JP2002309133A - Method for improving fastening to ozone gas of colored image - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for improving the fastness to an ozone gas of a colored image, an ink composition giving a colored image or a colored material excellent in fastness, and an ink jet ink, etc. SOLUTION: This method uses a compound having an oxidation potential higher than 1.0 V (vs SCE), a maximum absorption wavelength in the range of from 500 nm to 580 nm, and a half-value width of 150 nm or lower. The compound is represented by formula (1): A-N=N-B (wherein A and B are each an optionally substituted aryl or 5- or 6-membered heterocyclic group).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for improving ozone gas fastness of a colored image having a good hue, an azo compound, a colored composition, and a colored image wherein the colored composition is selected from an ink composition and an ink jet ink. To improve the fastness of ozone gas.

[0002]

2. Description of the Related Art In recent years, as an image recording material, a material mainly for forming a color image has been mainly used. Specifically, an ink jet recording material, a thermal transfer recording material, and an electrophotographic recording material have been used. Materials, transfer-type silver halide photosensitive materials, printing inks, recording pens, and the like are actively used. A color filter is used to record and reproduce a color image in an image pickup device such as a CCD or a CMOS in a photographing device and in an LCD or a PDP in a display in a display. In these color image recording materials and color filters, so-called three primary color dyes of an additive color method or a subtractive color method are used to reproduce or record a full-color image. However, absorption characteristics capable of realizing a preferable color reproduction range. And a robust dye that can withstand various use conditions and environmental conditions is desired.

[0003] The ink jet recording method is rapidly spreading and developing due to its low material cost, high speed recording, low noise during recording, and easy color recording. is there. Ink jet recording methods include a continuous method in which droplets are continuously ejected and an on-demand method in which droplets are ejected in response to an image information signal. , A method in which bubbles are generated in ink by heat to discharge droplets, a method using ultrasonic waves, and a method in which droplets are sucked and discharged by electrostatic force. In addition, as ink for inkjet recording,
Water-based ink, oil-based ink, or solid (melt-type) ink is used.

[0004] The dyes used in such inks for ink jet recording have good solubility or dispersibility in solvents, high density recording is possible,
Good hue, light, heat, environmental active gas (N
Ox, ozone, and other oxidizing gases, as well as SOx, etc.), excellent in water and chemicals, excellent in fixability to image receiving materials, and resistant to bleeding,
It is required that the ink has excellent storage properties, has no toxicity, has high purity, and is available at low cost. However, it is extremely difficult to find a dye that meets these requirements at a high level.
In particular, there is a strong demand for a dye having a good magenta hue and being robust against light and active gases in the environment, especially oxidizing gases such as ozone.

[0005] In order to use a colored image in the above-mentioned applications, it is necessary that the compounds used have the following properties in common. That is, having favorable absorption characteristics in terms of color reproducibility, manufacturing conditions, image forming conditions, and fastness under the used environmental conditions, for example, light resistance, heat resistance, moisture resistance, resistance to oxidizing gases such as ozone, In addition, it has good resistance to chemicals such as sulfurous acid gas and a large molar extinction coefficient.

Hitherto, phenol, naphthol, aniline and the like have been widely used as coupling components for azo compounds. An azo dye having a good hue obtained by using these coupling components is disclosed in JP-A-11-20967.
No. 3, Japanese Patent No. 3,020,660, etc., are known, but have a problem that light fastness is poor.
To improve this, a dye having a good hue and improved light fastness has recently been disclosed in Japanese Patent Application No. 2000-220649. However, all of the dyes known in the above patents have extremely poor fastness to oxidizing gases such as ozone.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned conventional problems and achieve the following objects. That is, the present invention provides: 1) a compound having specific physical property values, having an absorption characteristic excellent in color reproducibility as a three primary color pigment, and
A new method for improving the fastness of ozone gas, which has sufficient fastness to heat, humidity, and active gas in the environment. 2) Printing such as ink-jet printing, which gives colored images and coloring materials excellent in hue and fastness. It is an object of the present invention to provide a method for improving the fastness to ozone gas using various coloring compositions such as inks for use.

[0008]

Means for Solving the Problems The present inventors have studied in detail various dyes aiming at dyes having a good hue and high fastness against light and ozone. It has been found that the above problem can be solved by a compound having an oxidation potential of, in particular, an azo compound, and the present invention has been completed.

The above object of the present invention is solved by the following means. That is, 1. A method for improving the fastness to ozone gas of a colored image using a compound having an oxidation potential higher than 1.0 V (vs. SCE) and having a maximum absorption wavelength between 500 nm and 580 nm and a half width of 150 nm or less.

[0010] 2. 2. The method for improving ozone gas fastness of a colored image according to item 1, wherein the compound is an azo compound.

3. The azo compound has the following general formula (1)
3. The method for improving ozone gas fastness of a colored image according to the above item 2, wherein

[0012]

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In the formula, A and B each independently represent a substituted or unsubstituted aryl group or a substituted or unsubstituted 5- or 6-membered hetenyl group.

4. 4. The method for improving ozone gas fastness of a colored image according to any one of the above items 1 to 3, wherein a colored composition containing the compound is used.

[0015] 5. The coloring composition, an ink composition,
5. The method for improving ozone gas fastness of a colored image described in 4 above, wherein the method is selected from inkjet inks.

6. An ink-jet recording method comprising forming an image on an image-receiving material having an ink-receiving layer containing white inorganic pigment particles on a support using the ink-jet ink described in the above item 5.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. In this specification, “to” indicates a range including numerical values described before and after it as a minimum value and a maximum value, respectively.

In the method for improving the fastness to ozone gas of a colored image of the present invention, a compound having an oxidation potential nobler than 1.0 V (vs SCE) is used. The oxidation potential is preferably as high as possible, and the oxidation potential is more preferable than 1.1 V (vs. SCE).
Those which are more noble than CE) are most preferred.

The present inventors have studied the ozone gas fastness of the colored image. As a result, there is a correlation between the oxidation potential of the compound used for the colored image and the ozone gas fastness, and the value of the oxidation potential is higher than that of the saturated calomel electrode (SCE). On the other hand, it has been found that the use of a compound which is nobler than 1.0 V improves ozone gas fastness.

The reason why the ozone gas fastness of the colored image is improved can be explained by the relationship between the HOMO (highest occupied orbit) and the LUMO (lowest unoccupied orbit) between the compound and ozone gas. That is, it is considered that the reaction between the HOMO of the coloring compound and the LUMO of the ozone gas oxidizes the coloring compound, and as a result, the ozone gas fastness of the colored image is reduced. The HOMO of the compound may be lowered to lower the reactivity with ozone gas.

The value of Eox indicates the ease with which electrons move from the sample to the electrode, and the larger the value (the higher the oxidation potential), the more difficult it is for the electrons to move from the sample to the electrode. It represents that. In relation to the structure of the compound, the introduction of an electron-withdrawing group makes the oxidation potential more noble, and the introduction of an electron-donating group makes the oxidation potential lower.

The value of Eox, which will be described in detail below, means a potential at which a compound is an anode in voltammetry and electrons of the compound are extracted, and is considered to be approximately equal to the energy level of HOMO in the ground state of the compound. Have been.

The value of the oxidation potential (Eox) can be easily measured by those skilled in the art. Regarding this method, for example,
"New Instrumental" by Delahay
Methods in Electrochemist
ry ”(1954 Interscience Pu)
Blishers) and A. J. Bard et al., "El
electrochemical Methods ”(19
1980, John Wiley & Sons, Inc., Akira Fujishima et al., "Electrochemical Measurement Method" (1984, published by Gihodo Shuppan Co., Ltd.) and the like.

The measurement of the oxidation potential will be specifically described.
You. The oxidation potential is determined by sodium perchlorate or tetraperchlorate.
Dimethyl containing supporting electrolytes such as propyl ammonium
In a solvent such as chloroformate or acetonitrile.
1 × 10 test sample^-Four~ 1 × 10 ^-6Mol / l concentration
Dissolve so that cyclic voltammetry or
SCE as Reference Electrode Using DC Polarography
(Saturated calomel electrode). Also
The supporting electrolyte and solvent used depend on the oxidation potential and dissolution of the test sample.
An appropriate one can be selected depending on the sex. Can be used
For supporting electrolytes and solvents that can be used, see Akira Fujishima et al.
Science Measurement Method "(1984, published by Gihodo Shuppansha) 101-1
It is described on page 18.

The value of the oxidation potential may be deviated by several tens of mil volts due to the effect of the liquid potential difference or the liquid resistance of the sample solution, but is measured by calibrating using a standard sample (for example, hydroquinone). The reproducibility of the value of the set potential can be guaranteed.

The oxidation potential in the present invention is 0.1 mol
SCE (saturated calomel electrode) as a reference electrode in N, N-dimethylformamide containing dm ^-3 tetrapropylammonium perchlorate as a supporting electrolyte (compound concentration 1 × 10 ^-3 mol · dm ^-3 ) Using a graphite electrode as a working electrode and a platinum electrode as a counter electrode, values measured by DC polarography are used.

The oxidation potential also differs depending on the structure of the compound. Therefore, in order to reduce the reactivity with ozone, which is an electrophile, it is better to select a compound structure having an oxidation potential that is originally noble. Not only in terms of robustness,
Since an electron-withdrawing group or an electron-donating group can be arbitrarily introduced to adjust hue, physical properties, and the like, it can be said that it is more preferable from the viewpoint of molecular design.

For example, in order to reduce the reactivity with ozone as an electrophile, it is preferable to introduce an electron-withdrawing group at an arbitrary position in the structure of the compound to make the oxidation potential more noble. Therefore, when the Hammett's substituent constant σp value, which is a measure of the electron withdrawing or electron donating property of the substituent, is used, the oxidation potential can be made more noble by introducing a substituent having a large σp value.

The Hammett's substituent constant σp value will be described. Hammett's rule was used in 1935 to describe quantitatively 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. The substituent constants determined by the Hammett rule include a σp value and a σm value,
These values can be found in many common books, but are described, for example, in J. et al. A. Dean, "Lange's
Handbook of Chemistry "No. 12
Edition, 1979 (McGraw-Hill) and "Region of Chemistry" special edition, No. 122, pp. 96-103, 1979 (Nankodo).

The maximum absorption wavelength and the half width defined in the present invention can be easily measured by those skilled in the art.
Regarding the above measurement method, see, for example,
Edition Chemistry Lecture, 7 Spectroscopy II "(1992, published by Maruzen Co., Ltd.), pages 175 to 199. Specifically, a sample is dissolved in an appropriate solvent, and a quartz or glass cell is used. , Measured by a spectrophotometer using two cells, one for sample and one for control.
In addition to the solubility of the sample, it is required that the sample has no absorption in the measurement wavelength region, that the interaction with the solute molecule is small, and that the volatility is not so remarkable. Any solvent can be selected as long as it meets the above conditions.
In the present invention, N, N-dimethylformamide (D
The measurement is performed using MF) as a solvent.

Regarding the half width of the spectrum, see, for example, “The 4th Edition Experimental Chemistry Course 3 Basic Operation II” edited by The Chemical Society of Japan (1.
991 published by Maruzensha) page 154.
Specifically, it indicates the width of an absorption band that is の of the absorbance at the maximum absorption wavelength, and is used as a measure of the shape of the absorption spectrum. A spectrum having a small half width is a sharp spectrum, and a spectrum having a large half width is a broad spectrum. The presence of unnecessary absorption on the short-wave side and long-wave side does not have a favorable effect on color reproducibility. Therefore, in consideration of hue, a dye having a spectrum with a small half width is more preferable.

The maximum absorption wavelength and half width of the dye in the present invention are determined by preparing a solution having a concentration of about 5 × 10 ⁻⁵ mol · dm ^{−3 using} N, N-dimethylformamide as a solvent.
The value measured using a quartz cell having an optical path length of 1 cm is used.

In the present invention, the maximum absorption wavelength is 500 n
Compounds having a half width of 150 nm or less between m and 580 nm correspond to magenta dyes. As a magenta dye which gives a good hue, the maximum absorption wavelength is more preferably from 520 nm to 580 nm, even more preferably from 520 nm to 570 nm. Half width is 1
It is more preferably at most 10 nm, more preferably at most 90 nm.

Compounds having the above physical properties include azo dyes, quinone dyes, cyanine dyes, cationic dyes,
It can be arbitrarily selected from phthalocyanine dyes, indigo dyes, fulgide dyes, and intermolecular CT dyes.

In the present invention, any compound structure may be used, but an azo compound is particularly preferable because it has a rich color tone and satisfies the conditions of oxidation potential and hue, but is easy to synthesize. . In the following description, an azo compound will be described, but this description can be similarly applied to other dye structures, and the present invention is not limited to this.

In order to obtain a compound satisfying the conditions relating to the oxidation potential of the present invention, not only the oxidation potential is directly measured and confirmed by the above-mentioned method, but also a molecular design based on the structure of the compound is carried out. Can be obtained. The fact that the oxidation potential of a compound is related to the energy level of its HOMO is described in "Graduate School of Physical Chemistry (Medium)", edited by Manabu Senoo, et al. Physical Organic Chemistry "(Maruzen 1999) 187
189 pages. So HOMO
By adjusting the level, the oxidation potential can be brought close to a desired value.

Before adjusting the HOMO level of the compound,
It is necessary to keep track of this in a known manner. Conversely, it can be determined from the value of the oxidation potential, but can also be determined by calculating the HOMO level by the molecular orbital method. For the current status and specific contents of the molecular orbital method, see The Chemical Society of Japan, “Quarterly Chemistry Review No. 46 High-precision Molecular Design and New Material Development-Aiming for New Development of Functional Chemistry-” (2000)
Academic Publishing Center) 65-96 pages, supervised by Sumio Tokita, "Electronic Dyes: Current Status and Future Perspectives" (1
998 CMC) It is described on pages 20 to 25 and the like. It is preferable to calculate the molecular orbital with the highest possible accuracy and obtain an appropriate calculation result. However, it is also possible to grasp the calculation using a simple calculation method as appropriate according to the level of the required result.

Next, the relationship between the structure of the azo compound and the HOMO level will be described from the viewpoint of the substituent effect and the structure of the coloring system.

Regarding the substituent effect, see "Functional Dyes" by Shin Okawara et al. (1992 Kodansha Scientific)
39-42, "Chemistry of Functional Dyes" (CMC, 1981), pp. 43-45, Sumio Tokita et al., "Molecular Design of Functional Dyes-PPP Molecular Orbital Method and Its Utilization-"
(1989 Maruzen), pp. 89-108, etc., are described in association with the movement of the absorption wavelength and the orbital level. That is, by introducing an arbitrary substituent at a position where the coefficient of HOMO is large, for example, the HOMO level can be lowered by introducing an electron withdrawing group, and the HOMO level can be raised by introducing an electron donating group. it can.

In the case of a compound whose oxidation potential does not reach the range of the present invention, it can be improved to satisfy the conditions by introducing a substituent based on this molecular design guideline. In this case, the substituent can be selected using the Hammett's substituent constant σp value described above. At this time, it is important to grasp the molecular orbital by the above-mentioned molecular orbital method in order to grasp the coefficient of HOMO. However, there is a limit to the improvement by the substituent effect, and it can easily be assumed that the introduction of many substituents makes the dye synthesis difficult. Further, since the hue also changes at the same time, it is not easy to make the hue compatible with a good hue. Therefore, although it is possible to solve the problem of the present invention only by introducing a substituent into a known compound, it is expected that it will be very difficult.

As described above, it is difficult to freely and widely adjust the HOMO level simply by utilizing the substituent effect, and it is understood that it is necessary to devise the structure of the coloring system.

Next, the structure of the coloring system will be described. Regarding the selection of the color forming system, not only the azobenzene type structure which is the basic structure but also a heteroaryl azo type using a hetero ring may be used. Considering that it is necessary to satisfy the conditions of the oxidation potential and the absorption wavelength at the same time, the method of bringing the physical property values closer to the scope of the present invention by a method of optimizing the structure of the coloring system than the method using the substituent effect is considered. Is easy. That is,
The HOMO level of the color forming system itself was made as low as possible, the hue was brought close to the desired level, and the oxidation potential and the hue were adjusted by introducing a substituent into the color system. It can be easily inferred that the range of molecular design is greatly expanded as compared with the case. From such a viewpoint, it is considered that the compound is a heterylazo type compound.

For example, Shin Okawara et al., “Functional Dyes” (1
992, Kodansha Scientific), page 42, describes an example in which the absorption wavelength becomes longer when a heterocycle, particularly a sulfur-containing heterocycle, is used. It is considered that the use of such a color developing system broadens the range of selection of substituents that can be introduced and facilitates obtaining a compound that can achieve the object of the present invention.

Various factors affecting the coloring system of the dye include, in addition to the structure of the entire coloring system and the effect of substituents,
The fact that there are intermolecular / intramolecular interactions, solvent effects, tautomerism, acid-base equilibrium, steric effects, etc. is described in “Chemistry of Functional Dyes” (CMC, 1981), pp. 58-63.

Next, the half width in the present invention will be described. It is preferable to use a compound that is molecularly designed to have the above-mentioned half-value width because a colored image has a favorable hue. According to Sumio Tokita, “Chemistry Seminar 9 Color Chemistry” (Maruzen, 1982), pp. 150-161, hue is not only the energy level of the electronic state,
Vibration and rotation levels are always relevant. Therefore, if the contribution of vibration and rotation of the molecule is reduced, the width of the absorption band, that is, the half width is reduced, and it is expected that the absorption will be sharpened. In order to reduce the contribution of molecular vibration and rotation, there is a policy of introducing a sterically large substituent at an appropriate position in order to suppress the rotation of an arbitrary bond.

From the above experiments and considerations, it was found that the combination of the oxidation potential and the half width specified in the present invention gives a colored image having excellent ozone gas fastness and hue.

In the method for improving the fastness to ozone gas of a colored image in the present invention, a compound having a specified combination of oxidation potential and half width is used. Preferably, an azo compound represented by the following general formula (1) is used. Achieved.

[0048]

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In the formula, A and B each independently represent a substituted or unsubstituted aryl group, or a substituted or unsubstituted 5- or 6-membered hetenyl group.

The above substituted or unsubstituted aryl group is preferably a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, and specific examples include a phenyl group, a naphthyl group and an anthracenyl group. These may have a substituent. Also, two substituents on the aryl group may combine to form a condensed ring.

The above-mentioned substituted or unsubstituted 5- or 6-membered hetenyl group preferably has 3 to 3 carbon atoms.
0 is a 5- or 6-membered hetenyl group, and is a thienyl group, a furyl group, a pyrrolyl group, an indolyl group, an imidazolyl group, a pyrazolyl group, an indazolyl group, a thiazolyl group,
Examples include an isothiazolyl group, an oxazolyl group, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group, a triazolyl group, a pyridyl group, a pyrazyl group, a pyrimidyl group, a pyridazyl group, a quinolyl group, an isoquinolyl group, a phthalazinyl group, a quinoxalinyl group, and a quinazolinyl group. These may have a substituent. Two substituents on the heteryl group may combine to form a condensed ring. When a hetero atom contains a nitrogen atom, the nitrogen atom is 4
It may be graded. Preferably, at least one of A and B is a substituted or unsubstituted 5- or 6-membered hetenyl group. More preferably, A and B are substituted or unsubstituted 5- or 6-membered hetenyl groups.

The present inventors have found that among the above azo compounds,
In particular, they have found that a compound capable of achieving the object of the present invention can be designed by selecting a compound of a heterylazo type coloring system. Based on the above findings, the inventors conducted further detailed studies and found that the above-described oxidation potential, the maximum absorption wavelength, and the compound having each of the half-value widths within the above ranges can achieve the object of the present invention. Was.

Among the compounds according to the present invention, the oxidation potential is more noble than 1.0 V (vs SCE), the maximum absorption wavelength is between 500 nm and 580 nm, and the half width is 15
Specific examples of the azo compound having a thickness of 0 nm or less are shown below.
The compounds used in the present invention are not limited to the following examples.

[0054]

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[0055]

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[0056]

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[0057]

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[0058]

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As can be understood from the above specific examples, it is impossible to estimate the oxidation potential of an azo compound from its compound structure. By optimizing the various factors described above, a compound having desired physical properties can be obtained.

The method for improving the fastness to ozone gas of the present invention can be applied to an image recording material for forming an image, especially a color image. Specifically, the ink-jet recording material described below in detail, a heat-sensitive recording material, a pressure-sensitive recording material, a recording material using an electrophotographic method, a transfer silver halide photosensitive material, a printing ink, a recording pen, and the like. Yes, preferably an ink jet recording material, a thermosensitive recording material, and a recording material using an electrophotographic method, and more preferably a method for improving ozone gas fastness in an ink jet recording material. In addition, solid-state image sensors such as CCD and CMOS and L
The method of the present invention can also be applied to a color filter for recording and reproducing a color image used in a display such as a CD or PDP, and a dyeing solution for dyeing various fibers. The method of the present invention is applied by adjusting a compound with a substituent to have physical properties such as solubility, dispersibility, and heat transferability suitable for the intended use. Also, the method of the present invention, depending on the system used, dissolved state,
It can also be applied in an emulsified and dispersed state, or even in a solid dispersed state.

[Ink for Inkjet Recording] The ink for inkjet recording can be prepared by dissolving and / or dispersing the dye of the present invention in an lipophilic medium or an aqueous medium. Preferably, an aqueous medium is used. If necessary, other additives are contained within a range that does not impair the effects of the present invention. Other additives include, for example, anti-drying agents (wetting agents), anti-fading agents, emulsion stabilizers, penetration enhancers, ultraviolet absorbers, preservatives,
Known additives such as a fungicide, a pH adjuster, a surface tension adjuster, an antifoaming agent, a viscosity adjuster, a dispersant, a dispersion stabilizer, a rust inhibitor, a chelating agent and the like can be mentioned. These various additives are added directly to the ink liquid in the case of a water-soluble ink. When the oil-soluble dye is used in the form of a dispersion, it is generally added to the dispersion after the preparation of the dye dispersion, but may be added to the oil phase or the aqueous phase during the preparation.

The above-mentioned anti-drying agent is suitably used for the purpose of preventing clogging due to drying of the ink-jet ink at the ink jet opening of the nozzle used in the ink-jet recording system.

As the anti-drying agent, a water-soluble organic solvent having a lower vapor pressure than water is preferable. 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 And lower alkyl ethers of polyhydric alcohols such as ethylene glycol monomethyl (or ethyl) ether, diethylene glycol monomethyl (or ethyl) ether, and triethylene glycol monoethyl (or butyl) ether. , 2-pyrrolidone, N-methyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, N-ethylmorpholine and other heterocycles, sulfolane, dimethyl sulfoxide, 3 Sulfur-containing compounds such as sulfolane, diacetone alcohol, polyfunctional compounds such as diethanolamine, and urea derivatives. Of these, polyhydric alcohols such as glycerin and diethylene glycol are more preferred. The above-mentioned drying inhibitors may be used alone or in combination of two or more. These anti-drying agents are contained in the ink in an amount of 10 to 50% by mass.
It is preferred to contain.

The penetration enhancer is suitably used for the purpose of better penetrating the ink-jet ink into paper.
Examples of the penetration enhancer include alcohols such as ethanol, isopropanol, butanol, di (tri) ethylene glycol monobutyl ether, and 1,2-hexanediol, sodium lauryl sulfate, sodium oleate, and a nonionic surfactant. it can. If these are contained in the ink in an amount of 5 to 30% by mass, they usually have a sufficient effect, and it is preferable to use them in a range of an addition amount that does not cause bleeding of a print and print-through.

The ultraviolet absorber is used for the purpose of improving the storability of an image. Examples of the ultraviolet absorber include JP-A-58-185677 and JP-A-61-90537.
Gazette, JP-A-2-782, 5-197070
Benzotriazole compounds described in JP-A-9-34057, JP-A-46-2784,
JP-A-5-194483, U.S. Pat. No. 32144
No. 63, etc., JP-B-48-30492, JP-B-56-21141,
Cinnamic acid-based compounds described in JP-A-10-88106, JP-A-4-298503, JP-A-8-534
No. 27, No. 8-239368, No. 10-18
No. 2621, Japanese Translation of PCT International Publication No. 8-501291, and the like. Compounds described in No. 24239 and compounds emitting fluorescent light by absorbing ultraviolet light represented by stilbene-based and benzoxazole-based compounds, so-called fluorescent whitening agents, can also be used.

The anti-fading agent is used for the purpose of improving the storability of an image. As the anti-fading agent, various organic and metal complex-based anti-fading agents can be used. Hydroquinones as organic anti-fading agents,
Alkoxyphenols, dialkoxyphenols,
There are phenols, anilines, amines, indans, chromans, alkoxyanilines, heterocycles, and the like, and metal complexes include nickel complexes and zinc complexes. More specifically, Research Disclosure No.
No. 17643, Sections VII I through J; 1516
2, the same No. No. 18716, left column, page 650; 36
No. 544, page 527; 307105, page 872,
No. Compounds described in the patent cited in US Pat. No. 15,162, and pages 127 to 13 of JP-A-62-215272.
The compounds included in the general formulas and the exemplary compounds of the representative compounds described on page 7 can be used.

Examples of the fungicide include sodium dehydroacetate, sodium benzoate and sodium pyridinethione.
Examples include 1-oxide, ethyl p-hydroxybenzoate, 1,2-benzisothiazolin-3-one, and salts thereof. These are contained in the ink
It is preferred to use 1.00% by mass.

As the pH adjuster, the neutralizer (organic base, inorganic alkali) can be used. The pH
The adjuster is used for improving the storage stability of the ink-jet ink, and the ink-jet ink has a pH of 6 to 10.
It is preferable to add so that it may become, and it is more preferable to add so that it may be set to pH7-10.

Examples of the surface tension modifier include nonionic, cationic and anionic surfactants. still,
The surface tension of the inkjet ink of the present invention is 20 to 6
0 mN / m is preferred. Furthermore, 25 to 45 mN / m is preferable. The viscosity of the inkjet ink of the present invention is preferably 30 mPa · s or less. It is more preferable to adjust the pressure to 20 mPa · s or less.

Examples of the surfactant include fatty acid salts,
Anionic surfactants such as alkyl sulfate salts, alkyl benzene sulfonates, alkyl naphthalene sulfonates, dialkyl sulfosuccinates, alkyl phosphate esters, naphthalene sulfonic acid formalin condensates, and polyoxyethylene alkyl sulfate salts, Nonionics such as 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, and oxyethylene oxypropylene block copolymer Surfactants are preferred. Also, SURFYNOLS, an acetylene-based polyoxyethylene oxide surfactant,
(Air Products & Chemicals) is also preferably used. Further, amine oxide type amphoteric surfactants such as N, N-dimethyl-N-alkylamine oxide are also preferable. Further, JP-A-59-157,
No. 636, pp. 37-38, Research Disclosure No. 308119 (1989) can also be used.

As the defoaming agent, a fluorine-based or silicone-based compound, a chelating agent represented by EDTA, or the like can be used as required.

When the compound of the present invention is dispersed in an aqueous medium, JP-A-11-286637, JP-A-2000-78491 and JP-A-2000-78491 disclose the same.
No. 0-80259, or disperse colored fine particles containing a dye and an oil-soluble polymer in an aqueous medium as described in 2000-62370,
Japanese Patent Application Nos. 2000-78454, 2000-78491, 2000-203856
As described in JP-A Nos. 2000-203857 and 2000-203857, it is preferable to disperse the dye of the present invention dissolved in a high-boiling organic solvent in an aqueous medium. The specific method for dispersing the dye of the present invention in an aqueous medium, the oil-soluble polymer to be used, the high-boiling organic solvent, the additive and the amount of use thereof are preferably those described in the above patent. it can. Alternatively, the azo compound may be dispersed as fine particles in a solid state. At the time of dispersion, a dispersant or a surfactant can be used.
Examples of the dispersing device include a simple stirrer or impeller stirring method, an in-line stirring method, a mill method (for example, a colloid mill, a ball mill, a sand mill, an attritor, a roll mill, an agitator mill, etc.), an ultrasonic method, a high-pressure emulsifying dispersion method (a high-pressure homogenizer). A specific commercially available apparatus such as a Gaulin homogenizer, a microfluidizer, DeBEE2000, etc.).
Regarding the method of preparing the above ink for inkjet recording, besides the above-mentioned patents, JP-A-5-148436, JP-A-5-295512, JP-A-7-97541, and JP-A-7-82.
Nos. 515 and 7-118584, JP-A-11-286
No. 637 and Japanese Patent Application No. 2000-87539 are described in detail, and can be used for preparing the ink for inkjet recording of the present invention.

As the aqueous medium, a mixture containing water as a main component and optionally adding a water-miscible organic solvent can be used. Examples of the water-miscible organic solvent 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 (For example, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene 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 Ether, ethylene glycol diacetate, ethylene glycol monomethyl ether acetate, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, ethylene glycol monophenyl ether), amine (for example, ethanolamine, diethanolamine, triethanolamine, N-methyldiethanolamine) , N-ethyldiethanolamine, morpholine, N-ethylmorpholine, ethylenediamine, 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). The water-miscible organic solvent may be used in combination of two or more.

The ink for ink jet recording 10 of the present invention
0.2 parts by mass or more of the compound of the present invention in 0 parts by mass.
It is preferable that the content is not more than part by mass. Further, the ink-jet ink of the present invention may use another dye together with the compound of the present invention. When two or more dyes are used in combination, the total content of the dyes is preferably within the above range.

The ink jet recording ink of the present invention comprises
It can be used not only for monochromatic image formation but also for full-color image formation. To form a full-color image,
Magenta color ink, cyan color ink, and yellow color ink can be used, and further black color ink may be used to adjust the color. Any applicable yellow dye can be used. For example, aryl or hetarylazo dyes having phenols, naphthols, anilines, heterocycles such as pyrazolone and pyridone, open-chain active methylene compounds as coupling components (hereinafter referred to as coupler components); Azomethine dyes having open-chain active methylene compounds; methine dyes such as benzylidene dyes and monomethine oxonol dyes; quinone dyes such as naphthoquinone dyes and anthraquinone dyes; and other dyes Examples of the species include quinophthalone dyes, nitro / nitroso dyes, acridine dyes, and acridinone dyes.

As the applicable magenta dye, any desired one can be used together with the compound of the present invention. For example, aryl or hetenylazo dyes having phenols, naphthols, anilines and the like as coupler components; azomethine dyes having pyrazolones and pyrazolotriazoles as coupler components; for example, arylidene dyes, styryl dyes, merocyanine dyes, cyanine dyes, Methine dyes such as oxonol dyes; carbonium dyes such as diphenylmethane dyes, triphenylmethane dyes, xanthene dyes, etc .; condensed polycycles such as quinone dyes such as naphthoquinone, anthraquinone, anthrapyridone, etc .; Dyes and the like can be mentioned.

Any applicable cyan dye can be used. For example, aryl or hetenyl azo dyes having phenols, naphthols, and anilines as coupler components; azomethine dyes having phenols, naphthols, heterocycles such as pyrrolotriazole as coupler components; cyanine dyes, oxonol dyes, Polymethine dyes such as merocyanine dyes; carbonium dyes such as diphenylmethane dyes, triphenylmethane dyes and xanthene dyes; phthalocyanine dyes; anthraquinone dyes; indigo / thioindigo dyes.

Each of the above dyes may exhibit each color of yellow, magenta and cyan only after a part of the chromophore dissociates, and in this case, the counter cation is an inorganic metal such as an alkali metal or ammonium. It may be a cation, an organic cation such as a pyridinium or quaternary ammonium salt, or a polymer cation having such a partial structure. Examples of applicable black materials include disazo, trisazo, and tetraazo dyes as well as carbon black dispersions.

[Ink-Jet Recording Method] In the ink-jet recording method of the present invention, a known image-receiving material, that is, plain paper or resin-coated paper, for example, disclosed in JP-A-8-169172, JP-A-8-27693, JP-A-2-276670, JP-A-7-276789, JP-A-9-323475, JP-A-62-238873, JP-A-10-
No. 153989, No. 10-217473, No. 10-235995, No. 10-337947, No. 10-217597, No. 10-33794
An image is formed on ink-jet dedicated paper, film, electrophotographic common paper, fabric, glass, metal, porcelain, and the like described in Japanese Patent Publication No. 7 and the like.

In forming an image, a polymer latex compound may be used in combination for the purpose of imparting glossiness or water resistance or improving weather resistance. Regarding the time of applying the latex compound to the image receiving material, before, after, or simultaneously with the application of the colorant, it may be performed at the same time. It may be in the ink, or may be used as a liquid material of the polymer latex alone. Specifically, Japanese Patent Application No. 2000-363090,
2000-315231, 2000-354380, 2000-343944, 200
0-268952, 2000-299465 and 2000-297365 can be preferably used.

The recording paper and recording film used for ink-jet printing using the ink of the present invention will be described below. The support in recording paper and recording film is made of chemical pulp such as LBKP, NBKP, G
P, PGW, RMP, TMP, CTMP, CMP, CG
It consists of mechanical pulp such as P, waste paper pulp such as DIP,
If necessary, conventionally known pigments, binders, sizing agents,
Mix additives such as fixing agent, cationic agent, paper strength agent,
Those manufactured by various apparatuses such as a fourdrinier paper machine and a round paper machine can be used. In addition to these supports, any of synthetic paper and plastic film sheet may be used. The support has a thickness of 10 to 250 μm and a basis weight of 10 to 250 g.
/ M ² is desirable. The support may be provided with an ink receiving layer and a back coat layer as they are, or after providing a size press or an anchor coat layer with starch, polyvinyl alcohol or the like, and then providing an ink receiving layer and a back coat layer. Further, the support may be subjected to a flattening treatment using a calender such as a machine calender, a TG calender, and a soft calender. In the present invention, as the support,
Paper and plastic films laminated on both sides with a polyolefin (eg, polyethylene, polystyrene, polyethylene terephthalate, polybutene, and copolymers thereof) are more preferably used. It is preferable to add a white pigment (for example, titanium oxide, zinc oxide) or a coloring dye (for example, cobalt blue, ultramarine, neodymium oxide) to the polyolefin.

In the ink receiving layer provided on the support,
Contains a pigment and an aqueous binder. As the pigment, a white pigment is preferable, and as the white pigment, calcium carbonate, kaolin, talc, clay, diatomaceous earth, synthetic amorphous silica, aluminum silicate, magnesium silicate, calcium silicate, aluminum hydroxide, alumina, lithopone, zeolite, Examples include white inorganic pigments such as barium sulfate, calcium sulfate, titanium dioxide, zinc sulfide, and zinc carbonate, and organic pigments such as styrene pigment, acrylic pigment, urea resin, and melamine resin. As the white pigment contained in the ink receiving layer, a porous inorganic pigment is preferable, and synthetic amorphous silica having a large pore area is particularly preferable. As the synthetic amorphous silica, both silicic anhydride obtained by a dry production method and hydrous silicic acid obtained by a wet production method can be used, and it is particularly preferable to use hydrous silicic acid.

Examples of the aqueous binder contained in the ink receiving layer include polyvinyl alcohol, silanol-modified polyvinyl alcohol, starch, cationized starch, casein, gelatin, carboxymethylcellulose, hydroxyethylcellulose, polyvinylpyrrolidone, polyalkylene oxide, and polyalkylene oxide derivative. Such as water-soluble polymers, styrene butadiene latex,
A water-dispersible polymer such as an acrylic emulsion can be used. 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 the pigment and peel resistance of the ink receiving layer. The ink receiving layer may contain a mordant, a water-proofing agent, a lightfastness improving agent, a surfactant, and other additives in addition to the pigment and the aqueous binder.

The mordant added to the ink receiving layer is preferably immobilized. For this purpose, a polymer mordant is preferably used. Polymer mordants are described in JP-A-48-28325 and JP-A-54-74430.
No. 54-124726, No. 55-22766,
No. 55-142339, No. 60-23850, No. 6
Nos. 0-23851, 60-23852, 60-2
No. 3853, No. 60-57836, No. 60-6064
No. 3, No. 60-118834, No. 60-122940
No. 60-122941, No. 60-122942
No. 60-235134, JP-A-1-161236
Nos. 2,484,430 and 25,485.
Nos. 64, 3148061, 3309690, 4115124, 4124386, 41938
No. 00, No. 4,273,853, No. 4,282,305, and No. 4,450,224. JP 1
An image receiving material containing a polymer mordant described on pages 212 to 215 of 161236 is particularly preferred. When the polymer mordant described in the publication is used, an image having excellent image quality is obtained, and the light fastness of the image is improved.

The water-proofing agent is effective for making the image water-resistant, and a cationic resin is particularly preferable as the water-proofing agent. Examples of such a cationic resin include polyamide polyamine epichlorohydrin, polyethylene imine,
Examples thereof include polyamine sulfone, dimethyldiallylammonium chloride polymer, cationic polyacrylamide, and colloidal silica. Among these cationic resins, polyamide polyamine epichlorohydrin is particularly preferable. The content of these cationic resins is preferably from 1 to 15% by mass based on the total solid content of the ink receiving layer, and particularly preferably 3 to 15% by mass.
It is preferably from 10 to 10% by mass.

Examples of the light resistance improver include zinc sulfate, zinc oxide, hindered amine antioxidants, and benzophenone and benzotriazole ultraviolet absorbers. Of these, zinc sulfate is particularly preferred.

The surfactant functions as a coating aid, a release improver, a slipperiness improver or an antistatic agent. For the surfactant, see JP-A-62-173463.
And JP-A-62-183457. An organic fluoro compound may be used instead of the surfactant. Preferably, the organic fluoro compound is hydrophobic. Examples of the organic fluoro compound include a fluorinated surfactant, an oily fluorinated compound (for example, fluorinated oil), and a solid fluorinated compound resin (for example, ethylene tetrafluoride resin). Regarding the organic fluoro compound, JP-B-57-9053 (columns 8 to 17) and JP-A-61-2
Nos. 0994 and 62-135826. Other additives added to the ink receiving layer include a pigment dispersant, a thickener, a defoamer, a dye, a fluorescent whitening agent,
Preservatives, pH adjusters, matting agents, hardening agents and the like can be mentioned. The ink receiving layer may be a single layer or two layers.

The recording paper and the recording film may be provided with a back coat layer, and the components that can be added to this layer include a white pigment, an aqueous binder and other components. Examples of the white pigment contained in the back coat 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,
Examples include white inorganic pigments such as hydrohaloysite, magnesium carbonate, and magnesium hydroxide, and organic pigments such as styrene plastic pigment, acrylic plastic pigment, polyethylene, microcapsules, urea resin, and melamine resin.

As the aqueous binder contained in the back coat layer, styrene / maleate copolymer, styrene / acrylate copolymer, polyvinyl alcohol, silanol-modified polyvinyl alcohol, starch, cationized starch, casein, gelatin And water-soluble polymers such as carboxymethylcellulose, hydroxyethylcellulose and polyvinylpyrrolidone, and water-dispersible polymers such as styrene-butadiene latex and acrylic emulsion. Other components contained in the back coat layer include an antifoaming agent, an antifoaming agent, a dye, a fluorescent whitening agent, a preservative, and a waterproofing agent.

A polymer latex may be added to the constituent layers (including the back coat layer) of the ink jet recording paper and the recording film. The polymer latex is used for the purpose of improving film physical properties such as dimensional stabilization, curl prevention, adhesion prevention, and film crack prevention. Polymer latex is described in JP-A-62-245258 and JP-A-62-1.
It is described in each publication of 316648 and 62-110066. When a polymer latex having a low glass transition temperature (40 ° C. or lower) is added to the layer containing a mordant, cracking and curling of the layer can be prevented. Curling can also be prevented by adding a polymer latex having a high glass transition temperature to the back coat layer.

The ink of the present invention is not limited to an ink jet recording method, and is a known method, for example, a charge control method in which ink is ejected by using an electrostatic attraction, a drop-on-demand method in which vibration pressure of a piezo element is used. (Pressure pulse method), an acoustic ink jet method in which an electric signal is converted into an acoustic beam to irradiate the ink, and the ink is ejected using a radiation pressure, and a pressure is generated by heating the ink to form bubbles. Used in thermal ink jet systems and the like. The ink jet recording method uses a method of ejecting a large number of low-density inks called photo inks in a small volume, a method of improving the image quality by using a plurality of inks having substantially the same hue and different densities, or a colorless transparent ink. The method is included.

[0092]

EXAMPLES Examples of the present invention will be described below.
The present invention is not limited by these. Example 1 (Preparation of water-based ink) The following components were stirred at 30 to 40 ° C. for 1 hour while being heated, and then pressure-filtered using a micro filter having an average pore diameter of 0.8 μm and a diameter of 47 mm to obtain ink liquid A. Was prepared. -Composition of Ink Liquid A-4 parts by mass of dye (Exemplified Compound 38) 9 parts by mass of diethylene glycol 9 parts by mass of tetraethylene glycol monobutyl ether 7 parts by mass of glycerin 1 part by mass of diethanolamine 70 parts by mass of water

Ink liquids B to F were prepared in the same manner as in the preparation of ink liquid A, except that the dye (exemplary compound 38) was changed as shown in the following table.

(Image Recording and Evaluation) Using ink liquids A to F, an ink jet printer (PM-700C, manufactured by Seiko Epson Corporation) was used to produce photo glossy paper (ink jet paper manufactured by Fuji Photo Film Co., Ltd. (Grade). The resulting image was evaluated for hue and light fastness. The hue was visually evaluated in three stages of best, good and poor. The evaluation results are shown in the following table. In Table 1 below, 〇 indicates that the hue was the best; 相 indicates that the hue was good, and x indicates that the hue was poor. Regarding the light fastness, the image density C immediately after recording was used.
After measuring i, the weather meter (Atlas C.16)
After irradiating the image with xenon light (85,000 lux) for 7 days using 5), the image density Cf was measured again, and the dye remaining rate (｛(Ci) was determined from the difference in image density before and after the xenon light irradiation.
−Cf) / Ci｝ × 100%). The image density was measured using a reflection densitometer (X-Rite310TR). The dye residual ratio was measured at three points where the reflection density was 1, 1.5, and 2.0. The evaluation results are shown in the following table. In the following table, the case where the dye remaining ratio is 80% or more at any concentration is indicated by Δ, the case where two points are less than 80% is indicated by Δ, and the case where the concentration is less than 80% at all concentrations is indicated by X. Regarding the ozone gas resistance, the image immediately after recording was left in a box in which the ozone gas concentration was set to 0.5 ppm for 24 hours, and the image density before and after the ozone gas was left under ozone gas was measured using a reflection densitometer (X-Rite310TR). It was measured and evaluated as the residual dye ratio. The reflection density was measured at three points of 1, 1.5 and 2.0. The ozone gas concentration in the box is measured by an APPLICS ozone gas monitor (model:
OZG-EM-01). When the residual ratio of the dye was 70% or more at any concentration, it was evaluated as ○.
Less than 0% was rated as Δ, and less than 70% at all concentrations was rated as ×, in three steps.

The oxidation potential of the dye is 0.1 mol · dm ⁻³
POLAROGRAPHIC ANALYZER using a graphite electrode in N, N-dimethylformamide containing tetrapropylammonium perchlorate as a supporting electrolyte (the concentration of the dye is 1 × 10 ⁻³ mol · dm ⁻³ )
It was measured by DC polarography using P-100.

The maximum absorption wavelength and half-value width of the dye were adjusted to about 5 × 10 ⁻⁵ mol · dm ^{−3 using} N, N-dimethylformamide as a solvent, and the optical path 1c
m, a Shimadzu UV-V
IS Recording Spectrophototo
200 nm to 90 nm using a meter UV-260
It was determined by measuring the absorption spectrum in the range of 0 nm.

[0097]

[Table 1]

[0098]

Embedded image

As shown in Table 1, the oxidation potential was 1.0 V
(Vs SCE), the maximum absorption wavelength is 50
Ink liquids A to D prepared using a compound having a half width of 150 nm or less between 0 nm and 580 nm produce magenta images having better hue, light fastness, and ozone gas resistance than inks E and F. It turns out to give.

Further, using the ink liquids A to D, an ink jet printer (PM-700C, manufactured by Seiko Epson Corporation) was used to make a glossy paper (MJ
A4S3P, manufactured by Seiko Epson Corporation). When the hue and the light fastness of the obtained images were evaluated, the same results as those in Table 1 were obtained.

Example 2 (Preparation of Sample 201) 5.63 g of an azo compound (Exemplary Compound 33; oil-soluble dye) and 7.04 g of sodium dioctyl sulfosuccinate were added to the following high boiling organic solvent (s-2).
4.22 g, the following high boiling point organic solvent (s-11) 5.63
g and 50 ml of ethyl acetate at 70 ° C.
500 ml of deionized water was added to this solution while stirring with a magnetic stirrer to prepare an oil-in-water type coarse particle dispersion. Next, this coarse particle dispersion is treated with a microfluidizer (MICROFLUIDEX INC) for 6 hours.
Micronization was carried out by passing 5 times at a pressure of 00 bar. The solvent was removed from the resulting emulsion using a rotary evaporator until the odor of ethyl acetate disappeared. 140 g of diethylene glycol, 50 g of glycerin, and SUR were added to the fine emulsion of the hydrophobic dye thus obtained.
FYNOL465 (Air Products & Chem)
(Icals) and 900 ml of deionized water were added to prepare an ink.

[0102]

Embedded image

(Preparation of Samples 202 to 208) Sample 201
Samples 202 to 206 were prepared in the same manner as in Sample 201, except that the azo compound (Exemplary Compound 33; oil-soluble dye) was changed to the azo compound (oil-soluble dye) shown in Table 2 below.

(Image Recording and Evaluation) Samples 201 to 208
The following evaluation was performed about the exemplary compound and the comparative compound.
The results are shown in Table 2 below. In Table 2, "hue", "paper dependence", "waterfastness" and "lightfastness" indicate that each ink-jet ink was coated on an inkjet printer (manufactured by EPSON Corporation; PM-700C). This was evaluated after an image was recorded on paper (manufactured by Fuji Photo Film Co., Ltd .; inkjet paper, photo grade).

<Hue> 390-730n of recorded image
The reflection spectrum at an interval of 10 nm in the m region was measured, and a * and b * were calculated based on the reflection spectrum based on the CIE L * a * b * color space system. The preferred hue for magenta was defined as follows.

Preferred a *: 76 or more, Preferred b *: -30 or more and 0 or less A: Preferred range for both a * and b * B: Preferred range for only one of a * and b * C: Any of a * and b * Also outside the preferred area

<Paper Dependency> The hues of the image formed on the photo glossy paper and the image separately formed on the plain paper for PPC are compared. The case where the difference between the images was large was evaluated as B (poor) and evaluated in two steps.

<Water Resistance> The photo glossy paper on which the image was formed was dried for 1 hour at room temperature, immersed in water for 30 seconds, allowed to dry naturally at room temperature, and observed for bleeding. A sample without bleeding was evaluated as A, a sample with slight bleeding as B, and a sample with much bleeding as C.

<Light resistance> The photo glossy paper on which the image was formed was irradiated with xenon light (85000 lx) for 3 days using a weather meter (Atlas CI65), and the image density before and after the xenon irradiation was measured using a reflection densitometer. (X-Rite
310TR) and evaluated as the residual dye ratio. The reflection density was measured at three points of 1, 1.5 and 2.0. In any of the concentrations, the case where the residual ratio of the dye was 70% or more was evaluated as A, and B was evaluated when one or two points were less than 70%, and C was evaluated when it was less than 70% at all concentrations.

<Ozone resistance> The photo glossy paper on which the image was formed was allowed to stand in a box having an ozone gas concentration of 0.5 ppm for 24 hours. (Rite 310TR) and evaluated as a dye residual ratio. The reflection density was measured at three points of 1, 1.5 and 2.0. The ozone gas concentration in the box was set using an ozone gas monitor (model: OZG-EM-01) manufactured by APPLICS. In any of the concentrations, if the residual ratio of the dye is 70% or more, A indicates that 1 or 2 points have less than 70% B, and
%, C was evaluated in three steps.

[0111]

[Table 2]

As is clear from Table 2, the oxidation potential was 1.
0 V (vs SCE) noble, the maximum absorption wavelength is between 500 nm and 580 nm, and the half width is 150 n
m and 20 to 20
6 shows that a magenta image having better hue, paper dependence, water resistance, light resistance, and ozone gas resistance than Samples 207 to 208 was obtained.

Example 3 The same ink prepared in Example 2 was packed in a cartridge of an ink jet printer BJ-F850 (manufactured by CANON), and an image was printed on the photo glossy paper GP-301 by the same machine. When the same evaluation as that of Example 2 was performed, the same result as that of Example 2 was obtained.

[0114]

As described above, according to the present invention, the oxidation potential is nobler than 1.0 V (vs. SCE), the maximum absorption wavelength is between 500 nm and 580 nm, and the half width is 150 nm or less. An ink composition containing the compound,
By using various coloring compositions such as an inkjet ink, a method of providing a colored image or a coloring material having excellent hue and excellent weather resistance, particularly excellent ozone gas fastness can be realized.

Continued on the front page (72) Inventor Shigeaki Tanaka 210 Nakanakanuma, Minamiashigara-shi, Kanagawa Prefecture Fuji Photo Film Co., Ltd. F-term (reference) 2C056 EA13 FC02 2H086 BA15 BA33 BA55 BA56 BA60 4J039 BA29 BC05 BC12 BC19 BC20 BC31 BC33 BC36 BC40 BC44 BC50 BC51 BC52 BC53 BC54 BC55 BC65 BC68 BC69 BC78 EA34 GA24

Claims (6)

[Claims] An oxidation potential is nobler than 1.0 V (vs SCE), and a maximum absorption wavelength is from 500 nm to 580 n.
m, a method for improving the ozone gas fastness of a colored image using a compound having a half width of 150 nm or less. 2. The method for improving ozone gas fastness of a colored image according to claim 1, wherein the compound is an azo compound. 3. The method for improving ozone gas fastness of a colored image according to claim 2, wherein the azo compound is represented by the following general formula (1). Embedded image In the formula, A and B each independently represent a substituted or unsubstituted aryl group, or a substituted or unsubstituted 5- or 6-membered hetenyl group. 4. The method for improving ozone gas fastness of a colored image according to claim 1, wherein a colored composition containing the compound is used. 5. The method for improving ozone gas fastness of a colored image according to claim 4, wherein the coloring composition is selected from an ink composition and an inkjet ink. 6. An ink-jet recording method comprising forming an image on an image-receiving material having an ink-receiving layer containing white inorganic pigment particles on a support, using the ink-jet ink according to claim 5.