JP2013032469A - Aqueous black ink composition, inkjet recording method using the same and colored body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an aqueous black ink composition excellent in print density, light resistance, ozone resistance, moisture resistance, water resistance of recorded matter, and sensor-responsive characteristics when used for inkjet recording or writing utensils, and also good in storage stability as a recording liquid because of excellent dissolvability; and an inkjet recording method and a colored body using the composition.SOLUTION: This aqueous black ink composition contains a near infrared-absorptive iron tri(7-sulfo-3-nitroso-2-naphthoxide) or its salt as a pigment component. More preferably, the aqueous black composition includes a black dye expressed by chemical formula (2) or its salt in addition to the iron compound.

Description

  The present invention relates to an aqueous black ink composition, an ink jet recording method using the same, and a colored body.

A recording method using an ink jet printer, which is one of representative methods among various color recording methods, generates ink droplets and attaches them to various recording materials (paper, film, fabric, etc.) to perform recording. Is. This method has been spreading rapidly in recent years due to the fact that the recording head and the recording material are not in direct contact, so there is little noise and quietness, and it is easy to reduce the size and speed. Expected.
Conventionally, water-based inks in which water-soluble pigments are dissolved in an aqueous medium have been used as inks for fountain pens, felt-tip pens and the like and inks for ink jet printing. In these water-based inks, a water-soluble organic solvent is generally added to prevent clogging of the ink at the pen tip or the ink discharge nozzle. With these inks, it is possible to provide a recording image with sufficient density, no clogging of the pen tip and nozzles, good drying on the recording material, less bleeding, and storage stability. It is required to be excellent. In addition, the water-soluble dye used is required to have a particularly high solubility in water and a high solubility in a water-soluble organic solvent added to the ink. Furthermore, the formed image is required to have image fastness such as water resistance and light fastness and color reproducibility, and not only the image fastness is high but also the balance of each color is important.

  Due to the recent development of inkjet technology, the improvement in printing speed in inkjet printing is remarkable. For this reason, there is a movement to use an inkjet printer in the same manner as a laser printer using electronic toner for printing a document on plain paper, which is the main use in commercial printing and office environments. Ink jet printers have the advantage that the type of recording paper is not limited and the price of the machine is relatively low. In particular, ink jet printers are spreading in small to medium office environments such as SOHO. As described above, when an inkjet printer is used for printing on plain paper, color development and water resistance tend to be more important among qualities required for printed matter. In order to satisfy these performances, a method of using a pigment ink has been proposed. However, since the pigment ink is not a solution but a dispersion in which a solid pigment is dispersed, problems such as poor storage stability of the ink when the pigment ink is used, problems such as clogging of the nozzles of the printer head, etc. Is more likely to occur compared to dye inks. In addition, when pigment ink is used, it is often a problem that the printed image has low abrasion resistance. In the case of a dye ink, since the dye which is a pigment component is dissolved in the ink, problems caused by such a pigment ink are relatively unlikely to occur. However, since dye inks are generally significantly inferior to pigment inks in particular in terms of color developability, light resistance and water resistance, improvements are strongly desired.

  Furthermore, as one of the performances required in the commercial printing field, there is a light absorptivity (reflection characteristic) particularly in the near infrared light region outside the visible light region. This is because it is necessary to cope with reading of various sensors such as a near infrared light sensor.

  In addition to the above, the performance required for the ink composition for printing on plain paper includes color reproducibility (color development, ie, saturation and brightness), storage stability, and ozone resistance (oxidizing gas). Resistance), moisture resistance, and the like, and ink compositions that are sufficiently satisfactory in any of them have not been proposed yet.

  Therefore, in the future, in order to expand the field of use of printing methods using ink, the ink composition used for inkjet recording and the colored body colored thereby will have light resistance, ozone gas resistance, water resistance, moisture resistance. There is a strong demand for further improvements in sensor reading compatibility.

  Various hues of ink are prepared from various dyes, of which black ink is an important ink used for both monocolor and full color images. However, there are many technical difficulties in developing pigments that have neutral hues, high color densities, and excellent fastness in both the dark and light gamuts. Few have good performance. Therefore, generally, a black ink is prepared by mixing a plurality of various pigments. However, when an ink is prepared by mixing multiple dyes, the hue differs depending on the media (recording material) compared to the case of preparing an ink with a single dye. Problems such as increased discoloration are likely to occur.

  Many of the pigments proposed as dyes for black ink are azo pigments. I. Azo dyes such as Direct Black 19 have problems such as low optical density of the image, insufficient water resistance, light resistance and gas resistance. Similarly, some azo metal-containing dyes that have been proposed have good light resistance, but they contain metal ions, which is undesirable for safety and the environment for living organisms, and extremely low ozone gas resistance. There are problems such as. Many of these have been proposed, but have not yet been able to provide products that fully satisfy market demands.

  As black inks in which a dye for color adjustment is further blended with a black dye, for example, those disclosed in Patent Documents 1 to 3 have been proposed, but have not yet been provided with a product that sufficiently satisfies market demands.

  The dye used in the present invention is described in Patent Document 4, but there is no description regarding ink jet recording, and furthermore, it is not used for black toning.

  Examples of black colorants suitable for dye inks for inkjet recording include the above-described C.I. I. A compound of the formula (2) of the present application described in Direct Black 19 and Patent Document 6 is known.

Japanese Examined Patent Publication No. 7-122044 Patent No. 3178200 JP-A-9-255906 JP 2009-299249 A JP 2000-327941 A International Publication No. 2006/051850

  The present invention is stable even when stored in the form of a solution for a long time, exhibits neutral gray to black without color, and has optical density, fastness, light resistance, ozone gas resistance, and water resistance of the printed image. The object is to provide an aqueous black ink composition that gives an excellent black recorded image.

  As a result of intensive studies to solve the above-described problems, the present inventors have obtained a compound represented by the following formula (1), which is a specific dye as the dye component (component (I)) of the black ink. It has been found that an aqueous black ink composition having improved hue and various characteristics, and improved sensor compatibility in the near-infrared light region, can be obtained by using it. It is.

２）
更に、（Ｉ）色素成分として、（ｉｉ）分子内にアゾ結合（−Ｎ＝Ｎ−）を３つ以上有する染料を含有する上記１）に記載の水性黒色インク組成物、
３）
前記分子内にアゾ結合（−Ｎ＝Ｎ−）を３つ以上有する染料が下記式（２）で表される黒色染料またはその塩である上記２）に記載の水性黒色インク組成物、

（式（２）中、Ｒ¹、Ｒ²、Ｒ⁵、Ｒ⁶及びＲ⁷はそれぞれ独立して水素原子、ハロゲン原子、シアノ基、ヒドロキシ基、カルボキシ基、スルホ基、スルファモイル基、Ｎ−アルキルアミノスルホニル基、Ｎ−フェニルアミノスルホニル基、ヒドロキシ基で置換されても良い（Ｃ１〜Ｃ４）アルキルスルホニル基、ホスホ基、ニトロ基、アシル基、ウレイド基、（Ｃ１〜Ｃ４）アルキル基（ヒドロキシ基又は（Ｃ１〜Ｃ４）アルコキシ基で置換されていても良い）、（Ｃ１〜Ｃ４）アルコキシ基（ヒドロキシル基、（Ｃ１〜Ｃ４）アルコキシ基、スルホ基又はカルボキシ基で置換されていても良い）、アシルアミノ基、アルキルスルホニルアミノ基又はフェニルスルホニルアミノ基（ハロゲン原子、アルキル基又はニトロ基で置換されていても良い）を、Ｒ³及びＲ⁴はそれぞれ独立して水素原子、ハロゲン原子、シアノ基、カルボキシ基、スルホ基、ニトロ基、（Ｃ１〜Ｃ４）アルキル基（ヒドロキシ基または（Ｃ１〜Ｃ４）アルコキシ基で置換されていても良い）、（Ｃ１〜Ｃ４）アルコキシ基（ヒドロキシ基、（Ｃ１〜Ｃ４）アルコキシ基、スルホ基又はカルボキシ基で置換されていても良い）、アシルアミノ基、アルキルスルホニルアミノ基又はフェニルスルホニルアミノ基（ハロゲン原子、アルキル基又はニトロ基で置換されても良い）を、ｎは０または１をそれぞれ表す。）
４）
式（２）中、Ｒ¹がカルボキシ基又はスルホ基、Ｒ²が水素原子、Ｒ⁶がカルボキシ基又はスルホ基であり、ｎが１である上記３）に記載の水性黒色インク組成物、
５）
Ｒ¹がスルホ基であり、Ｒ¹の置換位置がアゾ基に対しオルト位の場合、ニトロ基の置換位置がアゾ基に対しパラ位であり、Ｒ¹の置換位置がアゾ基に対しパラ位の場合、ニトロ基の置換位置がアゾ基に対しオルト位である上記３）又は４）に記載の水性黒色インク組成物、
６）
Ｒ³がスルホ基、Ｒ⁴が水素原子、Ｒ⁵が水素原子又はカルボキシ基又はスルホ基、Ｒ⁷が水素原子である上記３）乃至５）のいずれか一項に記載の水性黒色インク組成物、
７）
前期式（２）で表される黒色染料が、下記式（３）で表される黒色染料またはその塩である上記３）に記載の水性黒色インク組成物、

（式（３）中、Ｒ¹はスルホ基でありＲ¹の置換位置がアゾ基に対しオルト位の場合、ニトロ基の置換位置がアゾ基に対しパラ位であり、Ｒ¹の置換位置がアゾ基に対しパラ位の場合、ニトロ基の置換位置がアゾ基に対しオルト位である。）
８）
更に、（Ｉ）色素成分として、（ｉｉｉ）Ｃ．Ｉ． Ｄｉｒｅｃｔ Ｙｅｌｌｏｗ ８６、１３２、１４２、Ｃ．Ｉ． Ｄｉｒｅｃｔ Ｏｒａｎｇｅ １７、３９、Ｃ．Ｉ． Ｄｉｒｅｃｔ Ｒｅｄ ８０、２２７、Ｃ．Ｉ． Ｄｉｒｅｃｔ Ｂｒｏｗｎ １０６、Ｃ．Ｉ． Ａｃｉｄ Ｏｒａｎｇｅ ９５、Ｃ．Ｉ． Ａｃｉｄ Ｒｅｄ ２４９、２５４から選択される１又は２以上の染料を含有する上記２）乃至７）のいずれか一項に記載の水性黒色インク組成物、
９）
（Ｉ）色素成分総質量中、前記（ｉ）を５〜４０質量％、前記（ｉｉ）を２０〜８０質量％、（ｉｉｉ）を１０〜６０質量％含有する請求項８に記載の水性黒色インク組成物、
１０）
更に（ＩＩ）水溶性有機溶剤を含有する上記１）乃至９）のいずれか一項に記載の水性黒色インク組成物、
１１）
更に（ＩＩＩ）尿素を含有する上記１）乃至１０）のいずれか一項に記載の水性黒色インク組成物、
１２）
上記１）乃至１１）のいずれか一項に記載の水性黒色インク組成物を用いるインクジェット記録方法、
１３）
インクジェット記録方法における被記録材が情報伝達用シートである上記１２）に記載のインクジェット記録方法、
１４）
上記１）乃至１１）のいずれか一項に記載の水性黒色インク組成物を含む容器を装填したインクジェットプリンタ、
１５）
上記１）乃至１１）のいずれか一項に記載の水性黒色インク組成物で着色された着色体、
に関する。 That is, the present invention
1)
(I) a water-based black ink composition comprising, as a dye component, (i) a water-soluble compound represented by the following formula (1) or a salt thereof,

2)
And (ii) a water-based black ink composition as described in 1) above, wherein the dye component contains (ii) a dye having three or more azo bonds (-N = N-) in the molecule;
3)
The aqueous black ink composition according to 2) above, wherein the dye having three or more azo bonds (—N═N—) in the molecule is a black dye represented by the following formula (2) or a salt thereof:

(In the formula (2), R ¹ , R ² , R ⁵ , R ⁶ and R ⁷ are each independently a hydrogen atom, halogen atom, cyano group, hydroxy group, carboxy group, sulfo group, sulfamoyl group, N-alkyl. Aminosulfonyl group, N-phenylaminosulfonyl group, (C1-C4) alkylsulfonyl group, phospho group, nitro group, acyl group, ureido group, (C1-C4) alkyl group (hydroxy group) which may be substituted with hydroxy group Or (C1-C4) which may be substituted with an alkoxy group), (C1-C4) alkoxy group (which may be substituted with a hydroxyl group, a (C1-C4) alkoxy group, a sulfo group or a carboxy group), An acylamino group, an alkylsulfonylamino group or a phenylsulfonylamino group (even if it is substituted with a halogen atom, an alkyl group or a nitro group) R ³ and R ⁴ are each independently a hydrogen atom, halogen atom, cyano group, carboxy group, sulfo group, nitro group, (C1-C4) alkyl group (hydroxy group or (C1-C4) alkoxy group) Or (C1-C4) alkoxy group (which may be substituted with a hydroxy group, (C1-C4) alkoxy group, sulfo group or carboxy group), an acylamino group, an alkylsulfonylamino group, or A phenylsulfonylamino group (which may be substituted with a halogen atom, an alkyl group or a nitro group), n represents 0 or 1, respectively)
4)
In the formula (2), R ¹ is a carboxy group or a sulfo group, R ² is a hydrogen atom, R ⁶ is a carboxy group or a sulfo group, and n is 1, the water-based black ink composition according to 3) above,
5)
When R ¹ is a sulfo group and the substitution position of R ¹ is ortho to the azo group, the substitution position of the nitro group is para to the azo group, and the substitution position of R ¹ is para to the azo group In this case, the water-based black ink composition according to the above 3) or 4), wherein the substitution position of the nitro group is ortho to the azo group,
6)
The aqueous black ink composition according to any one of 3) to 5) above, wherein R ³ is a sulfo group, R ⁴ is a hydrogen atom, R ⁵ is a hydrogen atom, a carboxy group or a sulfo group, and R ⁷ is a hydrogen atom. ,
7)
The aqueous black ink composition according to 3), wherein the black dye represented by the previous formula (2) is a black dye represented by the following formula (3) or a salt thereof,

(In the formula (3), when R ¹ is a sulfo group and the substitution position of R ¹ is ortho to the azo group, the substitution position of the nitro group is para to the azo group, and the substitution position of R ¹ is (In the case of para position to the azo group, the substitution position of the nitro group is ortho position to the azo group.)
8)
Furthermore, (iii) C.I. I. Direct Yellow 86, 132, 142, C.I. I. Direct Orange 17, 39, C.I. I. Direct Red 80, 227, C.I. I. Direct Brown 106, C.I. I. Acid Orange 95, C.I. I. The water-based black ink composition according to any one of 2) to 7) above, which contains one or more dyes selected from Acid Red 249, 254,
9)
(I) The aqueous black according to claim 8, comprising 5 to 40% by mass of (i), 20 to 80% by mass of (ii), and 10 to 60% by mass of (iii) in the total mass of the pigment component. An ink composition,
10)
(II) The water-based black ink composition according to any one of 1) to 9) above, which contains a water-soluble organic solvent,
11)
(III) The aqueous black ink composition according to any one of 1) to 10) above, which contains urea;
12)
An inkjet recording method using the water-based black ink composition according to any one of 1) to 11) above;
13)
The inkjet recording method according to 12) above, wherein the recording material in the inkjet recording method is an information transmission sheet,
14)
An inkjet printer loaded with a container containing the aqueous black ink composition according to any one of 1) to 11) above;
15)
A colored body colored with the water-based black ink composition according to any one of 1) to 11) above;
About.

The aqueous black ink composition of the present invention has good storage stability without crystal precipitation, physical property change, color change and the like after long-term storage. Further, the aqueous black ink composition of the present invention is used for ink jet recording, writing instruments, etc., and prepares an ink having a low dye concentration and a neutral hue of a recorded image when recorded on plain paper and ink jet dedicated paper. Even in this case, a printed matter with a black hue can be obtained. In addition, the print density is high, and it is excellent in light resistance, ozone gas resistance, moisture resistance, water resistance, and near infrared light sensor compatibility.
Further, when used together with magenta, cyan and yellow dyes, full color ink jet recording excellent in high color development, light resistance, ozone gas resistance and water resistance is possible. Thus, the ink composition of the present invention is extremely useful as a black ink for inkjet recording.

The present invention will be described in detail.
The aqueous black ink composition of the present invention contains (i) a water-soluble compound represented by the above formula (1) or a salt thereof as the dye component (I). By containing this compound, compared with the conventional black ink composition, the hue and the sensor correspondence particularly in the near-infrared light region can be remarkably improved.

  The compound represented by the above formula (1) or a salt thereof is a water-soluble dye. In the present specification, unless otherwise specified, acidic functional groups such as sulfo groups and carboxy groups are represented in the form of free acids. Further, as described above, the present invention includes both the compound represented by the formula (1) or a salt of the compound, and both of them are always referred to as “the compound represented by the formula (1) or a salt thereof” and the like. This is complicated. For this reason, unless otherwise specified, for convenience, both are simply described as “compound represented by formula (1)” and described below.

  The compound represented by the above formula (1) is C.I. I. It is a compound known as Acid Green 1, and can be obtained from Tokyo Chemical Industry Co., Ltd. as a dye for biochemical use.

  The salt of the compound represented by the formula (1) means an inorganic or organic cation salt independently. Among these, specific examples of inorganic salts include alkali metal salts, alkaline earth metal salts, and ammonium salts. Preferred inorganic salts are lithium, sodium, potassium salts, and ammonium salts. Examples of organic cation salts include, but are not limited to, salts of compounds represented by the following general formula (4).

The alkyl group of Z ¹ , Z ² , Z ³ and Z ^{4 in} the general formula (4) is preferably a (C1 to C4) alkyl group, and specific examples include methyl, ethyl, n-propyl, isopropyl, n-butyl, Examples include isobutyl, sec-butyl, tert-butyl and the like.
Examples of hydroxyalkyl groups include hydroxy- (C1-C4) alkyl groups such as hydroxymethyl, hydroxyethyl, 3-hydroxypropyl, 2-hydroxypropyl, 4-hydroxybutyl, 3-hydroxybutyl, 2-hydroxybutyl and the like. It is done.
Examples of hydroxyalkoxyalkyl groups include hydroxyethoxymethyl, 2-hydroxyethoxyethyl, 3-hydroxyethoxypropyl, 2-hydroxyethoxypropyl, 4-hydroxyethoxybutyl, 3-hydroxyethoxybutyl, 2-hydroxyethoxybutyl, etc. A hydroxy (C1-C4) alkoxy- (C1-C4) alkyl group is mentioned, Among these, a hydroxyethoxy- (C1-C4) alkyl group is preferable. Particularly preferred is a hydrogen atom; methyl; hydroxy- (C1-C4) alkyl such as hydroxymethyl, hydroxyethyl, 3-hydroxypropyl, 2-hydroxypropyl, 4-hydroxybutyl, 3-hydroxybutyl, 2-hydroxybutyl, etc. Groups: hydroxyethoxy- (C1-C4) such as hydroxyethoxymethyl, 2-hydroxyethoxyethyl, 3-hydroxyethoxypropyl, 2-hydroxyethoxypropyl, 4-hydroxyethoxybutyl, 3-hydroxyethoxybutyl, 2-hydroxyethoxybutyl, etc. ) Alkyl group.

Specific examples of Z ¹ , Z ² , Z ³ and Z ^{4 in} the general formula (4) are shown in Table 1 below.

  Preferable examples of the organic cation salt include monoethanolamine salt, diethanolamine salt, triethanolamine salt, monoisopropanolamine salt, diisopropanolamine salt, and triisopropanolamine salt.

  Of the above inorganic and organic cation salts, lithium and sodium salts are particularly preferred.

  The black ink composition of the present invention can be made black by blending various dyes other than the compound of the above formula (1) as the pigment component (I). In particular, the azo bond (—N The dye (ii) having three or more = N-) is preferred. When the dye is used, a black ink composition having excellent water resistance and light resistance can be obtained. Further, it is particularly preferable to use a black dye having three or more azo bonds (—N═N—) in the molecule as the dye, and the black dye represented by the above formula (2) is used as the black dye. In this case, it is possible to achieve both color developability, light resistance, ozone resistance, and water resistance, and an extremely excellent aqueous black ink composition can be realized.

  In the black dye represented by the above formula (2), the number of carbon atoms in the alkyl group, alkoxy group, acyl group and the like not particularly described is not particularly limited as long as the effects of the present invention can be achieved. Usually, it has about 1 to 20 carbon atoms, preferably about 1 to 10 carbon atoms, more preferably about 1 to 4 carbon atoms in the case of an alkyl group, an alkoxy group or an aliphatic acyl group. In the case of an acyl group, it has 7 to 11 carbon atoms, and specific examples include a benzoyl group and a naphthoyl group.

In R < ¹ >, R < ² >, R < ⁵ >, R < ⁶ > and R < ⁷ > in the above formula (2), examples of the N-alkylaminosulfonyl group include N-methylaminosulfonyl group, N-ethylaminosulfonyl group, N- (N-butyl) aminosulfonyl group, N, N-dimethylaminosulfonyl group, N, N-di (n-propyl) aminosulfonyl group and the like can be mentioned.

In R ¹ , R ² , R ⁵ , R ⁶ and R ⁷ in the above formula (2), examples of the (C1-C4) alkylsulfonyl group which may be substituted with a hydroxy group include, for example, methylsulfonyl, ethylsulfonyl, Examples include propylsulfonyl, butylsulfonyl, hydroxyethylsulfonyl, 2-hydroxypropylsulfonyl and the like.

In R ¹ , R ² , R ⁵ , R ⁶ and R ⁷ in the above formula (2), examples of the acyl group include acetyl, propionyl, butyryl, isobutyryl, benzoyl, naphthoyl and the like.

Examples of (C1-C4) alkyl group which may be substituted with a hydroxy group or a (C1-C4) alkoxy group in R ¹ to R ⁷ in the above formula (2) include, for example, methyl, ethyl, n-propyl, Isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, 2-hydroxyethyl, 2-hydroxypropyl, 3-hydroxypropyl, methoxyethyl, 2-ethoxyethyl, n-propoxyethyl, isopropoxyethyl, n- Examples include butoxyethyl, methoxypropyl, ethoxypropyl, n-propoxypropyl, isopropoxybutyl, n-propoxybutyl and the like.

In R ¹ to R ⁷ in the above formula (2), examples of the (C1-C4) alkoxy group which may be substituted with a hydroxy group, a (C1-C4) alkoxy group, a sulfo group or a carboxy group include, for example, methoxy, Ethoxy, n-propoxy, isopropoxy, n-butoxy, sec-butoxy, tert-butoxy, 2-hydroxyethoxy, 2-hydroxypropoxy, 3-hydroxypropoxy, methoxyethoxy, ethoxyethoxy, n-propoxyethoxy, isopropoxyethoxy N-butoxyethoxy, methoxypropoxy, ethoxypropoxy, n-propoxypropoxy, isopropoxybutoxy, n-propoxybutoxy, 2-hydroxyethoxyethoxy, carboxymethoxy, 2-carboxyethoxy, 3-carboxyprop Poxy, 3-sulfopropoxy, 4-sulfobutoxy and the like can be mentioned.

In R ¹ to R ⁷ in the above formula (2), examples of the acylamino group include acetylamino, propionylamino, butyrylamino, isobutyrylamino, benzoylamino, naphthoylamino and the like.

In R ¹ to R ⁷ in the above formula (2), examples of the alkylsulfonylamino group include methylsulfonylamino, ethylsulfonylamino, propylsulfonylamino and the like.

Examples of the phenylsulfonylamino group which may be substituted with a halogen atom, an alkyl group or a nitro group in R ¹ to R ⁷ in the above formula (2) include, for example, benzenesulfonylamino, toluenesulfonylamino, chlorobenzenesulfonylamino, nitrobenzene And sulfonylamino.

Preferred R ¹ and R ² in the above formula (2) are a hydrogen atom, a chlorine atom, a bromine atom, a cyano group, a carboxy group, a sulfo group, a sulfamoyl group, an N-methylaminosulfonyl group, an N-phenylaminosulfonyl group, a methyl group. Sulfonyl group, hydroxyethylsulfonyl group, phosphate group, nitro group, acetyl group, benzoyl group, ureido group, methyl group, methoxy group, ethyl group, ethoxy group, propyl group, propoxy group, 2-hydroxyethoxy group, 2- A methoxyethoxy group, a 2-ethoxyethoxy group, a 3-sulfopropoxy group, a 4-sulfobutoxy group, a carboxymethoxy group, a 2-carboxyethoxy group, an acetylamino group, a benzoylamino group, and more preferably a hydrogen atom, Chlorine atom, cyano group, sulfamoyl group, acetyl group, nitro group, A carboxy group and a sulfo group are preferable, and a hydrogen atom, a carboxy group, and a sulfo group are more preferable.
Further preferred R ¹ is a carboxy group or a sulfo group, and a sulfo group is particularly preferred. R ² is particularly preferably a hydrogen atom.
When the substitution position of R ¹ is ortho to the azo group, the substitution position of the nitro group is para to the azo group, and when the substitution position of R ¹ is para to the azo group, The substitution position of the group is preferably ortho to the azo group.

Preferred R ³ and R ⁴ in the above formula (2) are hydrogen atom, cyano group, carboxy group, sulfo group, nitro group, methyl group, methoxy group, ethyl group, ethoxy group, propyl group, propoxy group, 2-hydroxy group. An ethoxy group, a 2-methoxyethoxy group, a 2-ethoxyethoxy group, a 3-sulfopropoxy group, a 4-sulfobutoxy group, a carboxymethoxy group, a 2-carboxyethoxy group, and an acetylamino group, more preferably a hydrogen atom, They are a carboxy group, a sulfo group, a methyl group, a methoxy group, and a 3-sulfopropoxy group, and more preferably a hydrogen atom and a sulfo group. A combination in which R ³ is a sulfo group and R ⁴ is a hydrogen atom is particularly preferable.

Preferred R ⁵ to R ⁷ in the above formula (2) are hydrogen atom, chlorine atom, bromine atom, cyano group, carboxy group, sulfo group, sulfamoyl group, N-methylaminosulfonyl group, N-phenylaminosulfonyl group, methyl Sulfonyl group, hydroxyethylsulfonyl group, phosphate group, nitro group, acetyl group, benzoyl group, ureido group, methyl group, methoxy group, ethyl group, ethoxy group, propyl group, propoxy group, 2-hydroxyethoxy group, 2- A methoxyethoxy group, a 2-ethoxyethoxy group, a 3-sulfopropoxy group, a 4-sulfobutoxy group, a carboxymethoxy group, a 2-carboxyethoxy group, an acetylamino group, a benzoylamino group, and more preferably a hydrogen atom, Chlorine atom, cyano group, sulfamoyl group, acetyl group, nitro group, A carboxy group and a sulfo group are preferable, and a hydrogen atom, a carboxy group, and a sulfo group are more preferable.
Particularly preferred R ⁵ is a hydrogen atom, a carboxy group or a sulfo group, particularly preferred R ⁶ is a carboxy group or a sulfo group, and particularly preferred R ⁷ is a hydrogen atom.

Regarding the black dye represented by the above formula (2), R ¹ to R ⁷ are more preferably a combination of the substituents mentioned as the above preferable ones, more preferably a combination of a preferable substituent and a more preferable substituent. A combination of substituents is most preferred.

  As the black dye represented by the above formula (2), the most preferable one is the black dye represented by the above formula (3), which is particularly effective for light resistance, ozone resistance and water resistance.

  Both of the black dye represented by the above formula (2) and the black dye represented by the above formula (3) can be used as a salt thereof as well as the compound represented by the above formula (1). The salt in this case is the same as that of the compound of the above formula (1), including preferred ones.

  The black dye represented by the above formula (2) can be synthesized, for example, by the following method. The structural formula of the compound in each step is expressed in the form of a free acid.

（式中ｎは上記式（２）と同じ意味を有する。）
とｐ−トルエンスルホニルクロライドとのアルカリ存在下での反応により得られる下記式（６） Following formula (5)

(In the formula, n has the same meaning as in the above formula (2).)
And the following formula (6) obtained by the reaction of p-toluenesulfonyl chloride with an alkali.

（式中ｎは上記式（２）と同じ意味を有する。）
で表される化合物を、常法によりジアゾ化し、４−アミノ−５−ナフトール−１,７−ジスルホン酸と酸性下カップリング反応し、生成した下記式（７）

(In the formula, n has the same meaning as in the above formula (2).)
The compound represented by the following formula (7) was produced by diazotization by a conventional method, and a coupling reaction with 4-amino-5-naphthol-1,7-disulfonic acid under acidic conditions.

（式中ｎは上記式（２）と同じ意味を有する。）
で表される化合物に、式（８）

(In the formula, n has the same meaning as in the above formula (2).)
A compound represented by formula (8):

（式中Ｒ¹及びＲ²は上記式（２）と同じ意味を有する。）
で表される化合物を常法によりジアゾ化したものをカップリング反応させ、得られる式（９）

(In the formula, R ¹ and R ² have the same meaning as in the above formula (2).)
A compound obtained by diazotizing a compound represented by formula (9) by a coupling reaction is obtained, and the resulting formula (9)

（式中Ｒ¹、Ｒ²及びｎは上記式（２）と同じ意味を有する。）
で表される化合物をアルカリ条件下、加水分解し、式（１０）

(Wherein R ¹ , R ² and n have the same meaning as in the above formula (2).)
The compound represented by formula (10) is hydrolyzed under alkaline conditions.

(Wherein R ¹ , R ² and n have the same meaning as described above.)
To obtain a compound represented by: Here, the following formula (11)

（式中Ｒ³〜Ｒ⁷は上記式（２）と同じ意味を有する。）
で表されるモノアゾ化合物を常法によりジアゾ化したものを、カップリング反応させる事で、上記式（２）又は（３）で表される黒色染料またはその塩を得ることができる。

(Wherein R ^{3 to} R ⁷ have the same meaning as in the above formula (2).)
A black dye represented by the above formula (2) or (3) or a salt thereof can be obtained by subjecting a monoazo compound represented by general formula (II) to diazotization by a conventional method to a coupling reaction.

（式中Ｒ⁵、Ｒ⁶及びＲ⁷は上記式（２）と同じ意味を有する。）
で表される化合物を常法によりジアゾ化したものと下記式（１３） The monoazo compound of the above formula (11) can be synthesized by a conventional method. For example, the following formula (12)

(Wherein R ⁵ , R ⁶ and R ⁷ have the same meaning as in the above formula (2).)
And a compound represented by the following formula (13):

（式中Ｒ³及びＲ⁴は上記式（２）と同じ意味を有する。）
で表される化合物とカップリング反応させるか、或いは下記式（１４）

(Wherein R ³ and R ⁴ have the same meaning as in the above formula (2).)
Or a coupling reaction with a compound represented by the following formula (14)

(Wherein R ³ and R ⁴ have the same meaning as in the above formula (2).)
And a compound of the formula (15):

（式中Ｒ⁵〜Ｒ⁷は上記式（２）と同じ意味を有する。）
で表される化合物とカップリング反応させた下記式（１６）

(Wherein R ^{5 to} R ⁷ have the same meaning as in the above formula (2).)
The following formula (16) wherein a coupling reaction with a compound represented by the formula:

（式中Ｒ³〜Ｒ⁷は上記式（２）と同じ意味を有する。）
で表される化合物を酸性或いはアルカリ性で加水分解する事によって得ることができる。

(Wherein R ^{3 to} R ⁷ have the same meaning as in the above formula (2).)
It can obtain by hydrolyzing the compound represented by acidic or alkaline.

  The esterification reaction between the compound of formula (5) and p-toluenesulfonyl chloride is carried out by a method known per se, and is carried out in water or a water-soluble organic solvent, for example at a temperature of 20 to 100 ° C., preferably 30 to 80 ° C. It is advantageous to carry out at a neutral to alkaline pH value. It is preferably carried out at a neutral to weakly alkaline pH value, for example, pH 7-10. The pH value is adjusted by adding a base. Examples of the base include alkali metal hydroxides such as lithium hydroxide and sodium hydroxide, alkali metal carbonates such as lithium carbonate, sodium carbonate and potassium carbonate, and acetates such as sodium acetate. The compound of formula (5) and p-toluenesulfonyl chloride are used in approximately stoichiometric amounts.

  The diazotization of the compound of the formula (6) is carried out in a manner known per se, for example nitrites, such as sodium nitrite, in an inorganic acid medium, for example at a temperature of −5 to 30 ° C., preferably 5 to 15 ° C. It is carried out using an alkali metal nitrite salt. Coupling of the diazotized compound of formula (6) with 4-amino-5-naphthol-1,7-disulfonic acid is also carried out under conditions known per se. It is advantageous to carry out the reaction in water or a water-soluble organic solvent, for example at a temperature of -5 to 30 ° C, preferably 5 to 25 ° C and an acidic to neutral pH value. The coupling bath is acidified but is preferably carried out at an acidic to slightly acidic pH value, for example pH 1-4. The pH value is adjusted by adding a base. Examples of the base that can be used include alkali metal hydroxides such as lithium hydroxide and sodium hydroxide, alkali metal carbonates such as lithium carbonate, sodium carbonate and potassium carbonate, acetates such as sodium acetate, ammonia and organic amines. . The compound of formula (6) and 4-amino-5-naphthol-1,7-disulfonic acid are used in approximately stoichiometric amounts.

  The diazotization of the compound of formula (8) is also carried out in a manner known per se, for example a subnitrite such as nitrite, for example sodium nitrite, in an inorganic acid medium, for example at a temperature of -5 to 30 ° C, preferably 0 to 15 ° C. It is carried out using an alkali metal nitrate. Coupling of the diazotized compound of the compound of formula (8) and the compound of formula (7) is also carried out under conditions known per se. It is advantageous to carry out the reaction in water or a water-soluble organic solvent, for example at a temperature of -5 to 30 ° C, preferably 10 to 25 ° C, and a weakly acidic to alkaline pH value. It is preferably carried out at a weakly acidic to weakly alkaline pH value, for example, pH 5 to 10, and the pH value is adjusted by adding a base. Examples of bases that can be used include alkali metal hydroxides such as lithium hydroxide and sodium hydroxide, alkali metal carbonates such as lithium carbonate, sodium carbonate and potassium carbonate, acetates such as sodium acetate, and ammonia or organic amines. it can. The compounds of formulas (7) and (8) are used in approximately stoichiometric amounts.

  Production of the compound of the general formula (10) by hydrolysis of the compound of the formula (9) is also carried out by a method known per se. The heating is preferably performed in an aqueous alkaline medium. For example, after adding sodium hydroxide or potassium hydroxide to a solution containing the compound of the general formula (9) to adjust the pH to 9.5 or higher, for example, 20 to 150 It is carried out by heating to a temperature of ° C., preferably 30 to 100 ° C. At this time, the pH value of the reaction solution is preferably maintained at 9.5 to 11.5. The pH value is adjusted by adding a base. As the base, those described above can be used.

  The diazotization of the compound of formula (11) is also carried out in a manner known per se, for example a subnitrite such as nitrite, for example sodium nitrite, in an inorganic acid medium, for example at a temperature of -5 to 30 ° C, preferably 0 to 15 ° C. It is carried out using an alkali metal nitrate. Coupling of the diazotized compound of the compound of formula (11) and the compound of formula (10) is also carried out under conditions known per se. It is advantageous to carry out the reaction in water or a water-soluble organic solvent, for example at a temperature of -5 to 30 ° C, preferably 10 to 25 ° C, and a weakly acidic to alkaline pH value. It is preferably carried out at a weakly acidic to weakly alkaline pH value, for example, pH 5 to 10, and the pH value is adjusted by adding a base. Examples of bases that can be used include alkali metal hydroxides such as lithium hydroxide and sodium hydroxide, alkali metal carbonates such as lithium carbonate, sodium carbonate and potassium carbonate, acetates such as sodium acetate, and ammonia or organic amines. it can. The compounds of formulas (10) and (11) are used in approximately stoichiometric amounts.

  The black dye represented by the above formula (2) or (3) can be isolated in the form of a free acid by adding a mineral acid after the coupling reaction, and from this, the inorganic salt is washed by washing with water or acidified water. Can be removed. Next, the acid type dye having a low salt content thus obtained can be neutralized with a desired inorganic or organic base in an aqueous medium to obtain a solution of the corresponding salt. Examples of inorganic bases include, for example, alkali metal hydroxides such as lithium hydroxide, sodium hydroxide, and potassium hydroxide, ammonium hydroxide, or alkali metal carbonates such as lithium carbonate, sodium carbonate, and potassium carbonate. Examples of the organic base include, but are not limited to, organic amines such as alkanolamines such as diethanolamine and triethanolamine.

  Suitable specific examples of the compound represented by the above formula (2) are listed in Tables 2 to 4. However, the compound represented by the above formula (2) is not particularly limited thereto.

  The aqueous black ink composition of the present invention comprises (i) 0.1 to 10% by mass, preferably 0.5 to 5% by mass, more preferably 1 to 4% by mass of the compound represented by the above formula (1). An ink composition containing water as a main medium. In addition, when (ii) the compound represented by the above formula (2) or (3) is contained as a black dye, 0.1 to 20% by mass, preferably 1 to 10% by mass, more preferably 2 to 2%. 8% by mass is contained.

  When the black ink composition of the present invention is used as an ink for an ink jet printer, the compound represented by the above formula (1) and the compounds represented by the above formulas (2) and (3) may be metal cations. It is preferable to use a material having a small content of inorganic substances such as chlorides and sulfates, and the standard of the content is, for example, about 1% by mass or less (to the chromogen). In order to produce the compound of the present invention with a small amount of inorganic substances, for example, a conventional method using a reverse osmosis membrane or a dried product or wet cake of the compound of the present invention is stirred in a mixed solvent of alcohol such as methanol and water, and filtered. Desalting treatment may be performed by a method such as drying.

  The aqueous black ink composition of the present invention may further contain a dye (iii) having another hue for the purpose of adjusting the color tone. The other dye is preferably a reactive dye, an acid dye, or a direct dye, and more preferably a direct dye, from the viewpoint of dyeing properties of the dye on the recording material.

  Specific examples of the reactive dye contained in the aqueous black ink composition of the present invention include C.I. I. Yellow dyes such as Reactive Yellow 2, 3, 18, 81, 84, 85, 95, 99, 102; I. Orange dyes such as Reactive Orange 5, 9, 12, 13, 35, 45, 99; I. Brown dyes such as Reactive Brown 2, 8, 9, 17, 33; I. Red dyes such as Reactive Red 3, 3: 1, 4, 13, 24, 29, 31, 33, 125, 151, 206, 218, 226, 245; I. Violet dyes such as Reactive Violet 1, 24; I. Blue dyes such as Reactive Blue 2, 5, 10, 13, 14, 15, 15: 1, 49, 63, 71, 72, 75, 162, 176; I. Green dyes such as Reactive Green 5, 8, 19; I. And black dyes such as Reactive Black 1, 8, 23, 39, and the like.

  Specific examples of the acid dye contained in the aqueous black ink composition of the present invention include C.I. I. Acid Yellow 1, 3, 11, 17, 18, 19, 23, 25, 36, 38, 40, 40: 1, 42, 44, 49, 59, 59: 1, 61, 65, 72, 73, 79, Yellow dyes such as 99, 104, 110, 159, 169, 176, 184, 193, 200, 204, 207, 215, 219, 219: 1, 220, 230, 232, 235, 241, 242, 246; C. I. Acid Orange 3, 7, 8, 10, 19, 24, 51, 56, 67, 74, 80, 86, 87, 88, 89, 94, 95, 107, 108, 116, 122, 127, 140, 142, Orange dyes such as 144, 149, 152, 156, 162, 166, 168; I. Acid Brown 2, 4, 13, 14, 19, 28, 44, 123, 224, 226, 227, 248, 282, 283, 289, 294, 297, 298, 301, 355, 357, 413, etc. A dye; I. Acid Red 1, 6, 8, 9, 13, 18, 27, 35, 37, 52, 54, 57, 73, 82, 88, 97, 97: 1, 106, 111, 114, 118, 119, 127, 131, 138, 143, 145, 151, 183, 195, 198, 211, 215, 217, 225, 226, 249, 251, 254, 256, 257, 260, 261, 264, 265, 266, 274, 276, Red dyes such as 277, 289, 296, 299, 315, 318, 336, 337, 357, 359, 361, 362, 364, 366, 399, 407, 415; I. Violet dyes such as Acid Violet 17, 19, 21, 42, 43, 47, 48, 49, 54, 66, 78, 90, 97, 102, 109, 126; I. Acid Blue 1, 7, 9, 15, 23, 25, 40, 61: 1, 62, 72, 74, 80, 83, 90, 92, 103, 104, 112, 113, 114, 120, 127, 127: 1, 128, 129, 138, 140, 142, 156, 158, 171, 182, 185, 193, 199, 201, 203, 204, 205, 207, 209, 220, 221, 224, 225, 229, 230, 239, 249, 258, 260, 264, 277: 1, 278, 279, 280, 284, 290, 296, 298, 300, 317, 324, 333, 335, 338, 342, 350, and other blue dyes; C. I. Acid Green 9, 12, 16, 19, 20, 25, 27, 28, 40, 43, 56, 73, 81, 84, 104, 108, 109, and other green dyes; C.I. I. Acid Black 1, 2, 3, 24, 24: 1, 26, 31, 50, 52, 52: 1, 58, 60, 63, 107, 109, 112, 119, 132, 140, 155, 172, 187, And black dyes such as 188, 194, 207, and 222.

  Specific examples of the direct dye contained in the aqueous black ink composition of the present invention include C.I. I. Direct Yellow 8, 11, 12, 21, 28, 33, 39, 44, 49, 50, 85, 86, 87, 88, 89, 98, 100, 110, 132, 142, 144, 146, etc. A dye; I. Orange dyes such as Direct Orange 17, 26, 39, 102; I. Direct Red 2, 4, 6, 9, 17, 23, 26, 28, 31, 39, 54, 55, 57, 62, 63, 64, 65, 68, 72, 75, 76, 79, 80, 81, 83 83: 1, 84, 89, 92, 95, 99, 111, 141, 173, 180, 184, 207, 211, 212, 214, 218, 221, 223, 224, 225, 226, 227, 232, 233 Red dyes such as C., 240, 241, 242, 243, 247; I. Violet dyes such as Direct Violet 7, 9, 47, 48, 51, 66, 90, 93, 94, 95, 98, 100, 101; I. Direct Blue 1, 15, 22, 25, 41, 76, 77, 80, 86, 87, 90, 98, 106, 108, 120, 158, 163, 168, 199, 200, 201, 202, 226, etc. Dyes of the system; C. I. Brown dyes such as Direct Brown 106; C.I. I. Direct Black 17, 19, 22, 31, 32, 51, 62, 71, 74, 112, 113, 154, 168, 195 and the like; and the like.

  Among these toning dyes, C.I. I. Direct Yellow 86, 132, 142, C.I. I. Direct Orange 17, 39, C.I. I. Direct Red 80, 227, C.I. I. Direct Brown 106, C.I. I. Direct Acid 95, C.I. I. In the case of containing one or two or more dyes selected from Acid Red 249, 254, the black ink composition of the present invention is further preferable because the range of color reproducibility can be further expanded.

  When other dyes (iii) are contained, (I) 5 to 40% by mass of (i), 20 to 80% by mass of (ii), and 10 to 60% by mass of (iii) in the total mass of the pigment component It is particularly preferable to contain 10 to 30% by mass of (i), 40 to 70% by mass of (ii), and 10 to 40% by mass of (iii).

  The water-based black ink composition of the present invention is prepared using water as a medium. If necessary, the water-soluble organic solvent (organic solvent miscible with water) (component (II)) or the like can be used as long as the effects of the present invention are not impaired. You may contain an ink preparation agent suitably. The pH of the ink composition is preferably pH 6 to 10 and more preferably pH 7 to 10 in terms of improving storage stability. Moreover, as surface tension of a coloring composition, 25-70 mN / m is preferable and 25-60 mN / m is more preferable. Furthermore, the viscosity of the colored composition is preferably 30 mPa · s or less, and more preferably 20 mPa · s or less.

  Examples of the water-soluble organic solvent (component (II)) used in the preparation of the aqueous black ink composition include C1-C4 such as methanol, ethanol, propanol, isopropanol, butanol, isobutanol, secondary butanol, and tertiary butanol. Carboxylic acid amides such as alkanol, N, N-dimethylformamide or N, N-dimethylacetamide, lactams such as 2-pyrrolidone and N-methylpyrrolidin-2-one, 1,3-dimethylimidazolidin-2-one or 1 , Cyclic ureas such as 3-dimethylhexahydropyrimido-2-one, ketones such as acetone, methyl ethyl ketone, 2-methyl-2-hydroxypentan-4-one, or cyclic ethers such as ketoalcohol, tetrahydrofuran, dioxane, Ethylene glycol, 1, -Propylene glycol, 1,3-propylene glycol, 1,2-butylene glycol, 1,4-butylene glycol, 1,6-hexylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, polyethylene glycol, Monomers, oligomers or polyalkylene glycols or thioglycols having (C2-C6) alkylene units such as polypropylene glycol, thiodiglycol and dithiodiglycol, polyols such as glycerin, hexane-1,2,6-triol (triols), Ethylene glycol monomethyl ether or ethylene glycol monoethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether , Polyhydric alcohols (C1 -C4) alkyl ethers such as diethylene glycol monobutyl ether (butyl carbitol) or triethylene glycol monomethyl ether or triethylene glycol monoethyl ether, gamma-butyrolactone or dimethyl sulfoxide and the like. Among these water-soluble organic solvents, 2-pyrrolidone, isopropyl alcohol, glycerin, diglycerin, butyl carbitol, ethylene glycol, diethylene glycol, and propylene glycol are preferable, and 2-pyrrolidone, isopropyl alcohol, glycerin, Butyl carbitol. These organic solvents may be used alone or in combination of two or more.

  The preferable content rate of the water-soluble solvent is 0 to 50% by mass, and more preferably 25 to 50% by mass with respect to the total amount of the aqueous black ink composition of the present invention.

  Examples of the ink preparation used in the preparation of the aqueous black ink composition include antiseptic / antifungal agents, pH adjusters, chelating reagents, rust preventives, water-soluble ultraviolet absorbers, water-soluble polymer compounds, dye solubilizers, and oxidation agents. Examples thereof include an inhibitor and a surfactant.

  Examples of the antifungal agent include sodium dehydroacetate, sodium benzoate, sodium pyridinethione-1-oxide, p-hydroxybenzoic acid ethyl ester, 1,2-benzisothiazolin-3-one and salts thereof. These are preferably used in the coloring composition in an amount of 0.02 to 1.00% by mass.

  Examples of the preservative include organic sulfur, organic nitrogen sulfur, organic halogen, haloallylsulfone, iodopropargyl, N-haloalkylthio, (double) nitrile, pyridine, 8-oxyquinoline, Benzothiazole, isothiazoline, dithiol, pyridine oxyd, nitropropane, organotin, phenol, quaternary ammonium salt, triazine, thiazine, anilide, adamantane, dithiocarbamate, brominated indanone , Benzyl bromacetate compounds, inorganic salt compounds and the like. Examples of the organic halogen compound include sodium pentachlorophenol, examples of the pyridine oxido compound include sodium 2-pyridinethiol-1-oxide, and examples of the inorganic salt compound include anhydrous sodium acetate. Examples of the isothiazoline-based compound include 1,2-benzisothiazolin-3-one, 2-n-octyl-4-isothiazolin-3-one, 5-chloro-2-methyl-4-isothiazolin-3-one, and 5 -Chloro-2-methyl-4-isothiazolin-3-one magnesium chloride, 5-chloro-2-methyl-4-isothiazolin-3-one calcium chloride, 2-methyl-4-isothiazolin-3-one calcium chloride, etc. Can be mentioned. Other antiseptic / antifungal agents include sodium sorbate, sodium benzoate and the like.

  As the pH adjuster, any substance can be used as long as it can control the pH of the ink within a range of, for example, 5 to 11 without adversely affecting the prepared ink. Examples include alkanolamines such as diethanolamine, triethanolamine, N-methyldiethanolamine, alkali metal hydroxides such as lithium hydroxide, sodium hydroxide, potassium hydroxide, ammonium hydroxide (ammonia), or lithium carbonate. And alkali metal carbonates such as sodium carbonate, sodium hydrogen carbonate and potassium carbonate, and inorganic bases such as potassium acetate, sodium silicate and disodium phosphate.

  Examples of the chelating reagent include sodium ethylenediaminetetraacetate, sodium nitrilotriacetate, sodium hydroxyethylethylenediaminetriacetate, sodium diethylenetriaminepentaacetate, sodium uracil diacetate and the like.

  Examples of the rust inhibitor include acidic sulfite, sodium thiosulfate, ammonium thioglycolate, diisopropylammonium nitrite, pentaerythritol tetranitrate, and dicyclohexylammonium nitrite.

  Examples of the water-soluble ultraviolet absorber include sulfonated benzophenone compounds, benzotriazole compounds, salicylic acid compounds, cinnamic acid compounds, and triazine compounds.

  Examples of the water-soluble polymer compound include polyvinyl alcohol, cellulose derivatives, polyamines and polyimines.

  Examples of the dye solubilizer include ε-caprolactam, ethylene carbonate, urea and the like. In particular, when urea (component (III)) is contained, it is one of the preferred embodiments of the present invention.

  As the antioxidant, for example, various organic and metal complex antifading agents can be used. Examples of the organic anti-fading agent include hydroquinones, alkoxyphenols, dialkoxyphenols, phenols, anilines, amines, indanes, chromans, alkoxyanilines, heterocycles, and the like.

Examples of the surfactant include known surfactants such as anionic, cationic, and nonionic surfactants. Examples of anionic surfactants include alkyl sulfonates, alkyl carboxylates, α-olefin sulfonates, polyoxyethylene alkyl ether acetates, N-acyl amino acids and their salts, N-acyl methyl taurates, alkyl sulfate polys. Oxyalkyl ether sulfate, alkyl sulfate polyoxyethylene alkyl ether phosphate, rosin acid soap, castor oil sulfate ester, lauryl alcohol sulfate ester, alkylphenol type phosphate ester, alkyl type phosphate ester, alkyl allyl sulfone hydrochloride, diethyl sulfo Examples thereof include oxalate, diethylhexylsilsulfosuccinate, dioctylsulfosuccinate and the like. Examples of the cationic surfactant include 2-vinylpyridine derivatives and poly-4-vinylpyridine derivatives. Amphoteric surfactants include lauryldimethylaminoacetic acid betaine, 2-alkyl-N-carboxymethyl-N-hydroxyethylimidazolinium betaine, coconut oil fatty acid amidopropyldimethylaminoacetic acid betaine, polyoctylpolyaminoethylglycine and other imidazoline derivatives. is there. Nonionic surfactants include polyoxyethylene nonyl phenyl ether, polyoxyethylene octyl phenyl ether, polyoxyethylene dodecyl phenyl ether, polyoxyethylene oleyl ether, polyoxyethylene lauryl ether, polyoxyethylene alkyl ether, polyoxyallylalkyl. Ethers such as alkyl ethers, polyoxyethylene oleic acid, polyoxyethylene oleate, polyoxyethylene distearate, sorbitan laurate, sorbitan monostearate, sorbitan monooleate, sorbitan sesquioleate, polyoxyethylene monooleate Esters, polyoxyethylene stearate, 2,4,7,9-tetramethyl-5-decyne-4,7-di Lumpur, 3,6-dimethyl-4-octyne-3,6-diol, 3,5-dimethyl-1-hexyne-3 acetylene glycol such as ol (e.g., manufactured by Nissin Chemical Industry Co., Ltd. Surfynol ^RTM 104 and 105 , 82, 420, 440, 465, Olfine ^RTM STG, etc.). Of these, Surfynol ^RTM 420, 440 and 465 are preferably used, and Surfynol ^RTM 440 is particularly preferably used. In the present specification, the superscript “RTM” means a registered trademark.

  These ink preparation agents are used alone or in combination.

  In the production of the aqueous black ink composition of the present invention, there is no particular limitation on the order of dissolving each agent such as an additive. The water used for the preparation of the black ink composition is preferably water with few impurities such as ion exchange water and distilled water. Further, if necessary, after the ink composition is prepared, fine filtration may be performed using a membrane filter or the like to remove impurities in the ink composition. In particular, when the ink composition of the present invention is used as an ink for ink jet recording, it is preferable to perform microfiltration. The pore size of the filter used for microfiltration is usually 1 to 0.1 μm, preferably 0.8 to 0.1 μm.

  The water-based black ink composition of the present invention can be used in various fields, and is suitable for a water-based ink for writing, a water-based printing ink, an information recording ink, and the like, and an ink-jet ink containing the ink composition. It is particularly preferably used as the ink jet recording method of the present invention, which will be described later.

  Next, the ink jet recording method of the present invention will be described. The inkjet recording method of the present invention is characterized in that recording is performed using the aqueous black ink composition of the present invention as an inkjet ink. In the ink jet recording method of the present invention, recording is performed on the image receiving material using the aqueous black ink composition of the present invention, but there are no particular restrictions on the ink nozzles used at that time, and they are appropriately selected according to the purpose. Known methods, for example, a charge control method that ejects ink using electrostatic attraction, a drop-on-demand method (pressure pulse method) that uses the vibration pressure of a piezo element, and an electrical signal to an acoustic beam. Use an acoustic ink jet system that irradiates the changed ink and ejects the ink using the radiation pressure, a thermal ink jet (bubble jet (registered trademark)) system that uses the pressure generated by heating the ink to form bubbles. be able to. The inkjet recording method includes a method of ejecting a large number of low-density inks called photo inks in a small volume, a method of improving image quality using a plurality of inks having substantially the same hue and different concentrations, and colorless and transparent. A method using ink is included.

  The colored body of the present invention is colored with the aqueous black ink composition of the present invention, and more preferably is colored with an ink jet printer using the aqueous black ink composition of the present invention. Examples of materials that can be colored include information transmission sheets such as paper and film, fibers and cloth (cellulose, nylon, wool, etc.), leather, and base materials for color filters. The information transmission sheet is preferably a surface-treated sheet, specifically, a sheet such as paper, synthetic paper, or film provided with an ink receiving layer. For the ink-receiving layer, for example, a porous white inorganic substance capable of absorbing the pigment in the ink such as porous silica, alumina sol, and special ceramics by impregnating or coating the above-mentioned base material with a cationic polymer is used. It is provided by coating the surface of the substrate together with a hydrophilic polymer such as polyvinylpyrrolidone. A paper provided with such an ink receiving layer is usually called ink jet dedicated paper (film), glossy paper (film), etc., for example, as a typical commercial product, Pictorico (manufactured by Asahi Glass Co., Ltd.), professional photo paper, Super photo paper, matte photo paper, glossy gold, platinum grade (all manufactured by Canon Inc.), photo paper (gloss), photo matte paper, photo paper Crispia (high gloss) (all manufactured by Seiko Epson Corp.) , Premium Plus Photo Paper, Premium Glossy Film, Photo Paper, Advanced Photo Paper (all manufactured by Hewlett-Packard Japan), Photo-like QP (manufactured by Konica Corporation), Painting Photo Finishing Pro (Fuji Film Co., Ltd.) ))). Of course, plain paper, high-quality paper, and coated paper can also be used.

  Among these, it is known that an image recorded on a recording material coated with a porous white inorganic material on the surface is greatly discolored by ozone gas, but the aqueous black ink composition of the present invention is resistant to ozone gas. Therefore, it is also effective when recording on such a recording material.

  In order to record on the recording material by the ink jet recording method of the present invention, for example, a container containing the above ink composition may be set at a predetermined position of the ink jet printer and recorded on the recording material by a normal method. . In the ink jet recording method of the present invention, a black ink composition of the present invention, a publicly known magenta ink composition, a cyan ink composition, a yellow ink composition, and a green ink composition, blue (or violet) as necessary. Used in combination with an ink composition and a red (or orange) ink composition. The ink composition of each color is poured into each container, and the container is used by being loaded into a predetermined position of the ink jet printer in the same manner as the container containing the aqueous black ink composition for ink jet recording of the present invention. Examples of the ink jet printer include a piezo printer using mechanical vibration and a bubble jet (registered trademark) printer using bubbles generated by heating.

The water-based black ink composition of the present invention is very clear on a recording material such as plain paper and an information transmission sheet having an ink receiving layer, has a high saturation and printing density, and has a black recorded image with an ideal hue. give. Therefore, it is also possible to faithfully reproduce a photographic color image on paper. In addition, the aqueous black ink composition of the present invention has very good storage stability without solid precipitation, physical property change, hue change and the like after long-term storage.
The aqueous black ink composition of the present invention is used for inkjet recording and writing instruments, and even when used as an inkjet ink, solid precipitation due to drying of the ink composition near the nozzle is very unlikely to occur. ) Is not blocked. In addition, the aqueous black ink composition of the present invention uses a continuous ink jet printer, and when the ink is recirculated at a relatively long time interval or used intermittently by an on-demand ink jet printer, Does not cause changes in physical properties.
Furthermore, the image recorded on the information transmission sheet having the ink receiving layer by the aqueous black ink composition of the present invention has various fastness properties such as water resistance, moisture resistance, ozone gas resistance, abrasion resistance, and light resistance. In particular, water resistance and ozone gas resistance are good, and for this reason, the long-term storage stability of photographic images is also excellent. Compared to conventional inks, it also has excellent color development properties such as saturation, brightness, and print density on plain paper, color rendering properties, especially sensor compatibility in the near-infrared light region, and high color development properties. Yes.
Thus, the water-based black ink composition of the present invention is extremely useful for various recording ink applications, particularly ink jet recording ink applications.

EXAMPLES The present invention will be described more specifically with reference to examples. However, the present invention is not limited to the examples. Unless otherwise specified, “part” and “%” in the text are based on mass, and the reaction temperature is the internal temperature. Moreover, in each structural formula of the compound obtained in the Example, acidic functional groups, such as a carboxy group and a sulfo group, were described in the form of a free acid. Examples 1 to 3 are synthesis examples of the compound represented by the formula (2).
[(A) Synthesis of black dye]
[Example 1]
(Process 1)
After reacting 20.1 parts of 2-amino-5-naphthol-1,7-disulfonic acid and 12.6 parts of p-toluenesulfonyl chloride at pH 8.0 to 8.5 at 70 ° C. for 1 hour, it was acidified. Then, 28.4 parts of the compound of the formula (17) obtained by salting out and filtering are dissolved in 300 parts of water while adjusting the pH to 6.0 to 8.0 with sodium carbonate, and 35% hydrochloric acid 18. After the addition of 7 parts, the temperature was changed to 0 to 5 ° C., and 10.7 parts of 40% aqueous sodium nitrite solution was added to diazotize.

  After adding a solution obtained by suspending 19.1 parts of 4-amino-5-hydroxynaphthalene-1,7-disulfonic acid in 200 parts of water to the diazo suspension, the pH value of the solution was adjusted to 10 to 20 ° C. The mixture was stirred for 12 hours while being maintained at 2.4 to 2.8 with sodium. Subsequently, it melt | dissolved as 7.0-8.5 with sodium carbonate, and the solution containing the monoazo compound of Formula (18) was obtained.

(Process 2)
14.4 parts of sodium 4-nitroaniline-2-sulfonate are dissolved in 150 parts of water, and 18.8 parts of 35% hydrochloric acid and 10.6 parts of 40% aqueous sodium nitrite solution are added thereto at 0 to 5 ° C. Diazotized. While maintaining this diazo suspension in a solution containing the monoazo compound of the formula (18) obtained by the above reaction at 10 to 20 ° C. and maintaining the pH value of the solution at 8.0 to 9.0 with sodium carbonate, It was dripped. After completion of dropping, the mixture is stirred at 15 to 30 ° C. for 2 hours at pH 8.0 to 9.0, salted out by adding sodium chloride, and filtered to obtain a wet cake containing the compound of formula (19). It was.

  The wet cake obtained above was dissolved in 400 parts of water, heated to 70 ° C., and stirred for 1 hour while maintaining the pH value at 10.5 to 11.0 with sodium hydroxide. After cooling to room temperature, the pH was adjusted to 7.0 to 8.0 with 35% hydrochloric acid, sodium chloride was added for salting out, and filtration was performed to obtain a wet cake containing the compound of formula (20).

(Process 3)
17.0 parts of the compound of the formula (21) are dissolved in 170 parts of water by adding lithium hydroxide to a pH of 7.0 to 8.0, and 17.4 parts of 35% hydrochloric acid, 40% Diazotization was performed by adding 8.7 parts of an aqueous sodium nitrate solution.

  This diazo suspension was dissolved in a solution obtained by dissolving a wet cake containing the compound of formula (20) in 400 parts of water at 10 to 25 ° C., and the pH value of the solution was 8.0 to 9.0 with lithium hydroxide. The solution was added dropwise while being held. After completion of the dropwise addition, the mixture was stirred at 15 to 30 ° C. for 2 hours at pH 8.0 to 9.0, salted out by addition of lithium chloride, and collected by filtration. The obtained wet cake was dissolved in 400 parts of water, and crystallized and filtered by addition of 1000 parts of 2-propanol. Further, the obtained wet cake was dissolved in 300 parts of water, and then crystallized by adding 900 parts of 2-propanol, filtered, and dried to obtain an azo compound of the formula (22) (No. 1 compound in Table 2). 49.0 parts were obtained as the lithium salt. The maximum absorption wavelength (λmax) of this compound in an aqueous solution of pH 9 was 590 nm, and the solubility in water at room temperature was 100 g / L or more.

[Example 2]
In the same manner as in Example, except that 14.4 parts of sodium 4-nitroaniline-2-sulfonate in Step 2 of Example 1 was changed to 14.4 parts of sodium 2-nitroaniline-4-sulfonate, the formula 47.0 parts of the azo compound (No. 3 compound in Table 2) of (23) was obtained as a lithium salt. The maximum absorption wavelength (λmax) of this compound in an aqueous solution at pH 9 was 592 nm, and the solubility in water at room temperature was 100 g / L or more.

[Example 3]
(Process 1)
Dissolve 11.5 parts of sodium 4-nitroaniline-2-sulfonate in 100 parts of water and add 14.1 parts of 35% hydrochloric acid and 8.6 parts of 40% aqueous sodium nitrite solution at 0-5 ° C. Diazotized. To this diazo suspension was added 100 parts of water, and 12.3 parts of the compound of the formula (24) obtained by the method described in Example 2 of Patent Document 4 was added with sodium hydroxide to a pH of 5.0 to 6.0. The solution dissolved as was added dropwise while maintaining at 10 to 15 ° C. After completion of the dropwise addition, the pH was adjusted to 6.0 to 7.0 over 1 hour by adding sodium carbonate, and the mixture was stirred at 15 to 20 ° C. for 2 hours and at pH 6.0 to 7.0. Sodium chloride was added for salting out, and filtration was performed to obtain a wet cake containing the compound of formula (25).

(Process 2)
In the same manner as in Example 1, except that a wet cake containing the compound of the formula (25) obtained by the above reaction was used instead of 17.0 parts of the compound of the formula (21) in (3) of Example 1, the formula 50.1 parts of the azo compound (No. 16 compound in Table 4) of (26) was obtained as a lithium salt. The maximum absorption wavelength (λmax) of this compound in an aqueous solution at pH 9 was 615 nm, and the solubility in water at room temperature was 100 g / L or more.

[(B) Preparation of Black Ink Composition]
[Examples 4 to 6]
The black ink composition of the present invention was mixed with the components shown in Table 5 below and stirred for about 1 hour until the solid content was dissolved. Then, a 0.45 μm membrane filter (trade name, cellulose acetate filter paper) The black ink composition for a test was prepared by filtering with Advantech). The dyes were prepared in combinations described in Examples 4 to 6 below.

[Example 4]
C. I. Acid Green 1 (X = 1.5 parts)
Compound of Example (1) (X = 3.5 parts)
Total X = 5.0 parts

[Example 5]
C. I. Acid Green 1 (X = 1.5 parts)
Compound of Example (1) (X = 3.0 parts)
C. I. Direct Orange 39 (X = 0.5 part)
Total X = 5.0 parts

[Example 6]
C. I. Acid Green 1 (X = 1.5 parts)
Compound of Example (1) (X = 2.5 parts)
C. I. Direct Red 80 (X = 0.5 part)
C. I. Direct Orange 39 (X = 0.5 part)
Total X = 5.0 parts

  These aqueous black ink compositions did not cause precipitation separation during storage and did not change their physical properties even after long-term storage.

  As Comparative Examples 1 and 2, as in Examples 4 to 7, dyes for comparative examples were mixed at the composition ratios shown in Table 5, and black ink compositions for comparative examples were prepared in the same manner.

[Comparative Example 1]
Compound of Example (1) (X = 3.0)
C. I. Direct Red 80 (X = 1.0)
C. I. Direct Orange 39 (X = 1.0)
Total X = 5.0

[Comparative Example 2]
C. I. Direct Black 19 (X = 5.0 parts)
Total X = 5.0 parts

[(C) Inkjet print]
Using the respective ink compositions obtained in Examples 4 to 6 and Comparative Examples 1 and 2, inkjet recording was performed on high-quality plain paper (Mitsubishi Paper Corporation DL9084) using an inkjet printer (trade name: Canon IP4100). It was.
At the time of printing, an image pattern was prepared so that gradations with several levels of reflection density were obtained, and a half-tone black print was obtained. Since the gray scale mode is used at the time of printing, yellow, cyan and magenta recording liquids other than the black recording liquid are not used together. Among the test methods described below, in the print density evaluation, which is an item to be evaluated using a colorimeter, when measuring the print density (reflection density D value) of a printed material, the portion with the highest D value is used. It was. Similarly, when the reflectance in the near-infrared region was evaluated using a spectrophotometer, the measurement was performed using the gradation portion having the highest D value of the printed matter.

[(D) Evaluation of recorded image]
For the recorded image by the water-based ink composition of the present invention, two points of printing density (DB value) and reflectance (%) were evaluated. The results are shown in Table 6. The test method is shown below.
1) Evaluation of Print Density (DB Value) The print density (DB value) of the recorded image was measured using GRETAG / SPM50 (manufactured by GRETAG) to calculate the print density DB value. The criteria are shown below.

○: DB> 1.60
Δ: 1.60 ≧ DB> 1.30
×: DB ≦ 1.30

2) Reflectance Evaluation The reflectance of the recorded image was measured using an ultraviolet-visible near-infrared spectrophotometer UV3150 (manufactured by Shimadzu Corporation), and the reflectance% in the near-infrared light region was calculated. The reflectance 1 is a reflectance measured at 700 nm, and the reflectance 2 is a reflectance measured at 800 nm. The criteria are shown below.

○: Reflectance ≦ 20%
Δ: 20% <reflectance ≦ 50%
×: Reflectance> 50%

  From Table 6, the aqueous black ink composition of the present invention has a high printing density, a lower reflectance in the near-infrared light region than that of the conventional black ink (comparative example), and excellent absorption of near-infrared light. You can see that

The aqueous black ink composition of the present invention is excellent in printing density and sensor compatibility characteristics. Therefore, it is suitably used as a black ink liquid for ink jet recording and writing instruments.

Claims (15)

(I) A water-based black ink composition comprising, as a dye component, (i) a water-soluble compound represented by the following formula (1) or a salt thereof.

The aqueous black ink composition according to claim 1, further comprising (I) a dye component having (ii) a dye having three or more azo bonds (-N = N-) in the molecule. The aqueous black ink composition according to claim 2, wherein the dye having three or more azo bonds (-N = N-) in the molecule is a black dye represented by the following formula (2) or a salt thereof.

(In the formula (2), R ¹ , R ² , R ⁵ , R ⁶ and R ⁷ are each independently a hydrogen atom, halogen atom, cyano group, hydroxy group, carboxy group, sulfo group, sulfamoyl group, N-alkyl. Aminosulfonyl group, N-phenylaminosulfonyl group, (C1-C4) alkylsulfonyl group, phospho group, nitro group, acyl group, ureido group, (C1-C4) alkyl group (hydroxy group) which may be substituted with hydroxy group Or (C1-C4) which may be substituted with an alkoxy group), (C1-C4) alkoxy group (which may be substituted with a hydroxyl group, a (C1-C4) alkoxy group, a sulfo group or a carboxy group), An acylamino group, an alkylsulfonylamino group or a phenylsulfonylamino group (even if it is substituted with a halogen atom, an alkyl group or a nitro group) R ³ and R ⁴ are each independently a hydrogen atom, halogen atom, cyano group, carboxy group, sulfo group, nitro group, (C1-C4) alkyl group (hydroxy group or (C1-C4) alkoxy group) Or (C1-C4) alkoxy group (which may be substituted with a hydroxy group, (C1-C4) alkoxy group, sulfo group or carboxy group), an acylamino group, an alkylsulfonylamino group, or A phenylsulfonylamino group (which may be substituted with a halogen atom, an alkyl group or a nitro group), n represents 0 or 1, respectively) 4. The aqueous black ink composition according to claim 3, wherein in formula (2), R ¹ is a carboxy group or a sulfo group, R ² is a hydrogen atom, R ⁶ is a carboxy group or a sulfo group, and n is 1. 5. When R ¹ is a sulfo group and the substitution position of R ¹ is ortho to the azo group, the substitution position of the nitro group is para to the azo group, and the substitution position of R ¹ is para to the azo group In this case, the water-based black ink composition according to claim 3 or 4, wherein the substitution position of the nitro group is ortho to the azo group. The aqueous black ink composition according to any one of claims 3 to 5, wherein R ³ is a sulfo group, R ⁴ is a hydrogen atom, R ⁵ is a hydrogen atom, a carboxy group or a sulfo group, and R ⁷ is a hydrogen atom. The aqueous black ink composition according to claim 3, wherein the black dye represented by the previous formula (2) is a black dye represented by the following formula (3) or a salt thereof.

(In the formula (3), when R ¹ is a sulfo group and the substitution position of R ¹ is ortho to the azo group, the substitution position of the nitro group is para to the azo group, and the substitution position of R ¹ is (In the case of para position to the azo group, the substitution position of the nitro group is ortho position to the azo group.) Furthermore, (iii) C.I. I. Direct Yellow 86, 132, 142, C.I. I. Direct Orange 17, 39, C.I. I. Direct Red 80, 227, C.I. I. Direct Brown 106, C.I. I. Acid Orange 95, C.I. I. The aqueous black ink composition according to any one of claims 2 to 7, comprising one or two or more dyes selected from Acid Red 249, 254. (I) The aqueous black according to claim 8, comprising 5 to 40% by mass of (i), 20 to 80% by mass of (ii), and 10 to 60% by mass of (iii) in the total mass of the pigment component. Ink composition. The aqueous black ink composition according to any one of claims 1 to 9, further comprising (II) a water-soluble organic solvent. The aqueous black ink composition according to any one of claims 1 to 10, further comprising (III) urea. An ink jet recording method using the water-based black ink composition according to any one of claims 1 to 11. The inkjet recording method according to claim 12, wherein the recording material in the inkjet recording method is an information transmission sheet. An ink jet printer loaded with a container containing the aqueous black ink composition according to claim 1. A colored body colored with the water-based black ink composition according to any one of claims 1 to 11.