JP3839875B2 - Liquid discharge head, head cartridge, and liquid discharge apparatus - Google Patents

Description

【０１９３】
また、発泡液と吐出液に以下で示すような組成の液体を組み合わせて吐出させて記録を行った。その結果、従来のヘッドでは吐出が困難であった十数ｃｐ粘度の液体はもちろん１５０ｃｐという非常に高い粘度の液体でさえも良好に吐出でき、高画質な記録物を得ることができた。
【０１９４】
【外２】

【０１９５】
ところで、前述したような従来吐出されにくいとされていた液体の場合には、吐出速度が低いために、吐出方向性のバラツキが助長され記録紙上のドットの着弾精度が悪く、また吐出不安定による吐出量のバラツキが生じこれらのことで、高品位画像が得にくかった。しかし、上述の実施例の構成においては、気泡の発生を発泡液を用いることで充分に、しかも安定して行うことができる。このことで、液滴の着弾精度向上とインク吐出量の安定化を図ることができ記録画像品位を著しく向上することができた。
【０１９６】
〈可動部材の製造〉
次に、本発明の最も大きな特徴である可動部材の製造工程の例について、前述の実施例で示した様々の形状の中からいくつかを選んで説明する。
【０１９７】
まず、図３に示した可動部材３１の製法の一例について図２９（ａ）〜（ｃ）を用いて説明する。
【０１９８】
（ａ）ＳＵＳ基板１１００上に厚さ０．５μｍのレジスト１１０１をパターニングする。パターニングするレジスト１１０１の幅は、スリットとして残す幅を３μｍとしたとき、０．５μｍ厚のレジストの場合、１２μｍとする。
【０１９９】
（ｂ）ＳＵＳ基板１１００に対して電気メッキを行ってＳＵＳ基板１１００上にニッケル層１１０２を５μｍ成長させる。メッキ液としては、スルフォミン酸ニッケルに応力減少剤（ワールドメタル社製：ゼオロール）と、ほう酸、ピット防止剤（ワールドメタル社製：ＮＰ−ＡＰＳ）、塩化ニッケルを使用した。電着時の電界のかけ方としては、アノード側に電極を付け、カソード側に既にレジスト１１０１をパターニングしたＳＵＳ基板１１００を取り付け、メッキ液の温度を５０℃とし、電流密度を５Ａ／ｃｍ² とした。
【０２００】
この条件下でニッケル層１１０２を成長させると、ニッケル層１１０２は、０．５μｍ成長した時点から厚さ方向以外にレジスト１１０１を覆う方向にも成長する。そして、総厚が５μｍとなったときには、ニッケル層１１０２はレジスト１１０１の両側方をそれぞれ約４．５μｍ覆う。その結果、レジスト１１０１上では３μｍ幅の隙間がレジスト１１０１のパターンに沿って形成され、この隙間の部分でのニッケル層１１０２の厚み方向での曲率半径は４．５μｍとなる。
【０２０１】
（ｃ）メッキを終了したＳＵＳ基板１１００に超音波振動を与え、ニッケル層１１０２の部分をＳＵＳＵ基板１１００から剥離し、図示上方に向かって幅が徐々に狭くなっていく形状の可動部材３１を得る。
【０２０２】
ここで、可動部材３１の図示下面にはレジスト１１０１の跡である段差が生じているが、この段差の高さは０．５μｍであるので、可動部材３１の図示下面は実質的に平面である。
【０２０３】
次に、図１７（ｃ）に示した可動部材３１の製法の一例について図３０（ａ）〜（ｅ）を用いて説明する。
【０２０４】
（ａ）ＳＵＳ基板１１００上に厚さ２．５μｍのレジスト１１０１ａをパターニングする。パターニングするレジスト１１０１ａの幅は、スリットとして残す幅に合わせる。
【０２０５】
（ｂ）ＳＵＳ基板１１００に対して電気メッキを行ってＳＵＳ基板１１００上にニッケル層１１０２ａを２．５μｍ成長させる。メッキ液としては、スルフォミン酸ニッケルに応力減少剤（ワールドメタル社製：ゼオロール）と、ほう酸、ピット防止剤（ワールドメタル社製：ＮＰ−ＡＰＳ）、塩化ニッケルを使用した。電着時の電界のかけ方としては、アノード側に電極を付け、カソード側に既にレジスト１１０１ａ，１１０１ｂをパターニングしたＳＵＳ基板１１００を取り付け、メッキ液の温度を５０℃とし、電流密度を５Ａ／ｃｍ² とした。
【０２０６】
（ｃ）上述したレジスト１１０１ａに重ねて、再び厚さ２．５μｍのレジスト１１０１ｂをパターニングする。このレジスト１１０ｂの幅は、初めにパターニングしたレジスト１１０１ａの幅よりも大きいものとする。
【０２０７】
（ｄ）上述のニッケル層１１０２ａに対して再び電気メッキを行い、２層目のニッケル層１１０２ｂを２．５μｍ成長させる。メッキの条件は、１層目のニッケル層１１０２ａを形成したときと同じである。
【０２０８】
（ｅ）レジスト１１０１ａ，１１０１ｂを除去した後、ＳＵＳ基板１１００に超音波振動を与え、１層目のニッケル層１１０２ａの部分をＳＵＳ基板１１００から剥離し、２段形状の可動部材３１を得る。
【０２０９】
次に、図１７（ｄ）に示した可動部材３１の製法の一例について図３１（ａ）〜（ｃ）を用いて説明する。
【０２１０】
（ａ）ＳＵＳ基板１１００上に厚さ１５μｍのレジスト１１０１をパターニングする。この際、パターニング後のレジスト１１０１の側面に傾斜がつくように、露光時の焦点をずらす。
【０２１１】
（ｂ）ＳＵＳ基板１１００に対して電気メッキを行ってＳＵＳ基板１１００上にニッケル層１１０２を５μｍ成長させる。メッキ液としては、スルフォミン酸ニッケルに応力減少剤（ワールドメタル社製：ゼオロール）と、ほう酸、ピット防止剤（ワールドメタル社製：ＮＰ−ＡＰＳ）、塩化ニッケルを使用した。電着時の電界のかけ方としては、アノード側に電極を付け、カソード側に既にレジスト１１０１をパターニングしたＳＵＳ基板１１００を取り付け、メッキ液の温度を５０℃とし、電流密度を５Ａ／ｃｍ² とした。
【０２１２】
（ｃ）上記のようなメッキを終了したＳＵＳ基板１１００に超音波振動を与え、ニッケル層１１０２の部分をＳＵＳ基板１１００から剥離する。これを上下反転すると、台形状の可動部材３１が得られる。
【０２１３】
次に、図１７（ｈ）に示した可動部材３１の製法の一例について図３２（ａ）〜（ｃ）を用いて説明する。
【０２１４】
（ａ）ＳＵＳ基板１１００上にレジスト１１０１ａをパターニングする。
【０２１５】
（ｂ）レジスト１１０１をパターニングしたＳＵＳ基板１１００をエッチング液（塩化第２鉄または塩化第２銅の水溶液）に浸漬し、レジスト１１０１ａから露出している部分を５μｍエッチングする。その後、レジスト１１０１ａを剥離する。
【０２１６】
（ｃ）ＳＵＳ基板１１００のエッチングされた面全体に、再びレジスト１１０１ｂを塗布する。
【０２１７】
（ｄ）上記工程で塗布したレジスト１１０１ｂを、ＳＵＳ基板１１００のエッチングされた部位の底部のみにレジスト１１０ｂが残るように、露光によりパターニングする。
【０２１８】
（ｅ）上述のようにしたＳＵＳ基板１１００を母材として、ＳＵＳ基板１１００に対して電気メッキを行ってＳＵＳ基板１１００上にニッケル層１１０２を５μｍ成長させる。メッキ液としては、スルフォミン酸ニッケルに応力減少剤（ワールドメタル社製：ゼオロール）と、ほう酸、ピット防止剤（ワールドメタル社製：ＮＰ−ＡＰＳ）、塩化ニッケルを使用した。電着時の電界のかけ方としては、アノード側に電極を付け、カソード側に既にレジスト１１０１ｂをパターニングしたＳＵＳ基板１１００を取り付け、メッキ液の温度を５０℃とし、電流密度を５Ａ／ｃｍ² とした。
【０２１９】
（ｆ）上記のようなメッキを終了したＳＵＳ基板１１００に超音波振動を与え、ニッケル層１１０２の部分をＳＵＳ基板１１００から剥離し、幅方向の両端に立面部が一体的に設けられた可動部材３１が得られる。
【０２２０】
＜液体吐出ヘッドの製造＞
次に、本発明の液体吐出ヘッドの製造工程について説明する。
【０２２１】
図２で示したような液体吐出ヘッドの場合には、素子基板１上に可動部材３１を設けるための土台３４をドライフィルム等をパターニングすることで形成し、この土台３４に、例えば前述のようにして形成した可動部材３１を接着、もしくは溶着固定した。その後、各液流路１０を構成する複数の溝と吐出口１８と共通液室１３を構成する凹部を有する溝付き部材を、溝と可動部材３１が対応するような状態で素子基板１に接合することで形成した。
【０２２２】
次に、図１４や図２８で示されるような２流路構成の液体吐出ヘッドの製造工程について説明する。
【０２２３】
大まかには、素子基板１上に第２液流路１６の壁を形成し、その上に、可動部材３１を有する分離壁３０を取り付け、さらにその上に第１液流路１４を構成する溝等が設けられた溝付き部材５０を取り付ける。もしくは、第２液流路１６の壁を形成した後、この壁の上に分離壁３０を取り付けた溝付き部材５０を接合することでヘッドの製造を行った。
【０２２４】
さらに第２液流路１６の作製方法について詳しく説明する。
【０２２５】
図３３（ａ）〜（ｅ）は、本発明の液体吐出ヘッドの製造方法の一例を説明するための概略断面図である。
【０２２６】
本例においては、（ａ）に示すように、素子基板（シリコンウエハ）１上に半導体製造工程で用いるのと同様の製造装置を用いてハフニュウムボライドやチッ化タンタル等からなる発熱体２を有する電気熱変換用素子を形成した後、次工程における感光性樹脂との密着性の向上を目的として素子基板１の表面に洗浄を施した。さらに、密着性を向上させるには、素子基板１の表面に紫外線−オゾン等による表面改質を行った後、例えばシランカップリング剤（日本ユニカ製：Ａ１８９）をエチルアルコールで１重量％に希釈した液を上記改質表面上にスピンコートすることで達成される。
【０２２７】
次に、表面洗浄を行い、密着性を向上した素子基板１上に、（ｂ）に示すように、紫外線感光性樹脂フィルム（東京応化製：ドライフィルム オーディルＳＹ−３１８）ＤＦをラミネートした。
【０２２８】
次に、（ｃ）に示すように、ドライフィルムＤＦ上にフォトマスクＰＭを配し、このフォトマスクＰＭを介してドライフィルムＤＦのうち、第２流路壁として残す部分に紫外線を照射した。この露光工程は、キヤノン（株）製：ＭＰＡ−６００を用いて行い、約６００ｍＪ／ｃｍ²の露光量で行った。
【０２２９】
次に、（ｄ）に示すように、ドライフィルムＤＦを、キシレンとブチルセルソルブアセテートとの混合液からなる現像液（東京応化製：ＢＭＲＣ−３）で現像し、未露光部分を溶解させ、露光して硬化した部分を第２液流路１６の壁部分として形成した。さらに、素子基板１表面に残った残渣を酸素プラズマアッシング装置（アルカンテック社製：ＭＡＳ−８００）で約９０秒間処理して取り除き、引き続き、１５０℃で２時間、さらに紫外線照射１００ｍＪ／ｃｍ²を行って露光部分を完全に硬化させた。
【０２３０】
以上の方法により、上記シリコン基板から分割、作製される複数のヒータボード（素子基板）に対し、一様に第２液流路１６を精度よく形成することができる。シリコン基板を、厚さ０．０５ｍｍのダイヤモンドブレードを取り付けたダイシングマシン（東京精密製：ＡＷＤ−４０００）で各々のヒータボード１に切断、分離した。分離されたヒータボード１を接着剤（東レ製：ＳＥ４４００）でアルミベースプレート（支持体）７０上に固定した（図３６）。次いで、予めアルミベースプレート７０上に接合しておいたプリント配線基板７３（図３６）と、ヒータボード１とを直径０．０５ｍｍのアルミワイヤ（図示略）で接続した。
【０２３１】
次に、このようにして得られたヒータボード１に、図３３（ｅ）に示すように、上述の方法で溝付き部材５０と分離壁３０との接合体を位置決め接合した。すなわち、分離壁３０を有する溝付き部材５０とヒータボード１とを位置決めし、押さえバネ７８（図３６）により係合、固定した後、インク・発泡液用供給部材８０（図３６）をアルミベースプレート７０上に接合固定し、アルミワイヤ間、溝付き部材５０とヒータボード１とインク・発泡液用供給部材８０との隙間をシリコーンシーラント（東芝シリコーン製：ＴＳＥ３９９）で封止して完成させた。
【０２３２】
以上の製法で第２液流路１６を形成することにより、各ヒータボード１の各発熱体２に対して位置ズレのない精度の良い流路を得ることができる。特に、溝付き部材５０と分離壁３０とをあらかじめ先の工程で接合しておくことで、第１液流路１４と可動部材３１の位置精度を高めることができる。
【０２３３】
そして、これらの高精度製造技術によって、吐出安定化が図られ印字品位が向上する。また、ウエハ上に一括で形成することが可能なため、多量に低コストで製造することが可能である。
【０２３４】
なお、本例では、第２液流路１６を形成するために紫外線硬化型のドライフィルムを用いたが、紫外域、特に２４８ｎｍ付近に吸収帯域をもつ樹脂を用い、ラミネート後、硬化させ、エキシマレーザで第２液流路１６となる部分の樹脂を直接除去することによっても得ることが可能である。
【０２３５】
図３４（ａ）〜（ｄ）は、本発明の液体吐出ヘッドの製造方法の他の例を説明するための概略断面図である。
【０２３６】
本例においては、（ａ）に示すように、ＳＵＳ基板１１００上に厚さ１５μｍのレジスト１０１を第２液流路の形状でパターニングした。
【０２３７】
次に、（ｂ）に示すように、ＳＵＳ基板１１００に対して電気メッキを行ってＳＵＳ基板１１００上にニッケル層１１０２を同じく１５μｍ成長させた。メッキ液としては、スルフォミン酸ニッケルに応力減少剤（ワールドメタル社製：ゼロオール）とほう酸、ピット防止剤（ワールドメタル社製：ＮＰ−ＡＰＳ）、塩化ニッケルを使用した。電着時の電界のかけ方としては、アノード側に電極を付け、カソード側に既にパターニングしたＳＵＳ基板１１００を取り付け、メッキ液の温度を５０℃とし、電流密度を５Ａ／ｃｍ²とした。
【０２３８】
次に、（ｃ）に示すように、上記のようなメッキを終了したＳＵＳ基板１１００に超音波振動を与え、ニッケル層１１０２の部分をＳＵＳ基板１１００から剥離し、所望の第２の液流路を得た。
【０２３９】
一方、電気熱変換用素子を配設したヒータボードを、半導体と同様の製造装置を用いてシリコンウエハに形成した。このウエハを先の実施例と同様に、ダイシングマシンで各々のヒータボードに分離した。このヒータボード１を、予めプリント配線基板７３が接合されたアルミベースプレート７０に接合し、プリント配線基板７３とアルミワイヤ（図示略）とを接続することで電気的配線を形成した。このような状態のヒータボード１上に、図３４（ｄ）に示すように、先の工程で得た第２液流路１６を位置決め固定した。この固定に際しては、後工程で、図３３を用いて説明した例と同様に分離壁を固定した溝付き部材と押さえバネによって係合・密着されるため、溝付き部材接合時に位置ズレが発生しない程度に固定されていれば十分である。
【０２４０】
本例では、上記位置決め固定に紫外線硬化型接着剤（グレースジャパン製：アミコンＵＶ−３００）を塗布し、紫外線照射装置を用い、露光量を１００ｍＪ／ｃｍ²として約３秒間で固定を完了した。
【０２４１】
本例の製法によれば、発熱体２に対して位置ズレのない精度の高い第２液流路１６を得ることができることに加え、ニッケルで流路壁を形成しているため、アルカリ性の液体に強く、信頼性の高いヘッドを提供することが可能となる。
【０２４２】
図３５（ａ）〜（ｄ）は、本発明の液体吐出ヘッドの製造方法のさらに他の例を説明するための概略断面図である。
【０２４３】
本例においては、（ａ）に示すように、アライメント穴１１００ａあるいはマークを有する厚さ１５μｍのＳＵＳ基板１１００の両面にレジスト１１０３を塗布した。ここで、レジスト１１０３としては、東京応化製のＰＭＥＲＰ−ＡＲ９００を使用した。
【０２４４】
この後、（ｂ）に示すように、ＳＵＳ基板１１００のアライメント穴１１００ａに合わせて、露光装置（キヤノン（株）製：ＭＰＡ−６００）を用いて露光し、第２液流路を形成すべき部分のレジスト１１０３を除去した。露光は８００ｍＪ／ｃｍ²の露光量で行った。
【０２４５】
次に、（ｃ）に示すように、両面のレジスト１１０３がパターニングされたＳＵＳ基板１１００を、エッチング液（塩化第２鉄または塩化第２銅の水溶液）に浸漬し、レジスト１１０３から露出している部分をエッチングした後、レジスト１１０３を剥離した。
【０２４６】
次に、（ｄ）に示すように、先の製造方法の例と同様に、ヒータボード１上に、エッチングされたＳＵＳ基板１１００を位置決め固定して第２液流路１６を有する液体吐出ヘッドを組み立てた。
【０２４７】
本例の製法によれば、発熱体２に対し位置ズレのない精度の高い第２液流路１６を得ることができることに加え、ＳＵＳで流路を形成しているため、酸やアルカリ性の液体に強く信頼性の高い液体吐出ヘッドを提供することができる。
【０２４８】
以上説明したように、本例の製造方法によれば、素子基板状に予め第２液流路の壁を配設することによって、発熱体と第２液流路とが高精度に位置決めすることが可能となる。また、切断、分離前の基板上の多数の素子基板に対して第２液流路を同時に形成することができるので、多量に、かつ、低コストの液体吐出ヘッドを提供することができる。
【０２４９】
また、本例の製造方法によって得られた液体吐出ヘッドは、発熱体と第２液流路とが高精度に位置決めされているので、電気熱変換体の発熱による発泡の圧力を効率よく受けることができ、吐出効率に優れたものとなる。
【０２５０】
＜液体吐出ヘッドカートリッジ＞
次に、上記実施形態例に係る液体吐出ヘッドを搭載した液体吐出ヘッドカートリッジを概略説明する。
【０２５１】
図３６は、前述した液体吐出ヘッドを含む液体吐出ヘッドカートリッジの模式的分解斜視図であり、液体吐出ヘッドカートリッジは、主に液体吐出ヘッド部２００と液体容器９０とから概略構成されている。
【０２５２】
液体吐出ヘッド部２００は、素子基板１、分離壁３０、溝付き部材５０、押さえバネ７８、液体供給部材８０、アルミベースプレート（支持体）７０等から成っている。素子基板１には、前述のように発泡液に熱を与えるための発熱抵抗体が、複数個、列状に設けられており、また、この発熱抵抗体を選択的に駆動するための機能素子が複数設けられている。この素子基板１と可動壁を持つ前述の分離壁３０との間に発泡液路が形成され発泡液が流通する。この分離壁３０と溝付き部材５０との接合によって、吐出される吐出液体が流通する吐出流路（不図示）が形成される。
【０２５３】
押さえバネ７８は、溝付き部材５０に素子基板１方向への付勢力を作用させる部材であり、この付勢力により素子基板１、分離壁３０、溝付き部材５０と、後述する支持体７０とを良好に一体化させている。
【０２５４】
支持体７０は、素子基板１等を支持するためのものであり、この支持体７０上にはさらに素子基板１に接続し電気信号を供給するためのプリント配線基板７３や、装置側と接続することで装置側と電気信号のやりとりを行うためのコンタクトパッド７４が配置されている。
【０２５５】
液体容器９０は、液体吐出ヘッド部２００に供給される、インク等の吐出液体と気泡を発生させるための発泡液とを内部に区分収容している。液体容器９０の外側には、液体吐出ヘッド部２００と液体容器９０との接続を行う接続部材を配置するための位置決め部９４と、接続部材を固定するための固定軸９５が設けられている。吐出液体の供給は、液体容器９０の吐出液体供給路９２から接続部材の供給路８４を介して液体供給部材８０の吐出液体供給路８１に供給され、各部材の液供給路８３，７９，２０を介して第１の共通液室に供給される。発泡液も同様に、液体容器９０の発泡液体供給路９３から接続部材の供給路を介して液体供給部材８０の発泡液供給路８２に供給され、各部材の液供給路８４，７９，２１を介して第２液室に供給される。
【０２５６】
以上の液体吐出ヘッドカートリッジにおいては、発泡液と吐出液が異なる液体である場合も、供給を行いうる供給形態および液体容器９０で説明したが、吐出液体と発泡液体とが同じである場合には、発泡液と吐出液の供給経路および容器を分けなくてもよい。
【０２５７】
なお、この液体容器９０には、各液体の消費後に液体を再充填して使用してもよい。このためには液体容器９０に液体注入口を設けておくことが望ましい。又、液体吐出ヘッド部２００と液体容器９０とは一体であってもよく、分離可能としてもよい。
【０２５８】
＜液体吐出装置＞
図３７は、前述の液体吐出ヘッドを搭載した液体吐出装置の概略構成を示している。本実施例では特に吐出液体としてインクを用いたインク吐出記録装置ＩＪＲＡを用いて説明する。液体吐出装置のキャリッジＨＣは、インクを収容する液体容器９０と液体吐出ヘッド部２００とが着脱可能なヘッドカートリッジを搭載しており、被記録媒体搬送手段で搬送される記録紙等の被記録媒体１５０の幅方向（矢印ａ，ｂ方向）に往復移動する。
【０２５９】
不図示の駆動信号供給手段からキャリッジＨＣ上の液体吐出手段に駆動信号が供給されると、この信号に応じて液体吐出ヘッド部２００から被記録媒体１５０に対して記録液体が吐出される。
【０２６０】
また、本実施例の液体吐出装置においては、被記録媒体搬送手段とキャリッジＨＣを駆動するための駆動源としてのモータ１１１、駆動源からの動力をキャリッジＨＣに伝えるためのギア１１２，１１３、及びキャリッジ軸８５等を有している。この記録装置及びこの記録装置で行う液体吐出方法によって、各種の被記録媒体に対して液体を吐出することで良好な画像の記録物を得ることができた。
【０２６１】
図３８は、本発明の液体吐出ヘッドを適用したインク吐出記録装置を動作させるための装置全体のブロック図である。
【０２６２】
記録装置は、ホストコンピュータ３００より印字情報を制御信号として受ける。印字情報は印字装置内部の入出力インタフェイス３０１に一時保存されると同時に、記録装置内で処理可能なデータに変換され、ヘッド駆動信号供給手段を兼ねるＣＰＵ３０２に入力される。ＣＰＵ３０２はＲＯＭ３０３に保存されている制御プログラムに基づき、前記ＣＰＵ３０２に入力されたデータをＲＡＭ３０４等の周辺ユニットを用いて処理し、印字するデータ（画像データ）に変換する。
【０２６３】
またＣＰＵ３０２は前記画像データを記録用紙上の適当な位置に記録するために、画像データに同期して記録用紙およびヘッド２００を移動する駆動用モータ３０６を駆動するための駆動データを作る。画像データおよびモータ駆動データは、各々ヘッドドライバ３０７と、モータドライバ３０５を介し、ヘッド２００および駆動モータ３０６に伝達され、それぞれ制御されたタイミングで駆動され画像を形成する。
【０２６４】
上述のような記録装置に適用でき、インク等の液体の付与が行われる被記録媒体としては、各種の紙やＯＨＰシート、コンパクトディスクや装飾板等に用いられるプラスチック材、布帛、アルミニュウムや銅等の金属材、牛皮、豚皮、人工皮革等の皮革材、木、合板等の木材、竹材、タイル等のセラミックス材、スポンジ等の三次元構造体等を対象とすることができる。
【０２６５】
また上述の記録装置として、各種の紙やＯＨＰシート等に対して記録を行うプリンタ装置、コンパクトディスク等のプラスチック材に記録を行うプラスチック用記録装置、金属板に記録を行う金属用記録装置、皮革に記録を行う皮革用記録装置、木材に記録を行う木材用記録装置、セラミックス材に記録を行うセラミックス用記録装置、スポンジ等の三次元網状構造体に対して記録を行う記録装置、又布帛に記録を行う捺染装置等をも含むものである。
【０２６６】
またこれらの液体吐出装置に用いる吐出液としては、夫々の被記録媒体や記録条件に合わせた液体を用いればよい。
【０２６７】
＜記録システム＞
次に、本発明の液体吐出ヘッドを記録ヘッドとして用い被記録媒体に対して記録を行う、インクジェット記録システムの一例を説明する。
【０２６８】
図３９は、前述した本発明の液体吐出ヘッドを用いたインクジェット記録システムの構成を説明するための模式図である。本実施例における液体吐出ヘッドは、被記録媒体１５０の記録可能幅に対応した長さに３６０ｄｐｉの間隔で吐出口を複数配したフルライン型のヘッドであり、イエロー（Ｙ），マゼンタ（Ｍ），シアン（Ｃ），ブラック（Ｂｋ）の４色に対応した４つのヘッド２０１ａ〜２０１ｄをホルダ２０２によりＸ方向に所定の間隔を持って互いに平行に固定支持されている。
【０２６９】
これらのヘッド２０１ａ〜２０１ｄに対してそれぞれ駆動信号供給手段を構成するヘッドドライバ３０７から信号が供給され、この信号に基づいて各ヘッド２０１ａ〜２０１ｄの駆動が成される。
【０２７０】
各ヘッド２０１ａ〜２０１ｄには、吐出液としてＹ，Ｍ，Ｃ，Ｂｋの４色のインクがそれぞれインク容器２０４ａ〜２０４ｄから供給されている。なお、符号２０４ｅは発泡液が蓄えられた発泡液容器であり、この発泡液容器２０４ｅから各ヘッド２０１ａ〜２０１ｄに発泡液が供給される構成になっている。
【０２７１】
また、各ヘッド２０１ａ〜２０１ｄの下方には、内部にスポンジ等のインク吸収部材が配されたヘッドキャップ２０３ａ〜２０３ｄが設けられており、非記録時に各ヘッド２０１ａ〜２０１ｄの吐出口を覆うことでヘッド２０１ａ〜２０１ｄの保守を成すことができる。
【０２７２】
符号２０６は、先の各実施例で説明したような各種、非記録媒体を搬送するための搬送手段を構成する搬送ベルトである。搬送ベルト２０６は、各種ローラにより所定の経路に引き回されており、モータドライバ３０５に接続された駆動用ローラにより駆動される。
【０２７３】
本実施例のインクジェット記録システムにおいては、記録を行う前後に被記録媒体に対して各種の処理を行う前処理装置２５１および後処理装置２５２をそれぞれ被記録媒体搬送経路の上流と下流に設けている。
【０２７４】
前処理と後処理は、記録を行う被記録媒体の種類やインクの種類に応じて、その処理内容が異なるが、例えば、金属、プラスチック、セラミックス等の被記録媒体に対しては、前処理として、紫外線とオゾンの照射を行い、その表面を活性化することでインクの付着性の向上を図ることができる。また、プラスチック等の静電気を生じやすい被記録媒体においては、静電気によってその表面にゴミが付着しやすく、このゴミによって良好な記録が妨げられる場合がある。このため、前処理としてイオナイザ装置を用い被記録媒体の静電気を除去することで、被記録媒体からごみの除去を行うとよい。また、被記録媒体として布帛を用いる場合には、滲み防止、染着率の向上等の観点から布帛にアルカリ性物質、水溶性物質、合成高分子、水溶性金属塩、尿素およびチオ尿素から選択される物質を付与する処理を前処理として行えばよい。前処理としては、これらに限らず、被記録媒体の温度を記録に適切な温度にする処理等であってもよい。
【０２７５】
一方、後処理は、インクが付与された被記録媒体に対して熱処理、紫外線照射等によるインクの定着を促進する定着処理や、前処理で付与し未反応で残った処理剤を洗浄する処理等を行うものである。
【０２７６】
なお、本実施例では、ヘッド２０１ａ〜２０１ｄとしてフルラインヘッドを用いて説明したが、これに限らず、前述したような小型のヘッドを被記録媒体の幅方向に搬送して記録を行う形態のものであってもよい。
【０２７７】
＜ヘッドキット＞
以下に、本発明の液体吐出ヘッドを有するヘッドキットを説明する。図４０は、このようなヘッドキットを示した模式図である。このヘッドキット５００は、インクを吐出するインク吐出部５１１を有する本発明のヘッド５１０と、このヘッド５１０と不可分もしくは分離可能な液体容器であるインク容器５２０と、このインク容器５２０にインクを充填するためのインクを保持したインク充填手段５３０とを、キット容器５０１内に納めたものである。
【０２７８】
インクを消費し終わった場合には、インク容器５２０の大気連通口５２１やヘッド５１０との接続部や、もしくはインク容器５２０の壁に開けた穴などに、インク充填手段５３０の挿入部（注射針等）５３１の一部を挿入し、この挿入部５３１を介してインク充填手段５３０内のインクをインク容器５２０内に充填すればよい。
【０２７９】
このように、本発明のヘッド５１０と、インク容器５２０やインク充填手段５３０等を一つのキット容器５０１内に納めてキットにすることで、インクが消費されてしまっても前述のようにすぐに、また容易にインクをインク容器５２０内に充填することができ、記録の開始を迅速に行うことができる。
【０２８０】
なお、本実施例のヘッドキット５００では、インク充填手段５３０が含まれるもので説明を行ったが、ヘッドキットとしては、インク充填手段を持たず、インクが充填された分離可能タイプのインク容器とヘッドとがキット容器５１０内に納められている形態のものであってもよい。
【０２８１】
また、この図４０では、インク容器５２０に対してインクを充填するインク充填手段５３０のみを示しているが、インク容器５２０の他に発泡液を発泡液容器に充填するための発泡液充填手段をキット容器内に納めた形態のものであってもよい。
【０２８２】
本発明は、上述したような発熱体の面に沿う方向に設けられた液流路の一端に吐出口を有する、いわゆるエッジシュータタイプの液体吐出ヘッドに限定されることなく、例えば図４１に示すような発熱体２の面に対向する位置に吐出口１８を有する、いわゆるサイドシュータタイプの液体吐出ヘッドにも適用可能である。
【０２８３】
図４１に示したサイドシュータタイプの液体吐出ヘッドは、各吐出口１８ごとに、液体に気泡を発生させるための熱エネルギーを与える発熱体２が設けられた素子基板１上に、発泡液用の第２液流路１６が形成され、その上に溝付き部材５０に設けられた吐出口１８に直接連通した吐出液用の第１液流路１４が形成され、第１液流路１４と第２液流路１６とは、金属等の弾性を有する材料で構成された分離壁３０により区分されている点で、上述のエッジシュータタイプの液体吐出ヘッドと同様である。
【０２８４】
サイドシュータタイプの液体吐出ヘッドは、上記第１液流路１４上に配された溝付き部材（オリフィスプレート）５０のうち、発熱体２の直上の部分に吐出口１８が設けられている点に特徴がある。この吐出口１８と発熱体２との間の分離壁３０には、観音開きに開口しそれぞれ発熱体２と対向する面からその反対側の面に向かって幅が小さくなっている一対の可動部材３１が設けられている。両可動部材３１は支点３３で支持される片持梁形状のもので、両方の自由端３２同士は、非吐出時においては、吐出口１８の中央部分の直下に位置するスリット３５によりわずかに離間して対向している。吐出時においては、両可動部材３１は、図４１中の矢印で示すように、気泡発生領域１１における発泡液の発泡によって第１液流路１４側に開口し、発泡液の収縮によって閉口する。この領域Ｃには、吐出液を貯留する吐出液タンク（不図示）から吐出液がリフィルされて吐出可能状態となり、次の発泡液の発泡に備えることができる。
【０２８５】
第１液流路１４は、他の吐出口１８の第１液流路１４とともに、第１共通液室１５を介して吐出液タンクに連絡しており、第２液流路１６も、他の吐出口１８の第２液流路１６とともに、第２共通液室１７を介して、発泡液を貯留する発泡液タンク（不図示）に連絡している。
【０２８６】
このような構成を有するサイドシュータタイプの液体吐出ヘッドにおいても、エッジシュータタイプの液体吐出ヘッドとほぼ同様に、吐出液のリフィルを向上させつつ、高吐出効率、高吐出圧で液体を吐出することができるという優れた効果を得ることができる。
【０２８７】
また、製造方法については、溝付き部材５０に設けられる吐出口１８の位置が異なることと共通液室１５，１７の位置及び構造が異なること以外は、エッジシュータタイプの液体吐出ヘッドと実質的に同じである。すなわち、可動部材３１を有する分離壁３０と第２液流路１６を構成する流路壁との関係は両者とも同じである。
【０２８８】
さらに、上述した各実施例では、可動部材の形状によって、変位する際の液体に対する抵抗を小さくした例を示したが、発熱体と対向する面と反対側の面の液体の接触角を、発熱体と対向する面のそれよりも小さくするような処理を可動部材に行うことでも、変位する際の液体に対する抵抗を小さくすることもできる。
【０２８９】
【発明の効果】
上述したような、定常状態の第１の位置から変位後の位置である第２の位置へ変位するときの流路内の液体に対する抵抗を小さくした可動部材を用い、気泡の発生に基づく圧力により可動部材を変位させて液体を吐出口側に導く本発明の液体吐出ヘッドによると、可動部材が変位し易くなり、吐出効率及び吐出力をより向上することができる。さらに、可動部材の発熱体との対向面を平面としたり、あるいは幅方向の両端部を中央部よりも発熱体側に突出させた形状とすることで、可動部材は気泡の圧力成分を受けやすく、あるいは逃し難くなり、気泡の発生に基づく圧力をより効果的に可動部材の変位に利用することができる。
【０２９０】
また、本発明の特徴的な構成によれば、低温や低湿で長期放置を行った場合であっても不吐出になることを防止でき、仮に不吐出になっても予備吐出や吸引回復といった回復処理をわずかに行うだけで正常状態に即座に復帰できる利点もある。これに伴い、回復時間の短縮や回復による液体の損失を低減でき、ランニングコストも大幅に下げることが可能である。
【０２９１】
また、特に本発明のリフィル特性を向上した構成によれば、連続吐出時の応答性、気泡の安定成長、液滴の安定化を達成して、高速液体吐出による高速記録また高画質記録を可能にすることができた。
【０２９２】
また、２流路構成のヘッドにおいて発泡液として、発泡しやすい液体や、発熱体上への堆積物（こげ等）が生じにくい液体を用いることで、吐出液の選択の自由度が高くなり、発泡が生じにくい高粘性液体、発熱体上に堆積物を生じやすい液体等、従来のバブルジェット吐出方法で吐出することが困難であった液体についても良好に吐出することができた。
【０２９３】
さらに熱に弱い液体等も、この液体に熱による悪影響を与えず吐出することができた。
【０２９４】
また、本発明の液体吐出ヘッドを記録用の液体吐出記録ヘッドとして用いることで、さらに高画質な記録を達成することができた。
【０２９５】
また、本発明の液体吐出ヘッドを用い、液体の吐出効率等がさらに向上した液体吐出装置や記録システム等を提供することができた。
【図面の簡単な説明】
【図１】本発明の液体吐出ヘッドの一例を示す模式断面図である。
【図２】図１に示した液体吐出ヘッドの部分破断斜視図である。
【図３】図１に示した液体吐出ヘッドを吐出口方向から見た模式断面図である。
【図４】従来のヘッドにおける気泡からの圧力伝搬を示す模式図である。
【図５】本発明の液体吐出ヘッドにおける気泡からの圧力伝搬を示す模式図である。
【図６】図１に示した液体吐出ヘッドの液体の流れを説明するための模式図である。
【図７】本発明の第２の実施例における液体吐出ヘッドの模式断面図である。
【図８】図７に示した液体吐出ヘッドを吐出口方向から見た模式断面図である。
【図９】本発明の第３の実施例における液体吐出ヘッドの模式断面図である。
【図１０】本発明の第４の実施例における液体吐出ヘッドの部分破断斜視図である。
【図１１】本発明の第５の実施例における液体吐出ヘッドの部分破断斜視図である。
【図１２】本発明の第６の実施例における液体吐出ヘッドの断面図である。
【図１３】本発明の第７の実施例における液体吐出ヘッドの模式断面図である。
【図１４】本発明の第８の実施例における液体吐出ヘッド（２流路）の断面図である。
【図１５】図１４に示した液体吐出ヘッドの部分破断斜視図である。
【図１６】可動部材の動作を説明するための図である。
【図１７】可動部材の種々の変形例（ａ）〜（ｉ）を示す断面図である。
【図１８】第１液流路の天井形状の他の例を説明するための図である。
【図１９】第２液流路と可動部材との配置関係を説明するための図である。
【図２０】可動部材の他の形状を説明するための図である。
【図２１】発熱体面積とインク吐出量の関係を示すグラフである。
【図２２】可動部材と発熱体との配置関係を示す図である。
【図２３】発熱体のエッジと支点までの距離と可動部材の変位量の関係を示すグラフである。
【図２４】発熱体と可動部材との配置関係を説明するための図である。
【図２５】本発明の液体吐出ヘッドの縦断面図である。
【図２６】駆動パルスの形状を示す模式図である。
【図２７】本発明の液体吐出ヘッドの供給路を説明するための断面図である。
【図２８】本発明のヘッドの分解斜視図である。
【図２９】図３に示す可動部材の製造方法を説明するための工程図である。
【図３０】図１７の（ｃ）に示す可動部材の製造方法を説明するための工程図である。
【図３１】図１７の（ｄ）に示す可動部材の製造方法を説明するための工程図である。
【図３２】図１７の（ｈ）に示す可動部材の製造方法を説明するための工程図である。
【図３３】本発明の液体吐出ヘッドの製造方法を説明するための工程図である。
【図３４】本発明の液体吐出ヘッドの製造方法を説明するための工程図である。
【図３５】本発明の液体吐出ヘッドの製造方法を説明するための工程図である。
【図３６】液体吐出ヘッドカートリッジの分解斜視図である。
【図３７】液体吐出装置の概略構成図である。
【図３８】装置ブロック図である。
【図３９】液体吐出記録システムを示す図である。
【図４０】ヘッドキットの模式図である。
【図４１】本発明を適用したサイドシュータタイプの液体吐出ヘッドの一例の断面図である。
【図４２】従来の液体吐出ヘッドの液流路構造を説明するための図である。
【符号の説明】
１ 素子基板
２ 発熱体
３ 面積中心
１０ 液流路
１１ 気泡発生領域
１２ 供給路
１３ 共通液室
１４ 第１液流路
１５ 第１共通液室
１６ 第２液流路
１７ 第２共通液室
１８ 吐出口
１９ 狭窄部
２０ 第１供給路
２１ 第２供給路
２２ 第１液流路壁
２３ 第２液流路壁
２４ 凸部
３０ 分離壁
３１ 可動部材
３１ａ 立面部
３２ 自由端
３３ 支点
３４ 支持部材
３５ スリット
３６ 気泡発生領域前壁
３７ 気泡発生領域側壁
４０ 気泡
５０ 溝付き部材
７０ 支持体
７８ 押えバネ
８０ 供給部材[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a liquid discharge head that discharges a desired liquid by generation of bubbles caused by applying thermal energy to the liquid, a head cartridge that uses the liquid discharge head, and a liquid discharge apparatus.
[0002]
In particular, the present invention relates to a liquid ejection head having a movable member that is displaced by using the generation of bubbles, a head cartridge using the liquid ejection head, and a liquid ejection apparatus.
[0003]
The present invention also relates to a printer for recording on a recording medium such as paper, thread, fiber, fabric, leather, metal, plastic, glass, wood, ceramics, a copier, a facsimile having a communication system, a word processor having a printer section, etc. And an industrial recording apparatus combined with various processing apparatuses.
[0004]
In the present invention, “recording” means not only giving an image having a meaning such as a character or a figure to a recording medium but also giving an image having no meaning such as a pattern. To do.
[0005]
[Prior art]
By applying energy such as heat to the ink, the ink undergoes a change in state accompanied by a steep volume change (bubble generation), and the ink is discharged from the discharge port by the action force based on this change in state, and this is recorded 2. Description of the Related Art An ink jet recording method for forming an image by adhering to a medium, a so-called bubble jet recording method is conventionally known. In a recording apparatus using this bubble jet recording method, as disclosed in US Pat. No. 4,723,129, etc., an ejection port for ejecting ink and an ink flow path communicating with the ejection port In general, an electrothermal converter as an energy generating means for discharging the ink disposed in the ink flow path is disposed.
[0006]
According to such a recording method, a high-quality image can be recorded at high speed and with low noise, and the ejection ports for ejecting ink can be arranged with high density in the head that performs this recording method. Therefore, it has many excellent points that a high-resolution recorded image and a color image can be easily obtained with a small apparatus. For this reason, in recent years, this bubble jet recording method has been used in many office devices such as printers, copiers, and facsimiles, and has also been used in industrial systems such as textile printing apparatuses.
[0007]
As the bubble jet technology is used in various products in this way, the following various demands have been increasing in recent years.
[0008]
For example, as a study on the demand for improvement in energy efficiency, optimization of a heating element such as adjusting the thickness of a protective film is cited. This method is effective in improving the propagation efficiency of the generated heat to the liquid.
[0009]
In addition, in order to obtain a high-quality image, a drive condition for providing a liquid discharge method capable of performing a good ink discharge based on the generation of a stable bubble with a high ink discharge speed is proposed. From the viewpoint, there has also been proposed an improved flow channel shape in order to obtain a liquid discharge head having a high filling (refill) speed of discharged liquid into the liquid flow channel.
[0010]
Of these channel shapes, the channel structure shown in FIGS. 42A and 42B is described in JP-A-63-199972. In the flow path structure and the head manufacturing method described in this publication, a back wave generated with the generation of bubbles (pressure toward the direction opposite to the direction toward the discharge port, that is, pressure toward the liquid chamber 12). It is the invention which paid attention to. This back wave is known as loss energy because it is not energy in the ejection direction.
[0011]
The invention shown in FIGS. 42A and 42B discloses the valve 5 that is located farther from the bubble generation region formed by the heat generating element 2 and located on the opposite side of the discharge port 18 with respect to the heat generating element 2. .
[0012]
In FIG. 42 (b), this valve 5 has an initial position as if attached to the ceiling of the liquid flow path 10 by a manufacturing method using a plate material or the like. It is disclosed as sagging. The present invention is disclosed as suppressing energy loss by controlling a part of the above-described back wave by the valve 5.
[0013]
However, in this configuration, as can be understood from the case where bubbles are generated inside the liquid flow path 10 that holds the liquid to be discharged, suppressing a part of the back wave by the valve 5 is difficult for liquid discharge. It turns out that it is not practical.
[0014]
Originally, the back wave itself is not directly related to ejection as described above. When this back wave is generated in the liquid flow path 10, as shown in FIG. 42 (a), the pressure directly related to the discharge among the bubbles is already in a state in which liquid can be discharged from the liquid flow path 10. Therefore, it is clear that even if a part of the back wave is suppressed, ejection is not greatly affected.
[0015]
On the other hand, in the bubble jet recording method, since heating is repeated while the heating element is in contact with the ink, deposits are generated due to scorching of ink on the surface of the heating element, but depending on the type of ink, this deposit is often generated. As a result, the generation of bubbles becomes unstable, and it may be difficult to perform good ink ejection. In addition, even when the liquid to be discharged is a liquid that is easily deteriorated by heat, or when it is difficult to obtain sufficient foaming, there has been a demand for a method for discharging well without changing the liquid to be discharged. .
[0016]
From such a point of view, a method of discharging the discharge liquid by transferring the pressure due to foaming to the discharge liquid by separating the liquid (foam liquid) that generates bubbles by heat and the liquid to be discharged (discharge liquid) into separate liquids, It is disclosed in Japanese Patent Laid-Open Nos. 61-69467, 55-81172, US Pat. No. 4,480,259, and the like. In these gazettes, the ink that is the discharge liquid and the foam liquid are completely separated by a flexible film such as silicon rubber so that the discharge liquid does not come into direct contact with the heating element, and pressure due to foaming of the foam liquid is allowed. The configuration is such that the fluid is transferred to the discharge liquid by deformation of the flexible film. With such a configuration, it is possible to prevent deposits on the surface of the heating element, improve the degree of freedom in selecting the discharge liquid, and the like.
[0017]
However, the head configured to completely separate the discharge liquid and the foaming liquid as described above is configured to transmit the pressure at the time of foaming to the discharge liquid by the expansion and contraction of the flexible film. The sexual membrane absorbs considerably. Further, since the deformation amount of the flexible film is not so large, the effect of separating the discharge liquid and the foaming liquid can be obtained, but there is a possibility that the energy efficiency and the discharge force may be reduced.
[0018]
[Problems to be solved by the invention]
The present invention basically has a fundamental discharge characteristic of a method of discharging a liquid by forming a conventional bubble (especially a bubble accompanying film boiling) in a liquid flow channel from a point of view that has not been considered in the past. The main background issue is to raise it to a level that could not be predicted in the past.
[0019]
A part of the inventors returned to the principle of droplet ejection, and conducted earnest research to provide a novel droplet ejection method using bubbles, a head used therefor, and the like, which were not obtained in the past. At this time, a first technique analysis starting from the operation of the movable member in the liquid flow path that analyzes the principle of the mechanism of the movable member in the flow path, and a second technique starting from the droplet discharge principle by the bubbles Analysis, and further, the third analysis starting from the bubble formation region of the heating element for forming bubbles was decided to be performed.
[0020]
Based on these analyses, the arrangement relationship between the fulcrum of the movable member and the free end is set so that the free end is located on the discharge port side, that is, the downstream side, and the movable member is arranged facing the heating element or the bubble generation region. This led to the establishment of a completely new technology that actively controls bubbles.
[0021]
Next, in view of the energy that the bubble itself gives to the discharge amount, the inventors have come to the knowledge that considering the growth component on the downstream side of the bubble is the largest factor that can significantly improve the discharge characteristics. That is, it has been found that efficient conversion of the growth component downstream of the bubbles in the discharge direction can improve the discharge efficiency and discharge speed. From this, the inventors have reached an extremely high technical level compared to the conventional technical level in which the growth component on the downstream side of the bubbles is positively moved to the free end side of the movable member.
[0022]
Furthermore, it is involved in the growth of a heat generation region for forming bubbles, for example, the downstream of the center line passing through the center of the area of the electrothermal transducer in the liquid flow direction, or the downstream of the bubble such as the center of the area on the surface that controls foaming. It has been found preferable to consider structural elements such as the movable member and the liquid flow path.
[0023]
On the other hand, it has been found that the refill speed can be significantly improved by considering the arrangement of the movable member and the structure of the liquid supply path.
[0024]
A part of the inventors and the present applicant have applied for the knowledge obtained in this way and the principle of liquid discharge excellent from a comprehensive viewpoint, but the present inventors presuppose this invention. I came up with a better idea.
[0025]
The point recognized by the present inventors is to achieve higher discharge efficiency and discharge power by focusing on the shape of the movable member with the aim of making more effective use of the discharge principle described above and improving it. Is a point.
[0026]
The main objects of the present invention are as follows.
The first object is to reduce the resistance received from the liquid when the movable member is displaced so that the movable member functions more effectively when the generated bubbles act on the movable member. Another object is to provide a liquid discharge head or the like that can obtain discharge force.
[0027]
In addition to the first object, the second object of the present invention can greatly reduce the heat storage in the liquid on the heating element while improving the discharge efficiency and the ejection force, and can reduce the residual bubbles on the heating element. An object of the present invention is to provide a liquid discharge head or the like that can perform good liquid discharge by reducing it.
[0028]
The third object of the present invention is to further suppress the inertia force in the direction opposite to the liquid supply direction due to the back wave and at the same time reduce the meniscus retraction amount by the valve function of the movable member. An object of the present invention is to provide a liquid discharge head or the like that improves the printing speed and the like.
[0029]
A fourth object of the present invention is to provide a liquid discharge head or the like that can reduce the deposits on the heating element, expand the application range of the discharge liquid, and have sufficiently high discharge efficiency and discharge force. There is.
[0030]
A fifth object of the present invention is to provide a liquid discharge head or the like that can increase the degree of freedom in selecting the liquid to be discharged.
[0031]
A sixth object of the present invention is to provide a head and apparatus that are easy to manufacture and inexpensive by configuring a liquid introduction path for supplying a plurality of liquids with a small number of parts, and to reduce the size of the liquid ejection. It is to provide a head, a device, and the like.
[0032]
[Means for Solving the Problems]
The typical requirements of the present invention to achieve the above object are as follows.
[0033]
A discharge port for discharging liquid;
A liquid flow path communicating with the discharge port;
A bubble generation region for generating bubbles in the liquid in the liquid flow path;
Displaced from the first position in the steady state to the second position after being displaced by the pressure based on the generation of bubbles in the bubble generation region. By this displacement, the pressure is guided to the downstream side where the discharge port is disposed, and the first pressure is generated by the negative pressure due to the contraction of bubbles. 1 A movable member that returns to the position of
The movable member has a resistance to the liquid in the flow path when the movable member is displaced from the first position to the second position, more than a resistance when the movable member returns from the second position to the first position. Small liquid discharge head.
[0034]
Or a discharge port for discharging the liquid;
A first liquid flow path communicating with the discharge port;
A second liquid flow path having a bubble generation region for generating bubbles in the liquid by applying heat to the liquid;
The first liquid is disposed between the first liquid flow path and the bubble generation region, and is a position after being displaced from the first position in a steady state by pressure based on generation of bubbles in the bubble generation region. Displacement to the second position on the liquid flow path side, and this displacement leads the pressure to the downstream side where the discharge port is arranged, and the first pressure is generated by the negative pressure due to the contraction of bubbles. 1 A movable member that returns to the position of
When the movable member is displaced from the first position to the second position, the resistance to the liquid in the first liquid flow path returns from the second position to the first position. The liquid discharge head is smaller than the resistance.
[0035]
Or a plurality of discharge ports for discharging liquid;
A plurality of grooves for configuring a plurality of first liquid flow paths that directly communicate with each discharge port;
A grooved member integrally having a concave portion constituting a first common liquid chamber for supplying a liquid to the plurality of first liquid flow paths;
An element substrate provided with a plurality of heating elements for generating bubbles in the liquid by applying heat to the liquid;
The bubble is generated between the grooved member and the element substrate and forms a part of the wall of the second liquid flow path corresponding to the heating element, and at a position facing the heating element. Is displaced from the first position in the steady state to the second position on the first liquid flow path side, which is the position after displacement, by this displacement, and the pressure is moved to the downstream side where the discharge port is disposed by this displacement. Leading to the negative pressure due to the contraction of bubbles 1 A separation wall having a movable member that returns to the position of
When the movable member is displaced from the first position to the second position, the resistance to the liquid in the first liquid flow path returns from the second position to the first position. The liquid discharge head is smaller than the resistance.
[0036]
Alternatively, a head cartridge having the above-described liquid discharge head and a liquid container that holds the liquid supplied to the liquid discharge head.
[0037]
Or the above-described liquid discharge head;
A liquid discharge apparatus comprising drive signal supply means for supplying a drive signal for discharging liquid from the liquid discharge head.
[0038]
Or the above-described liquid discharge head;
A liquid discharge apparatus comprising: a recording medium transport unit that transports a recording medium that receives the liquid ejected from the liquid ejection head.
[0039]
In the representative one of the present invention, the movable member is displaced by the action of the bubbles generated in the bubble generation region. At this time, the movable member receives the resistance of the liquid in the liquid flow path. The resistance of the liquid is reduced by making the movable member have the shape as described above. As a result, the movable member is easily displaced, and the discharge efficiency and the discharge force are further improved.
[0040]
In addition, according to the liquid discharge head of the present invention based on the extremely novel discharge principle as described above, a synergistic effect between the generated bubbles and the movable member displaced thereby can be obtained, and the liquid in the vicinity of the discharge port can be obtained. Therefore, the discharge efficiency can be improved as compared with a conventional bubble jet type liquid discharge head or the like. For example, in the most preferable embodiment of the present invention, a drastic improvement in discharge efficiency of twice or more can be achieved.
[0041]
According to a further characteristic configuration of the present invention, it is possible to prevent non-ejection even when left for a long time at a low temperature and low humidity, and even if non-ejection occurs, recovery such as preliminary ejection and suction recovery is possible. There is also an advantage that the normal state can be instantly restored with a small amount of processing.
[0042]
Specifically, even in a long-term leaving condition in which most of the conventional bubble jet type heads having 64 discharge ports do not discharge, only about half or less of the discharge ports cause defective discharge. It is. Further, when these heads are recovered by preliminary discharge, it has been necessary to perform several thousand preliminary discharges with each of the conventional heads for each discharge port. However, in the present invention, only recovery is performed with about 100 preliminary discharges. Was enough. This means that the recovery time can be shortened and the liquid loss due to the recovery can be reduced, and the running cost can be greatly reduced.
[0043]
In particular, according to the configuration with improved refill characteristics of the present invention, it is possible to achieve high-speed recording or high-quality recording by high-speed liquid ejection by achieving responsiveness during continuous ejection, stable bubble growth, and droplet stabilization. I was able to.
[0044]
Other effects of the present invention will be understood from the description of each example.
[0045]
The terms “upstream” and “downstream” used in the description of the present invention are related to the flow direction of the liquid from the liquid supply source to the discharge port through the bubble generation region (or movable member), or the direction of this configuration. It is expressed as an expression.
[0046]
The “downstream side” related to the bubble itself represents a portion of the bubble outlet side which is supposed to act directly on the droplet discharge. More specifically, it means a bubble generated in a region downstream of the center of the bubble with respect to the flow direction or the structural direction, or in a region downstream of the center of the area of the heating element.
[0047]
In addition, the term “substantially sealed” used in the description of the present invention means a state where bubbles do not pass through gaps (slits) around the movable member before the movable member is displaced when the bubbles grow. .
[0048]
Further, the “separation wall” as used in the present invention means a wall (which may include a movable member) interposed so as to separate a bubble generation region and a region directly communicating with the discharge port in a broad sense, and in a narrow sense, a bubble. This means that the flow path including the generation area is divided from the liquid flow path that directly communicates with the discharge port to prevent mixing of the liquid in each area.
[0049]
DETAILED DESCRIPTION OF THE INVENTION
Example 1
Hereinafter, a first embodiment of the present invention will be described in detail with reference to the drawings.
[0050]
First, in this embodiment, an example will be described in which the ejection force and ejection efficiency are improved by controlling the propagation direction of pressure based on bubbles and the growth direction of bubbles for ejecting liquid.
[0051]
FIG. 1 is a schematic cross-sectional view of the liquid discharge head of this embodiment cut in the liquid flow path direction, and FIG. 2 is a partially broken perspective view of the liquid discharge head. FIG. 3 is a schematic cross-sectional view of the liquid discharge head of this embodiment as viewed from the discharge port direction.
[0052]
In the liquid discharge head of this embodiment, a heating element 2 (in this embodiment, a heating resistor having a shape of 40 μm × 105 μm) that applies thermal energy to the liquid is an element substrate as a discharge energy generating element for discharging the liquid. The liquid flow path 10 is arranged on the element substrate 1 corresponding to the heating element 2. The liquid flow path 10 communicates with the discharge ports 18 and also communicates with a common liquid chamber 13 for supplying liquid to the plurality of liquid flow paths 10, and has an amount corresponding to the liquid discharged from the discharge ports 18. The liquid is received from the common liquid chamber 13.
[0053]
On the element substrate 1 of the liquid flow path 10, a flat plate-shaped movable member 31 made of an elastic material such as metal is provided in a cantilever shape so as to face the above-described heating element 2. Is provided. The movable member 31 has a substantially flat surface facing the heating element 2 and parallel to the surface of the heating element 2. Furthermore, the width of the movable member 31 gradually decreases from the surface facing the heating element 2 toward the opposite surface. One end of the movable member 31 is fixed to a base (support member) 34 formed by patterning a photosensitive resin or the like on the wall of the liquid flow path 10 or the element substrate. As a result, the movable member 31 is held and a fulcrum (fulcrum portion) 33 is formed.
[0054]
The movable member 31 has a fulcrum 33 on the upstream side of a large flow flowing from the common liquid chamber 13 to the discharge port 18 side through the movable member 31 by the liquid discharge operation, and a free end (on the downstream side of the fulcrum 33 ( A free end portion 32 is provided at a position facing the heating element 2 so as to cover the heating element 2 with a distance of about 15 μm from the heating element 2. A bubble generation region 11 is formed between the heating element 2 and the movable member 31. Note that the types, shapes, and arrangements of the heating element 2 and the movable member 31 are not limited thereto, and may be any shapes and arrangements that can control bubble growth and pressure propagation as described later.
[0055]
By causing the heating element 2 to generate heat, heat is applied to the liquid in the bubble generation region 11 between the movable member 31 and the heating element 2, and bubbles are generated in the liquid based on a film boiling phenomenon as described in US Pat. No. 4,723,129. 40 is generated. The pressure based on the generation of the bubble 40 and the bubble 40 preferentially act on the movable member 31, and the movable member 31 has the discharge port 18 around the fulcrum 33 as shown in FIG. 1B, FIG. Displaces so that it opens to the side. Depending on the displacement or the displaced state of the movable member 31, the propagation of pressure based on the generation of the bubble 40 and the growth of the bubble itself are guided to the discharge port 18 side.
[0056]
Here, one of the basic ejection principles of the present invention will be described. One of the most important principles in the present invention is that the movable member 31 disposed so as to face the bubble 40 is displaced from the first position in the steady state based on the pressure of the bubble 40 or the bubble itself. Displacement to a certain second position is to guide the pressure accompanying the generation of the bubble 40 and the bubble itself to the downstream side where the discharge port 18 is disposed by the movable member 31 that is displaced.
[0057]
This principle will be described in more detail by comparing FIG. 4 schematically showing a conventional liquid channel structure without using a movable member and FIG. 5 of the present invention. Here, the pressure propagation direction toward the discharge port is indicated as VA, and the pressure propagation direction toward the upstream side is indicated as VB.
[0058]
In the conventional head as shown in FIG. 4, there is no configuration for restricting the propagation direction of pressure by the generated bubbles 40. For this reason, the pressure propagation direction of the bubble 40 is a perpendicular direction of the bubble surface as in V1 to V8, and faces various directions. Among these, those having the component of the pressure propagation direction in the VA direction that has the greatest influence on the liquid discharge are V1 to V4, that is, the pressure propagation direction component of the portion closer to the discharge port than the almost half position of the bubble 40, This is an important part that directly contributes to discharge efficiency, discharge force, discharge speed, and the like. Furthermore, since V1 is closest to the discharge direction VA, it works efficiently. Conversely, V4 has a relatively small direction component toward VA.
[0059]
On the other hand, in the case of the present invention shown in FIG. 5, the pressure propagation directions V1 to V4 of the bubbles in which the movable member 31 faces in various directions as in the case of FIG. The pressure of the bubble 40 directly and efficiently contributes to the discharge. And the growth direction itself of the bubble 40 is also led downstream as in the pressure propagation directions V1 to V4, and grows larger downstream than upstream. As described above, by fundamentally controlling the growth direction of the bubble 40 by the movable member 31 and controlling the pressure propagation direction of the bubble 40, it is possible to achieve fundamental improvements in discharge efficiency, discharge force, discharge speed, and the like. .
[0060]
Next, returning to FIG. 1, the discharge operation of the liquid discharge head of this embodiment will be described in detail.
[0061]
FIG. 1A shows a state before energy such as electric energy is applied to the heating element 2 and before the heating element 2 generates heat. What is important here is that the movable member 31 is provided at a position facing at least the downstream portion of the bubble 40 with respect to the bubble 40 generated by the heat generation of the heating element 2. That is, at least the area center 3 of the heating element 2 (see FIG. 1B) passes through the area center 3 of the heating element 2 on the liquid flow path structure so that the downstream side of the bubble 40 acts on the movable member 31. The movable member 31 is disposed up to a position downstream of the line perpendicular to the length direction of the liquid flow path 10.
[0062]
In FIG. 1B, electric energy or the like is applied to the heating element 2 and the heating element 2 generates heat. A part of the liquid filling the bubble generation region 11 is heated by the generated heat, and the bubbles 40 accompanying the film boiling are heated. Is a state in which
[0063]
At this time, the movable member 31 is displaced from the first position to the second position by the pressure based on the generation of the bubble 40 so as to guide the propagation direction of the pressure of the bubble 40 toward the discharge port. What is important here is that, as described above, the free end 32 of the movable member 31 is disposed on the downstream side (discharge port side), and the fulcrum 33 is disposed on the upstream side (common liquid chamber 13 side). In other words, at least a part of the movable member 31 faces the downstream portion of the heating element 2, that is, the downstream portion of the bubble 40.
[0064]
FIG. 1C shows a state where the bubble 40 has further grown, but the movable member 31 is further displaced according to the pressure accompanying the generation of the bubble 40. The generated bubble 40 grows greatly from the upstream to the downstream and grows beyond the first position (dotted line position) of the movable member 31. In this way, the movable member 31 is displaced according to the growth of the bubble 40, so that the pressure propagation direction of the bubble 40 and the direction in which the volume is easily moved, that is, the growth direction of the bubble 40 toward the free end is set to the discharge port 18. It can be considered that increasing the discharge efficiency can also be directed uniformly. The movable member 31 hardly interferes with the transmission of the bubble 40 or the foaming pressure in the direction of the discharge port, and efficiently controls the pressure propagation direction and the bubble growth direction according to the magnitude of the propagating pressure. can do.
[0065]
Furthermore, since the width of the movable member 31 is gradually narrowed from the surface facing the heating element 2 toward the opposite surface as described above, the movable member 31 is displaced by the pressure based on the generation of the bubbles 40. In doing so, the movable member 31 is less susceptible to the resistance of the liquid present in the liquid flow path 10 and is displaced even at a low pressure. Therefore, the pressure component of the bubble 40 consumed for the displacement of the movable member 31 is minimal, and most of the remaining pressure component is grown in the direction of the discharge port 18.
[0066]
On the other hand, the surface of the movable member 31 that faces the heating element 2 is substantially flat, and is parallel to the surface of the heating element 2, so that it is easy to receive pressure based on the generation of bubbles 40, This is also a factor for efficiently displacing the movable member 31. In addition to this, for example, the surface of the movable member 31 facing the heating element 2 may be subjected to a surface finish, unevenness, or the structure of the movable member 31. For example, at least a portion facing the heating element 2 may be substantially concave and the side surface of the bubble 40 may be covered.
[0067]
FIG. 1D shows a state in which the bubble 40 contracts and disappears due to a decrease in the bubble internal pressure after the film boiling described above.
[0068]
The movable member 31 that has been displaced to the second position is quickly returned to the initial position (first position) in FIG. 1A due to the negative pressure due to the contraction of the bubbles 40 and the restoring force due to the spring property of the movable member itself. Return. Further, at the time of defoaming, in order to supplement the contraction volume of the bubble 40 in the bubble generation region 11 and to supplement the volume of the discharged liquid, the flow V from the upstream side (B), that is, the common liquid chamber side. _D1 , V _D2 In addition, the liquid flows from the discharge port 18 side like the flow Vc.
[0069]
The operation of the movable member 31 and the liquid discharge operation accompanying the generation of the bubbles 40 have been described above. The liquid refill in the liquid discharge head of the present invention will be described in detail below.
[0070]
The liquid supply mechanism in the present invention will be described in more detail with reference to FIG.
[0071]
After the bubble 40 enters the defoaming process after the state of the maximum volume after FIG. 1C, the volume of liquid that supplements the defoamed volume enters the bubble generation region 11 and the discharge port 18 side of the liquid flow path 10. And flows from the common liquid chamber side 13 of the supply path 12. In the conventional liquid flow path structure having no movable member 31, the amount of liquid flowing into the defoaming position from the discharge port 18 side and the amount of liquid flowing from the common liquid chamber 13 are closer to the discharge port 18 than the bubble generation region 11. This is due to the magnitude of the flow resistance between the portion and the portion close to the common liquid chamber 13. (It is based on flow path resistance and liquid inertia.)
[0072]
For this reason, when the flow resistance on the side close to the discharge port 18 is small, a large amount of liquid flows from the discharge port 18 side to the defoaming position, and the retreat amount of the meniscus M increases. In particular, as the discharge efficiency is increased by reducing the flow resistance on the side close to the discharge port 18 in order to increase the discharge efficiency, the retreat time of the meniscus M at the time of defoaming increases, and the refill time increases, resulting in high-speed printing. Was supposed to interfere.
[0073]
On the other hand, since the movable member 31 is provided in this embodiment, the bubble volume W is movable at the time of defoaming when W1 is the upper side of the first position of the movable member 31 and W2 is the bubble generation region 11 side. When the member 31 returns to the original position, the retreat of the meniscus M stops, and the liquid supply for the remaining volume of W2 is mainly performed by the liquid supply from the flow VD2 of the supply passage 12. As a result, the amount corresponding to about half of the volume of the bubble 40 has been the amount of retraction of the meniscus M, whereas the amount of retraction of the meniscus that is less than half of W1 can be suppressed. .
[0074]
Further, the liquid supply for the volume of W2 is forcibly performed mainly from the upstream side (VD2) of the supply path 12 along the surface of the movable member 31 on the side of the heating element 2 using the pressure during defoaming. Was able to achieve faster refilling.
[0075]
What is characteristic here is that when refilling using pressure at the time of defoaming was performed with a conventional head, the vibration of the meniscus increased and led to deterioration of the image quality. In this case, the movable member 31 suppresses the flow of the liquid on the discharge port 18 side with respect to the region of the liquid flow path 10 on the discharge port 18 side and the bubble generation region 11, so that the vibration of the meniscus M can be extremely reduced. It is.
[0076]
As described above, the present invention achieves high-speed refill by forced refill to the bubble generation region 11 through the supply path 12 and suppression of meniscus retreat and vibration described above, thereby enabling stable discharge and high-speed repeated discharge. When used in the recording field, image quality can be improved and high-speed recording can be realized.
[0077]
The configuration of the present invention further has the following effective functions. That is, to suppress the upstream propagation (back wave) of the pressure due to the generation of the bubble 40. Of the bubbles 40 generated on the heating element 2, most of the pressure due to the bubbles 40 on the common liquid chamber 13 side (upstream side) is a force (back wave) for pushing the liquid toward the upstream side. This back wave causes the upstream pressure, the amount of liquid movement, and the inertial force accompanying the liquid movement, which lowers the refill of the liquid into the liquid flow path 10 and hinders high-speed driving. It was. In the present invention, the refill supply performance is further improved by suppressing these actions to the upstream side by the movable member 31 first.
[0078]
Next, further characteristic structures and effects of the present embodiment will be described below.
[0079]
The supply path 12 of the present embodiment has an inner wall upstream of the heating element 2 and connected to the heating element 2 in a substantially flat manner (the surface of the heating element is not greatly depressed). In such a case, the supply of the liquid to the surface of the bubble generation region 11 and the heating element 2 is performed along the surface of the movable member 31 on the side close to the bubble generation region 11. _D2 It is done as follows. For this reason, it is suppressed that the liquid stagnates on the surface of the heating element 2, so that the deposition of the gas dissolved in the liquid and the so-called residual bubbles remaining without being defoamed can be easily removed. The heat storage is not too high. Therefore, more stable generation of bubbles can be repeated at high speed. In this embodiment, the supply path 12 having a substantially flat inner wall has been described. However, the present invention is not limited to this, and any supply path that has a gentle inner wall may be connected to the heating element surface. Any shape that does not cause stagnation of the liquid on the heating element 2 or large turbulent flow in the supply of the liquid may be used.
[0080]
Further, the liquid is supplied to the bubble generation region 11 through the side portion (slit 35) of the movable member 31. _D1 Some are done from. However, in order to more effectively guide the pressure at the time of bubble generation to the discharge port 18, a large movable member 31 is used so as to cover the entire bubble generation region 11 (cover the heating element surface) as shown in FIG. In the case where the liquid flow resistance between the bubble generation region 11 and the region near the discharge port 18 of the liquid flow path 10 is increased by returning to the first position, the above-described V _D1 The flow of the liquid from the flow toward the bubble generation region 11 is hindered. However, in the head structure of the present invention, the flow V for supplying the liquid to the bubble generation region 11 _D2 For this reason, the liquid supply performance is very high, and even if a structure that seeks to improve the discharge efficiency so as to cover the bubble generation region 11 with the movable member 31 is used, the liquid supply performance is not deteriorated.
[0081]
By the way, the position of the free end 32 and the fulcrum 33 of the movable member 31 is such that the free end 32 is relatively downstream of the fulcrum 33 as shown in FIG. Due to such a configuration, it is possible to efficiently realize functions and effects such as guiding the pressure propagation direction and growth direction of bubbles to the discharge port 18 side during the above-described foaming. Furthermore, this positional relationship achieves not only a function and an effect on ejection but also an effect that the flow resistance to the liquid flowing through the liquid flow path 10 can be reduced and refilling can be performed at high speed when supplying the liquid. As shown in FIG. 6, when the meniscus M retracted by discharge returns to the discharge port 18 by capillary force, or when liquid supply against defoaming is performed, the flow flowing in the liquid flow path 10 This is because the free end and the fulcrum 33 are arranged so as not to oppose S1, S2, and S3.
[0082]
In addition, in FIG. 1 of the present embodiment, as described above, the free end 32 of the movable member 31 has an area center 3 (an area of the heating element 2) that divides the heating element 2 into an upstream region and a downstream region. A line extending through the center (center) and perpendicular to the length direction of the liquid flow path 10) extends to the heating element 2 so as to face a position on the downstream side. As a result, the movable member 31 receives pressure or bubbles that greatly contribute to the discharge of the liquid generated downstream of the area center position 3 of the heating element 2, and the pressure and bubbles can be guided to the discharge port 18 side. Efficiency and discharge force can be improved fundamentally.
[0083]
In addition, many effects are obtained by utilizing the upstream side of the bubbles.
[0084]
Further, in the configuration of the present embodiment, the momentary mechanical displacement of the free end 32 of the movable member 31 is considered to contribute to the liquid discharge effectively.
[0085]
(Example 2)
FIG. 7 is a schematic cross-sectional view of a second embodiment of the liquid discharge head of the present invention, and FIG. 8 is a schematic cross-sectional view of the liquid discharge head shown in FIG. 7 viewed from the discharge port direction.
[0086]
In the present embodiment, the vertical surfaces 31 a extending toward the heating element 2 are integrally provided at both end portions in the width direction of the movable member 31 as in the first embodiment. The vertical surface portion 31a is located outside the bubble generation region 11 in the width direction of the movable member 31, and the side of the bubbles generated in the bubble generation region 11 is covered with the vertical surface portion 31a.
[0087]
As a result, when the movable member 31 is displaced, the resistance of the liquid existing in the liquid flow path 10 is reduced as in the first embodiment, and the escape of the foaming pressure to the side is prevented. Is used for displacement of the movable member 31 more effectively. Furthermore, since the pressure release to the direction other than the discharge port accompanying the displacement of the movable member 31 can be suppressed and the foaming pressure can be directed to the discharge port 18 more effectively, the bubble pressure can contribute to the discharge more efficiently. be able to.
[0088]
Example 3
FIG. 9 is a schematic cross-sectional view of a third embodiment of the liquid discharge head of the present invention.
[0089]
This embodiment also uses the same movable member 31 as in the first embodiment, but the thickness gradually decreases from the fulcrum 33 toward the free end 32. Thereby, when the movable member 31 is displaced, the resistance due to the liquid existing in the liquid flow path 10 is further reduced, and the displacement of the free end 32 can be increased. It can grow toward the discharge port 18.
[0090]
Example 4
FIG. 10 shows a fourth embodiment of the present invention. In FIG. 10, A shows a state in which the movable member 31 is displaced (bubbles are not shown), B shows a state in which the movable member 31 is in the initial position (first position), and in this B state, It is assumed that the bubble generation region 11 is substantially sealed with respect to the discharge port 18. (Although not shown here, there is a channel wall between A and B to separate the channel from the channel.)
The movable member 31 in FIG. 10 has the same shape as that of the first embodiment. In addition, two bases 34 are provided on the side, and the liquid supply path 12 is provided therebetween. Thereby, the liquid can be supplied from the liquid supply path having a surface that is substantially flat or smoothly connected to the surface of the heat generating element 2 along the surface of the movable member 31 on the heat generating element 2 side.
[0091]
Here, at the initial position (first position) of the movable member 31, the movable member 31 is close to or in close contact with the heating element downstream wall 36 and the heating element side wall 37 arranged on the downstream side and the lateral direction of the heating element 2. The bubble generation region 11 is substantially sealed on the discharge port 18 side. For this reason, the pressure of the bubble at the time of foaming, in particular, the pressure on the downstream side of the bubble can be concentratedly applied to the free end 32 side of the movable member 31.
[0092]
Further, at the time of defoaming, the movable member 31 returns to the first position, and the liquid supply at the time of defoaming onto the heating element 2 is substantially sealed at the discharge port 18 side of the bubble generation region 11. Various effects described in the previous embodiments, such as suppression, can be obtained. In addition, the same functions and effects as in the previous embodiment can be obtained in the effects related to refilling.
[0093]
Further, in this embodiment, as shown in FIGS. 2 and 10, the base 34 for supporting and fixing the movable member 31 is provided upstream from the heating element 2 and has a width smaller than that of the liquid flow path 10. The liquid is supplied to the supply path 12 as described above. Further, the shape of the base 34 is not limited to this, and any shape can be used as long as refilling can be performed smoothly.
[0094]
In the present embodiment, the distance between the movable member 31 and the heating element 2 is about 15 μm, but it may be in a range where the pressure based on the generation of bubbles is sufficiently transmitted to the movable member 31.
[0095]
(Example 5)
FIG. 11 shows one of the basic concepts of the present invention, which is a fifth embodiment of the present invention. FIG. 11 shows the positional relationship between the bubble generation region 11 in one liquid flow path 10, the bubbles generated there, and the movable member 31, and the liquid discharge method and refill method by the liquid discharge head of the present invention are further improved. This is an example that is easy to understand.
[0096]
In many of the above-described embodiments, the pressure of the generated bubbles is concentrated on the free end 32 of the movable member 31, and the movement of the bubbles is concentrated on the discharge port 18 side at the same time when the movable member 31 is sharply moved. Has achieved. On the other hand, in the present embodiment, the downstream portion of the bubble, which is the bubble outlet 18 side that directly acts on the droplet discharge, is regulated on the free end 32 side of the movable member 31 while giving the degree of freedom of the generated bubbles. To do.
[0097]
Explaining in terms of configuration, in FIG. 11, as compared with the above-described FIG. 2 (Example 1), a convex portion as a barrier (FIG. 2) located at the downstream end of the bubble generation region provided on the element substrate 1 in FIG. 1) is not provided in this embodiment. That is, the free end region and both end regions of the movable member 31 are open without substantially sealing the bubble generation region 11 with respect to the discharge port region. Other shapes of the movable member 31 are the same as those in the first embodiment.
[0098]
In the present embodiment, among the downstream portions directly acting on the bubble droplet ejection, the bubble growth at the downstream tip is allowed, so the pressure component is effectively used for ejection. In addition, the pressure (V in FIG. ₁ , V ₂ , V _Three Therefore, the free end side portion of the movable member 31 is added to the bubble growth at the downstream end portion, so that the discharge efficiency is improved in the same manner as in the above-described embodiment. Compared with the above-described embodiment, this embodiment is superior in response to driving of the heating element 2.
[0099]
In addition, this embodiment has a manufacturing advantage since it is simple in structure.
[0100]
The fulcrum portion of the movable member 31 of this embodiment is fixed to one base 34 having a small width with respect to the surface portion of the movable member 31. Therefore, the liquid supply to the bubble generation region 11 at the time of defoaming is supplied through both sides of the base 34 (see arrows in the figure). The base 34 may have any structure as long as it can secure supply.
[0101]
In the case of the present embodiment, the refill at the time of supplying the liquid is controlled by the presence of the movable member 31 so that the flow flowing into the bubble generation region 11 from above is controlled as the bubbles disappear. It is excellent for the bubble generation structure. Of course, this also reduces the amount of meniscus retraction.
[0102]
As a modified example of the present embodiment, it is preferable that only the both side ends (or one side) of the movable member 31 with respect to the free end 32 be substantially sealed with respect to the bubble generation region 11. According to this configuration, the pressure toward the side of the movable member 31 can also be used by changing it to the growth of the bubble discharge port side end portion described above, so that the discharge efficiency is further improved.
[0103]
(Example 6)
An example in which the liquid ejection force due to the mechanical displacement described above is further improved will be described in the present embodiment. FIG. 12 is a cross-sectional view of such a head structure. FIG. 12 shows an embodiment in which the movable member 31 extends so that the position of the free end 32 of the movable member 31 is located further downstream of the heating element 2. As a result, the displacement speed of the movable member 31 at the free end position can be increased, and the generation of discharge force due to the displacement of the movable member 31 can be further improved. Other shapes of the movable member 31 are the same as those in the first embodiment.
[0104]
In addition, since the free end 32 is closer to the discharge port 18 as compared with the previous embodiment, the growth of the bubbles 40 can be concentrated in a more stable directional component, so that more excellent discharge can be performed.
[0105]
Further, the movable member 31 is displaced at the displacement speed R1 according to the bubble growth speed at the pressure center of the bubble 40, but the free end 32 at a position farther from the fulcrum 33 than this position is displaced at a higher speed R2. . Thus, the discharge efficiency is increased by causing the free end 32 to mechanically act on the liquid at a high speed to cause liquid movement.
[0106]
(Example 7)
FIGS. 13A, 13B, and 13C show Example 7 of the present invention.
[0107]
Unlike the previous embodiment, the structure of the present embodiment does not have a flow channel shape communicating with the liquid chamber side directly in the region that communicates with the discharge port 18, and the structure can be simplified.
[0108]
All the liquid supply is performed only from the supply path 12 along the surface of the movable member 31 on the bubble generation region side. The shape of the movable member 31, the positional relationship of the free end 32 and the fulcrum 33 with respect to the discharge port 18, the heating element, and the like. The configuration facing 2 is the same as in the previous embodiment.
[0109]
This example realizes the above-mentioned effects such as discharge efficiency and liquid supply property, but particularly suppresses meniscus retraction and uses the pressure during defoaming to remove almost all liquid supply during defoaming. Forced refill is performed using the pressure of
[0110]
FIG. 13A shows a state in which the liquid is foamed by the heating element 2, and FIG. 13B shows a state in which the foaming is contracting. At this time, the return of the movable member 31 to the initial position is shown. Liquid supply by S3 is performed.
[0111]
FIG. 13C shows a state where a slight meniscus retraction when the movable member 31 returns to the initial position is refilled by the capillary force in the vicinity of the discharge port 18 after defoaming.
[0112]
(Example 8)
Embodiment 8 of the present invention will be described below with reference to FIGS.
[0113]
In this embodiment, the main liquid discharge principle is the same as that of the previous embodiment. However, in this embodiment, the liquid flow path has a multi-flow path configuration, and further, a liquid that is foamed by applying heat ( The foaming liquid) and the liquid that is mainly discharged (discharge liquid) can be separated.
[0114]
FIG. 14 is a schematic cross-sectional view of the liquid discharge head of the present embodiment in the flow path direction, and FIG. 15 is a partially broken perspective view of the liquid discharge head.
[0115]
The liquid discharge head according to the present embodiment has a second liquid flow path 16 for foaming on an element substrate 1 provided with a heating element 2 that gives thermal energy for generating bubbles in the liquid. A first liquid flow path 14 for discharge liquid that communicates directly with the outlet 18 is disposed. The upstream side of the first liquid channel 14 communicates with the first common liquid chamber 15 for supplying the discharge liquid to the plurality of first liquid channels 14, and the upstream side of the second liquid channel 16 is It communicates with a second common liquid chamber 17 for supplying the foaming liquid to the plurality of second liquid flow paths 16.
[0116]
A separation wall 30 made of a material having elasticity such as metal is disposed between the first liquid flow path 14 and the second liquid flow path 16, and the first liquid flow path 14 and the second liquid flow path. The road 16 is separated. In the case where the foam liquid and the discharge liquid should not be mixed as much as possible, the liquid in the first liquid passage 14 and the second liquid passage 16 can be completely distributed by the separation wall 30 as much as possible. Although it is better to separate, if there is no problem even if the foaming liquid and the discharge liquid are mixed to some extent, the separation wall 30 may not have the function of complete separation.
[0117]
A portion of the separation wall 30 located in a projection space (hereinafter referred to as a discharge pressure generation region; hereinafter, region A and bubble generation region 11 in FIG. 14) of the heating element 2 is discharged by a slit 35. A free end 32 is provided on the outlet 18 side (downstream side of the liquid flow), and a cantilever-shaped movable member 31 having a fulcrum 33 positioned on the common liquid chamber (15, 17) side is formed. Since this movable member 31 is arranged facing the bubble generation region 11 (B), it operates so as to open toward the discharge port 18 side on the first liquid flow path 14 side by foaming of the foaming liquid ( Arrow direction in the figure). Also in FIG. 15, the space constituting the second liquid flow path on the element substrate 1 on which the heating resistor portion as the heating element 2 and the wiring electrode 5 for applying an electric signal to the heating resistor portion are arranged. A separation wall 30 is arranged via the.
[0118]
The relationship between the arrangement of the fulcrum 33 and the free end 32 of the movable member 31 and the arrangement of the heating element 2 is the same as in the previous embodiment. Further, the cross-sectional shape of the movable member 31 in the width direction is a shape in which the width is gradually narrowed from the surface facing the heating element 2 toward the opposite surface as in the previous embodiment. The resistance to the liquid in the first liquid channel 14 when the movable member 31 is displaced is reduced.
[0119]
In the previous embodiment, the relationship between the structure of the liquid supply path 12 and the heating element 2 has been described. However, the structure of the second liquid flow path 16 and the heating element 2 is the same in this embodiment. .
[0120]
Next, the operation of the liquid discharge head of this embodiment will be described with reference to FIG.
[0121]
In driving the head, it was operated using the same water-based ink as the discharge liquid supplied to the first liquid flow path 14 and the foaming liquid supplied to the second liquid flow path 16. The heat generated by the heating element 2 acts on the foaming liquid in the bubble generation region 11 of the second liquid flow path 16, so that the foaming liquid is described in US Pat. No. 4,723,129 as described in the previous embodiment. The bubble 40 based on the film boiling phenomenon as described above is generated.
[0122]
In this embodiment, since there is no escape of the foaming pressure from the three sides except for the upstream side of the bubble generation region 11, the pressure associated with the bubble generation is concentrated on the movable member 31 side arranged in the discharge pressure generation unit. As the bubble 40 grows, the movable member 31 is displaced from the state shown in FIG. 16A toward the first liquid channel 14 as shown in FIG. By the operation of the movable member 31, the first liquid channel 14 and the second liquid channel 16 are greatly communicated, and the pressure based on the generation of the bubbles 40 is the direction of the discharge port side of the first liquid channel 14 (A direction). To the Lord. The liquid is discharged from the discharge port by the propagation of the pressure and the mechanical displacement of the movable member 31 as described above.
[0123]
Next, as the bubble 40 contracts, the movable member 31 returns to the position shown in FIG. 16A, and an amount of discharged liquid corresponding to the amount of discharged liquid is discharged from the upstream side in the first liquid channel 14. Supplied. Also in this embodiment, since the supply of the discharge liquid is in the direction in which the movable member 31 is closed as in the above-described embodiment, refilling of the discharge liquid is not hindered by the movable member 31.
[0124]
In the present embodiment, the action and effect of the main parts relating to the fact that the movable member 31 is easily displaced, the propagation of the foaming pressure accompanying the displacement of the movable member 31, the growth direction of the bubble 40, the prevention of the back wave, etc. Although it is the same as 1 etc., there exist the following advantages by taking the 2 flow path structure like a present Example.
[0125]
That is, according to the configuration of the above-described embodiment, the discharge liquid and the foaming liquid can be separate liquids, and the discharge liquid can be discharged by the pressure generated by the foaming of the foaming liquid. For this reason, conventionally, even if it is a highly viscous liquid such as polyethylene glycol, which is not sufficiently foamed even when heat is applied and the discharge force is insufficient, this liquid is supplied to the first liquid flow path 14. As a foaming liquid, a liquid in which foaming is favorably performed (such as a mixed liquid of ethanol: water = 4: 6, about 1 to 2 cp) or a low boiling point liquid is supplied to the second liquid flow path 16 so as to be discharged well. it can.
[0126]
In addition, by selecting a liquid that does not produce deposits such as kogation on the surface of the heating element 2 even when receiving heat, foaming can be stabilized and good discharge can be performed.
[0127]
Furthermore, since the head structure of the present invention produces the effects described in the previous embodiments, it is possible to discharge liquid such as highly viscous liquid with higher discharge efficiency and higher discharge force.
[0128]
Further, even in the case of a liquid that is weak to heating, if this liquid is supplied to the first liquid flow path 14 as a discharge liquid, and a liquid that is not easily thermally altered in the second liquid flow path 16 and causes good foaming, The liquid that is weak to heating can be discharged with high discharge efficiency and high discharge force without causing thermal damage as described above.
[0129]
(Other examples)
As mentioned above, although the Example of the principal part of the liquid discharge head of this invention and the liquid discharge method was demonstrated, the example of an embodiment which can be applied preferably to these Examples is demonstrated using drawing below. However, in the following description, there are cases where either the above-described one-channel embodiment or the two-channel embodiment is taken up and explained. However, unless otherwise stated, it can be applied to both embodiments. is there.
[0130]
<Cross sectional shape of movable member in width direction>
In the embodiment described above, the shape as shown in FIG. 3 and the shape as shown in FIG. 8 are given as examples of the cross-sectional shape in the width direction of the movable member, but various other modifications can be considered. . Examples thereof are shown in FIG.
[0131]
The movable member 31 shown in FIGS. 17A to 17D is a modification of the movable member 31 shown in FIG. 3. The surface opposite to the heating element is a plane, and the shape of the opposite surface is the same. It has changed. In the movable member 31 shown in FIGS. 17E to 17H, the shape of the surface facing the heating element of the movable member 31 shown in FIGS. 17A to 17D is opposite to the heating element. It is the same as the shape of the surface, and both end portions in the width direction protrude from the central portion toward the heating element. Thereby, the same effect as the movable member 31 shown in FIG. 8 is acquired. The movable member 31 shown in FIG. 17 (i) is provided with further elevation portions at both ends in the width direction of the movable member 31 shown in FIG. 17 (a). This is also the movable member shown in FIG. 31 is a modified example.
[0132]
<Ceiling shape of liquid flow path>
FIG. 18 is a cross-sectional view of the liquid discharge head of the present invention in the direction of the flow path. The grooved member 50 provided with grooves for forming the first liquid flow path 14 (or the liquid flow path 10 in FIG. 1) is shown. It is provided on the separation wall 30. In this embodiment, the height of the flow path ceiling in the vicinity of the position of the free end 32 of the movable member 31 is high, so that the operating angle θ of the movable member 31 can be increased. The operation range of the movable member 31 may be determined in consideration of the structure of the liquid flow path, the durability of the movable member 31, the foaming force, and the like, but may operate up to an angle including the axial angle of the discharge port 18. Is considered desirable. As shown in FIG. 9, the operating angle θ of the movable member 31 can be further increased by gradually reducing the thickness of the movable member 31 from the fulcrum 33 toward the free end 32.
[0133]
Further, as shown in this figure, by making the displacement height of the free end 32 of the movable member 31 higher than the diameter of the discharge port 18, more sufficient discharge force can be transmitted. Further, as shown in this figure, the height of the liquid flow path ceiling at the fulcrum 33 position of the movable member 31 is lower than the height of the liquid flow path ceiling at the position of the free end 32 of the movable member 31, The escape of the pressure wave to the upstream side due to the displacement of the movable member 31 can be more effectively prevented.
[0134]
<Arrangement relationship between second liquid flow path and movable member>
FIG. 19 is a view for explaining the positional relationship between the above-described movable member 31 and the second liquid flow path 16. FIG. 19A is a view of the separation wall 30 and the vicinity of the movable member 31 as viewed from above. FIG. 5B is a view of the second liquid channel 16 with the separation wall 30 removed as viewed from above. And (c) of the same figure is the figure which showed typically the arrangement | positioning relationship between the movable member 6 and the 2nd liquid flow path 16 by overlapping each of these elements. In each figure, the lower side of the drawing is the front side where the discharge ports are arranged.
[0135]
The second liquid flow path 16 of the present embodiment is upstream of the heating element 2 (the upstream side here is large from the second common liquid chamber side to the discharge port through the position of the heating element, the movable member, and the first flow path. A chamber (foaming chamber) that has a constricted portion 19 on the upstream side in the flow and suppresses the pressure during foaming from easily escaping to the upstream side of the second liquid channel 16. It has a structure.
[0136]
Like the conventional head, the flow path for foaming and the flow path for discharging liquid are the same, and the head is provided with a constricted portion so that the pressure generated on the liquid chamber side from the heating element does not escape to the common liquid chamber side In this case, it is necessary to take a configuration in which the cross-sectional area of the flow path in the narrowed portion is not so small in consideration of the refill of the liquid.
[0137]
However, in the case of the present embodiment, most of the discharged liquid can be used as the discharged liquid in the first liquid flow path, and the foamed liquid in the second liquid flow path 16 provided with the heating element 2 is not much consumed. Therefore, the filling amount of the foaming liquid into the bubble generation region of the second liquid channel 16 may be small. Therefore, since the interval in the narrowed portion 19 can be very narrow, such as several μm to several tens of μm, the pressure at the time of foaming generated in the second liquid flow path 16 can be further suppressed and concentrated. It can be directed to the movable member 31 side. And since this pressure can be utilized as discharge force via the movable member 31, higher discharge efficiency and discharge force can be achieved. However, the shape of the second liquid channel 16 is not limited to the above-described structure, and may be any shape as long as the pressure accompanying the generation of bubbles is effectively transmitted to the movable member 31 side.
[0138]
Note that the surface of the movable member 31 facing the heating element 2 is substantially flat, and further, the side of the movable member 31 forms the second liquid channel 16 as shown in FIG. Covers part of the wall. This can prevent the movable member 31 from dropping into the second liquid flow path 16. Thereby, the separability between the discharge liquid and the foaming liquid described above can be further enhanced. Further, since the escape of the bubbles from the slit 35 can be suppressed, the discharge pressure and the discharge efficiency can be further increased. Furthermore, the effect of the refill from the upstream side by the pressure at the time of the above-mentioned defoaming can be heightened.
[0139]
In FIG. 16B and FIG. 18, a part of the bubbles 40 generated in the bubble generation region 11 of the second liquid channel 16 due to the displacement of the movable member 31 toward the first liquid channel 14 side. Is extended to the first liquid flow path 14 side, but by setting the height of the second liquid flow path 16 so that the bubbles 40 extend in this way, compared to the case where the bubbles 40 do not extend. Further, the discharge force can be improved. In order to allow the bubbles 40 to extend to the first liquid flow path 14 in this way, it is desirable to make the height of the second liquid flow path 16 lower than the height of the maximum bubble, and this height is several μm. It is desirable that the thickness be ˜30 μm. In the present embodiment, this height is 15 μm.
[0140]
<Moveable member and separation wall>
FIG. 20 shows another planar shape of the movable member 31. Reference numeral 35 denotes a slit provided in the separation wall, and the movable member 31 is formed by the slit 35. (A) is a rectangular shape, (b) is a shape in which the fulcrum side is narrow and the movable member is easy to operate, and (c) in FIG. This is a shape in which the durability of 31 is improved. As shown in FIG. 19 (a), it is desirable that the shape of the movable member 31 be the second liquid, although the shape on which the fulcrum side is narrowed in an arc shape is desirable as a shape having good ease of operation and durability. Any shape that does not enter the flow path 16 side, can be easily operated, and has excellent durability may be used.
[0141]
In the previous embodiment, the plate-shaped movable member 31 and the separation wall having the movable member 31 are made of nickel having a thickness of 5 μm, but the material constituting the movable member 31 and the separation wall is not limited to this. As long as it has solvent resistance with respect to the foaming liquid and the discharge liquid, has elasticity for operating as the movable member 31, and can control the formation of the slit and the shape in the thickness direction.
[0142]
The material of the movable member 31 is a highly durable metal such as silver, nickel, gold, iron, titanium, aluminum, platinum, tantalum, stainless steel, phosphor bronze, and alloys thereof, or acrylonitrile, butadiene, styrene, etc. Resins having a nitrile group, resins having an amide group such as polyamide, resins having a carboxyl group such as polycarbonate, resins having an aldehyde group such as polyacetal, resins having a sulfone group such as polysulfone, other resins such as liquid crystal polymers and the like Compounds, metals with high ink resistance, metals such as gold, tungsten, tantalum, nickel, stainless steel, titanium, alloys thereof and ink resistance, those coated on the surface, or resins having an amide group such as polyamide, Aldehydes such as polyacetal Resin having a ketone group such as polyetheretherketone, resin having an imide group such as polyimide, resin having a hydroxyl group such as phenol resin, resin having an ethyl group such as polyethylene, alkyl group such as polypropylene Resins, resins having epoxy groups such as epoxy resins, resins having amino groups such as melamine resins, resins having methylol groups such as xylene resins and compounds thereof, and ceramics such as silicon dioxide and compounds thereof are desirable.
[0143]
The material of the separation wall 30 is polyethylene, polypropylene, polyamide, polyethylene terephthalate, melamine resin, phenol resin, epoxy resin, polybutadiene, polyurethane, polyether ether ketone, polyether sulfone, polyarylate, polyimide, polysulfone, liquid crystal polymer ( Resins having good heat resistance, solvent resistance, moldability, and their compounds represented by recent engineering plastics such as LCP), and their compounds, or metals such as silicon dioxide, silicon nitride, nickel, gold, stainless steel, alloys, and the like Those compounds, or those coated with titanium or gold on the surface are desirable.
[0144]
Further, the thickness of the separation wall 30 may be determined in consideration of the material, shape, and the like from the viewpoint that the strength as the separation wall 30 can be achieved and the movable member 31 operates favorably. About 10 μm is desirable.
[0145]
Although the width of the slit 35 for forming the movable member 31 is 2 μm in this embodiment, the foaming liquid and the discharge liquid are different liquids. The distance between the liquids is such that a meniscus is formed, and the flow of each liquid may be suppressed. For example, when a liquid of about 2 cp (centipoise) is used as the foaming liquid and a liquid of 100 cp or more is used as the discharge liquid, a mixed liquid can be prevented even with a slit of about 5 μm, but it is desirable that the liquid be 3 μm or less. .
[0146]
The movable member in the present invention is intended for a thickness (μm) on the order of μm, and a movable member with a thickness on the order of cm is not intended. For a movable member having a thickness on the order of μm, when a slit width (W μm) on the order of μm is targeted, it is desirable to consider manufacturing variations to some extent.
[0147]
The slit that gives the “substantially sealed state” of the present invention is more reliable if it is on the order of several μm.
[0148]
As described above, when the foaming liquid and the discharge liquid are function-separated, the movable member becomes the substantial partition member. It can be seen that the foaming liquid is slightly mixed with the discharge liquid when the movable member moves as the bubbles are generated. In consideration of the fact that the discharge liquid for forming an image generally has a colorant concentration of about 3% to 5% in the case of ink jet recording, the foaming liquid is in a range of 20% or less with respect to the discharge droplets. Even if it is contained in, it does not cause a large concentration change. Therefore, as such a mixed liquid, the present invention includes a mixture of a foaming liquid and a discharged liquid that is 20% or less with respect to the discharged liquid droplets.
[0149]
In the implementation of the above configuration example, even if the viscosity is changed, the upper limit is 15% of the foaming liquid, and in the case of the foaming liquid of 5 cp or less, the mixing ratio is about 10% although it depends on the driving frequency. It was the upper limit.
[0150]
In particular, the liquid mixture can be reduced (for example, 5% or less) as the viscosity of the discharged liquid is reduced to 20 cp or less.
[0151]
Next, the positional relationship between the heating element and the movable member in this head will be described with reference to the drawings. However, the shape, size, and number of the movable member and the heating element are not limited to the following. By optimal arrangement of the heating element and the movable member, the pressure at the time of foaming by the heating element can be effectively used as the discharge pressure.
[0152]
By applying energy such as heat to the ink, the ink undergoes a change in state accompanied by a steep volume change (bubble generation), and the ink is discharged from the discharge port by the action force based on this change in state, and this is recorded In the conventional technique of the ink jet recording method in which an image is formed by adhering to a medium, that is, the so-called bubble jet recording method, as shown in FIG. 21, the heating element area and the ink discharge amount are in a proportional relationship, but contribute to ink discharge. It can be seen that there is a non-foaming effective region S that does not. Further, it can be seen from the state of the kogation on the heating element that this non-foaming effective region S exists around the heating element. From these results, the width of about 4 μm around the heating element is not involved in foaming.
[0153]
Therefore, in order to effectively use the foaming pressure, it is effective to dispose the movable member so that the movable region of the movable member covers the portion immediately above the effective foaming region about 4 μm or more from the periphery of the heating element. I can say. In this embodiment, the effective foaming area is set to about 4 μm or more inside from the periphery of the heating element, but it is not limited to this depending on the type of heating element and the forming method.
[0154]
FIG. 22 is a schematic view seen from above when a movable member 31a (FIG. (A)) and a movable member 31b (FIG. (B)) having different total areas of movable regions are arranged on the heating element 2 of 58 × 150 μm. Show.
[0155]
The dimension of the movable member 31a is 53 × 145 μm, which is smaller than the area of the heating element 2, but is the same size as the effective foaming area of the heating element 2, and is arranged so as to cover the effective foaming area. . On the other hand, the dimension of the movable member 31b is 53 × 220 μm, which is larger than the area of the heating element 2 (when the width dimension is the same, the dimension between the fulcrum 33 and the movable tip is longer than the length of the heating element 2) and is movable. It arrange | positions so that the foaming effective area | region may be covered similarly to the member 31a. The durability and discharge efficiency of the two types of movable members 31a and 31b were measured. The measurement conditions are as follows.
[0156]
Foaming solution: Ethanol 40% aqueous solution
Discharge ink: Dye ink
Voltage: 20.2V
Frequency: 3kHz
As a result of experiments conducted under these measurement conditions, regarding the durability of the movable member, (a) the movable member 31a is 1 × 10 ⁷ When the pulse was applied, damage was observed at the fulcrum portion of the movable member 31a. (B) The movable member 31b is 3 × 10 ⁸ No damage was observed even when the pulse was applied. It was also confirmed that the kinetic energy obtained from the discharge amount and discharge speed relative to the input energy was improved by about 1.5 to 2.5 times.
[0157]
From the above results, from the viewpoint of both durability and discharge efficiency, a movable member is provided so as to cover just above the effective foaming region, and the area of the movable member is larger than the area of the heating element. I understand that.
[0158]
FIG. 23 shows the relationship between the distance from the edge of the heating element to the fulcrum of the movable member and the amount of displacement of the movable member. FIG. 24 is a cross-sectional configuration diagram of the positional relationship between the heating element 2 and the movable member 31 as viewed from the side. A heating element 2 of 40 × 105 μm was used. It can be seen that the greater the distance l from the edge of the heating element 2 to the fulcrum 33 of the movable member 31, the greater the displacement. Therefore, it is desirable to determine the optimum displacement amount and determine the position of the fulcrum 33 of the movable member 31 according to the required ink discharge amount, the flow path structure of the discharge liquid, and the heating element shape.
[0159]
Further, when the fulcrum 33 of the movable member 31 is located immediately above the effective foaming region of the heating element 2, the foaming pressure is directly applied to the fulcrum 33 in addition to the stress caused by the displacement of the movable member 31. Resulting in. According to the experiment of the present inventor, in the case where the fulcrum 33 is provided right above the effective foaming region, 1 × 10 ⁶ It is known that the movable wall is damaged at a pulse level, and the durability is lowered. Therefore, if the fulcrum 33 of the movable member 31 is disposed directly above and outside the effective foaming region of the heating element 2, even if it is the movable member 31 having a shape or material that is not so durable, the practical possibility increases. However, even when the fulcrum 33 is directly above the effective foaming region, it can be used satisfactorily if the shape and material are selected. In such a configuration, a liquid discharge head excellent in high discharge efficiency and durability can be obtained.
[0160]
<Element substrate>
The structure of the element substrate provided with a heating element for applying heat to the liquid will be described below.
[0161]
FIG. 25 is a longitudinal sectional view of the liquid discharge head of the present invention. FIG. 25 (a) shows a head having a protective film (anti-cavitation layer) described later, and FIG. 25 (b) shows a head without a protective film. is there.
[0162]
On the element substrate 1, a second liquid channel 16, a separation wall 30, a first liquid channel 14, and a grooved member 50 provided with grooves constituting the first liquid channel 14 are arranged.
[0163]
On the element substrate 1, a silicon oxide film or silicon nitride film 106 for insulating and heat storage is formed on a base 107 such as silicon, and a hafnium boride (HfB) constituting the heating element 2 is formed thereon. ₂ ), An electric resistance layer 105 (0.01-0.2 μm thickness) such as tantalum nitride (TaN), tantalum aluminum (TaAl), and a wiring electrode (0.2-1.0 μm thickness) such as aluminum, etc. It is patterned as follows. A voltage is applied to the electric resistance layer 105 from the two wiring electrodes 104, and a current is passed through the electric resistance layer 105 to generate heat. A protective layer 103 such as silicon oxide or silicon nitride is formed with a thickness of 0.1 to 2.0 μm on the electric resistance layer 105 between the wiring electrodes 104, and a cavitation-resistant layer 102 (0.1 ˜0.6 μm thick), and the electric resistance layer 105 is protected from various liquids such as ink.
[0164]
In particular, the pressure and shock wave generated when bubbles are generated and defoamed are very strong, and the durability of the hard and fragile oxide film is remarkably lowered. Therefore, a metal material such as tantalum (Ta) is used as the anti-cavitation layer 102. It is done.
[0165]
Moreover, the structure which does not require the above-mentioned cavitation-proof layer 102 with the combination of a liquid, a liquid flow path structure, and a resistance material may be sufficient, and the example is shown in FIG.25 (b). Examples of the material of the electric resistance layer 105 that does not require such an anti-cavitation layer include iridium-tantalum-aluminum alloy.
[0166]
Thus, the configuration of the heating element 2 in each of the above-described embodiments may be only the electrical resistance layer (heating unit) 105 between the wiring electrodes 104 described above, and the protective layer 103 that protects the electrical resistance layer 105 is provided. It may be included.
[0167]
In the present embodiment, the heating element 2 having a heat generating portion composed of the electric resistance layer 105 that generates heat in response to an electric signal is used. However, the present invention is not limited to this, and it is sufficient for discharging the discharge liquid. What is necessary is just to produce a sufficient bubble in a foaming liquid. For example, a light-to-heat conversion body that generates heat when receiving light from a laser or the like as a heat generating section, or a heating element that includes a heat generating section that generates heat by receiving high frequency may be used.
[0168]
In addition to the electrothermal transducer formed of the above-described element substrate 1 including the electrical resistance layer 105 that constitutes the above-described heat generating portion and the wiring electrode 104 for supplying an electrical signal to this electrical resistance layer 105, Functional elements such as a transistor, a diode, a latch, and a shift register for selectively driving the electrothermal conversion element may be integrally formed by a semiconductor manufacturing process.
[0169]
Further, in order to drive the heat generating portion of the electrothermal transducer provided on the element substrate 1 as described above and to discharge the liquid, the electric resistance layer 105 is shown in FIG. Such a rectangular pulse is applied, and the electric resistance layer 105 between the wiring electrodes 104 is rapidly heated. In the heads of the above-described embodiments, the heating element is driven by applying a voltage of 24 V, a pulse width of 7 μsec, a current of 150 mA, and an electric signal at 6 kHz, and the ink as liquid is discharged from the ejection port 18 by the operation as described above. Was discharged. However, the condition of the drive signal is not limited to this, and any drive signal that can appropriately foam the foaming liquid may be used.
[0170]
<Head structure with two flow paths>
In the following, an example of the structure of a liquid discharge head will be described in which different liquids can be well separated and introduced into the first and second common liquid chambers, the number of parts can be reduced, and the cost can be reduced.
[0171]
FIG. 27 is a schematic diagram showing the structure of such a liquid discharge head. The same reference numerals are used for the same components as in the previous embodiment, and detailed description thereof is omitted here.
[0172]
In the present embodiment, the grooved member 50 is common to the orifice plate 51 having the discharge port 18, the plurality of grooves constituting the plurality of first liquid flow paths 14, and the plurality of first liquid flow paths 14. It is generally configured from a recess that constitutes a first common liquid chamber 15 for communicating and supplying a liquid (discharge liquid) to each first liquid flow path 14.
[0173]
A plurality of first liquid flow paths 14 can be formed by joining the separation wall 30 to the lower portion of the grooved member 50. The grooved member 50 has a first liquid supply path 20 that reaches the first common liquid chamber 15 from the upper part thereof. Further, the grooved member 50 has a second liquid supply path 21 that penetrates the separation wall 30 from the upper part and reaches the second common liquid chamber 17.
[0174]
As shown by an arrow C in FIG. 27, the first liquid (discharge liquid) is supplied to the first common liquid chamber 15 and then to the first liquid flow path 14 via the first liquid supply path 20, and the second liquid The liquid (foamed liquid) is supplied to the second common liquid chamber 17 and then the second liquid flow path 16 through the second liquid supply path 21 as indicated by an arrow D in FIG.
[0175]
In the present embodiment, the second liquid supply path 21 is arranged in parallel with the first liquid supply path 20, but is not limited to this, and the separation arranged outside the first common liquid chamber 15. It may be arranged in any way as long as it is formed so as to penetrate the wall 30 and communicate with the second common liquid chamber 17.
[0176]
Further, the thickness (diameter) of the second liquid supply path 21 is determined in consideration of the supply amount of the second liquid. The shape of the second liquid supply path 21 does not have to be round, and may be rectangular.
[0177]
The second common liquid chamber 17 can be formed by partitioning the grooved member 50 with the separation wall 30. As a forming method, as shown in the exploded perspective view of the present embodiment shown in FIG. 28, the common liquid chamber frame 71 and the second liquid passage wall 72 are formed on the element substrate 1 with a dry film, and the separation wall 30 is fixed. The second common liquid chamber 17 and the second liquid flow path 16 may be formed by bonding the combined body of the grooved member 50 and the separation wall 30 to the element substrate 1.
[0178]
In the present embodiment, as described above, electrothermal conversion as a heating element that generates heat for generating bubbles due to film boiling of the foamed liquid on the support 70 formed of a metal such as aluminum. An element substrate 1 provided with a plurality of elements is disposed.
[0179]
On the element substrate 1, a plurality of grooves constituting the second liquid flow path 16 formed by the second liquid path wall 72 and a plurality of foam liquid flow paths are communicated with each other. Are provided with a concave portion constituting a second common liquid chamber (common foaming liquid chamber) 17 and a separation wall 30 provided with the movable wall 31 described above.
[0180]
The grooved member 50 is connected to the separation wall 30 so as to communicate with the grooves constituting the discharge liquid flow path (first liquid flow path) 14 and the discharge liquid flow path. A first common liquid chamber (common discharge liquid chamber) 15 for supplying the liquid, and a first liquid supply path (discharge liquid supply path) for supplying the discharge liquid to the first common liquid chamber 15 20 and a second liquid supply path (foaming liquid supply path) 21 for supplying the foaming liquid to the second common liquid chamber 17. The second supply path 21 is connected to a communication path that passes through the separation wall 30 disposed outside the first common liquid chamber 15 and communicates with the second common liquid chamber 17. The foaming liquid can be supplied to the second common liquid chamber 17 without mixing.
[0181]
With respect to the arrangement relationship of the element substrate 1, the separation wall 30, and the grooved member 50, a movable member 31 is arranged corresponding to the heating element 2 of the element substrate 1, and the discharge liquid flow path 14 corresponds to this movable member 31. Is arranged. Moreover, although the example which distribute | arranged the one 2nd liquid supply path 21 to the grooved member 50 was shown in this embodiment, you may provide two or more according to supply amount. Furthermore, the cross-sectional area of the first liquid supply path 20 and the second liquid supply path 21 may be determined in proportion to the supply amount. By optimizing the cross-sectional area of the flow path, it is possible to further reduce the size of the parts constituting the grooved member 50 and the like.
[0182]
As described above, according to the present embodiment, the second liquid supply passage 21 that supplies the second liquid to the second liquid passage 16 and the first liquid supply that supplies the first liquid to the first liquid passage 14. Since the path 20 is made of the same grooved member 50, the number of parts can be reduced, and the process can be shortened and the cost can be reduced.
[0183]
The second liquid is supplied to the second common liquid chamber 17 communicating with the second liquid flow path 16 by the second liquid flow path 16 in a direction penetrating the separation wall 30 that separates the first liquid and the second liquid. Since the structure is performed, the bonding process of the separation wall 30, the grooved member 50, and the element substrate 1 can be performed only once, improving the ease of manufacturing, improving the bonding accuracy, and discharging well. be able to.
[0184]
In addition, since the second liquid penetrates the separation wall 30 and is supplied to the second common liquid chamber 17, the second liquid can be reliably supplied to the second liquid flow path 16, and the supply amount can be sufficiently secured. Can be discharged.
[0185]
<Discharged liquid, foamed liquid>
As described in the previous embodiment, in the present invention, the structure having the movable member as described above can discharge liquid at a high speed with higher discharge force and discharge efficiency than the conventional liquid discharge head. In the present embodiment, when the same liquid is used for the foaming liquid and the discharge liquid, it does not deteriorate due to the heat applied from the heating element, and it is difficult to cause deposits on the heating element by heating, and it is vaporized by heat. Various liquids can be used as long as they can reversibly change the state of condensation and do not deteriorate the liquid flow path, the movable member, the separation wall, and the like.
[0186]
Among such liquids, as a liquid (recording liquid) used for recording, ink having a composition used in a conventional bubble jet apparatus can be used.
[0187]
On the other hand, in the case of using the two-flow path head of the present invention and the discharge liquid and the foaming liquid are separate liquids, the liquid having the above-described properties may be used as the foaming liquid. Ethanol, n-propanol, isopropanol, n-hexane, n-heptane, n-octane, toluene, xylene, methylene dichloride, trichrene, freon TF, freon BF, ethyl ether, dioxane, cyclohexane, methyl acetate, ethyl acetate, acetone , Methyl ethyl ketone, water and the like and mixtures thereof.
[0188]
As the discharge liquid, various liquids can be used regardless of the presence or absence of foamability and thermal properties. Further, it can be used even for liquids that have been difficult to discharge, such as liquids with low foamability, liquids that are easily altered or deteriorated by heat, and high-viscosity liquids.
[0189]
However, it is desirable that the liquid is not a liquid that obstructs discharge, foaming, operation of the movable member, or the like due to a reaction with the discharge liquid itself or the foam liquid as a property of the discharge liquid.
[0190]
High viscosity ink or the like can also be used as the recording discharge liquid. As other discharge liquids, liquids such as medicines and perfumes that are weak against heat can be used.
[0191]
In the present invention, recording was performed using an ink having the following composition as a recording liquid that can be used for both the ejection liquid and the foaming liquid, but because the ejection speed of the ink increased due to the improvement in ejection force, The droplet landing accuracy was improved and a very good recorded image could be obtained.
[0192]
[Outside 1]

[0193]
In addition, recording was performed by discharging a foamed liquid and a discharge liquid in combination with a liquid having the following composition. As a result, not only a liquid with a dozen cp viscosity, which was difficult to discharge with a conventional head, but also a liquid with a very high viscosity of 150 cp could be discharged well, and a high-quality recorded matter could be obtained.
[0194]
[Outside 2]

[0195]
By the way, in the case of the liquid that has been conventionally difficult to be ejected as described above, since the ejection speed is low, the variation in ejection directionality is promoted, the dot landing accuracy on the recording paper is poor, and the ejection is unstable. Variations in the discharge amount occurred, and it was difficult to obtain a high-quality image. However, in the configuration of the above-described embodiment, bubbles can be generated sufficiently and stably by using the foaming liquid. As a result, the droplet landing accuracy can be improved and the ink discharge amount can be stabilized, and the quality of the recorded image can be remarkably improved.
[0196]
<Manufacture of movable members>
Next, examples of the manufacturing process of the movable member, which is the greatest feature of the present invention, will be described by selecting some of the various shapes shown in the above-described embodiments.
[0197]
First, an example of the manufacturing method of the movable member 31 shown in FIG. 3 will be described with reference to FIGS.
[0198]
(A) A resist 1101 having a thickness of 0.5 μm is patterned on the SUS substrate 1100. The width of the resist 1101 to be patterned is 12 μm in the case of a resist having a thickness of 0.5 μm, where the width left as a slit is 3 μm.
[0199]
(B) Electroplating is performed on the SUS substrate 1100 to grow a nickel layer 1102 on the SUS substrate 1100 by 5 μm. As a plating solution, a stress reducing agent (manufactured by World Metal: Zeolol), boric acid, a pit preventing agent (manufactured by World Metal: NP-APS), and nickel chloride were used for nickel sulfamate. The method of applying an electric field during electrodeposition is to attach an electrode on the anode side, attach a SUS substrate 1100 already patterned with a resist 1101 on the cathode side, set the temperature of the plating solution to 50 ° C., and set the current density to 5 A / cm. ² It was.
[0200]
When the nickel layer 1102 is grown under these conditions, the nickel layer 1102 grows in a direction covering the resist 1101 in addition to the thickness direction from the time when the nickel layer 1102 is grown by 0.5 μm. When the total thickness becomes 5 μm, the nickel layer 1102 covers about 4.5 μm on both sides of the resist 1101. As a result, a gap having a width of 3 μm is formed on the resist 1101 along the pattern of the resist 1101, and the radius of curvature in the thickness direction of the nickel layer 1102 at this gap is 4.5 μm.
[0201]
(C) Ultrasonic vibration is applied to the plated SUS substrate 1100 to peel off the nickel layer 1102 from the SUSU substrate 1100, thereby obtaining the movable member 31 having a shape in which the width gradually decreases upward in the figure. .
[0202]
Here, a step which is a trace of the resist 1101 is formed on the lower surface of the movable member 31 in the figure. Since the height of the step is 0.5 μm, the lower surface of the movable member 31 is substantially flat. .
[0203]
Next, an example of a manufacturing method of the movable member 31 shown in FIG. 17C will be described with reference to FIGS.
[0204]
(A) A resist 1101a having a thickness of 2.5 μm is patterned on the SUS substrate 1100. The width of the resist 1101a to be patterned is adjusted to the width to be left as a slit.
[0205]
(B) Electroplating is performed on the SUS substrate 1100 to grow a nickel layer 1102a on the SUS substrate 1100 by 2.5 μm. As a plating solution, a stress reducing agent (manufactured by World Metal: Zeolol), boric acid, a pit preventing agent (manufactured by World Metal: NP-APS), and nickel chloride were used for nickel sulfamate. The method of applying an electric field during electrodeposition is to attach an electrode on the anode side, attach a SUS substrate 1100 already patterned with resists 1101a and 1101b to the cathode side, set the temperature of the plating solution to 50 ° C., and a current density of 5 A / cm. ² It was.
[0206]
(C) Overlaying the resist 1101a described above, the resist 1101b having a thickness of 2.5 μm is patterned again. The width of the resist 110b is assumed to be larger than the width of the resist 1101a patterned first.
[0207]
(D) The above nickel layer 1102a is electroplated again to grow a second nickel layer 1102b by 2.5 μm. The plating conditions are the same as when the first nickel layer 1102a is formed.
[0208]
(E) After removing the resists 1101a and 1101b, ultrasonic vibration is applied to the SUS substrate 1100, and the first nickel layer 1102a is peeled from the SUS substrate 1100 to obtain a two-stage movable member 31.
[0209]
Next, an example of a manufacturing method of the movable member 31 shown in FIG. 17 (d) will be described with reference to FIGS. 31 (a) to 31 (c).
[0210]
(A) A resist 1101 having a thickness of 15 μm is patterned on the SUS substrate 1100. At this time, the focal point at the time of exposure is shifted so that the side surface of the patterned resist 1101 is inclined.
[0211]
(B) Electroplating is performed on the SUS substrate 1100 to grow a nickel layer 1102 on the SUS substrate 1100 by 5 μm. As a plating solution, a stress reducing agent (manufactured by World Metal: Zeolol), boric acid, a pit preventing agent (manufactured by World Metal: NP-APS), and nickel chloride were used for nickel sulfamate. The method of applying an electric field during electrodeposition is to attach an electrode on the anode side, attach a SUS substrate 1100 already patterned with a resist 1101 on the cathode side, set the temperature of the plating solution to 50 ° C., and set the current density to 5 A / cm. ² It was.
[0212]
(C) Ultrasonic vibration is applied to the SUS substrate 1100 that has been plated as described above, and the nickel layer 1102 is peeled off from the SUS substrate 1100. When this is turned upside down, a trapezoidal movable member 31 is obtained.
[0213]
Next, an example of the manufacturing method of the movable member 31 shown in FIG. 17 (h) will be described with reference to FIGS. 32 (a) to 32 (c).
[0214]
(A) A resist 1101a is patterned on the SUS substrate 1100.
[0215]
(B) The SUS substrate 1100 on which the resist 1101 is patterned is immersed in an etching solution (an aqueous solution of ferric chloride or cupric chloride), and a portion exposed from the resist 1101a is etched by 5 μm. Thereafter, the resist 1101a is peeled off.
[0216]
(C) The resist 1101b is applied again to the entire etched surface of the SUS substrate 1100.
[0217]
(D) The resist 1101b applied in the above process is patterned by exposure so that the resist 110b remains only at the bottom of the etched portion of the SUS substrate 1100.
[0218]
(E) Using the SUS substrate 1100 as described above as a base material, the SUS substrate 1100 is electroplated to grow a nickel layer 1102 on the SUS substrate 1100 by 5 μm. As a plating solution, a stress reducing agent (manufactured by World Metal: Zeolol), boric acid, a pit preventing agent (manufactured by World Metal: NP-APS), and nickel chloride were used for nickel sulfamate. The method of applying an electric field during electrodeposition is to attach an electrode on the anode side, attach a SUS substrate 1100 already patterned with a resist 1101b on the cathode side, set the temperature of the plating solution to 50 ° C., and set the current density to 5 A / cm. ² It was.
[0219]
(F) Movable ultrasonic vibration is applied to the SUS substrate 1100 that has been plated as described above, the nickel layer 1102 is peeled off from the SUS substrate 1100, and the elevation portions are integrally provided at both ends in the width direction. The member 31 is obtained.
[0220]
<Manufacture of liquid discharge head>
Next, the manufacturing process of the liquid discharge head of the present invention will be described.
[0221]
In the case of the liquid discharge head as shown in FIG. 2, a base 34 for providing the movable member 31 is formed on the element substrate 1 by patterning a dry film or the like. The movable member 31 formed in this manner was bonded or fixed by welding. Thereafter, a grooved member having a plurality of grooves constituting each liquid flow path 10, a discharge port 18 and a concave part constituting a common liquid chamber 13 is joined to the element substrate 1 in a state where the groove and the movable member 31 correspond to each other To form.
[0222]
Next, a manufacturing process of a liquid discharge head having a two-channel structure as shown in FIGS. 14 and 28 will be described.
[0223]
Roughly, a wall of the second liquid channel 16 is formed on the element substrate 1, a separation wall 30 having a movable member 31 is attached thereon, and a groove constituting the first liquid channel 14 is further formed thereon. The grooved member 50 provided with the like is attached. Or after forming the wall of the 2nd liquid flow path 16, the head was manufactured by joining the grooved member 50 which attached the separation wall 30 on this wall.
[0224]
Further, a method for producing the second liquid channel 16 will be described in detail.
[0225]
33 (a) to 33 (e) are schematic cross-sectional views for explaining an example of the manufacturing method of the liquid discharge head of the present invention.
[0226]
In this example, as shown in (a), a heating element 2 made of hafnium boride, tantalum nitride or the like is used on an element substrate (silicon wafer) 1 by using a manufacturing apparatus similar to that used in the semiconductor manufacturing process. After forming the electrothermal conversion element having the above, the surface of the element substrate 1 was cleaned for the purpose of improving the adhesion to the photosensitive resin in the next step. Furthermore, in order to improve the adhesion, the surface of the element substrate 1 is subjected to surface modification by ultraviolet-ozone or the like, and then, for example, a silane coupling agent (manufactured by Nippon Unica: A189) is diluted to 1% by weight with ethyl alcohol. This is achieved by spin-coating the resulting solution on the modified surface.
[0227]
Next, surface cleaning was performed, and an ultraviolet-sensitive resin film (manufactured by Tokyo Ohka: dry film OD-318) DF was laminated on the element substrate 1 with improved adhesion as shown in FIG.
[0228]
Next, as shown in (c), a photomask PM was placed on the dry film DF, and ultraviolet light was irradiated to the portion of the dry film DF left as the second flow path wall through the photomask PM. This exposure process is performed using Canon Inc .: MPA-600, and is about 600 mJ / cm. ² The exposure amount was.
[0229]
Next, as shown in (d), the dry film DF is developed with a developer (Tokyo Ohka: BMRC-3) made of a mixed solution of xylene and butyl cellosolve acetate, and the unexposed part is dissolved. The exposed and cured part was formed as a wall part of the second liquid channel 16. Further, the residue remaining on the surface of the element substrate 1 is removed by treating with an oxygen plasma ashing apparatus (manufactured by Alcantech Co., Ltd .: MAS-800) for about 90 seconds, then at 150 ° C. for 2 hours and further with ultraviolet irradiation of 100 mJ / cm. ² To completely cure the exposed portion.
[0230]
By the above method, the second liquid flow path 16 can be uniformly formed with respect to a plurality of heater boards (element substrates) divided and manufactured from the silicon substrate. The silicon substrate was cut and separated into each heater board 1 with a dicing machine (Tokyo Seimitsu: AWD-4000) equipped with a diamond blade having a thickness of 0.05 mm. The separated heater board 1 was fixed on an aluminum base plate (support) 70 with an adhesive (manufactured by Toray: SE4400) (FIG. 36). Subsequently, the printed wiring board 73 (FIG. 36) previously joined on the aluminum base plate 70 and the heater board 1 were connected by an aluminum wire (not shown) having a diameter of 0.05 mm.
[0231]
Next, as shown in FIG. 33 (e), the joined body of the grooved member 50 and the separation wall 30 was positioned and joined to the heater board 1 obtained in this way, as shown in FIG. That is, the grooved member 50 having the separation wall 30 and the heater board 1 are positioned and engaged and fixed by the holding spring 78 (FIG. 36), and then the ink / foaming liquid supply member 80 (FIG. 36) is attached to the aluminum base plate. 70, and the gap between the aluminum wire, the grooved member 50, the heater board 1, and the ink / foaming liquid supply member 80 was sealed with a silicone sealant (Toshiba Silicone: TSE399) to complete.
[0232]
By forming the second liquid channel 16 by the above manufacturing method, it is possible to obtain a highly accurate channel with no positional deviation with respect to each heating element 2 of each heater board 1. In particular, the positional accuracy of the first liquid flow path 14 and the movable member 31 can be increased by previously joining the grooved member 50 and the separation wall 30 in the previous step.
[0233]
These high-precision manufacturing techniques stabilize the discharge and improve the print quality. Further, since it can be formed on the wafer in a lump, it can be manufactured in large quantities at a low cost.
[0234]
In this example, an ultraviolet curable dry film was used to form the second liquid flow path 16. However, a resin having an absorption band in the ultraviolet region, particularly around 248 nm, was laminated, cured, and excimer. It can also be obtained by directly removing the resin of the portion that becomes the second liquid flow path 16 with a laser.
[0235]
34A to 34D are schematic cross-sectional views for explaining another example of the method of manufacturing the liquid ejection head of the present invention.
[0236]
In this example, as shown in (a), a resist 101 having a thickness of 15 μm was patterned on the SUS substrate 1100 in the shape of the second liquid channel.
[0237]
Next, as shown in (b), electroplating was performed on the SUS substrate 1100 to grow a nickel layer 1102 on the SUS substrate 1100 by 15 μm. As a plating solution, a stress reducer (manufactured by World Metal: Zerool), boric acid, a pit inhibitor (manufactured by World Metal: NP-APS), and nickel chloride were used as nickel sulfamate. The method of applying an electric field during electrodeposition is to attach an electrode on the anode side, attach an already patterned SUS substrate 1100 to the cathode side, set the temperature of the plating solution to 50 ° C., and set the current density to 5 A / cm. ² It was.
[0238]
Next, as shown in (c), ultrasonic vibration is applied to the SUS substrate 1100 that has been plated as described above, and a portion of the nickel layer 1102 is peeled off from the SUS substrate 1100, and a desired second liquid flow path is obtained. Got.
[0239]
On the other hand, a heater board provided with an electrothermal conversion element was formed on a silicon wafer using a manufacturing apparatus similar to a semiconductor. This wafer was separated into each heater board by a dicing machine as in the previous example. The heater board 1 was bonded to an aluminum base plate 70 to which a printed wiring board 73 was previously bonded, and an electrical wiring was formed by connecting the printed wiring board 73 and an aluminum wire (not shown). On the heater board 1 in such a state, as shown in FIG. 34 (d), the second liquid channel 16 obtained in the previous step was positioned and fixed. At the time of this fixing, since the grooved member that fixes the separation wall and the pressing spring are engaged and brought into close contact with each other as in the example described with reference to FIG. 33, no positional deviation occurs when the grooved member is joined. It is sufficient if it is fixed to the extent.
[0240]
In this example, an ultraviolet curable adhesive (Grace Japan: Amicon UV-300) is applied to the positioning and fixing, and an ultraviolet irradiation device is used, and an exposure amount is 100 mJ / cm. ² Fixing was completed in about 3 seconds.
[0241]
According to the manufacturing method of the present example, in addition to being able to obtain the second liquid flow path 16 with high accuracy without positional deviation with respect to the heating element 2, since the flow path wall is formed of nickel, the alkaline liquid It is possible to provide a head that is strong and reliable.
[0242]
FIGS. 35A to 35D are schematic cross-sectional views for explaining still another example of the method for manufacturing a liquid discharge head according to the present invention.
[0243]
In this example, as shown in (a), a resist 1103 was applied to both surfaces of an alignment hole 1100a or a SUS substrate 1100 having a thickness of 15 μm. Here, PMERP-AR900 manufactured by Tokyo Ohka was used as the resist 1103.
[0244]
Thereafter, as shown in (b), exposure is performed using an exposure apparatus (manufactured by Canon Inc .: MPA-600) in accordance with the alignment hole 1100a of the SUS substrate 1100 to form the second liquid flow path. Part of the resist 1103 was removed. Exposure is 800mJ / cm ² The exposure amount was.
[0245]
Next, as shown in (c), the SUS substrate 1100 on which the resists 1103 on both sides are patterned is immersed in an etching solution (an aqueous solution of ferric chloride or cupric chloride) and exposed from the resist 1103. After etching the portion, the resist 1103 was peeled off.
[0246]
Next, as shown in (d), as in the example of the previous manufacturing method, the liquid discharge head having the second liquid flow path 16 is formed by positioning and fixing the etched SUS substrate 1100 on the heater board 1. Assembled.
[0247]
According to the manufacturing method of this example, in addition to being able to obtain the second liquid flow path 16 with high accuracy without positional deviation with respect to the heating element 2, since the flow path is formed of SUS, acid or alkaline liquid It is possible to provide a liquid ejection head that is strong and reliable.
[0248]
As described above, according to the manufacturing method of this example, the heating element and the second liquid flow path can be positioned with high accuracy by arranging the wall of the second liquid flow path in advance in the element substrate shape. Is possible. In addition, since the second liquid flow path can be formed simultaneously on a large number of element substrates on the substrate before cutting and separation, a large amount and a low cost liquid discharge head can be provided.
[0249]
Further, in the liquid discharge head obtained by the manufacturing method of this example, since the heating element and the second liquid channel are positioned with high accuracy, the pressure of foaming due to heat generation of the electrothermal transducer is efficiently received. And the discharge efficiency is excellent.
[0250]
<Liquid discharge head cartridge>
Next, a liquid discharge head cartridge equipped with the liquid discharge head according to the above embodiment will be schematically described.
[0251]
FIG. 36 is a schematic exploded perspective view of a liquid discharge head cartridge including the liquid discharge head described above. The liquid discharge head cartridge is mainly composed of a liquid discharge head portion 200 and a liquid container 90.
[0252]
The liquid discharge head unit 200 includes the element substrate 1, the separation wall 30, a grooved member 50, a holding spring 78, a liquid supply member 80, an aluminum base plate (support) 70, and the like. The element substrate 1 is provided with a plurality of heating resistors for applying heat to the foaming liquid as described above, and a functional element for selectively driving the heating resistors. Are provided. A foaming liquid path is formed between the element substrate 1 and the aforementioned separation wall 30 having the movable wall, and the foaming liquid flows. By joining the separation wall 30 and the grooved member 50, a discharge flow path (not shown) through which discharged discharge liquid flows is formed.
[0253]
The holding spring 78 is a member that applies a biasing force in the direction of the element substrate 1 to the grooved member 50, and the biasing force causes the element substrate 1, the separation wall 30, the grooved member 50, and a support body 70 to be described later. It is well integrated.
[0254]
The support 70 is for supporting the element substrate 1 and the like. The support 70 is further connected to the element substrate 1 and connected to the printed wiring board 73 for supplying an electric signal and the apparatus side. Thus, contact pads 74 for exchanging electrical signals with the apparatus side are arranged.
[0255]
The liquid container 90 separately stores therein a discharge liquid such as ink and a foaming liquid for generating bubbles, which are supplied to the liquid discharge head unit 200. On the outside of the liquid container 90, a positioning part 94 for arranging a connection member for connecting the liquid ejection head part 200 and the liquid container 90 and a fixed shaft 95 for fixing the connection member are provided. The supply of the discharge liquid is supplied from the discharge liquid supply path 92 of the liquid container 90 to the discharge liquid supply path 81 of the liquid supply member 80 through the connection member supply path 84, and the liquid supply paths 83, 79, 20 of each member. To be supplied to the first common liquid chamber. Similarly, the foaming liquid is supplied from the foaming liquid supply path 93 of the liquid container 90 to the foaming liquid supply path 82 of the liquid supply member 80 via the supply path of the connection member, and the liquid supply paths 84, 79, and 21 of the respective members are supplied. Through the second liquid chamber.
[0256]
In the above liquid discharge head cartridge, the description has been given with respect to the supply mode and the liquid container 90 that can supply the foam liquid and the discharge liquid even when the foam liquid and the discharge liquid are different, but in the case where the discharge liquid and the foam liquid are the same The supply path and the container for the foaming liquid and the discharge liquid need not be separated.
[0257]
The liquid container 90 may be refilled and used after consumption of each liquid. For this purpose, it is desirable to provide a liquid inlet in the liquid container 90. Further, the liquid discharge head unit 200 and the liquid container 90 may be integrated or separable.
[0258]
<Liquid ejection device>
FIG. 37 shows a schematic configuration of a liquid discharge apparatus equipped with the above-described liquid discharge head. In this embodiment, an ink discharge recording apparatus IJRA using ink as the discharge liquid will be described in particular. The carriage HC of the liquid ejection apparatus is equipped with a head cartridge in which a liquid container 90 for storing ink and a liquid ejection head unit 200 can be attached and detached, and a recording medium such as recording paper conveyed by a recording medium conveyance unit. It reciprocates in the 150 width direction (arrow a, b direction).
[0259]
When a drive signal is supplied from a drive signal supply unit (not shown) to the liquid discharge unit on the carriage HC, the recording liquid is discharged from the liquid discharge head unit 200 to the recording medium 150 in response to this signal.
[0260]
In the liquid ejection apparatus according to the present embodiment, the motor 111 as a drive source for driving the recording medium transport unit and the carriage HC, gears 112 and 113 for transmitting the power from the drive source to the carriage HC, and It has a carriage shaft 85 and the like. With this recording apparatus and the liquid ejection method performed by this recording apparatus, it was possible to obtain recorded images with good images by ejecting liquid onto various recording media.
[0261]
FIG. 38 is a block diagram of the entire apparatus for operating the ink discharge recording apparatus to which the liquid discharge head of the present invention is applied.
[0262]
The recording apparatus receives print information from the host computer 300 as a control signal. The print information is temporarily stored in the input / output interface 301 in the printing apparatus, and at the same time, converted into data that can be processed in the recording apparatus, and input to the CPU 302 that also serves as a head drive signal supply unit. Based on a control program stored in the ROM 303, the CPU 302 processes the data input to the CPU 302 using a peripheral unit such as the RAM 304 and converts it into data (image data) to be printed.
[0263]
In order to record the image data at an appropriate position on the recording paper, the CPU 302 generates drive data for driving the drive motor 306 that moves the recording paper and the head 200 in synchronization with the image data. The image data and the motor drive data are transmitted to the head 200 and the drive motor 306 via the head driver 307 and the motor driver 305, respectively, and are driven at controlled timings to form an image.
[0264]
The recording medium that can be applied to the recording apparatus as described above and to which liquid such as ink is applied includes various papers, OHP sheets, plastic materials used for compact discs, decorative plates, etc., fabrics, aluminum, copper, etc. Metal materials, leather materials such as cowhide, pig skin, and artificial leather, wood such as wood and plywood, ceramic materials such as bamboo and tiles, and three-dimensional structures such as sponges can be targeted.
[0265]
Further, as the above-mentioned recording apparatus, a printer apparatus that records on various papers and OHP sheets, a recording apparatus for plastic that records on a plastic material such as a compact disk, a recording apparatus for metal that records on a metal plate, leather For recording apparatus for leather, recording apparatus for wood for recording on wood, recording apparatus for ceramics for recording on ceramic material, recording apparatus for recording on three-dimensional network structure such as sponge, and fabric It also includes a textile printing apparatus that performs recording.
[0266]
In addition, as a discharge liquid used in these liquid discharge apparatuses, a liquid suitable for each recording medium and recording conditions may be used.
[0267]
<Recording system>
Next, an example of an ink jet recording system that performs recording on a recording medium using the liquid discharge head of the present invention as a recording head will be described.
[0268]
FIG. 39 is a schematic diagram for explaining the configuration of an ink jet recording system using the above-described liquid discharge head of the present invention. The liquid discharge head in this embodiment is a full-line type head in which a plurality of discharge ports are arranged at a distance corresponding to 360 dpi in a length corresponding to the recordable width of the recording medium 150, and is yellow (Y), magenta (M). , Cyan (C) and black (Bk), four heads 201a to 201d are fixed and supported in parallel with each other at a predetermined interval in the X direction by a holder 202.
[0269]
A signal is supplied to each of these heads 201a to 201d from a head driver 307 constituting drive signal supply means, and the heads 201a to 201d are driven based on this signal.
[0270]
Each of the heads 201a to 201d is supplied with inks of four colors Y, M, C, and Bk from the ink containers 204a to 204d, respectively. Reference numeral 204e denotes a foaming liquid container in which the foaming liquid is stored, and the foaming liquid is supplied from the foaming liquid container 204e to each of the heads 201a to 201d.
[0271]
Further, below the heads 201a to 201d, there are provided head caps 203a to 203d in which ink absorbing members such as sponges are arranged, and by covering the ejection openings of the heads 201a to 201d during non-recording. Maintenance of the heads 201a to 201d can be performed.
[0272]
Reference numeral 206 denotes a conveying belt that constitutes conveying means for conveying various non-recording media as described in the previous embodiments. The conveyor belt 206 is drawn around a predetermined path by various rollers, and is driven by a driving roller connected to a motor driver 305.
[0273]
In the ink jet recording system of this embodiment, a pre-processing device 251 and a post-processing device 252 that perform various processes on the recording medium before and after recording are provided upstream and downstream of the recording medium conveyance path, respectively. .
[0274]
The pre-processing and post-processing differ depending on the type of recording medium to be recorded and the type of ink. For example, for recording media such as metal, plastic, ceramics, etc. Ink adhesion can be improved by irradiating ultraviolet rays and ozone and activating the surface. Further, in a recording medium such as plastic that easily generates static electricity, dust is likely to adhere to the surface due to static electricity, and good recording may be hindered by the dust. For this reason, it is preferable to remove dust from the recording medium by removing static electricity from the recording medium using an ionizer device as pretreatment. When a fabric is used as a recording medium, the fabric is selected from alkaline materials, water-soluble materials, synthetic polymers, water-soluble metal salts, urea and thiourea from the viewpoint of preventing bleeding and improving the dyeing rate. The treatment for applying the substance may be performed as a pretreatment. The preprocessing is not limited to these, and may be a process for setting the temperature of the recording medium to an appropriate temperature for recording.
[0275]
On the other hand, post-processing includes a fixing process that promotes fixing of the ink by heat treatment, ultraviolet irradiation, etc., on the recording medium to which the ink has been applied, a process of washing the unreacted processing agent that has been applied in the pre-process Is to do.
[0276]
In this embodiment, the full line head is used as the heads 201a to 201d. However, the present invention is not limited to this, and recording is performed by transporting a small head as described above in the width direction of the recording medium. It may be a thing.
[0277]
<Head kit>
Below, the head kit which has the liquid discharge head of this invention is demonstrated. FIG. 40 is a schematic view showing such a head kit. The head kit 500 includes a head 510 of the present invention having an ink discharge portion 511 that discharges ink, an ink container 520 that is a liquid container that is inseparable from or separable from the head 510, and the ink container 520 is filled with ink. The ink filling means 530 holding the ink for storing is contained in the kit container 501.
[0278]
When the ink is consumed, the insertion portion (injection needle) of the ink filling means 530 is inserted into a connection portion between the air communication port 521 of the ink container 520 and the head 510 or a hole formed in the wall of the ink container 520. Etc.) A part of 531 may be inserted, and the ink in the ink filling means 530 may be filled into the ink container 520 through the insertion portion 531.
[0279]
In this way, by placing the head 510 of the present invention, the ink container 520, the ink filling means 530, etc. in one kit container 501, a kit can be used as described above even if the ink is consumed. Ink can be easily filled into the ink container 520, and recording can be started quickly.
[0280]
The head kit 500 of the present embodiment has been described as including the ink filling means 530. However, the head kit does not have the ink filling means and is a separable type ink container filled with ink. The head may be stored in the kit container 510.
[0281]
FIG. 40 shows only the ink filling means 530 that fills the ink container 520 with ink, but in addition to the ink container 520, the foam liquid filling means for filling the foam liquid container with the foam liquid is provided. The thing of the form stored in the kit container may be sufficient.
[0282]
The present invention is not limited to a so-called edge shooter type liquid discharge head having a discharge port at one end of the liquid flow path provided in the direction along the surface of the heating element as described above. The present invention is also applicable to a so-called side shooter type liquid discharge head having the discharge port 18 at a position facing the surface of the heating element 2.
[0283]
The side shooter type liquid discharge head shown in FIG. 41 has a foaming liquid on the element substrate 1 provided with a heating element 2 that gives thermal energy for generating bubbles in the liquid for each discharge port 18. A second liquid flow path 16 is formed, and a first liquid flow path 14 for discharge liquid directly communicating with a discharge port 18 provided in the grooved member 50 is formed on the second liquid flow path 16. The two-liquid flow path 16 is the same as the above-described edge shooter type liquid discharge head in that it is divided by a separation wall 30 made of an elastic material such as metal.
[0284]
The side shooter type liquid discharge head is characterized in that a discharge port 18 is provided in a portion directly above the heating element 2 in the grooved member (orifice plate) 50 arranged on the first liquid flow path 14. There are features. The separation wall 30 between the discharge port 18 and the heating element 2 has a pair of movable members 31 that are opened in a double door and have a width that decreases from the surface facing the heating element 2 toward the opposite surface. Is provided. Both movable members 31 have a cantilever shape supported by a fulcrum 33, and both free ends 32 are slightly separated from each other by a slit 35 located immediately below the central portion of the discharge port 18 when not discharging. And are facing each other. At the time of discharge, as shown by the arrows in FIG. 41, both movable members 31 open to the first liquid channel 14 side by foaming of the foaming liquid in the bubble generation region 11, and are closed by contraction of the foaming liquid. In this region C, the discharge liquid is refilled from a discharge liquid tank (not shown) for storing the discharge liquid and can be discharged, and can be prepared for foaming of the next foaming liquid.
[0285]
The first liquid flow path 14 communicates with the discharge liquid tank through the first common liquid chamber 15 together with the first liquid flow path 14 of the other discharge port 18, and the second liquid flow path 16 also Together with the second liquid flow path 16 of the discharge port 18, the second common liquid chamber 17 is connected to a foaming liquid tank (not shown) that stores the foaming liquid.
[0286]
In the side shooter type liquid discharge head having such a configuration, the liquid is discharged with high discharge efficiency and high discharge pressure while improving the refilling of the discharge liquid in substantially the same manner as the edge shooter type liquid discharge head. It is possible to obtain an excellent effect of being able to.
[0287]
The manufacturing method is substantially the same as that of the edge shooter type liquid discharge head except that the position of the discharge port 18 provided in the grooved member 50 is different from that of the common liquid chambers 15 and 17. The same. That is, the relationship between the separation wall 30 having the movable member 31 and the flow path wall constituting the second liquid flow path 16 is the same for both.
[0288]
Further, in each of the above-described embodiments, the example in which the resistance to the liquid at the time of displacement is reduced depending on the shape of the movable member is shown. However, the contact angle of the liquid on the surface opposite to the surface facing the heating element is set to generate heat. The resistance to the liquid at the time of displacement can also be reduced by performing processing on the movable member so as to make it smaller than that of the surface facing the body.
[0289]
【The invention's effect】
As mentioned above, From the first position in the steady state to the second position after the displacement The liquid in the flow path when displaced versus According to the liquid discharge head of the present invention that uses a movable member with reduced resistance and displaces the movable member by pressure based on the generation of bubbles and guides the liquid to the discharge port side, the movable member is easily displaced, and the discharge efficiency and The discharge force can be further improved. Furthermore, by making the surface facing the heating element of the movable member flat or by making the both ends of the width direction protrude toward the heating element rather than the central part, the movable member is likely to receive pressure components of bubbles, Or it becomes difficult to escape and the pressure based on generation | occurrence | production of a bubble can be utilized for the displacement of a movable member more effectively.
[0290]
Further, according to the characteristic configuration of the present invention, it is possible to prevent non-ejection even when left for a long time at low temperature and low humidity, and recovery such as preliminary ejection and suction recovery even if non-ejection occurs. There is also an advantage that the normal state can be instantly restored with a small amount of processing. Accordingly, the recovery time can be shortened, the liquid loss due to the recovery can be reduced, and the running cost can be greatly reduced.
[0291]
In particular, according to the configuration with improved refill characteristics of the present invention, it is possible to achieve high-speed recording or high-quality recording by high-speed liquid ejection by achieving responsiveness during continuous ejection, stable bubble growth, and droplet stabilization. I was able to.
[0292]
In addition, by using a liquid that easily foams or a liquid that does not easily generate deposits (burning, etc.) on the heating element as a foaming liquid in a head having a two-channel configuration, the degree of freedom in selecting a discharge liquid increases. Liquids that were difficult to be ejected by conventional bubble jet ejection methods, such as highly viscous liquids that are less prone to foaming and liquids that tend to cause deposits on the heating element, could be satisfactorily ejected.
[0293]
Furthermore, liquids that are vulnerable to heat could be discharged without adversely affecting the liquids.
[0294]
Further, by using the liquid discharge head of the present invention as a recording liquid discharge recording head, it was possible to achieve recording with higher image quality.
[0295]
In addition, it was possible to provide a liquid ejection apparatus, a recording system, and the like that further improved the liquid ejection efficiency using the liquid ejection head of the present invention.
[Brief description of the drawings]
FIG. 1 is a schematic cross-sectional view showing an example of a liquid discharge head of the present invention.
FIG. 2 is a partially broken perspective view of the liquid discharge head shown in FIG.
3 is a schematic cross-sectional view of the liquid discharge head shown in FIG. 1 as viewed from the discharge port direction.
FIG. 4 is a schematic diagram showing pressure propagation from bubbles in a conventional head.
FIG. 5 is a schematic diagram showing pressure propagation from bubbles in the liquid ejection head of the present invention.
6 is a schematic diagram for explaining the flow of liquid in the liquid discharge head shown in FIG. 1. FIG.
FIG. 7 is a schematic cross-sectional view of a liquid discharge head in a second embodiment of the present invention.
8 is a schematic cross-sectional view of the liquid discharge head shown in FIG. 7 as viewed from the discharge port direction.
FIG. 9 is a schematic cross-sectional view of a liquid discharge head according to a third embodiment of the present invention.
FIG. 10 is a partially broken perspective view of a liquid discharge head according to a fourth embodiment of the present invention.
FIG. 11 is a partially broken perspective view of a liquid discharge head according to a fifth embodiment of the present invention.
FIG. 12 is a cross-sectional view of a liquid discharge head according to a sixth embodiment of the present invention.
FIG. 13 is a schematic cross-sectional view of a liquid discharge head according to a seventh embodiment of the present invention.
FIG. 14 is a cross-sectional view of a liquid discharge head (two flow paths) in an eighth embodiment of the present invention.
15 is a partially broken perspective view of the liquid discharge head shown in FIG.
FIG. 16 is a diagram for explaining the operation of the movable member.
FIG. 17 is a cross-sectional view showing various modifications (a) to (i) of the movable member.
FIG. 18 is a diagram for explaining another example of the ceiling shape of the first liquid channel.
FIG. 19 is a diagram for explaining an arrangement relationship between a second liquid channel and a movable member.
FIG. 20 is a view for explaining another shape of the movable member.
FIG. 21 is a graph showing the relationship between the heating element area and the ink discharge amount.
FIG. 22 is a diagram illustrating an arrangement relationship between a movable member and a heating element.
FIG. 23 is a graph showing the relationship between the distance between the edge of the heating element and the fulcrum and the amount of displacement of the movable member.
FIG. 24 is a diagram for explaining an arrangement relationship between a heating element and a movable member.
FIG. 25 is a longitudinal sectional view of a liquid discharge head according to the present invention.
FIG. 26 is a schematic diagram showing the shape of a drive pulse.
FIG. 27 is a cross-sectional view for explaining a supply path of the liquid ejection head of the present invention.
FIG. 28 is an exploded perspective view of the head of the present invention.
FIG. 29 is a process diagram for describing the manufacturing method of the movable member shown in FIG. 3;
30 is a process diagram for describing a method of manufacturing the movable member shown in FIG.
FIG. 31 is a process diagram for describing a method of manufacturing the movable member shown in FIG.
FIG. 32 is a process diagram for describing the manufacturing method for the movable member shown in FIG.
FIG. 33 is a process diagram for describing the manufacturing method for the liquid ejection head according to the present invention.
FIG. 34 is a process diagram for describing the manufacturing method of the liquid ejection head of the present invention.
FIG. 35 is a process diagram for describing the manufacturing method of the liquid ejection head of the present invention.
FIG. 36 is an exploded perspective view of the liquid discharge head cartridge.
FIG. 37 is a schematic configuration diagram of a liquid ejection apparatus.
FIG. 38 is a device block diagram.
FIG. 39 is a diagram illustrating a liquid discharge recording system.
FIG. 40 is a schematic diagram of a head kit.
FIG. 41 is a cross-sectional view of an example of a side shooter type liquid discharge head to which the present invention is applied.
FIG. 42 is a diagram for explaining a liquid flow path structure of a conventional liquid discharge head.
[Explanation of symbols]
1 Element substrate
2 Heating element
3 Area center
10 Liquid flow path
11 Bubble generation area
12 Supply path
13 Common liquid chamber
14 First liquid flow path
15 First common liquid chamber
16 Second liquid flow path
17 Second common liquid chamber
18 Discharge port
19 Stenosis
20 First supply path
21 Second supply path
22 First liquid channel wall
23 Second liquid flow path wall
24 Convex
30 separation wall
31 Movable member
31a Elevation
32 Free end
33 fulcrum
34 Support members
35 slits
36 Front wall of bubble generation area
37 Side wall of bubble generation area
40 bubbles
50 Grooved member
70 Support
78 Presser spring
80 Supply members

Claims (31)

A discharge port for discharging liquid;
A liquid flow path communicating with the discharge port;
A bubble generation region for generating bubbles in the liquid in the liquid flow path;
Displaced from the first position in the steady state to the second position after being displaced by the pressure based on the generation of bubbles in the bubble generation region. And a movable member that guides the pressure to the downstream side where the discharge port is disposed by this displacement, and returns to the first position by a negative pressure due to contraction of bubbles,
The movable member has a resistance to the liquid in the flow path when the movable member is displaced from the first position to the second position, more than a resistance when the movable member returns from the second position to the first position. Small liquid discharge head. A discharge port for discharging liquid;
A first liquid flow path communicating with the discharge port;
A second liquid flow path having a bubble generation region for generating bubbles in the liquid by applying heat to the liquid;
The first liquid is disposed between the first liquid flow path and the bubble generation region, and is a position after displacement from the first position in a steady state by pressure based on generation of bubbles in the bubble generation region. A movable member that is displaced to a second position on the liquid flow path side, guides the pressure to the downstream side where the discharge port is disposed by this displacement, and returns to the first position by negative pressure due to contraction of bubbles. And
When the movable member is displaced from the first position to the second position, the resistance to the liquid in the first liquid flow path returns from the second position to the first position. The liquid discharge head is smaller than the resistance.   The liquid ejecting head according to claim 2, wherein the movable member is configured as a part of a separation wall disposed between the first liquid channel and the second liquid channel.   A first common liquid chamber for supplying a first liquid to a plurality of the first liquid flow paths and a second common for supplying a second liquid to a plurality of the second liquid flow paths The liquid discharge head according to claim 2, wherein a liquid chamber is arranged.   The liquid discharge head according to claim 1, wherein a heating element is provided at a position facing the movable member, and the bubble generation region is between the movable member and the heating element. A plurality of outlets for discharging liquid;
A plurality of grooves for configuring a plurality of first liquid flow paths that directly communicate with each discharge port;
A grooved member integrally having a concave portion constituting a first common liquid chamber for supplying a liquid to the plurality of first liquid flow paths;
An element substrate provided with a plurality of heating elements for generating bubbles in the liquid by applying heat to the liquid;
The bubble is generated between the grooved member and the element substrate, forming a part of the wall of the second liquid flow path corresponding to the heating element, and at a position facing the heating element. Is displaced from the first position in the steady state to the second position on the first liquid flow path side, which is the position after displacement, by this displacement, and the pressure is moved to the downstream side where the discharge port is disposed by this displacement. And a separation wall provided with a movable member that returns to the first position with a negative pressure due to the contraction of bubbles,
When the movable member is displaced from the first position to the second position, the resistance to the liquid in the first liquid flow path returns from the second position to the first position. The liquid discharge head is smaller than the resistance.   The liquid ejecting head according to claim 5, wherein the movable member is a plate-shaped member having a fulcrum and a free end located closer to the discharge port than the fulcrum.   The liquid ejection head according to claim 7, wherein the movable member has a width that decreases from a surface facing the heating element toward a surface on the opposite side.   The liquid ejection head according to claim 7, wherein a surface of the movable member that faces the heating element is a substantially flat surface.   The liquid discharge head according to claim 9, wherein a surface of the movable member that faces the heating element is parallel to a surface of the heating element.   9. The liquid ejection head according to claim 7, wherein both ends of the movable member in the width direction protrude from the central portion toward the heating element.   The liquid ejecting head according to claim 7, wherein the movable member has a thickness that decreases from the fulcrum toward the free end.   The liquid ejection head according to claim 7, wherein the movable member has a liquid contact angle on a surface opposite to the surface facing the heating element, which is smaller than a liquid contact angle on a surface facing the heating element.   The liquid discharge head according to claim 5, wherein the bubbles are bubbles generated by causing film boiling in the liquid by heat generated by the heating element.   The liquid discharge head according to claim 14, wherein a total area of the movable member is larger than a total area of the heating element.   The liquid discharge head according to claim 7, wherein a fulcrum of the movable member is disposed at a position off from directly above the heating element.   The liquid discharge head according to claim 7, wherein the free end of the movable member has a shape substantially orthogonal to a liquid flow path in which the heating element is disposed.   The liquid discharge head according to claim 7, wherein the free end of the movable member is located downstream of the flow of the liquid toward the discharge port in the liquid flow channel with respect to the area center of the heating element.   The grooved member includes a first introduction path for introducing a liquid into the first common liquid chamber and a second introduction path for introducing a liquid into the second common liquid chamber. 6. A liquid discharge head according to item 6. The liquid ejection head according to claim 19 , wherein the grooved member is provided with a plurality of the second introduction paths. The liquid ejection head according to claim 19 , wherein the second introduction path is an introduction path that supplies liquid to the second common liquid chamber through the separation wall.   The liquid discharge head according to claim 5, wherein the heating element is an electrothermal converter having a heating resistor that generates heat by receiving an electrical signal. The liquid discharge head according to claim 22 , wherein the electrothermal transducer is a protective film disposed on the heating resistor. 23. The liquid according to claim 22 , wherein wiring for transmitting an electrical signal to the electrothermal transducer and a functional element for selectively providing an electrical signal to the electrothermal transducer are disposed on the element substrate. Discharge head.   A head cartridge comprising the liquid discharge head according to claim 1, and a liquid container for holding a liquid supplied to the liquid discharge head.   A liquid container that holds the liquid discharge head according to claim 3, the first liquid supplied to the first liquid flow path, and the second liquid supplied to the second liquid flow path. A head cartridge. A liquid discharge head according to claim 1, 2, or 6,
A liquid discharge apparatus comprising drive signal supply means for supplying a drive signal for discharging liquid from the liquid discharge head. A liquid discharge head according to claim 1, 2 or 6,
A liquid discharge apparatus comprising: a recording medium transport unit that transports a recording medium that receives the liquid ejected from the liquid ejection head. 29. The liquid discharge apparatus according to claim 27 or 28 , wherein recording is performed by discharging ink from the liquid discharge head and attaching the ink to a recording medium. 29. The liquid ejection apparatus according to claim 27 or 28 , wherein color recording is performed by ejecting recording liquids of a plurality of colors from the liquid ejection head and attaching the recording liquids of the plurality of colors to a recording medium. 29. The liquid ejection apparatus according to claim 27 or 28 , wherein a plurality of the ejection ports are arranged over the entire width of the recordable area of the recording medium.

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