JP2003138185A - Ink composition, recording medium, inkjet recording method, and recorded matter - Google Patents

Abstract

(57) [Problem] To provide an ink composition, an ink jet recording method, and a recorded matter capable of obtaining a high-quality image excellent in gas resistance of the recorded matter. SOLUTION: The aqueous ink composition contains at least one thiol compound. The content of the thiol-based compound is 0.1% by weight or more in the ink composition,
It is preferably at most 10% by weight. The colorant may be a metal complex such as copper phthalocyanine. The ink composition of the present invention is liquid at least in a temperature range of 0 to 40 ° C., has a solubility in water of 1% by weight or more at a temperature of 20 ° C., and has a saturated vapor pressure of 1% at a temperature of 20 ° C. At least one water-soluble organic solvent having a pressure of 0.7 Pa or less may be contained.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an ink composition, a recording medium, an inkjet recording method, and a recorded matter,
In particular, the present invention relates to an ink composition, a recording medium, an inkjet recording method, and a recorded matter which are excellent in the storage stability of the recorded matter and can obtain a high quality image.

[0002]

2. Description of the Related Art An ink jet recording method is a printing method in which a small droplet of an ink composition is ejected and adhered to a recording medium such as paper for recording. This method has a feature that a clear image with high resolution can be printed at high speed while using a relatively inexpensive device.

Heretofore, various ink compositions for use in recording by this ink jet recording method have been proposed.

In recent years, there has been an increasing demand for maintaining a high quality image without deteriorating the recorded image for a long period of time. Therefore, various measures have been taken to improve the storability of the recorded image.

For example, as a method for improving the light resistance of a recorded image, JP-A-11-170686 proposes to add a specific compound to a recording liquid, and various other light resistance improvers. Has been proposed, and new colorants have been proposed.

The light resistance has been improved or improved by many of these methods, and when it is stored in a form that is shielded from the outside air and is only affected by light exposure, such as being displayed in a frame or an album. In (1), the storage stability is greatly improved, and good image quality can be maintained for a long period of time.

On the other hand, in addition to the above-described storage form, the number of cases in which a recorded image is directly displayed in the room or outdoors in a state of directly contacting the outside air such as a poster or a calendar is increasing.

However, in such a case, there is a problem that the image quality is deteriorated due to exposure to air as well as light. The cause of the deterioration of the recorded image is not clear, but it is considered to be due to the influence of various oxidizing gases such as ozone existing in the air.

Particularly, when the recorded matter is exposed to the air for a long period of time, the cyan dye is significantly deteriorated, and the recorded image may become reddish. This deterioration of the cyan dye is particularly likely to proceed when the recorded matter is stored outdoors.

As a method for improving the resistance (gas resistance) of the recorded image to these air (gas), for example, in JP-A-7-314882, a compound selected from the group consisting of thiocyanate is used for recording. A method for suppressing deterioration of a recorded image by adding it to a sheet is provided. In the case of this method, the deterioration due to gas can be effectively suppressed in the initial stage, but if it is continuously exposed to air for a long time, the effect of gas resistance will eventually be lost, and it will start to deteriorate rapidly when the effect expires. However, there is a problem that gas resistance cannot be maintained for a long period of time.

Further, Japanese Patent Laid-Open No. 8-3497 proposes to improve gas resistance by adding a thiosemicarbazide derivative or a thiocarbohydrazide derivative to an ink composition. There is a problem in terms of safety, and sufficient verification is required before use.

Therefore, it is an object of the present invention to provide an ink composition, an ink jet recording method, and a recorded matter which are excellent in gas resistance of the recorded image and can store a high quality recorded image.

[0012]

Means for Solving the Problems As a result of earnest studies, the present inventor has found that an ink composition has a composition containing a colorant, water, and at least one thiol-based compound. It has been found that the gas resistance of is improved.

With the above arrangement, a recorded image having excellent gas resistance can be obtained.

The thiol compound is preferably represented by the following general formula (A).

[0015]

[Chemical 3] (In the formula (A), R is an optionally substituted alkyl group,
It is an optionally substituted aryl group, an optionally substituted cyclohexyl group, an optionally substituted furyl group, an optionally substituted pyridyl group, or an optionally substituted pyrimidyl group. ) From the viewpoint of improving gas resistance, the thiol compound is
The ink composition preferably contains 0.1% by weight or more and 10% by weight or less.

The above-mentioned thiol compound may be added to the ink composition of the present invention in one kind, or two or more kinds thereof may be mixed and added. When mixed and added, the total content of these in the ink composition,
It is preferably 0.1% by weight or more and 10% by weight or less.

In the ink composition of the present invention, when the colorant contains a dye composed of a metal complex, it acts particularly effectively. Including a dye composed of a metal complex,
A recorded image having high image quality and excellent gas resistance can be obtained. Examples of the dye containing a metal complex include a phthalocyanine dye and a metal complex azo dye.

In the above, when the colorant contains a dye consisting of a copper complex, it acts more effectively. Particularly, when a copper phthalocyanine dye is used, a recorded image having more excellent gas resistance can be obtained. Specific examples of copper phthalocyanine include C.I. I. Direct Blue 86,
199 etc. are mentioned.

In the ink composition of the present invention, when the dye represented by the following general formula (B) is contained as the colorant, it works particularly effectively.

[0020]

[Chemical 4] (In the formula, X represents an anilino group substituted with at least one SO ₃ M, Y represents OH, Cl or a morpholino group, and M represents H, Li, Na, K, ammonium or an organic amine. When the present dye is contained, a recorded image having high image quality and excellent gas resistance can be obtained.

Specific examples of the dye represented by formula (B) are as follows.

[0022]

[Chemical 5]

[0023]

[Chemical 6]

[0024]

[Chemical 7]

[0025]

[Chemical 8] The ink composition is liquid at least in a temperature range of 0 to 40 ° C., has a solubility in water at a temperature of 20 ° C. of 1% by weight or more, and a temperature of 20 ° C.
It is preferable to contain at least one water-soluble organic solvent having a saturated vapor pressure at 1.7 ° C. of 1.7 Pa or less.
By containing a predetermined water-soluble organic solvent, it is possible to enhance the ejection stability of the ink without deteriorating the gas resistance of the recorded image.

In the above, it is preferable that the organic solvent contains at least one or more selected from the group consisting of glycerin, 1,5-pentanediol and triethylene glycol.

With the above structure, the gas resistance of the recorded image and the reliability of ink ejection can be improved.

From the viewpoint of further improving the dischargeability, the organic solvent is preferably contained in the ink composition in an amount of 10% by weight or more and 35% by weight or less.

The weight ratio of the content of the thiol compound to the content of the organic solvent is preferably in the range of 1: 3 to 1: 100.

The above ink composition may further contain at least one acetylene glycol compound. By further containing the acetylene glycol-based compound, it is possible to enhance the ejection stability of the ink without deteriorating the gas resistance of the recorded image.

The above ink composition may further contain at least one glycol ether compound. By using the glycol ether compound as the solvent, it is possible to enhance the ejection stability of the ink without deteriorating the gas resistance of the recorded image.

The above ink composition may further contain at least one humectant composed of a tertiary amine.

The recording medium of the present invention is a recording medium in which an ink receiving layer is provided on a substrate, and the ink receiving layer contains at least one thiol compound.

Further, the ink jet recording method of the present invention is for ejecting droplets of the ink composition and adhering the droplets to a recording medium for recording, and the ink composition and / or the ink composition as described above. The recording medium is used. That is, the thiol compound may be contained in the ink composition, the ink receiving layer, or both of them.

By using these recording methods, recorded matter having excellent gas resistance can be obtained.

[0036]

BEST MODE FOR CARRYING OUT THE INVENTION Preferred embodiments of the ink composition of the present invention will be described below.

The ink composition according to the present invention comprises a colorant,
It contains water and at least one thiol compound.

As the thiol compound, those represented by the following general formula (A) are preferable.

[0039]

[Chemical 9] (In the formula (A), R is an optionally substituted alkyl group,
It is an optionally substituted aryl group, an optionally substituted cyclohexyl group, an optionally substituted furyl group, an optionally substituted pyridyl group, or an optionally substituted pyrimidyl group. ) The compound represented by the general formula (A) may be either an aromatic thiol or an aliphatic thiol. As a method for synthesizing the compound represented by the general formula (A), for example, an aromatic thiol can be obtained by reacting a corresponding aryl Grignard reagent with elemental sulfur, and a corresponding alkyl halide and sodium hydrogen sulfide or thiol can be obtained. The reaction of urea gives an aliphatic thiol.

Specific examples of the compound represented by formula (A) are shown below.

[0041]

[Chemical 10] The thiol compound is preferably contained in the ink composition in an amount of 0.1% by weight or more and 10% by weight or less, and more preferably 0.5% by weight or more and 5% by weight or less. By setting the content to be preferable, it is possible to improve gas resistance of a recorded image while ensuring reliability such as ejection stability and anti-clogging property required as an ink composition for inkjet recording.

As the colorant, it is preferable to use a water-soluble dye. Specifically, the color index is classified into acid dyes, direct dyes, catalytic dyes, reactive dyes, soluble vat dyes, sulfur dyes and food dyes. And the like. In addition, even those not listed in the color index can be suitably used in many cases.

When the colorant is a dye composed of a metal complex, particularly a dye composed of a copper complex, or a dye represented by the general formula (B), the image quality is high and the gas resistance is excellent. A recorded image is obtained. Specific examples of suitable colorants include CI direct black 17, 19, 32, 3
8, 51, 62, 71, 74, 75, 112, 117,
154, 163, 168, CI Acid Black 7, 2
4, 26, 48, 52, 58, 60, 107, 109,
118, 119, 131, 140, 155, 156, 1
87, CI Food Black 1, 2, CI Reactive Black 5, CI Direct Yellow 11, 28, 33,
39, 44, 58, 86, 100, 132, 142, 3
30, CI Acid Yellow 3, 19, 23, 25, 2
9, 38, 49, 59, 62, 72, CI Basic Yellow 11, 51, CI Disperse Yellow 3, 5,
CI Reactive Yellow 2, CI Direct Red 2
3, 79, 80, 83, 99, 220, 224, 22
7, CI Acid Red 1, 8, 17, 18, 32, 3
5, 37, 42, 52, 57, 92, 115, 119,
131, 133, 134, 154, 186, 249, 2
54, 256, CI Basic Red 14, 39, CI
Disperse Red 60, CI Direct Blue 6,
8, 15, 25, 71, 76, 80, 86, 90, 10
6, 108, 123, 163, 165, 168, 19
9, 226, CI Acid Blue 9, 29, 40, 6
2, 74, 102, 104, 113, 117, 120,
175, 183, CI Basic Blue 41, CI Reactive Blue 15, CI Direct Violet 4
7, 51, 90, 94, CI Acid Violet 1
Examples include dyes represented by 1, 34, and 75 and the above-mentioned general formula (B). The addition amount of the colorant in the ink composition is preferably 0.1% by weight or more and 20% by weight or less, more preferably 0.5% by weight or more and 10% by weight or less. In particular, an ink composition containing a dye such as copper phthalocyanine or a dye represented by the general formula (B) as a colorant and containing a compound represented by the above general formula is used for various ink jet printing recordings. It is effective in improving the gas resistance of a recorded image when recorded on a medium (photo paper, matte paper, etc.).

In the ink composition of the present invention, water is used as a solvent. As the water, pure water such as ion-exchanged water, ultrafiltered water, reverse osmosis water, and distilled water, or ultrapure water can be preferably used.

The ink composition is liquid at a temperature range of at least 0 to 40 ° C. and has a temperature of 20 ° C.
At least one water-soluble organic solvent having a solubility in water at 1 ° C of 1% by weight or more and a saturated vapor pressure of the water-soluble organic solvent alone at a temperature of 20 ° C of 1.7 Pa or less, preferably 1 Pa or less. It is preferable to contain.

In measuring the saturated vapor pressure, many general methods can be used, but in the case of a low volatile solvent such as the organic solvent according to the present invention, the transpiration method (gas flow method) is used. By using, it is possible to measure more accurately.

The water-soluble organic solvent preferably contains at least one or more selected from the group consisting of glycerin, 1,5-pentanediol and triethylene glycol, and particularly preferably glycerin.

The water-soluble organic solvent is preferably contained in the ink composition in an amount of 10% by weight or more and 35% by weight or less. By setting the content to 10% by weight or more, it is possible to more favorably achieve both the storability of a recorded image and the reliability of ink ejection. From the viewpoint of further improving the storability of recorded images and the reliability of ink ejection, the content of the organic solvent is more preferably 15% by weight or more and 30% by weight or less in the ink composition.

The weight ratio of the content of the thiol compound to the content of the organic solvent is 1: 3 to 1: 100.
Is more preferable, and the range of 1:10 to 1:80 is more preferable.

The ink composition of the present invention containing the above-mentioned organic solvent having the above-mentioned characteristics can reduce the excellent gas resistance imparted by the thiol compound,
It is excellent in ejection reliability and printing quality, and particularly when it is used as an ink for inkjet recording, it is possible to prevent the ink from being dried in the nozzle and reliably prevent clogging of the nozzle.

The above ink composition may further contain at least one acetylene glycol compound. By using the acetylene glycol-based compound, it is possible to further enhance the ejection stability of the ink without deteriorating the gas resistance. It is considered that the ejection stability of the ink is increased because the acetylene glycol-based compound lowers the surface tension of the ink composition and accelerates the penetration of the ink into the recording medium.

As the acetylene glycol-based compound,
Olfine STG (trade name, manufactured by Nissin Chemical Co., Ltd.), Surfynol 104 (trade name, Air Products and Chemicals I)
nc.), Olfin E1010 (trade name, manufactured by Nisshin Chemical Co., Ltd.) and the like. The content of the acetylene glycol compound is preferably 1% by weight or more and 3% by weight or less based on the total amount of the ink composition.

The above ink composition may further contain at least one glycol ether compound. By using a glycol ether compound as the solvent, without deteriorating the gas resistance of the recorded image,
The image quality of the recorded image can be improved.

Examples of the glycol ether compound include diethylene glycol monobutyl ether, triethylene glycol monobutyl ether, propylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monomethyl ether and the like. When they are used, they may be used alone or in a mixture. You can

By using a glycol ether compound as a solvent, it is possible to enhance the ejection stability of the ink without deteriorating the gas resistance of the recorded image.

The above ink composition may further contain at least one humectant composed of a tertiary amine. By using a humectant composed of a tertiary amine together with the humectant, the ejection stability can be further improved.

Examples of tertiary amines include trimethylamine, triethylamine, triethanolamine, dimethylethanolamine, diethylethanolamine, triisopropenolamine, butyldiethanolamine and the like. These may be used alone or as a mixture. The amount of these tertiary amines added to the ink composition is
It is preferably about 0.1 to 10% by weight, more preferably
It is 0.5 to 5% by weight.

The ink composition of the present invention may further contain, if necessary, auxiliary agents generally used in ink jet recording inks. Examples of such an auxiliary agent include a pH adjuster, a chelating agent, an antiseptic agent, and a rust preventive agent.

With the above structure, the gas resistance of the recorded image can be improved.

Further, in the present invention, the thiol-based compound is effective even when applied to the recording medium as an imparting liquid separately or in addition to the ink composition. In this case, the application liquid is preferably prepared within the same range as the composition of the ink composition described above, except for the colorant.

Next, a preferred embodiment of the recording medium according to the present invention will be described.

As the ink receiving layer, a layer comprising at least an ink absorbing pigment, an ink fixing agent and a binder is known as a layer capable of reproducing color images, photographic images and the like with high image quality. The ink receiving layer of the recording medium according to the embodiment further contains a thiol compound.

As the thiol compounds, it is preferable to use the same compounds as those used in the above ink composition.

The thiol compound is preferably contained in an amount of 0.01% by weight or more and 10% by weight or less, more preferably 0.1% by weight or more and 5% by weight or less, based on the total dry weight of the ink receiving layer. Is more preferable. When the content is within the preferable range, the gas resistance of the recorded matter is remarkably improved.

As the ink absorbing pigment, one or more known white pigments can be used, and examples thereof include silica such as synthetic amorphous silica and colloidal silica, and colloidal alumina. As the white pigment, in addition to silica and alumina, light calcium carbonate, heavy calcium carbonate, magnesium carbonate, kaolin, talc, calcium sulfate, barium sulfate, titanium dioxide, zinc oxide, zinc sulfide, zinc carbonate, titanium. White, white inorganic pigments such as aluminum silicate, diatomaceous earth, calcium silicate, magnesium silicate, pseudoboehmite, aluminum hydroxide, magnesium hydroxide, lithopone, zeolite, hydrohaloysite, styrene plastic pigment, acrylic plastic pigment, Polyethylene, melamine resin,
Examples include organic pigments such as urea resins.

These ink absorbing pigments are preferably contained in an amount of 30% by weight or more and 90% by weight or less, more preferably 40% by weight or more and 80% by weight or less, based on the total dry weight of the ink receiving layer.

The ink fixing agent is particularly preferably a cationic compound, and examples thereof include a low molecular compound having a primary to tertiary amine or a quaternary ammonium salt group, an oligomer having those groups, or a polymer having these groups. . Specific examples include diallyldimethylammonium chloride polymer, diallyldimethylammonium chloride-sulfur dioxide copolymer, diallyldimethylammonium chloride-acrylamide copolymer and other diallyldimethylammonium salt polymers, diallylamine hydrochloride-sulfur dioxide copolymer, diallylmethylamine hydrochloride copolymer, Polyallylamine, polyethyleneimine, polyethyleneimine quaternary ammonium salt compounds, (meth) acrylic acid alkylammonium salt polymers, (meth) acrylamidoalkylammonium salt polymers, quaternary ammonium salt-containing ionene,
Examples thereof include polyalkyleneamine dicyandiamide ammonium salt condensates.

These ink fixing agents are preferably contained in an amount of 1% by weight or more and 30% by weight or less, more preferably 5% by weight or more and 10% by weight or less, based on the total dry weight of the ink receiving layer.

As the binder, starch derivatives such as oxidized starch, etherified starch and phosphoric acid esterified starch, cellulose derivatives such as carboxymethyl cellulose and hydroxyethyl cellulose, casein, gelatin, soybean protein, polyvinyl alcohol or its derivative, polyvinyl pyrrolidone, Conjugated diene copolymer latex such as maleic anhydride resin, styrene-butadiene copolymer, methyl methacrylate-butadiene copolymer, copolymer of acrylic acid ester and methacrylic acid ester, acrylic polymer of copolymer, etc. Acrylic polymer latex, vinyl polymer latex such as ethylene vinyl acetate copolymer, or functional group-modified polymer latex with a functional group-containing monomer such as carboxyl group of these various polymers, Water-based adhesive such as thermosetting resin such as lamin resin and urea resin, polymer or copolymer of acrylic ester and methacrylic ester such as polymethylmethacrylate, polyurethane resin, unsaturated polyester resin, vinyl chloride vinyl acetate copolymer , Polyvinyl butyral, alkyd resin, and other synthetic resin adhesives.

These binders are preferably contained in an amount of 10% by weight or more and 60% by weight or less, and more preferably 20% by weight or more and 50% by weight or less, based on the total dry weight of the ink receiving layer.

In the ink receiving layer, if necessary, known dye fixing agents (waterproofing agents), fluorescent whitening agents, surfactants, defoaming agents, pH adjusting agents, antifungal agents, and ultraviolet rays may be added. Various additives such as an absorbent and an antioxidant may be contained.

The structure of the ink receiving layer has been described above. As the ink receiving layer, silica or alumina is used as the main constituent component, and the particle size of silica or alumina,
By adjusting the content of other components, etc.,
It is particularly preferable that the porosity of the ink receiving layer is 30% or more and 80% or less. By setting the porosity to 30% or more, the absorbability of the ink to the recording medium can be surely ensured, and by setting the porosity to 80% or less, the strength can be surely imparted to the ink receiving layer.

As the base material, a sheet-shaped material made of paper or plastic is used, and either a light-transmissive material or a light-impermeable material can be used. As these base materials, conventionally known ones can be used. Specifically, as the paper, those made of wood pulp or non-wood pulp pulp raw material mainly composed of natural cellulose fibers can be mentioned, and plastics can be used. Examples of the material include polyester resin, diacetate resin, triacetate resin, acrylic resin, polycarbonate resin, polyvinyl chloride resin, polyimide resin, cellophane, and celluloid.

The recording medium of the present invention comprises:
A coating solution dissolved or dispersed in a suitable solvent such as water is applied to the above-mentioned base material by a known coating method such as a roll coating method, a spray coating method, a rod bar coating method, an air knife coating method, It can be suitably obtained by subsequent drying.
Drying after coating can be performed using a general drier, and is generally performed in the range of 100 ° C to 150 ° C.

With the above structure, a recorded matter having excellent gas resistance can be obtained.

Further, the ink jet recording method of the present invention will be described. In the inkjet recording method of the present invention, by performing inkjet recording using the ink composition, it becomes possible for a thiol-based compound to coexist in the recorded material, whereby a recorded material having excellent gas resistance is obtained. Can be obtained.

[0077]

EXAMPLES Next, the present invention will be described more specifically by way of examples, but the present invention is not limited to these examples.

(Preparation of Ink Composition) After stirring each component having a composition as shown in Table 1 at room temperature for 30 minutes, 1 μm
Each of the ink compositions was obtained by filtering with a membrane filter of m.

[0079]

[Table 1] Next, each of the above ink compositions is filled in a dedicated cartridge of the same using an inkjet printer PM800C (manufactured by Seiko Epson Corporation), and an inkjet dedicated recording medium (PM photographic paper and PM matte paper; both are Seiko Epson). OD)
Printing was performed by adjusting the applied duty so that (Optical Density) was in the range of 0.9 to 1.1. And the following evaluation was performed.

(Ozone exposure test) Constant flow type flow type gas corrosion tester GH-180 type (manufactured by Yamazaki Seiki Laboratories Co., Ltd.)
The recorded matter was exposed for a predetermined time (8 hours, 16 hours, 24 hours) under the conditions of 25 ° C., 60% RH and ozone concentration of 2 ppm.

(Outdoor exposure test) A structure consisting of only a pillar and a roof was prepared so as not to be exposed to direct sunlight and rain, and to prevent the flow of air from being obstructed by walls and obstacles. . This is installed outdoors, and the recorded material is placed in this for a predetermined time (1.5 months, 3 months, 6 months)
Exposed.

(Evaluation Criteria) After conducting the above-mentioned exposure test,
The OD of each recorded material was measured using a reflection densitometer (“SPM-1
00 ”(manufactured by Gretag) and the optical density residual rate (ROD) was determined by the following formula.

ROD (%) = (D / D ₀ ) × 100 (D: OD after exposure test, D ₀ : OD before exposure test) The ROD thus obtained was evaluated according to the following criteria.

A: ROD is 90% or more. Good gas resistance.

B: ROD is 80% or more and less than 90%. There is no problem in practical use.

C: ROD is 70% or more and less than 80%. Withstand the sight.

D: ROD is less than 70%. Not practical.

(Discharge Reliability Test) The ink cartridge filled with each ink composition was loaded in PM-800C,
After confirming that the ink composition is ejected normally in the initial stage, the main body of the PM-800C is turned off, and the temperature is 40 ° C. and the relative humidity is 2 while the ink cartridge is still loaded.
It was left in an environment of 0% RH. After leaving for a predetermined time, P
The M-800C was transferred to an environment of normal temperature, and after waiting until the temperature of the PM-800C main body fell to normal temperature, the main body power was turned on, the ink composition was ejected, and the ejection state was visually observed. At that time, if the discharge is not normal, PM-8
00C A predetermined cleaning recovery operation was performed, and the number of times of the cleaning recovery operation required until the ink composition was normally ejected was examined and evaluated according to the following evaluation criteria.

(Evaluation criteria) A: No cleaning recovery operation or normal ejection in one time.

B: Normal ejection after two or three cleaning recovery operations.

C: Normal ejection after 4 to 6 cleaning recovery operations.

D: Even if the cleaning recovery operation is performed 6 times, the discharge is not performed normally.

Table 2 shows the results of evaluation based on the above evaluation criteria.

[0094]

[Table 2] As can be seen from Table 2, the recorded images of Examples 1 to 10 using the ink composition containing the thiol compound,
All were excellent in gas resistance and discharge reliability. On the other hand, in Comparative Example 1, it can be seen that the gas resistance of the recorded image does not reach a practically sufficient level (C or higher).

(Preparation of recording medium) The base material is weighed 100 g /
m ² of high-quality paper, and 15 g of a coating liquid (weight of ink-receptive layer component: weight of water = 20: 80) obtained by mixing the ink-receptive layer components shown in Table 3 with water. It was coated so as to be / m ² . After coating, use a dryer at 130 ℃,
Drying was performed for 2 minutes to prepare recording media A to D.

[0096]

[Table 3] (Results of Printing Evaluation Test) Each of the above ink compositions and each recording medium were combined and printed as shown in Table 4, and an ozone exposure test was conducted by the same method as described above. The results of each test are shown in Table 4. As can be seen from Table 4, the recorded images of Examples 11 to 15 using the ink compositions 1 and 2 containing the thiol compound and / or the recording mediums a to c containing the thiol compound, All were excellent in gas resistance. On the other hand, it can be seen that the gas resistance of the recorded image of Comparative Example 2 has not reached a practically sufficient level.

[0097]

[Table 4]

According to the ink composition, recording medium or ink jet recording method of the present invention, a high quality image having excellent gas resistance of a recorded image can be obtained. Further, the recorded matter of the present invention is excellent in gas resistance of recorded images.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Kazuhiko Kitamura             Seiko, 3-3-3 Yamato, Suwa City, Nagano Prefecture             -In Epson Corporation (72) Inventor Tetsuya Aoyama             Seiko, 3-3-3 Yamato, Suwa City, Nagano Prefecture             -In Epson Corporation (72) Inventor Nobuo Uotani             1-1-1, Onodai, Midori-ku, Chiba City, Chiba Prefecture             Showa Denko K.K. (72) Inventor Hiroshi Takahashi             1-1-1, Onodai, Midori-ku, Chiba City, Chiba Prefecture             Showa Denko K.K. (72) Inventor Yuji Ito             1-1-1, Onodai, Midori-ku, Chiba City, Chiba Prefecture             Showa Denko K.K. F-term (reference) 2C056 EA04 EA13 FC01 FC06                 2H086 BA15 BA31 BA52 BA53 BA55                       BA59 BA60 BA62                 4J039 BC05 BC07 BC09 BC17 BC29                       BC31 BC33 BC50 BC51 BC52                       BC54 BC59 BC60 BC69 BE02                       BE12 BE22 CA06 EA34 EA42                       GA24

Claims (18)

[Claims] 1. An ink composition comprising a colorant, water, and at least one thiol compound. 2. The ink composition according to claim 1, wherein the thiol compound is represented by the following general formula (A). [Chemical 1] (In the formula (A), R is an optionally substituted alkyl group,
It is an optionally substituted aryl group, an optionally substituted cyclohexyl group, an optionally substituted furyl group, an optionally substituted pyridyl group, or an optionally substituted pyrimidyl group. ) 3. The ink composition according to claim 1, wherein the content of the thiol compound is 0.1% by weight or more and 10% by weight or less in the ink composition. 4. The ink composition according to claim 1, wherein the colorant contains a dye composed of a metal complex. 5. The ink composition according to claim 4, wherein the colorant contains a dye composed of a copper complex. 6. The ink composition according to claim 5, which contains a copper phthalocyanine dye as the colorant. 7. The ink composition according to claim 1, which contains a dye represented by the following general formula (B) as the colorant. [Chemical 2] (In the formula, X represents an anilino group substituted with at least one SO ₃ M, Y represents OH, Cl or a morpholino group, and M represents H, Li, Na, K, ammonium or an organic amine. Show.) 8. A liquid which is liquid at a temperature range of at least 0 to 40 ° C., has a solubility in water at a temperature of 20 ° C. of 1% by weight or more, and a saturated vapor pressure at a temperature of 20 ° C. of 1.7 Pa or less. The ink composition according to any one of claims 1 to 7, which contains at least one water-soluble organic solvent that is 9. The organic solvent is glycerin, 1,
The ink composition according to claim 8, which contains at least one kind or two or more kinds selected from the group consisting of 5-pentanediol and triethylene glycol. 10. The organic solvent is 1 in the ink composition.
9. The content of 0% by weight or more and 35% by weight or less.
Or the ink composition according to item 9. 11. The weight ratio of the content of the thiol compound and the content of the organic solvent is 1: 3 to 1:10.
The ink composition according to any one of claims 8 to 10, which has a range of 0. 12. The ink composition according to claim 1, further comprising at least one acetylene glycol compound. 13. The ink composition according to claim 1, further containing at least one glycol ether compound. 14. The ink composition according to claim 1, further comprising at least one moisturizing agent composed of a tertiary amine. 15. A recording medium having an ink receiving layer provided on a substrate, wherein the ink receiving layer contains at least one thiol compound. 16. An ink jet recording method for ejecting droplets of an ink composition and adhering the droplets to a recording medium for recording, wherein the ink composition is any one of claims 1 to 14. An ink jet recording method, which comprises using the ink composition according to the item 1. 17. An ink jet recording method, wherein droplets of an ink composition are ejected and the droplets are adhered to a recording medium to perform recording, wherein the recording medium according to claim 15 is used as the recording medium. And an inkjet recording method. 18. A recorded matter recorded by the inkjet recording method according to claim 16 or 17.