JP2001152058A - Ink jet recording liquid - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ink jet recording liquid which does not require a long time preliminary extrusion treatment because of having excellent extrusion stability even under a low humidity environment and has excellent image storability. SOLUTION: This on-demand type ink jet recording liquid comprising at least water, a coloring agent, and a plurality of high boiling point organic solvents containing ethylene glycol, characterized in that the total amount of ethylene glycol, diethylene glycol monomethyl ether, triethylene glycol monomethyl ether, diethylene glycol monoethyl ether and ρ-butyrolactone in the high boiling point organic solvents is >=80%.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording liquid for an on-demand ink jet printer, and more particularly, to an on-demand ink jet recording liquid having improved ejection stability under low humidity conditions. .

[0002]

2. Description of the Related Art In an ink jet recording method for recording information by ejecting a controlled ink jet recording liquid onto a recording material, the ink jet recording head is not brought into contact with a recording material, so that there is no noise and high-speed recording is possible. And has the advantage that it can be recorded on plain paper.

[0003] An ink jet recording liquid (hereinafter, also simply referred to as ink) used in such an ink jet recording method.
In many cases, various dyes or pigments and water or a water-soluble organic solvent for dissolving or dispersing the same as a basic component, and those to which various additives are added as necessary are known and used. I have.

[0004] Such inks must have appropriate physical properties to satisfy (1) no clogging in the nozzles of the recording head and (2) ejection characteristics (flying stability, frequency response, etc.). (3) it does not corrode materials that come into contact with the ink, (4) it has excellent long-term storage stability, and (5) it can be discharged stably in various environments. Is required.

[0005] Further, when the ink is printed on a recording material, the characteristics include (6) quick drying, (7) good printing quality, and (8) storage stability as a recorded image (lightfastness). Properties, water resistance, etc.) are required.

In particular, on-demand type ink jet printers are used very frequently because they discharge ink droplets only when necessary, so that energy is wasted little and the structure is simple. However, in an on-demand type ink jet printer, particularly in a low humidity environment, at a cap or a discharge port that has not been discharged for a certain period of time, the ink viscosity near the discharge port increases due to evaporation of water due to drying, and normal discharge is performed. There is a disadvantage that disappears.

More specifically, the velocity of the droplet at the time of ejection is reduced,
An increase in the amount of droplets due to merging with the subsequent droplets or deterioration in landing accuracy may cause an image to be disturbed. Further, ejection cannot be performed.

In order to prevent this phenomenon, it is usually effective to carry out preliminary ejection unrelated to printing in a cap or a special ejection place. However, if the recording is frequently interrupted to perform the preliminary ejection, the recording time becomes longer, which is not preferable.

[0009]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a method that does not require a long-time preliminary discharge because of excellent discharge stability even in a low humidity environment. Another object of the present invention is to provide an inkjet recording liquid having excellent image storability.

[0010]

Hereinafter, the present invention will be described in more detail.

1. At least, in an on-demand type inkjet recording liquid containing a plurality of high boiling organic solvents including water, a colorant and ethylene glycol, the amount of ethylene glycol in the high boiling organic solvent, the amount of diethylene glycol monomethyl ether, the amount of triethylene glycol monomethyl ether, An ink jet recording liquid, wherein the sum of the amounts of diethylene glycol monoethyl ether and γ-butyrolactone is 80% or more.

2. At least, in the on-demand ink jet recording liquid containing a plurality of high boiling organic solvents including water, a colorant and ethylene glycol, the total amount of ethylene glycol, diethylene glycol monomethyl ether and γ-butyrolactone in the high boiling organic solvent is 80% or more of an inkjet recording liquid.

3. In an on-demand type inkjet recording liquid containing at least a plurality of high-boiling organic solvents containing water, a colorant and ethylene glycol, the sum of the amounts of ethylene glycol and γ-butyrolactone in the high-boiling organic solvents is 80% or more. An ink jet recording liquid characterized by the above-mentioned.

4. In an on-demand ink jet recording liquid containing at least a plurality of high-boiling organic solvents containing water, a colorant and ethylene glycol, the sum of the amounts of ethylene glycol and diethylene glycol monomethyl ether in the high-boiling organic solvents is 80% or more. An ink jet recording liquid characterized by the above-mentioned.

[0015] 5. The proportion of ethylene glycol in the high boiling organic solvent is 50% to 90%, and the content of the high boiling organic solvent is 20% to 60% in the inkjet recording liquid.
5. The ink jet recording liquid according to any one of the above items 1 to 4, wherein

6. The method according to any one of the above items 1 to 3, wherein an ink jet discharge device having a minimum droplet amount of 10 pL or less is used.
6. The ink jet recording liquid according to any one of the above items 5.

That is, in the conventional ink jet printer, these phenomena were not remarkably observed because of a large amount of liquid droplets. However, in an ink jet printer having a small amount of droplets, a phenomenon that normal ejection is not performed due to drying is remarkably observed.

Because, the ease of drying is proportional to the area of the liquid in contact with air. That is, it is proportional to the square of the opening diameter. However, the droplet volume is approximately proportional to the cube of the opening diameter. Therefore, it is presumed that the ease of drying does not decrease so much even if the amount of droplets is reduced.

As a result of the study of the present inventor, it has been found that the ease of drying at the discharge port under low humidity conditions varies greatly depending on the type of high boiling organic solvent, and that the specific high boiling organic solvent cannot be dried at the discharge port. It was found that there was little drying.

Further, as a result of studies by the present inventors, γ-butyrolactone, diethylene glycol monomethyl ether, triethylene glycol monomethyl ether, diethylene glycol monoethyl ether, as well as ethylene glycol, are high-boiling organic solvents that suppress drying at the discharge port. Was found.

However, these high-boiling organic solvents cannot be used alone due to poor dye solubility. on the other hand,
When these high-boiling organic solvents were used together with ethylene glycol, it was found that the storage stability of images (especially, bleeding under high humidity conditions) was improved.

Hereinafter, the present invention will be described in more detail. The invention of claim 1 provides an on-demand ink jet recording liquid containing at least a plurality of high-boiling organic solvents containing water, a colorant and ethylene glycol, wherein the amounts of ethylene glycol and diethylene glycol monomethyl ether in the high-boiling organic solvents are And an amount of triethylene glycol monomethyl ether, an amount of diethylene glycol monoethyl ether and an amount of γ-butyrolactone are 80% or more.

Preferably, the total amount of ethylene glycol, diethylene glycol monomethyl ether, triethylene glycol monomethyl ether, diethylene glycol monoethyl ether and γ-butyrolactone in the high boiling organic solvent is 90% or more. Preferably it is 95% or more.

Further, the invention of claim 2 relates to an on-demand type ink jet recording liquid containing at least a plurality of high boiling organic solvents containing water, a colorant and ethylene glycol. ,
An inkjet recording liquid characterized in that the total amount of diethylene glycol monomethyl ether and γ-butyrolactone is 80% or more.

Preferably, the total amount of ethylene glycol, diethylene glycol monomethyl ether and γ-butyrolactone in the high boiling organic solvent is at least 90%, more preferably at least 95%.

Further, the invention according to claim 3 has at least:
In the on-demand type inkjet recording liquid containing a plurality of high boiling organic solvents including water, a colorant and ethylene glycol, the sum of the amounts of ethylene glycol and γ-butyrolactone in the high boiling organic solvent is 80% or more. An inkjet recording liquid characterized by the following.

Preferably, the total amount of ethylene glycol and γ-butyrolactone in the high boiling organic solvent is at least 90%, more preferably at least 95%.

According to a fourth aspect of the present invention, there is provided an on-demand ink jet recording liquid comprising at least a plurality of high boiling organic solvents containing water, a colorant and ethylene glycol. An ink jet recording liquid characterized in that the sum of the amount of ethylene glycol and the amount of diethylene glycol monomethyl ether therein is 80% or more.

[0029] Preferably, the inkjet recording liquid is characterized in that the sum of the amount of ethylene glycol and the amount of diethylene glycol monomethyl ether in the high-boiling organic solvent is 90% or more, and more preferably 95% or more.

The invention according to claim 5 is characterized in that the proportion of ethylene glycol in the high boiling organic solvent is 50% to 90%.
Wherein the content of the high boiling organic solvent is from 20% to
The inkjet recording liquid according to any one of claims 1 to 4, which is 60%.

Further, according to the invention of claim 6, the minimum droplet amount is 1
The ink jet recording liquid according to any one of claims 1 to 5, wherein the ink jet recording liquid is used together with an ink jet discharge device having a pressure of 0 pL or less. Preferably, the inkjet recording liquid according to any one of the first to fifth aspects of the present invention is used together with an inkjet discharge device having a minimum droplet amount of 7 pL or less, and more preferably, the minimum droplet amount is 5 pL. An inkjet recording liquid according to the first to fifth aspects of the present invention, which is used together with the following inkjet discharge device.

The colorant preferably used in the present invention is an ink jet recording liquid containing a water-soluble dye. The water-soluble dye includes a water-soluble direct dye, an acid dye, a reactive dye and a basic dye. These may be selected, and these may be used alone or in combination of two or more. These dyes are used by dissolving them in a solvent appropriately selected and used as desired. The following are representative dyes, but the present invention is not limited thereto. <Direct dye> C.I. I. Direct Yellow 1, 4, 8, 11, 12,
24, 26, 27, 28, 33, 39, 44, 50, 5
8, 85, 86, 100, 110, 120, 132, 1
42, 144, C.I. I. Direct Red 1, 2, 4, 9, 11, 1
3, 17, 20, 23, 24, 28, 31, 33, 3
7, 39, 44, 47, 48, 51, 62, 63, 7
5, 79, 80, 81, 83, 89, 90, 94, 9
5, 99, 220, 224, 227, 243, C.I. I. Direct Blue 1, 2, 6, 8, 15, 2
2, 25, 71, 76, 78, 80, 86, 87, 9
0, 98, 106, 108, 120, 123, 163,
165, 192, 193, 194, 195, 196, 1
99, 200, 201, 202, 203, 207, 23
6, 237, C.I. I. Direct Black 2, 3, 7, 17, 19,
22, 32, 38, 51, 56, 62, 71, 74, 7
5, 77, 105, 108, 112, 117, 154, <acid dye> C.I. I. Acid Yellow 2, 3, 7, 17, 19, 2
3, 25, 29, 38, 42, 49, 59, 61, 7
2, 99, C.I. I. Acid Orange 56, 64, C.I. I. Acid Red 1, 8, 14, 18, 26, 3
2, 37, 42, 52, 57, 72, 74, 80, 8
7, 115, 119, 131, 133, 134, 14
3, 154, 186, 249, 254, 256; I. Acid Violet 11, 34, 75, C.I. I. Acid Blue 1, 7, 9, 29, 87, 12
6, 138, 171, 175, 183, 234, 23
6, 249, C.I. I. Acid Green 9, 12, 19, 27, 4
1, C.I. I. Acid Black 1, 2, 7, 24, 26, 4
8, 52, 58, 60, 94, 107, 109, 11
0, 119, 131, 155, <Reactive dye> C.I. I. Reactive Yellow 1, 2, 3, 13, 1
4, 15, 17, 37, 42, 76, 95, 168, 1
75, C.I. I. Reactive Red 2, 6, 11, 21, 2
2, 23, 24, 33, 45, 111, 112, 11
4, 180, 218, 226, 228, 235, C.I. I. Reactive Blue 7, 14, 15, 18, 1
9, 21, 25, 38, 49, 72, 77, 176, 2
03, 220, 230, 235, C.I. I. Reactive Orange 5, 12, 13, 35,
95, C.I. I. Reactive Brown 7, 11, 33, 37,
46, C.I. I. Reactive Green 8, 19, C.I. I. Reactive Violet 2, 4, 6, 8, 2
1, 22, 25, C.I. I. Reactive Black 5, 8, 31, 39 <Basic dye> C.I. I. Basic Yellow 11, 14, 21, 32 C.I. I. Basic Red 1, 2, 9, 12, 13 C.I. I. Basic violet 3, 7, 14 C.I. I. Basic Blue 3, 9, 24, 25 Other dyes that can be used in the ink of the present invention include chelate dyes and azo dyes used in so-called silver dye bleaching light-sensitive materials (for example, Cibachrome from Ciba-Geigy). I can do it.

[0033] Chelating dyes are described, for example, in British Patent 1,077,484.

Regarding the azo dyes of the silver dye bleaching method light-sensitive material, for example, British Patents 1,039,458 and 1,00
Nos. 4,957 and 1,077,628; U.S. Pat.
No. 612,448.

The content of the water-soluble dye used in the ink of the present invention is preferably 1 to 10% by weight based on the total weight of the ink.

The organic solvent which can be used in the ink of the present invention and which is not described in the claims includes those having 1 to 4 carbon atoms.
(E.g., methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, sec-butyl alcohol, tert-butyl alcohol, isobutyl alcohol, etc.) and amides (e.g., dimethylformamide, dimethylacetamide, etc.) ), Ketones or keto alcohols (eg, acetone, diacetone alcohol, etc.), ethers (eg, tetrahydrofuran, dioxane, etc.), polyalkylene glycols (eg, polypropylene glycol, etc.), alkylene group containing 2 to 6 carbon atoms Alkylene glycols (eg, propylene glycol, butylene glycol, 1,2,6 hexanetriol, thiodiglycol, hexylene glycol, etc.), glycerin Lower alkyl ethers of polyhydric alcohols (ethylene glycol methyl ether, triethylene glycol monomethyl (or ethyl or butyl) ether,) and the like.

In the present invention, pigments and disperse dyes can be used as colorants. These pigments and disperse dyes are used by dispersing in a solvent that is appropriately selected and used as desired. Representative examples are described below, but the present invention is not limited to these. Preferred disperse dyes for the present invention include C.I. I. Disperse Yellow 3, 4, 5,
7, 9, 13, 24, 30, 33, 34, 42, 44,
49, 50, 51, 54, 56, 58, 60, 63, 6
4, 66, 68, 71, 74, 76, 79, 82, 8
3, 85, 86, 88, 90, 91, 93, 98, 9
9, 100, 104, 114, 116, 118, 11
9, 122, 124, 126, 135, 140, 14
1, 149, 160, 162, 163, 164, 16
5, 179, 180, 182, 183, 186, 19
2, 198, 199, 202, 204, 210, 21
1, 215, 216, 218, 224; I. Disperse Orange 1, 3, 5,
7, 11, 13, 17, 20, 21, 25, 29, 3
0, 31, 32, 33, 37, 38, 42, 43, 4
4, 45, 47, 48, 49, 50, 53, 54, 5
5, 56, 57, 58, 59, 61, 66, 71, 7
3, 76, 78, 80, 89, 90, 91, 93, 9
6, 97, 119, 127, 130, 139, 142; I. DisperseRed1,4,5,7,1
1, 12, 13, 15, 17, 27, 43, 44, 5
0, 52, 53, 54, 55, 56, 58, 59, 6
0, 65, 72, 73, 74, 75, 76, 78, 8
1, 82, 86, 88, 90, 91, 92, 93, 9
6, 103, 105, 106, 107, 108, 11
0, 111, 113, 117, 118, 121, 12
2, 126, 127, 128, 131, 132, 13
4, 135, 137, 143, 145, 146, 15
1, 152, 153, 154, 157, 159, 16
4, 167, 169, 177, 179, 181, 18
3, 184, 185, 188, 189, 190, 19
1, 192, 200, 201, 202, 203, 20
5, 206, 207, 210, 221, 224, 22
5,227,229,239,240,257,25
8, 277, 278, 279, 281, 288, 29
8, 302, 303, 310, 311, 312, 32
0, 324, 328; I. DisperseViolet1,4,8,2
3, 26, 27, 28, 31, 33, 35, 36, 3
8, 40, 43, 46, 48, 50, 51, 52, 5
6, 57, 59, 61, 63, 69, 77; I. Disperse Green 9; I. Disperse Brown 1, 2, 4, 9,
13, 19; I. DisperseBlue3, 7, 9, 14,
16, 19, 20, 26, 27, 35, 43, 44, 5
4, 55, 56, 58, 60, 62, 64, 71, 7
2, 73, 75, 79, 81, 82, 83, 87, 9
1, 93, 94, 95, 96, 102, 106, 10
8, 112, 113, 115, 118, 120, 12
2, 125, 128, 130, 139, 141, 14
2,143,146,148,149,153,15
4, 158, 165, 167, 171, 173, 17
4, 176, 181, 183, 185, 186, 18
7, 189, 197, 198, 200, 201, 20
5, 207, 211, 214, 224, 225, 25
7, 259, 267, 268, 270, 284, 28
5, 287, 288, 291, 293, 295, 29
7, 301, 315, 330, 333; I. Dis
perseBlack 1, 3, 10, 24; and the like.

The pigments preferred in the present invention include carbon black pigments (CI Pigment Bla).
ck7); I. Pigment Yellow 12, 13, 1
4, 16, 17, 73, 74, 75, 83, 108, 1
C. 09, 110, 180, 182; I. PigmentRed5, 7, 12, 112,
123, 168, 184, 202; I. PigmentBlue 1, 2, 3, 15:
3, 16, 22, 60; I. VatBlue 4, 60; In addition to the above, when red, green, blue, and intermediate colors are required, the following pigments are preferably used alone or in combination.

C. I. PigmentRed 209, 2
24, 177, 194; I. Pigment Orange 43; I. VatViolet3; I. PigmentViolet 19, 23, 3
7; I. Pigment Green 36, 7; I. Pigment Blue 15: 6; and the like.

The pigment and the disperse dye used in the ink of the present invention are mixed with a dispersant and other additives necessary for various desired purposes and dispersed by a disperser.

As the disperser, a conventionally known ball mill, sand mill, line mill, high-pressure homogenizer and the like can be used.

A surfactant is used as a dispersant. As the surfactant used in the present invention, any of cationic, anionic, amphoteric and nonionic can be used.

Examples of the cationic surfactant include aliphatic amine salts, aliphatic quaternary ammonium salts, benzalkonium salts, benzethonium chloride, pyridinium salts, and imidazolinium salts. Examples of the anionic surfactant include fatty acid soap, N-acyl-N-methylglycine salt, N-acyl-N-methyl-β-alanine salt, N-acylglutamate, acylated peptide, alkyl sulfonate, Alkyl benzene sulfonate, alkyl naphthalene sulfonate, dialkyl sulfosuccinate, alkyl sulfo acetate, α-olefin sulfonate, N-acylmethyltaurine, sulfated oil, higher alcohol sulfate, secondary higher alcohol Sulfate, alkyl ether sulfate, secondary higher alcohol ethoxy sulfate, polyoxyethylene alkylphenyl ether sulfate, monoglycol sulfate, fatty acid alkylolamide sulfate, alkyl ether phosphate, alkyl phosphate And the like. Examples of the amphoteric surfactant include a carboxybetaine type, a sulfobetaine type, an aminocarboxylate, and imidazolinium betaine.

Examples of the nonionic activator include polyoxyethylene secondary alcohol ether, polyoxyethylene alkylphenyl ether, polyoxyethylene sterol ether, polyoxyethylene lanolin derivative polyoxyethylene polyoxypropylene alkyl ether, and polyoxyethylene glycerin fatty acid. Esters, polyoxyethylene castor oil, hydrogenated castor oil, polyoxyethylene sorbitol fatty acid ester, polyethylene glycol fatty acid ester, fatty acid monoglyceride, polyglycerin fatty acid ester, sorbitan fatty acid ester, propylene glycol fatty acid ester, sucrose fatty acid ester, fatty acid alkanolamide, Polyoxyethylene fatty acid amide, polyoxyethylene alkylamine, alkylamine oxa De, acetylene glycol, acetylene alcohol, and the like.

In the ink of the present invention, a surfactant can be used to accelerate the penetration of the ink droplets after ejection into the medium. The surfactant that can be used is not limited as long as it has no adverse effect such as storage stability on the ink, and the same surfactant as that used as the above dispersant is used. .

In the present invention, an electric conductivity adjusting agent may be used. Examples of the electric conductivity adjusting agent include potassium chloride, ammonium chloride, sodium sulfate, and the like.
There are inorganic salts such as sodium nitrate and sodium chloride, and water-soluble amines such as triethanolamine.

In the ink of the present invention, ejection stability,
Depending on the purpose of printhead and ink cartridge compatibility, storage stability, image storability, and other performance improvements,
Further, a viscosity adjusting agent, a specific resistance adjusting agent, a film forming agent, an ultraviolet absorber, an antioxidant, a fading inhibitor, a rust inhibitor, a preservative, and the like can be added.

The ink of the present invention can be used for any on-demand type ink jet recording system. Examples of the on-demand type include an electro-mechanical conversion type (for example, a single cavity type, a double cavity type, a bender type, a piston type, a shared mode type, a shared wall type, etc.), and an electro-thermal conversion type (for example,
Specific examples include a thermal inkjet type, a bubble jet type, etc., an electrostatic suction type (eg, an electric field control type, a slit jet type, etc.), and a discharge type (eg, a spark jet type, etc.).

[0049]

EXAMPLES The present invention will now be described more specifically with reference to examples, but the present invention is not limited to these embodiments.

Example 1 Ink compositions No. 1 to No. 18 were prepared with the following configuration.

Compound Addition amount Dye (described in Table 1) 5.0% Proxel GXL (D) manufactured by Zeneca 0.1% High-boiling organic solvent (described in Tables 1 and 2) Ethylene glycol (described in Tables 1 and 2) EG) Ion-exchanged water described in Table 1 Remainder The number of ejection nozzles = 128, the nozzle diameter = 25 μm, the ejection frequency = 30 kHz, and the droplets were ejected, and the droplet speed was measured. The droplet volume at this time was 10 pL.

The structure of the head 1 of the piezo-type ink jet tester is as shown in FIG. FIG. 1B is a sectional view of the head 1 taken along line AA.

In FIG. 1A, a head 1 having five discharge nozzles is illustrated for explanation, but a head having 128 nozzles is used in the embodiment. Piezo element 2 for discharging ink droplets by displacement of piezo element
Are provided on the head corresponding to each ejection nozzle.
Further, a driver IC 3 for supplying a driving signal and a heating signal to the piezo element is arranged on the ink flow path (ink reservoir). Further, a thermistor 4 is provided on the discharge nozzle near the piezo element, and constitutes a temperature measuring means.

Continuous ejection is performed at a temperature of 24 ° C. and a humidity of 23%, and the driving voltage of the piezo element is changed to change the droplet speed to 8
m / s.

Thereafter, after the ejection was stopped for a certain period of time, the ejection was performed again, and the speed of the droplet ejected first after the re-ejection was measured. The droplet speed was determined from the time after the ejection and the moving distance by a stroboscope linked to the ejection. Table 2
The medium and high boiling organic solvents 1, 2, and 3 are referred to as HBSs 1, 2, and 3, respectively. A = EG + HBS1 + HBS2 / EG + HBS1 + HB
S2 + HBS3 B = EG / HBS1 + HBS2 + HBS3 C = EG / HBS1 + HBS2 + HBS3 / total amount of ink The same applies to Table 6 described later.

[0056]

[Table 1]

[0057]

[Table 2]

From Table 2, it can be seen that the ink of the present invention has a smaller decrease in the droplet velocity than the ink of the comparative example.

Example 2 Using ink No. 1 to No. 18, the number of ejection nozzles = 12
8. Discharge was performed using a piezo-type ink jet tester with a nozzle diameter of 22 μm and a discharge frequency of 30 kHz, and the droplet velocity was measured in the same manner as in Example 1. The droplet volume at this time was 7 pL.

[0060]

[Table 3]

From Table 3, it can be seen that the ink of the present invention has a smaller decrease in the droplet speed than the ink of the comparative example.

Example 3 The number of ejection nozzles = 12 using ink Nos.
8. Discharge was performed using a piezo-type ink jet tester having a nozzle diameter of 20 μm and a discharge frequency of 30 kHz, and the droplet velocity was measured in the same manner as in Example 1. The droplet volume at this time was 5 pL.

[0063]

[Table 4]

From Table 4, it can be seen that the ink of the present invention has a smaller decrease in the droplet speed than the ink of the comparative example.

Example 4 Inks No. 19 to No. 36 were manufactured with the following configuration.

Compound Amount Dye (described in Table 5) 5.0% High boiling organic solvent (described in Tables 5 and 6) Described in Tables 5 and 6 Formalin condensate of creosote oil sodium sulfonate (Kao Corporation) Demol C) 10% 2- (2-ethylhexyl) sodium sulfosuccinate 0.05% Nonylphenol ethylene oxide 10 mol adduct 1% Zeneca Proxel GXL (D) 0.1% Ion-exchanged water balance The above mixture has a diameter of 0. Using a ceramic bead of 0.5 mm, the mixture was dispersed for 5 hours at a rotation speed of 2500 rpm with a sand grinder manufactured by Imex.

Each ink composition having the above composition was prepared and evaluated in the same manner as in Example 1.

[0068]

[Table 5]

[0069]

[Table 6]

From Tables 5 and 6, it can be seen that the ink of the present invention has a lower drop velocity than the ink of the comparative example.

Example 5 Ink No. 19-No. 36, the number of discharge nozzles =
128, nozzle diameter = 22 μm, discharge frequency = 30 kHz
Is discharged by a piezo method ink jet tester,
The droplet speed was measured in the same manner as in Example 1. The droplet volume at this time was 7 pL.

[0072]

[Table 7]

From Table 7, it can be seen that the ink of the present invention shows less decrease in the droplet speed than the ink of the comparative example.

Example 6 Ink No. 19-No. 36, the number of discharge nozzles =
128, nozzle diameter = 20 μm, discharge frequency = 30 kHz
Is discharged by a piezo method ink jet tester,
The droplet speed was measured in the same manner as in Example 1. The droplet volume at this time was 5 pL.

[0075]

[Table 8]

From Table 8, it can be seen that the ink of the present invention has less decrease in the droplet speed than the ink of the comparative example.

[0077]

The ink jet recording liquid according to the present invention has excellent ejection stability even in a low humidity environment, so that it is not necessary to carry out preliminary ejection for a long time and has an effect of excellent image storability.

[Brief description of the drawings]

FIG. 1 is a schematic view showing an example of a head of a piezo-type inkjet tester used in the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Head 2 Piezo element 3 Driver IC 4 Thermistor

Claims (6)

[Claims] 1. An on-demand ink jet recording liquid containing at least a plurality of high-boiling organic solvents containing water, a colorant and ethylene glycol, wherein the amount of ethylene glycol, the amount of diethylene glycol monomethyl ether, the amount of triethylene glycol in the high-boiling organic solvent, An inkjet recording liquid, wherein the total amount of glycol monomethyl ether, diethylene glycol monoethyl ether and γ-butyrolactone is 80% or more. 2. An on-demand ink jet recording liquid containing at least a plurality of high-boiling organic solvents containing water, a coloring agent and ethylene glycol, wherein the amount of ethylene glycol, the amount of diethylene glycol monomethyl ether and the amount of γ- An ink jet recording liquid, wherein the total amount of butyrolactone is 80% or more. 3. An on-demand ink jet recording liquid containing at least a plurality of high-boiling organic solvents containing water, a colorant and ethylene glycol, wherein the sum of the amounts of ethylene glycol and γ-butyrolactone in the high-boiling organic solvent is reduced. 80% or more of an inkjet recording liquid. 4. An on-demand ink jet recording liquid containing at least a plurality of high-boiling organic solvents containing water, a colorant and ethylene glycol, wherein the total amount of ethylene glycol and diethylene glycol monomethyl ether in the high-boiling organic solvent is 80% or more of an inkjet recording liquid. 5. The high boiling organic solvent, wherein the proportion of ethylene glycol is 50% to 90%, and the content of the high boiling organic solvent is 20% to 60% in the ink jet recording liquid. The inkjet recording liquid according to any one of claims 1 to 4. 6. The method according to claim 1, wherein an ink jet apparatus having a minimum droplet volume of 10 pL or less is used.
6. The ink jet recording liquid according to any one of the above items 5.