JP2012193310A - Red ink, ink cartridge, inkjet recording method, and inkjet recording apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a red ink capable of obtaining an image excellent in color developability, light resistance and gas resistance.
A red ink comprising a color material having a specific structure and a yellow color material having an azo structure.
[Selection figure] None

Description

  The present invention relates to a red ink, an ink cartridge, an inkjet recording method, and an inkjet recording apparatus that are also suitable for inkjet.

  One of the means for improving the image quality in the ink jet recording method is to use so-called special color inks such as red, green and blue in addition to inks of basic colors of cyan, magenta, yellow and black (Patent Document 1). reference). In recent years, as in the case of basic color inks, such special color inks are required to improve the color developability of images obtained more than ever, and the image storage stability such as gas resistance and light resistance. One technique for achieving these is to improve the color developability and fastness of the dye contained in the ink, and there is a proposal for a dye having such characteristics. For example, regarding magenta color materials, it has been disclosed that fastness can be improved by specific anthrapyridone color materials, and that fastness can be improved for xanthene color materials having the property of excellent color development. (See Patent Documents 1 and 2).

JP 2006-176605 A JP 2005-008868 A JP-A-9-241553

  In recent years, it has been required to achieve a higher level of performance than ever for images obtained by the ink jet recording method. Therefore, the present inventors have examined the conventional techniques as mentioned above. However, most of the conventional techniques are for basic color inks, and for special color inks that are important for improving image quality, especially red inks, the color development properties, light resistance, It was found that gas resistance could not be achieved. For example, even when the magenta color material described in Patent Document 2 is applied to the red ink described in Patent Document 1, the color developability and light resistance of the obtained image are insufficient. In addition, even if the color material described in Patent Document 3 is applied, the hue becomes bluish, so it cannot be used as a red ink, and in addition, the light resistance and gas resistance of the obtained image are insufficient. It is.

  Accordingly, an object of the present invention is to provide a red ink from which an image excellent in color development, light resistance and gas resistance can be obtained. Another object of the present invention is to provide an ink cartridge, an ink jet recording method, and an ink jet recording apparatus using the red ink.

  The above object is achieved by the present invention described below. That is, the red ink of the present invention is characterized by containing a color material represented by the following general formula (1) and a yellow color material having an azo structure.

(In general formula (1), R ₁ , R ₅ , R ₆ and R ₁₀ each independently represents an alkyl group. R ₃ and R ₈ each independently represent a hydrogen atom, an alkyl group, an alkoxy group, or aryl. R ₂ , R ₄ , R ₇ and R ₉ each independently represents a hydrogen atom or an acylamino group represented by the following general formula (2), and R ₂ , R ₄ , R ₇ and R ₉ Is an acylamino group represented by the following general formula (2): Z represents an SO ₃ H group, SO ₃ M group or sulfamoyl group, M represents an ammonium ion or an alkali metal ion, and Z represents The aromatic ring is substituted at the position of at least one hydrogen atom, and when at least one of R ₂ , R ₃ , R ₄ , R ₇ , R ₈ and R ₉ is substituted with an ionic group, n is An integer from 0 to 3 When n is not substituted with an ionic group, n represents an integer of 1 to 3.)

(In the general formula (2), R ₁₁ represents an alkyl group, a cycloalkyl group, an aryl group, an arylalkyl group, an alkenyl group, or a heterocyclic group. * Represents a bond to an aromatic ring in the general formula (1). Represents the site.)

  ADVANTAGE OF THE INVENTION According to this invention, the red ink from which the image excellent in coloring property, light resistance, and gas resistance is obtained can be provided. In addition, according to another embodiment of the present invention, an ink cartridge, an ink jet recording method, and an ink jet recording apparatus using the red ink can be provided.

The graph which shows the result of ¹ H NMR analysis of a coloring material (8). The graph which shows the result of ¹ H NMR analysis of a coloring material (11). The graph which shows the result of ¹ H NMR analysis of a coloring material (14). The graph which shows the result of ¹ H NMR analysis of a coloring material (15). The graph which shows the result of UV / Vis spectroscopic analysis of various coloring materials.

  Hereinafter, the present invention will be described in more detail with reference to preferred embodiments.

  The inventors of the present invention have studied the configuration of red ink that can provide an image excellent in color developability, light resistance, and gas resistance. Specifically, C.I. I. A color material having a magenta color developing property equivalent to Acid Red 289 and capable of improving light resistance and gas resistance was examined. In particular, C.I. I. The structure of the coloring material that can improve the low light resistance and gas resistance, which are the weak points of Acid Red 289, was examined. As a result, a colorant represented by the general formula (1) described later was found. Furthermore, by using the color material represented by the general formula (1) and the yellow color material having an azo structure as the color material of the red ink, an image excellent in color developability, light resistance and gas resistance can be obtained. As a result, the present invention has been obtained.

  The reason why the above effect is obtained by using the red ink having such a configuration is presumed as follows. The xanthene skeleton in the general formula (1) exhibits high color developability, and the electron withdrawing group is present in the structure of the general formula (1), so that it is difficult to lose electrons from the colorant molecule. Deterioration of coloring material due to gas is difficult to occur, and light resistance and gas resistance are excellent. Furthermore, due to the structure having excellent symmetry, the color material represented by the general formula (1) is regularly laminated when applied to the recording medium, so that it interacts with the yellow color material having an azo structure. In addition, it is considered that the yellow color material is also protected. For these reasons, it is considered that the red ink of the present invention can provide an image excellent in color developability, light resistance and gas resistance.

<Red ink>
The red ink of the present invention contains a color material represented by the following general formula (1) and a yellow color material having an azo structure, and can be used particularly suitably for inkjet. The red ink in the present invention has a hue angle (H °) measured for an ink or an image recorded with the ink of 5 ° to 75 ° C., further 10 ° to 70 °, particularly 15 °. The ink is in the range of not less than 65 ° and not more than 65 °. It should be noted that the hue angle can be measured with a general spectrophotometer, and the measurement target can be an aqueous solution in which ink is diluted 2,000 times (mass basis).

  Hereinafter, components to be contained in the red ink of the present invention will be described. In the following description, red ink is ink, color material represented by general formula (1) is color material of general formula (1), and color material having an azo structure is yellow color material. May be described.

(Coloring material represented by general formula (1))
The ink of the present invention contains a color material (dye) represented by the following general formula (1).

(In general formula (1), R ₁ , R ₅ , R ₆ and R ₁₀ each independently represents an alkyl group. R ₃ and R ₈ each independently represent a hydrogen atom, an alkyl group, an alkoxy group, or aryl. R ₂ , R ₄ , R ₇ and R ₉ each independently represents a hydrogen atom or an acylamino group represented by the following general formula (2), and R ₂ , R ₄ , R ₇ and R ₉ Is an acylamino group represented by the following general formula (2): Z represents an SO ₃ H group, SO ₃ M group or sulfamoyl group, M represents an ammonium ion or an alkali metal ion, and Z represents The aromatic ring is substituted at the position of at least one hydrogen atom, and when at least one of R ₂ , R ₃ , R ₄ , R ₇ , R ₈ and R ₉ is substituted with an ionic group, n is An integer from 0 to 3 When n is not substituted with an ionic group, n represents an integer of 1 to 3.)

(In the general formula (2), R ₁₁ represents an alkyl group, a cycloalkyl group, an aryl group, an arylalkyl group, an alkenyl group, or a heterocyclic group. * Represents a bond to an aromatic ring in the general formula (1). Represents the site.)

In general formula (1), R ₁ , R ₅ , R ₆ and R ₁₀ each independently represents an alkyl group. Examples of the alkyl group include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, hydroxyethyl group, methoxyethyl group, cyanoethyl group, Examples thereof include a trifluoromethyl group. Among these, alkyl groups having 1 to 3 carbon atoms such as methyl group, ethyl group, and propyl group are particularly preferable from the viewpoint of synthesis. The alkyl group may have a substituent, and as the substituent, for example, a hydroxy group, an alkoxy group, a cyano group, a halogen atom and the like are preferable from the viewpoint of synthesis. When R ₁ , R ₅ , R ₆ and R ₁₀ have a substituent, it is preferable that the substituents are all the same in terms of spectral reflection characteristics such as color developability, hue and transparency, hue, and synthesis. .

In general formula (1), R ₃ and R ₈ each independently represent a hydrogen atom, an alkyl group, an alkoxy group, or an aryloxy group. Examples of the alkyl group include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, hydroxyethyl group, methoxyethyl group, cyanoethyl group, A trifluoromethyl group, a 3-sulfopropyl group, a 4-sulfobutyl group and the like can be mentioned. Examples of the alkoxy group include a methoxy group, an ethoxy group, an isopropoxy group, a methoxyethoxy group, a hydroxyethoxy group, and a 3-carboxypropoxy group. Examples of the aryloxy group include a phenoxy group, a p-methoxyphenoxy group, an o-methoxyphenoxy group, a tolyloxy group, a xylyloxy group, and a naphthoxy group. The alkyl group, alkoxy group, and aryloxy group may have a substituent. Examples of the substituent include an alkyl group, aryl group, arylalkyl group, hydroxy group, carbamoyl group, sulfamoyl group, alkoxy group, cyano group, halogen atom, and ionic group. Examples of the ionic group include a cationic group such as a triethylammonium group and a trimethylammonium group, and an anionic group such as a carboxy group, a sulfonic acid group, and a phosphoric acid group. In the present invention, R ₃ and R ₈ are preferably a methyl group, an ethyl group, or a propyl group from the viewpoint of light resistance. In addition, in terms of synthesis, when R ₃ and R ₈ have a substituent, it is preferable that all the substituents are the same.

In general formula (1), R ₂ , R ₄ , R ₇ and R ₉ each independently represent a hydrogen atom or an acylamino group represented by general formula (2), and R ₂ , R ₄ , R ₇ and At least one of R ₉ is an acylamino group represented by the general formula (2). C. I. Similarly to Acid Red 289, in order to have high light resistance and gas resistance while the colorant of the general formula (1) has high color developability, R ₂ , R ₄ , R ₇ , R ₉ It is necessary that at least one is an acylamino group represented by the general formula (2). In the present invention, the number of acylamino groups of the general formula (2) is preferably 2 to 4 in terms of color developability and light resistance. Moreover, when the coloring material of General formula (1) has two or more acylamino groups of General formula (2), it is preferable that each acylamino group is the same at the point on a synthesis | combination. Furthermore, in terms of synthesis, combinations of R ₁ and R ₆ , R ₂ and R ₇ , R ₃ and R ₈ , R ₄ and R ₉ , R ₅ and R ₁₀ in the general formula (1) are the same. Preferably there is.

In General Formula (2), R ₁₁ represents an alkyl group, a cycloalkyl group, an aryl group, an arylalkyl group, an alkenyl group, or a heterocyclic group. Examples of the alkyl group include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, hydroxyethyl group, methoxyethyl group, cyanoethyl group, A trifluoromethyl group, a 3-sulfopropyl group, a 4-sulfobutyl group and the like can be mentioned. Examples of the cycloalkyl group include a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and the like. Examples of the aryl group include a phenyl group, a p-tolyl group, a p-methoxyphenyl group, an o-chlorophenyl group, and an m- (3-sulfopropylamino) phenyl group. Examples of the arylalkyl group include a benzyl group and a 2-phenethyl group. Examples of the alkenyl group include a vinyl group, a 1-propenyl group, a 2-propenyl group, a 1-methylethenyl group, a 1-butenyl group, a 2-butenyl group, and a 3-butenyl group. Examples of the heterocyclic group include imidazolyl, benzoimidazolyl, pyrazolyl, benzopyrazolyl, triazolyl, thiazolyl, benzothiazolyl, isothiazolyl, benzoisothiazolyl, oxazolyl, benzoxazolyl, and thiadiazolyl groups. , Pyrrolyl group, benzopyrrolyl group, indolyl group, isoxazolyl group, benzoisoxazolyl group, thienyl group, benzothienyl group, furyl group, benzofuryl group, pyridyl group, quinolyl group, isoquinolyl group, pyridazinyl group, pyrimidinyl group, pyrazinyl group Cinnolinyl group, phthalazinyl group, quinazolinyl group, quinoxalinyl group, triazinyl group and the like.

Each group of R ₁₁ may have a substituent. Examples of the substituent include an alkyl group, an aryl group, an arylalkyl group, an alkenyl group, an alkoxy group, a cyano group, an alkylamino group, a sulfoalkyl group, a carbamoyl group, a sulfamoyl group, a sulfonylamino group, a halogen atom, and an ionic group. Etc. Examples of the ionic group include a cationic group such as a triethylammonium group and a trimethylammonium group, and an anionic group such as a carboxy group, a sulfonic acid group, and a phosphoric acid group. In the present invention, R ₁₁ is preferably an alkyl group, a cycloalkyl group, an aryl group, or an arylalkyl group from the viewpoint of color development, and particularly preferably an alkyl group or an aryl group from the viewpoint of synthesis. preferable. Among them, in terms of particularly excellent light resistance is obtained, R ₁₁ is an alkyl group of straight-chain, it is preferred ionic group is an aryl group substituted.

In general formula (1), Z represents a SO ₃ H group, a SO ₃ M group or a sulfamoyl group, M represents an ammonium ion or an alkali metal ion, and Z is substituted at the position of at least one hydrogen atom of the aromatic ring. is doing. Examples of the sulfamoyl group include an aminosulfonyl group, a methylaminosulfonyl group, a dimethylaminosulfonyl group, and a butylaminosulfonyl group. M in the SO ₃ M group is a counter ion, for example, an alkali metal such as lithium, sodium or potassium, unsubstituted ammonium, methylammonium, dimethylammonium, trimethylammonium, tetramethylammonium, ethylammonium, diethylammonium, triethylammonium , Tetraethylammonium, n-propylammonium, isopropylammonium, diisopropylammonium, n-butylammonium, tetran-butylammonium, isobutylammonium, monoethanolammonium, diethanolammonium, triethanolammonium and the like. Especially, it is preferable that M is a lithium ion, a sodium ion, and an ammonium ion at the point that the solubility with respect to water is favorable. In the present invention, Z is preferably an SO ₃ M group because the colorant of the general formula (1) is excellent in solubility in an aqueous medium. In addition, since at least a part of the SO ₃ M group in the ink causes ion dissociation to become counter ions, it is described as “counter ion” in the present invention, but there may be cases where ion dissociation has not occurred. Of course, it is included in the present invention.

In the general formula (1), when at least one of R ₂ , R ₃ , R ₄ , R ₇ , R ₈ and R ₉ is substituted with an ionic group, n represents an integer of 0 to 3, When not substituted with a sex group, n represents an integer of 1 to 3. From the viewpoint of good solubility in water, n is preferably 1 to 2.

The substitution position of Z in the general formula (1) is determined by the substitution position of other substituents in the general formula (1) and the conditions for sulfonation or chlorosulfonation. When any of R ₂ , R ₃ , R ₄ , R ₇ , R _8, and R ₉ is a hydrogen atom, the hydrogen atom is replaced by any hydrogen atom or a hydrogen atom of a xanthene skeleton. When R ₁₁ has an aromatic ring and an aromatic hydrogen atom exists, the hydrogen atom may be substituted. When any of R ₂ , R ₃ , R ₄ , R ₇ , R ₈ and R ₉ is not a hydrogen atom and no aromatic hydrogen atom is present in the substituent of R ₁₁ , only a hydrogen atom in the xanthene skeleton Replace.

Hereinafter, typical examples of the case where R ₂ and R ₇ in the general formula (1) are acylamino groups represented by the general formula (2) (structures represented by the following general formula (1 ′)) are given as examples. The position of disulfonation is shown. Of course, the present invention is not limited to these.

[Synthesis Method of Color Material Represented by General Formula (1)]
The color material of the general formula (1) can be synthesized based on a known production method. An example of a synthesis scheme is shown below. _R 1 _{to R} 10, Z, n in (1) and (4) to (7) in the synthetic schemes, the same meanings as _R 1 _{to R} 10, Z, n in the general formula (1).

In the synthesis scheme illustrated in 0 above, the general formula is obtained through the first condensation step shown in the first step, the second condensation step shown in the second step, the sulfonation or sulfamoylation step shown in the third step. The color material (1) is synthesized. However, when an ionic group such as a sulfonic acid group or a carboxy group is present as a substituent of R ₂ , R ₃ , R ₄ , R ₇ , R ₈ and R ₉ , sulfonation or sulfamoylation shown in the third stage The process may not be performed.

  First, in the first condensation step, compound (3) and compound (4) are heated and condensed in the presence of an organic solvent or a condensing agent to obtain compound (5). Next, in the second condensation step, compound (6) and compound (5) obtained in the first condensation step are heated and condensed to obtain compound (7). Finally, in the third condensation step, the compound (7) obtained in the second condensation step is sulfonated using a sulfonating agent, whereby Z of the general formula (1) in which Z is a sulfonic acid group. A color material is obtained. Moreover, the coloring material of General formula (1) whose Z is a sulfamoyl group is obtained by sulfamoylating a compound (7) by the method mentioned later.

  The organic solvent used in the condensation step of the synthesis scheme exemplified above will be described. In the first condensation step, for example, methanol, ethanol, n-propanol, isopropanol, n-butanol and the like are preferably used alone or in combination. In the second condensation step, for example, ethylene glycol, N-methylpyrrolidone, N, N-dimethylacetamide, N, N-dimethylformamide, dimethyl sulfoxide, sulfolane, chlorobenzene, dichlorobenzene, trichlorobenzene, nitrobenzene and the like alone or It is preferable to use a mixture.

  The reaction temperature in the first condensation step is preferably 60 ° C. to 100 ° C., more preferably 70 ° C. or higher, and more preferably 90 ° C. or lower. The reaction temperature in the second condensation step is preferably 120 ° C. to 220 ° C., and more preferably 180 ° C. or less.

When synthesizing a coloring material in which R _{1 to} R ₅ and R _{6 to} R ₁₀ in the general formula (1) are the same group, the compounds (4) and (6) in the above scheme are the same. Can be used. Therefore, in this case, compound (7) can be obtained by performing a one-step condensation process from compound (3). The reaction temperature at that time is preferably 120 ° C. to 220 ° C., more preferably 180 ° C. or less. As the condensing agent, for example, magnesium oxide, zinc chloride, aluminum chloride or the like is preferably used.

  As the sulfonating agent used in the sulfonation step of the synthetic scheme exemplified above, for example, as described in “New Experimental Chemistry Course Vol. 14”, Maruzen Publishing Co., Ltd., 1978, pp. 1776-1784, Any known sulfonating agent can be used. Specific examples include sulfuric acid, fuming sulfuric acid, sulfur trioxide, chlorosulfonic acid, fluorosulfonic acid, and amidosulfuric acid. In the present invention, from the viewpoint of reactivity and ease of handling of the sulfonating agent. It is preferable to use fuming sulfuric acid. Moreover, as a sulfamoylation process of the synthetic scheme illustrated above, as long as a desired compound is obtained by sulfamoylation, it may be performed by any method. For example, a method of chlorosulfonating the compound (7) using chlorosulfonic acid or the like and sulfamoylating with a corresponding amine can be mentioned. Further, there may be mentioned a method in which sulfonation is carried out in advance by the above-mentioned sulfonation step, followed by halogenation with thionyl halide and the like, and then sulfamoylation with a corresponding amine. Examples of amines used in these sulfamoylation steps include concentrated aqueous ammonia, alkylamines, and arylamines. In the present invention, it is preferable to employ a process through chlorosulfonation in terms of the number of synthesis steps.

  Although the sulfonation step and the sulfamoylation step can be performed without using a solvent, it is preferably performed in the presence of a solvent in order to suppress rapid progress of the reaction. Any solvent can be used as long as it does not inhibit the reaction. Specifically, for example, acids such as sulfuric acid, acetic acid and acetic anhydride, aliphatic halides such as chloroform, dichloromethane, dichloroethane and carbon tetrachloride, chlorobenzene, o-dichlorobenzene, m-dichlorobenzene, p-dichlorobenzene, Aromatic halides such as bromobenzene, nitrobenzene, dinitrobenzene, 2-nitrotoluene, 3-nitrotoluene, 4-nitrotoluene, 2-chloronitrobenzene, 4-fluoronitrobenzene and other aromatic nitro compounds, methylsulfone, ethylsulfone, phenylsulfone , Sulfolane, sulfones such as 2,4-dimethylsulfolane, and the like, and one or more solvents can be used.

  The reaction temperature in the sulfonation step or sulfamoylation step is usually preferably -20 ° C to 150 ° C, more preferably -5 ° C to 50 ° C, particularly preferably 0 ° C to 40 ° C. The reaction of the sulfonation step or sulfamoylation step is usually completed within 24 hours.

  The coloring compound (dye), which is the final product obtained by the above synthesis scheme, can be used as an ink coloring material by performing purification in accordance with a post-treatment method of a normal organic synthesis reaction, followed by purification.

[Exemplified Compound of Coloring Material Represented by General Formula (1)]
Preferred examples of the color material represented by the general formula (1) include the color materials (8) to (26) shown in Table 2 below. Of course, the present invention is not limited to the following coloring materials as long as they are included in the structure of the general formula (1) and the definition thereof. In the present invention, among the following coloring materials, it is particularly preferable to use the coloring materials (8), (11), (14) and (15). In Table 2, “Me” represents a methyl group, “Et” represents an ethyl group, “n-Pr” represents a normal propyl group, “i-Pr” represents an isopropyl group, and “*” represents a substituent binding site. .

(Other magenta color materials)
In the present invention, a magenta color material other than the color material represented by the general formula (1) may be contained in the ink as long as the effects of the present invention are not impaired. Specific examples of suitable magenta color materials (dyes) that can be used with the color material represented by the general formula (1) in the present invention will be given below, but the present invention is not limited to these magenta color materials.

  First, C.I. I. Examples of the magenta color material having a number include the following. C. I. Direct Red: 2, 4, 9, 11, 20, 23, 24, 31, 39, 46, 62, 75, 79, 80, 83, 89, 95, 197, 201, 218, 220, 224, 225, 226 227, 228, 229, 230, etc. C. I. Acid Red: 6, 8, 9, 13, 14, 18, 26, 27, 32, 35, 42, 51, 52, 80, 83, 87, 89, 92, 106, 114, 115, 133, 134, 145 158, 198, 249, 265, 289, etc. C. I. Food Red: 87, 92, 94, etc.

  Further, magenta color materials described in JP-A-8-73791, JP-A-2006-143898, WO 2004/104108 pamphlet, JP-A-2003-192930 and the like can be mentioned. Specifically, a color material having the following structure in the form of a free acid is preferable.

(Yellow color material with azo structure)
The ink of the present invention contains a yellow color material (dye) having an azo structure. Examples of the yellow color material that can be suitably used in the present invention include the following. For example, the hue angle (H °) measured for an image recorded with an aqueous solution of a yellow color material or an ink containing only a yellow color material as a color material is in a range of 65 ° to 125 °. Materials. The hue angle is preferably 70 ° to 120 °, and particularly preferably 75 ° to 110 °. The hue angle can be measured with a general spectrophotometer, and the content of the coloring material in the aqueous solution to be measured can be about 0.002%. The yellow color material contained in the ink of the present invention preferably has good color developability, and has a maximum absorption wavelength in water of 370 to 490 nm, further 380 to 475 nm, particularly 390 to 460 nm. Those are preferred.

  The following are specific examples of yellow color materials having an azo structure that can be contained in the ink of the present invention. Of course, since it is important to use a yellow color material having an azo structure in the present invention, the yellow color material is not limited to the following as long as this requirement is satisfied. In the present invention, the color material having an azo structure preferably has a disazo structure. A color material having such a structure is particularly preferred because it can improve the color developability, gas resistance and light resistance of the resulting image in a well-balanced manner. In the present invention, it is particularly preferable that the coloring material having an azo structure has a dimeric disazo structure in which two monoazo units having the same structure are bonded via a linking group. A color material having such a structure is particularly preferred because it can improve the color developability, gas resistance and light resistance of the resulting image in a well-balanced manner.

・ C. I. Direct yellow: 8, 12, 27, 33, 44, 50, 85, 86, 88, 89, 98, 100, 110, 132, 173, etc. I. Acid Yellow: 11, 17, 23, 25, 29, 36, 38, 40, 42, 44, 76, 98, etc.

  -Color material represented by the general formula (27) (described in JP-T-2002-504613)

(In General Formula (30), R ₁ and R ₂ each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted arylalkyl group. R ₃ and R ₅ each independently represent a carboxy group, a sulfonic acid group, a phosphoric acid group, or a salt thereof, or an alkyl group substituted with any of these groups, and R ₄ and R ₆ are each independently , R ₃ and R ₅ represent groups other than those defined above, p and r are each independently an integer of 1 to 5, q and s are each independently an integer of 0 to 4, and p + q ≦ 5 and r + s ≦ 5.)

In the present invention, R ₄ and R ₆ in the general formula (27) are preferably each independently a hydrogen atom, a halogen atom, or a substituted or unsubstituted alkyl group. When R ₃ and R ₅ are salts, examples of cations that form salts include alkali metal ions such as lithium, potassium, and sodium, ammonium ions, and organic ammonium ions.

  When a preferred specific example of the color material represented by the general formula (27) is shown in the form of a free acid, the following yellow color material 1 can be mentioned.

  -Colorant represented by the general formula (28) (described in JP-A-2003-321627)

(In General Formula (28), R ₁ and R ₂ each independently represents a hydrogen atom, an alkyl group, an alkoxy group, an alkanoylamino group, an alkoxyalkoxy group, a sulfonic acid group, a carboxy group, or a ureido group. n is each independently 1 or 2. M independently represents a hydrogen atom, an alkali metal, an ammonium ion, or an organic ammonium ion.)
When a preferred specific example of the color material represented by the general formula (28) is shown as a free acid form, the following yellow color material 2 can be mentioned.

  -Color material represented by the general formula (29) (described in JP 09-2117018 A)

(In General Formula (29), R ₁ and R ₂ are each independently a hydrogen atom, a ureido group, an alkyl group having 1 to 3 carbon atoms, an alkoxy group having 1 to 3 carbon atoms, or 1 to 3 carbon atoms. Represents an acylamino group of _3. R ₃ represents a hydrogen atom or an aliphatic group having 1 to 6 carbon atoms, x is 1 to 3, and the substitution position of the sulfonic acid group is when x is 1. Is 1st, 4th, 5th, 6th, 7th, or 8th, and when x is 2 or 3, 4th and 8th; 5th and 7th; 6th and 8th; 1 And 3rd, 6th and 8th positions; and 4th, 6th and 8th positions, and y and z are each independently 2 to 6.)

  When a preferred specific example of the color material represented by the general formula (29) is shown as a free acid form, the following yellow color material 3 can be mentioned.

  -Color material represented by the general formula (30) (described in the pamphlet of International Publication No. 2008/053776)

(In General Formula (30), R represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, or a sulfonic acid group. N is an integer of 1 or 2, and m is 1. An integer of 1 to 3, x is an integer of 2 to 4, and y is an integer of 1 to 3. M independently represents a hydrogen atom, an alkali metal, ammonium, or organic ammonium.)

  When a preferred specific example of the color material represented by the general formula (30) is shown as a free acid form, the following yellow color material 4 can be mentioned.

  -Color material represented by the following general formula (31)

(In General Formula (31), D represents a linking group. Ar ₁ , Ar _2, and Ar ₃ each independently represent an atomic group having a 5-membered or 6-membered unsaturated cyclic structure, and constitute a cyclic structure. The carbon atom may be substituted with at least one of a nitrogen atom and a sulfur atom, and R ₃₁ , R ₃₂ , R ₃₃ and R ₃₄ are each independently a hydrogen atom, an alkyl group, an aryl group, an alkyloxy group, or a halogeno group. , Acyl group, carbamoyl group, alkyloxycarbonyl group, aryloxycarbonyl group, cyano group, nitro group, amino group, alkylamino group, dialkylphosphono group, diarylphosphono group, diarylphosphinyl group, alkylsulfinyl group, Arylsulfinyl group, alkylsulfonyl group, arylsulfonyl group, sulfonyloxy group, acylthio group, Rufamoiru group, a thiocyanate group, a thiocarbonyl group, a halogenated alkoxy group, a halogenated aryloxy group, a halogenated alkylamino group, a halogenated alkylthio group, or each .R ₃₅ and R ₃₆ independently represents an acyloxy group, a hydrogen atom represents a carboxy group, a sulfonic acid group, a phosphoric acid group, an alkyl group, or an aryl group, an alkyl group and aryl group, a carboxy group, a sulfonic acid group, or phosphoric acid group may be substituted, R ₃₅ and The ionic group of R ₃₆ may form a salt.)

  A color material represented by the following general formula (32) (described in the pamphlet of International Publication No. 2006/082669). This color material is a more preferable specific example of the color material represented by the general formula (31).

(In General Formula (32), R ₁ , R ₂ , Y ₁ , and Y ₂ are each independently a monovalent group, and X ₁ and X ₂ are each independently having a Hammett's σp value of 0.20 or more. Z ₁ and Z ₂ are each independently a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, substituted or unsubstituted The aralkyl group, the substituted or unsubstituted aryl group, or the substituted or unsubstituted heterocyclic group, and M represents a hydrogen atom, an alkali metal, ammonium, or organic ammonium.)

  Specific examples of the electron withdrawing group having a Hammett σp value of 0.20 or more include an acyl group, an acyloxy group, a carbamoyl group, an alkyloxycarbonyl group, an aryloxycarbonyl group, a cyano group, a nitro group, Dialkylphosphono group, diarylphosphono group, diarylphosphinyl group, alkylsulfinyl group, arylsulfinyl group, alkylsulfonyl group, arylsulfonyl group, sulfonyloxy group, acylthio group, sulfamoyl group, thiocyanate group, thiocarbonyl group, halogen Alkyl group, halogenated alkoxy group, halogenated aryloxy group, halogenated alkylamino group, halogenated alkylthio group, aryl group substituted with other electron-withdrawing group having σp value of 0.20 or more, heterocycle Group, halogen atom, azo group, or Examples include selenocyanate groups.

  When a preferred specific example of the color material represented by the general formula (32) is shown as a form of a free acid, the following yellow color material 5 can be mentioned. As the yellow color material used in the present invention, the following yellow color material 5 is particularly suitable.

(Coloring material content)
In the present invention, the content (% by mass) of the coloring material of the general formula (1) in the ink is 0.1% by mass or more and 10.0% by mass or less, and further 0.1% based on the total mass of the ink. It is preferable that they are mass% or more and 5.0 mass% or less. The content (% by mass) of the yellow color material having an azo structure in the ink is 0.1% by mass or more and 10.0% by mass or less, further 0.1% by mass or more and 5% by mass or more based on the total mass of the ink. It is preferable that it is 0.0 mass% or less.

  In the present invention, the total content (% by mass) of the color materials in the ink is preferably 10.0% by mass or less based on the total mass of the ink. Furthermore, the total content is preferably 1.0% by mass or more and 10.0% by mass or less, and particularly preferably 1.5% by mass or more and 7.0% by mass or less. When the total content is less than 1.0% by mass, the color developability, light resistance and gas resistance of the image may not be obtained at a sufficiently high level, and when the total content exceeds 10.0% by mass. In some cases, ink jet properties such as fixing recovery properties cannot be obtained sufficiently.

  Further, in the ink of the present invention, the color material of the general formula (1) and the yellow color material having an azo structure contained in the ink preferably have a mass ratio of their respective contents in a specific range. This is because an ink having a hue angle preferable as a red ink can be obtained, and furthermore, an image particularly excellent in color development, light resistance and gas resistance can be obtained. For this reason, the content of the color material of the general formula (1) in the ink is 0.20 times or more and 3.00 times or less in terms of mass ratio with respect to the content of the yellow color material having an azo structure. Is preferably 0.40 times or more and 2.50 times or less. The content in this case is a value based on the total mass of the ink.

(Aqueous medium)
In the ink of the present invention, an aqueous medium that is a mixed solvent of water and a water-soluble organic solvent can be used. It is preferable to use deionized water (ion exchange water) as the water. The content (% by mass) of water in the ink is preferably 10.0% by mass or more and 90.0% by mass or less based on the total mass of the ink. The content (% by mass) of the water-soluble organic solvent in the ink is 3.0% by mass or more and 50.0% by mass or less, more preferably 15.0% by mass or more and 40.0% by mass based on the total mass of the ink. % Or less is preferable. If the content of the water-soluble organic solvent is less than 3.0% by mass, ink jet characteristics such as ink ejection stability may not be sufficiently obtained. If the content exceeds 50.0% by mass, the ink In some cases, the ink is not sufficiently smoothly supplied to the recording head.

  The water-soluble organic solvent is not particularly limited as long as it can be generally used for ink-jet ink, and any conventionally known one can be used, and one kind or two or more kinds can be used. A combination of water-soluble organic solvents can be contained in the ink. Specifically, monohydric or polyhydric alcohols, alkylene glycols having an alkylene group of about 1 to 4 carbon atoms, polyethylene glycols having an average molecular weight of about 200 to 2,000, glycol ethers, nitrogen-containing compounds Etc. can be used.

(Other additives)
In addition to the above-described components, the ink of the present invention may be used at room temperature such as polyhydric alcohols such as trimethylolpropane and trimethylolethane, urea derivatives such as urea and ethyleneurea, saccharides and derivatives thereof. A solid water-soluble organic compound may be contained. Furthermore, for each ink constituting the ink set of the present invention, a surfactant, a pH adjuster, a rust inhibitor, an antiseptic, an antifungal agent, an antioxidant, an antioxidant, an evaporation accelerator, Various additives such as a chelating agent and a resin may be contained. In the present invention, it is preferable to use an acetylene glycol-based surfactant. Among them, an ethylene oxide adduct of acetylene glycol is particularly preferable because of its excellent solubility in an aqueous medium.

(Ink physical properties)
The static surface tension at 25 ° C. of the ink of the present invention is preferably 10 mN / m to 60 mN / m, more preferably 20 mN / m to 60 mN / m, and particularly preferably 30 mN / m to 40 mN / m. Each ink constituting the ink set of the present invention has a surface tension within the above-described range, so that when it is applied to an ink jet system, the ejection deviation due to wetting in the vicinity of the ejection opening (displacement of ink landing point), etc. Generation | occurrence | production can be suppressed effectively. Adjustment of the surface tension of the ink can be performed by appropriately determining the content of a surfactant or the like in the ink. Further, the ink of the present invention is preferably adjusted to a desired pH so as to obtain good ejection characteristics when applied to an ink jet recording apparatus. The viscosity at 25 ° C. of each ink constituting the ink set of the present invention is preferably 1.0 mPa · s or more and 5.0 mPa · s or less.

<Ink cartridge>
The ink cartridge of the present invention includes an ink storage portion that stores ink, and the ink storage portion stores the ink of the present invention described above. As for the structure of the ink cartridge, the ink storage portion includes an ink storage chamber that stores liquid ink and a negative pressure generation member storage chamber that stores a negative pressure generation member that holds the ink therein by a negative pressure. Things. Alternatively, the ink cartridge may be an ink container that does not have an ink storage chamber for storing liquid ink and is configured to hold the entire storage capacity by a negative pressure generating member. Further, the ink cartridge may be configured to have an ink storage portion and a recording head.

<Inkjet recording method and inkjet recording apparatus>
The ink jet recording method of the present invention includes an image recording step of recording an image on a recording medium by ejecting the ink of the present invention described above by an ink jet recording head. In the image recording process, the ink of the present invention described above is used. The ink jet recording apparatus of the present invention is an apparatus that includes an ink storage unit that stores ink, and a recording head that discharges ink. And the ink accommodated in the said ink accommodating part is the ink of this invention demonstrated above, It is characterized by the above-mentioned. Other than using the ink of the present invention, the steps and configuration of the ink jet recording method and the recording apparatus may be known ones.

  As a recording medium for recording an image using the ink of the present invention, any recording medium that can be used for general inkjet can be used. Examples of such a recording medium include an inkjet recording medium having a porous layer on a support such as glossy paper, coated paper, and glossy film, or so-called copy paper in which fibers are exposed on at least a part of the surface. Ordinary paper such as

  Further, the ink of the present invention may be used in the ink jet recording method in combination with another ink. Examples of such inks include black, cyan, magenta, yellow, blue, and green inks (dark inks) that contain a dye as a coloring material. Moreover, each ink (light ink), such as light cyan, light magenta, light yellow, and gray, which contains a dye as a coloring material.

  EXAMPLES Hereinafter, although this invention is demonstrated further in detail using an Example, a reference example, and a comparative example, this invention is not limited at all by the following Example, unless the summary is exceeded. Unless otherwise specified, “%” is based on mass.

<Preparation of coloring material>
(Identification of colorant of general formula (1))
Identification of the color material of the general formula (1) synthesized below was performed using the following apparatuses.
[1] ¹ H NMR analysis: ¹ H nuclear magnetic resonance spectroscopy (ECA-400; manufactured by JEOL Ltd.)
[2] LC / MS analysis: LC / TOF MS (LC / MSD TOF; manufactured by Agilent Technologies). In addition, as an ionization method in LC / TOF MS, an electrospray ionization method (ESI) was adopted.
[3] UV / Vis spectroscopic analysis: UV / Vis spectrophotometer (UV-36000 spectrophotometer; manufactured by Shimadzu Corporation).

(Synthesis of coloring material (8))
A color material (8) having the following structure was synthesized by the following procedure.

  3-acetylamino-2,4,6-trimethylaniline (7.3 g) and compound (3) (7.4 g) in the above synthesis scheme were combined with zinc chloride (4.1 g) in sulfolane (20 mL). In the presence, the reaction was carried out by heating at 150 ° C. for 3 hours. After cooling this solution, it was added to 50 mL of 2N hydrochloric acid, and the precipitated crystals were separated by filtration, washed with water, and dried. 6 g of this dried product was added to 30 g of fuming sulfuric acid under ice cooling, and then stirred at 20 to 25 ° C. for 4 hours. The reaction solution was discharged onto 100 g of ice, and the precipitated sulfonated product was filtered off and washed with cold water to obtain a precipitate. The obtained precipitate was suspended in 50 mL of water, dissolved in 2N aqueous sodium hydroxide solution to pH 7.0, and then crystallized with acetone to obtain a coloring material (8).

It was confirmed by ¹ H NMR analysis, LC / TOF MS analysis, and UV / Vis spectroscopic analysis that the obtained coloring material (8) had the above structure. The analysis results are shown below.
[1] Results of ¹ H NMR analysis (400 MHz, DMSO-d ₆ , room temperature) (see FIG. 1):
δ [ppm] = 11.26 (s, 2H), 9.35 (d, 2H), 7.92 (d, 1H), 7.57 (t, 1H), 7.49 (t, 1H), 7.16 (d, 1H), 7.11 (d, 2H), 7.01 (m, 2H), 6.29 (dd, 2H), 3.38 (s, 18H), 2.09 (s) , 6H)
[2] Results of LC / TOF MS analysis (eluent: 0.1% aqueous acetic acid-methanol, ESI):
Retention time 5.0 min: Purity = 23.6 area%, m / z = 795.21 (n = 1, [M-Na] ⁻ )
Retention time 6.4 minutes: Purity = 75.0 area%, m / z = 897.15 (n = 2, [M-Na] ⁻ ), 875.16 (n = 2, [M-2Na ⁺ H] ⁻ )
[3] Results of UV / Vis spectroscopic analysis (see FIG. 5):
λ _max = 527 nm, ε = 95594 M ⁻¹ cm ⁻¹ (solvent: H ₂ O, 25 ° C.).

(Synthesis of coloring material (11))
A color material (11) having the following structure was synthesized by the following procedure.

  3-isobutyrylamino-2,4,6-trimethylaniline (8.4 g) and compound (3) (7.4 g) in the above synthesis scheme were combined with zinc chloride (4.1 g) in sulfolane (20 mL). In the presence of), the reaction was carried out by heating at 150 ° C. for 3 hours. After cooling this solution, it was added to 50 mL of 2N hydrochloric acid, and the precipitated crystals were separated by filtration, washed with water, and dried. 6 g of this dried product was added to 30 g of fuming sulfuric acid under ice cooling, and then stirred at 20 to 25 ° C. for 4 hours. The reaction solution was discharged onto 100 g of ice, and the precipitated sulfonated product was filtered off and washed with cold water to obtain a precipitate. The obtained precipitate was suspended in 50 mL of water, dissolved in 2N aqueous sodium hydroxide solution to pH 7.0, and then crystallized with acetone to obtain a coloring material (11).

It was confirmed by ¹ H NMR analysis, LC / TOF MS analysis, and UV / Vis spectroscopic analysis that the obtained coloring material (11) had the above structure. The analysis results are shown below.
[1] Results of ¹ H NMR analysis (400 MHz, DMSO-d ₆ , room temperature) (see FIG. 2):
δ [ppm] = 11.27 (s, 2H), 9.35 (s, 1H), 9.25 (s, 1H), 8.02 (d, 1H), 7.70 (t, 1H), 7.61 (t, 1H), 7.56 (s, 2H), 7.31 (m, 1H), 7.13 (m, 2H), 5.98 (s, 2H), 2.64 (m) 2H), 2.15 (m, 6H), 2.09 (m, 12H), 1.13 (m, 12H)
[2] Results of LC / TOF MS analysis (eluent: 0.1% aqueous acetic acid-methanol, ESI):
Retention time 10.2 min: Purity = 97.0 area%, m / z = 931.1 (n = 2, [M-2Na ⁺ H] ⁻ )
[3] Results of UV / Vis spectroscopic analysis (see FIG. 5):
λ _max = 530 nm, ε = 78967 M ⁻¹ cm ⁻¹ (solvent: H ₂ O, 25 ° C.).

(Synthesis of coloring material (14))
A color material (14) having the following structure was synthesized by the following procedure.

  3,5-Diacetylamino-2,4,6-trimethylaniline (6.7 g) and compound (3) (7.4 g) in the above synthesis scheme were combined with zinc chloride (4.1 g) in sulfolane (20 mL). In the presence of), the reaction was carried out by heating at 150 ° C. for 3 hours. After cooling this solution, it was added to 50 mL of 2N hydrochloric acid, and the precipitated crystals were separated by filtration, washed with water, and dried. 5 g of this dried product was added to 30 g of concentrated sulfuric acid under ice cooling, and then stirred at 25 to 30 ° C. for 4 hours. The reaction solution was discharged onto 100 g of ice, and the precipitated sulfonated product was filtered off and washed with cold water to obtain a precipitate. The obtained precipitate was suspended in 50 mL of water, dissolved in 6N aqueous sodium hydroxide solution to pH 7.0, and then crystallized with acetone to obtain a coloring material (14).

It was confirmed by ¹ H NMR analysis, LC / TOF MS analysis, and UV / Vis spectroscopic analysis that the obtained coloring material (14) had the above structure. The analysis results are shown below.
[1] Results of ¹ H NMR analysis (400 MHz, DMSO-d ₆ , room temperature) (see FIG. 3):
δ [ppm] = 10.19 (brs, 2H), 9.49 (m, 4H), 8.02 (d, 1H), 7.67 (t, 1H), 7.59 (t, 1H), 7.55 (m, 1H), 7.29 (d, 2H), 7.16 (m, 1H), 5.92 (s, 1H), 5.80 (s, 1H), 3.38 (s) , 18H), 2.05 (m, 12H)
[2] Results of LC / TOF MS analysis (eluent: 0.1% aqueous acetic acid-methanol, ESI):
Retention time 3.8 minutes: Purity = 86.0 area%, m / z = 909.26 (n = 1, [M-Na] ⁻ )
Retention time 6.4 min: Purity = 8.4 area%, m / z = 1011.19 (n = 2, [M−H] ⁻ )
[3] Results of UV / Vis spectroscopic analysis (see FIG. 5):
λ _max = 528 nm, ε = 85888 M ⁻¹ cm ⁻¹ (solvent: H ₂ O, 25 ° C.).

(Synthesis of coloring material (15))
A color material (15) having the following structure was synthesized by the following procedure.

  15.0 g of the coloring material (8) obtained above was refluxed in concentrated hydrochloric acid for 30 hours, cooled, and then discharged into 200 mL of cold water. The discharged liquid was adjusted to pH 7.0 with a 25% aqueous sodium hydroxide solution at 20 to 30 ° C., and then stirred for 30 minutes. Thereafter, the crystals were filtered off, washed with water, and then dried to obtain a deacetylated product of the coloring material (8). The deacetylated product (2.5 g) of the obtained color material (8) and phthalic anhydride (1.4 g) were reacted in 20 mL of N, N-dimethylformamide at 50 to 60 ° C. for 6 hours. . After cooling the reaction solution, it was added to 50 mL of 2N hydrochloric acid, and the precipitated crystals were separated by filtration. The obtained crystals were washed with water, dissolved in a 2N aqueous sodium hydroxide solution, and then crystallized with ethanol to obtain a coloring material (15).

It was confirmed by ¹ H NMR analysis, LC / TOF MS analysis, and UV / Vis spectroscopic analysis that the obtained coloring material (15) had the above structure. The analysis results are shown below.
[1] Results of ¹ H NMR analysis (400 MHz, DMSO-d ₆ , room temperature) (see FIG. 4):
δ [ppm] = 12.37 (brm, 2H), 10.04 (brs, 2H), 8.00 (dd, 2H), 7.84 (brm, 2H), 7.62 (brm, 4H), 7.39 (brd, 4H), 7.23 (d, 2H), 7.11 (brm, 4H), 5.96 (s, 2H), 2.22 (brs, 6H), 2.11 (brs) , 6H), 2.00 (brs, 6H)
[2] Results of LC / TOF MS analysis (eluent: 0.1% aqueous acetic acid-methanol, ESI):
Retention time 19.4 min: Purity = 99.1 area%, m / z = 949.24 ([M-Na] ⁻ ), 927.26 ([M-2Na ⁺ H] ⁻ )
[3] Results of UV / Vis spectroscopic analysis (see FIG. 5):
λ _max = 530 nm, ε = 111574 M ⁻¹ cm ⁻¹ (solvent: H ₂ O, 25 ° C.).

<Preparation of ink>
Each component (unit:%) shown in the upper part of Tables 3 to 5 is mixed and sufficiently stirred to dissolve, and then subjected to pressure filtration with a microfilter (manufactured by Fuji Film) having a pore size of 0.2 μm. Was prepared. In Tables 3 to 5, the coloring material shown in parentheses is the type of counter ion. In the lower part of Tables 3 to 5, the content A (%) of the color material of the general formula (1) in the ink, the content B (%) of the yellow color material having an azo structure, and the value of A / B ( Times). Further, acetylenol E100 used for the preparation of the following inks is a nonionic surfactant manufactured by Kawaken Fine Chemicals.

<Preparation of recorded material>
Each ink obtained above was filled in an ink cartridge and mounted on an ink jet recording apparatus (PIXUSiP8600; manufactured by Canon Inc.). Two types of recording media, glossy paper (Canon Photo Paper / Glossy Pro [Platinum Grade]; manufactured by Canon) and plain paper (PB PAPER GF-500; manufactured by Canon) under conditions of a temperature of 23 ° C. and a relative humidity of 55%. A solid image having a recording duty of 100% was recorded. The above recording apparatus has a resolution of 600 dpi × 600 dpi, and applies and records 8 ink droplets with a discharge amount of 2.5 pL per droplet in a unit area of 1/600 inch × 1/600 inch. The image recording duty is defined as 100%. Further, for inks having a total color material content exceeding 10.0%, an image was obtained by applying the ink to each of the above recording media using an RDS bar coater # 8 (manufactured by RD Specialties). The obtained recorded matter was allowed to stand in an environment having a temperature of 23 ° C. and a relative humidity of 55% for 24 hours to sufficiently dry the image. The following images were evaluated using a reflection densitometer (Spectrolino; manufactured by GretagMacbeth) using L ^* , a ^* , and b ^* in the L ^* a ^* b ^* color system defined by the CIE (International Commission on Illumination). The measurement was performed under the conditions of a light source: D50 and a visual field: 2 °.

<Evaluation>
The following items were evaluated. In the present invention, according to the evaluation criteria in the following evaluation items, C is an unacceptable level and B or more is an acceptable level. The evaluation results are shown in Table 6.

(Hue angle)
From the values of L ^* , a ^* and b ^* measured for the recorded matter obtained using glossy paper, the hue angle (H °) was determined based on the following formulas, and the hue angle was evaluated.

When a ^* ≧ 0 and b ^* ≧ 0 (first quadrant), H ° = tan ⁻¹ (b ^* / a ^* )
When a ^* ≦ 0 and b ^* ≧ 0 (second quadrant), H ° = 180 + tan ⁻¹ (b ^* / a ^* )
For a ^* ≦ 0 and b ^* ≦ 0 (third quadrant), H ° = 180 + tan ⁻¹ (b ^* / a ^* )
For a ^* ≧ 0 and b ^* ≦ 0 (fourth quadrant), H ° = 360 + tan ⁻¹ (b ^* / a ^* ).

The evaluation criteria for the hue angle are as follows.
A: H ° was 15 ° or more and less than 65 ° B: H ° was 10 ° or more and less than 15 °, or H ° was 65 ° or more and 70 ° or less C: H ° was 10 ° Or H ° was greater than 70 °.

(Color development on glossy paper)
From the values of L ^* , a ^* , and b ^* measured for the recorded matter obtained using glossy paper, the saturation (C ^* ) based on the formula C ^* = (a ^{* 2} + b ^{* 2} ) ^1/2 Were evaluated, and the color developability of glossy paper was evaluated. The evaluation criteria of color developability on glossy paper are as follows.
AA: C ^* was 115 or more A: C ^* was 110 or more and less than 115 B: C ^* was 100 or more and less than 110 C: C ^* was less than 100.

(Color development on plain paper)
From the values of L ^* , a ^* , and b ^* measured for the printed matter obtained using plain paper, saturation (C ^* ) based on the formula of C ^* = (a ^{* 2} + b ^{* 2} ) ^1/2 Were evaluated for color development on plain paper. The evaluation criteria for color developability on plain paper are as follows.
AA: C ^* was 75 or more A: C ^* was 72 or more and less than 75 B: C ^* was 68 or more and less than 72 C: C ^* was less than 68.

(Light resistance)
The recorded matter obtained using glossy paper is put into a super xenon tester (SX-75; manufactured by Suga Test Instruments), and the xenon light is converted into an image for 48 hours at a temperature of 24 ° C., a relative humidity of 60%, and an illuminance of 100 klx. Irradiated. Then, the optical density after exposure was measured (referred to as “optical density after test”). And from the change (ΔL ^* , Δa ^* , Δb ^* ) of L ^* , a ^* , b ^* before and after the exposure test, ΔE = ((ΔL ^* ) ² + (Δa ^* ) ² + (Δb ^* ) ² ) ^The color change (ΔE) was obtained based on the expression of ^1/2 , and the light resistance was evaluated. The evaluation criteria for light resistance are as follows.
AA: ΔE was less than 5 A: ΔE was 5 or more and less than 10 B: ΔE was 10 or more and less than 20 C: ΔE was 20 or more.

(Gas resistance)
The recorded matter obtained using glossy paper is put into an ozone test device (OMS-H: manufactured by Suga Test Instruments), and the image is exposed to ozone for 24 hours at a temperature of 23 ° C., a relative humidity of 50% and an ozone concentration of 10 ppm. did. And from the change (ΔL ^* , Δa ^* , Δb ^* ) of L ^* , a ^* , b ^* before and after the exposure test, ΔE = ((ΔL ^* ) ² + (Δa ^* ) ² + (Δb ^* ) ² ) ^The color change (ΔE) was determined based on the expression of ^1/2 , and the gas resistance was evaluated. The evaluation criteria for gas resistance are as follows.
AA: ΔE was less than 5 A: ΔE was 5 or more and less than 10 B: ΔE was 10 or more and less than 20 C: ΔE was 20 or more.

(Adhesive recovery)
Each ink obtained above was filled in an ink cartridge and mounted on an ink jet recording apparatus (PIXUSiP8600; manufactured by Canon Inc.). Then, by performing a suction recovery operation (“print head cleaning” in the recording apparatus), the ink was introduced to the ejection port of the recording head, and then the recording head was taken out from the recording apparatus. This recording head was stored for 14 days in a constant temperature bath at a temperature of 30 ° C. and a relative humidity of 10%. Thereafter, the recording head was mounted on the recording apparatus again. The number of suction recovery operations required until ejection became possible and the state of ink ejection from each ejection port at the time when three suction recovery operations were performed were confirmed, and the fixation recovery property was evaluated. . The evaluation criteria for fixing recovery are as follows. In addition, evaluation of the fixing recovery property about the ink in which the total content of the coloring material exceeds 10.0% was not performed.
A: In 3 times or less of suction, all the discharge ports are restored to a state where they can be discharged without any problem.
B: After performing the suction three times, ejection failure occurs with a few nozzles, but this is an allowable range.
C: After performing suction 3 times, ejection failure occurred at many nozzles.

Claims (7)

A red ink comprising a color material represented by the following general formula (1) and a yellow color material having an azo structure.

(In general formula (1), R ₁ , R ₅ , R ₆ and R ₁₀ each independently represents an alkyl group. R ₃ and R ₈ each independently represent a hydrogen atom, an alkyl group, an alkoxy group, or aryl. R ₂ , R ₄ , R ₇ and R ₉ each independently represents a hydrogen atom or an acylamino group represented by the following general formula (2), and R ₂ , R ₄ , R ₇ and R ₉ Is an acylamino group represented by the following general formula (2): Z represents an SO ₃ H group, SO ₃ M group or sulfamoyl group, M represents an ammonium ion or an alkali metal ion, and Z represents The aromatic ring is substituted at the position of at least one hydrogen atom, and when at least one of R ₂ , R ₃ , R ₄ , R ₇ , R ₈ and R ₉ is substituted with an ionic group, n is An integer from 0 to 3 When n is not substituted with an ionic group, n represents an integer of 1 to 3.)

(In the general formula (2), R ₁₁ represents an alkyl group, a cycloalkyl group, an aryl group, an arylalkyl group, an alkenyl group, or a heterocyclic group. * Represents a bond to an aromatic ring in the general formula (1). Represents the site.)   The content of the color material represented by the general formula (1) in the ink is 0.20 times or more and 3.00 times or less in terms of mass ratio with respect to the content of the yellow color material. Item 2. The red ink according to item 1.   The red ink according to claim 1, wherein the yellow color material is a color material having a disazo structure.   The red ink according to any one of claims 1 to 3, wherein a total content (% by mass) of the color material in the ink is 10.0% by mass or less based on the total mass of the ink.   An ink cartridge having an ink storage portion for storing ink, wherein the ink stored in the ink storage portion is the red ink according to any one of claims 1 to 4. .   An ink jet recording method including an image recording step of recording an image on a recording medium by ejecting ink by an ink jet method, wherein the red ink according to claim 1 is used in the image recording step. An ink jet recording method.   An ink jet recording apparatus comprising an ink containing portion for containing ink and a recording head for ejecting ink, wherein the ink contained in the ink containing portion is in any one of claims 1 to 4. An ink jet recording apparatus comprising the red ink described above.