JPH1060334A - Water-base recording ink and ink jet recording method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a water-base recording ink which solves such a problem that a concentration gradient occurs in an ink composition when the composition is once frozen and then thawed and which is suitable for ink jet recording by forming a specified water-base dye ink composition. SOLUTION: This ink is made by using a dye as the coloring material and contains 2-8wt.% ethylene glycol or propylene glycol and 10-40wt.% [β-thioglycol, with the total of these two components accounting for 12-48wt.% of the ink composition. A water-soluble dye can be used as the dye. Although a water-soluble dye is used generally in an amount of about 0.1-10wt.% in the conventional ink composition, it can be used in an amount above that range in this ink. The solvent used comprises a mixture of water with a water-soluble organic solvent, which is limited to β-thioglycol.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an aqueous recording ink and an ink jet recording method.

[0002]

2. Description of the Related Art Ink jet recording methods include various ink discharging methods, for example, an electrostatic suction method, a method of applying mechanical vibration or displacement to ink using a piezoelectric element, and generating bubbles by heating ink. In this method, small ink droplets are formed by a method utilizing the pressure generated during printing, and a part or all of the ink droplets are attached to a recording material such as paper to perform recording.

As an ink composition used in such an ink jet recording system, there is known an ink composition obtained by dissolving or dispersing various water-soluble dyes or pigments in water or a liquid medium comprising water and a water-soluble organic solvent. And used. Such ink compositions are required to have optimal performance characteristics for that purpose. For example, sedimentation or aggregation does not occur even if the ink jet printer is not used for a long period of time, clogging does not occur at the tip of the ink jet printer head and in the ink flow path, and the printing quality is good.

When a dye and a pigment are compared, the pigment is not dissolved in the ink medium but is dispersed, but the dye is completely dissolved in the ink medium, so that the dye ink composition is compared with the pigment ink composition. Therefore, clogging hardly occurs at the tip of the ink jet printer head and in the ink flow path, and the liquid stability is far superior. For this reason, inks for ink jet printers often have a dye ink composition. Among such dye ink compositions, an aqueous dye ink composition in which a dye is dissolved in water is dominant. Such an aqueous dye ink composition has a water-soluble dye having various chemical structures dissolved in water and / or a mixed solvent of a water-soluble organic solvent.
At present, those to which various additives are added as needed are mainly used.

[0005]

However, in such an aqueous dye ink composition, most of the ink medium is water, so that the ink composition is easily frozen. Once such an ink composition freezes and thaws, a concentration gradient occurs in the ink composition, causing the upper color of the ink composition to be lighter and the lower color darker. When ink-jet printing is performed using the ink composition having such a concentration gradient, the color tone of the obtained image changes, and a good image that should be obtained cannot be obtained. Such a freeze-thaw phenomenon actually occurs in a cold region or the like and is a problem.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problem, that is, a problem that a concentration gradient occurs in the ink composition once the ink composition is frozen and thawed. It is an object of the present invention to provide a recording aqueous ink suitable for recording.

[0007]

To achieve this object, the recording aqueous ink according to the first aspect uses a dye as a coloring agent, contains 2 to 8% by weight of ethylene glycol, and further has a β- When the ink composition contains 10 to 40% by weight of thiodiglycol and the total amount of both is 12 to 48% by weight in the ink composition, even if the ink composition is frozen and thawed once, it can be used in the ink composition. The resulting density gradient is small, a good image can be obtained without changing the color tone of the image even when inkjet printing is performed, and the drying speed of the ink on the paper surface is fast, so that a recording aqueous ink suitable for inkjet recording can be obtained. It is made.

Further, the aqueous recording ink according to the second aspect uses a dye as a colorant, contains 2 to 8% by weight of propylene glycol, and further contains 1-β-thiodiglycol.
When the ink composition contains 0 to 40% by weight and the total amount of both is 12 to 48% by weight in the ink composition, even if the ink composition is once frozen and thawed, the concentration gradient generated in the ink composition is reduced. As a result, a good image can be obtained without changing the color tone of the image even when ink-jet printing is performed, and the drying speed of the ink on paper is high, so that a water-based recording ink suitable for ink-jet recording is produced.

Further, an ink jet recording method for performing recording using the aqueous recording ink according to claim 3 is provided.
By using the aqueous recording ink described, even if the ink composition is frozen and thawed once, the concentration gradient generated in the ink composition is reduced, and the color tone of the image is not changed even when inkjet printing is performed. Thus, a water-based recording ink suitable for inkjet recording can be produced.

Further, an ink jet recording method for performing recording using the recording water-based ink according to claim 4 is provided.
By using the aqueous recording ink described, even if the ink composition is frozen and thawed once, the concentration gradient generated in the ink composition is reduced, and the color tone of the image is not changed even when inkjet printing is performed. Thus, a water-based recording ink suitable for inkjet recording can be produced.

[0011]

Embodiments of the present invention will be described below.

The dye used in the present invention includes:
Water-soluble dyes such as direct dyes, acid dyes, basic dyes, and reactive dyes can be used. In particular, those which are suitable as inks of an ink jet recording system and satisfy the required performances such as sharpness, water solubility, stability, light fastness and the like include, for example, C.I. I. Direct Black 17, 19,
32, 51, 71, 108, 146, 154, 168;
C. I. Direct Blue 6, 22, 25, 71, 8
6, 90, 106, 199; I. Direct red 1, 4, 17, 28, 83, 227; I. Direct yellow 12, 24, 26, 86, 98, 142;
C. I. Direct orange 34, 39, 44, 46,
60; I. Direct violet 47, 48;
C. I. Direct brown 109; I. Direct green 59; I. Acid Black 2, 7, 2
4, 26, 31, 52, 63, 112, 118;
I. Acid Blue 9, 22, 40, 59, 93, 10
2, 104, 117, 120, 167, 229, 23
4; I. Acid Red 1, 6, 32, 37, 5
1, 52, 80, 85, 87, 92, 94, 115, 1
80, 249, 256, 289, 315, 317;
I. Acid Yellow 11, 17, 23, 25, 29,
42, 61, 71; I. Acid orange 7, 1
9; I. Acid violet 49; C.I. I. Basic black 2; I. Basic Blue 1, 3,
5, 7, 9, 24, 25, 26, 28, 29; I.
Basic Red 1, 2, 9, 12, 13, 14, 3,
7; I. Basic violet 7, 14, 27;
C. I. Food Black 1, 2 and the like. The above dyes are particularly preferable for the ink composition applicable to the recording method of the present invention, but the present invention is not limited to these dyes.

Such a water-soluble dye is generally used in a proportion of about 0.1 to 10% by weight in a conventional ink composition, but in the present invention, the water-soluble dye is used in the above range. Of course, the ink composition is stable even when used in an amount greater than the conventional amount, and does not produce a precipitate.

The content of ethylene glycol or propylene glycol used in the present invention in the ink composition is 2 to 8% by weight. If it is less than 2% by weight, even if the ink composition is frozen and thawed once, the effect of reducing the concentration gradient generated in the ink composition is not exhibited, and 8% by weight.
This is because the effect does not change even if it is added in a larger amount, and adversely affects the drying speed of the ink on the paper surface extremely slow.

The solvent used in the present invention is a mixed solvent of water and a water-soluble organic solvent. As the water, it is desirable to use deionized water instead of general water containing various ions. The water-soluble organic solvent mainly has an effect of preventing the ink from drying at the tip of the ink jet head. Generally, polyhydric alcohols are often used as such an organic solvent, but the water-soluble organic solvent used in the present invention is limited to β-thiodiglycol. By combining this water-soluble organic solvent with the above-mentioned ethylene glycol or propylene glycol, even if the ink composition is frozen and thawed, the effect of reducing the concentration gradient generated in the ink composition is synergistically exhibited. You. The content of this water-soluble organic solvent in the ink composition is limited to the range of 10 to 40% by weight. If the content is less than 10% by weight, the effect of preventing the ink from drying at the tip of the inkjet head and the effect of reducing the concentration gradient generated in the ink composition even if the ink composition is frozen and thawed are not sufficiently exhibited. If the content exceeds 40% by weight, adverse effects such as an extremely slow drying speed of the ink on the paper surface appear.

That is, the content of ethylene glycol or propylene glycol in the ink composition is 2 to 8% by weight, the content of β-thiodiglycol in the ink composition is 10 to 40% by weight, and When the total amount thereof is 12 to 48% by weight in the ink composition, an excellent effect of preventing drying at the tip of the ink jet head and an excellent effect of not causing a concentration gradient due to freezing and thawing are simultaneously exhibited. In addition, the drying speed of the ink on the paper is high.

The basic composition of the ink composition of the present invention is as described above, but other conventionally known various additives such as a pH adjuster, a surfactant, a viscosity adjuster, a surface tension adjuster, a fungicide and the like. Can be added as needed. Examples thereof include viscosity modifiers such as polyvinyl alcohol, celluloses, and water-soluble resins, and various surfactants such as cations, anions, and nonionics. When preparing an ink composition used in an ink jet recording method of charging a recording liquid, a specific resistance adjusting agent such as an inorganic salt such as ammonium chloride is added.

Next, examples and comparative examples of the present invention will be described, but the present invention is not limited to these examples.

[0019]

【Example】

Example 1 Pure water (86 parts by weight) was mixed with a yellow dye “Daiwa IJ YEL”.
LOW 307H "(2 parts by weight, manufactured by Daiwa Kasei Co., Ltd.), ethylene glycol (2 parts by weight), and β-thiodiglycol (10 parts by weight) were added, and the mixture was stirred for 30 minutes and then passed through a membrane filter having a pore size of 0.7 μm. After filtration, a yellow ink composition was obtained.

The ink composition was sealed in a heat-resistant bottle, frozen at a low temperature, and then naturally thawed. 1 g of the ink composition was collected from the bottom of the bottle and diluted 200 times with pure water.
Similarly, 1 g of an unfrozen ink composition was collected and purified with pure water.
Diluted 00-fold. The transmission color of these dilutions were measured illuminant D ₆₅ 2 ° visual field, the measurement conditions of the transmission optical path length 10 mm, color difference Delta] E * a to the unfrozen ink composition based
When b was calculated, ΔE * ab = 1.66.

When the unfrozen ink composition and the freeze-thawed ink composition were respectively printed using a shear mode type ink jet head disclosed in Japanese Patent Application Laid-Open No. 2-150355, the jetting was good. Yes,
A good image was obtained without the color tone of the image changing by freeze-thawing. In addition, even if the printing surface was touched with a finger 15 seconds after printing, the ink did not adhere to the finger, and the drying speed of the ink on the paper surface was high.

Example 2 Pure water (50 parts by weight) was mixed with a yellow dye “Daiwa IJ YEL”.
LOW 307H "(2 parts by weight, manufactured by Daiwa Kasei Co., Ltd.), ethylene glycol (8 parts by weight) and β-thiodiglycol (40 parts by weight) were added, and the mixture was stirred for 30 minutes and then filtered with a membrane filter having a pore diameter of 0.7 μm. After filtration, a yellow ink composition was obtained.

The ink composition was sealed in a heat-resistant bottle, frozen at a low temperature, and then naturally thawed. 1 g of the ink composition was collected from the bottom of the bottle and diluted 200 times with pure water.
Similarly, 1 g of an unfrozen ink composition was collected and purified with pure water.
Diluted 00-fold. The transmission color of these dilutions were measured illuminant D ₆₅ 2 ° visual field, the measurement conditions of the transmission optical path length 10 mm, color difference Delta] E * a to the unfrozen ink composition based
When b was calculated, ΔE * ab = 1.30.

When the unfrozen ink composition and the freeze-thawed ink composition were respectively printed by using a shear mode type ink jet head disclosed in Japanese Patent Application Laid-Open No. 2-150355, the ejection was good. Yes,
A good image was obtained without the color tone of the image changing by freeze-thawing. In addition, even if the printing surface was touched with a finger 15 seconds after printing, the ink did not adhere to the finger, and the drying speed of the ink on the paper surface was high.

Example 3 A yellow ink composition was obtained in the same manner as in Example 1 except that propylene glycol was used instead of ethylene glycol.

When the same study as in Example 1 was conducted for this ink composition, ΔE * ab = 1.72.

When the unfrozen ink composition and the freeze-thawed ink composition were respectively printed using a shear mode type ink jet head disclosed in Japanese Patent Application Laid-Open No. 2-150355, the jetting was good. Yes,
A good image was obtained without the color tone of the image changing by freeze-thawing. In addition, even if the printing surface was touched with a finger 15 seconds after printing, the ink did not adhere to the finger, and the drying speed of the ink on the paper surface was high.

Example 4 A yellow ink composition was obtained in the same manner as in Example 2 except that propylene glycol was used instead of ethylene glycol.

When the same study as in Example 1 was conducted for this ink composition, ΔE * ab = 1.35.

When the unfrozen ink composition and the frozen and thawed ink composition were respectively printed using a shear mode type ink jet head disclosed in Japanese Patent Application Laid-Open No. 2-150355, the ejection was good. Yes,
A good image was obtained without the color tone of the image changing by freeze-thawing. In addition, even if the printing surface was touched with a finger 15 seconds after printing, the ink did not adhere to the finger, and the drying speed of the ink on the paper surface was high.

Comparative Example 1 An ink was prepared in Example 1 without ethylene glycol, and the same experiment was conducted. As a result, ΔE * ab = 6.80. When the ink composition after freezing and thawing was printed in the same manner, the yellow color became deeper than in Example 1, and a good image was not obtained.

Comparative Example 2 An ink was prepared in the same manner as in Example 1 except that ethylene glycol was used as 1 part by weight.
It was 3.20. When the ink composition after freezing and thawing was printed in the same manner, the yellow color became deeper than in Example 1, and a good image was not obtained.

Comparative Example 3 A yellow dye “Daiwa IJ YEL” was added to pure water (48 parts by weight).
LOW 307H "(2 parts by weight, manufactured by Daiwa Kasei Co., Ltd.), ethylene glycol (15 parts by weight), and β-thiodiglycol (35 parts by weight) were added, and the mixture was stirred for 30 minutes and then filtered with a membrane filter having a pore diameter of 0.7 μm. After filtration, a yellow ink composition was obtained.

The ink composition was sealed in a heat-resistant bottle, frozen at a low temperature and then naturally thawed. 1 g of the ink composition was collected from the bottom of the bottle and diluted 200 times with pure water.
Similarly, 1 g of an unfrozen ink composition was collected and purified with pure water.
Diluted 00-fold. The transmission color of these dilutions were measured illuminant D ₆₅ 2 ° visual field, the measurement conditions of the transmission optical path length 10 mm, color difference Delta] E * a to the unfrozen ink composition based
When b was calculated, ΔE * ab = 1.31.

The unfrozen ink composition and the frozen and thawed ink composition were respectively printed using a shear mode type ink jet head disclosed in Japanese Patent Application Laid-Open No. 2-150355. Since 3
When the print surface was touched with a finger a minute later, the ink adhered to the finger, and the drying speed of the ink on the paper surface was low.

Comparative Example 4 A pure yellow water (88 parts by weight) was mixed with a yellow dye “Daiwa IJ YEL”.
LOW 307H "(2 parts by weight, manufactured by Daiwa Kasei Co., Ltd.), ethylene glycol (4 parts by weight), and β-thiodiglycol (6 parts by weight) were added, and the mixture was stirred for 30 minutes, and then stirred for 30 minutes.
The mixture was filtered with a 7 μm membrane filter to obtain a yellow ink composition.

This ink composition was sealed in a heat-resistant bottle, frozen at a low temperature, then naturally thawed, and 1 g of the ink composition was collected from the bottom of the bottle and diluted 200 times with pure water.
Similarly, 1 g of an unfrozen ink composition was collected and purified with pure water.
Diluted 00-fold. The transmission color of these dilutions were measured illuminant D ₆₅ 2 ° visual field, the measurement conditions of the transmission optical path length 10 mm, color difference Delta] E * a to the unfrozen ink composition based
When b was calculated, ΔE * ab = 2.50.

The unfrozen ink composition and the frozen and thawed ink composition were printed using a shear mode ink jet head disclosed in JP-A-2-150355, respectively. Was good, but began to clog while continuing to print. Observation of the clogged portion of the head with an optical microscope revealed that a yellow substance had adhered. In addition, the obtained image became deeper in yellow by freeze-thawing, and dot missing occurred due to clogging of the head, and a good image was not obtained.

Comparative Example 5 Pure water (49 parts by weight) was mixed with a yellow dye “Daiwa IJ YEL”.
LOW 307H "(2 parts by weight, manufactured by Daiwa Kasei Co., Ltd.), ethylene glycol (4 parts by weight) and β-thiodiglycol (45 parts by weight) were added, and the mixture was stirred for 30 minutes and then filtered with a membrane filter having a pore diameter of 0.7 μm. After filtration, a yellow ink composition was obtained.

The ink composition was sealed in a heat-resistant bottle, frozen at a low temperature, and then naturally thawed. 1 g of the ink composition was collected from the bottom of the bottle and diluted 200 times with pure water.
Similarly, 1 g of an unfrozen ink composition was collected and purified with pure water.
Diluted 00-fold. The transmission color of these dilutions were measured illuminant D ₆₅ 2 ° visual field, the measurement conditions of the transmission optical path length 10 mm, color difference Delta] E * a to the unfrozen ink composition based
When b was calculated, ΔE * ab = 1.35.

The unfrozen ink composition and the freeze-thawed ink composition were respectively printed using a shear mode ink jet head disclosed in JP-A-2-150355. Since 3
When the print surface was touched with a finger a minute later, the ink adhered to the finger, and the drying speed of the ink on the paper surface was low.

Comparative Example 6 An ink was prepared in the same manner as in Example 3 except that propylene glycol was 1 part by weight.
= 3.30. When the ink composition after freezing and thawing was printed in the same manner, the yellow color became deeper than in Example 3, and a good image was not obtained.

Comparative Example 7 A yellow dye "Daiwa IJ YEL" was added to pure water (48 parts by weight).
LOW 307H "(2 parts by weight, manufactured by Daiwa Kasei Co., Ltd.), propylene glycol (15 parts by weight), and β-thiodiglycol (35 parts by weight) were added, followed by stirring for 30 minutes, followed by a membrane filter having a pore diameter of 0.7 μm. After filtration, a yellow ink composition was obtained.

This ink composition was sealed in a heat-resistant bottle, frozen at a low temperature and then naturally thawed. 1 g of the ink composition was collected from the bottom of the bottle and diluted 200 times with pure water.
Similarly, 1 g of an unfrozen ink composition was collected and purified with pure water.
Diluted 00-fold. The transmission color of these dilutions were measured illuminant D ₆₅ 2 ° visual field, the measurement conditions of the transmission optical path length 10 mm, color difference Delta] E * a to the unfrozen ink composition based
When b was calculated, ΔE * ab = 1.30.

The unfrozen ink composition and the freeze-thawed ink composition were respectively printed using a shear mode type ink jet head disclosed in JP-A-2-150355. Since 3
When the print surface was touched with a finger a minute later, the ink adhered to the finger, and the drying speed of the ink on the paper surface was low.

Comparative Example 8 A yellow dye “Daiwa IJ YEL” was added to pure water (88 parts by weight).
LOW 307H "(2 parts by weight, manufactured by Daiwa Kasei Co., Ltd.), propylene glycol (4 parts by weight), and β-thiodiglycol (6 parts by weight) were added, followed by stirring for 30 minutes, followed by a membrane filter having a pore size of 0.7 μm. After filtration, a yellow ink composition was obtained.

The ink composition was sealed in a heat-resistant bottle, frozen at a low temperature and then naturally thawed. 1 g of the ink composition was collected from the bottom of the bottle and diluted 200 times with pure water.
Similarly, 1 g of an unfrozen ink composition was collected and purified with pure water.
Diluted 00-fold. The transmission color of these dilutions were measured illuminant D ₆₅ 2 ° visual field, the measurement conditions of the transmission optical path length 10 mm, color difference Delta] E * a to the unfrozen ink composition based
When b was calculated, ΔE * ab = 2.47.

The unfrozen ink composition and the freeze-thawed ink composition were respectively printed by using a shear mode type ink jet head disclosed in JP-A-2-150355. Was good, but began to clog while continuing to print. Observation of the clogged portion of the head with an optical microscope revealed that a yellow substance had adhered. In addition, the obtained image became deeper in yellow by freeze-thawing, and dot missing occurred due to clogging of the head, and a good image was not obtained.

Comparative Example 9 A yellow dye “Daiwa IJ YEL” was added to pure water (49 parts by weight).
LOW 307H "(2 parts by weight, manufactured by Daiwa Kasei Co., Ltd.), propylene glycol (4 parts by weight), and β-thiodiglycol (45 parts by weight) were added, and the mixture was stirred for 30 minutes and then filtered with a membrane filter having a pore diameter of 0.7 μm. After filtration, a yellow ink composition was obtained.

This ink composition was sealed in a heat-resistant bottle, frozen at a low temperature and then naturally thawed. 1 g of the ink composition was collected from the bottom of the bottle and diluted 200 times with pure water.
Similarly, 1 g of an unfrozen ink composition was collected and purified with pure water.
Diluted 00-fold. The transmission color of these dilutions were measured illuminant D ₆₅ 2 ° visual field, the measurement conditions of the transmission optical path length 10 mm, color difference Delta] E * a to the unfrozen ink composition based
When b was calculated, ΔE * ab = 1.40.

The unfrozen ink composition and the freeze-thawed ink composition were respectively printed using a shear mode type ink jet head disclosed in JP-A-2-150355. Since 3
When the print surface was touched with a finger a minute later, the ink adhered to the finger, and the drying speed of the ink on the paper surface was low.

Even if the ink composition is once frozen and thawed, the concentration gradient generated in the ink composition is small, the ink jetting is good even when ink-jet printing is performed, and a good image can be obtained without changing the color tone of the image. In each of the ink compositions of Examples 1 to 4, in which the drying speed of the ink on the paper surface was high, a dye was used as a coloring agent, ethylene glycol or propylene glycol was contained in an amount of 2 to 8% by weight, and β- It contained 10 to 40% by weight of thiodiglycol, and the total amount of both was 12 to 48% by weight in the ink composition.

On the other hand, after the ink composition is once frozen and thawed, the concentration gradient generated in the ink composition becomes large, the ejection becomes poor even when ink-jet printing is performed, and the color tone of the image changes, which is favorable. Comparative Examples 1 to 4 in which a good image was not obtained or the ink drying speed on the paper surface was low
In No. 9, none of the above conditions was satisfied.

[0054]

As is apparent from the above description, the aqueous recording ink according to claim 1 uses a dye as a coloring agent, contains 2 to 8% by weight of ethylene glycol, and further has a β-thiodiene. Glycol is contained in an amount of 10 to 40% by weight, and the total amount of both is 12 to 48% by weight in the ink composition. The size is small, the ejection is good even when inkjet printing is performed, a good image is obtained without changing the color tone of the image, and the drying speed of the ink on paper is fast.

The aqueous recording ink according to the second aspect uses a dye as a colorant, contains 2 to 8% by weight of propylene glycol, and further contains 1-β-thiodiglycol.
Since 0 to 40% by weight is contained and the total amount of both is 12 to 48% by weight in the ink composition, even if the ink composition is once frozen and thawed, the concentration gradient generated in the ink composition becomes small. Even when inkjet printing is performed, the ejection is good, a good image can be obtained without changing the color tone of the image, and the drying speed of the ink on paper is fast.

Further, an ink jet recording method for performing recording by using the recording aqueous ink according to the third aspect is provided.
Since the inkjet recording method using the aqueous recording ink described, the concentration gradient generated in the ink composition is reduced even if the ink composition is once frozen and thawed, and jetting is good even when inkjet printing is performed. A good image can be obtained without changing the color tone of the image, and the drying speed of the ink on the paper surface is high.

Further, an ink jet recording method for performing recording using the aqueous recording ink according to claim 4 is provided.
Since the inkjet recording method using the aqueous recording ink described, the concentration gradient generated in the ink composition is reduced even if the ink composition is once frozen and thawed, and jetting is good even when inkjet printing is performed. A good image can be obtained without changing the color tone of the image, and the drying speed of the ink on the paper surface is high.

Claims (4)

[Claims] 1. An aqueous recording ink, wherein a dye is used as a colorant and ethylene glycol is used in an amount of 2 to 2.
8% by weight, and β-thiodiglycol in an amount of 10 to 4
An aqueous recording ink containing 0% by weight and the total amount of both is 12 to 48% by weight in the ink composition. 2. A water-based recording ink, wherein a dye is used as a colorant, and propylene glycol is used as a colorant.
-8% by weight, and β-thiodiglycol in 10
An aqueous recording ink containing 40% by weight and the total amount of both is 12 to 48% by weight in the ink composition. 3. An ink jet recording method for performing recording using a recording aqueous ink, wherein the recording aqueous ink according to claim 1 is used. 4. An ink jet recording method for performing recording using a recording aqueous ink, wherein the recording aqueous ink according to claim 2 is used.