0056]
In contrast, sample no. The head of the present invention formed using 5, 25, and 35 flow path members can stably eject ink droplets from all 100 ink ejection holes even after 100 hours have passed. When the state of the partition walls was confirmed by cutting, no defects were found in the partition walls.
[0057]
【The invention's effect】
  As described above, according to the present invention, Al₂O_Three0.01 to 0.06quality%, SiO₂0.01 to 0.06quality% By weight, the balance being the composition formula Pb_1-xySr_xBa_y(Zn_1/3  Sb_2/3)_a(Zn_1/3  Nb_2/3)_b(Ni_1/2  Te_1/2)_cZr_dTi_{1−a−b−c−d}O_ThreeHowever, 0 ≦ x ≦ 0.10, 0 ≦ y ≦ 0.10, 0 <x + y, 0 ≦ a ≦ 0.08, 0 ≦ b ≦ 0.04, 0 ≦ c ≦ 0.01, 0.015 <a + b, consisting of a perovskite compound represented by 0.43 ≦ d ≦ 0.55, the average crystal particle diameter of the perovskite compound is 0.6 to 7 μm, and the four-point bending strength is 70 MPa or more. Toughness value is 0.7 MPam^1/2Since the piezoelectric ceramic composition is composed of the above sintered body, a piezoelectric constant d equal to or higher than that of the conventional piezoelectric ceramic composition made of the perovskite type compound can be obtained, and a large mechanical displacement is required. In addition, it can be suitably used for a piezoelectric actuator, and even if a grinding process using a diamond wheel is performed, there is no defect such as cracking or chipping, and the grindability can be greatly improved.
[0058]
Also, a plurality of partition walls, at least part of which are made of the piezoelectric ceramic composition, are arranged side by side, and a flow path member is formed between each partition wall as an ink flow path, and driving electrodes respectively formed on both side surfaces of the partition wall. Since the ink jet recording head is composed of a lid plate that is bonded to the top surface of the partition wall and covers the flow path, and an ink discharge hole that communicates with the flow path, the partition wall may be cracked or chipped. Since there is no defect and it is less likely to be damaged by the bending displacement of the partition wall, the ink droplet ejection performance can be improved and the ink droplets can be ejected stably over a long period of time.
[Brief description of the drawings]
FIG. 1 is a partially broken perspective view showing an example of an ink jet recording head using a piezoelectric ceramic composition of the present invention.
2A and 2B are cross-sectional views for explaining the driving principle of the ink jet recording head of the present invention.
FIG. 3 is a partially broken perspective view showing an example of a conventional ink jet recording head.
[Explanation of symbols]
1, 21 ... partition wall 2, 22 ... flow path 3, 23 ... drive electrode
4, 24 ... Ink supply holes 5, 25 ... Ink discharge holes
6, 26 ... Nozzle plate 7, 27 ... Channel member 8, 28 ... Lid plate
10, 30 ... Inkjet recording head

Claims (2)

Al ₂ O ₃ and 0.01 to 0.06 mass%, the SiO ₂ containing 0.01 to 0.06 mass%, the balance composition formula _{Pb 1-xy Sr x Ba y} (Zn 1/3 Sb _2/3 ) _a (Zn _1/3 Nb _2/3 ) _b (Ni _1/2 Te _1/2 ) _c Zr _d Ti _1-a-b-c-d O ₃ , provided that 0 ≦ x ≦ 0. 10, 0 ≦ y ≦ 0.10, 0 <x + y, 0 ≦ a ≦ 0.08, 0 ≦ b ≦ 0.04, 0 ≦ c ≦ 0.01,0. A sintered body made of a perovskite compound represented by 015 <a + b, 0.43 ≦ d ≦ 0.55, wherein the perovskite compound has an average crystal particle size of 0.6 to 7 μm and the sintered material A piezoelectric ceramic composition characterized in that a four-point bending strength of a body is 70 MPa or more and a fracture toughness value is 0.7 MPam ^1/2 or more. It juxtaposed a plurality of partition walls at least partially formed of a piezoelectric ceramic composition, between the partition wall and the flow path member comprising a flow path of ink, and driving electrodes formed on both sides of the partition, the upper Symbol It is bonded to the top surface of the partition wall, and a cover plate covering the channel, in the ink jet recording head consisting of the respective flow paths communicating with ink discharge hole, the upper Symbol piezoelectric ceramic composition, the Al ₂ O ₃ 0. 01 to 0.06 mass%, the SiO ₂ containing 0.01 to 0.06 mass%, the balance composition formula _{Pb 1-xy Sr x Ba y} (Zn 1/3 Sb 2/3) a (Zn _1/3 Nb _2/3 ) _b (Ni _1/2 Te _1/2 ) _c Zr _d Ti _{1−a−b−c−d} O ₃ , where 0 ≦ x ≦ 0.10, 0 ≦ y ≦ 0 10, 0 <x + y, 0 ≦ a ≦ 0.08, 0 ≦ b ≦ 0.04, 0 ≦ c ≦ 0.01, 0. It consists of a perovskite type compound represented by 015 <a + b, 0.43 ≦ d ≦ 0.55, the average crystal particle diameter of the perovskite type compound is 0.6 to 7 μm, and the four-point bending strength is 70 MPa or more. An ink jet recording head formed of a sintered body having a toughness value of 0.7 MPam ^1/2 or more.

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