JP7071049B2 - Ink composition and inkjet recording method using it - Google Patents

Description

The present invention provides an excellent ink composition having good material suitability for an inkjet head and an inkjet recording device, excellent maintainability, good ejection stability, dryness of printed matter, blocking resistance, and low odor. It relates to the inkjet recording method used.

The inkjet recording method is a recording method in which ink droplets are directly ejected from a very fine inkjet head nozzle onto a recording medium such as paper and adhered to obtain characters or images. This recording method is easy to miniaturize, speed up, reduce noise, save power, and colorize, and since it enables non-contact printing on recording media, it is used not only for home use but also for office use. The scope of application is expanding to commercial printing applications.

Examples of the inkjet ink used in the inkjet recording method include a water-based inkjet ink containing water as a main component and an oil-based inkjet ink containing an organic solvent as a main component.

Specifically, as an oil-based and water-based inkjet ink having excellent storage stability and printing stability of an inkjet ink and ink film resistance, an inkjet ink containing a predetermined alkylene glycol alkyl ether as a solvent is described in Patent Document 1 and Patent Documents. It is disclosed in 2.

Japanese Unexamined Patent Publication No. 2014-501605 Japanese Unexamined Patent Publication No. 2012-057043 Japanese Unexamined Patent Publication No. 3-220144

With recent advances in inkjet technology, the nozzles and internal structures of inkjet heads have become more dense and ultra-miniaturized, and the demand for inkjet inks has become even more stringent in order to print higher-definition images. Specifically, there is a strong demand for member suitability of inkjet heads and inkjet recording devices, maintainability, ejection stability, drying property of printed matter, blocking resistance, reduction of odor, and the like.

The inkjet inks containing the alkylene glycol alkyl ethers of Patent Documents 1 and 2 as a solvent have already been disclosed. However, alkylene glycol alkyl ethers are prone to impurities during the manufacturing process. For example, in the production of the alkylene glycol alkyl ether of Patent Document 3, the content of the obtained alkylene glycol alkyl ether is about 90%, and impurities such as multimers, side reactants, and decomposition products are generated during the production. It is disclosed that it is easy to do.

According to the views of the present inventors, it has been found that the impurities of the solvent contained in the ink composition cannot always satisfy the performance required for recent inkjet inks. In particular, when the solvent contains impurities having a high boiling point component, the drying property of the inkjet ink is lowered, and the printed surface is sticky or tacky. In addition, when the solvent contains impurities of low boiling point components, odor is generated from the inkjet ink, and problems such as dissolution and swelling occur in the plastics and adhesives used for printer members such as inkjet heads. May be done. Further, even if the impurities themselves do not have a high boiling point or a low boiling point, the low purity of the original solvent may make it impossible to satisfy the above-mentioned performance required for the recent inkjet recording method. ..

The present invention has been made in view of the above circumstances, and has good member suitability for an inkjet head and an inkjet recording device, excellent maintainability, good ejection stability, dryness of printed matter, and good blocking resistance, and is low. It is to provide an ink composition for inkjet recording which is an odor.

The present inventor has conducted extensive research in order to solve the above problems, and as a result, the content of impurities derived from the alkylene glycol alkyl ether is reduced in the ink composition for inkjet recording using the alkylene glycol alkyl ether as the solvent. It has been found that the above-mentioned problems can be solved with the ink composition obtained, and the present invention has been completed.

(1) An ink composition for inkjet recording.
It contains at least a coloring material, a resin, and a solvent represented by the following general formula (1).
An ink composition in which the content of impurities derived from the solvent is less than 1.0% by mass in the total amount of the solvent.
R _1- (OR ₂ ) _n -OR ₃ (1)
n: 1 or more and 4 or less integers,
R ₁ : May be branched with 1 or more carbon atoms and 8 or less Alkyl group R ₂ : May be branched with 1 or more carbon atoms and 4 or less alkylene group R ₃ : Hydrogen or branched with 1 or more carbon atoms and 4 or less carbon atoms Good alkyl group

(2) The ink composition according to claim 1, wherein the content of impurities derived from the solvent is 0.5% by mass or more and less than 1.0% by mass in the total amount of the solvent.

(3) The above-mentioned (1) or (2), wherein the impurity derived from the solvent is at least one selected from the group consisting of a multimer of the solvent, a side reaction product of the solvent, and a decomposition product of the solvent. Ink composition.

(4) The ink composition according to any one of (1) to (3), wherein the content of the impurities having a boiling point of more than 300 ° C. is less than 1.0% by mass in the total amount of the solvent.

(5) The ink composition according to any one of (1) to (4), wherein the content of the impurities having a boiling point of less than 150 ° C. is less than 1.0% by mass in the total amount of the solvent.

(6) The ink composition according to any one of (1) to (5) further contains water, and the ink composition is further contained.
A water-based inkjet recording ink composition containing at least a part of the resin as a resin emulsion.

(7) An oil-based inkjet recording ink composition, wherein the ink composition according to any one of (1) to (5) does not contain water.

(8) At least, it contains a coloring material, a resin, and a solvent represented by the following general formula (1).
A water-based inkjet recording ink composition containing water and at least a part of the resin as a resin emulsion.
An ink composition in which the content of impurities derived from the solvent is less than 0.3% by mass in the total amount of the aqueous ink jet recording ink composition.
R _1- (OR ₂ ) _n -OR ₃ (1)
n: 1 or more and 4 or less integers,
R ₁ : May be branched with 1 or more carbon atoms and 8 or less Alkyl group R ₂ : May be branched with 1 or more carbon atoms and 4 or less alkylene group R ₃ : Hydrogen or branched with 1 or more carbon atoms and 4 or less carbon atoms Good alkyl group

(9) At least, it contains a coloring material, a resin, and a solvent represented by the following general formula (1).
An oil-based inkjet recording ink composition that does not contain water.
An ink composition in which the content of impurities derived from the solvent is less than 1.0% by mass in the total amount of the solvent.
R _1- (OR ₂ ) _n -OR ₃ (1)
n: 1 or more and 4 or less integers,
R ₁ : May be branched with 1 or more carbon atoms and 8 or less Alkyl group R ₂ : May be branched with 1 or more carbon atoms and 4 or less alkylene group R ₃ : Hydrogen or branched with 1 or more carbon atoms and 4 or less carbon atoms Good alkyl group

(10) An inkjet recording method for ejecting the ink composition according to any one of (1) to (9) onto the surface of a recording medium by an inkjet method.

(11) A method for producing a printed matter, which comprises a step of ejecting the ink composition according to any one of (1) to (9) onto the surface of a recording medium by an inkjet method.

The present invention provides an excellent ink composition having good material suitability for an inkjet head and an inkjet recording device, excellent maintainability, good ejection stability, dryness of printed matter, blocking resistance, and low odor. can do.

Hereinafter, specific embodiments of the present invention will be described in detail, but the present invention is not limited to the following embodiments, and the present invention is carried out with appropriate modifications within the scope of the object of the present invention. can do.

<Ink composition>
The ink composition for inkjet recording of the present invention is an ink composition containing at least a coloring material, a resin, and a solvent represented by the following general formula (1). Hereinafter, the solvent, the coloring material, and other additives represented by the general formula (1) contained in the ink composition for inkjet recording of the present invention will be described. The content of the solvent represented by the following general formula (1), the resin, the surfactant which is another additive, and the method for preparing the ink composition, which are contained in the ink composition for inkjet recording of the present invention. The recording method using the ink composition will be described in each embodiment of the water-based inkjet recording ink composition and the oil-based inkjet recording ink composition, which will be described later.

[Solvent represented by the general formula (1)]
The solvent represented by the general formula (1) according to the present invention is an alkylene glycol alkyl ether represented by the following general formula (1).

R _1- (OR ₂ ) _n -OR ₃ (1)
n: 1 or more and 4 or less integers,
R ₁ : May be branched with 1 or more carbon atoms and 8 or less Alkyl group R ₂ : May be branched with 1 or more carbon atoms and 4 or less alkylene group R ₃ : Hydrogen or branched with 1 or more carbon atoms and 4 or less carbon atoms Good alkyl group

Further, the solvent represented by the general formula (1) according to the present invention has an impurity content derived from the solvent of less than 1.0% by mass based on the total amount of the solvent represented by the general formula (1). Inkjet recording ink composition that simultaneously satisfies the above requirements for recent inkjet recording methods by setting the content of impurities in the solvent represented by the general formula (1) to less than 1.0% by mass in the total amount of the solvent. Can be. In the present specification, the "impurity derived from the solvent represented by the general formula (1)" means an impurity generated during the production of the solvent represented by the general formula (1), and the content of the impurity. The term means the content of impurities in the solvent represented by the general formula (1), not the content of the entire solvent contained in the ink composition.

The solvent represented by the general formula (1) tends to generate impurities such as multimers, side reactants, and decomposition products during production, and purification for removing the impurities requires many steps and time, so that the solvent is expensive. As a cost, the purity of the solvent represented by the general formula (1) is 99.0% by mass or more (the content of impurities is less than 1.0% by mass in the total amount of the solvent represented by the general formula (1)). Purification is not generally performed. The purity of the solvent represented by the general formula (1) on the market is, for example, 98.0% by mass or more (impurity) as a standard value for diethylene glycol ethylmethyl ether (Wako special grade manufactured by Wako Pure Chemical Industries, Ltd.). Content is less than 2.0% by mass), and triethylene glycol dimethyl ether (Wako first grade manufactured by Wako Pure Chemical Industries, Ltd.) has a standard value of 97.0% by mass or more (impurity content is 3.0% by mass). Less than). However, the content of impurities in the solvent represented by the general formula (1), which is generally marketed and used by the present inventor, is actually 1. It has been confirmed by solvent composition analysis by gas chromatography that it is about 0% by mass or more and 3.0% by mass or less, and contains impurities of the solvent represented by the general formula (1) that is generally commercially available and used. The amount is more than 1.0% by mass in the total amount of the solvent represented by the general formula (1).

However, according to the views of the present inventors, the required requirements may not always be satisfied depending on the impurities contained in the solvent represented by the general formula (1). For example, when the solvent contains impurities having a high boiling point component, the dryness of the ink composition for inkjet recording is lowered, and the printed surface is sticky or tacky. Further, when the solvent contains impurities of a low boiling point component, the odor of the ink composition for inkjet recording may become strong, or problems may occur in the members of the inkjet head and the inkjet recording apparatus. Further, even if the impurity itself is a solvent represented by the general formula (1), the purity of the solvent is less than 99.0% by mass (the content of the impurity is 1.0% by mass or more). Since it is different from the ink design, it may not be possible to meet the required performance.

The ink composition of the present invention can simultaneously satisfy the above-mentioned requirements required for recent inkjet recording methods by adjusting the content of impurities of the solvent represented by the general formula (1), which has not been performed conventionally. It is characterized by the fact that it is possible. Even in the conventional ink composition for inkjet recording, an ink composition using a solvent represented by the general formula (1) has been developed. However, paying attention to the content of impurities derived from the solvent, the ink composition is derived from the solvent. The ink composition containing a solvent having an impurity content of less than 1.0% by mass in the total amount of the solvent represented by the general formula (1) is a novel ink composition which has not been conventionally used.

A method for producing a solvent in which the content of impurities derived from the solvent is less than 1.0% by mass in the total amount of the solvent represented by the general formula (1) will be described later, but for example, a conventional method is commercially available. It can be realized by further purifying the solvent represented by the general formula (1). For example, by repeatedly distilling the solvent represented by the general formula (1) on the market, reducing the step size of the distillation temperature so as not to contain impurities as much as possible, or by repeating the extraction. In the industrial manufacturing process, it can be realized by further taking measures to suppress contamination in addition to the above-mentioned process.

Further, the solvent represented by the general formula (1) according to the present invention may contain 0.5% by mass or more of impurities derived from the solvent in the total amount of the solvent represented by the general formula (1). .. By setting the content of impurities of the solvent represented by the general formula (1) to 0.5% by mass or more in the total amount of the solvent, the manufacturing cost of the solvent represented by the general formula (1) by purification such as distillation and extraction is achieved. Can be suppressed from increasing significantly. Therefore, it is possible to produce an ink composition having good physical characteristics that does not cause any problem in actual use within a low cost range.

The content of impurities derived from the solvent of the solvent represented by the general formula (1) is preferably 0.9% by mass or less based on the total amount of the solvent represented by the general formula (1), and the general formula (1). It is more preferably 0.8% by mass or less in the total amount of the solvent represented by the general formula (1), further preferably 0.7% by mass or less in the total amount of the solvent represented by the general formula (1), and the general formula (1). It is still more preferably 0.6% by mass or less in the total amount of the solvent represented by the above, and even more preferably 0.1% by mass or less in the total amount of the solvent represented by the general formula (1). Further, the content of impurities of the solvent represented by the general formula (1) can be measured by gas chromatography based on, for example, JIS K0114.

In the case of the water-based inkjet recording ink composition described later, the content of impurities derived from the solvent of the solvent represented by the general formula (1) is 0.30% by mass or less in the total amount of the inkjet recording ink composition. It is preferably 0.25% by mass or less, more preferably 0.15% by mass or less. Further, in the case of an oil-based inkjet recording ink composition described later, the content of impurities derived from the solvent of the solvent represented by the general formula (1) is 1.0 mass in the total amount of the inkjet recording ink composition. It is preferably less than%, more preferably 0.8% by mass or less, still more preferably 0.5% by mass or less.

Examples of multimers, side reactants, decomposition products and the like contained as impurities derived from the solvent include, for example, the value n of the solvent represented by the general formula (1), R ₁ , R ₂ and R ₃ . An ink that is different from the intended one, has a higher boiling point than the solvent component represented by the general formula (1) intentionally contained in the ink composition (for example, one having a boiling point of more than 300 ° C.), and an ink. Those having a lower boiling point than the component of the solvent represented by the general formula (1) intentionally contained in the composition (for example, those having a boiling point of less than 150 ° C.), alcohols and esters, aldehydes, ketones , Acids, etc., but are not limited to these.

Specific examples of the multimer, side reaction product, and decomposition product contained as impurities derived from the solvent are triethylene when the solvent represented by the general formula (1) is, for example, diethylene glycol diethyl ether. Glycol (boiling point 285 ° C), tetraethylene glycol (boiling point 327 ° C), polyethylene glycol (boiling point 330 ° C. or higher), ethylene glycol monoethyl ether (boiling point 135 ° C.), ethylene glycol diethyl ether (boiling point 121 ° C.), ethoxyethanol (boiling point) 135 ° C.), ethanol (boiling point: 78 ° C.), acetaldehyde (boiling point 20 ° C.), diethyl ether (boiling point 35 ° C.), diethyl ketone (boiling point 101 ° C.), ethyl acetate (boiling point 77 ° C.), etc. It is not limited to these.

When the solvent represented by the general formula (1) is triethylene glycol monobutyl ether, tetraethylene glycol monobutyl ether (boiling point: 304 ° C.), triethylene glycol (boiling point 285 ° C.), tetraethylene glycol (boiling point 327 ° C.) ), Polyethylene glycol (boiling point 330 ° C or higher), ethylene glycol monoethyl ether (boiling point: 135 ° C), ethoxyethanol (boiling point 135 ° C), dibutyl ether (boiling point 142 ° C), butyl ethyl ether (boiling point 92 ° C), ethanol ( (Boiling point 78 ° C.), 1-butanol (boiling point 117 ° C.), and the like, but are not limited thereto.

When the solvent represented by the general formula (1) is tripropylene glycol monomethyl ether, polypropylene glycol (boiling point of 300 ° C. or higher), tetrapropylene glycol monomethyl ether (boiling point: 330 ° C.), propylene glycol dimethyl ether (boiling point of 97 ° C.) ), Propylene glycol monomethyl ether (boiling point: 120 ° C.), methanol (boiling point: 65 ° C.), 1-propanol (boiling point: 98 ° C.), 2-propanol (boiling point: 82 ° C.), methoxypropanol (boiling point: 119 ° C.), diisopropyl ether. (Boiling point 69 ° C.) and the like can be mentioned, but the present invention is not limited thereto.

When the solvent represented by the general formula (1) is diethylene glycol methyl ethyl ether, triethylene glycol (boiling point of 285 ° C.), tetraethylene glycol (boiling point of 327 ° C.), polyethylene glycol (boiling point of 330 ° C. or higher), ethylene glycol Monoethyl ether (boiling point 135 ° C), ethylene glycol monomethyl ether (boiling point 124 ° C), ethylene glycol diethyl ether (boiling point 121 ° C), ethylene glycol dimethyl ether (boiling point 98 ° C), diethyl ether (boiling point 35 ° C), ethyl methyl ether (boiling point 35 ° C) Diethyl ketone (boiling point 101 ° C.), dimethyl ketone (boiling point 57 ° C.), ethylmethyl ketone (boiling point 80 ° C.), ethoxyethanol (boiling point 135 ° C.), ethanol (boiling point 78 ° C.), etc. Yes, but not limited to these.

When the solvent represented by the general formula (1) is tetraethylene glycol dimethyl ether, triethylene glycol (boiling point of 285 ° C.), tetraethylene glycol (boiling point of 327 ° C.), polyethylene glycol (boiling point of 330 ° C. or higher), polyethylene glycol. Dimethyl ether (boiling point 300 ° C or higher), ethylene glycol monomethyl ether (boiling point 124 ° C.), ethylene glycol diethyl ether (boiling point 121 ° C.), ethylene glycol dimethyl ether (boiling point 98 ° C.), diethyl ether (boiling point 35 ° C. or higher), ethoxyethanol (boiling point) 135 ° C.), ethanol (boiling point 78 ° C.), methanol (boiling point 65 ° C.) and the like, but are not limited thereto.

The impurities derived from the solvent represented by the general formula (1) are not particularly limited as long as they are derived from the solvent represented by the general formula (1) and are less than 1.0% by mass in the total amount of the solvent. The impurities other than the solvent represented by the general formula (1) are preferably less than 0.9% by mass, more preferably less than 0.8% by mass, and less than 0.7% by mass in the total amount of the solvent. More preferably, it is more preferably less than 0.6% by mass. Further, it is more preferable that impurities other than the solvent represented by the general formula (1) and / or impurities below 150 ° C or above 300 ° C are less than 0.9% by mass, and less than 0.8% by mass in the total amount of the solvent. It is more preferably less than 0.7% by mass, still more preferably less than 0.6% by mass. If the impurities derived from the solvent represented by the general formula (1) are less than 1.0% by mass in the total amount of the solvent other than the impurities represented by the general formula (1), the influence of the impurities on the ink composition. Can be reduced.

When the impurity derived from the solvent represented by the general formula (1) is a solvent other than the solvent represented by the general formula (1) and / or a solvent having a boiling point of more than 300 ° C or less than 150 ° C, it is general. The content of impurities derived from the solvent represented by the formula (1) is preferably less than 1.0% by mass, and less than 0.9% by mass, based on the total amount of the solvent represented by the general formula (1). It is more preferably less than 0.8% by mass, still more preferably less than 0.7% by mass, and even more preferably less than 0.6% by mass.

Further, the content of impurities derived from the solvent represented by the general formula (1) having a boiling point of more than 300 ° C. is preferably less than 1.0% by mass based on the total amount of the solvent represented by the general formula (1). , 0.8% by mass, more preferably less than 0.6% by mass, still more preferably less than 0.5% by mass, and even less than 0.3% by mass. Even more preferable. Further, the impurities of the solvent represented by the general formula (1) do not substantially contain impurities having a boiling point of more than 300 ° C. (less than 0.1% by mass in the total amount of the solvent represented by the general formula (1)). Is even more preferable. Inkjet recording because the content of impurities derived from the solvent represented by the general formula (1) having a boiling point of more than 300 ° C. is less than 1.0% by mass in the total amount of the solvent represented by the general formula (1). The drying property of the ink composition for use is improved, and the blocking resistance of the printed matter is improved.

Further, the content of impurities derived from the solvent represented by the general formula (1) having a boiling point of less than 150 ° C. is preferably less than 1.0% by mass based on the total amount of the solvent represented by the general formula (1). , 0.8% by mass, more preferably less than 0.6% by mass, still more preferably less than 0.5% by mass, and even less than 0.3% by mass. Even more preferable. Further, the impurities of the solvent represented by the general formula (1) do not substantially contain impurities having a boiling point of less than 150 ° C. (less than 0.1% by mass in the total amount of the solvent represented by the general formula (1)). Is even more preferable. The content of impurities derived from the solvent represented by the general formula (1) having a boiling point of less than 150 ° C. is less than 1.0% by mass based on the total amount of the solvent represented by the general formula (1). It is possible to suppress the odor of the ink composition for inkjet recording due to the high volatility, and it is possible to reduce the swelling or dissolution of the resin member of the inkjet head or the inkjet recording device due to the impurities of the low boiling point component.

The boiling point of the solvent represented by the general formula (1) is preferably 150 ° C. or higher and 300 ° C. or lower, the lower limit value is more preferably 180 ° C. or higher, and the upper limit value is 280 ° C. or lower. Is more preferable. When the boiling point of the solvent represented by the general formula (1) is 150 ° C. or higher, the odor of the ink composition for inkjet recording can be reduced. Further, it is possible to prevent the solvent in the ink composition from volatilizing and increase the viscosity of the ink composition, and to improve the ejection stability of the ink composition for inkjet recording. When the boiling point of the solvent represented by the general formula (1) is 300 ° C. or lower, the dryness of the ink composition for inkjet recording is improved, the occurrence of stickiness and tack on the printed surface is suppressed, and the blocking resistance of the printed matter is suppressed. Can be improved.

The inkjet recording ink composition of the present invention is not limited to the oil-based inkjet recording ink composition containing an organic solvent as a main component. For example, an aqueous ink jet recording ink composition containing water as a main component and also containing a solvent represented by the general formula (1) is also included in the scope of the present invention.

The solvent represented by the general formula (1) that can be contained in the ink composition for inkjet recording of the present invention is, for example, ethylene glycol mono-n-butyl ether, ethylene glycol mono-isobutyl ether, ethylene glycol mono-t-. Butyl ether, ethylene glycol mono-2-ethylhexyl ether, diethylene glycol monomethyl (or ethyl, propyl, isopropyl, n-butyl, isobutyl, t-butyl, 2-ethylhexyl) ether, triethylene glycol monomethyl (or ethyl, propyl, isopropyl, n) -Butyl, isobutyl, t-butyl, 2-ethylhexyl) ether, tetraethylene glycol monomethyl ether, propylene glycol mono-n-butyl ether, propylene glycol mono-isobutyl ether, propylene glycol mono-t-butyl ether, propylene glycol mono-2- Ethylhexyl ether, dipropylene glycol monomethyl (or ethyl, propyl, isopropyl, n-butyl, isobutyl, t-butyl, 2-ethylhexyl) ether, tripropylene glycol monomethyl (or ethyl, propyl, isopropyl, n-butyl, isobutyl, t -Alkylene glycol monoalkyl ethers such as butyl) ether, tetrapropylene glycol monomethyl ether; ethylene glycol dibutyl ether, ethylene glycol dipropyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol ethylmethyl ether, diethylene glycol dipropyl ether, diethylene glycol propyl Methyl ether, diethylene glycol dibutyl ether, diethylene glycol butyl methyl ether, diethylene glycol butyl ethyl ether, diethylene glycol methyl-2-ethylhexyl ether, triethylene glycol dimethyl ether, triethylene glycol diethyl ether, triethylene glycol ethyl methyl ether, tetraethylene glycol dimethyl ether, tetraethylene Glycol diethyl ether, tetraethylene glycol ethyl methyl ether, propylene glycol diethyl ether, propylene glycol ethyl methyl ether, propylene glycol methyl propyl ether, propylene glycol methyl buty Luether, propylene glycol methyl-2-ethylhexyl ether, dipropylene glycol dimethyl ether, dipropylene glycol diethyl ether, dipropylene glycol ethyl methyl ether, dipropylene glycol methyl propyl ether, dipropylene glycol dipropyl ether, tripropylene glycol dimethyl ether, tripropylene Examples thereof include dialkyl ethers of polyhydric alcohols such as glycol diethyl ether and tripropylene glycol ethyl methyl ether. Further, it may be a mixed solvent in which two or more kinds of these are mixed. The solvent can be used in both the water-based inkjet recording ink composition and the oil-based inkjet recording ink composition.

Diethylene glycol monomethyl (or ethyl, propyl, isopropyl, n-butyl, isobutyl, t-butyl, 2-butyl, 2-butyl, from the viewpoint of the effect of suppressing nozzle drying and stabilizing ejection, low odor, and stability of the emulsion in water-based inks. Ethylhexyl) ether, triethylene glycol monomethyl (or ethyl, propyl, isopropyl, n-butyl, isobutyl, t-butyl, 2-ethylhexyl) ether, tetraethylene glycol monomethylAel, propylene glycol mono-n-butyl ether, propylene glycol mono- Isobutyl ether, propylene glycol mono-t-butyl ether, propylene glycol mono-2-ethylhexyl ether, dipropylene glycol monomethyl (or ethyl, propyl, isopropyl, n-butyl, isobutyl, t-butyl, 2-ethylhexyl) ether, tripropylene Glycolmonomethyl (or ethyl, propyl, isopropyl, n-butyl, isobutyl, t-butyl) ethers and the like are preferred. These solvents are particularly preferable as solvents for water-based inkjet recording ink compositions.

Diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol ethyl methyl from the viewpoints of compatibility with the resin in the ink composition, permeability to the substrate on which the ink is ejected, leveling property on the substrate surface, and dryness. Ether, Diethylene glycol dipropyl ether, Diethylene glycol propylmethyl ether, Diethylene glycol dibutyl ether, Diethylene glycol butylmethyl ether, Diethylene glycol butyl ethyl ether, Diethylene glycol methyl-2-ethylhexyl ether, Triethylene glycol dimethyl ether, Triethylene glycol diethyl ether, Triethylene glycol ethyl methyl Ether, tetraethylene glycol dimethyl ether, propylene glycol diethyl ether, propylene glycol ethyl methyl ether, propylene glycol methyl propyl ether, propylene glycol methyl butyl ether, propylene glycol methyl-2-ethylhexyl ether, dipropylene glycol dimethyl ether, dipropylene glycol diethyl ether, di Preferable examples include propylene glycol ethyl methyl ether, dipropylene glycol methyl propyl ether, dipropylene glycol dipropyl ether, tripropylene glycol dimethyl ether, and tripropylene glycol ethyl methyl ether. These solvents are particularly preferable as solvents for oil-based inkjet recording ink compositions.

[Color material]
The coloring material contained in the ink composition for inkjet recording of the present invention is not particularly limited and may be dye-based or pigment-based, but the printed matter has water resistance and light resistance. It is preferable to use a pigment-based ink having good resistance such as. The pigments that can be used in the inkjet recording ink composition of the present invention are not particularly limited, and examples thereof include organic pigments and inorganic pigments used in conventional inkjet recording ink compositions. These may be used alone or in combination of two or more.

Specific organic pigments include, for example, insoluble azo pigments, soluble azo pigments, derivatives from dyes, phthalocyanine-based organic pigments, quinacridone-based organic pigments, perylene-based organic pigments, dioxazine-based organic pigments, nickel-azo pigments, and isoindolinone. Organics such as organic pigments, pyranthron organic pigments, thioindigo organic pigments, condensed azo organic pigments, benzimidazolone organic pigments, quinophthalone organic pigments, isoindolin organic pigments, quinacridone solid solution pigments, perylene solid solution pigments, etc. Examples of the solid solution pigment and other pigments include carbon black and the like.

To exemplify organic pigments by color index (CI) number, C.I. I. Pigment Yellow 1, 2, 3, 12, 13, 14, 16, 17, 20, 24, 73, 74, 75, 83, 93, 95, 97, 98, 109, 110, 114, 117, 120, 125, 128, 129, 130, 137, 138, 139, 147, 148, 150, 151, 153, 154, 155, 166, 168, 180, 185, 213, 214, C.I. I. Pigment Red 5, 7, 9, 12, 48, 49, 52, 53, 57, 97, 112, 122, 123, 149, 168, 177, 180, 184, 192, 202, 206, 209, 215, 216, 217, 220, 223, 224, 226, 227, 228, 238, 240, 254, C.I. I. Pigment Orange 16, 36, 43, 51, 55, 59, 61, 64, 71, C.I. I. Pigment Violet 19, 23, 29, 30, 37, 40, 50, C.I. I. Pigment Blue 15, 15: 1, 15: 3, 15: 4, 15: 6, 16, 22, 60, 64, C.I. I. Pigment Green 7, 36, 58, C.I. I. Pigment Brown 23, 25, 26, C.I. I. Pigment Black 7 and the like.

Specific examples of the inorganic pigments that can be used in the ink composition for inkjet recording of the present invention include titanium oxide, barium sulfate, calcium carbonate, zinc oxide, barium carbonate, silica, talc, clay, synthetic mica, alumina, and zinc. Hana, lead sulfate, yellow lead, zinc oxide, red iron oxide (III), cadmium red, ultramarine blue, dark blue, chromium oxide green, cobalt green, amber, titanium black, synthetic iron black, inorganic solid solution pigments, etc. be able to. These coloring materials (organic pigments, inorganic pigments, other pigments, etc.) can be used in both the water-based inkjet recording ink composition and the oil-based inkjet recording ink composition. When a dye system is used in the oil-based inkjet recording ink composition described later, it is preferable to use an oil-based dye.

In the ink composition for inkjet recording of the present invention, the average dispersed particle size of the pigment that can be contained is not particularly limited as long as it can develop a desired color. Although it depends on the type of pigment used, the number average particle size is preferably in the range of 5 nm or more and 300 nm or less, preferably 20 nm or more, from the viewpoint of good dispersibility and dispersion stability of the pigment and sufficient coloring power. It is more preferably 200 nm or less, and further preferably 30 nm or more and 150 nm or less. When the number average particle size is equal to or less than the above upper limit, the solvent in the ink composition is prevented from volatilizing to increase the viscosity of the ink composition, and the ejection stability of the ink composition for inkjet recording is improved. be able to. If the number average particle size is not more than the above lower limit, the light resistance may decrease. In this embodiment, the number average particle size of the pigment is measured at a measurement temperature of 25 ° C. using a concentrated particle size analyzer (manufactured by Otsuka Electronics Co., Ltd., model: FPAR-1000).

The content of the pigment that can be used in the ink composition for inkjet recording of the present invention is not particularly limited as long as a desired image can be formed, and is appropriately adjusted. Specifically, although it varies depending on the type of pigment, it is preferably in the range of 0.05% by mass or more and 20% by mass or less, and in the range of 0.1% by mass or more and 10% by mass or less in the total amount of the ink composition. Is more preferable. When the content of the pigment is in the range of 0.05% by mass or more and 20% by mass or less, the balance between the dispersion stability of the pigment and the coloring power can be excellent.

[Other additives]
If necessary, the ink composition of the present invention may further contain a conventionally known additive. Additives include, for example, viscosity regulators, surfactants, pH regulators, surface tension regulators, leveling agents, defoamers, antioxidants, preservatives, fungicides, charge regulators, wetting agents and the like. Known additives may be mentioned as optional ingredients. These additives can be used in both the water-based inkjet recording ink composition and the oil-based inkjet recording ink composition.

Hereinafter, the water-based inkjet recording ink composition and the oil-based inkjet recording ink composition will be described.

<Ink composition for water-based inkjet recording>
[solvent]
The ink composition of the present embodiment contains water as a main component and also contains a solvent represented by the general formula (1) (hereinafter, simply referred to as an ink composition for water-based inkjet recording). It may be written).

In the water-based inkjet recording ink composition of the present embodiment, it is preferable to use deionized water as the water contained, not the one containing various ions. The content of water is not particularly limited as long as it can disperse or dissolve each component, but it may be in the range of 10% by mass or more and 95% by mass or less in the total amount of the ink composition. It is preferable that the content is preferably in the range of 20% by mass or more and 95% by mass or less in the total amount of the ink composition, and particularly preferably in the range of 30% by mass or more and 90% by mass or less in the total amount of the ink composition.

Further, in the water-based inkjet recording ink composition of the present embodiment, the content of the entire ink composition of the solvent represented by the general formula (1) is 1% by mass or more and 50% by mass or less in the total amount of the ink composition. It is preferably in the range of 1% by mass or more and 40% by mass or less in the total amount of the ink composition, and particularly preferably in the range of 3% by mass or more and 30% by mass or less in the total amount of the ink composition. It is preferably inside.

[Other solvents]
The water-based inkjet recording ink composition of the present embodiment may contain other solvents as long as the design performance is not impaired. The boiling point of the other solvent is preferably 150 ° C. or higher and 300 ° C. or lower. The volatility of the solvent is high because the boiling point of the other solvent contained in the aqueous inkjet recording ink composition of the present embodiment (hereinafter, may be simply referred to as another solvent) is 150 ° C. or higher. It is possible to suppress the odor of the ink composition for inkjet recording due to this, and there is a risk that problems will occur due to swelling or dissolution of the resin member of the inkjet head or inkjet recording device due to other solvents having a low boiling point component. Can be reduced. When the boiling point of the other solvent is 300 ° C. or lower, the drying property of the ink composition for inkjet recording is improved, and the blocking resistance of the printed matter is improved.

Examples of other solvents having a boiling point of 280 ° C. or higher and 300 ° C. or lower include triethylene glycol (boiling point: 285 ° C.), glycerin (boiling point: 290 ° C.), trimethylolethane, trimethylolpropane and the like. Other solvents with a boiling point of 250 ° C or higher and lower than 280 ° C include tripropylene glycol (boiling point: 268 ° C), 1,6-hexanediol (boiling point: 250 ° C), and 3-methyl-1,5-pentanediol (boiling point). : 250 ° C.), etc. Other solvents with a boiling point of 200 ° C or higher and lower than 250 ° C include dipropylene glycol (boiling point: 232 ° C), diethylene glycol (boiling point: 244 ° C), dipropylene glycol monomethyl ether acetate (boiling point: 209 ° C), and diethylene glycol monobutyl ether acetate. (Boiling point: 247 ° C), 1,3-propanediol (boiling point: 214 ° C), 1,3-butanediol (boiling point: 208 ° C), 1,4-butanediol (boiling point: 230 ° C), 1,2- Pentandiol (boiling point: 210 ° C), 1,2-hexanediol (boiling point: 223 ° C), 1,5-pentanediol (boiling point: 242 ° C), 1,6-hexanediol (boiling point: 250 ° C), 2, 2,4-trimethyl-1,3-pentanediol (boiling point: 232 ° C.), 3-methyl-1,3-butanediol (boiling point: 203 ° C.), 2-methyl-1,3-pentanediol (boiling point: 214 ° C.) ° C.), 2-ethyl-1,3-hexanediol (boiling point: 244 ° C.), and the like. Other solvents with a boiling point of 180 ° C or higher and lower than 200 ° C include ethylene glycol (boiling point: 197 ° C), propylene glycol (boiling point: 187 ° C), 1,2-butanediol (boiling point: 193 ° C), and 2-methyl-. 2,4-pentanediol (boiling point: 198 ° C.) and the like can be mentioned.

[Pigment dispersant]
The water-based inkjet recording ink composition of the present embodiment may contain a pigment dispersant. Here, the pigment dispersant means a resin or a surfactant having a function of improving the dispersibility of the pigment in the ink by adhering to a part of the surface of the pigment.

The pigment dispersant that can be used in the water-based inkjet recording ink composition of the present embodiment is not particularly limited. For example, cationic, anionic, nonionic, amphoteric, silicone (silicon) -based, and fluorine-based surfactants can be used. Among the surfactants, the polymer surfactants (polymer dispersants) as exemplified below are preferable.

As the pigment dispersant that can be used in the water-based inkjet recording ink composition of the present embodiment, a water-soluble polymer dispersant can be preferably used. The water-soluble polymer dispersant has, for example, a polyester-based, polyacrylic-based, polyurethane-based, polyamine-based, or polycaptolactone-based main chain, and has an amino group, a carboxy group, a sulfo group, and a hydroxy group in the side chain. Examples thereof include a dispersant having a polar group such as. For example, (co) polymers of unsaturated carboxylic acid esters such as polyacrylic acid esters; copolymers of aromatic vinyl compounds such as styrene and α-methylstyrene and unsaturated carboxylic acid esters such as acrylic acid esters; (Partial) amine salts, (partial) ammonium salts and (partial) alkylamine salts of (co) polymers of unsaturated carboxylic acids such as polyacrylic acid; hydroxyl group-containing unsaturated carboxylic acid esters such as hydroxyl group-containing polyacrylic acid esters. (Co) polymers and their modifications; polyurethanes; unsaturated polyamides; polysiloxanes; long-chain polyaminoamide phosphates; polyethyleneimine derivatives (poly (lower alkyleneimine) and free carboxyl group-containing polyesters Amids obtained by the reaction and their bases); Polyallylamine derivatives (polyallylamine and polyesters having a free carboxyl group, polyamides, or cocondensates of esters and amides (polyesteramides)) are selected from three compounds. Reaction products obtained by reacting with one or more kinds of compounds) and the like can be mentioned. Of these, a water-soluble polymer dispersant containing a (meth) acrylic resin is preferable from the viewpoint of ink dispersion stability and image sharpness of printed matter.

Specific examples of the water-soluble polymer dispersant include SMA1440, SMA2625, SMA17352, SMA3840, SMA1000, SMA2000, SMA3000, BASF Japan, JONCRYL67, JONCRYL678, JONCRYL586, JONCRYL611, JONCRYL618, JONCRYL618, JONCRYL618. －ＪＤＸ５０５０、ＥＦＫＡ４５５０、ＥＦＫＡ４５６０、ＥＦＫＡ４５８５、ＥＦＫＡ５２２０、ＥＦＫＡ６２３０、ルーブリゾール社製ＳＯＬＳＰＥＲＳＥ２００００、ＳＯＬＳＰＥＲＳＥ２７０００、ＳＯＬＳＰＥＲＳＥ４１０００、ＳＯＬＳＰＥＲＳＥ４１０９０、ＳＯＬＳＰＥＲＳＥ４３０００、ＳＯＬＳＰＥＲＳＥ４４０００、ＳＯＬＳＰＥＲＳＥ４６０００、ＳＯＬＳＰＥＲＳＥ４７０００、ＳＯＬＳＰＥＲＳＥ５４０００、ビックケミー社製ＢＹＫＪＥＴ－９１５０、ＢＹＫＪＥＴ－９１５１、ＢＹＫＪＥＴ－９１７０、 Examples thereof include DISPERBYK-168, DISPERBYK-190, DISPERBYK-198, DISPERBYK-2010, DISPERBYK-2012, DISPERBYK-2015, and the like. These pigment dispersants can be suitably used in water-based inkjet recording ink compositions.

In the water-based inkjet recording ink composition of the present embodiment, the pigment that can be used is a pigment dispersion in which the pigment is dispersed in a water-soluble solvent with a pigment dispersant, but the pigment is directly hydrophilic on the surface of the pigment. It may be a pigment dispersion which is a self-dispersion type pigment modified with a sex group. In the present embodiment, as the pigment that can be used for the ink for inkjet recording, a plurality of the above-mentioned organic pigments and inorganic pigments may be used in combination, and a pigment dispersion dispersed in a water-soluble solvent by the above-mentioned pigment dispersant. And the self-dispersion pigment described later may be used in combination.

[Self-dispersed pigment]
Examples of the self-dispersive pigment that can be used in the aqueous inkjet recording ink composition of the present embodiment include a carbonyl group, a carboxyl group, and a hydroxyl group described in JP-A-2012-51357 as a hydrophilic group. , A sulfonic acid group, a phosphorus-containing group, and the like. As commercially available products, for example, "CAB-O-JET 200, CAB-O-JET 250C, CAB-O-JET 260M, CAB-O-JET 270Y, CAB-O-JET 740Y, CAB-" manufactured by Cabot. O-JET 300, CAB-O-JET 400, CAB-O-JET 450C, CAB-O-JET 465M, CAB-O-JET 470Y, CAB-O-JET 480V, CAB-O-JET 352K, CAB-O -JET 554B, CAB-O-JET 1027R "," Microjet black Black 162, Aqua-Black 001, BONJET BLACK CW-1, BONJET BLACK CW-2, BONJET BLACK CW-3 "manufactured by Orient Chemical Industry Co., Ltd., Tokai "Aqua-Black 162, Aqua-Black 001" manufactured by Carbon Co., Ltd., LIOJET WD BLACK 002C manufactured by Toyo Ink Mfg. Co., Ltd., "SF Color" manufactured by Sanyo Dye Co., Ltd., "Fuji SP" manufactured by Fuji Dye Co., Ltd. Examples include "Color" and "Hostajet" manufactured by Clariant.

[resin]
The water-based inkjet recording ink composition of the present embodiment contains a resin. By containing the resin in the ink composition, the water resistance of the printed matter printed by the ink is improved. Further, in the water-based inkjet recording ink composition of the present embodiment, it is preferable that at least a part of the resin contained is contained as a resin emulsion. In the aqueous inkjet recording ink composition of the present embodiment, the resin emulsion means an aqueous dispersion in which the continuous phase is a water-soluble solvent and the dispersed particles are resin fine particles. By forming the resin emulsion, the resin can be dispersed as resin fine particles in the water-based inkjet recording ink composition by the electrostatic repulsive force. The resin emulsion generally has the property of thickening and aggregating when the water-soluble solvent, which is a continuous phase, decreases due to evaporation, permeation, etc., and has the effect of promoting the fixation of the coloring material on the recording medium.

The resin contained in the water-based inkjet recording ink composition of the present embodiment is not particularly limited as long as it can exhibit desired water resistance, and is, for example, an acrylic resin, a polystyrene resin, or a polyester resin. , Vinyl chloride resin, vinyl acetate resin, vinyl chloride vinyl acetate copolymer resin, polyethylene resin, urethane resin, silicone (silicon) resin, acrylamide resin, epoxy resin, or copolymer resins or mixtures thereof can be used. These are preferable in that they can improve solvent resistance in addition to water resistance. Above all, it is preferable that it contains an acrylic resin because it can be excellent in discharge stability, water resistance and solvent resistance.

The acrylic resin is not particularly limited as long as it is contained as the main component of the monomer constituting the (meth) acrylic acid ester monomer. As the (meth) acrylic acid ester monomer, a known compound can be used, and a monofunctional (meth) acrylic acid ester can be preferably used. For example, (meth) acrylic acid alkyl ester, (meth) acrylic acid aralkyl ester, (meth) acrylic acid alkoxyalkyl ester and the like can be mentioned. Specifically, for example, methyl (meth) acrylate, ethyl (meth) acrylate, -n-propyl (meth) acrylate, -iso-propyl (meth) acrylate, -n-butyl (meth) acrylate. , (Meta) Acrylic Acid-sec-Butyl, (Meta) Acrylic Acid-iso-Butyl, (Meta) Acrylic Acid-tert-Butyl, (Meta) Acrylic Acid Pentyl, (Meta) Acrylic Acid Neopentyl, (Meta) Acrylic Acid Hexil, (meth) acrylic acid-2-ethylhexyl, (meth) acrylate-octyl, (meth) acrylic acid-iso-octyl, (meth) acrylic acid nonyl, (meth) acrylic acid-iso-nonyl, (meth) acrylic Dodecyl acid, tridecyl (meth) acrylate, stearyl (meth) acrylate, cyclopentyl (meth) acrylate, cyclohexyl (meth) acrylate, -2-methylcyclohexyl (meth) acrylate, dicyclopenta (meth) acrylate Nyl, dicyclopentenyl (meth) acrylate, dicyclopentanyloxyethyl (meth) acrylate, dicyclopentenyloxyethyl (meth) acrylate, dicyclohexyl (meth) acrylate, isobornyl (meth) acrylate, (meth) ) Adamantyl acrylate, allyl (meth) acrylate, propagil (meth) acrylate, phenyl (meth) acrylate, naphthyl (meth) acrylate, anthrasenyl (meth) acrylate, anthraninonyl (meth) acrylate, ( Piperonyl acrylate, (meth) salicyl acrylate, (meth) acrylate frill, (meth) acrylate flufuryl, (meth) acrylate tetrahydrofuryl, (meth) acrylate tetrahydrofurfuryl, (meth) acrylate pyranyl , (Meta) benzyl acrylate, (meth) phenethyl acrylate, (meth) cresyl acrylate, (meth) glycidyl acrylate, (meth) acrylate-3,4-epoxycyclohexylmethyl, (meth) acrylate-3 , 4-Epoxycyclohexylethyl, (meth) acrylic acid-1,1,1-trifluoroethyl, (meth) acrylic acid perfluorethyl, (meth) acrylic acid perfluoro-n-propyl, (meth) acrylic acid Perfluoro-iso-propyl, heptadecafluorodecyl (meth) acrylate, triphenylmethyl (meth) acrylate, cumil (meth) acrylate, -3- (N, N-dimethylamino) (meth) acrylate Propyl, methoxyethyl (meth) acrylate, ethoxyethyl (meth) acrylate, butoxyethyl (meth) acrylate, -2-cyanoethyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, (meth) acrylate (Meta) acrylic acid esters such as diethylaminoethyl, trimethoxysilylpropyl (meth) acrylate, triethoxysilylpropyl (meth) acrylate, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropylmethyldimethoxysilane , Etc. can be mentioned. In addition, "(meth) acrylic" means both "acrylic" and "methacrylic". These monomers can be obtained from Mitsubishi Rayon Co., Ltd., NOF Corporation, Mitsubishi Chemical Co., Ltd., Hitachi Kasei Kogyo Co., Ltd., and the like.

The monomer constituting the acrylic resin may include an acid group-containing monomer having an acid group, a hydroxyl group-containing monomer having a hydroxyl group, and an amino group-containing monomer having an amino group. Examples of the acid group-containing monomer having an acid group include acrylic acid, methacrylic acid, itaconic acid, fumaric acid, maleic acid, crotonic acid, citraconic acid, maleic anhydride, maleic acid monomethyl ester, and maleic acid monobutyl ester. Carboxyl-containing aliphatic monomers such as itaconic acid monomethyl ester, itaconic acid monobutyl ester, vinyl benzoic acid, monohydroxyethyl oxalate (meth) acrylate, and carboxyl group-terminated caprolactone-modified (meth) acrylate Examples thereof include a carboxyl group-containing monomer having a saturated double bond and a carboxyl group. The hydroxyl group-containing monomer containing a hydroxyl group is not particularly limited as long as it has an unsaturated double bond and a hydroxyl group, and is, for example, 2-hydroxyethyl (meth) acrylate or 2-hydroxypropyl (meth). ) Acrylate, 3-hydroxyethyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, caprolactone-modified hydroxy (meth) acrylate, methyl α- (Hydroxymethyl) (meth) acrylate, ethyl α- (hydroxymethyl) (meth) acrylate, n-butyl α- (hydroxymethyl) (meth) acrylate, 1,4-cyclohexanedimethanol mono (meth) acrylate, 4- Hydroxybutyl (meth) acrylate and the like can be mentioned. The amino group-containing monomer is not particularly limited as long as it has an unsaturated double bond and an amino group, and is, for example, (meth) acrylamide N-monomethyl (meth) acrylamide and N-monoethyl (meth). ) Acrylamide, N, N-dimethyl (meth) acrylamide, Nn-propyl (meth) acrylamide, N-isopropyl (meth) acrylamide, methylenebis (meth) acrylamide, N-methylol (meth) acrylamide, N-butoxymethyl ( Ethylene oxide addition of acrylamide compounds such as meth) acrylamide, dimethylaminoethyl (meth) acrylamide, N, N-dimethylaminopropylacrylamide, diacetoneacrylamide, dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate, and morpholin (meth). Nitrogen atom-containing (meth) acrylate compounds such as meth) acrylate, N-vinylpyrrolidone, N-vinylpyridine, N-vinylimidazole, N-vinylpyrrole, N-vinyloxazolidone, N-vinylsuccinimide, N-vinylmethylcarbamate , N, N-methylvinylacetamide, (meth) acryloyloxyethyltrimethylammonium chloride, 2-isopropenyl-2-oxazoline, 2-vinyl-2-oxazoline, (meth) acrylonitrile and the like.

Further, as the monomer constituting the acrylic resin, in addition to the above-mentioned (meth) acrylic acid ester monomer and the like, other monomers may be contained, if necessary. Such other monomers are particularly limited as long as they can be copolymerized with the above (meth) acrylic acid ester monomer and have desired water resistance and solvent resistance. Instead, it may be a monofunctional monomer having one ethylenically unsaturated double bond or a polyfunctional monomer having two or more ethylenically unsaturated double bonds. For example, vinyl monomers such as vinyl acetate, vinyl chloride, vinylidene chloride, vinyl fluoride, vinylidene fluoride, N-vinylpyrrolidone, vinylpyridine, N-vinylcarbazole, vinylimidazole, vinyl ether, vinylketone, vinylpyrrolidone; styrene, styrene Aromatic vinyl monomers such as α-, o-, m-, p-alkyl, nitro, cyano, amide, ester derivatives, vinyltoluene, chlorostyrene; olefin monomers such as ethylene, propylene, isopropylene; Diene monomer: A vinyl cyan compound monomer such as acrylonitrile or methacrylonitrile can be used. In addition, diacrylate compounds such as polyethaneglycol diacrylate, triethylene glycol diacrylate, and 1,3 monobutylene glycol diacrylate; triacrylate compounds such as trimethylolpropane triacrylate, trimethylol ethanetriacrylate, and tetramethylol methanetriacrylate. Dimethacrylate compounds such as ethylene glycol dimethacrylate, diethylene glycol dimethacrylate and triethylene glycol dimethacrylate; trimethacrylate compounds such as trimethylolpropane trimethacrylate and trimethylol ethanetrimethacrylate; divinylbenzene and the like can be used. The acrylic resin can be formed by using these monomers, but the form of the copolymerization of the monomers is not particularly limited, and may be, for example, a block copolymer, a random copolymer, a graft copolymer or the like. Can be done. The resin emulsion can be produced, for example, by subjecting it to an emulsion polymerization reaction and then neutralizing it after the reaction. As the emulsifier, a normal polymer-type surfactant may be used, or a reactive surfactant having an unsaturated bond may be used. The synthesis method is not particularly limited, but for example, in the presence of a reactive surfactant, a non-reactive surfactant, polyvinyl alcohol, a cellulose derivative, etc., polymerization of water, a monomer, an emulsifier, and the like is started. It can be emulsion-polymerized by mixing with an agent. The resin emulsion can also be obtained by mixing resin fine particles with water together with a surfactant without subjecting them to an emulsion polymerization reaction. For example, it can be obtained by adding (meth) acrylic acid ester or resin fine particles composed of styrene and (meth) acrylic acid ester and a surfactant to water and mixing them.

Examples of commercially available resin emulsions include Acryt WEM-031U, WEM-200U, WEM-321, WEM-3000, WEM-202U, WEM-3008, Acrylic-Urethane Resin Emulsion manufactured by Taisei Fine Chemicals Co., Ltd. UW-550CS, UW-223SX, AKW107, RKW-500 (manufactured by Taisei Fine Chemicals Co., Ltd., acrylic resin emulsion), LUBRIJET N240 (manufactured by Lubrizol, acrylic resin emulsion), Superflex 150, 210, 470, 500M, 620, 650, E2000, E4800, R5002 (manufactured by Daiichi Kogyo Seiyaku Co., Ltd., urethane resin emulsion), Viniblanc 701FE35, 701FE50, 701FE65, 700, 701, 711, 737, 747 (manufactured by Nissin Chemical Co., Ltd., PVC-acrylic) Resin emulsion), Viniblanc 2706, 2685 (Acrylic resin emulsion manufactured by Nisshin Chemical Co., Ltd.), Movin 743N, 6600, 7470, 7720, (Acrylic resin emulsion manufactured by Nippon Synthetic Chemical Co., Ltd.), and the like. However, it is not limited to these.

The average particle size of the resin emulsion is preferably 30 nm or more and 300 nm or less, and more preferably 50 nm or more and 250 nm or less, from the viewpoint of dispersion stability in the ink composition and inkjet ejection property. In this embodiment, the number average particle size of the pigment can be measured at a measurement temperature of 25 ° C. using a concentrated particle size analyzer (manufactured by Otsuka Electronics Co., Ltd., model: FPAR-1000).

The mass average molecular weight of the resin emulsion is preferably 10,000 or more and 1,000,000 or less, and more preferably 100,000 or more and 500,000 or less, from the viewpoint of stability of the ink composition and film water resistance. In this embodiment, the molecular weight of the resin indicates the mass average molecular weight Mw, which is a value measured by GPC (gel permeation chromatography) and is a value measured by "HLC-8120 GPC" manufactured by Toso Co., Ltd. , Polystyrene standard for calibration curve can be used as a standard for measurement.

Since the glass transition point (Tg) of the resin emulsion can form a printed matter having water resistance, solvent resistance and scratch resistance even when printed on a low-absorbency recording medium or a non-absorbent recording medium, it is also possible to form a printed matter. Since it is possible to avoid applying a high temperature to form a printed matter, it does not require a lot of energy, and the printed matter can be made less susceptible to heat damage, it is 0 ° C. or higher and 100 ° C. or lower. Is preferable, 10 ° C. or higher and 90 ° C. or lower is more preferable, and 20 ° C. or higher and 80 ° C. or lower is more preferable. The glass transition temperature (Tg) can be measured by, for example, a differential scanning calorimeter "DSC-50" manufactured by Shimadzu Corporation.

The resin emulsion is not limited to any of cationic, nonionic, and anionic properties, but the acid value of the resin emulsion is 25 mgKOH / g from the viewpoint of water resistance of printed matter, storage stability of ink composition, and the like. The following is preferable.

In the water-based inkjet recording ink composition of the present embodiment, if the mass part of the resin (resin emulsion) contained in 100 parts by mass of the ink composition can form a printed matter having desired water resistance and solvent resistance. Although not particularly limited, for example, it is preferably in the range of 0.05 parts by mass or more and 20 parts by mass or less in the ink composition, and in particular, within the range of 0.1 parts by mass or more and 20 parts by mass or less. It is preferably in the range of 0.5 parts by mass or more and 20 parts by mass or less, and more preferably in the range of 1 part by mass or more and 15 parts by mass or less.

[Surfactant]
In the water-based inkjet recording ink composition of the present embodiment, a surfactant may be contained as another additive. The surfactant that can be used in the aqueous inkjet recording ink composition of the present embodiment is not particularly limited, but for example, a polysiloxane compound, an anionic surfactant, a nonionic surfactant, and fluorine. Examples thereof include a based surfactant, an alkylene oxide-modified acetylene glycol-based surfactant, and an alkylene oxide non-modified acetylene glycol-based surfactant.

In the water-based inkjet recording ink composition of the present embodiment, any one of an alkylene oxide non-modified acetylene glycol-based surfactant, an alkylene oxide-modified acetylene glycol-based surfactant, and a polysiloxane compound is used as a surface tension adjusting agent. It is preferable to include the ink as an ink because it can improve the wettability and spreadability of the ink with respect to the recording medium.

Specific examples of the alkylene oxide non-modified acetylene glycol-based surfactant include 2,5-dimethyl-3-hexyne-2,5-diol, 3,6-dimethyl-4-octyne-3,6-diol, and the like. 2,4,7,9-Tetramethyl-5-decyne-4,7-diol, 3,5-dimethyl-1-hexyne-3-ol, 3-methyl-1-butyne-3-ol, 3-methyl Examples thereof include -1-pentyne-3-ol, 3-hexyne-2,5-diol, 2-butyne-1,4-diol and the like. Further, as a commercially available product, Surfinol 61, 82, 104 (all manufactured by Air Products Co., Ltd.) and the like can be used.

Specific examples of the alkylene oxide-modified acetylene glycol-based surfactant include Surfinol 420, 440, 465, 485, TG, 2502, Dynol 604, 607 (all manufactured by Air Products), Surfinol SE, and MD. -20, Orfin E1004, E1010, PD-004, EXP4300, PD-501, PD-502, SPC (all manufactured by Nissin Chemical Industry Co., Ltd.), acetylenol EH, E40, E60, E81, E100, E200 (all In each case, Kawaken Fine Chemical Co., Ltd.) and the like can be mentioned.

Commercially available polysiloxane compounds include, for example, FZ-2122, FZ-2110, FZ-7006, FZ-2166, FZ-2164, FZ-7001, FZ-2120, SH 8400, FZ-7002, FZ-2104. , 8029 ADDITIVE, 8032 ADDITIVE, 57 ADDITIVE, 67 ADDITIVE, 8616 ADDITIVE (all manufactured by Toray Dow Corning), KF-6012, KF-6015, KF-6004, KF-6013, KF-6011, KF-6043. , KP-104, 110, 112, 323, 341, (all manufactured by Shin-Etsu Chemical Co., Ltd.), BYK-300 / 302, BYK-301, BYK-306, BYK-307, BYK-320, BYK-325 , BYK-330, BYK-331, BYK-333, BYK-337, BYK-341, BYK-342, BYK-344, BYK-345 / 346, BYK-347, BYK-348, BYK-349, BYK-375 , BYK-377, BYK-378, BYK-UV3500, BYK-UV3510, BYK-310, BYK-315, BYK-370, BYK-UV3570, BYK-322, BYK-323, BYK-3455, BYK-Silceran3700 Also manufactured by Big Chemie), Silface SAG503A, Silface SJM-002, Silface SJM-003 (all manufactured by Nisshin Kagaku Kogyo Co., Ltd.), TEGO Twin 4000, TEGO Twin 4100, TEGO Wet 240, TEGO Wet 250, TEGO Wet 240, (all manufactured by Ebonic) and the like can be mentioned. These additives can be used in both the water-based inkjet recording ink composition and the oil-based inkjet recording ink composition described later. In the present invention, among them, a polyether group-modified polysiloxane compound having a polyether group can be preferably used.

Specific examples of anionic surfactants, nonionic surfactants, fluorine-based surfactants, and alkylene oxide-modified acetylene glycol-based surfactants include Emar, Latemul, Neoperex, and Demol (all anions). Surfactants; Sannoll, Liporan, Leipon, Lipearl (all anionic surfactants; manufactured by Lion Co., Ltd.), Neugen, Epan, Solgen (all nonionic surfactants; No. 1 Emargen, Amit, Emazole (all nonionic surfactants; manufactured by Kao Co., Ltd.), Naroacty, Emalmin, Sannonic (all nonionic surfactants; manufactured by Sanyo Kasei Kogyo Co., Ltd.) ), Megafuck (fluorosurfactant; manufactured by DIC Co., Ltd.), Surfron (fluorosurfactant; manufactured by AGC Seimi Chemical Co., Ltd.), AEROSOL TR-70, TR-70HG, OT manufactured by Nippon Cytec Industries Co., Ltd. -75, OT-N, MA-80, IB-45, EF-800, A-102, Perex OT-P manufactured by Kao Co., Ltd., Perex CS, Perex TR, Perex TA, New Call manufactured by Nippon Embroidery Co., Ltd. 290-A, Newcol 290-KS, Newcol 291-M, Newcol 291-PG, Newcol 291-GL, Newcol 292-PG, Newcol 293, Newcol 297 (all are anionic surfactants) ), Kao Co., Ltd. Emargen 320P, Emargen 350, Emargen 430, Emargen 130K, Emargen 150 Daiichi Kogyo Seiyaku Co., Ltd. Neugen TDS-120, Neugen TDS-200D, Neugen TDS-500F, Aoki Oil & Fat Industry Co., Ltd. -715, Brownon SR-720, Brownon SR-730, Brownon SR-750, Brownon EN-1520A, Brownon EN-1530, Brownon EN-1540, Newcol 2310, Newcol 2320, Newcol 2327, manufactured by Nippon Embroidery Co., Ltd. Examples thereof include Newcol 1545, Newcol 1820, NIKKOL BPS20 manufactured by Nikko Chemicals Co., Ltd., NIKKOL BPS30 (all are nonionic surfactants) and the like. The content of these surfactants is appropriately adjusted according to the content of the solvent, resin, pigment and other surfactants. Further, these surfactants may be used alone or in combination of two or more. The content of the surfactant is appropriately adjusted according to the ink mixability, cleanability, wettability to the inner wall of the flow path, and inkjet ejection property, and is preferably 0.05% by mass or more and 5% by mass in the total amount of the ink composition. Hereinafter, it is more preferably contained in an amount of 0.5% by mass or more and 3% by mass or less. In addition, these surfactants can be suitably used in an ink composition for water-based inkjet recording.

[Manufacturing method of ink composition for water-based inkjet recording]
In the method for producing an ink composition for water-based inkjet recording of the present embodiment, for example, by purifying the solvent represented by the general formula (1), the content of impurities is less than 1.0% by mass in the total amount of the solvent. An ink composition is prepared by mixing a purification step of obtaining a solvent represented by the following general formula (1), a coloring material, a resin, and a solvent represented by the following general formula (1) after the purification step. Examples thereof include an ink composition adjusting step for adjusting and a method for producing an ink composition including.

<Refining process>
In the purification step according to the present embodiment, a conventional purification method for obtaining a solvent represented by the following general formula (1) in which the content of impurities is less than 1.0% by mass in the total amount of the solvent is, for example, a conventional commercially available general. Distillation is repeated for the solvent represented by the formula (1), the step size of the distillation temperature is reduced so that impurities are not contained as much as possible, extraction is repeated, and the like, and in the industrial manufacturing process, the above-mentioned In addition to the above steps, it can be realized by further taking measures to suppress the contamination and the like.

<Ink composition adjustment process>
The preparation method in the ink composition adjusting step according to the present embodiment is not particularly limited as long as it is a method of mixing the coloring material, the resin, and the solvent represented by the general formula (1) after the purification step. For example, a method for preparing by adding a solvent, water, a pigment, a resin, a surfactant and other components as necessary, which are represented by the general formula (1) after the above-mentioned purification step, and after the above-mentioned purification step. A method of preparing by adding a pigment and a dispersant to a mixed solvent of a solvent represented by the general formula (1) and water, and then adding a resin, a surfactant and, if necessary, other components. After adding a pigment, a resin, a surfactant and, if necessary, other components to a mixed solvent of a solvent represented by the general formula (1) and water after the above purification step, the pigment is dispersed and prepared. The method and the like can be mentioned.

[Recording medium used for water-based inkjet recording ink composition]
In the inkjet recording method using the water-based inkjet recording ink composition of the present embodiment, the recording medium is not particularly limited, and any of an absorbent recording medium, a low absorbency recording medium, and a non-absorbent recording medium is preferably used. be able to. Examples of the absorbent recording medium include non-coated paper such as stencil paper, medium-quality paper, wood-free paper, and copy paper (PCC); cloths such as cotton, synthetic fiber woven fabric, silk, linen, and non-woven fabric. The absorbability of the recording medium is, for example, the JAPAN TAPPI pulp and paper test method No. The test can be performed at 51-87 and the like. Uncoated paper has high absorbency because it is not coated with a coating agent that reduces the penetration and absorption of ink. Examples of the low-absorbency base material include finely coated paper, lightweight coated paper, coated paper, art paper, coated paper such as cast paper, and the like. Coated paper is a paper in which a coating liquid prepared by adding a white pigment or a binder component is applied to improve surface smoothness, and the ink composition is difficult to be absorbed and penetrated. Examples of the non-absorbent base material include plastic films such as polyester-based resin, polypropylene-based resin, vinyl chloride resin, and polyimide resin; metal, metal-deposited paper, glass, synthetic rubber, natural rubber, leather, and the like. Be done.

[Recording method using an ink composition for water-based inkjet recording]
The inkjet recording method using the ink composition of the present embodiment (hereinafter, may be simply referred to as an inkjet recording method) is not particularly limited, but for example, the ink jet method is used on a recording medium. An inkjet recording method for applying the ink composition of the embodiment can be mentioned. By using the ink composition of the present embodiment, it is possible to realize an inkjet recording method having good member suitability for an inkjet head and an inkjet recording device and excellent maintainability. Further, since the ink composition of the present embodiment has good ejection stability, dryness of the printed matter, and blocking resistance, the productivity of the printed matter using the inkjet recording method can be improved. Further, since the ink composition of the present embodiment has a low odor, it is possible to reduce the risk of harming the health of the worker who performs inkjet recording.

The ink composition of the present embodiment can be applied to any of the inkjet recording devices such as the piezo method, the thermal method, and the electrostatic method, but among them, agglomerates are less likely to be generated and the ejection stability is excellent. , It is preferable to be used for a piezo type inkjet recording device. The piezo type recording head uses a piezoelectric vibrator as a pressure generating element, and pressurizes and depressurizes the pressure chamber by deformation of the piezoelectric vibrator to eject ink droplets. The format of the inkjet printing method is not particularly limited, and may be a serial head type inkjet method or a line head type inkjet method.

[Method for manufacturing printed matter using an ink composition for water-based inkjet recording]
A printed matter can also be produced by using the above-mentioned inkjet recording method. In the method for producing a printed matter of the present invention, by using the water-based inkjet recording ink composition of the present embodiment, the ink composition has good ejection stability, dryness and blocking resistance of the printed matter, and has a low odor. Therefore, high quality printed matter can be obtained.

Next, an ink composition for oil-based inkjet recording, which is another embodiment of the present invention, will be described.

<Ink composition for oil-based inkjet recording>
[Solvent represented by the general formula (1)]
The oil-based inkjet recording ink composition of the present embodiment does not contain water, contains an organic solvent as a main component, and contains a solvent represented by the general formula (1) (hereinafter, simply referred to as simple). It may be referred to as an ink composition for oil-based inkjet recording). In the oil-based inkjet recording ink composition of the present embodiment, "water-free" means an ink composition produced without intentionally containing water, and is contained in, for example, the atmosphere. Water that is contained due to a cause not intended by the manufacturer, such as water vapor or water contained in the additive, is not considered.

In the oil-based ink jet recording ink composition of the present embodiment, the content of the entire ink composition of the solvent represented by the general formula (1) is in the range of 5% by mass or more and 95% by mass or less in the total amount of the ink composition. In particular, it is preferably in the range of 10% by mass or more and 90% by mass or less in the total amount of the ink composition, and particularly in the range of 20% by mass or more and 85% by mass or less in the total amount of the ink composition. It is preferable to have. As the solvent represented by the general formula (1), the same solvent as that used in the above-mentioned water-based inkjet recording ink composition can also be exemplified.

[Other solvents]
The oil-based inkjet recording ink composition of the present embodiment may contain a solvent other than the solvent represented by the general formula (1), if necessary. For example, it is a cyclic ester compound, and contains a lactone-based solvent in which a hydroxyl group and a carboxyl group in the same molecule are dehydrated and condensed to form a cyclic structure, or one carboxylic acid amide structure in the molecular structure, and the linear alkyl structure contains one. It may contain an amide-based solvent having an ether bond.

The lactone-based solvent is a solvent mainly composed of a vinyl chloride-based polymer and having particularly high permeability to the printed surface, and improves dryness, image reproducibility of fine lines, and abrasion resistance. Further, the lactone-based solvent has a property that it has a relatively slow drying property and is hard to volatilize, and has an advantage of improving discharge stability and intermittent discharge stability. The amide-based solvent also has high permeability to the printed surface mainly made of a vinyl chloride-based polymer, and improves dryness and abrasion resistance. On the other hand, the amide-based solvent does not easily volatilize on the surface of the head, and has the advantage of improving the fluidity of the ink, the ejection responsiveness, and the intermittent ejection stability.

As the solvent other than the solvent represented by the general formula (1), the lactone-based solvent, and the amide-based solvent, those conventionally used in the oil-based ink composition for inkjet recording are mainly used, and the ink for inkjet recording of the present invention is mainly used. It can be appropriately selected and used as long as the performance of the composition is not impaired.

[resin]
The oil-based inkjet recording ink composition of the present embodiment contains a resin. By containing the resin in the ink composition, the water resistance of the printed matter is improved. The resin is not particularly limited, and is, for example, acrylic resin, polystyrene resin, polyester resin, vinyl chloride resin, vinyl acetate resin, vinyl chloride vinyl acetate copolymer resin, polyethylene resin, urethane resin, rosin-modified resin, phenyl resin, terpen. Based resin, polyamide resin, vinyl toluene-α-methylstyrene copolymer, ethylene-vinyl acetate copolymer, cellulose acetate butyrate, silicone (silicon) resin, acrylamide resin, epoxy resin, or copolymer resins thereof A mixture can be used.

In the oil-based inkjet recording ink composition of the present embodiment, the acrylic resin is particularly effective in improving ejection responsiveness during high-speed printing, and improving ejection stability, water resistance, and solvent resistance. It is preferable that it contains.

The acrylic resin is not particularly limited as long as it is contained as the main component of the monomer constituting the (meth) acrylic acid ester monomer, and examples of the same as the above-mentioned water-based inkjet recording ink composition may be exemplified. can. The acrylic resin may be a homopolymer of one kind of radically polymerizable monomer, or may be any of a copolymers in which two or more kinds of radically polymerizable monomers are selected and used. The acrylic resin preferable as the form of the oil-based inkjet recording ink composition is at least selected from a polymer of methyl methacrylate alone or a group consisting of methyl methacrylate and butyl methacrylate, ethoxyethyl methacrylate, and benzyl methacrylate. It is a copolymer with one or more compounds.

Such an acrylic resin can provide an oil-based inkjet recording ink composition which exhibits good compatibility with a solvent in an ink and has storage stability and image reproducibility of the ink. The acrylic resin used in the present invention preferably has a mass average molecular weight of 5,000 or more and 100,000 or less. Above all, the acrylic resin used in the oil-based inkjet recording ink composition of the present embodiment preferably has a mass average molecular weight of 10,000 or more, and preferably 12,000 or more, from the viewpoint of abrasion resistance and blocking resistance. More preferably, it is more preferably 15,000 or more. On the other hand, the acrylic resin used in the oil-based inkjet recording ink composition of the present embodiment is preferably 50,000 or less, more preferably 35,000 or less, and more preferably 35,000 or less, from the viewpoint of high ejection stability during high-speed printing. Further, it is preferably 30,000 or less. The acrylic resin used in the oil-based inkjet recording ink composition of the present embodiment preferably has a glass transition temperature (Tg) of 80 ° C. or higher and 110 ° C. or lower. When Tg is within the above range, the effect of obtaining good print-drying property becomes remarkable. Examples of commercially available (meth) acrylic resins include "Paraloid B99N" (methyl methacrylate / butyl methacrylate copolymer) Tg 82 ° C., mass average molecular weight 15,000) and "Paraloid B60" (Paraloid B60) manufactured by Roam & Haas. Methyl methacrylate / butyl methacrylate copolymer) Tg 75 ° C., mass average molecular weight 50,000) and the like are exemplified.

Examples of the vinyl chloride vinyl acetate-based copolymer resin that can be used in the oil-based inkjet recording ink composition of the present embodiment include vinyl chloride vinyl acetate copolymer, vinyl chloride / vinyl acetate / maleic acid copolymer, and chloride. Examples thereof include vinyl / vinyl acetate / vinyl alcohol copolymers, vinyl chloride / vinyl acetate / hydroxyalkyl acrylate copolymers, and mixtures thereof. As the above-mentioned vinyl chloride-based copolymer resin chloride, "Solvine C (number average molecular weight (Mn), 31000), CL (Mn, 25000), CNL (Mn, 12000)," from Nisshin Chemical Industry Co., Ltd. CLL (Mn, 18000), C5R (Mn, 27000), TA2 (Mn, 33000), TA3 (Mn, 24000), A (Mn, 30000), AL (Mn, 22000), TA5R (Mn, 28000), M5 It can be obtained under a trade name such as (Mn, 32000) and used in the present invention.

In the oil-based inkjet recording ink composition of the present embodiment, the mass part of the resin contained in 100 parts by mass of the ink composition is not particularly limited, but is, for example, 0.05 parts by mass in the ink composition. It is preferably in the range of 20 parts by mass or less, particularly preferably in the range of 0.1 parts by mass or more and 20 parts by mass or less, and further in the range of 0.5 parts by mass or more and 20 parts by mass or less. It is preferably in the range of 1 part by mass or more and 15 parts by mass or less.

[Dispersant]
A dispersant may be used in the oil-based inkjet recording ink composition of the present embodiment, if necessary. As the dispersant, any dispersant used in the oil-based inkjet recording ink composition can be used. As the dispersant, a polymer dispersant may be used. As such a dispersant, the main chain is composed of polyester-based, polyacrylic-based, polyurethane-based, polyamine-based, polycaprolactone-based, etc., and the side chain has a polar group such as an amino group, a carboxyl group, a sulfone group, and a hydroxyl group. Is. Examples of polyacrylic dispersants include Disperbyk-2000, 2001, 2008, 2009, 2010, 2020, 2020N, 2022, 2025, 2050, 2070, 2095, 2150, 2151, 2155, 2163, 2164, BYKJET-9130, 9131. , 9132, 9133, 9151 (manufactured by BIC Chemie) are used. As the polycaprolactone-based dispersant, for example, azisper PB821, PB822, PB881 (manufactured by Ajinomoto Fine-Techno Co., Ltd.) are used. Preferred dispersants are polyester-based dispersants, such as Hinoact KF-1000, T-6000, T-7000, T-8000, T-8000E, T-9050 (manufactured by Kawaken Fine Chemicals Co., Ltd.), Solsperse 20000, and the like. 24000, 32000, 32500, 32550, 32600, 33000, 33500, 34000, 35200, 36000, 37500, 39000, 71000 (manufactured by Lubrizol), Floren DOPA-15BHFS, 17HF, 22, G-700, 900, NC-500. , GW-1500 (manufactured by Kyoeisha Chemical Co., Ltd.), Efka4310, 4320, 4330, 4401, 4402, 4403N, 4570, 7411, 7477, 7700 (manufactured by BASF) alone, or a mixture thereof can be used. Further, the same as the water-soluble polymer dispersant in the above-mentioned water-based inkjet recording ink composition can also be exemplified.

[Surfactant]
Further, in the oil-based inkjet recording ink composition of the present embodiment, volatilization suppression, solidification prevention, and resolubility when solidified of the oil-based inkjet recording ink composition in a device such as a nozzle portion or a tube are suppressed. In addition to the mixed solvent, a liquid nonionic polyoxyethylene derivative may be added at room temperature and atmospheric pressure. For example, nonionic P-208, P-210, P-213, E-202S, E-205S, E-215, K-204, K-220, S-207, S-215 which are polyoxyalkylene alkyl ethers. , A-10R, A-13P, NC-203, NC-207 (manufactured by Nippon Yushi Co., Ltd.), Emargen 106, 108, 707, 709, A-90, A-60 (manufactured by Kao Co., Ltd.), Floren G-70, D-90 (manufactured by Kyoeisha Chemical Co., Ltd.), Poem J-0081HV (manufactured by Riken Vitamin Co., Ltd.), Adecator NP-620, NP-650, NP-660, NP-675, NP-683, NP-686, Adecacol CS-141E, TS-230E (manufactured by Adeca Co., Ltd.), Sorgen 30V, 40, TW-20, TW-80, Neugen CX-100 (manufactured by Daiichi Kogyo Seiyaku Co., Ltd.), etc. Illustrated. Further, the same surfactants that can be used in the above-mentioned water-based inkjet recording ink composition can also be exemplified.

The surfactant is not limited to the above, and any anionic, cationic, amphoteric or nonionic surfactant may be used, and may be appropriately selected according to the purpose of addition.

[Manufacturing method of ink composition for oil-based inkjet recording]
In the method for producing an oil-based ink composition for ink-based inkjet recording of the present embodiment, for example, by purifying the solvent represented by the general formula (1), the content of impurities is less than 1.0% by mass in the total amount of the solvent. An ink composition is prepared by mixing a purification step of obtaining a solvent represented by the following general formula (1), a coloring material, a resin, and a solvent represented by the following general formula (1) after the purification step. Examples thereof include an ink composition adjusting step for adjusting and a method for producing an ink composition including.

<Refining process>
The purification step can be realized by the same method as the purification step in the above-mentioned method for producing an ink composition for water-based inkjet recording.

[Preparation method of ink composition for oil-based inkjet recording]
The preparation method in the ink composition adjusting step according to the present embodiment is not particularly limited as long as it is a method of mixing a coloring material, a resin, and a solvent represented by the general formula (1) after the purification step. For example, first, a part or all of the solvent represented by the general formula (1) after the above purification step is mixed to obtain a solvent in an oil-based ink jet recording ink composition. For example, when a dispersant is used, a coloring material and a dispersant are added to the solvent, and the color material dispersion liquid is prepared by mixing and dispersing with a ball mill, a bead mill, ultrasonic waves, a jet mill, or the like. It is obtained by adding the remainder of the solvent obtained above, a resin, and other additives to the obtained color material dispersion liquid under stirring.

[Recording medium used for oil-based inkjet recording ink composition]
In the inkjet recording method using the oil-based ink composition for inkjet recording of the present embodiment, a recording medium mainly made of a resin is preferably used as a recording medium, and the resin is a polyvinyl chloride polymer or acrylic. , PET, polycarbonate, PE, PP and the like are used. In particular, it is suitable for recording on a recording medium whose printing surface is made of a hard or soft polyvinyl chloride polymer. As a recording medium whose printing surface is made of a polyvinyl chloride polymer, a polyvinyl chloride base material (film or sheet) or the like can be exemplified.

[Recording method using an ink composition for oil-based inkjet recording]
The inkjet recording method using the oil-based inkjet recording ink composition of the present embodiment is an inkjet recording method in which ink is ejected by an inkjet method to record on a recording medium, and the ink composition is an oil-based inkjet recording ink. It is characterized by using a composition. A preferred method is an inkjet recording method in which recording is performed on a recording medium using an inkjet recording device equipped with an inkjet head cleaning system. By using the ink composition of the present embodiment, it is possible to realize an inkjet recording method having good member suitability for an inkjet head and an inkjet recording device and excellent maintainability. Further, since the ink composition of the present embodiment has good ejection stability, dryness of the printed matter, and blocking resistance, the productivity of the printed matter using the inkjet recording method can be improved. Further, since the ink composition of the present embodiment has a low odor, it is possible to reduce the risk of harming the health of the worker who performs inkjet recording.

The inkjet recording method according to the present embodiment can be applied to any of the inkjet recording devices provided with a conventionally known inkjet head cleaning system. Above all, it can be preferably applied to an inkjet recording apparatus provided with a cleaning system having at least a configuration for sucking ink remaining or clogged in the nozzle of the inkjet head. Further, it is preferably used for an inkjet recording device provided with a cleaning system in which a flexible liquid feeding tube made of an elastomer or the like is used for connecting a liquid feeding pump or the like.

[Manufacturing method of printed matter used for oil-based inkjet recording ink composition]
A printed matter can also be produced by using the above-mentioned inkjet recording method. In the method for producing a printed matter of the present invention, by using the oil-based ink jet recording ink composition of the present embodiment, the ink composition has good ejection stability, dryness and blocking resistance of the printed matter, and has a low odor. Therefore, high quality printed matter can be obtained.

Hereinafter, the present invention will be described in more detail by way of examples, but the present invention is not limited to these descriptions.

<Adjustment of ink composition for water-based inkjet recording>
Examples 1 and 2 and Comparative Examples 1 and 2 as described below using a coloring material (pigment dispersion), a resin (resin emulsion), a solvent represented by the following general formula (1), and water (ion-exchanged water). The ink composition of was adjusted. The method for adjusting the pigment dispersion and the resin (resin emulsion) is shown below.

1. 1. Adjustment of Pigment Dispersion A pigment dispersant was prepared by the following method.

In 200 g of toluene kept at 100 ° C., 63 g of methyl methacrylate, 27 g of butyl acrylate, 30 g of butyl methacrylate, 15 g of acrylic acid, 15 g of methacrylic acid, and 3.6 g of tert-butylperoxy-2-ethylhexanoate. The mixture was added dropwise over 1.5 hours. After completion of the dropping, the mixture was reacted at 100 ° C. for 2 hours and then cooled to obtain a resin solution. The resin was purified from the resin solution with hexane to obtain a pigment dispersant having a molecular weight of 20000 and an acid value of 143 mgKOH / g.

2.5 g of the pigment dispersion resin obtained above and 0.6 g of N, N-dimethylaminoethanol were dissolved in 80 g of water (ion-exchanged water), and C.I. I. Pigment 122 and an antifoaming agent (“Surfinol 104PG” manufactured by Air Products Co., Ltd.) were added in an amount of 0.05 g and dispersed with a paint shaker using zirconia beads to obtain a pigment dispersion.

2. 2. Adjustment of resin emulsion After sufficiently replacing the inside of the flask equipped with a mechanical stirrer, thermometer, nitrogen gas introduction tube, reflux tube and dropping funnel with nitrogen gas, a reactive surfactant (manufactured by Kao Co., Ltd., trade name) : Latemul PD-104) 0.75 g, potassium persulfate 0.04 g, methacrylic acid 1.5 g and pure water 150 g were charged, and stirred and mixed at 25 ° C. A mixture of 115.5 g of methyl methacrylate, 18 g of 2-ethylhexyl acrylate, and 15 g of butyl acrylate was added dropwise thereto to prepare a pre-emulsion. Further, after sufficiently replacing the inside of the flask equipped with a mechanical stirrer, a thermometer, a nitrogen gas introduction tube, a perfusion tube and a dropping funnel with nitrogen gas, a reactive surfactant (manufactured by Kao Co., Ltd., trade name: Latemul) PD-104) 3 g, potassium persulfate 0.01 g and pure water 200 g were stirred and mixed at 70 ° C. Then, the prepared pre-emulsion was added dropwise into the flask over 3 hours. After further heating and aging at 70 ° C. for 3 hours, the mixture is cooled, adjusted to pH 8 with N, N-dimethylethanolamine, filtered through a # 150 mesh (manufactured by Nippon Textile), and has a solid content of 30% by mass, 500 g. Resin emulsion (glass transition temperature 64 ° C., acid value 7 mgKOH / g average particle diameter 90 nm) was obtained.

3. 3. Purification of solvent represented by the general formula (1) Purification by distillation and purification of commercially available triethylene glycol monobutyl ether (impurity content: 2.4% by mass), hereinafter referred to as TEGMBE-B). , Purified triethylene glycol monobutyl ether (hereinafter referred to as TEGMBE-A) was obtained.

In addition, TEGMBE-A is gas chromatographed based on JIS K0114 (device name: Agent 7890B / 5977A GC / MSD manufactured by Azilent Technology Co., Ltd .: (detection limit 0.1% by mass) or less, method for solvent composition analysis. When the solvent composition was analyzed by the same method, diethylene glycol monobutyl ether (boiling point: 230 ° C.) was 0.4% by mass, tetraethylene glycol monobutyl ether (boiling point: 304 ° C.) was 0.2% by mass, and diethylene glycol was analyzed. It was confirmed that (boiling point 245 ° C.) was contained in 0.2% by mass, respectively (the impurities derived from the solvent represented by the general formula (1) are the total amount of the solvent represented by the general formula (1). Medium 0.8% by mass).

When the solvent composition of TEGMBE-B was analyzed, diethylene glycol monobutyl ether (boiling point: 230 ° C.) was 0.5% by mass, tetraethylene glycol monobutyl ether (boiling point: 304 ° C.) was 0.7% by mass, and diethylene glycol was analyzed. (Boiling point: 245 ° C.) is 0.3% by mass, triethylene glycol (boiling point: 285 ° C.) is 0.4% by mass, ethylene glycol (boiling point: 198 ° C.) is 0.2% by mass, and ethylene glycol monoethyl ether (boiling point: boiling point). : 135 ° C.) was confirmed to be contained in 0.1% by mass, dibutyl ether (boiling point 142 ° C.) in 0.1% by mass, and 1-butanol (boiling point: 117 ° C.) in 0.1% by mass. (The amount of impurities derived from the solvent represented by the general formula (1) is 2.4% by mass based on the total amount of the solvent represented by the general formula (1)).

A commercially available tripropylene glycol monomethyl ether (impurity content: 2.5% by mass, hereinafter referred to as TPGMME-B) is purified in the same manner as the above TEGMBE, and the purified tripropylene glycol monomethyl ether (hereinafter referred to as TPGMME-A) is purified. (Notation) was obtained.

When the solvent composition of TPGMME-A was analyzed, the impurities derived from the solvent represented by the general formula (1) were dipropylene glycol monomethyl ether (boiling point 187 ° C.) in an amount of 0.4% by mass and tripropylene glycol dimethyl ether ( It was confirmed that 0.5% by mass (boiling point 215 ° C.) was contained (the impurities derived from the solvent represented by the general formula (1) are contained in the total amount of the solvent represented by the general formula (1). 0.9% by mass).

When the solvent composition of TPGMME-B was analyzed, as impurities derived from the solvent represented by the general formula (1), dipropylene glycol monomethyl ether (boiling point 187 ° C.) was 1.0% by mass, and tripropylene glycol dimethyl ether ( 215 ° C.) is 0.8% by mass, tetrapropylene glycol monomethyl ether (boiling point: 330 ° C.) is 0.2% by mass, propylene glycol dimethyl ether (97 ° C.) is 0.2% by mass, and propylene glycol monomethyl ether (boiling point). It was confirmed that 0.2% by mass of (120 ° C.) and 0.1% by mass of methanol (boiling point: 65 ° C.) were contained (the impurities derived from the solvent represented by the general formula (1) are 2.5% by mass of the total amount of solvent).

4. Preparation of ink composition for water-based inkjet recording Pigment dispersion, resin emulsion, propylene glycol, solvent represented by the general formula (1), polysiloxane compound (Silface SAG503A manufactured by Nissin Chemical Industry Co., Ltd.), water (ion) The ink compositions of Examples and Comparative Examples were prepared as shown in Table 1 below using the exchanged water (denoted as water in Table 1). The numerical values of "pigment dispersant" and "resin emulsion" in the table represent the amount as a solid content. The numbers in the table mean mass (unit is mass part) unless otherwise specified, but the "impurities in the total amount of the ink composition" in the table are the general formula (1) in the total amount of the ink composition. It means the mass% of impurities derived from the represented solvent.

<Adjustment of oil-based inkjet recording ink composition>

1. 1. Purification of solvent represented by general formula (1) (1) Three types of commercially available diethylene glycol diethyl ether Diethylene glycol diethyl ether 1 (Contents of impurities derived from solvent represented by general formula (1): 1.9 mass %, Hereinafter referred to as DEGDEE-D)
Diethylene glycol diethyl ether 2 (content of impurities derived from solvent represented by general formula (1): 2.3% by mass, hereinafter referred to as DEGDEE-E)
Diethylene glycol diethyl ether 3 (content of impurities derived from solvent represented by general formula (1): 2.5% by mass, hereinafter referred to as DEGDEE-F)

(2) Diethylene glycol diethyl ether obtained by purifying commercially available diethylene glycol diethyl ether in the same manner as the above TEGMBE Diethylene glycol diethyl ether 4 (hereinafter referred to as DEGDEE-A).
Diethylene glycol diethyl ether 5 (hereinafter referred to as DEGDEE-B)
Diethylene glycol diethyl ether 6 (hereinafter referred to as DEGDEE-C)
Got

When the solvent composition of DEGDEE-A was analyzed, impurities derived from the solvent represented by the general formula (1) were not detected (impurities derived from the solvent represented by the general formula (1) were contained in the total amount of the solvent. Less than 0.1% by mass).

When the solvent composition of DEGDEE-B was analyzed, ethylene glycol diethyl ether (boiling point: 121 ° C.) was 0.1% by mass, and diethylene glycol methyl ethyl ether was used as an impurity derived from the solvent represented by the general formula (1). It was confirmed that (boiling point 176 ° C.) was 0.2% by mass, diethylene glycol monoethyl ether (boiling point 202 ° C.) was 0.2% by mass, and ethoxyethanol (boiling point 135 ° C.) was 0.1% by mass. (The amount of impurities derived from the solvent represented by the general formula (1) is 0.6% by mass based on the total amount of the solvent represented by the general formula (1)).

When the solvent composition of DEGDEE-C was analyzed, diethylene glycol (boiling point of 245 ° C.) was 0.2% by mass and diethylene glycol monoethyl ether (boiling point of 202 ° C. was 202 ° C.) as impurities derived from the solvent represented by the general formula (1). ) Was confirmed to be contained in an amount of 0.2% by mass and triethylene glycol (boiling point of 285 ° C.) was contained in an amount of 0.1% by mass. 0.5% by mass in the total amount of the solvent represented by the formula (1)).

When the solvent composition of DEGDEE-D was analyzed, ethylene glycol monoethyl ether (boiling point 135 ° C.) was 0.6% by mass, and diethylene glycol monoethyl was found as an impurity derived from the solvent represented by the general formula (1). Ether (boiling point 202 ° C.) is contained in 0.5% by mass, ethylene glycol diethyl ether (boiling point 121 ° C.) is contained in 0.6% by mass, and ethoxyethanol (boiling point 135 ° C.) is contained in 0.2% by mass. Confirmed (the amount of impurities derived from the solvent represented by the general formula (1) is 1.9% by mass based on the total amount of the solvent represented by the general formula (1)).

When the solvent composition of DEGDEE-E was analyzed, diethylene glycol monomethyl ether (boiling point of 194 ° C.) was 1.0% by mass, and ethylene glycol monoethyl ether was used as an impurity derived from the solvent represented by the general formula (1). It was confirmed that (boiling temperature 135 ° C.) was 1.0% by mass and ethoxyethanol (boiling point 135 ° C.) was 0.3% by mass (the impurities derived from the solvent represented by the general formula (1) are , 2.3% by mass in the total amount of the solvent represented by the general formula (1)).

When the solvent composition of DEGDEE-F was analyzed, as impurities, tetraethylene glycol diethyl ether (boiling point 300 ° C.) was 1.0% by mass, triethylene glycol (boiling point 285 ° C.) was 1.0% by mass, and diethylene glycol was used. It was confirmed that (boiling point 245 ° C.) was contained in an amount of 0.5% by mass (the impurities derived from the solvent represented by the general formula (1) are contained in the total amount of the solvent represented by the general formula (1). 2.5% by mass).

Commercially available diethylene glycol methyl ethyl ether (hereinafter referred to as DEGMEE-C) was purified in the same manner as the above TEGMBE to obtain purified diethylene glycol methyl ethyl ether (hereinafter referred to as DEGMEE-A and DEGMEE-B).

When the solvent composition of DEGMEE-A was analyzed, impurities derived from the solvent represented by the general formula (1) were not detected (impurities derived from the solvent represented by the general formula (1) are solvents. Less than 0.1% by mass in the total amount).

When the solvent composition of DEGMEE-B was analyzed, diethylene glycol diethyl ether (boiling point 189 ° C.) was 0.3% by mass and diethylene glycol dimethyl ether (boiling point 162) as impurities derived from the solvent represented by the general formula (1). It was confirmed that 0.3% by mass of diethylene glycol monoethyl ether (boiling point 202 ° C.) and 0.2% by mass of diethylene glycol monomethyl ether (boiling point 194 ° C.) were contained (general). The amount of impurities derived from the solvent represented by the formula (1) is 0.9% by mass in the total amount of the solvent).

When the solvent composition of DEGMEE-C was analyzed, triethylene glycol (boiling point of 285 ° C.) was 0.2% by mass, and ethylene glycol monoethyl ether was used as an impurity derived from the solvent represented by the general formula (1). 0.2% by mass (boiling point 135 ° C.), 0.2% by mass of ethylene glycol dimethyl ether (boiling point 98 ° C.), 0.2% by mass of ethylene glycol monomethyl ether (boiling point 124 ° C.), diethylene glycol dimethyl ether (boiling point 162 ° C.) Is contained in 0.5% by mass, diethylene glycol monomethyl ether (boiling point 194 ° C.) is contained in 0.3% by mass, ethoxyethanol (boiling point 135 ° C.) is contained in 0.2% by mass, and ethanol (boiling point 78 ° C.) is contained in 0.1% by mass. (The amount of impurities derived from the solvent represented by the general formula (1) is 1.9% by mass in the total amount of the solvent).

2. 2. Resin adjustment (1) Acrylic resin 1
A mixture of 200 g of methyl methacrylate and 6.3 g of t-butylperoxy-2-ethylhexanoate was added dropwise to 300 g of DEGDEE-A kept at 100 ° C. over 1.5 hours. After completion of the dropping, the mixture was reacted at 100 ° C. for 2 hours and then cooled to obtain a colorless and transparent polymer solution of methyl methacrylate (solid content: 39.5%). The Tg of the obtained polymer (denoted as acrylic resin 1 in the table) was 105 ° C. When GPC measurement was performed, the mass average molecular weight was 18,000.

(2) Acrylic resin 2
Using a mixture of 180 g of methyl methacrylate, 20 g of n-butyl methacrylate and 3.6 g of t-butylperoxy-2-ethylhexanoate, a colorless and transparent methyl methacrylate is used by the same synthesis method as that of acrylic resin 1. A copolymer solution of n-butyl methacrylate (solid content: 39.8%) was obtained. The Tg of the obtained polymer (denoted as acrylic resin 2 in the table) was 94 ° C., and the mass average molecular weight was 30,000.

(3) Vinyl Chloride-Vinyl Acetate Resin As the vinyl chloride-vinyl acetate resin, trade name Solvine CLL (mass average molecular weight 18000, manufactured by Nisshin Kagaku Kogyo Co., Ltd.) was used (indicated as vinyl chloride resin in the table).

3. 3. Preparation of oil-based ink composition for inkjet recording Resin (acrylic resin 1, 2, vinyl chloride-vinyl acetate resin), Bk pigment (Carbon Black (MA-8, manufactured by Mitsubishi Chemical Corporation, Table 2, Table 3 Bk pigment) (Notated as C pigment), C pigment (P.B. 15: 4) (Cyanine blue, manufactured by Dainichi Seika Kogyo Co., Ltd., indicated as C pigment in Tables 2 and 3), M pigment (P.Y. 155) ( FASTGEN SUPER MAGENTA RG, manufactured by DIC Co., Ltd., referred to as M pigment in Tables 2 and 3)), solvent represented by the above general formula (1), amide solvent (Equamid M100 (manufactured by Idemitsu Kosan Co., Ltd.), Table 2, Table 3 EM100), lactone solvent (γ-butyrolactone, Table 2, Table 3, GBLO), Additive A (Floren D-90 (Kyoeisha Chemical Co., Ltd. nonionic surface activity) The ink compositions of Examples and Comparative Examples were prepared as shown in Tables 2 and 3 below using the agent)) and the additive B (BYK-333 (polysiloxane-based surfactant manufactured by Big Chemie)). The numerical values of the pigments (Bk pigment, C pigment, M pigment) and the resin (acrylic resin 1, acrylic resin 2, salt vinegar biresin) in the table represent the amount as a solid content, and the unit is an ink composition. It is a mass part in 100 parts by mass.

<Evaluation>
Each evaluation was performed on the ink compositions of the above Examples and Comparative Examples. In the evaluation criteria, the evaluation A is superior to the conventional one or has no practical problem, and the evaluation B is superior to the conventional one or has a practical problem.

(1) Odor test An odor test was performed on the ink compositions of Examples and Comparative Examples. Specifically, a recording medium (polyvinyl chloride film (IMAGin JT5829R: MACtac) is used by an inkjet method using an inkjet printer (trade name: VersaArt RE-640, manufactured by Roland DG Co., Ltd.) using the ink composition as a printer). The printed matter immediately after printing in (manufactured by the company)) was sensually evaluated according to the following criteria by having five subjects smell the printed matter. When the majority evaluation was A, it was evaluated as A, and similarly, it was evaluated as B and C (indicated as "odor" in the table).
Evaluation A: There is no unpleasant odor or there is a weak odor, but there is no problem in practical use.
Evaluation B: There is an unpleasant strong odor.

(2) Printer member aptitude test 1 (adhesive for head)
Examples and Comparative Examples were 0.2 g of a cured product obtained by drying an epoxy adhesive (two-component curable epoxy adhesive “1500”, manufactured by Cemedine Co., Ltd.) used for a member of an inkjet head at 60 ° C. for 1 day. The ink composition was immersed in the ink composition of No. 1 and left at 60 ° C. for 1 week to perform an immersion test, and the weight change of the cured product was measured (indicated as "member suitability 1" in the table).
Evaluation A: The rate of change in weight is less than 8%, and there is no deterioration of the material.
Evaluation B: Weight change rate is 8% or more, or the material is deteriorated.

(3) Printer member aptitude test 2 (absorber for head cap)
Ink absorber PVA sponge used for head cap member of inkjet head (“Belle Eater (A)”, manufactured by Fuji Chemical Co., Ltd.) 1 cm × 2 cm × 1 mm for 7 days in the ink compositions of Examples and Comparative Examples. After immersing and drying, deformation and deterioration of the absorber were confirmed (indicated as "member suitability 2" in the table).
Evaluation A: The volume change rate is less than 20%, and there is no deterioration of the material.
Evaluation B: The volume change rate is 20% or more, or the material is deteriorated.

(4) Discharge Stability Test Using the ink compositions of Examples and Comparative Examples with the above printer, fine lines are printed on the above recording medium in a bidirectional high-speed printing mode (360 x 360 dpi), and visually confirmed and evaluated. (Indicated as "discharge stability" in the table).
Evaluation A: The thin lines are reproduced correctly.
Evaluation B: The landing position is greatly deviated, and bending is observed.

(5) Intermittent ejection test The printer was filled with the ink compositions of Examples and Comparative Examples, and intermittent printing was performed on the recording medium at room temperature for a long period of time, resulting in missing dots and flight bending. In addition, the presence or absence of ink splattering was observed, and the number of occurrences was counted and evaluated (indicated as "intermittent ejection property" in the table).
Evaluation A: Within the test period of 24 hours, the occurrence of missing dots, flight bending, or ink splattering was less than 30 times.
Evaluation B: Within the test period of 24 hours, the occurrence of missing dots, flight bending, or ink splattering was 30 times or more.

(6) Cleaning recovery test As one of the evaluations of maintainability, it was evaluated whether the nozzle clogging can be cleared by the cleaning operation of the printer when the nozzle clogging in the head occurs.
Specifically, using the above printer equipped with a cleaning system, the ink compositions of Examples and Comparative Examples were filled and printed at 1.80 ^m2 , left at room temperature of 25 ° C. for 1 week, and then evaluated. (Indicated as "cleaning recoverability" in the table).
Evaluation A: Nozzle clogging is cleared within 5 times of normal cleaning.
Evaluation B: Nozzle clogging is not cleared even after 5 times of normal cleaning.

(7) Blocking resistance test The printer is filled with the ink compositions of Examples and Comparative Examples of oil-based inkjet recording ink, and a solid portion is printed on the recording medium in a high-quality printing mode. Was left for 24 hours after winding, and then unfolded to evaluate the set-off to the back surface and the surface of the printed matter that overlapped with the surface of the printed matter of the film (indicated as "blocking resistance" in the table).
Evaluation A: No set-off to the back surface is observed after winding, or there is little effect on the printed matter surface and there is virtually no effect.
Evaluation B: After winding, a large amount of set-off to the back surface is observed, and the surface of the printed matter is greatly roughened.

(8) Drying property test Using the ink compositions of Examples and Comparative Examples, the solid part was printed in a high quality printing mode (1440x720dpi), and the time until drying at 40 ° C. was measured (). In the table, it is written as "dryness").
Evaluation A: Dry in less than 10 minutes.
Evaluation B: Dry in 10 minutes or more.

From Tables 1 to 3, the ink composition for inkjet recording of the present invention has any of odor resistance test, printer member aptitude test, ejection stability test, intermittent ejection property test, cleaning recovery test, blocking resistance test, and drying property test. It can be seen that the ink composition is excellent in the above, and can simultaneously satisfy the above-mentioned requirements required for the recent inkjet recording method.

Claims (9)

An ink composition for inkjet recording.
It contains at least a coloring material, a resin, and a solvent represented by the following general formula (1).
An ink composition in which the content of impurities derived from the solvent is less than 1.0% by mass in the total amount of the solvent. However, the solvent excludes those containing diethylene glycol monobutyl ether or diethylene glycol dimethyl ether.
R _1- (OR ₂ ) _n -OR ₃ (1)
n: 1 or more and 4 or less integers,
R ₁ : May be branched with 1 or more carbon atoms and 8 or less Alkyl group R ₂ : May be branched with 1 or more carbon atoms and 4 or less alkylene group R ₃ : Hydrogen or branched with 1 or more carbon atoms and 4 or less carbon atoms Good alkyl group The ink composition according to claim 1, wherein the content of impurities derived from the solvent is 0.5% by mass or more and less than 1.0% by mass in the total amount of the solvent. The ink composition according to claim 1 or 2, wherein the impurities derived from the solvent are at least one selected from the group consisting of a multimer of the solvent, a side reaction product of the solvent, and a decomposition product of the solvent. The ink composition according to any one of claims 1 to 3, wherein the content of the impurities having a boiling point of more than 300 ° C. is less than 1.0% by mass in the total amount of the solvent. The ink composition according to any one of claims 1 to 4, wherein the content of the impurities having a boiling point of less than 150 ° C. is less than 1.0% by mass in the total amount of the solvent. A water-based inkjet recording ink composition containing water.
The ink composition according to any one of claims 1 to 5. An oil-based inkjet recording ink composition that does not contain water .
The ink composition according to any one of claims 1 to 5. An inkjet recording method for ejecting the ink composition according to any one of claims 1 to 7 onto the surface of a recording medium by an inkjet method. A method for producing a printed matter, which comprises a step of ejecting the ink composition according to any one of claims 1 to 7 onto the surface of a recording medium by an inkjet method.