JP3882261B2 - Recording liquid, ink jet recording method, and dye for recording liquid - Google Patents

Description

【０００９】
（一般式〔Ｉ〕において、Ａは置換されていてもよいフェニレン基又はナフチレン基を表わし、Ｖ及びＷは、各々独立に水素原子、置換もしくは非置換の炭素数１〜４のアルキル基又は置換もしくは非置換の炭素数１〜４のアルコキシ基を表わし、Ｒ ¹ 、Ｒ² 及びＲ³ は、各々独立に水素原子、置換もしくは非置換の炭素数１〜４のアルキル基、置換もしくは非置換の炭素数１〜４のアルコキシ基、水酸基、ハロゲン原子、カルボキシル基又は、炭素数１〜４のアルキル基もしくは炭素数２〜１２のアシル基で置換されたアミノ基を表わし、Ｒ⁴ 及びＲ⁵ は、各々独立に、水素原子、置換もしくは非置換の炭素数１〜４のアルキル基を表わし、ｌは１又は２を表わし、ｍは０又は１を表わす。）
【００１０】
【化４】

【００１１】
（一般式〔II〕において、Ｂは置換されていてもよいフェニレン基又はナフチレン基を表わし、Ｘ及びＹは、各々独立に水素原子、置換もしくは非置換の炭素数１〜４のアルキル基又は置換もしくは非置換の炭素数１〜４のアルコキシ基を表わし、Ｒ ⁶ 及びＲ⁷ は各々独立に水素原子、水酸基、ニトロ基又は、置換もしくは非置換のアミノ基を表わし、Ｒ⁸ 及びＲ⁹ は各々独立に水素原子、置換もしくは非置換の炭素数１〜４のアルキル基を表わし、ｎは１、２、又は３を表わし、ｐは０又は１を表わす。）
【００１２】
【発明の実施の形態】
以下に、本発明を詳細に説明する。
本発明において用いられる色素は、前記請求項１において、一般式〔Ｉ〕又は〔II〕で表わされる。詳しくは、一般式〔Ｉ〕について、Ａにおけるフェニレン基の置換基としては、炭素数１〜４のアルコキシ基、水酸基、炭素数１〜４のヒドロキシアルコキシ基等の置換基を有していてもよい炭素数１〜４のアルキル基；炭素数１〜４のアルコキシ基；炭素数２〜６のアルキルカルボニルアミノ基、炭素数７〜１２のアリールカルボニルアミノ基等のアシルアミノ基；ＳＯ₃ Ｈ基；カルボキシル基等が挙げられ、Ａにおけるナフチレン基の置換基としては、ＳＯ₃ Ｈ基、カルボキシル基、炭素数１〜４のアルコキシ基等が挙げられる。Ａの置換基は２個以上であってもよい。
【００１３】
Ｖ及びＷは、炭素数の和が２以上であるのが好ましく、Ｖ及びＷで表わされるアルキル基の置換基としては、例えばフェニル基等が挙げられ、アルコキシ基の置換基としては、アルコキシ基、水酸基、フェニル基、ベンジルオキシ基、カルボキシル基等が挙げられる。
Ｒ¹ 、Ｒ² 及びＲ³ について、アルキル基の置換基としては、水酸基及び炭素数１〜４のアルコキシ基等が挙げられ、アルコキシ基の置換基としては炭素数１〜４のアルコキシ基等が挙げられる。アミノ基の置換基としては炭素数１〜４のアルキル基及び炭素数２〜１２のアシル基等が挙げられる。
【００１４】
Ｒ⁴ 及びＲ⁵ で表わされるアルキル基の置換基としては、炭素数１〜４のアルコキシ基、カルボキシル基、水酸基等が挙げられる。
一般式〔II〕について、Ｂにおけるフェニレン基の置換基としては炭素数１〜４のアルコキシ基、水酸基、炭素数１〜４のヒドロキシアルコキシ基等の置換基を有していてもよい炭素数１〜４のアルキル基；炭素数１〜４のアルコキシ基、水酸基、炭素数１〜４のヒドロキシアルコキシ基等の置換基を有していてもよい炭素数１〜４のアルコキシ基；炭素数１〜６のアルキルカルボニルアミノ基、炭素数７〜１２のアリールカルボニルアミノ基等のアシルアミノ基；ＳＯ₃ Ｈ基；カルボキシル基が挙げられ、Ｂにおけるナフチレン基の置換基としては、ＳＯ₃ Ｈ基、カルボキシル基、炭素数１〜４のアルコキシ基が挙げられる。Ｂの置換基は２個以上であってもよい。
【００１５】
Ｘ及びＹは、炭素数の和が３以上であるのが好ましく、Ｘ及びＹで表わされるアルキル基の置換基としては、例えばフェニル基等が挙げられ、アルコキシ基の置換基としては、アルコキシ基、水酸基、フェニル基、ベンジルオキシ基、カルボキシル基等が挙げられる。
Ｒ⁶ 及びＲ⁷ において、アミノ基の置換基としては、炭素数１〜４のアルキル基、炭素数２〜１２のアシル基等が挙げられる。
【００１６】
Ｒ⁸ 及びＲ⁹ において、アルキル基の置換基としては、炭素数１〜４のアルコキシ基、カルボキシル基、炭素数２〜４のヒドロキシアルキル基等が挙げられる。
本発明において一般式〔Ｉ〕又は〔II〕で示される色素は、一般式〔Ｉ〕又は〔II〕に示されるような遊離酸型でもよいが、色素製造後、塩型で得られた場合はそのまま、あるいは所望の塩型に造塩されたものであっても良く、また一部が酸型、一部が塩型となったものでもよい。
【００１７】
このような塩型の場合に塩を形成するものの例としては、カリウム、ナトリウム、リチウム等のアルカリ金属、炭素数１〜８程度のアルキル基もしくはヒドロキシアルキル基等で置換されていてもよいアンモニウム基及び有機アミンがあり、これらが混在していてもよい。このうち、有機アミンの例としては、有機基で置換された１〜３級置換アミンであり、炭素数１〜４程度の、低級アルキルアミン、ヒドロキシ置換低級アルキルアミン、カルボキシ置換低級アルキルアミン、及び炭素数２〜４のアルキレンイミン単位を２〜１０個有するポリアミン等が挙げられる。
これ等の色素の具体例としては、例えば以下のＩ−（１）〜Ｉ−（１３）及びII−（１）〜II−（８）に示す構造のアゾ染料が挙げられる。
【００１８】
【化５】

【００１９】
【化６】

【００２０】
【化７】

【００２１】
【化８】

【００２２】
【化９】

【００２３】
一般式〔Ｉ〕及び〔II〕で示されるアゾ染料は、それ自体周知の方法〔例えば、細田豊著「新染料化学」（昭和４８年１２月２１日 技報堂発行）第３９６〜４０９頁参照〕に従って、ジアゾ化、カップリング工程を経て製造する事ができる。
一般式〔Ｉ〕又は〔II〕で示されるアゾ染料は、グラム吸光係数（水中の色素濃度１ｇ／ｌのときの最大吸収波長における吸光度）が５０〜１２０と高く、発色性も良好であるため、記録液の組成が前記した上乗せ型組成であっても、浸透型組成であっても、十分な印字濃度の画像を得ることができる。
【００２４】
記録液中における前記一般式〔Ｉ〕又は〔II〕の染料の含有量としては、記録液全量に対して０．５〜１２重量％、特に２〜８重量％程度が好ましい。
本発明においては、前記一般式〔Ｉ〕又は〔II〕で示される色素を単独あるいは複数使用する。複数の場合は、それぞれの一般式のものを複数種使用しても良いが、双方の一般式の色素をそれぞれ一種以上づつ使用するのでもよい。
【００２５】
また、他の周知の黒色色素を併用したり、色調調整のために、他の色調（例えばマゼンタ、シアン、イエロー）の色素を併用してもよい。
本発明に用いられる水性媒体としては、水及び水溶性有機溶剤として、例えばエチレングリコール、プロピレングリコール、ブチレングリコール、ジエチレングリコール、トリエチレングリコール、ポリエチレングリコール（重量平均分子量（Ｍｗ）＝１９０〜４００）、グリセリン、Ｎ−メチルピロリドン、Ｎ−エチルピロリドン、１，３−ジメチルイミダゾリジノン、チオジエタノール、ジメチルスルホキシド、エチレングリコールモノアリルエーテル、エチレングリコールモノメチルエーテル、ジエチレングリコールモノメチルエーテル、ジエチレングリコールモノブチルエーテル、トリエチレングリコールモノブチルエーテル、２−ピロリドン、スルホラン、エチルアルコール、イソプロピルアルコール、トリエタノールアミン等を含有しているのが好ましい。これ等の水溶性有機溶剤は、通常記録液の全量に対して１〜５０重量％の範囲で使用される。一方、水は記録液の全量に対して４５〜９５重量％の範囲で使用される。
【００２６】
本発明の記録液に、その全量に対して０．１〜１０重量％、好ましくは０．５〜５重量％の尿素、チオ尿素、ビウレット、セミカルバジドから選ばれる化合物を添加したり、又０．００１〜５．０重量％の界面活性剤を添加することによって、印字後の速乾性及び印字品位をより一層改良することができる。
【００２７】
本発明の記録液はそれ自体黒色であって黒色の画像を形成するのは勿論、マルチカラーないしフルカラーの画像についても、イエロー、マゼンタ及びシアンの各色の記録液を併用することにより形成することができる。具体的には、イエローについては、例えばＣ．Ｉ． Ｄｉｒｅｃｔ Ｙｅｌｌｏｗ ８６、１４２、もしくは１３２、又はＣ．Ｉ． Ａｃｉｄ Ｙｅｌｌｏｗ ２３等の少なくとも一種、マジェンタについては、例えばＣ．Ｉ． Ａｃｉｄ Ｒｅｄ ３５、３７、５２、２５７、もしくは２８９、または、Ｃ．Ｉ． Ｄｉｒｅｃｔ Ｒｅｄ８０等の少なくとも一種、シアンについては、例えばＣ．Ｉ． ＤｉｒｅｃｔＢｌｕｅ ８６、もしくは１９９、又は、Ｃ．Ｉ． Ａｃｉｄ Ｂｌｕｅ ９等の少なくとも一種の色素を含有する記録液を本発明の記録液と併用することにより形成することができる。該黒色以外の記録液は、上記の色素を使用する以外は、本発明の記録液と同様の組成であるのが好ましい。すなわち、上記の色素の他に水性媒体及び必要に応じて各種添加物を含むものである。
【００２８】
本発明の記録液は、インクジェット記録用、筆記用具用等に使用するのに適するが、特に、インクジェット記録用に適している。
該インクジェット記録用の装置の吐出手段としては、電気エネルギー、熱エネルギー等を用いたものが使用できる。
【００２９】
【実施例】
以下本発明を実施例について更に詳細に説明するが、本発明のその要旨を超えない限りこれ等の実施例に限定されるものではない。
実施例１
ジエチレングリコール１０重量部、イソプロピルアルコール３重量部、前記Ｎｏ．Ｉ−（１）の色素３重量部に水を加え、苛性ソーダ水でｐＨを９に調整して全量を１００重量部とした。この組成物を充分に混合して溶解し、孔径１μｍのテフロンフィルターで加圧濾過した後、真空ポンプ及び超音波洗浄機で脱気処理して記録液を調製した。
【００３０】
得られた記録液を使用し、インクジェットプリンター（商品名 ＢＪ−１０Ｖ、キャノン社製品）を用いて電子写真用紙（ゼロックス社製品）にインクジェット記録を行い、高濃度（１．３５）の黒色の印字物を得た。また、下記（ａ）、（ｂ）、（ｃ）、（ｄ）及び（ｅ）の方法による諸評価を行なった。結果を第１表に示す。
【００３１】
（ａ）記録画像の耐光性：
キセノンフェードメーター（スガ試験機社製品）を用い、記録紙に１００時間照射した。照射後の変退色は小さかった。
（ｂ）記録画像の耐水性：
耐水性試験
（１）試験方法
水道水中に記録画像を５分間浸漬したのち、
▲１▼ 目視にて画像の滲みを調べた。
▲２▼ 浸漬前後のベタ印字部分のＯＤ値（印字濃度）をマクベス濃度計（ＴＲ９２７）にて測定した。
（２）試験結果
上記▲１▼の結果、画像の滲みはわずかであった。
上記▲２▼の浸漬前後のベタ印字部分の濃度変化を下記式によるＯＤ残存率の値で示すと、８３．１％であった。
【００３２】
【数１】
ＯＤ残存率（％）＝（浸漬後ＯＤ値／浸漬前ＯＤ値）×１００
【００３３】
（ｃ）記録液の保存安定性：
記録液をテフロン容器中に密閉し、５℃で１か月間及び７０℃で６日間保存した後の変化を調べたところ、色素の分解及び不溶物の析出は認められなかった。
（ｄ）溶解性
前記した記録液の調製において、孔径１μｍのテフロンフィルターでの加圧濾過に先立って室温にて１日放置し、加圧濾過後に目視観察を行なった。その結果、フィルター上に濾過残渣は認められなかった。
【００３４】
（ｅ）吐出の安定性：
気温３０℃、相対湿度２０％に調整された室内でも３時間連続して安定な吐出が可能であった。
以上の（ａ）、（ｂ）、（ｃ）、（ｄ）及び（ｅ）の評価において、目視判定は○：良好、△：やや劣る、×：不良の三段階で評価した。
【００３５】
実施例２〜４
実施例１において用いた前記Ｎｏ．Ｉ−１の色素の代わりに、前記Ｎｏ．Ｉ−２、Ｎｏ．II−１、及びＮｏ．II−２の色素をそれぞれ使用した以外は、実施例１の方法により、記録液を調製し、これを用いて印字を行い、黒色の記録物を得た。更にこの記録物に対して実施例１の（ａ）〜（ｅ）による諸評価を行った。この結果、実施例１と同様に何れも良好な結果を得た。ＯＤ残存率は各々８０．５％、７９．８％、８４．２％であった。結果を以下の第１表に示す。
【００３６】
比較例１
実施例におけるＮｏ．Ｉ−１の色素の代わりにＣ．Ｉ．フードブラック２を用い、実施例１と同様にして組成物を調製、次いで処理して記録液を得た。この記録液を用い、実施例１と同様に印字し、黒色の記録物を得た。得られた記録物に対して実施例１の（ａ）〜（ｅ）による諸評価を行った。結果を以下の第１表に示す。
【００３７】
比較例２
実施例１におけるＮｏ．Ｉ−１の色素の代わりに特開平７−２０７２０４号に記載されている色素Ｎｏ．（１１）（下記構造式＊１）の色素を用い、実施例１と同様にして組成物を調製、次いで処理して記録液を得た。この記録液を用い、実施例１と同様に印字し、黒色の記録物を得た。得られた記録物に対して実施例１の（ａ）〜（ｅ）による諸評価を行った。結果を以下の第１表に示す。
【００３８】
比較例３
実施例１におけるＮｏ．Ｉ−１の色素の代わりに特開昭６１−２８５２７６号に記載されている色素Ｎｏ．（１）（下記構造式＊２）の色素を用い、実施例１と同様にして組成物を調製、次いで処理して記録液を得た。この記録液を用い、実施例１と同様に印字し、黒色の記録物を得た。得られた記録物に対して実施例１の（ａ）〜（ｅ）による諸評価を行った。結果を以下の第１表に示す。
【００３９】
【化１０】

【００４０】
【表１】

【００４１】
実施例５
グリセリン１０重量部、ジエチレングリコールモノブチルエーテル５重量部、２−ピロリドン５重量部、前記Ｎｏ．（II）−６の色素４．５重量部に水を加え、１％水酸化リチウム水溶液でｐＨを９に調整して全量を１００重量部とした。実施例１の方法により記録液を調製し、印字を行い、黒色の記録物を得た。この記録物に対して実施例１の（ａ）〜（ｄ）による諸評価を行なった。その結果、実施例１と同様に何れも良好な結果を得た。
【００４２】
実施例６〜２１
実施例１において用いた前記Ｎｏ．Ｉ−１の色素の代わりに、前記Ｎｏ．Ｉ−（３）、Ｎｏ．Ｉ−（４）、Ｎｏ．Ｉ−（５）〜Ｉ−（１３）、Ｎｏ．II−（３）〜（５）及びＮｏ．II−（７）〜（８）の色素のそれぞれを使用し、実施例１の方法により記録液を調製し、印字を行い、黒色の記録物を得た。この記録物に対して実施例１の（ａ）〜（ｅ）による諸評価を行なった。その結果、実施例１と同様に何れも良好な結果を得た。
【００４３】
【発明の効果】
本発明の記録液は、インクジェット記録用、筆記用具用等として用いられ、普通紙に記録した場合、黒色系の記録物を得ることができ、その印字濃度及び耐光性、耐水性が優れている他、記録液としての保存安定性及び吐出安定性も良好である。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a recording liquid. Specifically, the present invention relates to a black recording liquid suitable for ink jet recording.
[0002]
[Prior art]
A so-called ink jet recording method has been put to practical use in which recording is performed by ejecting droplets of a recording liquid containing a direct dye or a water-soluble dye such as an acid dye from a minute ejection orifice. This recording liquid is widely used for general office work such as PPC (plain paper copier) paper such as electrophotographic paper, fan hold paper (continuous paper such as computer), etc. It requires fast fixing to recording paper and good print quality, that is, the print must have no blur and have a clear outline, and has excellent stability when stored as a recording liquid. Therefore, the solvents that can be used for the recording liquid are remarkably limited.
[0003]
On the other hand, the dye for the recording liquid has sufficient solubility in the limited solvent as described above, and is stable when stored as a recording liquid for a long time, and the density of the printed image. However, it is difficult to satisfy many of these requirements at the same time.
For this reason, various methods (for example, JP-A-55-140667, JP-A-55-152747, JP-A-57-207660, JP-A-59-226072, JP-A-61-27776, JP-A-5-2776 61-57666, JP 62-190269, JP 62-190271, JP 62-190272, JP 62-197476, JP 62-250082, JP 62- No. 246975, JP-A 62-256974, JP-A 62-288659, JP-A 63-8463, JP-A 63-22867, JP-A 63-117079, JP-A 63-30567 JP-A-63-33484, JP-A-63-63964, JP-A-63-105079, JP-A-64-31877, JP-A-1-93389, JP-A-1-21046. No. 1, JP-A No. 1-240584, JP-A No. 2-16171, JP-A No. 2-140270, JP-A No. 3-2000882, and JP-A No. 5-262998) have been proposed. The demand is not fully satisfied.
[0004]
JP-A-61-285276 and JP-A-7-207204 describe dyes having a structure similar to that of the present invention.
These have been used as so-called overlay inks that leave dyes on the recording paper surface to increase the print density. Since the overlay type was difficult to achieve water resistance, it contains an unsubstituted amino group. In general, when printing on paper, it is mainly affected by the surface pH of the paper, the pH of the ink on the paper is lowered, the amino group is cationized to ammonium, and this and the anion in the dye molecule It is presumed that the water resistance is ensured by aggregation and salt formation with the functional group.
[0005]
However, it is insufficient in terms of ink storage stability and ejection stability, and performance that satisfies market demands has not been obtained.
On the other hand, with recent color inks in color inkjet printers, there is also a new market demand for preventing the boundary between inks of different printed colors to mix (bleeding). Some penetrating inks are being developed. In other words, it is desired to have a sufficient performance as a quick-drying penetrating ink while ensuring the printing density.
[0006]
[Problems to be solved by the invention]
The present invention has good print quality even when recorded on plain paper, such as for inkjet recording and writing utensils, etc., and has a high recorded image density, excellent water resistance and light resistance, and is stored for a long time. It is an object of the present invention to provide a recording liquid having good stability in the case of the above.
[0007]
[Means for Solving the Problems]
The present inventors have achieved the present invention by confirming that, when a black dye having a specific structure is used as a recording liquid component, a performance satisfying the above-mentioned object can be obtained.
That is, the present invention contains at least one selected from the group consisting of a dye represented by the following general formula [I] and a dye represented by the following general formula [II] in the form of a free acid and an aqueous medium. The recording liquid is characterized by that.
[0008]
[Chemical 3]

[0009]
(In the general formula [I], A represents an optionally substituted phenylene group or naphthylene group, and V and W are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms, or a substituted group. Or an unsubstituted alkoxy group having 1 to 4 carbon atoms , wherein R ¹ , R ² and R ³ are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms, a substituted or unsubstituted group; Represents an amino group substituted with an alkoxy group having 1 to 4 carbon atoms, a hydroxyl group, a halogen atom, a carboxyl group, or an alkyl group having 1 to 4 carbon atoms or an acyl group having 2 to 12 carbon atoms , and R ⁴ and R ⁵ are And each independently represents a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms, l represents 1 or 2, and m represents 0 or 1.)
[0010]
[Formula 4]

[0011]
(In the general formula [II], B represents an optionally substituted phenylene group or naphthylene group, and X and Y are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms, or a substituted group. Or an unsubstituted alkoxy group having 1 to 4 carbon atoms , R ⁶ and R ⁷ each independently represents a hydrogen atom, a hydroxyl group, a nitro group, or a substituted or unsubstituted amino group, and R ⁸ and R ⁹ are each Independently represents a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms, n represents 1, 2, or 3, and p represents 0 or 1.)
[0012]
DETAILED DESCRIPTION OF THE INVENTION
The present invention is described in detail below.
The dye used in the present invention is represented by the general formula [I] or [II] in the first aspect. Specifically, in the general formula [I], the substituent of the phenylene group in A may have a substituent such as an alkoxy group having 1 to 4 carbon atoms, a hydroxyl group, or a hydroxyalkoxy group having 1 to 4 carbon atoms. A good alkyl group having 1 to 4 carbon atoms; an alkoxy group having 1 to 4 carbon atoms; an acylamino group such as an alkylcarbonylamino group having 2 to 6 carbon atoms and an arylcarbonylamino group having 7 to 12 carbon atoms; an SO ₃ H group; such as a carboxyl group, and examples of the substituent of the naphthylene group in a, SO ₃ H group, a carboxyl group, and the like alkoxy groups having 1 to 4 carbon atoms. Two or more substituents for A may be used.
[0013]
V and W preferably have a sum of 2 or more carbon atoms . Examples of the substituent of the alkyl group represented by V and W include a phenyl group, and the substituent of the alkoxy group includes an alkoxy group. , Hydroxyl group, phenyl group, benzyloxy group, carboxyl group and the like.
As for R ¹ , R ² and R ³ , examples of the substituent of the alkyl group include a hydroxyl group and an alkoxy group having 1 to 4 carbon atoms. Examples of the substituent of the alkoxy group include an alkoxy group having 1 to 4 carbon atoms. Can be mentioned. Examples of the substituent of the amino group include an alkyl group having 1 to 4 carbon atoms and an acyl group having 2 to 12 carbon atoms.
[0014]
Examples of the substituent for the alkyl group represented by R ⁴ and R ⁵ include an alkoxy group having 1 to 4 carbon atoms, a carboxyl group, and a hydroxyl group.
In the general formula [II], the substituent of the phenylene group in B may have a substituent such as an alkoxy group having 1 to 4 carbon atoms, a hydroxyl group, or a hydroxyalkoxy group having 1 to 4 carbon atoms. An alkyl group having 1 to 4 carbon atoms; an alkoxy group having 1 to 4 carbon atoms which may have a substituent such as an alkoxy group having 1 to 4 carbon atoms, a hydroxyl group, or a hydroxyalkoxy group having 1 to 4 carbon atoms; 6 alkylcarbonylamino groups, acylamino groups such as arylcarbonylamino groups having 7 to 12 carbon atoms; SO ₃ H groups; carboxyl groups, and the substituents of naphthylene groups in B include SO ₃ H groups, carboxyl groups And an alkoxy group having 1 to 4 carbon atoms. Two or more substituents for B may be used.
[0015]
X and Y preferably have 3 or more carbon atoms , and examples of the substituent of the alkyl group represented by X and Y include a phenyl group, and the substituent of the alkoxy group includes an alkoxy group. , Hydroxyl group, phenyl group, benzyloxy group, carboxyl group and the like.
In R ⁶ and R ⁷ , examples of the substituent of the amino group include an alkyl group having 1 to 4 carbon atoms and an acyl group having 2 to 12 carbon atoms.
[0016]
In R ⁸ and R ⁹ , examples of the substituent for the alkyl group include an alkoxy group having 1 to 4 carbon atoms, a carboxyl group, and a hydroxyalkyl group having 2 to 4 carbon atoms.
In the present invention, the dye represented by the general formula [I] or [II] may be a free acid form as represented by the general formula [I] or [II], but when it is obtained in a salt form after the production of the dye. May be used as is or formed into a desired salt form, or may be partly in acid form and part in salt form.
[0017]
Examples of those that form a salt in the case of such a salt form include alkali metals such as potassium, sodium, and lithium, and an ammonium group that may be substituted with an alkyl group having about 1 to 8 carbon atoms or a hydroxyalkyl group. And organic amines, which may be mixed. Among these, examples of organic amines are primary to tertiary substituted amines substituted with an organic group, lower alkylamines having about 1 to 4 carbon atoms, hydroxy-substituted lower alkylamines, carboxy-substituted lower alkylamines, and And polyamines having 2 to 10 alkyleneimine units having 2 to 4 carbon atoms.
Specific examples of these pigments include azo dyes having structures shown in the following I- (1) to I- (13) and II- (1) to II- (8).
[0018]
[Chemical formula 5]

[0019]
[Chemical 6]

[0020]
[Chemical 7]

[0021]
[Chemical 8]

[0022]
[Chemical 9]

[0023]
The azo dyes represented by the general formulas [I] and [II] are known per se [for example, see Hosoda Yutaka "New Dye Chemistry" (published December 21, 1973, Gihodo, pages 396-409)] Thus, it can be produced through a diazotization and coupling process.
The azo dye represented by the general formula [I] or [II] has a high Gram extinction coefficient (absorbance at the maximum absorption wavelength when the dye concentration in water is 1 g / l) as high as 50 to 120 and has good color developability. Regardless of whether the composition of the recording liquid is the above-described overlay type composition or the penetrating type composition, an image having a sufficient print density can be obtained.
[0024]
The content of the dye of the general formula [I] or [II] in the recording liquid is preferably about 0.5 to 12% by weight, particularly about 2 to 8% by weight, based on the total amount of the recording liquid.
In the present invention, one or more dyes represented by the above general formula [I] or [II] are used. In the case of a plurality, a plurality of types having the respective general formulas may be used, but one or more dyes having both general formulas may be used.
[0025]
Also, other known black pigments may be used in combination, or pigments of other color tones (for example, magenta, cyan, yellow) may be used in combination for color tone adjustment.
Examples of the aqueous medium used in the present invention include water and water-soluble organic solvents such as ethylene glycol, propylene glycol, butylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol (weight average molecular weight (Mw) = 190 to 400), glycerin. N-methylpyrrolidone, N-ethylpyrrolidone, 1,3-dimethylimidazolidinone, thiodiethanol, dimethyl sulfoxide, ethylene glycol monoallyl ether, ethylene glycol monomethyl ether, diethylene glycol monomethyl ether, diethylene glycol monobutyl ether, triethylene glycol monobutyl ether 2-pyrrolidone, sulfolane, ethyl alcohol, isopropyl alcohol, triethanolamine, etc. Preferably it has. These water-soluble organic solvents are usually used in the range of 1 to 50% by weight with respect to the total amount of the recording liquid. On the other hand, water is used in the range of 45 to 95% by weight with respect to the total amount of the recording liquid.
[0026]
0.1 to 10% by weight, preferably 0.5 to 5% by weight, of the compound selected from urea, thiourea, biuret and semicarbazide is added to the recording liquid of the present invention. By adding 001 to 5.0% by weight of a surfactant, quick drying after printing and printing quality can be further improved.
[0027]
The recording liquid of the present invention is black in itself and forms a black image. In addition, a multi-color or full-color image can be formed by using recording liquids of yellow, magenta and cyan in combination. it can. Specifically, for yellow, for example, C.I. I. Direct Yellow 86, 142, or 132, or C.I. I. For at least one of Acid Yellow 23 and the like, magenta, for example, C.I. I. Acid Red 35, 37, 52, 257, or 289, or C.I. I. As for at least one of Direct Red 80 and the like, cyan, for example, C.I. I. DirectBlue 86 or 199 or C.I. I. A recording liquid containing at least one dye such as Acid Blue 9 can be used in combination with the recording liquid of the present invention. The recording liquid other than black preferably has the same composition as that of the recording liquid of the present invention except that the above dye is used. That is, it contains an aqueous medium and various additives as required in addition to the above-mentioned pigment.
[0028]
The recording liquid of the present invention is suitable for use in inkjet recording, writing instruments, etc., but is particularly suitable for inkjet recording.
As the discharge means of the ink jet recording apparatus, one using electric energy, heat energy, or the like can be used.
[0029]
【Example】
EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, unless it exceeds the summary of this invention, it is not limited to these Examples.
Example 1
10 parts by weight of diethylene glycol, 3 parts by weight of isopropyl alcohol, Water was added to 3 parts by weight of the dye of I- (1), and the pH was adjusted to 9 with caustic soda water to make the total amount 100 parts by weight. This composition was sufficiently mixed and dissolved, pressure filtered through a Teflon filter having a pore size of 1 μm, and degassed with a vacuum pump and an ultrasonic cleaner to prepare a recording liquid.
[0030]
Using the obtained recording liquid, inkjet recording is performed on electrophotographic paper (product of Xerox Co., Ltd.) using an inkjet printer (trade name BJ-10V, product of Canon Inc.), and high density (1.35) black printing is performed. I got a thing. Further, various evaluations were performed by the following methods (a), (b), (c), (d) and (e). The results are shown in Table 1.
[0031]
(A) Light resistance of recorded image:
Using a xenon fade meter (product of Suga Test Instruments Co., Ltd.), the recording paper was irradiated for 100 hours. The fading color after irradiation was small.
(B) Water resistance of recorded image:
Water resistance test (1) Test method After immersing the recorded image in tap water for 5 minutes,
(1) The blur of the image was examined visually.
(2) The OD value (printing density) of the solid printing part before and after immersion was measured with a Macbeth densitometer (TR927).
(2) Test results As a result of the above (1), the blur of the image was slight.
The change in the density of the solid printing part before and after the immersion in the above (2) was 83.1% when expressed by the value of the OD residual rate according to the following formula.
[0032]
[Expression 1]
OD remaining ratio (%) = (OD value after immersion / OD value before immersion) × 100
[0033]
(C) Storage stability of recording liquid:
The recording liquid was sealed in a Teflon container and examined for changes after storage at 5 ° C. for 1 month and at 70 ° C. for 6 days. As a result, decomposition of the dye and precipitation of insoluble matter were not observed.
(D) Solubility In the preparation of the recording liquid described above, it was allowed to stand at room temperature for 1 day prior to pressure filtration with a Teflon filter having a pore diameter of 1 μm, and visually observed after pressure filtration. As a result, no filtration residue was observed on the filter.
[0034]
(E) Discharge stability:
Even in a room adjusted to an air temperature of 30 ° C. and a relative humidity of 20%, stable discharge was possible continuously for 3 hours.
In the evaluation of the above (a), (b), (c), (d) and (e), the visual judgment was evaluated in three stages: ○: good, Δ: somewhat inferior, ×: poor.
[0035]
Examples 2-4
The No. 1 used in Example 1 was used. In place of the dye of I-1, No. 1 mentioned above. I-2, No. 1 II-1 and no. A recording liquid was prepared by the method of Example 1 except that the dye of II-2 was used, respectively, and printing was performed using this to obtain a black recorded matter. Furthermore, various evaluations according to (a) to (e) of Example 1 were performed on the recorded matter. As a result, good results were obtained in the same manner as in Example 1. The OD residual ratios were 80.5%, 79.8%, and 84.2%, respectively. The results are shown in Table 1 below.
[0036]
Comparative Example 1
No. in the examples. In place of the dye of I-1, C.I. I. A composition was prepared using Food Black 2 in the same manner as in Example 1, and then processed to obtain a recording liquid. Using this recording liquid, printing was performed in the same manner as in Example 1 to obtain a black recorded matter. Various evaluations according to (a) to (e) of Example 1 were performed on the obtained recorded matter. The results are shown in Table 1 below.
[0037]
Comparative Example 2
No. 1 in Example 1. Dye No. 1 described in JP-A-7-207204 is used instead of the dye of I-1. (11) A composition was prepared using a dye of the following structural formula * 1 in the same manner as in Example 1, and then processed to obtain a recording liquid. Using this recording liquid, printing was performed in the same manner as in Example 1 to obtain a black recorded matter. Various evaluations according to (a) to (e) of Example 1 were performed on the obtained recorded matter. The results are shown in Table 1 below.
[0038]
Comparative Example 3
No. 1 in Example 1. Dye No. 1 described in JP-A-61-285276 is used in place of the dye of I-1. (1) Using the dye of the following structural formula * 2, a composition was prepared in the same manner as in Example 1 and then processed to obtain a recording liquid. Using this recording liquid, printing was performed in the same manner as in Example 1 to obtain a black recorded matter. Various evaluations according to (a) to (e) of Example 1 were performed on the obtained recorded matter. The results are shown in Table 1 below.
[0039]
[Chemical Formula 10]

[0040]
[Table 1]

[0041]
Example 5
10 parts by weight of glycerin, 5 parts by weight of diethylene glycol monobutyl ether, 5 parts by weight of 2-pyrrolidone, Water was added to 4.5 parts by weight of the pigment (II) -6, and the pH was adjusted to 9 with a 1% aqueous lithium hydroxide solution to make the total amount 100 parts by weight. A recording liquid was prepared by the method of Example 1, printed, and a black recorded product was obtained. Various evaluations according to (a) to (d) of Example 1 were performed on the recorded matter. As a result, similar to Example 1, good results were obtained.
[0042]
Examples 6-21
The No. 1 used in Example 1 was used. In place of the dye of I-1, No. 1 mentioned above. I- (3), no. I- (4), no. I- (5) to I- (13), no. II- (3) to (5) and No. 2 Using each of the dyes II- (7) to (8), a recording liquid was prepared by the method of Example 1 and printing was performed to obtain a black recorded matter. Various evaluations according to (a) to (e) of Example 1 were performed on the recorded matter. As a result, similar to Example 1, good results were obtained.
[0043]
【The invention's effect】
The recording liquid of the present invention is used for inkjet recording, writing instruments, etc., and when recorded on plain paper, a black-based recorded matter can be obtained, and its printing density, light resistance, and water resistance are excellent. In addition, the storage stability and ejection stability as a recording liquid are also good.

Claims (10)

A recording wherein the free acid form contains at least one selected from the group consisting of a dye represented by the following general formula [I] and a dye represented by the following general formula [II] and an aqueous medium liquid.

(In general formula [I], A represents an optionally substituted phenylene group or naphthylene group, and V and W are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms, or a substituted group. Or an unsubstituted alkoxy group having 1 to 4 carbon atoms , wherein R ¹ , R ² and R ³ are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms, a substituted or unsubstituted group; Represents an amino group substituted with an alkoxy group having 1 to 4 carbon atoms, a hydroxyl group, a halogen atom, a carboxyl group, or an alkyl group having 1 to 4 carbon atoms or an acyl group having 2 to 12 carbon atoms , and R ⁴ and R ⁵ are And each independently represents a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms, l represents 1 or 2, and m represents 0 or 1.)

(In the general formula [II], B represents an optionally substituted phenylene group or naphthylene group, and X and Y are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms, or Represents a substituted or unsubstituted alkoxy group having 1 to 4 carbon atoms , R ⁶ and R ⁷ each independently represents a hydrogen atom, a hydroxyl group, a nitro group, or a substituted or unsubstituted amino group, and R ⁸ and R ⁹ represent And each independently represents a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms, n represents 1, 2, or 3, and p represents 0 or 1.) The sum of the carbon numbers of V and W in the general formula [I] is 2 or more, and the general formula [I II The recording liquid according to claim 1, wherein the sum of the number of carbon atoms of X and Y is 3 or more. The dye represented by the general formula [I] or the general formula [ II The recording liquid according to claim 1, wherein the gram extinction coefficient of the dye represented by the formula is 50 to 120. The recording liquid according to claim 1, wherein the recording liquid is black. Dye represented by general formula (I) and / or general formula ( II The recording liquid according to claim 1, wherein the content of the dye represented by (1) is 0.5 to 12% by weight based on the total amount of the recording liquid. The recording liquid according to any one of claims 1 to 5, which is for inkjet recording. An ink jet recording method using the recording liquid according to claim 6. A recording liquid dye in which the form of the free acid is represented by the following general formula [I] or the following general formula [II].

(In general formula [I], A represents an optionally substituted phenylene group or naphthylene group, and V and W are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms, or a substituted group. Or an unsubstituted alkoxy group having 1 to 4 carbon atoms , wherein R ¹ , R ² and R ³ are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms, a substituted or unsubstituted group; Represents an amino group substituted with an alkoxy group having 1 to 4 carbon atoms, a hydroxyl group, a halogen atom, a carboxyl group, or an alkyl group having 1 to 4 carbon atoms or an acyl group having 2 to 12 carbon atoms , R ⁴ And R ⁵ each independently represents a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms, l represents 1 or 2, and m represents 0 or 1. )

(In the general formula [II], B represents an optionally substituted phenylene group or naphthylene group, and X and Y are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms, or Represents a substituted or unsubstituted alkoxy group having 1 to 4 carbon atoms , R ⁶ and R ⁷ each independently represents a hydrogen atom, a hydroxyl group, a nitro group, or a substituted or unsubstituted amino group, and R ⁸ and R ⁹ represent And each independently represents a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms, n represents 1, 2, or 3, and p represents 0 or 1.) The sum of the carbon numbers of V and W in the general formula [I] is 2 or more, and the general formula [I II The dye for recording liquid according to claim 8, wherein the sum of the carbon number of X and Y is 3 or more. The dye represented by the general formula [I] or the general formula [ II The dye for recording liquid according to claim 8 or 9, wherein the gram extinction coefficient of the dye represented by the formula is 50 to 120.