JP3191881B2 - Water-based ink - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water-based ink, and more particularly, to a water-based ink excellent in dissolution stability and drying prevention effect and excellent in printing quality, particularly a water-based ink suitable for inkjet recording.

[0002]

2. Description of the Related Art Conventional ink jet printer inks are classified into so-called oil-based inks in which an oil-soluble dye is dissolved in an organic solvent, and so-called aqueous inks in which a water-soluble dye is dissolved in water. Oil-based inks are excellent in water resistance, but have problems such as safety and bleeding of odor on plain paper. Therefore, aqueous inks are often used for general ink jet recording.

[0003] Colorants used in aqueous inks include:
Pigments and dyes that can be dispersed or dissolved in water have been generally proposed, but ordinary ink jet recording methods are 10 to 20.
Since the ink is ejected from a fine nozzle of 0 microns, there is always a risk of nozzle clogging. Many of the coloring agents actually used are water-soluble dyes having excellent dissolution stability, among which anionic direct dyes and acid dyes are used. However, water-based ink evaporates water,
There is a disadvantage that nozzle clogging is likely to occur. In order to improve the above disadvantages, various anti-drying agents (wetting agents) have been proposed in the past.

That is, dimethyl sulfoxide; 1,3
-Dimethyl-2-pyrrolidinone; ethylene glycol,
Highly water-absorbing high-boiling water-soluble organic solvents such as polyhydric alcohols such as diethylene glycol, triethylene glycol, polyethylene glycol, polypropylene glycol, and glycerin; and pyrrolidones such as N-methyl-2-pyrrolidone have been generally proposed. Has been used for

In Japanese Patent Application Laid-Open No. 58-183768, an alkanolamine salt of a fatty acid is disclosed in Japanese Patent Application Laid-Open No. 58-877.
No. 0 discloses ethylenediamine having a specific structure,
JP-A-60-58478 discloses a polyethylene polyamine having a specific structure, disclosed in JP-A-63-215781.
Japanese Patent Application Publication No. JP-A-2005-64139 proposes an aqueous ink containing a polyamine compound and a phosphate compound as essential components.

[0006]

The above-mentioned anti-drying agent comprises:
To increase the drying prevention effect, the amount of the anti-drying agent increases, and the bleeding of the print becomes worse. Conversely, if the bleeding of the printing is reduced, the amount of the anti-drying agent decreases, and the anti-drying effect becomes worse. Had disadvantages. In view of the above, an object of the present invention is to provide an aqueous ink excellent in drying prevention effect, excellent in print quality, and excellent in dissolution stability, particularly, an aqueous ink suitable for inkjet recording.

[0007]

Means for Solving the Problems The present inventors have conducted intensive studies to solve the above-mentioned problems, and as a result, have reached the present invention.

[0008] The present invention relates to an aqueous ink containing water and a colorant, which comprises a salt comprising an amine and an acid having at least one hydroxyl group and an acidic group. is there.

The amine of the present invention is a compound having one or more primary, secondary, and tertiary amines in its chemical structure, and exhibits a solubility in water in a required compounding amount or more when combined with an acid. Any type is acceptable, but it is necessary to select the type and molecular weight depending on the dye to be combined.

Specifically, the following compounds are used. Amine 1 Triethanolamine Amine 2 Diethanolamine Amine 3 Monoethanolamine Amine 4 N-Methyl-diethanolamine Amine 5 N-Ethyl-diethanolamine Amine 6 Ethylenediamine Amine 7 Diethylenetriamine Amine 8 Triethylenetetramine Amine 9 Tetraethylenepentamine Amine 10 Polyethyleneimine Amine 11 Pentamethyldiethylenetriamine amine 12 tetramethylpropylenediamine amine 13 3 moles of ethylene oxide of tetraethylenepentamine
Propylene oxide 1 mol adduct Amine 14 Polyallylamine Amine 15 Polyamide polyamine epichlorohydrin

The acid of the present invention is an acid having one or more hydroxyl groups (hereinafter referred to as an acid), and any acid which exhibits a solubility in water of a necessary amount or more when combined with the above amine. However, it is necessary to select the type and molecular weight depending on the dye to be combined.

Specifically, the following compounds are used. Acid 1 glycolic acid acid 2 lactic acid 3 citric acid 4 citric acid 4 tartaric acid 5 glyceric acid 6 tropic acid 7 benzylic acid 8 ethylene oxide 2 mol adduct of lactic acid acid 9 p-hydroxybenzoic acid 10 glycerophosphoric acid

The salt of an amine and an acid according to the present invention can easily form a salt even if they are separately compounded in an ink. The amount of each salt is not specified, but 0.1% to 10%. The range is more preferable, and if possible, it is necessary to suppress the amount of addition so as not to impair the drying prevention effect in consideration of bleeding on recording paper. The ratio is alkaline when the amine is equal to or more than an equivalent, and acidic when the ratio is less than the above.Therefore, the pH may be set to an arbitrary value according to the dissolution stability of the colorant. An arbitrary pH may be set with another pH adjuster. Also, a plurality of amines and acids may be used in combination,
Compounds other than the above compound examples can also be used, and when the number of nitrogen atoms in the amine is large, there is an advantage that the water resistance of the printed matter is improved.

The aqueous ink according to the present invention containing a salt comprising an amine and an acid having at least one hydroxyl group and an acidic group has excellent drying prevention effect, excellent printing quality, and excellent dissolution stability. Are better.

An aqueous ink composition in which the salt comprises an amine and an oxyacid having one or more hydroxyl groups and carboxyl groups as substituents exhibits particularly excellent effects.

The aqueous ink composition in which the amine is an alkanolamine or an ethylene oxide derivative thereof has a particularly remarkable improvement effect.

The aqueous ink composition in which the oxyacid is glycolic acid, lactic acid or glyceric acid has a particularly remarkable improvement effect.

Accordingly, when the aqueous ink of the present invention is used in an ink jet printer, an excellent drying prevention effect and printing quality can be obtained, and an excellent dissolution stability can be obtained.

In the present invention, another water-soluble organic solvent may be used in combination. Examples of the water-soluble organic solvent include methyl ether, ethyl ether, isopropyl ether, n-propyl ether and isobutyl ether of ethylene glycol or propylene glycol. Glycol ethers such as n-butyl ether, substituted or unsubstituted phenyl ether, dimethyl ether and diethyl ether; dimethyl sulfoxide; polyhydric alcohols such as ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, polypropylene glycol and glycerin; ethanol , Lower alcohols such as isopropyl alcohol; pyrrolidones such as N-methyl-2-pyrrolidone; and the like.
They can be used alone or in combination. However, the water-soluble organic solvent that can be used in the present invention is not limited to these.

As the coloring agent, general dyes and pigments can be used, and particularly, a water-soluble dye having excellent dissolution stability is preferable, and any water-soluble dye can be used. , Basic dyes, direct dyes, reactive dyes, disperse dyes, food colorants, fluorescent brighteners and the like.

Specifically, examples of the acid dye include, for example,
C. I. Acid black 1,2,7,16,17,
24, 26, 28, 31, 41, 48, 52, 58, 6
0, 63, 94, 107, 109, 112, 118, 1
19, 121, 122, 131, 155, 156;
I. Acid Yellow 1,3,4,7,11,12,
13, 14, 17, 18, 19, 23, 25, 29, 3
4,36,38,40,41,42,44,49,5
3,55,59,61,71,72,76,78,7
9, 99, 111, 114, 116, 122, 135,
142, 161, 172; C.I. I. Acid orange 7, 8, 10, 19, 20, 24, 28, 33, 41,
45, 51, 56, 64; I. Acid Red 1,4,6,8,13,14,15,18,19,2
1,26,27,30,32,34,35,37,4
0, 42, 51, 52, 54, 57, 80, 82, 8
3,85,87,88,89,92,94,97,10
6,108,110,111,114,115,11
9,129,131,133,134,135,14
3,144,152,154,155,172,17
6,180,184,186,187,249,25
4,256,289,317,318; C.I. I. Acid Violet 7, 11, 15, 34, 35, 41,
43, 49, 51, 75; I. Acid Blue 1,7,9,15,22,23,25,27,29,4
0, 41, 43, 45, 49, 51, 53, 55, 5
6,59,62,78,80,81,83,90,9
2,93,102,104,111,113,117,
120, 124, 126, 138, 145, 167, 1
71,175,183,229,234,236,24
9; I. Acid Green 3,9,12,16,1
9, 20, 25, 27, 41, 44; I. Acid Brown 4, 14 and the like.

Examples of the basic dye include C.I. I. Basic black 2, 8; I. Basic yellow 1, 2, 11, 12, 14, 21, 32, 36;
I. Basic orange 2,15,21,22; C.I.
I. Basic Red 1,2,9,12,13,3
7; I. Basic Violet 1,3,7,1
0, 14; I. Basic Blue 1,3,5
7, 9, 24, 25, 26, 28, 29; I. Basic green 1, 4; I. Basic Brown 1, 12 and the like.

Examples of the direct dye include C.I. I. Direct Black 2,4,9,11,14,17,1
9, 22, 27, 32, 36, 38, 41, 48, 4
9,51,56,62,71,74,75,77,7
8, 80, 105, 106, 107, 108, 112,
113, 117, 132, 146, 154, 168, 1
71, 194; I. Direct yellow 1,2,
4, 8, 11, 12, 24, 26, 27, 28, 33,
34, 39, 41, 42, 44, 48, 502, 51,
58, 72, 85, 86, 87, 88, 98, 100,
110, 127, 135, 141, 142, 144;
C. I. Direct orange 6,8,10,26,2
9, 41, 49, 51, 102; I. direct
Red 1, 2, 4, 8, 9, 11, 13, 152, 1
7, 20, 23, 24, 28, 31, 33, 37, 3
9,44,46,47,48,51,59,62,6
3,73,75,77,80,81,83,84,8
5,87,89,90,94,95,99,101,1
08,110,145,189,197,220,22
4,2252,226,227,230,250,25
4,256,257; C.I. I. Direct violet 1,7,9,12,35,48,51,90,94;
C. I. Direct Blue 1,2,6,8,15,2
2,25,34,69,70,71,72,75,7
6,78,80,81,82,83,86,90,9
8, 106, 108, 110, 120, 123, 15
8,163,165,192,193,194,19
5,196,199,200,201,202,20
3,207,218,236,237,239,24
6,258,287; C.I. I. Direct green 1, 6, 8, 28, 33, 37, 63, 64; I.
Direct Brown 1A, 2, 6, 25, 27, 4
4,58,95,100,101,106,112,1
73, 194, 195, 209, 210, 211 and the like.

As the reactive dye, for example, C.I. I. Reactive Black 1,3,5,6,8,12,1
4; I. Reactive Yellow 1,2,3,1
3, 14, 15, 17; I. Reactive orange 2,5,7,16,20,24; C.I. I. Reactive Red 6,7,11,12,15,17,21,2
3,24,35,36,42,63,66,84,18
4; I. Reactive Violet 2,4,5
8, 9; I. Reactive Blue 2,5,7,1
2,13,14,15,17,18,19,20,2
1, 25, 27, 28, 37, 38, 40, 41;
I. Reactive green 5, 7; I. Reactive Brown 1, 7, 16 and the like.

Examples of food colors include C.I. I. Food black 1, 2; I. Food yellow 2,
4,5; C.I. I. Food Red 2,3,7,9,1
4,52,87,92,94,102,104,10
5,106; I. Food Violet 2: C.I.
I. Food blue 1, 2; I. Food Green 2, 3 and the like.

Other water-soluble dyes include, for example, "Kayaset Black Nine A", "Direct Deep Black XA" and "Direct Special Black AXN" manufactured by Nippon Kayaku Co., Ltd .; Special Black SP Liquid "," Biscript "
"Black SP Liquid", "Rebasel Turquoise Blue KS-6GLL", "Pyramine";"JI.BK-2","JI.BK-3" manufactured by Sumitomo Chemical Co., Ltd .; "JP-K81L" manufactured by Orient Chemical Co., Ltd. "," JP-K127
L "," JPK-139 "; I. Florescent
Brightening Agent 14, 22, 24, 3
2,84,85,86,87,90,134,166,
167, 169, 175, 176, 177 and the like.

These coloring agents can be used alone or in combination of two or more. The amount used in the ink composition is 0.1 to 10%.
A range of weight percent is desirable.

The water is preferably of a purity higher than that of ion-exchanged water in order to stabilize the dissolution of the dye and prevent nozzle clogging due to heavy metal ions. The amounts of water, water-soluble dye, and water-soluble organic solvent to be added can be appropriately determined in consideration of the required characteristics of the ink and the required physical properties.

Further, additives such as an antiseptic / antifungal agent, a heavy metal sequestering agent and a pH adjuster can be used in the ink jet recording ink of the present invention.

[0030]

The salt of an amine and an acid according to the present invention not only exhibits an extremely strong hygroscopicity and produces an effect of preventing drying, but also
Unlike other inorganic salts, the salting out effect on the dye is small,
It is believed that the dissolution stability is not impaired.

[0031]

Next, the present invention will be described more specifically with reference to examples and comparative examples. The parts in the text are based on weight.

Example 1 Salt of amine 1 and acid 2 3.0 parts Isopropyl alcohol 5.0 parts Diethylene glycol 5.0 parts C.I. I. Direct Black 192.0 parts Ion-exchanged water Remainder After the above components were mixed and dissolved, the mixture was filtered through a membrane filter having a pore size of 0.5 µm to obtain an aqueous ink of the present invention.

The obtained aqueous ink did not generate any precipitate even after being left for 6 months. Further, the ink jet printer was mounted on a drop-on-demand type ink jet printer using piezo, and continuous printing and reprinting were performed after standing for two weeks. The ejection stability was good and the printing quality was good.

Example 2 Amine 4 and acid 1 salt 4.0 parts C.I. I. Food Black 2 3.0 parts Ion-exchange water Remainder After the above components were mixed and dissolved, the mixture was filtered through a membrane filter having a pore size of 0.5 μm to obtain an aqueous ink of the present invention.

The obtained aqueous ink did not generate any precipitate even after being left for 6 months. The ink jet printer was mounted on a thermal jet type ink jet printer utilizing thermal energy for recording, and continuous printing and reprinting were performed after standing for 2 weeks. The ejection stability was good and the printing quality was good.

Example 3 Salt of amine 11 and acid 3 4.2 parts Diethylene glycol 10.0 parts C.I. I. Direct Blue 199 2.0 parts Ion-exchanged water Remainder After the above components were mixed and dissolved, the remaining components were additionally dissolved and filtered through a membrane filter having a pore size of 0.5 μm to obtain an aqueous ink of the present invention.

The obtained aqueous ink did not generate any precipitate even after standing for 6 months. Further, the ink jet printer was mounted on a continuous type ink jet printer, and continuous printing and reprinting were performed after standing for 2 weeks. The ejection stability was good and the printing quality was good.

COMPARATIVE EXAMPLE 1-1 Each component using acid 2 instead of the salt of amine 1 and acid 2 of Example 1 was mixed and dissolved, and the mixture was filtered through a membrane filter having a pore size of 0.5 μm to obtain an aqueous ink. Was.

The resulting aqueous ink had a slight amount of precipitate after standing for 6 months. The ink jet printer was mounted on a drop-on-demand type ink jet printer using piezo, and continuous printing was performed, but the ejection stability was good. However, two weeks after the cap was removed, reprinting revealed that nozzle clogging had occurred.

Comparative Example 1-2 Each component using amine 1 in place of the salt of amine 1 and acid 2 of Example 1 was mixed and dissolved, and the mixture was filtered through a membrane filter having a pore size of 0.5 μm to obtain an aqueous ink. Was.

The obtained aqueous ink did not generate any precipitate even after being left for 6 months. The ink jet printer was mounted on a drop-on-demand type inkjet printer using piezo, and continuous printing was performed. However, the ejection stability was good. However, two weeks after the cap was removed, reprinting revealed that nozzle clogging had occurred.

Comparative Example 2-1 The components using acid 1 in place of the salt of amine 4 and acid 1 of Example 2 were mixed and dissolved, and the mixture was filtered through a membrane filter having a pore size of 0.5 μm to obtain an aqueous ink. Was.

The resulting aqueous ink had a slight amount of precipitate after standing for 6 months. The ink jet printer was mounted on a thermal jet type ink jet printer utilizing thermal energy for recording, and continuous printing was performed, but the ejection stability was good. However, two weeks after the cap was removed, reprinting revealed that nozzle clogging had occurred.

Comparative Example 2-2 The components using amine 4 in place of amine 4 and acid 1 of Example 2 were mixed and dissolved, and the mixture was filtered through a membrane filter having a pore size of 0.5 μm to obtain an aqueous ink. Was.

The obtained aqueous ink did not generate any precipitate even after being left for 6 months. The ink jet printer was mounted on a thermal jet type ink jet printer utilizing thermal energy for recording, and continuous printing was performed. The ejection stability was good. However, two weeks after the cap was removed, reprinting revealed that nozzle clogging had occurred.

Comparative Example 3-1 The components using the acid 3 in place of the amine 11 and the acid 3 of Example 3 were mixed and dissolved, and the mixture was filtered through a membrane filter having a pore size of 0.5 μm to obtain an aqueous ink.

The resulting aqueous ink had a slight amount of precipitate after standing for 6 months. The ink jet printer was mounted on a continuous type ink jet printer, and continuous printing was performed, but the ejection stability was good. However, two weeks after the cap was removed, reprinting revealed that nozzle clogging had occurred.

Comparative Example 3-2 The respective components of Example 3 using amine 11 in place of acid 3 were mixed and dissolved, followed by filtration through a membrane filter having a pore size of 0.5 μm to obtain an aqueous ink.

The obtained aqueous ink did not generate any precipitate even after being left for 6 months. The ink jet printer was mounted on a continuous type ink jet printer, and continuous printing was performed. The ejection stability was good. However, two weeks after the cap was removed, reprinting revealed that nozzle clogging had occurred.

The ink of the present invention can be used not only as a jet printer but also as an aqueous ink for any recording system.

[0051]

The aqueous ink according to the present invention containing a salt composed of an amine and an acid having at least one hydroxyl group and an acidic group is excellent in drying prevention effect, excellent in printing quality, and more stable in dissolution. Excellent in nature.

Therefore, when the aqueous ink of the present invention is used in an ink jet printer or the like, an excellent drying prevention effect and printing quality can be obtained, and an excellent dissolution stability can be obtained.

Continuation of front page (58) Field surveyed (Int.Cl. ⁷ , DB name) C09D 11/00-11/20

Claims (3)

(57) [Claims] 1. An aqueous ink containing water and a colorant, the aqueous ink further comprising an amine and an oxyacid.
A salt as an anti-drying agent and the oxyacid
Lactic acid, or lactic acid, or glyceric acid
Aqueous ink characterized. 2. The amine is an alkanolamine.
The aqueous ink according to claim 1, wherein 3. The method according to claim 1, wherein
The aqueous ink contains a dye as a colorant, and
The dye is an anionic direct dye or an acid dye
A water-based ink, characterized in that: