JP2007125888A - Ink jet image recording method and image recording apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ink jet image recording method and an image recording apparatus which can record an image being little in unevenness, high in density and good in image quality. <P>SOLUTION: For a recording method for striking an ink-containing phthalocyanine dye of a specific structure obtained by dissolving or dispersing in water medium at an average striking speed of ≥2m/sec on recording material, the ink jet image recording method is featured by average drop striking speed of an ink drop having a small dropped volume being larger than the average dropping speed of an ink drop having a large dropping volume. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an inkjet image recording method capable of recording an image with little unevenness and high density and good image quality. Furthermore, the present invention relates to an inkjet image recording apparatus using the inkjet image recording method.

In recent years, with the spread of computers, ink jet printers are widely used for printing on paper, film, cloth and the like not only in offices but also at home.
Ink jet recording methods include a method of ejecting droplets by applying pressure with a piezo element, a method of ejecting droplets by generating bubbles in ink by heat, a method of using ultrasonic waves, or a droplet by electrostatic force. There is a method of sucking and discharging. As these inks for inkjet recording, water-based inks, oil-based inks, or solid (melting type) inks are used. Among these inks, water-based inks are mainly used from the viewpoints of production, handleability, odor, safety, and the like.

For the colorant used in these inks for ink jet recording, it has high solubility in solvents, high density recording is possible, hue is good, light, heat, air, ozone, water, Excellent fastness to chemicals, good fixability to image-receiving materials, low bleeding, excellent storage stability as ink, no toxicity, high purity, and low cost It is required to be able to do it. However, it is extremely difficult to search for colorants that meet these requirements at a high level. In particular, a colorant having a good cyan hue and excellent ozone fastness is strongly desired.
Various dyes and pigments have already been proposed and actually used for inkjet, but no colorant that satisfies all the requirements has yet been discovered. Conventionally well-known dyes and pigments having a color index (CI) number are difficult to achieve both hue and fastness required for ink jet recording inks.

On the other hand, the droplet ejection speed at which ink is ejected from nozzles when recording an image using these inks has a significant effect on the quality of the recorded image. When the droplet ejection speed is slow, the landing positions of the ink droplets on the recording material vary, and when recording with one color, a notch called jaggy occurs in the straight line portion. In addition, when recording a gradation image with multiple colors, there are problems that unevenness occurs in the color of the recorded image, or the image is not smooth and rough.
These problems are unlikely to occur when the droplet ejection speed is high, but in the case of low-density ink, it is necessary to obtain a predetermined density using many droplets. There is a disadvantage in that the recording time is longer than that of.

  An object of the present invention is to provide an inkjet image recording method and an image recording apparatus that record an image at a high density with little unevenness.

The above object of the present invention is achieved by the ink jet image recording method and ink jet image recording apparatus described below.
1. An average droplet ejection speed of 2 m / sec or more when ejecting an inkjet recording ink formed by dissolving or dispersing at least one dye represented by the following general formula (I) in an aqueous medium onto a recording material An inkjet image recording method characterized by the above.
Formula (I)

In the above general formula (I);
X ₁ , X ₂ , X ₃ and X ₄ are each independently —SO—Z, —SO ₂ —Z, —SO ₂ NR ₁ R ₂ , a sulfo group, —CONR ₁ R ₂ or —CO ₂ R. Represents ₁ .
Z is a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted group Represents a heterocyclic group. R ₁ and R ₂ are each independently a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted aralkyl group, substituted or unsubstituted It represents an unsubstituted aryl group or a substituted or unsubstituted heterocyclic group. When a plurality of Z are present, they may be the same or different.
Y ₁ , Y ₂ , Y ₃ and Y ₄ each independently represent a monovalent substituent.
In addition, when any _{one of} X _{1 to} X ₄ and Y _{1 to} Y ₄ is present, they may be the same or different.
a ₁ ~a ₄ and b ₁ ~b ₄ each represent a number of substituents X ₁ to X ₄ and _{Y 1 ~Y 4, a 1 ~a} 4 are each independently an integer of 0 to 4, All of them are not 0 at the same time, and b _{1 to} b ₄ are each independently an integer of 0 to 4.
M is a hydrogen atom, a metal atom or an oxide, hydroxide or halide thereof.

2. An inkjet image recording method for recording an image with a plurality of ink droplets having different droplet ejection volumes, wherein an average droplet ejection speed of an ink droplet having a small droplet ejection volume is greater than an average droplet ejection speed of an ink droplet having a large droplet ejection volume. 2. The inkjet image recording method as described in 1 above.
3. An inkjet image recording apparatus using the inkjet image recording method described in 1 or 2 above.

In the present invention, the following means are further preferably mentioned.
4). 3. The inkjet image recording method according to 1 or 2 above, wherein the dye represented by the general formula (I) is a dye represented by the following general formula (II).
Formula (II)

In the above general formula (II);
X < ₁₁ > -X < ₁₄ >, Y < ₁₁ > -Y < ₁₈ >, M is synonymous with X < ₁ > -X < ₄ >, Y < ₁ > -Y < ₄ >, M in general formula (I), respectively.
a ₁₁ ~a ₁₄ are each independently an integer of 1 or 2.

5. 3. The ink jet image recording method according to 1 or 2 above, wherein ink is deposited on the surface of the image receiving material of the image receiving material having an image receiving layer containing white inorganic pigment fine particles according to a recording signal.

  According to the present invention, unevenness and roughness of an image can be suppressed and a good image can be obtained at a high speed.

Hereinafter, the present invention will be described in more detail.
The inkjet image recording method of the present invention is characterized in that ink containing a dye represented by the above general formula (I) is ejected onto a recording material at an average droplet ejection speed of 2 m / sec or more. Among these, a preferable range of the average droplet ejection speed is 5 m / sec or more.
Here, the average droplet ejection speed was determined by dividing the distance from the nozzle surface of the print head to the recording material by the time from when the tip of the ink droplet started to eject from the nozzle surface until it landed on the recording material. Refers to speed.

As will be described later, the ink used in the present invention has a feature that the density is high, so that a high-density image can be recorded with a small amount of ink and is suitable for high-speed recording.
When recording with a small amount of ink, the ink droplets may be reduced or the number of ink droplets may be reduced, but when the number of ink droplets is reduced, the interval between the landing droplets on the recording material Therefore, there is a drawback that the fluctuation of the landing position becomes large and it is easy to be visually recognized as unevenness, and the roughness of the image becomes large.
On the other hand, when the ink droplets are made small, a good image can be obtained with a small roughness. However, if the ink ejection speed is slow, the kinetic energy of the ink droplets becomes small, causing disturbance factors, for example, landing on the recording material after being ejected from the nozzles. If there is air fluctuation or the like in the meantime, the speed and the ejection direction change due to the influence, the fluctuation of the landing position becomes large, and the image becomes uneven. FIG. 5 shows the relationship between ink droplet size (droplet ejection volume) and landing position fluctuation when the average droplet ejection speed is constant (2 m / sec). As shown in FIG. 5, this is the size of the ink droplet. The smaller the value, the more prominent.
However, as can be seen from FIG. 6 showing the relationship between the average droplet ejection speed and the landing position fluctuation when the droplet ejection volume is constant (2 pl), the larger the average droplet ejection speed, the smaller the landing position fluctuation. As in the present invention, high-density ink is ejected at an average droplet ejection speed of 2 m / sec or more, thereby making it possible to record a good image with less unevenness at high speed.

By the way, it is known that it is effective to mix different ink droplet sizes (droplet ejection volumes) and eject droplets in order to express gradations finely and to record an image at a high density and at high speed. Technical Information Association, “Development of high-quality, high-speed technology and related materials for inkjet recording”, p52).
As described above, ink droplets with a small droplet ejection volume tend to have larger landing position fluctuations, and it is necessary to increase the average droplet ejection speed. By setting so as to be larger than the average droplet ejection speed of an ink droplet having a large volume, a good image with less unevenness and fine gradation can be recorded at high speed.

In the present invention, there is no limitation on the ink jet recording method, and a known method, for example, a charge control method for ejecting ink using electrostatic attraction, a drop-on-demand method (pressure pulse method) using vibration pressure of a piezo element. , An acoustic ink jet method in which an electrical signal is converted into an acoustic beam, and ink is ejected by using the radiation pressure, and an ink is ejected by using a radiation pressure. Registered trademark)) method.
Inkjet recording methods use 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 inks. The method is included.

  FIG. 1 is a general schematic diagram of an ink jet printer. First, when an image signal to be printed is input by the printer control unit, the droplet ejection size, droplet ejection speed, and droplet ejection frequency are determined by the printer control unit, and the droplet ejection size, droplet ejection speed, droplet ejection are determined by each control unit. A signal for operating the frequency is created, and a drive signal for the print head is created. The drive signal is supplied from the print head drive unit, and the print head ejects ink according to the drive signal to print an image.

  The print head drive system according to the drive signal differs depending on the printer recording system. The average ink droplet ejection speed, which is a feature of the present invention, is controlled by controlling the shape and amplitude of the waveform driving the print head. It can be carried out.

The driving of the print head by the drop ion demand method using a piezo element will be described in more detail.
As shown in FIG. 2 (a), the piezo element is arranged at a position in contact with an ink passage for guiding ink to the nozzle plate. As is well known, the piezo element is an element utilizing the fact that the crystal structure is distorted by application of a voltage, and its responsiveness is extremely fast. As shown in FIG. 2B, when a voltage (driving signal) is applied to the piezo element, the piezo element extends for the application time and deforms the side wall of the ink passage. As a result, the volume of the ink passage contracts according to the expansion of the piezo element, and the ink corresponding to the contraction is ejected from the nozzle as ink droplets (FIG. 2 (c)).
Since the ink droplet ejection speed varies depending on the speed and size of expansion of the piezo element, the average ink ejection speed can be determined by the waveform of the drive signal. The ink droplet volume can also be determined by the amplitude of the drive signal waveform.
Also, by using a plurality of drive waveforms properly, it is possible to eject a plurality of ink droplets having different droplet ejection volumes and average droplet ejection speeds with the same print head.

  Examples of means for measuring the ink droplet size (droplet ejection volume) include those shown in FIG. The print head is driven by a head drive signal for ejecting ink, and a circuit that generates a time delay of a predetermined time is adjusted, and the ink droplet is illuminated by a lamp for a short time to the flying ink droplet. Is imaged with a CCD camera at a predetermined magnification. FIG. 4 shows a photographed image. The diameter R of the ink droplet can be obtained from the photographed image, and the volume V can be obtained from the following equation.

  The average droplet ejection speed is determined by measuring where the ink droplets are located after a predetermined time from the drive signal with the above CCD camera, so that the print head is driven and the ink droplets start flying from the nozzle surface. The time until the ink droplet comes to the position corresponding to the distance between the head and the recording material can be known and determined.

  With respect to the configuration of the printing apparatus and the printer of the present invention, for example, a mode as disclosed in JP-A-11-170527 is preferable. As the ink cartridge, for example, the one disclosed in Japanese Patent Laid-Open No. 5-229133 is suitable. With respect to the suction and the configuration of a cap or the like that covers the print head at that time, for example, the one disclosed in JP-A-7-276671 is suitable. Further, it is preferable that a filter for eliminating bubbles as disclosed in JP-A-9-277552 is provided in the vicinity of the head. The nozzle surface is preferably subjected to water repellent treatment as described in Japanese Patent Application No. 2001-16738. The application may be a printer connected to a computer or an apparatus specialized for printing photographs.

Next, the ink for ink jet recording used in the present invention will be described.
The ink for inkjet recording of the present invention contains at least one phthalocyanine dye represented by the above general formula (I).
Phthalocyanine dyes are known as fast dyes, but are known to be inferior in fastness to ozone gas when used as inkjet recording dyes.
In the present invention, it is desirable to introduce an electron withdrawing group into the phthalocyanine skeleton to make the oxidation potential nobler than 1.0 V (vs SCE) in order to lower the reactivity with ozone, which is an electrophile. The oxidation potential is preferably as noble, more preferably noble than the oxidation potential of 1.1 V (vs SCE), and most preferably nob of 1.2 V (vs SCE).

  A person skilled in the art can easily measure the value of the oxidation potential (Eox). Regarding this method, see, for example, P.I. Delahay, “New Instrumental Methods in Electrochemistry” (published by Interscience Publishers, 1954). J. et al. "Electrochemical Methods" by Bard et al. (Published by John Wiley & Sons, 1980), "Electrochemical Measurement Method" by Akira Fujishima et al. (Published by Gihodo Publishing Co., Ltd., 1984), and the like.

Specifically, the oxidation potential is 1 × 10 ⁻⁴ to 1 × 10 ^{−6 in} a solvent such as dimethylformamide or acetonitrile containing a supporting electrolyte such as sodium perchlorate or tetrapropylammonium perchlorate. It is dissolved at a concentration of mol / liter and measured as a value for SCE (saturated calomel electrode) using cyclic voltammetry or direct current polarography. This value may deviate by several tens of millivolts due to the influence of the liquid potential difference or the liquid resistance of the sample solution. However, the reproducibility of the potential can be ensured by inserting a standard sample (for example, hydroquinone).
In order to uniquely define the potential, in the present invention, a direct current polarizer is used in dimethylformamide containing 0.1 moldm ⁻³ tetrapropylammonium perchlorate as a supporting electrolyte (the concentration of the dye is 0.001 moldm ⁻³ ). The value (vs SCE) measured by ography is taken as the oxidation potential of the dye.

The value of Eox (oxidation potential) represents the ease of transfer of electrons from the sample to the electrode, and the larger the value (the higher the oxidation potential), the less transfer of electrons from the sample to the electrode, in other words, less oxidation. Represents that. In relation to the structure of the compound, the oxidation potential becomes more noble by introducing an electron withdrawing group, and the oxidation potential becomes lower by introducing an electron donating group. In the present invention, in order to lower the reactivity with ozone which is an electrophile, it is desirable to introduce an electron withdrawing group into the phthalocyanine skeleton to make the oxidation potential more noble. Therefore, by using Hammett's substituent constant σp value, which is a measure of the electron withdrawing property and electron donating property of a substituent, by introducing a substituent having a large σp value such as a sulfinyl group, a sulfonyl group, and a sulfamoyl group. It can be said that the oxidation potential can be made more noble.
Also for the reason of such potential adjustment, it is preferable to use the phthalocyanine dye represented by the general formula (I).

In the general formula (I), X ₁ , X ₂ , X ₃ and X ₄ are each independently —SO—Z, —SO ₂ —Z, —SO ₂ NR ₁ R ₂ , a sulfo group, —CONR ₁ R _2, or a -CO ₂ R _1. Among these substituents, —SO—Z, —SO ₂ —Z, —SO ₂ NR ₁ R ₂ and —CONR ₁ R ₂ are preferable, and —SO ₂ —Z and —SO ₂ NR ₁ R ₂ are particularly preferable. , -SO ₂ -Z is most preferable. Here, when any one of a _{1 to} a ₄ representing the number of substituents represents a number of 2 or more, a plurality of X _{1 to} X ₄ may be the same or different, and each independently Represents any group of X ₁ , X ₂ , X ₃ and X ₄ may each be the same substituent, or for example, X ₁ , X ₂ , X ₃ and X ₄ are all —SO ₂ —Z, and As in the case where each Z includes different ones, they may be the same type of substituents but may be partially different from each other, or may be different from each other, for example, —SO ₂ —Z and —SO _2. NR ₁ R ₂ may be included.

Z is independently substituted or unsubstituted alkyl group, substituted or unsubstituted cycloalkyl group, substituted or unsubstituted alkenyl group, substituted or unsubstituted aralkyl group, substituted or unsubstituted aryl group, substituted Alternatively, it represents an unsubstituted heterocyclic group. Preferred are a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, and a substituted or unsubstituted heterocyclic group. Among them, a substituted alkyl group, a substituted aryl group, and a substituted heterocyclic group are most preferred.
R ₁ and R ₂ are each independently a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted aralkyl group, substituted or unsubstituted It represents an unsubstituted aryl group or a substituted or unsubstituted heterocyclic group. Of these, a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, and a substituted or unsubstituted heterocyclic group are preferable. Among them, a hydrogen atom, a substituted alkyl group, a substituted aryl group, and a substituted heterocyclic group are preferable. A cyclic group is more preferable. However, it is not preferred that both R ₁ and R ₂ are hydrogen atoms.

The substituted or unsubstituted alkyl group represented by R ₁ , R ₂ and Z is preferably an alkyl group having 1 to 30 carbon atoms. In particular, a branched alkyl group is preferred because of increasing the solubility of the dye and the ink stability, and particularly preferred is a case having an asymmetric carbon (use in racemic form). Examples of the substituent include the same substituents as those described later when Z, R ₁ , R ₂ , Y ₁ , Y ₂ , Y ₃ and Y ₄ can further have a substituent. Of these, a hydroxyl group, an ether group, an ester group, a cyano group, an amide group, and a sulfonamide group are particularly preferable because they enhance the association of the dye and improve the fastness. In addition, you may have a halogen atom and an ionic hydrophilic group. The number of carbon atoms of the alkyl group does not include the carbon atom of the substituent, and the same applies to other groups.

The substituted or unsubstituted cycloalkyl group represented by R _1, R ₂ and Z, the number of carbon atoms is preferably a cycloalkyl group having 5 to 30. In particular, the case of having an asymmetric carbon (use in a racemic form) is particularly preferable because of increasing the solubility of the dye and the ink stability. Examples of the substituent include the same substituents as those described later when Z, R ₁ , R ₂ , Y ₁ , Y ₂ , Y ₃ and Y ₄ can further have a substituent. Among these, a hydroxyl group, an ether group, an ester group, a cyano group, an amide group, and a sulfonamide group are particularly preferable because they increase the association property of the dye and improve the fastness. In addition, you may have a halogen atom and an ionic hydrophilic group.

The substituted or unsubstituted alkenyl group represented by R ₁ , R ₂ and Z is preferably an alkenyl group having 2 to 30 carbon atoms. In particular, a branched alkenyl group is preferred because it increases the solubility of the dye and the ink stability, and particularly preferred is a case having an asymmetric carbon (use in a racemic form). Examples of the substituent include the same substituents as those described later when Z, R ₁ , R ₂ , Y ₁ , Y ₂ , Y ₃ and Y ₄ can further have a substituent. Among these, a hydroxyl group, an ether group, an ester group, a cyano group, an amide group, and a sulfonamide group are particularly preferable because they increase the association property of the dye and improve the fastness. In addition, you may have a halogen atom and an ionic hydrophilic group.

The substituted or unsubstituted aralkyl group represented by R ₁ , R ₂ and Z is preferably an aralkyl group having 7 to 30 carbon atoms. In particular, a branched aralkyl group is preferred because it increases the solubility of the dye and the ink stability, and particularly preferred is a case having an asymmetric carbon (use in a racemic form). Examples of the substituent include the same substituents as those described later when Z, R ₁ , R ₂ , Y ₁ , Y ₂ , Y ₃ and Y ₄ can further have a substituent. Among these, a hydroxyl group, an ether group, an ester group, a cyano group, an amide group, and a sulfonamide group are particularly preferable because they increase the association property of the dye and improve the fastness. In addition, you may have a halogen atom and an ionic hydrophilic group.

The substituted or unsubstituted aryl group represented by R ₁ , R ₂ and Z is preferably an aryl group having 6 to 30 carbon atoms. Examples of the substituent include the same substituents as those described later when Z, R ₁ , R ₂ , Y ₁ , Y ₂ , Y ₃ and Y ₄ can further have a substituent. Among these, an electron-withdrawing group is particularly preferable because the oxidation potential of the dye is noble and fastness is improved. Examples of the electron-withdrawing group include those having a positive Hammett's substituent constant σp value. Among them, a halogen atom, a heterocyclic group, a cyano group, a carboxyl group, an acylamino group, a sulfonamido group, a sulfamoyl group, a carbamoyl group, a sulfonyl group, an imide group, an acyl group, a sulfo group, and a quaternary ammonium group are preferable, and a cyano group , Carboxyl group, sulfamoyl group, carbamoyl group, sulfonyl group, imide group, acyl group, sulfo group, and quaternary ammonium group are more preferable.

The heterocyclic group represented by R ₁ , R ₂ and Z is preferably a 5-membered or 6-membered ring, which may be further condensed. Further, it may be an aromatic heterocyclic ring or a non-aromatic heterocyclic ring. The heterocyclic groups represented by R ₁ , R ₂ and Z are exemplified below in the form of a heterocyclic ring with the substitution position omitted, but the substitution position is not limited. It is possible to substitute at position 3, 3 and 4. Pyridine, pyrazine, pyrimidine, pyridazine, triazine, quinoline, isoquinoline, quinazoline, cinnoline, phthalazine, quinoxaline, pyrrole, indole, furan, benzofuran, thiophene, benzothiophene, pyrazole, imidazole, benzimidazole, triazole, oxazole, benzoxazole, thiazole Benzothiazole, isothiazole, benzisothiazole, thiadiazole, isoxazole, benzisoxazole, pyrrolidine, piperidine, piperazine, imidazolidine, thiazoline and the like. Among them, an aromatic heterocyclic group is preferable, and preferable examples thereof are exemplified in the same manner as described above. Examples include isothiazole and thiadiazole. They may have a substituent, and as examples of the substituent, Z, R ₁ , R ₂ , Y ₁ , Y ₂ , Y ₃ and Y ₄ described later can further have a substituent. Examples are the same as the substituents in the case. Preferred substituents are the same as those of the aryl group, and more preferred substituents are the same as the more preferred substituent of the aryl group.

Y ₁ , Y ₂ , Y ₃ and Y ₄ are each independently a hydrogen atom, halogen atom, alkyl group, cycloalkyl group, alkenyl group, aralkyl group, aryl group, heterocyclic group, cyano group, hydroxyl group, nitro Group, amino group, alkylamino group, alkoxy group, aryloxy group, acylamino group, arylamino group, ureido group, sulfamoylamino group, alkylthio group, arylthio group, alkoxycarbonylamino group, sulfonamido group, carbamoyl group, Sulfamoyl group, sulfonyl group, alkoxycarbonyl group, heterocyclic oxy group, azo group, acyloxy group, carbamoyloxy group, silyloxy group, aryloxycarbonyl group, aryloxycarbonylamino group, imide group, heterocyclic thio group, phosphoryl group, Acyl group, carboxyl A group or a sulfo group, each of which may further have a substituent.

  Among these, a hydrogen atom, a halogen atom, an alkyl group, an aryl group, a cyano group, an alkoxy group, an amide group, a ureido group, a sulfonamide group, a carbamoyl group, a sulfamoyl group, an alkoxycarbonyl group, a carboxyl group, and a sulfo group are preferable. In particular, a hydrogen atom, a halogen atom, a cyano group, a carboxyl group and a sulfo group are preferable, and a hydrogen atom is most preferable.

When Z, R ₁ , R ₂ , Y ₁ , Y ₂ , Y _3, and Y ₄ are groups that can further have a substituent, they may further have the following substituents.

  A linear or branched alkyl group having 1 to 12 carbon atoms, a linear or branched aralkyl group having 7 to 18 carbon atoms, a linear or branched alkenyl group having 2 to 12 carbon atoms, and a linear chain having 2 to 12 carbon atoms Or a branched alkynyl group, a linear or branched cycloalkyl group having 3 to 12 carbon atoms, a linear or branched cycloalkenyl group having 3 to 12 carbon atoms (the above groups having a branched chain are dissolved in the dye) Preferred are those having an asymmetric carbon, and particularly preferred are those having an asymmetric carbon, such as methyl, ethyl, propyl, isopropyl, sec-butyl, t-butyl, 2- Ethylhexyl, 2-methylsulfonylethyl, 3-phenoxypropyl, trifluoromethyl, cyclopentyl), halogen atom (eg, chlorine atom, bromine atom), aryl group (For example, phenyl, 4-t-butylphenyl, 2,4-di-t-amylphenyl), a heterocyclic group (for example, imidazolyl, pyrazolyl, triazolyl, 2-furyl, 2-thienyl, 2-pyrimidinyl, 2- Benzothiazolyl),

Cyano group, hydroxyl group, nitro group, carboxy group, amino group, alkyloxy group (eg, methoxy, ethoxy, 2-methoxyethoxy, 2-methanesulfonylethoxy), aryloxy group (eg, phenoxy, 2-methylphenoxy, 4-t-butylphenoxy, 3-nitrophenoxy, 3-t-butyloxycarbamoylphenoxy, 3-methoxycarbamoyl), acylamino groups (eg, acetamide, benzamide, 4- (3-t-butyl-4-hydroxyphenoxy) Butanamide), alkylamino groups (eg, methylamino, butylamino, diethylamino, methylbutylamino), anilino groups (eg, phenylamino, 2-chloroanilino, ureido groups (eg, phenylureido, methylureido, N, N-) Butylureido), sulfamoylamino group (eg, N, N-dipropylsulfamoylamino), alkylthio group (eg, methylthio, octylthio, 2-phenoxyethylthio), arylthio group (eg, phenylthio, 2-butoxy- 5-t-octylphenylthio, 2-carboxyphenylthio), alkyloxycarbonylamino group (for example, methoxycarbonylamino), sulfonamide group (for example, methanesulfonamide, benzenesulfonamide, p-toluenesulfonamide),

Carbamoyl group (for example, N-ethylcarbamoyl, N, N-dibutylcarbamoyl), sulfamoyl group (for example, N-ethylsulfamoyl, N, N-dipropylsulfamoyl, N-phenylsulfamoyl), sulfonyl group ( For example, methanesulfonyl, octanesulfonyl, benzenesulfonyl, toluenesulfonyl), alkyloxycarbonyl group (for example, methoxycarbonyl, butyloxycarbonyl), heterocyclic oxy group (for example, 1-phenyltetrazol-5-oxy, 2-tetrahydropyrani) Oxy), azo group (for example, phenylazo, 4-methoxyphenylazo, 4-pivaloylaminophenylazo, 2-hydroxy-4-propanoylphenylazo), acyloxy group (for example, acetoxy), carbamoylo Shi group (e.g., N- methylcarbamoyloxy, N- phenylcarbamoyloxy),

Silyloxy groups (for example, trimethylsilyloxy, dibutylmethylsilyloxy), aryloxycarbonylamino groups (for example, phenoxycarbonylamino), imide groups (for example, N-succinimide, N-phthalimide), heterocyclic thio groups (for example, 2- Benzothiazolylthio, 2,4-di-phenoxy-1,3,5-triazole-6-thio, 2-pyridylthio), sulfinyl group (eg 3-phenoxypropylsulfinyl), phosphonyl group (eg phenoxyphosphonyl) , Octyloxyphosphonyl, phenylphosphonyl), aryloxycarbonyl group (for example, phenoxycarbonyl), acyl group (for example, acetyl, 3-phenylpropanoyl, benzoyl), ionic hydrophilic group (for example, carboxyl group, sulfo group) , Phosphono group and a quaternary ammonium group).

When the phthalocyanine dye represented by the general formula (I) is water-soluble, it preferably has an ionic hydrophilic group. Examples of the ionic hydrophilic group include a sulfo group, a carboxyl group, a phosphono group, and a quaternary ammonium group. As the ionic hydrophilic group, a carboxyl group, a phosphono group, and a sulfo group are preferable, and a carboxyl group and a sulfo group are particularly preferable. The carboxyl group, phosphono group, and sulfo group may be in the form of a salt. Examples of counter ions that form a salt include ammonium ions, alkali metal ions (eg, lithium ions, sodium ions, potassium ions), and organic cations. (Eg, tetramethylammonium ion, tetramethylguanidinium ion, tetramethylphosphonium). Among the counter ions, an alkali metal salt is preferable, and a lithium salt is particularly preferable because it increases the solubility of the dye and improves the ink stability.
The number of ionic hydrophilic groups is preferably at least two in one molecule of phthalocyanine dye, and particularly preferably at least two sulfo groups and / or carboxyl groups.

a ₁ ~a ₄ and b ₁ ~b ₄ each represent the number of substituents of X ₁ to X ₄ and Y ₁ to Y _4. a _{1 to} a ₄ each independently represents an integer of 0 to 4, but they are not all 0 at the same time. b ₁ ~b ₄ each independently represents an integer of 0-4. When any of a _{1 to} a ₄ and b _{1 to} b ₄ is an integer of 2 or more, any one of X _{1 to} X ₄ and Y _{1 to} Y ₄ is present, May be the same or different.

a ₁ and b ₁ satisfy the relationship of a ₁ + b ₁ = 4. Particularly preferred, a ₁ represents 1 or 2, b ₁ is the combination that represents a 3 or 2, Among them, a ₁ represents 1, b ₁ is the most preferred combination representing the three.
Each combination of a ₁ and b ₁ , a ₁ and b ₁ , and a ₁ and b ₁ has the same relationship as the combination of a ₁ and b ₁ , and preferred combinations are also the same.

M represents a hydrogen atom, a metal element or an oxide, hydroxide or halide thereof.
What is preferable as M is a metal element other than a hydrogen atom, such as Li, Na, K, Mg, Ti, Zr, V, Nb, Ta, Cr, Mo, W, Mn, Fe, Co, Ni, Ru, Rh, Pd, Os, Ir, Pt, Cu, Ag, Au, Zn, Cd, Hg, Al, Ga, In, Si, Ge, Sn, Pb, Sb, Bi and the like can be mentioned. Preferred examples of the oxide include VO and GeO.
Moreover, as a hydroxide, Si (OH) ₂ , Cr (OH) ₂ , Sn (OH) _2, etc. are mentioned preferably. Further, examples of the halide include AlCl, SiCl ₂ , VCl, VCl ₂ , VOCl, FeCl, GaCl, and ZrCl. Of these, Cu, Ni, Zn, Al and the like are preferable, and Cu is most preferable.

  In addition, Pc (phthalocyanine ring) may form a dimer (for example, Pc-MLM-Pc) or a trimer via L (a divalent linking group), and M at that time is Each may be the same or different.

The divalent linking group represented by L includes an oxy group —O—, a thio group —S—, a carbonyl group —CO—, a sulfonyl group —SO ₂ —, an imino group —NH—, a methylene group —CH ₂ —, And a group formed by combining them is preferred.

  As for the preferred combination of substituents of the compound represented by the general formula (I), a compound in which at least one of various substituents is the preferred group is preferred, and more various substituents are preferred groups. Certain compounds are more preferred, and compounds in which all substituents are the preferred groups are most preferred.

Among the phthalocyanine dyes represented by the general formula (I), a phthalocyanine dye having a structure represented by the general formula (II) is more preferable. The phthalocyanine dye represented by formula (II) of the present invention will be described in detail below.

In the general formula _{(II), X 11 ~X 14} , Y 11 ~Y 18 is X ₁ to X in the general formula (I) _4, and Y ₁ to Y ₄ are respectively the same, preferred examples are also the same is there. Moreover, M is synonymous with M in general formula (I), and its preferable example is also the same.

In the general formula (II), a _{11 to} a ₁₄ are each independently an integer of 1 or 2, preferably satisfy 4 ≦ a ₁₁ + a ₁₂ + a ₁₃ + a ₁₄ ≦ 6, and particularly preferably a ₁₁ = a _{This is when 12} = a ₁₃ = a ₁₄ = 1.

X ₁₁ , X ₁₂ , X ₁₃ and X ₁₄ may each be the same substituent, or for example, X ₁ , X ₂ , X ₃ and X ₄ are all —SO ₂ —Z, and each Z May be the same type of substituent, but may be partially different from each other, or different substituents may be represented by, for example, —SO ₂ —Z and —SO ₂ NR _1. R ₂ may be included.
Among the phthalocyanine dyes represented by the general formula (II), particularly preferred combinations of substituents are as follows.

X _{11 to} X ₁₄ are each independently preferably —SO—Z, —SO ₂ —Z, —SO ₂ NR ₁ R ₂ or —CONR ₁ R ₂ , particularly —SO ₂ —Z or —SO ₂ NR. ₁ R ₂ is preferred, and —SO ₂ —Z is most preferred.

  Z is independently preferably a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heterocyclic group, and among them, a substituted alkyl group, a substituted aryl group, or a substituted heterocyclic group Is most preferred. In particular, the case of having an asymmetric carbon in the substituent (use in a racemic form) is preferable because of increasing the solubility of the dye and the ink stability. In addition, for the reason of increasing the association property and improving the fastness, it is preferable that a hydroxyl group, an ether group, an ester group, a cyano group, an amide group, or a sulfonamide group have in the substituent.

R ₁ and R ₂ are each independently preferably a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heterocyclic group, and among them, a hydrogen atom and a substituted alkyl A group, a substituted aryl group, and a substituted heterocyclic group are more preferable. However, it is not preferred that R ₁ and R ₂ are both hydrogen atoms. In particular, the case of having an asymmetric carbon in the substituent (use in a racemic form) is preferable because of increasing the solubility of the dye and the ink stability. In addition, for the reason of increasing the association property and improving the fastness, it is preferable that a hydroxyl group, an ether group, an ester group, a cyano group, an amide group, or a sulfonamide group have in the substituent.

Y _{11 to} Y ₁₈ are each independently a hydrogen atom, halogen atom, alkyl group, aryl group, cyano group, alkoxy group, amide group, ureido group, sulfonamido group, carbamoyl group, sulfamoyl group, alkoxycarbonyl group, carboxyl And a sulfo group are preferable, and a hydrogen atom, a halogen atom, a cyano group, a carboxyl group, or a sulfo group is particularly preferable, and a hydrogen atom is most preferable.
a _{11 to} a ₁₄ are each independently preferably 1 or 2, and particularly preferably all 1.
M represents a hydrogen atom, a metal element or an oxide, hydroxide or halide thereof, and Cu, Ni, Zn and Al are particularly preferable, and Cu is particularly preferable.

When the phthalocyanine dye represented by the general formula (II) is water-soluble, it preferably has an ionic hydrophilic group. Examples of the ionic hydrophilic group include a sulfo group, a carboxyl group, a phosphono group, and a quaternary ammonium group. As the ionic hydrophilic group, a carboxyl group, a phosphono group, and a sulfo group are preferable, and a carboxyl group and a sulfo group are particularly preferable. The carboxyl group, phosphono group, and sulfo group may be in the form of a salt. Examples of counter ions that form a salt include ammonium ions, alkali metal ions (eg, lithium ions, sodium ions, potassium ions), and organic cations. (Eg, tetramethylammonium ion, tetramethylguanidinium ion, tetramethylphosphonium). Among the counter ions, an alkali metal salt is preferable, and a lithium salt is particularly preferable because it increases the solubility of the dye and improves the ink stability.
As the number of ionic hydrophilic groups, it is preferable to have at least two phthalocyanine dye molecules, and it is particularly preferable to have at least two sulfo groups and / or carboxyl groups.

  Regarding the preferred combination of substituents of the compound represented by the general formula (II), a compound in which at least one of various substituents is the preferred group is preferred, and more various substituents are preferred groups. Certain compounds are more preferred, and compounds in which all substituents are the preferred groups are most preferred.

The chemical structure of the phthalocyanine dye of the present invention includes an electron-withdrawing group such as a sulfinyl group, a sulfonyl group, and a sulfamoyl group, at least one for each of the four benzene rings of phthalocyanine, and the σp value of the substituent of the entire phthalocyanine skeleton. It is preferable to introduce so that it may become 1.6 or more in total.
Hammett's substituent constant σp value will be described briefly. Hammett's rule is a method described in 1935 by L. E. in order to quantitatively discuss the effect of substituents on the reaction or equilibrium of benzene derivatives. P. A rule of thumb proposed by Hammett, which is widely accepted today. Substituent constants determined by Hammett's rule include a σp value and a σm value, and these values can be found in many general books. A. Dean, “Lange's Handbook of Chemistry”, 12th edition, 1979 (Mc Graw-Hill) and “Chemicals” special edition, 122, 96-103, 1979 (Nankodo).

  The phthalocyanine derivative represented by the general formula (I) inevitably has different introduction positions and numbers of substituents Xn (n = 1 to 4) and Ym (m = 1 to 4) depending on the synthesis method. Mixtures are common, so the general formula often represents a statistical average of these analog mixtures. In the present invention, it has been found that a specific mixture is particularly preferable when these analog mixtures are classified into the following three types. That is, the phthalocyanine dye analog mixtures represented by the general formulas (I) and (II) are defined by classifying them into the following three types based on the substitution positions.

(1) β-position substitution type: phthalocyanine dye having a specific substituent at the 2 and / or 3 position, 6 and / or 7 position, 10 and / or 11 position, 14 and / or 15 position.
(2) α-position substitution type: phthalocyanine dye having specific substituents at 1 and 4 position, 5 and or 8 position, 9 and or 12 position, 13 and or 16 position (3) α, β-position mixed Substitution type: phthalocyanine dye having a specific substituent without regularity at positions 1 to 16

  In the present specification, when describing derivatives of phthalocyanine dyes having different structures (particularly, different substitution positions), the β-position substitution type, α-position substitution type, and α, β-position mixed substitution type are used. .

  Examples of the phthalocyanine derivative used in the present invention include “Phthalocyanine—Chemistry and Function” (P. 1-62), C.K. C. Leznoff-A. B. P. Lever co-authored by VCH and published in 'Phthalogicanes-Properties and Applications' (P. 1-54), etc., can be synthesized by combining quoted or similar methods.

  The phthalocyanine compounds represented by the general formula (I) of the present invention are described in World Patent Nos. 00/17275, 00/08103, 00/08101, 98/41853, and JP-A-10-36471. As described above, for example, it can be synthesized through sulfonation, sulfonyl chlorideation, and amidation reaction of an unsubstituted phthalocyanine compound. In this case, sulfonation can occur at any position of the phthalocyanine nucleus, and the number of sulfonation is difficult to control. Therefore, when a sulfo group is introduced under such reaction conditions, the position and number of the sulfo group introduced into the product cannot be specified, and a mixture in which the number of substituents and the substitution position are different is always given. Therefore, when synthesizing the compound of the present invention using it as a raw material, the number and substitution position of the heterocyclic substituted sulfamoyl group cannot be specified, so the compound of the present invention includes several types of compounds having different numbers of substituents and substitution positions. Α, β-position mixed substitution mixture.

  As described above, for example, when a large number of electron withdrawing groups such as sulfamoyl groups are introduced into the phthalocyanine nucleus, the oxidation potential becomes more noble and the ozone resistance is enhanced. According to the above synthesis method, it is inevitable that a small amount of electron-withdrawing groups are introduced, that is, a phthalocyanine dye having a lower oxidation potential is mixed. Therefore, in order to improve ozone resistance, it is more preferable to use a synthesis method that suppresses the formation of a compound having a lower oxidation potential.

  The phthalocyanine compound represented by the general formula (II) of the present invention is, for example, a phthalonitrile derivative (compound P) and / or a diiminoisoindoline derivative (compound Q) represented by the following formula represented by the general formula (III). Or a tetrasulfophthalocyanine compound obtained by reacting a 4-sulfophthalonitrile derivative (compound R) represented by the following formula with a metal derivative represented by the general formula (III): can do.

In the above formulas, Xp corresponds to X ₁₁ , X ₁₂ , X ₁₃ or X ₁₄ in the general formula (II). Yq and Yq ′ correspond to Y ₁₁ , Y ₁₂ , Y ₁₃ , Y ₁₄ , Y ₁₅ , Y ₁₆ , Y ₁₇ or Y ₁₈ in the general formula (II), respectively. In compound R, M ′ represents a cation.
Examples of the cation represented by M ′ include alkali metal ions such as Li, Na and K, or organic cations such as triethylammonium ion and pyridinium ion.

General formula (III): M- (Y) d
In the general formula (III), M has the same meaning as M in the general formulas (I) and (II), and Y is a monovalent or divalent coordination such as a halogen atom, an acetate anion, acetylacetonate, or oxygen. Child is shown, d is an integer of 1-4.

  That is, according to the above synthesis method, a specific number of desired substituents can be introduced. In particular, when a large number of electron withdrawing groups are to be introduced in order to make the oxidation potential noble as in the present invention, the above synthesis method is the method already described for synthesizing the phthalocyanine compound of the general formula (I). It is extremely superior compared to

  The thus obtained phthalocyanine compound represented by the general formula (II) is usually a mixture of compounds represented by the following general formulas (a) -1 to (a) -4 which are isomers at each substitution position of Xp. That is, the β-position substitution type.

In the above synthesis method, if the same Xp is used, a β-position substituted phthalocyanine dye in which X ₁₁ , X ₁₂ , X ₁₃ and X ₁₄ are the same substituents can be obtained. On the other hand, by using different combinations of Xp, it is possible to synthesize dyes having the same type of substituents but partially different from each other, or dyes having different types of substituents. . Among the dyes of the general formula (II), these dyes having mutually different electron-withdrawing substituents are particularly preferable because they can adjust the solubility of the dye, the associability, the stability with time of the ink, and the like.

  In the present invention, it is found that it is very important to improve the fastness that the oxidation potential is noble than 1.0 V (vs SCE) in any substitution type. It was completely unpredictable from the prior art. Although the cause is unknown in detail, the β-position substitution type is clearly superior in terms of hue, light fastness, ozone gas resistance, etc., compared to the α, β-position mixed substitution type. there were.

  Specific examples (Exemplary Compounds I-1 to I-12 and 101 to 190) of the phthalocyanine dyes represented by the general formulas (I) and (II) are shown below. The phthalocyanine dye used in the present invention is as follows. It is not limited to the example.

The structures of the phthalocyanine compounds represented by M-Pc (Xp ₁ ) m (Xp ₂ ) n in Tables 8 to 11 are as follows.

  The phthalocyanine dye represented by the general formula (I) can be synthesized according to the aforementioned patent. Moreover, the phthalocyanine dye represented by the general formula (II) is not limited to the synthesis method described above, and JP-A Nos. 2001-226275, 2001-96610, 2001-47013, and 2001-193638. It can be synthesized by the method described in 1. Further, the starting material, the dye intermediate and the synthesis route are not limited to these.

The ink for inkjet recording used in the present invention (hereinafter sometimes referred to as the ink of the present invention) preferably contains 0.2 to 20% by mass of the phthalocyanine dye, and more preferably 0.5 to 15% by mass. %contains.
The phthalocyanine dye has a characteristic that a high molecular extinction coefficient is obtained and a high concentration can be obtained in an equal amount.

  In order to obtain a full color image together with the phthalocyanine dye, other inks may be used in combination with the ink for inkjet recording of the present invention. The following can be mentioned as an example of the dye which can be used together.

  Examples of yellow dyes include phenols, naphthols, anilines, pyrazolones, pyridones, aryl or heteryl azo dyes having open-chain active methylene compounds as coupling components; for example, open-chain active methylene compounds as coupling components. Azomethine dyes; methine dyes such as benzylidene dyes and monomethine oxonol dyes; quinone dyes such as naphthoquinone dyes and anthraquinone dyes, and other dye species such as quinophthalone dyes, nitro-nitroso dyes And dyes, acridine dyes, acridinone dyes and the like. These dyes may be those that exhibit yellow only after a part of the chromophore is dissociated, in which case the counter cation may be an alkali metal or an inorganic cation such as ammonium, pyridinium, It may be an organic cation such as a quaternary ammonium salt, and further may be a polymer cation having them in a partial structure.

  Examples of magenta dyes include aryl or heteryl azo dyes having phenols, naphthols, and anilines as coupling components; azomethine dyes having pyrazolones and pyrazolotriazoles as coupling components; for example, arylidene dyes, styryl dyes, and merocyanine Dyes, methine dyes such as oxonol dyes; carbonium dyes such as diphenylmethane dyes, triphenylmethane dyes, xanthene dyes, quinone dyes such as naphthoquinone, anthraquinone, anthrapyridone, etc. And ring dyes. These dyes may exhibit magenta only after part of the chromophore is dissociated, and the counter cation in that case may be an alkali metal or an inorganic cation such as ammonium, pyridinium, It may be an organic cation such as a quaternary ammonium salt, and further may be a polymer cation having them in a partial structure.

Examples of cyan dyes include azomethine dyes such as indoaniline dyes and indophenol dyes; polymethine dyes such as cyanine dyes, oxonol dyes and merocyanine dyes; carbonium dyes such as diphenylmethane dyes, triphenylmethane dyes and xanthene dyes; phthalocyanine Dyes; anthraquinone dyes; For example, aryl or heteryl azo dyes having phenols, naphthols and anilines as coupling components, and indigo / thioindigo dyes can be mentioned. These dyes may exhibit cyan only after a part of the chromophore is dissociated, and the counter cation in that case may be an alkali metal or an inorganic cation such as ammonium, pyridinium, It may be an organic cation such as a quaternary ammonium salt, and further may be a polymer cation having them in a partial structure.
Black dyes such as polyazo dyes can also be used.

The dye containing the phthalocyanine dye used in the present invention is substantially water-soluble or water-dispersible. Specifically, the solubility of the dye in water at 20 ° C. is preferably 2% by mass or more, more preferably 5% by mass or more.
The phthalocyanine dye used in the present invention preferably has a water solubility of 2% by mass or more at 20 ° C.

In addition, water-soluble dyes such as direct dyes, acid dyes, food dyes, basic dyes, and reactive dyes can be used in combination. Among them, preferred is
CI Direct Red 2, 4, 9, 23, 26, 31, 39, 62, 63, 72, 75, 76, 79, 80, 81, 83, 84, 89, 92, 95, 111, 173, 184, 207 , 211, 212, 214, 218, 21, 223, 224, 225, 226, 227, 232, 233, 240, 241, 242, 243, 247
CI Direct Violet 7, 9, 47, 48, 51, 66, 90, 93, 94, 95, 98, 100, 101
CI Direct Yellow 8, 9, 11, 12, 27, 28, 29, 33, 35, 39, 41, 44, 50, 53, 58, 59, 68, 86, 87, 93, 95, 96, 98, 100 , 106, 108, 109, 110, 130, 132, 142, 144, 161, 163
CI Direct Blue 1, 10, 15, 22, 25, 55, 67, 68, 71, 76, 77, 78, 80, 84, 86, 87, 90, 98, 106, 108, 109, 151, 156, 158 , 159, 160, 168, 189, 192, 193, 194, 199, 200, 201, 202, 203, 207, 211, 213, 214, 218, 225, 229, 236, 237, 244, 248, 249, 251 252 264 270 280 288 289 291
CI Direct Black 9, 17, 19, 22, 32, 51, 56, 62, 69, 77, 80, 91, 94, 97, 108, 112, 113, 114, 117, 118, 121, 122, 125, 132 , 146, 154, 166, 168, 173, 199
CI Acid Red 35, 42, 52, 57, 62, 80, 82, 111, 114, 118, 119, 127, 128, 131, 143, 151, 154, 158, 249, 254, 257, 261, 263, 266 , 289, 299, 301, 305, 336, 337, 361, 396, 397
CI Acid Violet 5, 34, 43, 47, 48, 90, 103, 126
CI Acid Yellow 17, 19, 23, 25, 39, 40, 42, 44, 49, 50, 61, 64, 76, 79, 110, 127, 135, 143, 151, 159, 169, 174, 190, 195 , 196, 197, 199, 218, 219, 222, 227
CI Acid Blue 9, 25, 40, 41, 62, 72, 76, 78, 80, 82, 92, 106, 112, 113, 120, 127: 1, 129, 138, 143, 175, 181, 205, 207 220, 221, 230, 232, 247, 258, 260, 264, 271, 277, 278, 279, 280, 288, 290, 326
CI Acid Black 7, 24, 29, 48, 52: 1, 172
CI Reactive Red 3, 13, 17, 19, 21, 22, 23, 24, 29, 35, 37, 40, 41, 43, 45, 49, 55
CI Reactive Violet 1, 3, 4, 5, 6, 7, 8, 9, 16, 17, 22, 23, 24, 26, 27, 33, 34
CI Reactive Yellow 2, 3, 13, 14, 15, 17, 18, 23, 24, 25, 26, 27, 29, 35, 37, 41, 42
CI Reactive Blue 2, 3, 5, 8, 10, 13, 14, 15, 17, 18, 19, 21, 25, 26, 27, 28, 29, 38
CI Reactive Black 4, 5, 8, 14, 21, 23, 26, 31, 32, 34
CI Basic Red 12, 13, 14, 15, 18, 22, 23, 24, 25, 27, 29, 35, 36, 38, 39, 45, 46
CI Basic Violet 1, 2, 3, 7, 10, 15, 16, 20, 21, 25, 27, 28, 35, 37, 39, 40, 48
CI Basic Yellow 1, 2, 4, 11, 13, 14, 15, 19, 21, 23, 24, 25, 28, 29, 32, 36, 39, 40
CI Basic Blue 1, 3, 5, 7, 9, 22, 26, 41, 45, 46, 47, 54, 57, 60, 62, 65, 66, 69, 71
CI Basic Black 8, etc.

  Furthermore, a pigment can be used in combination. As the pigment that can be used in the ink of the present invention, commercially available pigments and known pigments described in various documents can be used. Regarding the literature, the Color Index (Edited by The Society of Dyers and Colorists), "Revised New Edition Pigment Handbook" edited by Japan Pigment Technology Association (1989), "Latest Pigment Applied Technology" CMC Publishing (1986), "Printing Ink Technology" CMC Publication (1984), Industrial Organic Pigments by V. Herbst and K. Hunger (VCH Verlagsgesellschaft, 1993). Specifically, for organic pigments, azo pigments (azo lake pigments, insoluble azo pigments, condensed azo pigments, chelate azo pigments), polycyclic pigments (phthalocyanine pigments, anthraquinone pigments, perylene and perinone pigments, indigo pigments, quinacridone Pigments, dioxazine pigments, isoindolinone pigments, quinophthalone pigments, diketopyrrolopyrrole pigments, dyed lake pigments (acid or basic dye lake pigments), azine pigments, etc. CI Pigment Yellow 34, 37, 42, 53 for yellow pigments, CI Pigment Red 101, 108 for red pigments, CI Pigment Blue 27, 29, 17: 1 for blue pigments, CI Pigment Black for black pigments 7, white pigment CI Pigment White 4,6,18,21 and the like.

  As a pigment having a preferable color tone for image formation, a phthalocyanine pigment, an anthraquinone-based indanthrone pigment (for example, CI Pigment Blue 60), a dyed lake pigment-based triarylcarbonium pigment are preferable for blue to cyan pigments, and in particular phthalocyanine. Pigments (preferred examples include copper phthalocyanine such as CI Pigment Blue 15: 1, 15: 2, 15: 3, 15: 4, and 15: 6, monochloro or low chlorinated copper phthalocyanine, and arnium phthalocyanine. Pigment described in European Patent No. 860475, metal-free phthalocyanine which is CI Pigment Blue 16, phthalocyanine whose central metal is Zn, Ni, Ti, etc., among which CI Pigment Blue 15: 3, 15: 4, aluminum phthalocyanine ) Is most preferred.

  For red to violet pigments, azo pigments (preferred examples include CI Pigment Red 3, 5, 11, 22, 38, 48: 1, 48: 2, 48: 3, 48: 3, 48: 3, 48: 3). 4, 49: 1, 52: 1, 53: 1, 57: 1, 63: 2, 144, 146, 184), etc. 146, 184), quinacridone pigments (preferred examples include CI Pigment Red 122, 192, 202, 207, 209, CI Pigment Violet 19, 42, and among them, CI Pigment Red 122). Dye-attached lake pigment triarylcarbonium pigments (preferred examples include xanthene CI Pigment Red 81: 1, CI Pigment Violet 1, 2, 3, 27, 39), dioxazine pigments (for example, CI Pigment Violet 23, 37), diketopyrrolopyrrole pigment (eg CI Pigment Red 254), perylene pigment (eg CI Pigment Violet 29), anthraquinone Fee (e.g., C. I. Pigment Violet 5: 1, the 31, the 33), thioindigo (e.g. C. I. Pigment Red 38, the 88) is preferably used.

  As yellow pigments, azo pigments (preferred examples include monoazo pigment-based CI Pigment Yellow 1, 3, 74, 98, disazo pigment-based CI Pigment Yellow 12, 13, 14, 16, 17, 83, CI Pigment Yellow 93, 94, 95, 128, 155, benzimidazolone-based CI Pigment Yellow 120, 151, 154, 156, 180, etc., among which preferable ones do not use benzidine-based compounds), iso Indoline / isoindolinone pigments (preferred examples include CI Pigment Yellow 109, 110, 137, 139), quinophthalone pigments (preferred examples include CI Pigment Yellow 138), and furapantron pigments (for example, CI Pigment Yellow 24) Is preferably used.

Preferred examples of the black pigment include inorganic pigments (preferably carbon black and magnetite as examples) and aniline black.
In addition, an orange pigment (CI Pigment Orange 13, 16, etc.) or a green pigment (CIPigment Green 7, etc.) may be used.

The pigment that can be used in the ink of the present invention may be the above-mentioned bare pigment or a surface-treated pigment. Surface treatment methods include resin or wax surface coating, surfactant deposition, reactive substances (eg radicals derived from silane coupling agents, epoxy compounds, polyisocyanates, diazonium salts, etc.) pigments A method of bonding to the surface is conceivable and is described in the following documents and patents.
(1) Properties and applications of metal soap (Sachishobo)
(2) Printing ink printing (CMC Publishing 1984)
(3) Latest pigment application technology (CMC Publishing 1986)
(4) US Pat. Nos. 5,554,739 and 5,571,311 (5) Japanese Patent Application Laid-Open Nos. 9-151342, 10-140065, 10-292143, and 11-166145 The self-dispersing pigment prepared by allowing the diazonium salt to act on carbon black and the encapsulated pigment prepared by the method described in the Japanese patent (5) above use an extra dispersant in the ink. This is particularly effective because dispersion stability can be obtained without any problems.

In the ink of the present invention, the pigment may be further dispersed using a dispersant. Various known dispersants can be used in accordance with the pigment to be used, for example, a surfactant-type low-molecular dispersant or a polymer-type dispersant. Examples of the dispersant include those described in JP-A-3-69949, European Patent 549486 and the like. In addition, when a dispersant is used, a pigment derivative called a synergist may be added to promote adsorption of the dispersant to the pigment.
The particle size of the pigment that can be used in the ink of the present invention is preferably in the range of 0.01 to 10 μm after dispersion, and more preferably 0.05 to 1 μm.
As a method for dispersing the pigment, a known dispersion technique used in ink production or toner production can be used. Examples of the dispersing machine include vertical or horizontal agitator mills, attritors, colloid mills, ball mills, three roll mills, pearl mills, super mills, impellers, dispersers, KD mills, dynatrons, and pressure kneaders. Details are described in "Latest Pigment Application Technology" (CMC Publishing, 1986).

Next, the surfactant that can be contained in the ink jet recording ink of the present invention will be described.
By incorporating a surfactant into the ink jet recording ink of the present invention and adjusting the liquid physical properties of the ink, the ink ejection stability is improved, the water resistance of the image is improved, and bleeding of the printed ink is prevented. It can have an excellent effect.
Examples of the surfactant include anionic surfactants such as sodium dodecyl sulfate, sodium dodecyloxysulfonate, sodium alkylbenzenesulfonate, and cationic surfactants such as cetylpyridinium chloride, trimethylcetylammonium chloride, and terabutylammonium chloride. And nonionic surfactants such as polyoxyethylene nonylphenyl ether, polyoxyethylene naphthyl ether, polyoxyethylene octylphenyl ether, and the like. Among these, nonionic surfactants are particularly preferably used.

  The content of the surfactant is 0.001 to 15% by mass, preferably 0.005 to 10% by mass, and more preferably 0.01 to 5% by mass with respect to the ink.

  The ink for inkjet recording of the present invention can be prepared by dissolving or dispersing the phthalocyanine dye and preferably a surfactant in an aqueous medium. The “aqueous medium” in the present invention means a mixture of water or a mixture of water and a small amount of a water-miscible organic solvent with additives such as a wetting agent, a stabilizer and a preservative added as necessary.

When preparing the ink liquid of the present invention, in the case of water-soluble ink, it is preferable to first dissolve in water. Thereafter, various solvents and additives are added, dissolved and mixed to obtain a uniform ink solution.
As the dissolution method at this time, various methods such as dissolution by stirring, dissolution by ultrasonic irradiation, and dissolution by shaking can be used. Of these, the stirring method is particularly preferably used. In the case of stirring, various methods such as fluidized stirring known in the art and stirring using shearing force using an inverted agitator or dissolver can be used. On the other hand, a stirring method using a shearing force with the bottom surface of the container, such as a magnetic stirrer, can be preferably used.

  Examples of water miscible organic solvents that can be used in the present invention include alcohols (eg, methanol, ethanol, propanol, isopropanol, butanol, isobutanol, sec-butanol, t-butanol, pentanol, hexanol, cyclohexanol, Benzyl alcohol), polyhydric alcohols (eg, ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, polypropylene glycol, butylene glycol, hexanediol, pentanediol, glycerin, hexanetriol, thiodiglycol ), Glycol derivatives (eg, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, Tylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monobutyl ether, dipropylene glycol monomethyl ether, triethylene glycol monomethyl ether, ethylene glycol diacetate, ethylene glycol monomethyl ether acetate, Triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, ethylene glycol monophenyl ether), amine (eg, ethanolamine, diethanolamine, triethanolamine, N-methyldiethanolamine, N-ethyldiethanolamine, morpholine, N-ethylmorpholine, ethylene Amin, diethylenetriamine, triethylenetetramine, polyethyleneimine, tetramethylpropylenediamine) and other polar solvents (eg, formamide, N, N-dimethylformamide, N, N-dimethylacetamide, dimethylsulfoxide, sulfolane, 2-pyrrolidone, N -Methyl-2-pyrrolidone, N-vinyl-2-pyrrolidone, 2-oxazolidone, 1,3-dimethyl-2-imidazolidinone, acetonitrile, acetone) and the like. Two or more kinds of the water-miscible organic solvents may be used in combination.

When the phthalocyanine dye is an oil-soluble dye, it can be prepared by dissolving the oil-soluble dye in a high-boiling organic solvent and emulsifying and dispersing it in an aqueous medium.
The boiling point of the high-boiling organic solvent used in the present invention is preferably 150 ° C. or higher, more preferably 170 ° C. or higher.
Examples of the high boiling point organic solvent include phthalate esters (for example, dibutyl phthalate, dioctyl phthalate, dicyclohexyl phthalate, di-2-ethylhexyl phthalate, decyl phthalate, bis (2,4-di-tert-amylphenyl). Isophthalate, bis (1,1-diethylpropyl) phthalate), esters of phosphoric acid or phosphone (eg diphenyl phosphate, triphenyl phosphate, tricresyl phosphate, 2-ethylhexyl diphenyl phosphate, dioctyl butyl phosphate, tricyclohexyl phosphate) , Tri-2-ethylhexyl phosphate, tridodecyl phosphate, di-2-ethylhexyl phenyl phosphate), benzoic acid ester (for example, 2-ethylhexyl Benzoate, 2,4-dichloro benzoate, dodecyl benzoate, 2-ethylhexyl -p- hydroxybenzoate),

Amides (eg, N, N-diethyldodecanamide, N, N-diethyllaurylamide), alcohols or phenols (isostearyl alcohol, 2,4-di-tert-amylphenol, etc.), aliphatic esters ( For example, dibutoxyethyl succinate, di-2-ethylhexyl succinate, 2-hexyldecyl tetradecanoate, tributyl citrate, diethyl azelate, isostearyl lactate, trioctyl citrate), aniline derivatives (N, N-dibutyl- 2-butoxy-5-tert-octylaniline, etc.), chlorinated paraffins (paraffins having a chlorine content of 10% to 80%), trimesic acid esters (for example, tributyl trimesate), dodecylbenzene, diisopropylnaphthalene, phenol Class (for example 2,4-di-tert-amylphenol, 4-dodecyloxyphenol, 4-dodecyloxycarbonylphenol, 4- (4-dodecyloxyphenylsulfonyl) phenol), carboxylic acids (for example, 2- (2,4- Examples thereof include di-tert-amylphenoxybutyric acid, 2-ethoxyoctanedecanoic acid) and alkylphosphoric acids (for example, di-2 (ethylhexyl) phosphoric acid, diphenylphosphoric acid).
The high boiling point organic solvent can be used in an amount of 0.01 to 3 times, preferably 0.01 to 1.0 times the mass ratio of the oil-soluble dye.
These high-boiling organic solvents may be used alone or in a mixture of several types (eg tricresyl phosphate and dibutyl phthalate, trioctyl phosphate and di (2-ethylhexyl) sebacate, dibutyl phthalate and poly (Nt-butyl). Acrylamide)].

  Examples of other high boiling point organic solvents used in the present invention and methods for synthesizing these high boiling point organic solvents include, for example, U.S. Pat.Nos. 2,322,027, 2,533,514, 2,772,163, 2,835,579, and 3,594,171, 3,676,137, 3,689,271, 3,700,454, 3,748,141, 3,764,336, 3,765,897, 3,912,515, 3,936,303, 4,004,928, No. 4,080,209, No. 4,127,413, No. 4,193,802, No. 4,207,393, No. 4,220,711, No. 4,239,851, No. 4,278,757, No. 4,353,979, No. 4,363,873, No. 4,430,421, No. 4,430,422, 4,464,464, 4,483,918, 4,540,657, 4,684,606, 4,728,599, 4,745,049, 4,935,321, 5,013,639, European Patent 276,319A, 286,253A, 289,820A, 309,158A, 309,159A, 309,160A, 509,311A No. 510,576A, East German Patent No. 147,009, No. 157,147, No. 159,573, No. 225,240A, British Patent No. 2,091,124A, JP-A-48-47335, No. 50-26530, 51-25133, 51-26036, 51-27921, 51-27922, 51-149028, 52-46816, 53-1520, 53-1521, 53-1521, 53- 15127, 53-146622, 54-91325, 54-106228, 54-118246, 55-59464, 56-64333, 56-81836, 59-204041 No. 61-84641, No. 62-118345, No. 62-247364, No. 63-167357, No. 63-214744, No. 63-301941, No. 64-9452, No. 64-9454 64-68745, JP 1-101543, 1-102454, 2-792, 2-4239, 2-43541, 4-29237, 4-30165, 4 -232946, 4-346338, etc.

  In the present invention, the oil-soluble dye and the high boiling point organic solvent are emulsified and dispersed in an aqueous medium. In the emulsification dispersion, a low boiling point organic solvent may be used in combination in some cases from the viewpoint of emulsification. The low-boiling organic solvent that can be used in combination is an organic solvent having a boiling point of about 30 ° C. or higher and 150 ° C. or lower at normal pressure. For example, esters (eg ethyl acetate, butyl acetate, ethyl propionate, β-ethoxyethyl acetate, methyl cellosolve acetate), alcohols (eg isopropyl alcohol, n-butyl alcohol, secondary butyl alcohol), ketones (eg methyl isobutyl) Ketone, methyl ethyl ketone, cyclohexanone), amides (for example, dimethylformamide, N-methylpyrrolidone), ethers (for example, tetrahydrofuran, dioxane) and the like are preferably used, but are not limited thereto.

The emulsification dispersion is carried out in order to disperse an oil phase in which a dye is dissolved in a mixed solvent of a high-boiling organic solvent and, optionally, a low-boiling organic solvent, in an aqueous phase mainly composed of water to form fine oil droplets in the oil phase. Is called. At this time, additives such as a surfactant, a wetting agent, a dye stabilizer, an emulsion stabilizer, an antiseptic agent, and an antifungal agent, which will be described later, are added to either or both of the aqueous phase and the oil phase as necessary. be able to.
As an emulsification method, a method of adding an oil phase to an aqueous phase is common, but a so-called phase inversion emulsification method in which an aqueous phase is dropped into an oil phase can also be preferably used.

In the emulsification dispersion of the present invention, various surfactants can be used. Anionic interfaces such as fatty acid salts, alkyl sulfate esters, alkyl benzene sulfonates, alkyl naphthalene sulfonates, dialkyl sulfosuccinates, alkyl phosphate esters, naphthalene sulfonate formalin condensates, polyoxyethylene alkyl sulfates, etc. Activator, polyoxyethylene alkyl ether, polyoxyethylene alkyl allyl ether, polyoxyethylene fatty acid ester, sorbitan fatty acid ester, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene alkylamine, glycerin fatty acid ester, oxyethyleneoxypropylene block copolymer Nonionic surfactants such as Further, SURFYNOLS (Air Products & Chemicals), which is an acetylene-based polyoxyethylene oxide surfactant, is also preferably used. An amine oxide type amphoteric surfactant such as N, N-dimethyl-N-alkylamine oxide is also preferred. Further, pages (37) to (38) of JP-A-59-157,636, Research Disclosure No. The surfactants described in 308119 (1989) can also be used.
The surfactant used for emulsification has the same purpose as the surfactant added to adjust the liquid physical properties of the ink for ink jet recording described above, but the same type can be used as a result. It can also serve to adjust the physical properties of the ink.

For the purpose of stabilization immediately after emulsification, a water-soluble polymer can be added in combination with the surfactant. As the water-soluble polymer, polyvinyl alcohol, polyvinyl pyrrolidone, polyethylene oxide, polyacrylic acid, polyacrylamide or a copolymer thereof is preferably used. It is also preferable to use natural water-soluble polymers such as polysaccharides, casein, and gelatin.
Further, for stabilization of the dye dispersion, acrylic acid esters, methacrylic acid esters, vinyl esters, acrylamides, methacrylamides, olefins, styrenes, vinyl ethers that are not substantially soluble in an aqueous medium, Polyvinyl, polyurethane, polyester, polyamide, polyurea, polycarbonate and the like obtained by polymerization of acrylonitrile can also be used in combination. These polymers preferably contain —SO ₃ ⁻ and —COO ⁻ . When these polymers that do not substantially dissolve in an aqueous medium are used in combination, it is preferably used in an amount of 20% by mass or less, more preferably 10% by mass or less of the high boiling point organic solvent.

When an oil-soluble dye or a high-boiling organic solvent is dispersed by emulsification to obtain a water-based ink, the control of the particle size is particularly important. In order to increase color purity and density when an image is formed by inkjet, it is essential to reduce the average particle size. The volume average particle size is preferably 1 μm or less, more preferably 5 to 100 nm.
In addition to static light scattering, dynamic light scattering, and centrifugal sedimentation, the methods for measuring the volume average particle size and particle size distribution of the dispersed particles are described in pages 417 to 418 of Experimental Chemistry Course 4th edition. It can be easily measured by a known method such as using a method.
For example, after dilution with distilled water so that the particle concentration in the ink is 0.1 to 1% by mass, it is easy with a commercially available volume average particle size measuring device (for example, Microtrac UPA (manufactured by Nikkiso Co., Ltd.)). Can be measured. Furthermore, the dynamic light scattering method using the laser Doppler effect is particularly preferable because it can measure the particle size up to a small size.
The volume average particle diameter is an average particle diameter weighted by the particle volume, and is the sum of the diameter of each particle multiplied by the volume of the particle divided by the total volume of the particles. The volume average particle size is described in “Polymer Latex Chemistry” (by Soichi Muroi, Polymer Press Society), page 119.

It was also found that the presence of coarse particles also plays a very important role in printing performance. That is, it has been found that the coarse particles clog the nozzles of the head, or even if they are not clogged, the ink is not ejected or the ink is not ejected, resulting in a serious influence on the printing performance. In order to prevent this, it is important to limit the number of particles of 5 μm or more to 10 or less and 1 μm or more to 1000 or less in 1 μL of ink when the ink is used.
As a method for removing these coarse particles, a known centrifugal separation method, microfiltration method, or the like can be used. These separation means may be performed immediately after the emulsification dispersion, or may be performed immediately after filling the ink dispersion with various additives such as a wetting agent and a surfactant.
A mechanical emulsifier can be used as an effective means for reducing the average particle size and eliminating coarse particles.

As the emulsifying device, known devices such as a simple stirrer, impeller stirring method, in-line stirring method, mill method such as colloid mill, and ultrasonic method can be used, but the use of a high-pressure homogenizer is particularly preferable.
The detailed mechanism of the high-pressure homogenizer is described in U.S. Pat. No. 4,533,254, JP-A-6-47264, and the like, but as a commercially available apparatus, a Gorin homogenizer (APV GAULIN INC.), Micro There are a fluidizer (MICROFLUIDEX INC.), An optimizer (Sugino Machine Co., Ltd.) and the like.
In addition, a high-pressure homogenizer equipped with a mechanism for atomizing in an ultrahigh-pressure jet stream as described in US Pat. No. 5,720,551 in recent years is particularly effective for the emulsification dispersion of the present invention. DeBEE2000 (BEE INTERNIONAL LTD.) Is an example of an emulsifying apparatus using this ultra-high pressure jet stream.

The pressure when emulsifying with the high-pressure emulsifying dispersion device is 50 MPa or more, preferably 60 MPa or more, more preferably 180 MPa or more.
For example, it is a particularly preferable method that two or more types of emulsifiers are used in combination by a method such as emulsification with a stirring emulsifier and then passing through a high-pressure homogenizer. Also preferred is a method of once emulsifying and dispersing with these emulsifiers, adding an additive such as a wetting agent or a surfactant, and then passing the high-pressure homogenizer again while filling the cartridge with ink.
When a low boiling point organic solvent is contained in addition to the high boiling point organic solvent, it is preferable to remove the low boiling point solvent from the viewpoint of the stability of the emulsion and safety and health. Various known methods can be used as the method for removing the low boiling point solvent depending on the type of the solvent. That is, an evaporation method, a vacuum evaporation method, an ultrafiltration method, and the like. This step of removing the low-boiling organic solvent is preferably performed as soon as possible immediately after emulsification.

  The ink for ink jet recording obtained in the present invention includes a drying inhibitor for preventing clogging due to dry operation at the ink jetting port, a penetration accelerator for allowing the ink to penetrate better into the paper, an ultraviolet absorber, Select and use appropriate amounts of additives such as antioxidants, viscosity modifiers, surface tension modifiers, dispersants, dispersion stabilizers, antifungal agents, rust inhibitors, pH adjusters, antifoaming agents, chelating agents, etc. be able to.

  The drying inhibitor used in the present invention is preferably a water-soluble organic solvent having a vapor pressure lower than that of water. Specific examples include ethylene glycol, propylene glycol, diethylene glycol, polyethylene glycol, thiodiglycol, dithiodiglycol, 2-methyl-1,3-propanediol, 1,2,6-hexanetriol, acetylene glycol derivatives, glycerin. Polyhydric alcohols typified by trimethylolpropane, etc., lower alkyl ethers of polyhydric alcohols such as ethylene glycol monomethyl (or ethyl) ether, diethylene glycol monomethyl (or ethyl) ether, triethylene glycol monoethyl (or butyl) ether , Heterocyclic compounds such as 2-pyrrolidone, N-methyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, N-ethylmorpholine, sulfolane, dimethylsulfoxy , Sulfur-containing compounds such as 3-sulfolene, diacetone alcohol, polyfunctional compounds such as diethanolamine, and urea derivatives. Of these, polyhydric alcohols such as glycerin and diethylene glycol are more preferred. Moreover, said drying inhibitor may be used independently and may be used together 2 or more types. These drying inhibitors are preferably contained in the ink in an amount of 10 to 50% by mass.

  Examples of penetration enhancers used in the present invention include alcohols such as ethanol, isopropanol, butanol, di (tri) ethylene glycol monobutyl ether, 1,2-hexanediol, sodium lauryl sulfate, sodium oleate, and nonionic surfactants. Etc. can be used. If these are contained in the ink in an amount of 10 to 30% by mass, the effect is sufficient, and it is preferable to use them in a range of addition amounts that do not cause printing bleeding and paper loss (print through).

  Examples of the ultraviolet absorber used for improving the storability of the image in the present invention include JP-A Nos. 58-185677, 61-190537, JP-A-2-782, and JP-A-5-97075. Benzotriazole compounds described in JP-A-9-34057, etc., benzophenone compounds described in JP-A No. 46-2784, JP-A No. 5-194443, US Pat. No. 3,214,463, etc. 48-30492, 56-21114, and cinnamic acid compounds described in JP-A-10-88106, JP-A-4-298503, JP-A-8-53427, and 8-239368. And triazine compounds described in JP-A-10-182621, JP-A-8-501291, etc. Jar No. The compounds described in No. 24239, compounds that emit fluorescence by absorbing ultraviolet rays typified by stilbene-based compounds and benzoxazole-based compounds, so-called fluorescent brighteners, can also be used.

  In the present invention, various kinds of organic and metal complex anti-fading agents can be used as the antioxidant used to improve image storage stability. Organic anti-fading agents include hydroquinones, alkoxyphenols, dialkoxyphenols, phenols, anilines, amines, indanes, chromans, alkoxyanilines, heterocycles, etc. Complex, zinc complex and the like. More specifically, Research Disclosure No. No. 17643, Nos. VII to I, J; 15162, ibid. No. 18716, page 650, left column, ibid. No. 36544, page 527, ibid. No. 307105, page 872, ibid. The compounds described in the patent cited in US Pat. No. 15,162, or the compounds represented by the general formulas and compound examples of representative compounds described on pages 127 to 137 of JP-A-62-215272 can be used.

Antifungal agents used in the present invention include sodium dehydroacetate, sodium benzoate, sodium pyridinethione-1-oxide, p-hydroxybenzoic acid ethyl ester, 1,2-benzisothiazolin-3-one and salts thereof. Can be mentioned. These are preferably used in the ink in an amount of 0.02 to 5.00% by mass.
Details of these are described in “Encyclopedia of Antibacterial and Antifungal Agents” (edited by the Japanese Association of Antimicrobial and Antifungal Society).
Examples of the rust inhibitor include acidic sulfite, sodium thiosulfate, ammonium thioglycolate, diisopropyl ammonium nitrite, pentaerythritol tetranitrate, dicyclohexyl ammonium nitrite, and benzotriazole. These are preferably used in the ink in an amount of 0.02 to 5.00% by mass.

In the present invention, nonionic, cationic or anionic surfactants may be mentioned as surface tension adjusting agents in addition to the surfactants described above. For example, anionic surfactants include fatty acid salts, alkyl sulfate esters, alkyl benzene sulfonates, alkyl naphthalene sulfonates, dialkyl sulfosuccinates, alkyl phosphate esters, naphthalene sulfonate formalin condensates, polyoxyethylene alkyl sulfates. Examples of the nonionic surfactant include polyoxyethylene alkyl ether, polyoxyethylene alkyl allyl ether, polyoxyethylene fatty acid ester, sorbitan fatty acid ester, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene Examples thereof include alkylamines, glycerin fatty acid esters, and oxyethyleneoxypropylene block copolymers. SURFYNOLS (Air Products & Chemicals), which is an acetylene-based polyoxyethylene oxide surfactant, is also preferably used. An amine oxide type amphoteric surfactant such as N, N-dimethyl-N-alkylamine oxide is also preferred. Further, pages (37) to (38) of JP-A-59-157,636, Research Disclosure No. The surfactants described in 308119 (1989) can also be used.
The surface tension of the ink of the present invention is preferably 20 to 60 mN / m with or without these. Furthermore, 25-45 mN / m is preferable.

  The viscosity of the ink used in the present invention is preferably 30 mPa · s or less. Furthermore, since it is more preferable to adjust to 20 mPa * s or less, a viscosity modifier may be used in order to adjust a viscosity. Examples of the viscosity modifier include water-soluble polymers such as celluloses and polyvinyl alcohol, and nonionic surfactants. For more details, see Chapter 9 of “Viscosity Preparation Technology” (Technical Information Association, 1999), and “Chemicals for Inkjet Printers (98 Supplement)-Material Development Trends and Prospects Survey” (CMC, 1997) 162- Page 174.

  In the present invention, the above-mentioned cation, anion, and nonionic surfactants are used as a dispersant and a dispersion stabilizer, and fluorine-based, silicone-based compounds and chelating agents represented by EDTA are used as an antifoaming agent as necessary. Can be used.

The recording paper and recording film used in the image recording method of the present invention will be described. The support for recording paper and recording film consists of chemical pulp such as LBKP and NBKP, mechanical pulp such as GP, PGW, RMP, TMP, CTMP, CMPMP, and CGP, and waste paper pulp such as DIP. Additives such as known pigments, binders, sizing agents, fixing agents, cationic agents, paper strength enhancers, etc. can be mixed, and those manufactured in various devices such as long net paper machines and circular net paper machines can be used. It is. In addition to these supports, any of synthetic paper and plastic film sheets may be used, and the thickness of the support is preferably 10 to 250 μm and the basis weight is preferably 10 to 250 g / m ² .
An image receiving layer and a back coat layer may be provided on the support as they are to obtain an image receiving material, or after a size press or anchor coat layer is provided with starch, polyvinyl alcohol or the like, an image receiving layer and a back coat layer may be provided to form an image receiving material. Good. Further, the support may be flattened by a calendar device such as a machine calendar, a TG calendar, or a soft calendar.
In the present invention, as the support, paper and plastic film laminated on both sides with polyolefin (eg, polyethylene, polystyrene, polybutene and copolymers thereof) or polyethylene terephthalate are more preferably used. It is preferable to add a white pigment (eg, titanium oxide, zinc oxide) or a coloring dye (eg, cobalt blue, ultramarine blue, neodymium oxide) to the polyolefin.

  The image receiving layer provided on the support contains a porous material and an aqueous binder. The image receiving layer preferably contains a pigment, and the pigment is preferably a white pigment. White pigments include calcium carbonate, kaolin, talc, clay, diatomaceous earth, synthetic amorphous silica, aluminum silicate, magnesium silicate, calcium silicate, aluminum hydroxide, alumina, lithopone, zeolite, barium sulfate, calcium sulfate, titanium dioxide, Examples thereof include inorganic white pigments such as zinc sulfide and zinc carbonate, organic pigments such as styrene pigments, acrylic pigments, urea resins and melamine resins. A porous white inorganic pigment is particularly preferable, and synthetic amorphous silica having a large pore area is particularly preferable. As the synthetic amorphous silica, either anhydrous silicic acid obtained by a dry production method (gas phase method) or hydrous silicic acid obtained by a wet production method can be used.

  Specific examples of the recording paper containing the pigment in the image receiving layer include JP-A Nos. 10-81064, 10-119423, 10-157277, 10-217601, and 10-348409. No. 2001-138621, 2000-43401, 2000-2111235, 2000-309157, 2001-96897, 2001-138627, JP-A-11-91242, 8-2087, Those disclosed in Nos. 8-2090, 8-2091, 8-2093, 8-174992, 11-192777, and JP-A-2001-301314 can be used.

  The aqueous binder contained in the image receiving layer includes water-soluble polyvinyl alcohol, silanol-modified polyvinyl alcohol, starch, cationized starch, casein, gelatin, carboxymethylcellulose, hydroxyethylcellulose, polyvinylpyrrolidone, polyalkylene oxide, polyalkylene oxide derivatives, etc. Examples thereof include water-dispersible polymers such as polymers, styrene butadiene latexes, and acrylic emulsions. These aqueous binders can be used alone or in combination of two or more. In the present invention, among these, polyvinyl alcohol and silanol-modified polyvinyl alcohol are particularly preferable in terms of adhesion to pigments and peel resistance of the image receiving layer.

  The image receiving layer can contain a mordant, a water resistance agent, a light resistance improver, a gas resistance improver, a surfactant, a hardener and other additives in addition to the pigment and the aqueous binder.

The mordant added to the image receiving layer is preferably immobilized. For that purpose, a polymer mordant is preferably used.
For the polymer mordant, JP-A-48-28325, 54-74430, 54-124726, 55-22766, 55-142339, 60-23850, 60-23835, 60-23852, 60-23853, 60-57836, 60-60643, 60-118834, 60-122940, 60-122941, 60-122942, 60- No. 235134, JP-A-1-161236, U.S. Pat.Nos. 2,484,430, 2,548,564, 3,148,061, 3,309,690, 4,115,124, 4,124,386, 4,193,800, 4,273,853, 4,282,305, It is described in each specification of the same No. 4450224. An image receiving material containing a polymer mordant described in JP-A-1-161236, pages 212 to 215 is particularly preferred. When the polymer mordant described in the publication is used, an image with excellent image quality is obtained and the light resistance of the image is improved.

  The water-proofing agent is effective for making the image water-resistant. As these water-proofing agents, cationic resins are particularly desirable. Examples of such a cationic resin include polyamide polyamine epichlorohydrin, polyethyleneimine, polyamine sulfone, dimethyldiallylammonium chloride polymer, and cationic polyacrylamide. The content of these cationic resins is preferably 1 to 15% by mass, particularly 3 to 10% by mass, based on the total solid content of the image receiving layer.

Examples of the light resistance improver and gas resistance improver include phenol compounds, hindered phenol compounds, thioether compounds, thiourea compounds, thiocyanate compounds, amine compounds, hindered amine compounds, TEMPO compounds, hydrazine compounds, hydrazide compounds, amidine compounds, Vinyl group-containing compounds, ester compounds, amide compounds, ether compounds, alcohol compounds, sulfinic acid compounds, saccharides, water-soluble reducing compounds, organic acids, inorganic acids, hydroxy group-containing organic acids, benzotriazole compounds, benzophenone compounds, triazine compounds , Heterocyclic compounds, water-soluble metal salts, organometallic compounds, metal complexes, and the like.
Specific examples of these compounds include JP-A-10-182621, JP-A-2001-260519, JP-A-2000-260519, JP-B-4-34953, JP-B-4-34513, and JP-B-4-34512. , JP-A-11-170686, JP-A-60-67190, JP-A-7-276808, JP-A-2000-94829, JP-T 8-512258, JP-A-11-321090, etc. Is mentioned.

The surfactant functions as a coating aid, a peelability improver, a slippage improver or an antistatic agent. The surfactant is described in JP-A Nos. 62-173463 and 62-183457.
An organic fluoro compound may be used in place of the surfactant. The organic fluoro compound is preferably hydrophobic. Examples of the organic fluoro compound include a fluorine-based surfactant, an oily fluorine-based compound (eg, fluorine oil), and a solid fluorine compound resin (eg, tetrafluoroethylene resin). The organic fluoro compounds are described in JP-B-57-9053 (columns 8 to 17), JP-A-61-20994, and 62-135826.

  As the hardener, materials described in JP-A-1-161236, page 222, JP-A-9-263036, JP-A-10-119423, and JP-A-2001-310547 can be used.

  Examples of other additives added to the image receiving layer include pigment dispersants, thickeners, antifoaming agents, dyes, fluorescent whitening agents, preservatives, pH adjusters, matting agents, and hardening agents. The image receiving layer may be one layer or two layers.

The recording paper and the recording film can be provided with a back coat layer, and examples of components that can be added to this layer include a white pigment, an aqueous binder, and other components.
Examples of white pigments contained in the backcoat layer include light calcium carbonate, heavy calcium carbonate, kaolin, talc, calcium sulfate, barium sulfate, titanium dioxide, zinc oxide, zinc sulfide, zinc carbonate, satin white, and aluminum silicate. , Diatomaceous earth, calcium silicate, magnesium silicate, synthetic amorphous silica, colloidal silica, colloidal alumina, pseudoboehmite, aluminum hydroxide, alumina, lithopone, zeolite, hydrous halloysite, magnesium carbonate, magnesium hydroxide, white inorganic pigment, styrene And organic pigments such as polyethylene plastic pigments, acrylic plastic pigments, polyethylene, microcapsules, urea resins, and melamine resins.

  As the aqueous binder contained in the backcoat layer, styrene / maleate copolymer, styrene / acrylate copolymer, polyvinyl alcohol, silanol modified polyvinyl alcohol, starch, cationized starch, casein, gelatin, carboxymethylcellulose Water-soluble polymers such as hydroxyethyl cellulose and polyvinyl pyrrolidone, water-dispersible polymers such as styrene butadiene latex and acrylic emulsion, and the like. Examples of other components contained in the backcoat layer include an antifoaming agent, an antifoaming agent, a dye, a fluorescent brightening agent, a preservative, and a water-proofing agent.

  A polymer fine particle dispersion may be added to the constituent layers (including the back layer) of the inkjet recording paper and recording film. The polymer fine particle dispersion is used for the purpose of improving film properties such as dimensional stabilization, curling prevention, adhesion prevention, and film cracking prevention. The polymer fine particle dispersion is described in JP-A Nos. 62-245258, 62-1316648, and 62-110066. When a polymer fine particle dispersion having a low glass transition temperature (40 ° C. or lower) is added to a layer containing a mordant, cracking and curling of the layer can be prevented. Further, even when a polymer fine particle dispersion having a high glass transition temperature is added to the back layer, curling can be prevented.

  The ink for inkjet recording used in the present invention can also be used for purposes other than inkjet recording. For example, it can be used for display image materials, image forming materials for interior decoration materials, and image forming materials for outdoor decoration materials.

  Display image materials include posters, wallpaper, small decorative items (such as figurines and dolls), commercial flyers, wrapping paper, wrapping materials, paper bags, plastic bags, packaging materials, signs, transportation (automobiles, buses, trains, etc.) ) Refers to various things such as images drawn and attached to the side, clothes with logos, and so on. When the dye of the present invention is used as a material for forming a display image, the image includes all patterns of dyes that can be recognized by humans, such as abstract designs, characters, and geometric patterns, in addition to images in a narrow sense.

  The interior decoration material refers to various items such as wallpaper, decorative accessories (such as figurines and dolls), lighting fixture members, furniture members, floor and ceiling design members. When the dye of the present invention is used as an image forming material, the image includes all patterns of dyes that can be recognized by humans such as abstract designs, characters, and geometric patterns in addition to images in a narrow sense.

  The outdoor decoration material refers to various materials such as wall materials, roofing materials, signboards, gardening materials, outdoor decoration accessories (such as figurines and dolls), and members of outdoor lighting equipment. When the dye of the present invention is used as an image forming material, the image includes not only images in a narrow sense but also all patterns of dyes that can be recognized by humans, such as abstract designs, characters, and geometric patterns.

  In the above applications, examples of media on which a pattern is formed include various materials such as paper, fiber, cloth (including non-woven fabric), plastic, metal, and ceramics. As the dyeing form, the dye can be fixed in the form of mordanting, printing, or a reactive dye having a reactive group introduced. Among these, it is preferable that the mordanting is performed.

  EXAMPLES Hereinafter, although an Example demonstrates this invention concretely, it is not limited to this.

(Ink liquid adjustment)
After adding deionized water to the following components to make 1 liter, the mixture was stirred and dissolved for 1 hour while heating at 30 to 40 ° C. Thereafter, the ink solution for light cyan was prepared by filtration under reduced pressure through a microfilter having an average pore diameter of 0.25 μm.

(Ink liquid component for light cyan)
-Solid content-
Cyan dye [Compound No. 154] 17.5 g / l
PROXEL XL2 [Zeneca Company] 5g / l
-Liquid component-
Diethylene glycol (DEG) 90g / l
Glycerin (GR) 50g / l
Triethylene glycol monobutyl ether (TGB) 70g / l
Triethanolamine 6.9g / l
Surfynol STG 10g / l

  Further, a cyan ink liquid was prepared by increasing the amount of the cyan dye [Compound No. 154] to 68 g / l according to the above formulation.

(Cyan ink component)
-Solid content-
Cyan dye [Compound No. 154] 68 g / l
PROXEL XL2 [Zeneca Company] 5g / l
-Liquid component-
Diethylene glycol (DEG) 90g / l
Glycerin (GR) 50g / l
Triethylene glycol monobutyl ether (TGB) 70g / l
Triethanolamine 6.9g / l
Surfynol STG 10g / l

These inks are loaded into a cyan / light cyan ink cartridge of an ink jet printer PM-950C manufactured by EPSON, and other color inks are inks of PM-950C, and an ink-jet paper manufactured by Fuji Photo Film Co., Ltd. is used as an image receiving sheet. On the photo glossy paper EX, a portrait image with the most noticeable unevenness and roughness was printed as an image.
In this example, the drive voltage waveform of the PM-950C piezo head was adjusted so that the droplet ejection volume was 10 pl and the average droplet ejection speed was a predetermined value at the same time.

The printed image was examined for unevenness and roughness (smoothness of appearance) by the following subjective evaluation. The results are shown in Table 12.
A: Nine or more of ten people do not feel unevenness or roughness B: Seven or more of ten people do not feel unevenness or roughness C: Five or more of ten people do not feel unevenness or roughness D: Among ten people 3 or more people do not feel unevenness or roughness E: All 10 people feel unevenness or roughness

  From Table 12, it can be seen that unevenness and roughness of the image increase as the average droplet ejection speed of the ink decreases.

It is a schematic block diagram of an inkjet printer. FIG. 6 is a diagram illustrating a state in which ink droplets are ejected by extension of a piezo element. It is a schematic diagram showing a means for measuring the average droplet ejection speed and droplet ejection volume of ink droplets. It is a figure which shows the image which image | photographed the ink drop with the CCD camera. It is a figure which shows the relationship between the size of an ink droplet, and landing position fluctuation. It is a figure which shows the relationship between the impact speed of an ink droplet, and landing position fluctuation.

Claims (3)

An average droplet ejection speed of 2 m / sec or more when ejecting an inkjet recording ink formed by dissolving or dispersing at least one dye represented by the following general formula (I) in an aqueous medium onto a recording material An inkjet image recording method characterized by the above.
Formula (I)

In the above general formula (I);
X ₁ , X ₂ , X ₃ and X ₄ are each independently —SO—Z, —SO ₂ —Z, —SO ₂ NR ₁ R ₂ , a sulfo group, —CONR ₁ R ₂ or —CO ₂ R. Represents ₁ .
Z is a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted group Represents a heterocyclic group. R ₁ and R ₂ are each independently a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted aralkyl group, substituted or unsubstituted It represents an unsubstituted aryl group or a substituted or unsubstituted heterocyclic group. When a plurality of Z are present, they may be the same or different.
Y ₁ , Y ₂ , Y ₃ and Y ₄ each independently represent a monovalent substituent.
In addition, when any _{one of} X _{1 to} X ₄ and Y _{1 to} Y ₄ is present, they may be the same or different.
a ₁ ~a ₄ and b ₁ ~b ₄ each represent a number of substituents X ₁ to X ₄ and _{Y 1 ~Y 4, a 1 ~a} 4 are each independently an integer of 0 to 4, All of them are not 0 at the same time, and b _{1 to} b ₄ are each independently an integer of 0 to 4.
M is a hydrogen atom, a metal atom or an oxide, hydroxide or halide thereof.   An inkjet image recording method for recording an image with a plurality of ink droplets having different droplet ejection volumes, wherein an average droplet ejection speed of an ink droplet having a small droplet ejection volume is greater than an average droplet ejection speed of an ink droplet having a large droplet ejection volume. The inkjet image recording method according to claim 1.   An inkjet image recording apparatus using the inkjet image recording method according to claim 1.

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