JPH0892514A - Water-based ink for ink jet recording - Google Patents

Abstract

PURPOSE: To obtain the subject ink, containing a pigment and a compound having a specific structure, less apt to clog a nozzle without scorching the ink on the head of an ink jet printer and capable of realizing prints having a high line marker properties. CONSTITUTION: This water-based ink for ink jet recording contains (A) a pigment (e.g. carbon black) and (B) a compound of the formula [R1 and R2 are each hydroxy, an alkoxy, etc.; (x) is 1-4] (preferably tetrabromophthalic anhydride, tetrabromophthalic acid diol, etc.). Furthermore, the component (B) is preferably kneaded in the component (A), etc., to coat the surface of the component (A) with the component (B) in preparing the ink. The blending composition of the ink based on the total amount of the ink is preferably regulated so as to provide 0.7-7wt.% component (A), 0.1-10wt.% component (B), 60-95wt.% water and 0.5-20wt.% other components such as a wetting agent or a chelating agent.

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 for ink jet recording, and more specifically, it is a water for ink jet recording capable of realizing printing that does not scorched on a printer head of an ink jet printer and does not cause clogging. The present invention relates to a system ink and an inkjet recording method using the same.

[0002]

2. Description of the Related Art The ink jet recording system is a recording system in which characters and images are obtained by directly ejecting and adhering ink droplets from a very fine nozzle onto a recording member. According to this method, not only has the advantage that the device used is low in noise and has good operability, but it also has the advantage that plain color can be used and plain paper can be used as a recording member.
Widely used in recent years. As the ink ejection method,
A piezoelectric type using a piezoelectric element for a printer head and a thermal jet type using a heater for a heating resistance element are widely used as personal printers.

[0003]

In order to prevent the ink from being clogged in the nozzle, a water-soluble dye which is usually soluble in water is used for the ink used in the ink jet printer. By using a water-soluble dye, the ink is less likely to be clogged in the nozzle, but on the other hand, the problem of poor water resistance, and especially in the case of the thermal jet type, the dye is oxidized by the excessive heat in the printer head There was a problem that it was easy to burn.

In the thermal jet type, a heater of a heating resistance element is incorporated in the printer head, the ink is boiled by its thermal energy, and the ink is ejected as droplets by the pressure of bubbles, so that the ink is used as a heater. When heated and boiled above, the dye in the ink may be altered or decomposed, and insoluble matter may be deposited on the printer head and cause clogging. Therefore, the composition of the ink is important in order to prevent such clogging.

In order to prevent the ink from sticking to the printer head, the ink may contain an organic sulfonate (Japanese Patent Laid-Open No. 4-227669), or the dye may have a special structure (Japanese Patent Laid-Open No. 4-27469). No. 226175),
The ink may contain a bile salt (Japanese Patent Laid-Open No. 5-1948).
No. 88), but it is not sufficient.

When a pigment is used as the ink, AB or BA is used in order to improve the stability of the pigment.
A pigment is dispersed in a B block copolymer (JP-A-5-179183), a dye containing a sulfonic acid or a sulfonate group is contained in the ink (JP-A-5-247391), the surface of the pigment Although many proposals have been made such that a polymerized vinyl aromatic salt is bonded to the above (JP-A-4-234467), these proposals are still not sufficient.

Further, no product satisfying these complex requirements in a balanced manner has been obtained.

Accordingly, an object of the present invention is to provide a water-based ink for ink jet recording and a ink jet recording method using the same, which can realize printing that does not scorched on a printer head of an ink jet printer and does not cause clogging. is there.

[0009]

As a result of earnest research, the inventors of the present invention have found that by using a pigment in combination with a specific compound in a water-based ink for ink jet recording, the ink sticks to a printer head and nozzles. It was found that it is possible to prevent the clogging of.

The present invention has been made based on the above findings, and provides a water-based ink for ink jet recording characterized by containing a pigment and a compound represented by the following general formula (I). The above-mentioned object is achieved.

[0011]

[Chemical 2]

Further, the present invention is an ink jet recording method using the above water base ink for ink jet recording of the present invention, wherein thermal ink is used to record the above water base ink for ink jet recording from the nozzle as ink droplets. Provided is a device characterized in that a member is ejected to perform recording.

The aqueous ink for ink jet recording of the present invention will be described in detail below.

In the water-based ink for ink jet recording of the present invention, the reason why the ink can be prevented from being scorched on the printer head and clogging of the nozzles is not always clear by including the pigment and the compound. However, it is estimated as follows. The ink is exposed to high temperatures of about 700 ° C. in the printer head. The pigment generally becomes active when exposed to high temperature, but in the ink of the present invention, the pigment is present in the medium water in such a state that its surface is coated with the above compound. Since the compound has excellent heat resistance, the pigment coated with the compound is protected from heat by the compound. As a result, it is considered that the sticking to the printer head can be suppressed. Therefore, even if the above compound is used in combination with a coloring agent other than the pigment, such as a dye, the surface of the dye is not protected by the compound, and the effect of preventing the ink from sticking to the printer head cannot be expected. At the same time, it is considered that the above compound also has an action as a dispersant for the pigment. As described above, in the present invention, by using the pigment and the above compound in combination, an excellent effect which cannot be obtained by the conventional inkjet ink is exhibited.

The compound contained in the aqueous ink for ink jet recording of the present invention is represented by the above general formula (I). In the general formula (I), R ₁ and R ₂
Is an alkylene oxide adduct of each hydroxy group, the alkylene oxide is preferably a lower alkylene oxide such as ethylene oxide or propylene oxide. The alkylene oxide adduct may be a monoalkylene oxide adduct in which one alkylene oxide is added, or a polyalkylene oxide adduct in which two or more alkylene oxides are added. In the general formula (I), M
Examples of the alkali metal ion represented by ⁺ include sodium ion and potassium ion. In the present invention, the compounds represented by the general formula (I) may be used alone or in combination of two or more. Particularly preferred compounds in the present invention are the following (II),
It is a compound represented by (III), (IV) and (V). For example, Great Lake Chem. Corp. PHT4 (tetrabromophthalic anhydride), PHT4-
DIOL (Tetrabromophthalic anhydride diol), FR
-756 (tetrabromophthalic acid disodium salt) or the like can be used.

[0016]

[Chemical 3]

[0017]

[Chemical 4]

[0018]

[Chemical 5]

[0019]

[Chemical 6]

Any pigment can be used as the pigment to be contained in the water-based ink for ink jet recording of the present invention. For example, carbon black; C.I. I.
Pigment Yellow 1, 5, 12, 14, 17, 2
4, 42, 53, 83, 95, 97, 98 and 100;
C. I. Pigment Red 1, 3, 4, 5, 17, 2
2, 31, 48, 49, 53, 63, 64, 88 and 1
01; C.I. I. Pigment Blue 1, 15, 16, 2
7, 28, 29, 56, 60 and 63; C.I. I. Pigment Black 1, 7 and 11; and the like can be used. The blending amount is not particularly limited, but 0.5 to 10% is preferable.

The water-based ink for ink jet recording of the present invention contains water as a medium and contains a pigment and the above-mentioned compound, and in addition to various conventionally known additives, for example, wetting agents such as polyhydric alcohols and antifungal agents. Agents and / or chelating agents may be further added. Examples of the wetting agent include polyhydric alcohols such as ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, glycerin, diethylene glycol diethyl ether, and diethylene glycol mono-n-butyl ether, and their ethers, acetates, N-methyl-
One or more nitrogen-containing compounds such as 2-pyrrolidone and 1,3-dimethylimidazolidinone can be used.

The composition of the aqueous ink for ink jet recording of the present invention is not particularly limited, but generally 0.5 to 10% by weight of the pigment and 0.01 to 15% by weight of the above compound based on the total weight of the ink. 50 to 98% by weight of water and 0.1 to 30% by weight of other components, preferably 0.7 to 7% by weight of pigment, 0.1 to 10% by weight of the above compound, and 60% of water. ~ 95% by weight, other components 0.5-2
0% by weight. The weight ratio of the pigment to the compound is generally 10: 1 to 1: 5, preferably 5: 1.
~ 1: 3.

There is no particular limitation on the method for preparing the ink jet recording water-based ink of the present invention by mixing the above-mentioned components, and a conventionally known apparatus such as a ball mill, a sand mill, an attritor, a basket mill or a roll mill is used. Can be mixed. When preparing the ink, it is preferable to carry out a surface treatment such as kneading the above compound into the pigment. The method of surface treatment in this case is not particularly limited, but it is desirable to knead the pigment and the above compound before preparing the ink. For example, it is possible to obtain a surface-treated product by adding only a pigment and the above compound or a small amount of water thereto and heat-treating with a kneader. By carrying out such a treatment, the surface of the pigment is sufficiently covered with the above compound and further protected from heat.

The water base ink for ink jet recording of the present invention can be used in any printer as long as it is a printer using an ink jet recording system. For example, a printer of a piezoelectric recording method using a piezoelectric element in a printer head, and The printer head can be used in any printer of a thermal jet recording method that uses heat energy of a heater of a heating resistance element or the like.
In particular, the ink jet recording ink of the present invention is preferably used in a thermal jet recording method in which thermal energy is used to eject ink droplets from a nozzle onto a recording member to perform recording, and the thermal energy is heat resistance. The element heater is preferably used.

[0025]

EXAMPLES The effectiveness of the present invention will be illustrated by the following examples, but the present invention is not limited to these examples. In the following examples, parts represent parts by weight unless otherwise specified.

[Example 1] carbon black; 5 parts; compound represented by (II); 5 parts; diethylene glycol; 5 parts; water; 85 parts; and carbon black described above and a compound represented by (II) Water 5
The resulting mixture was heated to 60 ° C. with a kneader and kneaded for 2 hours, and then the kneaded product, diethylene glycol and the remaining water were mixed and dispersed for 2 hours using a 3-roll mill to form a coating material. The resulting dispersion was filtered through a 5 micron filter to remove dust and coarse particles to obtain an ink. When this ink was used for printing with a commercially available Canon Micro Bubble Jet Printer (BJ-550), the results shown in Table 1 were obtained. It should be noted that in Table 1, the charring of the printer head was judged by observing the charring of the printer head with a microscope after applying 5 million pulses. In the clogging test, the ink was left in an environment of 35 ° C. and 85% RH for 3 months, and then the clogging of the ink was printed with a commercially available Canon Micro Bubble Jet Printer (BJ-550) and a nozzle microscope. It was judged by observation.

[Example 2] C. I. Pigment Blue 15; 5 parts. Compound represented by (III); 5 parts. Glycerin; 4 parts. Water; 86 parts. The above components were made into paint by the same production method as in Example 1. The resulting dispersion was filtered through a 5 micron filter to remove dust and coarse particles to obtain an ink.
When this ink was used to print on a commercially available Canon Micro Bubble Jet Printer (BJ-550),
The results shown in Table 1 were obtained.

Comparative Example 1 C.I. I. Solvent Black 3 (dye); 6 parts-Compound represented by (III); 6 parts-Glycerin; 6 parts-Water; 82 parts The above components were made into paint by the same production method as in Example 1. . The resulting dispersion was filtered through a 5 micron filter to remove dust and coarse particles to obtain an ink.
When this ink was used to print on a commercially available Canon Micro Bubble Jet Printer (BJ-550),
The results shown in Table 1 were obtained.

Comparative Example 2 C.I. I. Pigment Red 3; 5 parts; Phthalic Anhydride; 5 parts; Glycerin; 4 parts; Water; 82 parts The above components were made into paint by the same production method as in Example 1. The resulting dispersion was filtered through a 5 micron filter to remove dust and coarse particles to obtain an ink.
When this ink was used to print on a commercially available Canon Micro Bubble Jet Printer (BJ-550),
The results shown in Table 1 were obtained.

[0030]

[Table 1]

As is clear from the results shown in Table 1, the water-based ink for ink jet recording of the present invention realizes printing that does not scorched on the printer head and does not cause nozzle clogging. To the end. In particular, the ink jet recording water-based ink of the present invention exhibits excellent effects when printed using a thermal jet ink jet printer.

[0032]

According to the present invention, there is provided a water-based ink for ink jet recording which does not scorched on the printer head of an ink jet printer, does not easily clog nozzles, and can realize printing with high line marker property.
In addition, according to the present invention, such an aqueous ink, particularly,
Provided is an ink jet recording method capable of preventing the ink from sticking to the printer head due to excessive heat when used in a thermal jet system utilizing thermal energy of a heater of a heating resistance element.

Claims (4)

[Claims] 1. A water-based ink for inkjet recording comprising a pigment and a compound represented by the following general formula (I). [Chemical 1] 2. The water-based ink for ink jet recording according to claim 1, wherein the pigment is surface-treated with the compound. 3. An ink jet recording method, wherein thermal ink is used to eject the aqueous ink for ink jet recording according to claim 1 or 2 as an ink droplet from a nozzle to a recording member to perform recording. . 4. The ink jet recording method according to claim 3, wherein a heater of a heating resistance element is used as the heat energy.