JP3988210B2

JP3988210B2 - Recording method and recording apparatus using recording liquid

Info

Publication number: JP3988210B2
Application number: JP15119697A
Authority: JP
Inventors: 光男尾崎; 志野徳世; 重治鈴木; 裕男上田
Original assignee: Fujifilm Corp
Current assignee: Fujifilm Corp
Priority date: 1997-06-09
Filing date: 1997-06-09
Publication date: 2007-10-10
Anticipated expiration: 2017-06-09
Also published as: JPH10338830A

Description

【０００１】
【発明の属する技術分野】
本発明は、記録液を用いた記録方法に関し、より詳しく言えば、水溶性染料を色材とした第１の記録液と、着色剤により着色されておりそしてイオン性基を有する樹脂微粒子を色材とした第２の記録液とを用いて記録を行う方法及び装置に関する。
【０００２】
【従来の技術】
紙等の記録媒体に記録するのに用いられる記録液（この「記録液」は「インク」と同義と考えることができる）は、液中の色材の状態から溶解系と分散系に大別でき、また用いられる溶媒あるいは分散媒の種類から、水を含有する水性、水を含有しない溶剤性（油性）に大きく分類できる。おのおのの記録液には、それぞれ長所、短所があり、使用環境、主目的を考慮して、最適と考える記録液が選択、使用される。
【０００３】
文字や画像を記録媒体（紙やフィルム等）に記録するオフィスや個人では、取扱性の良さ、安全性、衛生上の観点から、一般に水性の記録液が使用されている。そしてこの水性記録液は、上記のとおり色材の状態を基に溶解系水性記録液と分散系水性記録液に大別される。
【０００４】
溶解系水性記録液は、一般に水溶性染料を色材とするもので、比較的高濃度で鮮やかな、良好な色の記録が可能であるという長所の反面、耐水性や耐光性が弱いという短所がある。これに対し、分散系水性記録液は、一般に顔料を色材とし、顔料の微細化に加え、表面改質あるいは界面活性剤や水溶性樹脂等の分散剤の添加により水に分散するようにしたもので、耐水性や耐光性に優れるという長所の反面、比較的安定性が低く、またくすんだ色の悪い記録になってしまうという短所がある。
【０００５】
その一方で、記録液は、記録品位の向上を目的として記録濃度の向上が望まれている。記録濃度の向上には、記録液中の色材量を増加することが有効であるが、色材量の増加は記録液の安定性を低下する傾向にあり、限界がある。特に、微細なノズルから記録液を吐出して記録を行うインクジェット記録方式等では、色材量の増加に伴い、ノズルでの色材の固体化が生じやすくなり、ドット欠け等の記録不良を招き、記録の信頼性を低下させる傾向にある。また、記録液を用いての記録では、安定で高記録品位であることが優先される。これらのことから、高彩度の必要がない黒色の記録液を除き、特にカラー記録に使用されるカラー記録液では、液の安定性に優れ、高濃度で鮮やかな記録が行える溶解系水性記録液を使用するのが主流になっている。
【０００６】
このような溶解系水性記録液を用いる際には、耐光性、耐水性の短所を解決するため、記録媒体にインク受容層を設け、このインク受容層に紫外線吸収剤、カチオン水溶性樹脂等を添加した専用記録媒体を使用することで、耐光性、耐水性の向上を図る方法が一般的である。
【０００７】
これに代わる耐光性、耐水性向上の方法として、記録媒体の記録面をフィルムで覆う方法やフィルム層を形成する方法（例えば特開昭６２−２０２７８２号公報、特開平８−２５２９８５号公報、特開平８−２５８３７２号公報など）や、記録液中に樹脂を添加する方法（例えば特開昭63−１０９０８３号公報など）が提案されている。
【０００８】
専用記録媒体を使用する方法は、効果は大きいものの、媒体が高価となる欠点を有することや、入手の簡便性、コピー等の他の記録方式との記録媒体の共通性などの課題を有しており、専用記録媒体よりもコピー等に使用される記録面に紙繊維が露呈したいわゆる普通紙の使用が要望されている。
【０００９】
また、記録媒体の記録面をフィルムで覆ったり、フィルム層を形成する方法では、記録媒体が厚くなり、取扱性が悪くなるのに加えて、記録媒体の特性である柔軟性、質感等を大きく変化させてしまう不都合があるほか、手間がかかったり、専用の装置を必要とすることもある。
【００１０】
記録液中に樹脂を添加する方法では、樹脂は水に不溶性であっても、樹脂自体は無色であり、また色材である染料を覆っていないため、記録媒体上の染料は水に溶解してしまい、耐水性は向上しないし、同様の理由で紫外線吸収剤を添加しても耐光性の向上は望めない。更には、特別な樹脂層形成手段を必要とする場合もある。
【００１１】
また、これらの方法以外に、耐光、耐水性に優れ、特にカラー記録で鮮やかな記録が可能な方法として、着色剤（染料又は顔料）で着色し且つイオン性基を含有させることで水分散可能としたポリエステル樹脂を含む記録液を用いる方法が提案されている（例えば特開平４−２９６３２１号公報、特開平７−１９６９６５号公報など）。この記録液の特徴は、色材として、水に不溶性のポリエステル樹脂を着色剤で着色して用い、特にこの着色剤を染料とすることでより鮮やかで良好な色の記録ができ、且つ良好な耐水性が得られることである。更に、ポリエステル樹脂は紫外線吸収性を有するため、また必要に応じて紫外線吸収剤を樹脂に添加することにより、良好な耐光性を得ることができる。しかし、記録濃度の向上には、樹脂を着色する着色剤濃度を増加したり、記録液中のポリエステル樹脂濃度を増加する必要があるが、樹脂に対する着色剤の溶解能には限界があり、また記録液中の樹脂濃度の増加は記録液の粘度の上昇等のように記録液の物性に大きく影響するほか、記録液の安定性を低下させる傾向もある。
【００１２】
このように、従来技術では、色材として水溶性染料を用い、あるいは特に染料で着色するとともにイオン性基を含有させて水分散可能としたポリエステル樹脂を用いることで、鮮やかで良好な色を実現できるが、耐水性、耐光性の改善には効果がなかったり、あるいは効果があっても、記録液の安定性、記録の信頼性を確保したまま記録濃度の増加等の記録品位を向上させることは実現できていない。
【００１３】
その一方で、特に近年、パソコンやアプリケーションソフトウェアの普及、性能向上により、写真やビデオデータ等のいわゆる自然画像の記録に適した、より高品位の階調カラー記録の実現の要求が強まっている。これに対して、インクジェット記録方式に代表される水性記録液を用いた記録方法では、濃淡２種類のほぼ同じ色相を有するインクを使用することで、高品位の階調記録を実現しているが、上述の耐水性、耐光性の課題は残存したままであり、新たな対策は提案されていない。
【００１４】
【発明が解決しようとする課題】
そこで、本発明は、記録液の安定性も記録の信頼性も低下させることなく、記録液を用いて記録媒体上に記録を行ったときの記録濃度が高くて、しかも耐水性、耐光性に優れた高品位の記録を実現できる記録液での記録方法の提供を目的とする。この方法を実施するための装置、及びそれで使用される記録液カートリッジを提供することも本発明の目的である。
【００１５】
【課題を解決するための手段】
本発明の記録液による記録方法は、同一色の記録液について第一及び第二の記録液を用いて記録媒体に記録を行う記録方法であって、第一の記録液として水溶性染料と水を含むものを使用し、第二の記録液として着色剤により着色されていて且つイオン性基を含有している樹脂微粒子と、この微粒子を分散させる水を含むものを使用し、そして第一の記録液で記録媒体への記録を行った後に、前記第一の記録液と同一色の第二の記録液で、記録媒体上の少なくとも第一の記録液により記録を行った部分に重ねて記録を行うことを特徴とする。
【００１６】
本発明の記録装置は、同一色の記録液について第一及び第二の記録液を用いて記録媒体に記録を行う記録装置であって、第一の記録液として水溶性染料と水を含むものを使用し、第二の記録液として着色剤により着色されていて且つイオン性基を含有している樹脂微粒子と、この微粒子を分散させる水を含むものを使用し、そして第一の記録液で記録媒体への記録を行った後に、前記第一の記録液と同一色の第二の記録液で記録媒体上の少なくとも第一の記録液により記録を行った部分に重ねて記録を行う手段を含むことを特徴とする。
【００１７】
また、本発明の記録液カートリッジは、同一色の記録液について第一及び第二の記録液を用いて記録媒体上に記録を行うためのカートリッジであって、水溶性染料及び水を含む第一の記録液と、着色剤により着色されていて且つイオン性基を含有している樹脂微粒子とこの微粒子を分散させる水を含む、前記第一の記録液と同一の第二の記録液をそれぞれ収容した容器を組み合わせて含むことを特徴とする。
【００１８】
【発明の実施の形態】
本発明では、少なくとも一つの色について第一の記録液と第二の記録液を使用する。第一の記録液は少なくとも色材としての水溶性染料と水を含み、そして第二の記録液は少なくとも、着色剤により着色されていて且つイオン性基を含有している、色材としての樹脂微粒子とこの微粒子を分散させる水を含む。言うまでもなく、第一の記録液も第二の記録液も、色材と水のほかに、筆記具やインクジェット用インクなどの通常の記録液に添加されることのある任意の添加成分を含むことができる。
【００１９】
第一の記録液で用いられる色材の水溶性染料は、水に溶解する既知の染料のうちから使用環境や使用目的に応じて任意に選ぶことができる。
【００２０】
一方、第二の記録液では、着色剤により着色されていて且つイオン性基を含有している樹脂微粒子を色材として使用する。例えば、イオン性基を有する着色したポリエステル樹脂粒子の水分散体は、平均粒径０．３μｍ程度以下で種々の粒径の水分散体が製造可能であり、且つシャープな粒度分布を有し、本発明の第二の記録液の樹脂微粒子として使用するのに好適である。このような樹脂微粒子の着色剤には、常温で水に溶解しない染料や顔料を使用できるので、色材の選択範囲が拡がり、より良好な特性の色材を使用できる。また、イオン性基には、アニオン基あるいはカチオン基のどちらも使用することができる。
【００２１】
しかし、一般に、顔料は耐水・耐光性に優れているが、カラーの場合鮮やかさが低く、色再現範囲が狭いことが、また、染料はカラーの場合鮮やかさが高く、色再現範囲が広いが、耐水・耐光性は黒色も含め顔料に劣っていることが知られている。従って、本発明の効果をより高めるには、樹脂微粒子は染料で着色し、カラーの記録液に適用することがより好ましい。すなわち、ポリエステル樹脂等の着色には染料を使用することで、より高鮮明で、色再現性の広い記録が可能となる。また、水に溶解しない染料で水に溶解しない樹脂を着色することにより、この着色樹脂を色材として使用した第二の記録液で記録を行った部分は当然耐水性が高くなり、またポリエステル等の樹脂は染料の褪色の要因である紫外線を吸収するため、第二の記録液の樹脂が記録媒体上の記録部分（すなわち記録媒体上に記録液による記録がなされる部分）の表面を覆うようにすることで、耐光性の大幅な向上が可能となる。必要に応じて紫外線吸収剤等を添加することも、耐光性の向上に寄与する。
【００２２】
このような樹脂微粒子は、例えば、イオン性基を導入したポリエステル樹脂を合成し、これを溶媒に溶解させた溶液に適当な染料を添加し溶解させた後に、水を加えて樹脂をミクロ分散体とすることで容易に製造することができる。イオン性基としては、スルホン酸アルカリ金属塩基、スルホン酸アンモニウム塩基、カルボン酸アルカリ金属塩基、カルボン酸アンモニウム塩基や、硫酸基、リン酸基、ホスホン酸基、ホスフィン酸基や、それらの酸のアンモニウム塩、金属塩等のアニオン性基や、第１級ないし第３級アミン基等のカチオン性基を導入することができる。これらの樹脂微粒子とその製造方法は、特開平４−２９６３２１号公報や特開平７−１９６９６５号公報から周知のものである。
【００２３】
本発明では、カラー記録を可能にするよう、複数の色、通常は三つの色の記録液を使用することができ、この場合、少なくとも一つの色の記録液について第一及び第二の２種類の記録液を使用し、ほかの色については１種類のみの記録液を使用することができる。このように１種類のみの記録液を用いる色については、記録液として水溶性染料及び水を含むもの（第一の記録液に相当するもの）を用いても、着色剤特に染料により着色されていて且つイオン性基を含有している樹脂微粒子とこの微粒子を分散させる水を含むもの（第二の記録液に相当するもの）を用いてもよいが、本発明の効果をより高めるため、第二の記録液に相当するものを用いる方が好ましい。また、同じ色について用いる第一及び第二の記録液は、記録媒体に記録されたときに近似したほぼ同じ色相を示すように、色相を多少異にする異なる染料と着色剤をそれぞれ使用するのが好ましい。
【００２４】
本発明の方法で記録を行う場合には、まず第一の記録液を用いて記録媒体に記録を行った後に、第二の記録液を使って記録を行うようにし、その際に記録媒体上の少なくとも第一の記録液で既に記録が行われた部分に第二の記録液を重ねるようにして記録を行う。このようにすることで、第一の記録液の記録部分表面を第二の記録液の樹脂微粒子で少なくとも部分的に覆うことにより、第二の記録液が乾く段階で樹脂の膜が形成されてその下の第一の記録液の水溶性染料を被覆するため、水性染料が水に溶けだすのが防止されるようになり、すなわち耐水性が向上する。
【００２５】
また、第二の記録液の樹脂として紫外線を吸収する性質のある例えばポリエステル樹脂の如きものを使用することで、耐光性の向上も図られる。その上、第一の記録液での記録部分の上に第二の記録液を重ねるようにすることから、高い記録濃度を要求される部分の記録についても第一の記録液及び第二の記録液の色材濃度を増加することなくその部分の記録濃度を向上でき、且つ記録液の安定性、記録の信頼性を確保できる。
【００２６】
第一及び第二の記録液の両方を用いる色の記録については、第一の記録液での記録部分の上に第二の記録部分を重ねる必要があり、両者を同時に記録することはできない。そのため、第一の記録液で記録後第二の記録液での記録を行う前に、第一の記録液が定着していることが望ましい。そこで、本発明では、少なくとも第一の記録液に浸透剤等を添加して、記録媒体への記録液の浸透を促進することで定着を速め、それにより、第一と第二の両方の記録液で同時の記録が行えないことに起因する記録速度の低下を防止できる。
【００２７】
本発明では、染料系水性記録液の特徴を生かし、同じ色について、第一の記録液を濃色の記録液として使用し、そして第二の記録液を淡色の記録液として使用して、第二の記録液を第一の記録液の記録部分に重ねて記録することで、高濃度記録部分の濃度をより向上させることができ、更に低濃度記録部分には第二の記録液を記録し、中間濃度記録部分には第一の記録液の上に第二の記録液を重ねて記録し、且つこの部分のうちの第一の記録液で記録の行われていないところに第二の記録液で記録することを組み合わせたパターンを記録し、こうして記録液の乾燥後に全ての記録部分を樹脂微粒子で少なくとも部分的に覆うことにより、耐光性、耐水性に優れ、高品位で、記録液の安定性と記録の信頼性に優れた階調記録を行うことができる。
【００２８】
更に、少なくともイエロー、マゼンタ、シアンの三色の記録液を用いて行うカラー記録では、他の二色の高濃度記録液に比べて一般に記録濃度を低く設計するイエローに第二の記録液を用い、高記録濃度と低記録濃度が必要なマゼンタ、シアンには第一の記録液と第二の記録液をそれぞれ用いることにより、耐光性、耐水性に優れ、高品位で、記録液の安定性と記録の信頼性に優れた自然画の記録に適したフルカラーの階調記録を行うことができる。この際、浸透剤等の添加により、各記録液の定着時間を、記録媒体上の色境界部分で記録液が流れ出すことに起因する混色の現象、いわゆるブリードが生じにくい程度の短時間とすることで、より高記録品位のカラー記録が可能となる。
【００２９】
【実施例】
次に、実施例により本発明を更に説明することにする。
【００３０】
〔実施例１〕
この例では、インクジェット記録方式を用い、第二の記録液の樹脂にポリエステルを使用する場合について説明する。
【００３１】
染料で着色したポリエステル樹脂微粒子の水分散体の製造方法は、特開平４−２９６３２１号公報に詳しく記載されており、特に特開平７−１９６９６５号公報にはインクジェット用の記録液（インク）の製造方法の例が記載されている。これらに記載された手順に従い、まず、下記の物質を用いて１８０〜２３０℃で１２０分間加熱することによりエステル交換反応を行い、共重合ポリエステル樹脂を製造した。
【００３２】

【００３３】
このポリエステル樹脂１００重量部と、着色剤として下記の染料
【００３４】
Ｃ．Ｉ．ＳｏｌｖｅｎｔＢｌｕｅ６４６重量部
【００３５】
と、下記の溶剤
【００３６】
メチルエチルケトン１７５重量部
テトラヒドロフラン１７５重量部
【００３７】
を混合して、樹脂、染料を溶解したのち、水６００重量部を添加して、樹脂の微粒子化を行い、これをポアサイズ０．８μｍのメンブレンフィルタで濾過、蒸留して、固形分濃度約３０重量％の平均粒径が約０．１８μｍの水分散体を得た。
【００３８】
このようにして得たシアン色の水分散体５０重量％に、湿潤剤としてグリセリン１２重量％、浸透剤としてノニオン系界面活性剤（エアプロダクツ社製サーフィノール）０．８重量％、及び水３７．２重量％を混合して、粘度約４ｃＰ、表面張力約３２ｄｙｎ／ｃｍの第二の記録液を調製した。なお、この記録液に含まれる固形分濃度は約１５重量％となった。
【００３９】
一方、水溶性染料であるＣ．Ｉ．ＡｃｉｄＢｌｕｅ９を３重量％、湿潤剤ジエチレングリコール１５重量％、浸透調整剤エチルアルコール２重量％、浸透剤ノニオン系界面活性剤（エアプロダクツ社製サーフィノール）１．０重量％、水７９重量％を混合、溶解し、ポアサイズ０．８μｍのメンブレンフィルタで濾過して、粘度約２．５ｃＰ、表面張力約３０ｄｙｎ／ｃｍの第１の記録液を調製した。
【００４０】
これらの記録液を、記録媒体にゼロックス社の普通紙ＸＥＲＯＸ４０２４ＤＰを用い、解像度３６０ｄｐｉでベタ記録（記録媒体の全面に単一濃度で行う記録）した。このとき、各記録液の定着時間を、記録媒体上に液状の記録液が残留しない時間として、記録面を紙で軽く押さえた後に記録液による汚染がその紙で観察されなくなるまでの時間を測定した結果、各記録液の定着時間は１秒未満程度であった。
【００４１】
次に、上記と同じ条件で、第一の記録液を記録した約１秒後に、この記録部分に重ねて第二の記録液を記録した。また、やはり上記と同じ条件で、最初に第二の記録液を記録した約１秒後に、この記録部分に重ねて第一の記録液を記録した。
【００４２】
このようにして得たベタ記録サンプルを１日放置した後、記録濃度（ステータスＡ濃度）と、水道水に約１分浸漬した前後での記録部分の色差（耐水性ΔＥ）、紫外線ランプで紫外線を１時間照射した前後での記録部分の色差（耐光製ΔＥ）を測定し、比較した。結果を表１に示す。
【００４３】
【表１】

【００４４】
これらの結果より、第一の記録液と第二の記録液を重ねて記録することにより記録濃度が向上することが確認できた。また、第一の記録液の上に第二の記録液を重ねて記録することで、耐光性と耐水性が向上することが確認できた。なお、この効果が、単に第二の記録液の性能によるものでないことは、第一の記録液に第二の記録液を重ねた場合の方が、第二の記録液の上に第一の記録液を重ねた場合よりも耐光性、耐水性に優れることから明らかである。
【００４５】
この効果は、第一の記録液の記録面上に第二の記録液の樹脂微粒子が付着し、記録面を少なくとも部分的に覆うためと考えられる。したがって、第一の記録液の記録面上に付着させる第二の記録液の樹脂微粒子が多いほど、より大きな効果が得られると考えられる。樹脂微粒子が多いと微粒子が結合してフィルム化させることができ、そのためより耐水性、耐光性をより向上させることができ、更に光沢性を付与することもできる。樹脂微粒子を多くするには、記録液中の樹脂量を増加する方法、記録する記録液の量を増加する方法、第二の記録液を複数回重ねて記録する方法等がある。また、フィルム化を容易にするには樹脂のガラス転移点を低くすればよいが、ガラス転移点が低くなれば樹脂微粒子の安定性が低下する傾向にあることから、記録液の温度マージン等の信頼性を考慮して設定する必要がある。なお、本実施例の樹脂では、ガラス転移点は７０℃程度であった。
【００４６】
本実施例では第一の記録液を記録してから約１秒後に第二の記録液を重ねて記録したが、より長い時間を置いて、第一の記録液での記録部を十分に乾燥させてから第二の記録液を重ねたほうが、記録表面に樹脂が残留しやすくより大きな効果が期待できる反面、記録速度は遅くなる。
【００４７】
また、本実施例では記録速度を速くするため、第二の記録液にも浸透剤を添加しているが、第一の記録液を記録してから約１秒程度以内に第二の記録液を重ねて記録する場合、第一の記録液の影響で記録媒体が湿潤しており、記録液を吸収しやすい状態となっているため、第二の記録液には浸透剤を添加しなくてもよく、むしろ記録面への樹脂の残留をより増やすためには浸透剤を添加しないほうが好ましい。
【００４８】
〔実施例２〕
次に、カラーの階調記録の場合の実施例を説明する。
【００４９】
ほぼ同じ色相で濃度の異なる記録液を使用することで、良好な階調記録が得られることが知られている。イエローは、もともとその色ゆえに他の色相の記録液よりも低温度でよく、また、濃度の異なる２種類の記録液を使用する必要のないことも知られている。そこで、ここでは前述のシアンの第一及び第二の記録液に加え、マゼンタの第一及び第二の記録液と、イエローの第二の記録液を用いてカラー階調記録を行う場合を説明する。
【００５０】
染料として、
【００５１】
Ｃ．Ｉ．ＳｏｌｖｅｎｔＹｅｌｌｏｗ１６２２０重量部
Ｃ．Ｉ．ＤｉｓｐｅｒｓｅＲｅｄ９２８重量部
【００５２】
を使用して、前述と同様の方法により、イエローとマゼンタ各色の第二の記録液を調合した。各記録液の粘度は、イエローで約３ｃＰ、マゼンタで約４ｃＰ、表面張力はともに約３２ｄｙｎ／ｃｍとなった。
【００５３】
また、染料に、
【００５４】
Ｃ．Ｉ．ＡｃｉｄＲｅｄ２４９４重量％
【００５５】
を使用して、前述と同様の方法により、マゼンタの第一の記録液を調合した。この記録液の粘度は約２．５ｃＰ、表面張力は約３０ｄｙｎ／ｃｍとなった。
【００５６】
カラー記録の場合、記録液の定着時間が遅く、記録媒体表面で色の異なる液状の記録液が接触すると記録液が拡散、流れ出し、混色して、いわゆるブリードを発現し、記録品位を低下させる。本実施例では、このブリードを低減、防止するため、各記録液に浸透剤を添加して、記録液を速やかに記録媒体内に吸収させることで定着時間を短くし、ブリードを低減している。しかし、第二の記録液、特に低濃度のマゼンタやシアンが単独記録される部分は、ハイライト部分と呼ばれる記録密度の低い部分であるため、多量の記録液が記録されることはなく、その結果異なる色相の記録液が接触してブリードを生じることが少ない。従って、第二の記録液のマゼンタ、シアンには浸透剤を添加しなくてもよく、また添加しても他の記録液よりも量を少なくできる。
【００５７】
記録装置としては、このように調合した第一及び第二の記録液を使用し、第一の記録液での記録後に第二の記録液で記録を行える種々のものが使用できるが、特にインクジェットプリンタでは、図１に示す構成を例として挙げることができる。このような構成によれば、記録速度の低下を伴わずに、本発明を実現でき、高品位で耐水性と耐光性がともに高い階調記録が実現できる。
【００５８】
図１に示したシリアルタイプのカラーインクジェットプリンタ４０は、記録液を吐出するノズルを有する記録ヘッド（図示せず）と記録液を保持したインクカートリッジ４５が接続、一体化されて、矢印Ｘの主走査方向に移動するキャリア４２に搭載されている。記録媒体の紙５０は、紙送りローラ４４により矢印Ｙの副走査方向に搬送される。
【００５９】
記録ヘッド部は、記録液を吐出するノズルのあるノズル面が記録媒体に対向した位置にあり、ステーシャフト４３をガイドとして、矢印Ｘの主走査方向に往復移動して記録液を画像データに基づき吐出することにより記録媒体上にドットを形成する。一方、記録媒体である紙５０は、記録ヘッド部の１走査により記録された記録幅に対応して、副走査方向Ｙに所定距離移動する。この基本動作の繰り返しにより、ドットにより構成された画像を記録する。
【００６０】
図２は、各記録液に対応した記録ヘッドの配置の一例を示している。すなわち、主走査方向Ｘに平行に、第一の記録液のマゼンタ、シアンに対応した二つの記録ヘッド６１、６２を配置して記録ヘッド列Ａを設け、そして第二の記録液のイエロー、マゼンタ、シアンに対応した三つの記録ヘッド６５、６６、６７を配置して記録ヘッド列Ｂを設けている。各記録ヘッドには、各記録液を吐出するのに用いられる所定の数のノズル６８が設けられている。この図に示したヘッドの配列を採用した記録ヘッド部の場合、記録媒体上の同一の位置に対して記録ヘッド列Ａによる記録が記録ヘッド列Ｂによる記録よりも先に行われるよう、副走査方向Ｙに平行に、記録ヘッド列Ａが先頭となるように記録ヘッド列Ａと記録ヘッド列Ｂを配置して、記録ヘッド部を構成する。このようにヘッド部を構成することで、記録媒体上で第一の記録液と第二の記録液を重ねて記録する場合、かならず第一の記録液が先に記録される。更に、記録の解像度やノズルから吐出する記録液の吐出最高周波数、記録幅等に依存するものの、１副走査分の時間を経過してから第二のインクを重ねて記録できることになり、記録装置の記録速度内で、かつ第一の記録液による記録後第二の記録液を記録するまでの時間を長くとって本発明を実現できることから、記録速度を低下させることなく、高速でより効果が大きい記録を実現できる。
【００６１】
記録ヘッド部のもう一つの例として、第一の記録液に対応した複数の記録ヘッドを主走査方向Ｘに平行に配置し、そして第二の記録液に対応した複数の記録ヘッドを第一の記録液に対応した記録ヘッドの列に続けてやはり主走査方向Ｘに平行に配置して、各記録液に対応したヘッドが一列に並んだ構成のものを挙げることができる。この場合には、この記録ヘッド部を往復走査して記録を行うときに、往路で第一の記録液を、これに続く復路で第二の記録液を記録することで、記録速度の低下なしに本発明を実施できる。
【００６２】
図１で概説した装置で、図２により説明した記録ヘッドの配列を採用したカートリッジを使って、７２０ｄｐｉの解像度、記録液の最高吐出周波数７ｋＨｚで階調記録を行った結果、高記録濃度で、耐光性、耐水性が改善された高記録品位の階調画像を得ることができた。
【００６３】
本実施例では、イエロー、マゼンタ、シアンの３色を用いて記録を行ったが、これらの３色の記録液に黒色の記録液を加えて、４色の記録液で記録を行うこともできる。この場合、黒色の記録液は、公知の染料系や、耐光性、耐水性に優れたカーボンブラック等の顔料を分散した分散系、更には本発明における第二の記録液、あるいは本発明による第一と第二の記録液の組み合わせを使用することができる。しかし、本発明の効果をより大きなものとするには、顔料分散系の記録液の如く、耐水性、耐光性に優れたものを使用することが好ましい。
【００６４】
また、記録液の製造方法、構成物質等についても、種々のものが使用可能であり、上記の例に限定されるものではない。更に、記録装置や記録液の容器（カートリッジ）も種々のものが使用可能であり、上記の例に限定されないことは言うまでもない。また、各記録液の量（カートリッジの容量）も、主に記録する画像データに従って、第一の記録液を第二の記録液より多くしたり、あるいは逆にしたり、全て同量にしたりできる。
【００６５】
【発明の効果】
以上説明したように、本発明によれば、各記録液の安定性を低下させず、また記録の信頼性の劣化もなしに、高記録濃度で、鮮やかで、且つ耐水性、耐光性が改善された高記録品位の記録が実現できる。
【００６６】
また、階調記録に適用した場合、記録速度の低下を招くことなく、そして各記録液の安定性を低下させず、また記録の信頼性の劣化もなしに、高記録濃度で、鮮やかで、且つ耐水性、耐光性が改善された高記録品位の階調カラー記録が実現できる。
【図面の簡単な説明】
【図１】本発明を適用したインクジェット記録装置の一実施例の要部を示す斜視図である。
【図２】図１の装置で使用する記録ヘッド部の各記録液に対応した記録ヘッドの配置例を示す図である。
【符号の説明】
４０…カラーインクジェットプリンタ
４２…キャリア
４４…紙送りローラ
４５…インクカートリッジ
５０…紙
６１、６２…第一に記録液の記録ヘッド
６５、６６、６７…第二の記録液の記録ヘッド
６８…ノズル[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a recording method using a recording liquid. More specifically, the first recording liquid using a water-soluble dye as a coloring material, and resin fine particles colored with a colorant and having an ionic group are colored. The present invention relates to a method and an apparatus for performing recording using a second recording liquid as a material.
[0002]
[Prior art]
The recording liquid used for recording on a recording medium such as paper (this "recording liquid" can be considered as synonymous with "ink") is roughly divided into a dissolved system and a dispersed system from the state of the color material in the liquid In addition, the type of solvent or dispersion medium used can be broadly classified into water-based aqueous and water-free solvent (oil). Each recording solution has advantages and disadvantages, and the recording solution considered to be optimal is selected and used in consideration of the use environment and main purpose.
[0003]
In offices and individuals where characters and images are recorded on a recording medium (paper, film, etc.), an aqueous recording liquid is generally used from the viewpoints of ease of handling, safety, and hygiene. The aqueous recording liquid is roughly classified into a dissolved aqueous recording liquid and a dispersed aqueous recording liquid based on the state of the color material as described above.
[0004]
Dissolving water-based recording liquids generally use water-soluble dyes as colorants, and have the advantage of being able to record vivid and good colors at relatively high concentrations, but have the disadvantage of poor water resistance and light resistance. There is. On the other hand, the aqueous dispersion recording liquid generally uses a pigment as a colorant and is dispersed in water by surface modification or addition of a dispersant such as a surfactant or a water-soluble resin in addition to making the pigment finer. However, it has the advantage of being excellent in water resistance and light resistance, but has the disadvantage of relatively low stability and recording with a dull color.
[0005]
On the other hand, the recording liquid is desired to be improved in recording density for the purpose of improving the recording quality. In order to improve the recording density, it is effective to increase the amount of the color material in the recording liquid. However, the increase in the amount of the color material tends to lower the stability of the recording liquid and has a limit. In particular, in an ink jet recording system that performs recording by discharging a recording liquid from a fine nozzle, the color material tends to solidify at the nozzle as the amount of the color material increases, resulting in recording defects such as missing dots. , Tend to reduce the reliability of recording. In recording using a recording liquid, priority is given to stable and high recording quality. For these reasons, except for black recording liquids that do not require high saturation, particularly color recording liquids that are used for color recording are dissolved aqueous recording liquids that have excellent liquid stability and can perform vivid recording at high concentrations. It has become mainstream to use.
[0006]
When using such a water-based aqueous recording liquid, in order to solve the disadvantages of light resistance and water resistance, an ink receiving layer is provided on the recording medium, and an ultraviolet absorber, a cationic water-soluble resin, etc. are provided on the ink receiving layer. A method for improving light resistance and water resistance by using an added dedicated recording medium is generally used.
[0007]
As alternative methods for improving light resistance and water resistance, a method of covering the recording surface of a recording medium with a film or a method of forming a film layer (for example, Japanese Patent Application Laid-Open Nos. 62-202782 and 8-252985, Japanese Laid-Open Patent Publication No. 8-258372) and a method of adding a resin to a recording liquid (for example, Japanese Patent Laid-Open No. 63-109083) have been proposed.
[0008]
Although the method of using a dedicated recording medium has a great effect, it has the disadvantages that the medium is expensive and has problems such as easy availability and commonality of the recording medium with other recording methods such as copying. Therefore, it is desired to use so-called plain paper in which paper fibers are exposed on a recording surface used for copying or the like rather than a dedicated recording medium.
[0009]
Further, in the method of covering the recording surface of the recording medium with a film or forming a film layer, the recording medium becomes thick and the handling property is deteriorated. In addition to the inconvenience of changing, it may be time consuming and may require a dedicated device.
[0010]
In the method of adding a resin to the recording liquid, even if the resin is insoluble in water, the resin itself is colorless and does not cover the dye that is a coloring material, so the dye on the recording medium dissolves in water. Thus, the water resistance is not improved, and even if an ultraviolet absorber is added for the same reason, the light resistance cannot be improved. Furthermore, special resin layer forming means may be required.
[0011]
In addition to these methods, as a method that is excellent in light resistance and water resistance and can be vividly recorded particularly in color recording, it can be dispersed in water by coloring with a colorant (dye or pigment) and containing an ionic group. A method using a recording liquid containing a polyester resin is proposed (for example, JP-A-4-296321, JP-A-7-196965, etc.). The characteristic of this recording liquid is that, as a coloring material, a water-insoluble polyester resin is used by coloring it with a colorant, and in particular, by using this colorant as a dye, a brighter and better color can be recorded, and the recording liquid is good. Water resistance is obtained. Furthermore, since the polyester resin has ultraviolet absorptivity, good light resistance can be obtained by adding an ultraviolet absorber to the resin as necessary. However, in order to improve the recording density, it is necessary to increase the colorant concentration for coloring the resin or increase the polyester resin concentration in the recording liquid. However, the solubility of the colorant in the resin is limited, and An increase in the resin concentration in the recording liquid not only greatly affects the physical properties of the recording liquid, such as an increase in the viscosity of the recording liquid, but also tends to decrease the stability of the recording liquid.
[0012]
As described above, in the prior art, a vivid and good color is realized by using a water-soluble dye as a coloring material or using a polyester resin that is colored with a dye and contains an ionic group and is water dispersible. Although it is not effective in improving water resistance and light resistance, or even if effective, it can improve recording quality such as increased recording density while ensuring the stability of recording liquid and recording reliability. Has not been realized.
[0013]
On the other hand, particularly in recent years, with the spread of personal computers and application software and the improvement in performance, there is an increasing demand for realizing high-quality gradation color recording suitable for recording so-called natural images such as photographs and video data. On the other hand, in a recording method using an aqueous recording liquid typified by an ink jet recording method, high-quality gradation recording is realized by using two types of light and dark inks having substantially the same hue. The above-mentioned problems of water resistance and light resistance remain, and no new measures have been proposed.
[0014]
[Problems to be solved by the invention]
Therefore, the present invention has a high recording density when recording on a recording medium using a recording liquid without reducing the stability of the recording liquid and the reliability of the recording, and also has water resistance and light resistance. An object of the present invention is to provide a recording method using a recording liquid capable of realizing excellent high-quality recording. It is also an object of the present invention to provide an apparatus for carrying out this method and a recording liquid cartridge used therein.
[0015]
[Means for Solving the Problems]
The recording method using the recording liquid of the present invention comprises: Same A recording method for recording a color recording liquid on a recording medium using the first and second recording liquids, the first recording liquid Water Use a solution containing soluble dye and water as the second recording liquid. Wear After using a resin fine particle colored with a colorant and containing an ionic group and water containing the fine particle dispersed therein, and recording on a recording medium with the first recording liquid, Same color as the first recording liquid The second recording liquid is characterized in that recording is performed so as to overlap at least a portion where recording has been performed with the first recording liquid on the recording medium.
[0016]
The recording apparatus of the present invention Same A recording apparatus for recording a color recording liquid on a recording medium using the first and second recording liquids. Water Use a solution containing soluble dye and water as the second recording liquid. Wear After using a resin fine particle colored with a colorant and containing an ionic group and water containing the fine particle dispersed therein, and recording on a recording medium with the first recording liquid, Same color as the first recording liquid The recording apparatus includes a unit that performs recording by superimposing at least a portion of the recording medium on which recording is performed with the second recording liquid.
[0017]
The recording liquid cartridge of the present invention is Same A cartridge for recording a color recording liquid on a recording medium using the first and second recording liquids. ,water A first recording liquid comprising a soluble dye and water; , Wearing Resin fine particles colored with a colorant and containing ionic groups and water for dispersing the fine particles The same as the first recording liquid It includes a combination of containers each containing a second recording liquid.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
In the present invention, the first recording liquid and the second recording liquid are used for at least one color. The first recording liquid contains at least a water-soluble dye as a coloring material and water, and the second recording liquid is colored with a colorant and contains an ionic group. Contains fine particles and water in which the fine particles are dispersed. Needless to say, both the first recording liquid and the second recording liquid contain, in addition to the coloring material and water, any optional components that may be added to normal recording liquids such as writing instruments and inkjet inks. it can.
[0019]
The water-soluble dye of the coloring material used in the first recording liquid can be arbitrarily selected from known dyes that dissolve in water according to the use environment and purpose of use.
[0020]
On the other hand, in the second recording liquid, resin fine particles which are colored with a colorant and contain an ionic group are used as a coloring material. For example, an aqueous dispersion of colored polyester resin particles having an ionic group can produce aqueous dispersions having an average particle size of about 0.3 μm or less and various particle sizes, and has a sharp particle size distribution, It is suitable for use as the resin fine particles of the second recording liquid of the present invention. As such a resin fine particle colorant, a dye or pigment that does not dissolve in water at room temperature can be used, so that the selection range of the color material is expanded and a color material having better characteristics can be used. As the ionic group, either an anionic group or a cationic group can be used.
[0021]
However, in general, pigments are excellent in water resistance and light resistance, but in the case of color, the vividness is low and the color reproduction range is narrow, and in the case of dyes, the vividness is high and the color reproduction range is wide. It is known that water resistance and light resistance are inferior to pigments including black. Therefore, in order to further enhance the effect of the present invention, it is more preferable that the resin fine particles are colored with a dye and applied to a color recording liquid. That is, by using a dye for coloring polyester resin or the like, it is possible to record with higher clarity and wider color reproducibility. In addition, by coloring a resin that does not dissolve in water with a dye that does not dissolve in water, the portion recorded with the second recording liquid using this colored resin as a coloring material naturally has higher water resistance. Since the resin absorbs ultraviolet rays which are a cause of dye fading, the resin of the second recording liquid covers the surface of the recording portion on the recording medium (that is, the portion on which the recording liquid is recorded on the recording medium). By doing so, the light resistance can be greatly improved. Addition of an ultraviolet absorber or the like as necessary also contributes to improvement of light resistance.
[0022]
Such resin fine particles can be prepared by, for example, synthesizing a polyester resin into which an ionic group is introduced, adding an appropriate dye to a solution obtained by dissolving the resin in a solvent, and then adding water to add the resin to the micro-dispersion. Thus, it can be easily manufactured. Examples of ionic groups include alkali metal sulfonates, ammonium sulfonates, alkali metal carboxylates, ammonium carboxylates, sulfuric acid groups, phosphoric acid groups, phosphonic acid groups, phosphinic acid groups, and ammonium acids of these acids. Anionic groups such as salts and metal salts and cationic groups such as primary to tertiary amine groups can be introduced. These resin fine particles and their production methods are well known from JP-A-4-296321 and JP-A-7-196965.
[0023]
In the present invention, recording liquids of a plurality of colors, usually three colors, can be used so as to enable color recording. In this case, the first and second types of recording liquids of at least one color are used. In other colors, only one type of recording liquid can be used. As described above, the color using only one type of recording liquid is colored with a colorant, particularly a dye, even if a recording liquid containing water-soluble dye and water (corresponding to the first recording liquid) is used. In addition, resin fine particles containing ionic groups and water containing the fine particles dispersed therein (corresponding to the second recording liquid) may be used, but in order to further enhance the effect of the present invention, It is preferable to use one corresponding to the second recording liquid. In addition, the first and second recording liquids used for the same color use different dyes and colorants having slightly different hues so as to show substantially the same hue when recorded on the recording medium. Is preferred.
[0024]
When recording is performed by the method of the present invention, recording is first performed on the recording medium using the first recording liquid, and then recording is performed using the second recording liquid. Recording is performed such that the second recording liquid is superimposed on a portion where recording has already been performed with at least the first recording liquid. In this way, a resin film is formed when the second recording liquid dries by at least partially covering the surface of the recording part of the first recording liquid with the resin fine particles of the second recording liquid. Since the water-soluble dye of the first recording liquid thereunder is coated, the water-based dye is prevented from dissolving in water, that is, the water resistance is improved.
[0025]
Further, the light resistance can be improved by using, for example, a polyester resin having a property of absorbing ultraviolet rays as the resin of the second recording liquid. In addition, since the second recording liquid is superimposed on the recording portion of the first recording liquid, the first recording liquid and the second recording are also used for the recording of the portion that requires a high recording density. The recording density of the portion can be improved without increasing the colorant density of the liquid, and the stability of the recording liquid and the recording reliability can be ensured.
[0026]
For color recording using both the first and second recording liquids, it is necessary to superimpose the second recording part on the recording part of the first recording liquid, and both cannot be recorded simultaneously. Therefore, it is desirable that the first recording liquid is fixed after recording with the first recording liquid and before recording with the second recording liquid. Therefore, in the present invention, at least the first recording liquid is added with a penetrant or the like to accelerate the penetration of the recording liquid into the recording medium, thereby speeding up the fixing. It is possible to prevent a decrease in recording speed due to the fact that simultaneous recording with liquid is not possible.
[0027]
In the present invention, taking advantage of the characteristics of the dye-based aqueous recording liquid, for the same color, the first recording liquid is used as a dark recording liquid, and the second recording liquid is used as a light recording liquid. By recording the second recording liquid on the recording part of the first recording liquid, the density of the high density recording part can be further improved, and the second recording liquid is recorded on the low density recording part. In the intermediate density recording portion, the second recording liquid is recorded on the first recording liquid, and the second recording liquid is recorded in the portion where no recording is performed with the first recording liquid. By recording a pattern that combines recording with a liquid, and thus at least partially covering all the recorded portions with resin fine particles after the recording liquid is dried, it is excellent in light resistance, water resistance, high quality, Gradation recording with excellent stability and recording reliability
[0028]
Furthermore, in color recording using at least three recording liquids of yellow, magenta, and cyan, the second recording liquid is used for yellow, which is generally designed to have a lower recording density than the other two-color high-density recording liquids. By using the first and second recording liquids for magenta and cyan, which require high recording density and low recording density, respectively, excellent light resistance, water resistance, high quality, and stability of the recording liquid And full-color gradation recording suitable for recording natural images with excellent recording reliability. At this time, by adding a penetrant or the like, the fixing time of each recording liquid is set to a short time that does not cause so-called bleeding, which is a color mixing phenomenon caused by the recording liquid flowing out at the color boundary portion on the recording medium. Thus, color recording with higher recording quality becomes possible.
[0029]
【Example】
The invention will now be further described by way of examples.
[0030]
[Example 1]
In this example, a case where an inkjet recording method is used and polyester is used as the resin of the second recording liquid will be described.
[0031]
A method for producing an aqueous dispersion of polyester resin fine particles colored with a dye is described in detail in JP-A-4-296321. In particular, JP-A-7-196965 discloses the production of an ink jet recording liquid (ink). An example of the method is described. According to the procedure described in these, first, the transesterification reaction was performed by heating for 120 minutes at 180-230 degreeC using the following substance, and copolyester resin was manufactured.
[0032]

[0033]
100 parts by weight of this polyester resin and the following dye as a colorant
[0034]
C. I. Solvent Blue 64 6 parts by weight
[0035]
And the following solvent
[0036]
175 parts by weight of methyl ethyl ketone
175 parts by weight of tetrahydrofuran
[0037]
After the resin and dye are dissolved, 600 parts by weight of water is added to make the resin fine particles. The resin is filtered and distilled through a membrane filter having a pore size of 0.8 μm to obtain a solid content concentration of about 30. An aqueous dispersion having a weight percent average particle size of about 0.18 μm was obtained.
[0038]
50% by weight of the cyan aqueous dispersion thus obtained, 12% by weight of glycerin as a wetting agent, 0.8% by weight of a nonionic surfactant (surfinol manufactured by Air Products) as a penetrating agent, and water 37 2 wt% was mixed to prepare a second recording liquid having a viscosity of about 4 cP and a surface tension of about 32 dyn / cm. The solid content concentration contained in this recording liquid was about 15% by weight.
[0039]
On the other hand, the water-soluble dye C.I. I. Acid Blue 9 3% by weight, wetting agent diethylene glycol 15% by weight, penetration regulator ethyl alcohol 2% by weight, penetrant nonionic surfactant (Surfinol manufactured by Air Products) 1.0% by weight, water 79% by weight The first recording liquid having a viscosity of about 2.5 cP and a surface tension of about 30 dyn / cm was prepared by mixing, dissolving, and filtering through a membrane filter having a pore size of 0.8 μm.
[0040]
These recording liquids were solid-recorded at a resolution of 360 dpi (recording performed at a single density on the entire surface of the recording medium) using Xerox plain paper XEROX 4024DP manufactured by Xerox Corporation as the recording medium. At this time, the fixing time of each recording liquid is defined as the time when the liquid recording liquid does not remain on the recording medium, and the time until the recording liquid is no longer observed on the paper after the recording surface is lightly pressed with the paper is measured. As a result, the fixing time of each recording liquid was less than about 1 second.
[0041]
Next, about 1 second after recording the first recording liquid under the same conditions as described above, the second recording liquid was recorded over the recording portion. Also, under the same conditions as described above, about 1 second after the first recording liquid was first recorded, the first recording liquid was recorded over the recording portion.
[0042]
After the solid recording sample thus obtained was left for one day, the recording density (status A density), the color difference (water resistance ΔE) of the recorded part before and after being immersed in tap water for about 1 minute, ultraviolet light with an ultraviolet lamp The color difference (light-resistant ΔE) of the recorded part before and after being irradiated for 1 hour was measured and compared. The results are shown in Table 1.
[0043]
[Table 1]

[0044]
From these results, it was confirmed that the recording density was improved by overlapping the first recording liquid and the second recording liquid. Further, it was confirmed that the light resistance and the water resistance were improved by recording the second recording liquid on the first recording liquid. Note that this effect is not simply due to the performance of the second recording liquid. When the second recording liquid is superimposed on the first recording liquid, the first recording liquid is overlaid on the first recording liquid. It is clear from the fact that the light resistance and water resistance are superior to the case where the recording liquids are stacked.
[0045]
This effect is considered to be because the resin particles of the second recording liquid adhere to the recording surface of the first recording liquid and at least partially cover the recording surface. Therefore, it is considered that the larger the amount of resin fine particles of the second recording liquid that is deposited on the recording surface of the first recording liquid, the greater the effect. When the resin fine particles are large, the fine particles can be combined to form a film, and therefore, water resistance and light resistance can be further improved, and gloss can be imparted. In order to increase the resin fine particles, there are a method of increasing the amount of resin in the recording liquid, a method of increasing the amount of recording liquid to be recorded, a method of recording the second recording liquid in a plurality of times, and the like. Further, in order to facilitate film formation, the glass transition point of the resin may be lowered. However, since the stability of the resin fine particles tends to decrease if the glass transition point is lowered, the temperature margin of the recording liquid, etc. It is necessary to set in consideration of reliability. In the resin of this example, the glass transition point was about 70 ° C.
[0046]
In this example, the second recording liquid was overlaid and recorded about 1 second after the first recording liquid was recorded. However, the recording portion with the first recording liquid was sufficiently dried after a longer time. If the second recording liquid is superposed after that, the resin tends to remain on the recording surface, and a greater effect can be expected, but the recording speed becomes slower.
[0047]
In this embodiment, in order to increase the recording speed, a penetrant is also added to the second recording liquid. However, the second recording liquid is recorded within about 1 second after recording the first recording liquid. When the recording medium is overlaid, the recording medium is wet due to the influence of the first recording liquid, and the recording liquid is easily absorbed. Therefore, no penetrant is added to the second recording liquid. Rather, it is preferable not to add a penetrating agent in order to further increase the residual resin on the recording surface.
[0048]
[Example 2]
Next, an embodiment in the case of color gradation recording will be described.
[0049]
It is known that good gradation recording can be obtained by using recording liquids having substantially the same hue and different densities. It is known that yellow may have a lower temperature than the recording liquids of other hues because of its color, and it is not necessary to use two types of recording liquids having different concentrations. Therefore, here, a case where color gradation recording is performed using the first and second recording liquids of magenta and the second recording liquid of yellow in addition to the first and second recording liquids of cyan described above will be described. To do.
[0050]
As a dye,
[0051]
C. I. Solvent Yellow 162 20 parts by weight
C. I. Disperse Red 92 8 parts by weight
[0052]
Were used to prepare second recording liquids of yellow and magenta in the same manner as described above. The viscosity of each recording liquid was about 3 cP for yellow, about 4 cP for magenta, and the surface tension was about 32 dyn / cm.
[0053]
In addition,
[0054]
C. I. Acid Red 249 4% by weight
[0055]
Was used to prepare a first recording liquid of magenta by the same method as described above. This recording liquid had a viscosity of about 2.5 cP and a surface tension of about 30 dyn / cm.
[0056]
In the case of color recording, the fixing time of the recording liquid is slow, and when liquid recording liquids of different colors come into contact with the surface of the recording medium, the recording liquid diffuses, flows out, and mixes to develop so-called bleed and reduce recording quality. In this embodiment, in order to reduce or prevent this bleed, a penetrant is added to each recording liquid, and the fixing time is shortened by quickly absorbing the recording liquid into the recording medium, thereby reducing the bleed. . However, the portion where the second recording liquid, particularly the low density magenta or cyan, is recorded is a portion having a low recording density called a highlight portion, so that a large amount of recording liquid is not recorded. As a result, the recording liquids having different hues are less likely to come into contact with each other and cause bleeding. Therefore, it is not necessary to add a penetrant to magenta and cyan in the second recording liquid, and even if added, the amount can be reduced as compared with other recording liquids.
[0057]
As the recording apparatus, the first and second recording liquids prepared as described above can be used, and various apparatuses that can perform recording with the second recording liquid after recording with the first recording liquid can be used. In the printer, the configuration shown in FIG. 1 can be given as an example. According to such a configuration, the present invention can be realized without lowering the recording speed, and gradation recording with high quality and high water resistance and light resistance can be realized.
[0058]
A serial type color ink jet printer 40 shown in FIG. 1 has a recording head (not shown) having a nozzle for discharging a recording liquid and an ink cartridge 45 holding the recording liquid connected and integrated to form a main arrow X. It is mounted on a carrier 42 that moves in the scanning direction. The recording medium paper 50 is conveyed by the paper feed roller 44 in the sub-scanning direction indicated by the arrow Y.
[0059]
The recording head portion is located at a position where the nozzle surface with the nozzle for discharging the recording liquid faces the recording medium. The recording head is reciprocated in the main scanning direction indicated by an arrow X using the stay shaft 43 as a guide, and the recording liquid is based on the image data. By discharging, dots are formed on the recording medium. On the other hand, the paper 50, which is a recording medium, moves a predetermined distance in the sub-scanning direction Y corresponding to the recording width recorded by one scanning of the recording head unit. By repeating this basic operation, an image composed of dots is recorded.
[0060]
FIG. 2 shows an example of the arrangement of the recording head corresponding to each recording liquid. That is, in parallel to the main scanning direction X, two recording heads 61 and 62 corresponding to the first recording liquid magenta and cyan are arranged to provide the recording head row A, and the second recording liquid yellow and magenta The recording head row B is provided by arranging three recording heads 65, 66, and 67 corresponding to cyan. Each recording head is provided with a predetermined number of nozzles 68 used for discharging each recording liquid. In the case of a recording head unit employing the head arrangement shown in this figure, the sub-scan is performed so that the recording by the recording head array A is performed before the recording by the recording head array B at the same position on the recording medium. In parallel to the direction Y, the recording head array A and the recording head array B are arranged so that the recording head array A is at the head, thereby forming a recording head unit. By configuring the head portion in this way, when the first recording liquid and the second recording liquid are overlapped and recorded on the recording medium, the first recording liquid is always recorded first. Furthermore, although depending on the resolution of recording, the maximum ejection frequency of the recording liquid ejected from the nozzle, the recording width, etc., the second ink can be overlaid after the time of one sub-scan has elapsed, and the recording apparatus Since the present invention can be realized within a recording speed of 2 and after recording with the first recording liquid, it takes a long time to record the second recording liquid. Large records can be realized.
[0061]
As another example of the recording head unit, a plurality of recording heads corresponding to the first recording liquid are arranged in parallel to the main scanning direction X, and a plurality of recording heads corresponding to the second recording liquid are arranged in the first recording liquid. An arrangement in which the heads corresponding to the recording liquids are arranged in parallel to the main scanning direction X following the row of recording heads corresponding to the recording liquids and the heads corresponding to the recording liquids are arranged in a line can be given. In this case, when recording is performed by reciprocally scanning the recording head portion, the recording speed is not decreased by recording the first recording liquid in the forward path and the second recording liquid in the subsequent backward path. The present invention can be implemented.
[0062]
As a result of gradation recording at a resolution of 720 dpi and a maximum ejection frequency of recording liquid of 7 kHz using a cartridge employing the recording head arrangement described with reference to FIG. It was possible to obtain a high-quality gradation image with improved light resistance and water resistance.
[0063]
In this embodiment, recording is performed using three colors of yellow, magenta, and cyan. However, it is also possible to perform recording with four color recording liquids by adding a black recording liquid to these three color recording liquids. . In this case, the black recording liquid is a known dye system, a dispersion system in which a pigment such as carbon black having excellent light resistance and water resistance is dispersed, the second recording liquid in the present invention, or the first recording liquid according to the present invention. A combination of the first and second recording liquids can be used. However, in order to further enhance the effect of the present invention, it is preferable to use a liquid having excellent water resistance and light resistance such as a pigment dispersion type recording liquid.
[0064]
Also, various methods for producing the recording liquid, constituent materials, etc. can be used, and the present invention is not limited to the above examples. Further, various recording devices and recording liquid containers (cartridges) can be used, and it goes without saying that the present invention is not limited to the above examples. In addition, the amount of each recording liquid (capacity of the cartridge) can be made to be larger than the second recording liquid or vice versa mainly according to the image data to be recorded, or the same amount.
[0065]
【The invention's effect】
As described above, according to the present invention, the stability of each recording liquid is not lowered, and the reliability of recording is not deteriorated, and the recording density is high, and the water resistance and light resistance are improved. High recording quality can be achieved.
[0066]
In addition, when applied to gradation recording, without causing a decrease in recording speed, without reducing the stability of each recording liquid, and without degrading the reliability of recording, high recording density, vivid, In addition, high-quality gradation color recording with improved water resistance and light resistance can be realized.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a main part of an embodiment of an ink jet recording apparatus to which the present invention is applied.
2 is a diagram showing an example of the arrangement of recording heads corresponding to the recording liquids of the recording head unit used in the apparatus of FIG.
[Explanation of symbols]
40 ... Color inkjet printer
42 ... Career
44. Paper feed roller
45. Ink cartridge
50 ... paper
61, 62 ... First, a recording liquid recording head
65, 66, 67 ... second recording liquid recording head
68 ... Nozzle

Claims

A recording method for recording on a recording medium using the first and second recording liquids for the same color recording liquid, wherein the first recording liquid contains a water-soluble dye and water, A recording liquid containing resin fine particles colored with a colorant and containing ionic groups and water in which the fine particles are dispersed is used, and recording is performed on the recording medium with the first recording liquid. And recording with a second recording liquid of the same color as the first recording liquid overlaid on at least a portion of the recording medium on which recording has been performed.

The method according to claim 1, wherein the first recording liquid and the second recording liquid for the same color are recording liquids using dyes and colorants having the same color and different types.

3. The method according to claim 1, wherein color recording is performed using at least two sets of first and second recording liquids having different colors.

The method according to any one of claims 1 to 3, wherein the first recording liquid contains a penetration enhancer that promotes penetration of the recording liquid into the recording medium.

The first recording liquid and the second recording liquid of the same color are used as the second recording liquid whose recording density is lower than the recording density of the first recording liquid . The method according to any one of the above.

A recording apparatus for recording on a recording medium using the first and second recording liquids for the same color recording liquid, wherein the first recording liquid contains a water-soluble dye and water, A recording liquid containing resin fine particles colored with a colorant and containing ionic groups and water in which the fine particles are dispersed is used, and recording is performed on the recording medium with the first recording liquid. And a means for recording the second recording liquid having the same color as that of the first recording liquid on the recording medium on the recording medium. apparatus.

The apparatus scans a plurality of recording heads corresponding to a plurality of recording liquids having nozzles that face the recording medium and discharge the recording liquid onto the recording medium in a main scanning direction, and a sub-scanning direction perpendicular to the main scanning direction And a serial type ink jet printer that performs recording by sub-scanning the recording medium, wherein a plurality of recording heads corresponding to the first recording liquids of different colors are arranged in parallel in the main scanning direction. A second recording liquid recording head array in which a recording liquid recording head array and a plurality of recording heads corresponding to each of the second recording liquids having different colors are arranged in parallel in the main scanning direction is arranged in the main scanning direction. A position where the recording head row of the first recording liquid is at the head in the sub-scanning direction so that the first recording liquid is recorded before the second recording liquid. It is characterized by being placed in The recording apparatus according to claim 6, wherein.

The apparatus scans a plurality of recording heads corresponding to a plurality of recording liquids having nozzles that face the recording medium and discharge the recording liquid onto the recording medium in a main scanning direction, and a sub-scanning direction perpendicular to the main scanning direction A serial type ink jet printer that performs scanning by sub-scanning the recording medium, and a plurality of recording heads corresponding to the first recording liquids having different colors and the second recording liquids having different colors. A recording head array in which a plurality of corresponding recording heads are arranged in a line parallel to the main scanning direction is provided, the first recording liquid is recorded during the forward scanning in the main scanning direction of the recording head array, and the subsequent backward scanning 7. The recording apparatus according to claim 6 , wherein the second recording liquid is sometimes recorded.

A cartridge for recording on a recording medium using the first and second recording liquids of the same color recording liquid, which is colored with a first recording liquid containing a water-soluble dye and water, and a colorant. And a combination of containers each containing a second recording liquid identical to the first recording liquid, the resin containing fine particles containing an ionic group and water in which the fine particles are dispersed. Recording liquid cartridge to be used.