TWI484003B - Black inkjet ink composition - Google Patents

Description

Black inkjet ink composition

The present invention relates to a black ink jet ink composition, and more particularly to a black ink jet ink composition containing a polyvalent water soluble metal salt.

Inkjet printing technology is a non-impact printing technology, and its technical characteristics include: need to provide sharp, non-feathering images with good washing fastness (water) -fastness), light-fastness, optical density, fast drying and storage stability, good print fluency, non-clogging and other features.

In general, it is limited that the nozzle needs to be heated or pressurized to squeeze the ink out of the ink chamber, so the ink required for the ink must have low-salt or even salt-free. The characteristic is that it does not cause the accumulation of inorganic salts on the heating or pressing elements of the nozzle with long-term printing, and finally results in fouling of the heating or pressing elements or the generation of plugs on the nozzles. What is more, if the pH of the ink is too acidic, the polymer between the components of the bonding nozzle may be deformed, resulting in a drop in ink jet quality. Therefore, in the purification of the coloring material, the salt which is precipitated by the combination of the cation and the cation is deliberately removed. For example, calcium, magnesium, iron and other cations and chloride ions, sulfate Anions such as ions are used to avoid corrosion defects such as nozzles, salt precipitation, and nozzle clogging.

However, when the ink compositions are actually applied, it is more necessary to consider factors such as the amount of the ink composition on the paper and the printing strength. Those skilled in the art have hitherto been eager to find an ink composition that effectively reduces the amount of colorant and maintains high printing strength. In other words, the present invention provides an economical black inkjet ink composition.

Therefore, it is desirable to provide an ink composition which has an effect of reducing the amount of toner used and obtaining a higher printing strength.

SUMMARY OF THE INVENTION The main object of the present invention is to provide a black ink jet ink composition which can adjust the composition and content of the composition to obtain an ink composition which has a reduced amount of coloring material and a higher printing strength.

In order to achieve the above object, the present invention provides a black inkjet ink composition comprising: (A) 3 to 10% by weight of a black colorant, wherein the black colorant is a carbon having a carboxyl group and a hydroxyl group on the surface (B) 0.1% by weight to 20% by weight of the humectant; (C) 0.01% by weight to 0.3% by weight of the metal salt, wherein the metal salt is a divalent metal salt, a trivalent metal salt, or a combination thereof. And the solubility of the metal salt in water is 0.1 mole/L or more; and (D) the balance solvent.

When inkjet ink is printed on a substrate such as paper, when the amount of toner used rises to a certain extent, the strength of the ink does not increase with synchronization; excessive coloring not only causes waste, but also recycles the back end paper. Decolorization and deinking result in greater load and even increase the cost of recycled paper. Here, the above-described black ink jet ink composition of the present invention can be improved by selecting an appropriate additive. Therefore, as long as the strength of the black inkjet ink composition can be effectively improved, the ink of the low coloring amount can be obtained with the same strength as the high coloring material. At the same time, in order to make the ink have good ink-jet characteristics, the present invention must have a humectant at the same time to prevent evaporation of water of the ink. The characteristics and types of the humectant selected for use are not particularly limited in the present invention. For example, in one aspect of the invention, the humectant may comprise more than one compound suitable as a humectant, and the individual compounds as the humectant may have a molecular weight of from 80 to 300 g/mole. Preferably, the humectant of the black inkjet ink composition of the present invention may be a C _3-15 polyol, a C _5-15 ether alcohol, or a combination thereof. Preferably, in another aspect of the present invention, the humectant of the black inkjet ink composition may be a C _3-10 polyol, a C _5-10 ether alcohol, or a combination thereof, but the invention is not particularly This is limited to this. In detail, the C _3-15 polyol may be a C _3-15 diol or a C _3-15 triol; and the C _5-15 ether alcohol may be a C _5-15 diol ether, and the invention Not limited to this. Here, examples of the C _3-15 diol and the C _3-15 triol may include ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, tetraethylene glycol, and Glycol, polyethylene glycol, polypropylene glycol, 1,5-pentanediol, 1,6-hexanediol, glycerol, 1,2,6-hexanetriol, 1,2,4-butanetriol 1,2,3-butanetriol, etc.; examples of the C _5-15 glycol ether may include ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol single Ether, diethylene glycol monobutyl ether, triethylene glycol monobutyl ether, tetraethylene glycol monomethyl ether, propylene glycol monoethyl ether, etc., but the present invention is not limited thereto. In other words, as long as the black inkjet ink composition can have the above-described effect of reducing feathering, the humectant can include one or more different levels of compounds. For example, in one aspect of the invention, the humectant can include from 0.1 weight percent to 5 weight percent C _3-15 polyol, and from 5 weight percent to 15 weight percent C _5-15 ether alcohol. Preferably, in one aspect of the invention, the humectant may comprise from 1 to 3 weight percent dipropylene glycol, from 0.1 weight percent to 1 weight percent glycerol, and from 5 weight percent to 15 weight percent Triethylene glycol monobutyl ether. More preferably, in one embodiment of the present invention, the humectant may include 2.5 weight percent dipropylene glycol, 0.5 weight percent glycerol, and 10 weight percent triethylene glycol monobutyl ether, but the present invention Not limited to this.

In the above black inkjet ink composition of the present invention, when the black inkjet ink composition is printed on a substrate, as the solvent evaporates, the concentration of the metal salt contained therein increases, causing the black colorant to precipitate and generate Laking, which in turn enhances the printing strength of the black inkjet ink composition of the present invention. Accordingly, in the present invention, the type of the metal salt is not particularly limited in the present invention as long as the effect of the precipitation of the black coloring material to the lake is obtained. For example, in one aspect of the invention, the metal salt can be a magnesium salt, a calcium salt, a copper salt, a zinc salt, an aluminum salt, an iron salt, or a combination thereof. Preferably, in one embodiment of the present invention, the metal salt may be magnesium chloride, magnesium nitrate, magnesium acetate, calcium chloride, calcium nitrate, calcium acetate, copper chloride, copper nitrate, copper acetate, zinc chloride. Zinc nitrate, zinc acetate, aluminum chloride, aluminum nitrate, iron chloride, iron nitrate, or a combination thereof, but the invention is not limited thereto. In addition, the present invention does not limit the type of the above metal salt as long as the printing intensity of the black inkjet ink composition can be improved, for example, it can be a waterless type, a hydrated form containing water of crystallization, or a mixture thereof. Preferably, in one aspect of the invention, the metal salt may be a hydrated form containing water of crystallization, but the invention is not limited thereto. Furthermore, as long as the black inkjet ink composition can be controlled to produce a lake on the substrate without changing its physical properties to a black inkjet ink composition, those skilled in the art can be within the above concentration range. The concentration of the metal salt is adjusted depending on the characteristics of the desired black inkjet ink composition, and the present invention is not particularly limited thereto. Preferably, in one aspect of the invention, the concentration of the metal salt may range from 0.01 weight percent to 0.5 weight percent. In another aspect of the invention, the concentration of the metal salt can range from 0.05 weight percent to 0.2 weight percent. More preferably, in a specific aspect of the invention, the concentration of the metal salt may be from 0.05% by weight to 0.1% by weight, but the invention is not limited thereto.

Accordingly, by adding an appropriate amount of the metal salt, when the black inkjet ink composition is printed on the substrate, the precipitation of the black color material contained therein can be accelerated, thereby improving the printing of the black inkjet ink composition. The effect of strength.

The black inkjet ink composition of the present invention described above is not particularly limited to the black colorant as long as it can be used in the black inkjet ink composition of the present invention without causing defects such as precipitation and discoloration of the ink composition. Characteristics and types. For example, the black colorant may be a conventional carbon black (color material 7), such as furnace black, lamp black, acetylene black, channel black (channel black). )Wait. In addition, as long as the effect of uniformly dispersing the black colorant can be achieved, those skilled in the art can also modify the black color material to have a carbonyl on the surface by any conventional means. The invention is not limited thereto, and the carboxyl group, the hydroxyl group, the sulfonyl group, or a combination thereof. Preferably, in one aspect of the invention, the black colorant is prepared by the method disclosed in Japanese Patent Publication No. 2007-84597, which is a carbon black having a carboxyl group and a hydroxyl group on the surface. In detail, in one embodiment of the present invention, one skilled in the art can modify the surface of the carbon black without any treatment by the method disclosed in Japanese Patent Publication No. 2007-84597, so that the carboxyl group and the hydroxyl group can be directly The bond is bonded to the surface of the carbon black to achieve uniform dispersion of the black colorant in the black inkjet ink composition without causing defects such as precipitation and discoloration with other constituent components. Furthermore, as long as it can be uniformly dispersed in the black inkjet ink composition, those skilled in the art can adjust the concentration of the black colorant as needed within the above concentration range. For example, in one aspect of the invention, the concentration of the black colorant may range from 3 weight percent to 8 weight percent. In another aspect of the invention, the black colorant may have a concentration of from 5 weight percent to 10 weight percent. Preferably, in another aspect of the invention, the black colorant may have a concentration of 5 to 8 weight percent. More preferably, in one embodiment of the invention, the concentration of the black colorant may range from 5 weight percent to 7 weight percent.

Accordingly, since the black ink jet ink composition of the present invention includes an appropriate amount of a metal salt and a black colorant compatible with the metal salt, the present invention can achieve excellent printing strength without using a large amount of black colorant.

It should be understood that the above-mentioned "carbon black which has not been treated" means that the surface thereof does not have any functional group such as a phenyl group or the like. Furthermore, the above "carboxyl group and hydroxyl group may be directly bonded to the surface of the carbon black" means There is no other group between the carbon black and the carboxyl group or between the carbon black and the hydroxyl group, so that the carboxyl group and the hydroxyl group can be directly bonded to the surface of the carbon black without any treatment without passing through other groups such as a phenyl group. .

Further, in the above black inkjet ink composition of the present invention, as long as the black inkjet ink composition can maintain the high printing strength advantage, if necessary, those skilled in the art can add other constituent components as needed. The invention is not particularly limited thereto. For example, in one aspect of the invention, the black inkjet ink composition may further comprise a surfactant, a bactericide, or a combination thereof. Furthermore, the content of the additional added components is not particularly limited in the present invention as long as the characteristics of the black ink jet ink composition can be maintained. For example, in one aspect of the invention, the surfactant may be present in an amount from 0.1 weight percent to 1 weight percent. Preferably, in another aspect of the invention, the surfactant may be included in an amount of from 0.5% by weight to 1% by weight. More preferably, in one embodiment of the present invention, the content of the surfactant may be 0.5 weight percent and 0.8 weight percent, but the invention is not limited thereto. Further, in one aspect of the invention, the bactericide may be included in an amount of from 0.01% by weight to 0.5% by weight. Preferably, in another aspect of the invention, the bactericide may be included in an amount of from 0.1% by weight to 0.5% by weight. More preferably, in one embodiment of the present invention, the bactericide may be included in an amount of 0.1% by weight to 0.3% by weight, but the invention is not limited thereto. Further, in the present invention, the surfactant may include one or more compounds which can be used as a surfactant as long as the desired effect can be attained. Similarly, the bactericide may also include more than one compound that acts as a bactericide. In other words, the present invention does not The type and content of the compound contained in the surfactant or bactericide are particularly limited.

Preferred examples of the surfactant may include, but are not limited to, Surfynol 465, Surfynol 485, Surfynol 420, Surfynol 440, and Surfynol 104 (sold by Air Products & Chemicals, Inc.).

Preferred examples of the bactericide include, but are not limited to, NUOSEPT (NudeX Inc., sold by a division of Huls Americal), UCARCIDE (sold by Union Carbide), and VANCIDE ; sold by RTVanderbilt Co.), and Prorox (PROXEL GXL; sold by ICI Americas).

In the above black inkjet ink composition of the present invention, any solvent which can be used in the inkjet ink can be optionally used as the solvent of the present invention, such as water, but the invention is not particularly limited thereto. However, it should be understood that in order to prevent precipitation of the prepared black ink jet ink composition due to metal ions or sulfate ions, in general, the solvent selected may be generally subjected to deionization treatment. For example, in one aspect of the invention, the solvent may be deionized water to avoid precipitation of the prepared black inkjet ink composition due to various metal ions or sulfate ions contained in the water. phenomenon.

Accordingly, according to the black inkjet ink composition of the present invention described above, by using at least one humectant having a relatively large molecular weight and an appropriate amount of a metal salt, the present invention can prepare a high printing strength while avoiding waste of color materials. A black inkjet ink composition such as a conventional disadvantage.

<Preparation of black colorant>

Preparation example

In the present preparation, the black coloring material required for the present invention is prepared by the method disclosed in Japanese Patent Publication No. 2007-84597, which is a carbon black having a carboxyl group and a hydroxyl group on the surface, and the carboxyl group and the hydroxyl group direct bond. Attached to the surface of the carbon black.

<Preparation of black inkjet ink composition>

Examples 1 to 48

Please refer to Table 1, taking the black coloring material prepared by the above preparation example, glycerol (GLY), dipropylene glycol (DPG), triethylene glycol momobutyl ether (TEGMBE), Surfynol ®420, Surfynol® 440, PROXEL GXL, and the metal salts of Examples 1 to 12 shown in Table 1 were uniformly mixed in deionized water as a solvent according to the respective composition ratios shown in Table 1 to prepare Example 1 to 48 black inkjet ink composition.

Comparative example

Referring to Table 1, the comparative examples are substantially similar to the examples except that the constituents of the comparative examples do not contain a metal salt. According to this, you can A black inkjet ink composition free of metal salts was prepared.

<Strength Test>

Print test conditions:

Ink: The black inkjet ink compositions of Examples 1 to 48 and Comparative Examples.

Print paper: Plain paper

Test machine: Spectrometer Datacolor 400

The test results are shown in Table 2.

<Visco test>

Ink: The black inkjet ink compositions of Examples 1 to 48 and Comparative Examples.

Viscosity meter: Brookfield DV-II+Pro test conditions: (1) Viscosity test at room temperature; and test results are shown in Table 2.

Referring to Table 2, the black inkjet ink compositions of Examples 1 to 48 were higher in strength than the black inkjet ink composition of Comparative Example 1 containing no metal salt, showing various divalent metals tested. Salt (eg magnesium chloride, calcium chloride, copper chloride, zinc chloride, magnesium nitrate, calcium nitrate, copper nitrate, zinc nitrate, magnesium acetate, calcium acetate, copper acetate, or zinc acetate) and trivalent metal salts (eg : Aluminum chloride, ferric chloride, aluminum nitrate, or ferric nitrate) does help to improve the strength of black inkjet ink compositions. However, it should be understood that the types of metal salts tested in the examples 1 to 48 of the present invention are merely illustrative of the spirit and scope of the present invention, and the present invention should not be limited to the metal salt species listed above.

Furthermore, the black inkjet ink set of Comparative Example 2 and Comparative Example 3 Although the appearance of strength is better than that of Comparative Example 1, the amount of black pigment used is more than that, which is not in line with economic benefits and environmental protection issues. The efficacy of this technology highlights the effectiveness of black inkjet inks by the addition of polyvalent metal salts, and the purpose of reducing the amount of black pigments.

When the metal salt content of the black ink jet ink composition of the present invention falls within the desired range, the black ink jet ink composition of the present invention can achieve the strength of the conventional black ink jet ink by using a lower black colorant amount and a lower composition amount.

Accordingly, from the results of Table 2, it is understood that not only a black ink jet ink composition having a better strength can be produced in accordance with the present invention, but also the black ink jet ink composition produced has superior storage stability.

In summary, it can be seen from the above test results that the black inkjet ink composition of the present invention can achieve a lower strength by using a lower amount of components by adding an appropriate amount of a divalent metal salt or a trivalent metal salt, thereby achieving a low Cost to create a high-strength black inkjet ink composition.

The above-mentioned embodiments are merely examples for convenience of description, and the scope of the claims is intended to be limited to the above embodiments.

Claims (9)

A black inkjet ink composition comprising: (A) 3 to 10% by weight of a black colorant, wherein the black colorant is a carbon black having a carboxyl group and a hydroxyl group on the surface; (B) 0.1% by weight to 20% by weight of a humectant; (C) 0.01% by weight to 0.3% by weight of a metal salt, wherein the metal salt is a divalent metal salt, a trivalent metal salt, or a combination thereof, and the solubility of the metal salt in water The system is 0.1 mole/L or more; and (D) the remaining solvent. The black inkjet ink composition according to claim 1, wherein each of the humectants has a molecular weight of 80 to 300 g/mole. The black inkjet ink composition according to claim 1, wherein the humectant is a C _3-15 polyol, a C _5-15 alcohol ether, or a combination thereof. The black inkjet ink composition according to claim 1, wherein the metal salt is a magnesium salt, a calcium salt, a copper salt, a zinc salt, an aluminum salt, an iron salt, or combination. The black inkjet ink composition according to claim 1, wherein the metal salt is magnesium chloride, magnesium nitrate, magnesium acetate, calcium chloride, calcium nitrate, calcium acetate, copper chloride, copper nitrate, acetic acid. Copper, zinc chloride, zinc nitrate, zinc acetate, aluminum chloride, aluminum nitrate, iron chloride, iron nitrate, or a combination thereof. The black inkjet ink composition of claim 1, further comprising a surfactant, a bactericide, or a combination thereof. The black inkjet ink composition of claim 6, wherein the surfactant is present in an amount of from 0.1% by weight to 1% by weight. The black inkjet ink composition according to claim 6, wherein the bactericide is contained in an amount of from 0.01% by weight to 0.5% by weight. The black inkjet ink composition according to claim 1, wherein the solvent is water.