JP2019199510A - Nonaqueous inkjet ink composition - Google Patents

Abstract

To provide a nonaqueous inkjet ink composition having excellent printing performance, capable of providing a high picture quality printed article regardless of high resistance and printing rate, and mainly suitable for printing onto a non-penetrable substrate.SOLUTION: There is provided a nonaqueous inkjet ink composition containing at least a coloring agent, an organic solvent (A), a binder resin, and an additive for surface control (B), in which (A) contains one or more kind of alkylene glycol monoalkyl ether solvent (a), total content of the (a) is 35 mass% to 80 mass% in the total amount of (A), the (B) contains an additive reducing surface tension at 25°C when 0.5 mass% of an additive for surface control to 3-methoxybutanol to 6.0 mN/m or more compared to no-addition 3-methoxybutanol.SELECTED DRAWING: None

Description

  The present invention relates to a non-aqueous ink-jet ink composition suitable for printing mainly on a non-permeable substrate, having excellent printing performance and capable of obtaining a printed material with high durability and high image quality.

  The ink jet recording method is a recording method in which characters and images are obtained by ejecting ink droplets directly from a very fine nozzle onto a recording member and attaching them. According to this method, there is an advantage that not only the noise of the apparatus to be used is small and the operability is good, but also colorization is easy and plain paper can be used as a recording member. It is widely used as an output machine in offices and homes.

  On the other hand, in industrial applications, it is used as an output device for digital printing due to improvements in inkjet technology, and non-aqueous (solvent type, UV type) inkjet inks can be printed on plastic substrates such as PVC and PET. Printing presses are actually marketed and used in various applications including outdoor advertising.

  In solvent-type non-aqueous ink jet inks, printing on a vinyl chloride base material is the mainstream, and conventionally, organic solvents such as cyclohexanone and ethylene glycol monobutyl ether acetate have been used (Patent Documents 1 and 2). In recent years, printing on various base materials has been demanded for expanding applications, and attention has been paid to the compatibility with non-penetrating flat bed base materials (Patent Document 3). As an example of ink that can be printed on a non-penetrable substrate, Patent Document 3 uses a polysiloxane additive, and uses a lactic acid ester solvent and a glycol monoester solvent in combination to improve the wetting and spreading properties of the ink composition. Improves the unevenness of the low printing area. On the other hand, producing high-quality prints that are not related to the printing rate may cause deterioration of the mottling where ink droplets adjoin each other in the high printing area due to excessive wetting and spreading, and the ink density may become non-uniform. It was difficult.

JP 2006-06991 A JP 2005-200469 A JP 2012-201838 A

  The present invention is a non-aqueous inkjet ink composition mainly suitable for printing on a non-permeable substrate, which has excellent printing performance and can obtain a high-quality printed material regardless of the printing rate. It is an issue to provide.

  As a result of intensive studies to solve the above-mentioned problems, the present inventors have found that the above-described problems can be solved by the following embodiment, and have completed the present invention.

That is, the present invention is a non-aqueous inkjet ink composition containing at least a colorant, an organic solvent (A), a binder resin, and a surface conditioning additive (B),
The organic solvent (A) contains one or more alkylene glycol monoalkyl ether solvents (a),
The total content of the alkylene glycol monoalkyl ether solvent (a) is 35% by mass or more and 80% by mass or less in the total amount of the organic solvent (A),
The surface preparation additive (B) has a surface tension at 25 ° C. of 6.0 mN when 0.5% by mass of the surface preparation additive is added to 3-methoxybutanol, compared to non-added 3-methoxybutanol. The present invention relates to a non-aqueous ink-jet ink composition characterized by containing an additive that decreases by at least / m.

  Further, in the present invention, the alkylene glycol monoalkyl ether solvent (a) is an alkylene glycol monoalkyl ether solvent (a ′) having a boiling point at 1 atm of 165 ° C. or less. a) It is related with the said non-aqueous inkjet ink composition characterized by containing 50 mass% or more in whole quantity.

Furthermore, in the present invention, the surface preparation additive (B) is a siloxane-modified acrylic resin,
The siloxane-modified acrylic resin is a graft copolymer of an acrylic resin and a siloxane compound, and relates to the non-aqueous inkjet ink composition.

  Furthermore, in the present invention, when the organic solvent (A) is allowed to stand for 200 minutes in an environment of 1 atm and 50 ° C., only the organic solvent (A) has a mass reduction rate of 50% by mass or more before and after standing. The present invention relates to the above non-aqueous inkjet ink composition.

  The present invention further relates to the above non-aqueous inkjet ink composition, wherein the organic solvent (A) further contains an alkylene glycol dialkyl ether solvent and / or an alkylene glycol monoalkyl ether monoacetate solvent.

  Furthermore, the present invention relates to the above non-aqueous ink-jet ink composition, wherein the alkylene glycol monoalkyl ether solvent (a) contains 3-methoxybutanol.

  Furthermore, the present invention relates to the above non-aqueous inkjet ink composition, which is for printing on a non-permeable substrate.

  Furthermore, this invention relates to the printed matter characterized by printing the said non-aqueous inkjet ink composition on the base material.

  According to the present invention, a non-aqueous ink-jet ink composition mainly suitable for printing on a non-permeable substrate, which has excellent printing performance and is capable of obtaining a printed material with high durability and high image quality regardless of the printing rate. It became possible to provide.

  Hereinafter, the present invention will be described in detail. In addition, embodiment described below demonstrates an example of this invention. The present invention is not limited to the following embodiments, and includes modifications that are implemented without departing from the scope of the present invention.

  In the present invention, in a non-aqueous ink-jet ink composition containing at least a colorant, an organic solvent (A), a binder resin, and a surface conditioning additive (B), an alkylene glycol monoester is used as the organic solvent (A). It contains at least one alkyl ether solvent (a), and the surface tension at 25 ° C. when added in an amount of 0.5% by mass to 3-methoxybutanol as the surface conditioning additive (B) By containing what is reduced by 6.0 mN / m or more as compared with methoxybutanol, it has high storage stability, exhibits excellent printing performance, and makes it possible to obtain a printed material with high durability and high image quality. The main components of the present invention are described below.

[Organic solvent (A)]
In the present invention, the organic solvent (A) contains at least one alkylene glycol monoalkyl ether solvent (a) represented by the following general formula 1, thereby improving the drying speed at the time of printing and further stabilizing the continuous printing. This makes it possible to exhibit excellent printing performance from the viewpoints of performance and decapability.

R1- (O-R2) _n- OH [General formula 1]

(R1 is an alkyl group having 1 to 6 carbon atoms, which may be linear or branched, and preferably has 1 or 2 carbon atoms.
R2 is an alkylene group having 2 to 6 carbon atoms, which may be linear or branched, more preferably 2 to 5 carbon atoms, and further preferably 3 or 4 carbon atoms. preferable.
n represents an integer of 1 to 4, and is more preferably 1 or 2. )

  As the alkylene glycol monoalkyl ether solvent (a) represented by the general formula 1, ethylene glycol monomethyl ether, ethylene glycol monobutyl ether, ethylene glycol monoisopropyl ether, ethylene glycol monohexyl ether, ethylene glycol mono-2-ethylhexyl ether , Propylene glycol monomethyl ether (1-methoxy-2-propanol), propylene glycol monobutyl ether, propylene glycol mono-n-propyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, diethylene glycol monoisopropyl ether, diethylene glycol monohexyl Ether, die Lenglycol mono-2-ethylhexyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol mono-n-propyl ether, dipropylene glycol monobutyl ether, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether , Triethylene glycol monobutyl ether, tripropylene glycol monomethyl ether, tripropylene glycol monobutyl ether, 3-methoxy-3-methylbutanol, 3-methoxybutanol, and the like. Among these, one kind or a combination of two or more kinds is used. it can. Among these, 1-methoxy-2-propanol, 3-methoxybutanol, 3-methoxy-3-methyl-1-butanol, and dipropylene glycol monomethyl ether are included from the viewpoint of continuous printing stability, odor, and drying. Among these, 3-methoxybutanol is particularly preferable from the viewpoint of solubility of the binder resin.

The total content of the alkylene glycol monoalkyl ether solvent (a) is preferably 35 to 80% by mass, and preferably 40 to 70% by mass in the total amount of the organic solvent (A) from the viewpoint of continuous printing stability and ink drying properties. More preferred.
Further, from the viewpoint of the drying property of the ink, the alkylene glycol monoalkyl ether solvent (a ′) having a boiling point of 165 ° C. or less at 1 atm is contained in an amount of 50% by mass or more in the total amount of the alkylene glycol monoalkyl ether solvent (a). It is more preferable.
The alkylene glycol monoalkyl ether solvent (a ′) having a boiling point of 165 ° C. or less at 1 atm is preferably 1-methoxy-2-propanol (boiling point 121 ° C.) or 3-methoxybutanol (boiling point 158 ° C.). From the viewpoint of solubility, 3-methoxybutanol is more preferable.

  Moreover, when only the organic solvent (A) is allowed to stand for 200 minutes in an environment of 1 atm and 50 ° C., the organic solvent (A) preferably has a mass decrease rate of 50% by mass or more before and after standing. When the mass reduction rate is 50% by mass or more, the drying property at the time of printing becomes good, and high image quality can be realized regardless of the printing rate.

  Further, when the organic solvent (A) contains an alkylene glycol dialkyl ether solvent represented by the general formula 2 and / or an alkylene glycol monoalkyl ether monoacetate solvent represented by the general formula 3, In addition, the surface tension during drying can be controlled to achieve high image quality regardless of the printing rate and substrate permeability.

R3- (O-R4) _m- OR5 [General formula 2]

(R3 and R5 are each independently an alkyl group having 1 to 4 carbon atoms, which may be linear or branched, and preferably has 1 or 2 carbon atoms.
R4 is an alkylene group having 2 to 4 carbon atoms, may be linear or branched, and more preferably has 2 or 3 carbon atoms.
m represents an integer of 1 to 4, and is more preferably 1 or 2. )

Examples of the alkylene glycol dialkyl ether solvent represented by the general formula 2 include ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol dibutyl ether, diethylene glycol methyl ethyl ether, diethylene glycol methyl butyl ether, triethylene glycol dimethyl ether, and triethylene glycol. Examples include diethyl ether, triethylene glycol methyl butyl ether, tetraethylene glycol dimethyl ether, dipropylene glycol dimethyl ether, dipropylene glycol diethyl ether, and tripropylene glycol dimethyl ether.
Of these, one or two or more can be used in combination. Among these, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol methyl ethyl ether, and dipropylene glycol dimethyl ether are preferably included from the viewpoint of storage stability and drying properties of the ink.

R6-CO- (O-R7) _1- OR8 [General formula 3]

(R6 is an alkyl group having 1 to 6 carbon atoms, which may be linear or branched, and preferably has 1 or 2 carbon atoms.
R8 is an alkyl group having 1 to 6 carbon atoms, may be linear or branched, and preferably has 1 to 4 carbon atoms.
R7 is an alkylene group having 2 to 6 carbon atoms, which may be linear or branched, and preferably has 2 to 4 carbon atoms.
l represents an integer of 1 to 6, preferably 1 to 4, and more preferably 1 or 2.

Examples of the alkylene glycol monoalkyl ether monoacetate solvent represented by the general formula 3 include (poly) ethylene glycol monoalkyl ether acetate, (poly) prolene glycol monoalkyl ether acetate, and (poly) butylene glycol monoalkyl ether. Examples include acetate. Specifically, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl Ether acetate, propylene glycol monobutyl ether acetate, dipropylene glycol monomethyl ether acetate, dipropylene glycol monoethyl ether acetate, dipropylene glycol monobutyl ether acetate, 3-methoxybutyl acetate, 3-methyl-3-methoxy Chill acetate, propylene glycol monomethyl ether propionate.
Of these, one or two or more can be used in combination. Among them, it contains ethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether acetate, dipropylene glycol monomethyl ether acetate, 3-methoxybutyl acetate. It is particularly preferable from the viewpoint.

In the present invention, other solvents can be used in combination for the purpose of adjusting the viscosity and dischargeability of the ink. Examples of other solvents include lactic acid esters, alkoxyalkylamides, alkanediols, cyclic ethers, heterocyclic solvents, and hydrocarbon solvents.
Specifically, methyl lactate, ethyl lactate, propyl lactate, butyl lactate, N, N-dimethyl-β-butoxypropionamide, N, N-dibutyl-β-butoxypropionamide, 3-methyl-2-oxazolidinone, 2 -Pyrrolidone (γ-butyrolactam), 1-methyl-2-pyrrolidone, ε-caprolactam, γ-butyrolactone, γ-valerolactone, ε-caprolactone, propylene carbonate and the like. From the viewpoint of penetrability of the ink into the substrate, 3-methyl-2-oxazolidinone, 2-pyrrolidone (γ-butyrolactam), and ε-caprolactone are more preferable. From the viewpoint of ink storage stability, 3-methyl-2-oxazolidinone (boiling point 266 ° C.) is preferred.

[Surface preparation additive (B)]
The alkylene glycol monoalkyl ether solvent (a) has a relatively higher surface tension than the solvent generally used in non-aqueous ink jet ink compositions, and it is difficult to obtain high image quality. In the present invention, as the surface conditioning additive (B), the surface tension at 25 ° C. when adding 0.5 mass% of the surface conditioning additive to 3-methoxybutanol is higher than that of 3-methoxybutanol not added. By containing an additive that has a feature of lowering 6.0 mN / m or more, the surface tension of the alkylene glycol monoalkyl ether solvent is reduced, and high image quality is achieved regardless of the printing rate and substrate permeability. I was able to.

  Examples of the surface conditioning additive (B) include silicon-based, silicon acrylic-based, acrylic-based, fluorine-based, and acetylene glycol-based surfactants. As described above, the surface tension reducing ability with respect to 3-methoxybutanol is demonstrated. Any of those containing 6.0 mN / m or more can be used. The surfactant having a surface tension reducing ability of 6.0 mN / m or more is preferably contained in an amount of 50% by mass or more based on the total amount of the surface preparation additive (B).

Among them, it is particularly preferable to contain a silicon-based or silicon acrylic-based surfactant from the viewpoint of high surface tension reducing ability with respect to the alkylene glycol monoalkyl ether solvent (a).
As the silicon-based surface conditioning additive, for example, a modified polysiloxane compound in which an organic group is introduced into a part of the methyl group of polydimethylsiloxane is preferable. Examples of modification include polyether modification, methylstyrene modification, alcohol modification, alkyl modification, aralkyl modification, fatty acid ester modification, epoxy modification, amine modification, amino modification, mercapto modification, etc. is not. These modification methods can be used in combination.
Of these, polyether-modified polysiloxane compounds and aralkyl-modified polysiloxane compounds are preferred in terms of abrasion resistance and the like.
The silicon acrylic surface conditioning additive is preferably a siloxane-modified acrylic resin that is a graft copolymer of an acrylic resin and a siloxane compound, for example.

Examples of the polyether-modified polysiloxane compound include, for example, KF-353A, KF-354L, KF6017, X-22-6551, AW-3 manufactured by Shin-Etsu Chemical Co., Ltd., SAG001 manufactured by Nissin Chemical Industry Co., Ltd. SAG002, SAG003, SAG005, SAG503A, SAG008, SAG010, Toray Dow Corning Co., Ltd. BYK-300, 302, 3 manufactured by Big Chemie Japan 6,307,333,330,377, Evonik Degussa Corporation of TEGO Glide 100,110,130,406,410,415,420,432,435,440,450, and the like.
Examples of the aralkyl-modified polysiloxane compound include BYK-322 and 323 manufactured by BYK Japan Japan, KF-410 manufactured by Shin-Etsu Chemical Co., Ltd., SM 7001EX and SM manufactured by Toray Dow Corning. 7002EX etc. are mentioned.
Examples of silicon acrylic surface conditioning additives include Shin-Etsu Chemical Co., Ltd. KP541, KP543, KP545, BYK-3550, BYK-3 Japan, BYK-SILCLEAN3700, LHP-810, Enomoto Kasei Co., Ltd. Etc.

  The total content of the surface conditioning additive (B) is preferably 0.001 to 2% by mass, more preferably 0.001 to 1% by mass, based on the total amount of ink, and 0.03. More preferably, it is -0.5 mass%, and it is most preferable that it is 0.1-0.3 mass%.

[Colorant]
As the colorant used in the non-aqueous ink jet ink composition of the present invention, inorganic pigments, organic pigments, dyes and the like can be used. These colorants may be colorants generally used for inks for printing applications and paint applications, and an appropriate colorant can be selected according to the required applications such as color development and light resistance. . These colorants may be used alone or in combination of two or more.

  When a pigment is used as the colorant, an achromatic pigment such as carbon black, titanium oxide, calcium carbonate, or a chromatic organic pigment can be used.

  Examples of organic pigments preferably used in the present invention are color index (CI) numbers. I. Pigment Yellow 12, 13, 14, 15, 16, 17, 20, 24, 55, 74, 83, 86, 87, 93, 109, 110, 117, 120, 125, 124, 128, 129, 137, 138, 139, 147, 148, 150, 151, 153, 154, 155, 166, 168, 170, 171, 172, 174, 176, 180, 185, 188, C.I. I. Pigment orange 16, 36, 43, 51, 55, 59, 61, 64, C.I. I. Pigment Red 9, 48, 49, 52, 53, 57, 97, 122, 123, 146, 149, 150, 168, 177, 180, 185, 192, 202, 206, 207, 209, 215, 216, 217, 220, 223, 224, 226, 227, 228, 238, 240, 245, 269, 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, 22, 60, 64, C.I. I. Pigment green 7, 36, C.I. I. Pigment brown 23, 25, 26, C.I. I. Pigment black 1, 6, 7 etc. are mentioned.

  The content of these pigments in the ink is preferably 1 to 20% by mass, more preferably 1 to 8% by mass, and most preferably 2 to 5% by mass from the viewpoints of coloring power, storage stability, and inkjet viscosity suitability. . When light color ink is used to reduce image graininess, the pigment content is preferably 1/10 to 1/2 that of dark color ink, more preferably 1/5 to 1/3. preferable.

  The average particle diameter of the organic pigment is preferably a fine pigment having a D50 of 50 to 350 nm. When the average particle diameter of the pigment is 50 nm or more, light resistance and coloring power can be obtained, and when it is 350 nm or less, the ink stability and the dischargeability are good. The average particle diameter of the pigment is the median diameter (D50) when the inkjet ink is diluted 200 to 1000 times with ethyl acetate and measured with a MICROTRAC UPA150 manufactured by Nikkiso Co., Ltd.

[Pigment dispersant]
When constituting an ink containing a pigment as an embodiment of the present invention, it is preferable to use a pigment dispersant in order to improve the dispersibility of the pigment and the storage stability of the ink. Conventionally known compounds can be used as the pigment dispersant, but it is preferable to use a resin-type dispersant having a basic functional group from the viewpoint of ejection characteristics and ink storage stability.

  Examples of the pigment dispersant include Lubrizol's Solsperse 32000, 76400, 76500, J200, and J180, etc .; Big Chemie's Disperbyk-161, 162, 163, 164, 165, 166, 167, and 168; Ajinomoto Fine Techno Co., Ltd. Ajisper PB821, PB822 etc. are mentioned.

  The weight average molecular weight (hereinafter referred to as Mw) of the pigment dispersant is preferably 5,000 to 50,000, and more preferably 10,000 to 45,000. If Mw is 5,000 or more, the stability of the pigment dispersion is improved because the stability of the pigment dispersant itself in the organic solvent used in the ink is good. When it is 50,000 or less, the compatibility with the binder resin becomes good, the whitening phenomenon of the ink coating film is suppressed, and the color developability becomes good.

Further, in the pigment dispersant, the ratio of the weight average molecular weight (Mw) to the number average molecular weight (Mn), Mw / Mn is preferably 2 or less, and more preferably 1.8 or less.
When Mw / Mn is 2 or less, it is possible to obtain a pigment dispersion with little variation in the dispersed particle diameter of the pigment, and it is possible to achieve both low viscosity and storage stability of the pigment dispersion.

  The acid value (mgKOH / g) of the pigment dispersant is preferably from 5 to 20, and more preferably from 5 to 15. The amine value (mgKOH / g) is preferably 5 to 50, more preferably 20 to 50, and still more preferably 25 to 40. When the acid value and amine value of the pigment dispersant are within the above ranges, in the pigment dispersion step, the time until the viscosity of the pigment dispersion becomes low enough to be suitable for an inkjet ink is shortened. It is preferable because storage stability is improved.

Here, “Mw” can be determined as a molecular weight in terms of polystyrene by general gel permeation chromatography (hereinafter, GPC). For example, using TSKgel column (manufactured by Tosoh Corporation), GPC (manufactured by Tosoh Corporation, HLC-8320GPC) equipped with an RI detector can be represented by polystyrene equivalent molecular weight when DMF is used as a developing solvent.
The “acid value” represents an acid value per 1 g of the solid content of the dispersant, and can be determined by potentiometric titration according to JIS K 0070. The “amine value” represents an amine value per 1 g of the solid content of the dispersant, and is a value converted to an equivalent of potassium hydroxide after being determined by potentiometric titration using a 0.1N hydrochloric acid aqueous solution.

  The content of the pigment dispersant is preferably 0.1 to 10% by mass and more preferably 0.1 to 5% by mass in the total amount of the ink. When the pigment dispersant is contained in an amount of 0.1% by mass or more, the storage stability of the ink is improved, and when it is 10% by mass or less, the viscosity of the ink is in a suitable range, and good dischargeability is obtained.

  A pigment derivative can also be used in the ink of the present invention. The pigment derivative is used for the purpose of further improving the adsorptivity with the pigment dispersant and improving the storage stability. As the pigment derivative, a compound having an acidic group such as a sulfonic acid group or a carboxyl group in the organic pigment residue is preferably used.

  The content of the pigment derivative is preferably from 0.1 to 20 mass%, more preferably from 1 to 15 mass%, based on the pigment. When the pigment derivative is 0.1% by mass or more, stability and color developability are improved, and when it is 20% by mass or less, the viscosity of the ink is in a suitable range, and the storage stability is improved.

[Binder resin]
As the binder resin used in the present invention, those exhibiting functions such as scratch resistance, alcohol resistance, stretchability, glossiness and substrate versatility of the ink coating film can be used. For example, acrylic resin, styrene-acrylic resin, styrene-maleic acid resin, vinyl chloride resin, vinyl chloride resin, rosin modified resin, ethylene vinyl acetate resin, terpene resin, phenol resin, urethane resin Commonly used resins such as melamine resin, epoxy resin, cellulose resin, butyral resin, polyvinyl alcohol, polyester resin and polyamide resin can be used. These binder resins may be used alone or in combination of two types.

As specific examples of the binder resin, BR-50, BR-52, MB-2539, BR-60, BR-64, BR-73 are acrylic resins of the Dynal (registered trademark) BR series manufactured by Mitsubishi Chemical Corporation. , BR-75, MB-2389, BR-80, BR-82, BR-83, BR-84, BR-85, BR-87, BR-88, BR-90, BR-95, BR-96, BR -100, BR-101, BR-102, BR-105, BR-106, BR-107, BR-108, BR-110, BR-113, MB-2660, MB-2952, MB-3012, MB-3015 , MB-7033, BR-115, MB-2478, BR-116, BR-117, BR-118, BR-122, ER-502;
As an acrylic resin of Paraloid (registered trademark) series manufactured by Wilber Ellis, A-11, A-12, A-14, A-21, B-38, B-60, B-64, B-66, B-72, B-82, B-44, B-48N, B-67, B-99N, DM-55;
As JONCRYL (registered trademark) series styrene-acrylic resins manufactured by BASF, JONCRYL 67, 678, 586, 611, 680, 682, 683, 690, 819, JDX-C3000, JDXC3080;
As solvine (registered trademark) series vinyl chloride resin of Nissin Chemical Industry, sorbine CL, CNL, C5R, TA3, TA5R (suspension polymerization product), VINOLL (registered trademark) series of vinegar manufactured by Wacker As vinyl resins, VINNOL E15 / 45, E15 / 45M, E15 / 40M, E15 / 48A (emulsion polymerization product), H15 / 50, H15 / 42, H14 / 36, E18 / 38, H40 / 43, H11 / 59, H15 / 45M (suspension polymerization method product);
As rosin ester resin made by Arakawa Chemical Co., Ltd., Superester 75, Ester Gum HP, Malkid 33;
As a terpene phenol resin made by Yasuhara Chemical Co., Ltd., YS Polystar T80;
Examples of the styrene-maleic acid resin manufactured by Sartomer include SMA2625P.

  Among the binder resins, a vinyl acetate resin and an acrylic resin are preferable from the viewpoints of alcohol resistance, abrasion resistance, glossiness and the like of the ink coating film. These may be used alone or in combination of two or more.

Vinyl chloride-based resin is a copolymer of vinyl chloride and vinyl acetate. Examples of this polymerization method include polymerization methods such as solution polymerization, suspension polymerization, and emulsion polymerization. In the present invention, it is preferable to use a vinyl chloride resin produced by solution polymerization or emulsion polymerization.
The mass ratio of vinyl chloride and vinyl acetate is preferably 95: 5 to 70:30, more preferably 90:10 to 80:20.

  The acrylic resin is a polymer containing an acrylic acid ester or a methacrylic acid ester, and in the present invention, a polymer containing a methacrylic acid ester is preferable. As the methacrylic acid ester, methyl methacrylate (MMA) and butyl methacrylate ( A copolymer of BMA) is preferably used. The mass ratio of MMA to BMA is preferably 100: 0 to 60:40, and more preferably 90:10 to 70:30.

  The binder resin preferably has a weight average molecular weight (Mw) of 3,000 to 70,000, more preferably 5,000 to 60,000, and still more preferably 10,000 to 60,000. If the Mw is 3,000 or more, the ink coating film is sufficiently resistant, and if it is 70,000 or less, it is preferable because no load is applied to the discharge from the minute ink jet printer head. In the said range, it is excellent in compatibility with a dispersing agent and a whitening phenomenon is suppressed.

  The weight average molecular weight (Mw) of the vinyl chloride-based resin is preferably 3,000 to 70,000, more preferably 5,000 to 60,000, and still more preferably 30,000 to 60,000.

  The weight average molecular weight (Mw) of the acrylic resin is preferably 3,000 to 100,000, more preferably 5,000 to 70,000, and still more preferably 10,000 to 45,000.

  0-100 are preferable, as for the acid value (mgKOH / g) of acrylic resin, 0-80 are more preferable, and 0-20 are more preferable.

  0-150 degreeC is preferable, as for the glass transition temperature of acrylic resin, 20-100 degreeC is more preferable, and 40-80 degreeC is further more preferable.

  It is preferable that 1-20 mass% of binder resin is contained in the ink whole quantity, 2-10 mass% is more preferable, and 3-8 mass% is further more preferable. When the total amount of the ink is 1% by mass or more, the adhesion of the ink to the surface of the recording medium is improved and the resistance of the ink coating film is improved. When the content is 20% by mass or less, the ink viscosity is low, which is preferable because ink jet discharge suitability is improved.

  The vinyl chloride-based resin is preferably contained in an amount of 0.1 to 10% by mass, more preferably 0.3 to 7% by mass, based on the total amount of the ink.

  The acrylic resin is preferably contained in the total amount of the ink in an amount of 1 to 20% by mass, and more preferably 1 to 10% by mass.

[recoding media]
The recording medium used in the present invention is not particularly limited, but plastic substrates such as soft vinyl chloride, hard vinyl chloride, polystyrene, polystyrene foam, PMMA, polypropylene, polyethylene, polyester, PET, polycarbonate, and mixtures or modifications thereof. Products, high-quality paper, art paper, coated paper, cast coated paper, paper base materials such as cardboard, and metal base materials such as glass, stainless steel, and aluminum. Of these, soft vinyl chloride sheets, hard vinyl chloride sheets, and corrugated cardboard are preferably used from the viewpoint of price and processability, and glass, stainless steel, and aluminum, which are non-permeable substrates, are particularly preferable from the viewpoint of printing with high image quality. Preferably used.

[Inkjet ink production method]
The ink of the present invention can be produced by a known method, and specifically, it is carried out as follows. First, after mixing a single or mixed organic solvent, pigment, binder resin, dispersant, etc. when blended, the pigment is dispersed by a paint shaker, sand mill, roll mill, medialess disperser, etc. The body is prepared, and the obtained pigment dispersion is obtained by adding the remainder of the organic solvent, the remainder of the binder resin, and other additives (for example, a surface conditioner) so as to have desired ink characteristics.

[Physical properties of inkjet ink]
In the ink of the present invention, the surface tension at 25 ° C. is preferably 20 to 50 mN / m from the viewpoint of the balance between the ejectability from the inkjet print head and the reliability of dot formation after landing, and preferably 21 to 40 mN / m. m is more preferable, and 22 to 30 mN / m is further more preferable. From the same viewpoint, the viscosity at 25 ° C. is preferably 2 to 20 mPa · s, more preferably 3 to 15 mPa · s, and further preferably 5 to 12 mPa · s.
The surface tension can be measured by confirming the surface tension when the platinum plate is wetted with ink in an environment of 25 ° C. using an automatic surface tension meter CBVP-Z manufactured by Kyowa Interface Science Co., Ltd. it can. The viscosity can be measured by reading the viscosity at 50 rpm in an environment of 25 ° C. using a TVE25L viscometer manufactured by Toki Sangyo Co., Ltd.

  EXAMPLES Hereinafter, although an Example and a comparative example demonstrate this invention concretely, this invention is not specifically limited to an Example. In the following description, “parts” and “%” represent “parts by mass” and “% by mass”, respectively, unless otherwise specified.

(Evaluation of surface tension reduction ability)
Various additives were added to 3-methoxybutanol so as to have a solid content of 0.5% by mass, and after mixing well, the surface tension was measured. The measurement was performed by a plate method using a platinum plate under an environment of 25 ° C. using an automatic surface tension meter CBVP-Z manufactured by Kyowa Interface Science Co., Ltd. Similarly, diethylene glycol diethyl ether, 3-methoxybutyl acetate, and ethylene glycol monobutyl ether acetate were also measured. Table 1 shows the measurement results of the surface tension when various additives were added and the difference (Δ) from the surface tension of the solvent to which no additives were added.

(Production example of pigment dispersion I)
20 parts of Pigment Blue 15: 4 as a pigment, 10 parts of Solsperse 32000 as a pigment dispersant and 70 parts of diethylene glycol diethyl ether were mixed, predispersed with a disper, and filled with 1800 g of zirconia beads having a diameter of 0.5 mm. This dispersion was carried out for 2 hours using a 6 L dyno mill to obtain a pigment dispersion I (Cyan). Pigment Blue 15: 4 was changed to Pigment Red 122, and Pigment Dispersion Liquid I (Magenta) was obtained in the same manner. Pigment Blue 15: 4 was changed to Pigment Yellow 150, and Pigment Dispersion I (Yellow) was obtained in the same manner. Pigment Blue 15: 4 was changed to Pigment Black 7, and Pigment Dispersion Liquid I (Black) was obtained in the same manner.

(Production Example of Pigment Dispersion Liquid II)
20 parts of Pigment Blue 15: 4 as a pigment, 10 parts of Solsperse 32000 as a pigment dispersant, and 70 parts of ethylene glycol monobutyl ether acetate were mixed, predispersed with a disper, and then filled with 1800 g of zirconia beads having a diameter of 0.5 mm. This dispersion was carried out for 2 hours using a 0.6 L dyno mill to obtain Pigment Dispersion Liquid II (Cyan). Pigment Blue 15: 4 was changed to Pigment Red 122, and Pigment Dispersion Liquid II (Magenta) was obtained in the same manner. Pigment Blue 15: 4 was changed to Pigment Yellow 150, and Pigment Dispersion Liquid II (Yellow) was obtained in the same manner. Pigment Blue 15: 4 was changed to Pigment Black 7, and Pigment Dispersion Liquid II (Black) was obtained in the same manner.

(Production Example of Pigment Dispersion Liquid III)
20 parts of Pigment Blue 15: 4 as a pigment, 10 parts of Solsperse 32000 as a pigment dispersant, and 70 parts of 3-methoxybutanol were mixed, predispersed with a disper, and filled with 1800 g of zirconia beads having a diameter of 0.5 mm. This dispersion was performed for 2 hours using a 0.6 L dyno mill to obtain Pigment Dispersion Liquid III (Cyan). Pigment Blue 15: 4 was changed to Pigment Red 122, and Pigment Dispersion Liquid III (Magenta) was obtained in the same manner. Pigment Blue 15: 4 was changed to Pigment Yellow 150, and Pigment Dispersion Liquid III (Yellow) was obtained in the same manner. Pigment Blue 15: 4 was changed to Pigment Black 7, and Pigment Dispersion Liquid III (Black) was obtained in the same manner.

Example 1
20 parts of pigment dispersion I (Cyan), 3.9 parts of Dynal BR-113 as a binder resin, 0.1 part of BYK-3550 as an additive for surface preparation (B), 50 parts of 3-methoxybutanol, 26 parts of 3-methoxybutyl acetate were sequentially added while stirring with a disper and stirred until it was sufficiently uniform. Thereafter, filtration with a membrane filter was performed to remove coarse particles that would cause clogging of the head, and the cyan ink for inkjet according to the present invention was prepared. Similarly, magenta ink, yellow ink, and black ink were prepared using Pigment Dispersion Liquid I (Magenta, Yellow, Black). The ink-jet ink thus prepared was filled into VJ-628 (an ink jet printer manufactured by Muto Kogyo Co., Ltd.) as one ink set, and printing evaluation was performed in a 25 ° C. environment using a polyvinyl chloride sheet as a printing medium.

(Example 2 to Example 22, Example 28, Comparative Example 1 to Comparative Example 7)
An ink set was prepared in the same manner as in Example 1, except that the organic solvent (A) and the surface preparation additive (B) in Example 1 were changed to the compositions in Tables 2 to 5.

(Example 23)
20 parts of Pigment Dispersion Liquid II (Cyan), 3.9 parts of Dynal BR-113 as binder resin, 0.1 part of BYK-3550 as additive for surface preparation (B), 50 parts of 3-methoxybutanol, 26 parts of 3-methoxybutyl acetate were sequentially added while stirring with a disper and stirred until it was sufficiently uniform. Thereafter, filtration with a membrane filter was performed to remove coarse particles that would cause clogging of the head, and the cyan ink for inkjet according to the present invention was prepared. Similarly, magenta ink, yellow ink, and black ink were prepared using Pigment Dispersion Liquid II (Magenta, Yellow, Black). The ink-jet ink thus prepared was filled into VJ-628 (an ink jet printer manufactured by Muto Kogyo Co., Ltd.) as one ink set, and printing evaluation was performed in a 25 ° C. environment using a polyvinyl chloride sheet as a printing medium.

(Examples 24 to 27, Example 29, Comparative Example 8)
An ink set was produced in the same manner as in Example 23, except that the organic solvent (A) and the surface preparation additive (B) in Example 23 were changed to the compositions in Tables 4 and 5.

(Example 30)
20 parts of pigment dispersion III (Cyan), 3.9 parts of Dynal BR-113 as binder resin, 0.1 part of BYK-3550 as additive (B) for surface preparation, 26 parts of 3-methoxybutanol, 10 parts of epsilon-caprolactone and 40 parts of L-ethyl lactate were sequentially added while stirring with a disper and stirred until it was sufficiently uniform. Thereafter, filtration with a membrane filter was performed to remove coarse particles that would cause clogging of the head, and the cyan ink for inkjet according to the present invention was prepared. Similarly, magenta ink, yellow ink, and black ink were prepared using Pigment Dispersion Liquid III (Magenta, Yellow, Black). The ink-jet ink thus prepared was filled into VJ-628 (an ink jet printer manufactured by Muto Kogyo Co., Ltd.) as one ink set, and printing evaluation was performed in a 25 ° C. environment using a polyvinyl chloride sheet as a printing medium.

(Example 31)
An ink set was produced in the same manner as in Example 30, except that the organic solvent (A) and the surface preparation additive (B) in Example 30 were changed to the compositions shown in Table 4.

  The performance of the inkjet inks obtained in the examples and comparative examples was evaluated by the following methods. In addition, the evaluation point was made into the evaluation point of the lowest evaluation ink among each color ink.

(Storage stability evaluation)
The viscosity of the prepared ink was measured using an E-type viscometer (TVE-20L manufactured by Toki Sangyo Co., Ltd.) at 25 ° C. and 50 rpm. This ink was stored in a thermostat at 70 ° C., and the viscosity change of the ink before and after aging was evaluated. The evaluation criteria are as follows, and 3 or more was considered good.
5: Viscosity change rate after storage for 10 weeks is less than ± 10% 4: Viscosity change rate after storage for 8 weeks is less than ± 10% 3: Viscosity change rate after storage for 6 weeks is less than ± 10% 2: Storage for 4 weeks Viscosity change rate after less than ± 10% 1: Viscosity change rate after storage for 4 weeks ± 10% or more

(Continuous printing stability evaluation)
A solid image (width 1 m × length 10 m) with a printing rate of 100% for each ink color was printed with the printer, and the degree of nozzle omission that occurred after printing was confirmed. The evaluation criteria are as follows, and 3 or more was considered good.
5: No missing nozzle 4: Nozzle missing 2% or less 3: Nozzle missing 5% or less 2: Nozzle missing 10% or less 1: Nozzle missing 10% or more

(Decapability evaluation)
The printer head was filled with evaluation ink, printed and confirmed that there was no nozzle omission at the beginning, then left for a certain period of time and printed again. At this time, it was confirmed whether or not nozzle missing occurred. The evaluation criteria are as follows, and 3 or more was considered good.
5: No nozzle missing even after standing for 1 week: No nozzle missing after 1 day: 3: No nozzle missing after 3 hours left No nozzle missing even after left for 1 hour: Nozzle missing after standing for 1 hour Do

(Rubbing resistance evaluation)
A solid image with a printing rate of 100% (each length: 15 cm × width: 3 cm) was printed for each ink color with the above printer, and the printed matter dried at room temperature for 24 hours was used as a Gakushoku type friction fastness tester (AB-301 manufactured by Tester Sangyo). ), The abrasion resistance was evaluated using a gold width No. 3 as a friction element. A test was performed by changing the load and the number of reciprocations, and the peeling of the printed surface was evaluated. The evaluation criteria are as follows, and 3 or more was considered good.
The print surface does not peel off at 5: 1 kg load and 50 reciprocations. 4: 500 g load, the print surface does not peel off at 100 reciprocations. 3: The 500 g load, the print surface does not peel off at 50 reciprocations. Does not peel 1: 200g load, print surface peels after 100 reciprocations

(Evaluation of granularity of low print area)
The above printer prints a uniform solid image (each 1.5cm x 1.5cm) with a low printing rate (10 to 40%) for each color of ink, and visually confirms the presence or absence of graininess in the low printing area after printing. Observed. Granularity is a phenomenon in which dots are fused and the background is conspicuous and the image quality looks rough. The lower the printing rate, the more noticeable the graininess. The evaluation criteria are as follows, and 3 or more was considered good.
5: No graininess at a printing rate of 10% 4: No graininess at a printing rate of 20% 3. No graininess at a printing rate of 30% 2: No graininess at a printing rate of 40% 1: Printing rate of 40% There is a feeling of grain

(Evaluation of uneven density in high print area)
The above printer prints a uniform solid image (each 1.5cm x 1.5cm) with a high printing rate (100 to 200%) for each ink color, and after printing, the ink density in the high printing area is uneven. The presence or absence of crystallization was observed. Ink density non-uniformity means low and high density parts from the edge part of the image to the central part when comparing the color density of each part of the printed image with the central part printed at a constant density. Is a phenomenon in which the concentration becomes constant as the central portion approaches. Density unevenness tends to occur as the printing rate increases. The evaluation criteria are as follows, and 3 or more was considered good.
The 100% printing rate is a 100% solid image for each single color, the 120% printing rate is 60% overlaid for each of two colors of cyan, magenta, and yellow, and the 160% printing rate is cyan, magenta, yellow. Of these, 80% overlapping images of two colors and a printing rate of 200% were evaluated for 100% overlapping images of two colors of cyan, magenta, and yellow.
5: No ink density unevenness at a printing rate of 200% 4: No ink density unevenness at a printing rate of 160% 3: No ink density unevenness at a printing rate of 120% 2: Printing rate of 100 % Ink density non-uniformity 1: Ink density non-uniformity at 100% printing rate

(Non-permeable substrate drawability evaluation)
The base material of the printer was changed from a polyvinyl chloride sheet to a glass plate, and a solid image was printed while changing the printing rate (100 to 200%). In a non-permeable substrate, the higher the printing rate, the slower the drying and the more likely bleeding occurs. It was judged that drawing was possible when there was no visible blur. The evaluation criteria are as follows, and 3 or more was considered good.
5: Printing is possible at a printing rate of 200% 4: Printing is possible at a printing rate of 160% 3: Printing is possible at a printing rate of 120% 2: Printing is possible at a printing rate of 100% 1: Printing is not possible at a printing rate of 100% Possible

In addition, the component used in Tables 1-5 is as follows.
-Resin ("Dianal BR-113" acrylic resin manufactured by Mitsubishi Chemical Corporation, weight average molecular weight 30,000, glass transition point 75 ° C, acid value 3.5)
-BYK-3550 (trade name, manufactured by Big Chemie Japan Co., Ltd., silicon-modified acrylic)
・ BYK-SILCLEAN3700 (trade name, manufactured by BYK Japan Japan, hydroxyl-containing silicon-modified acrylic)
・ LHP-810 (trade name, manufactured by Enomoto Kasei Co., Ltd., acrylic silicone polymer)
・ KP541 (trade name, manufactured by Shin-Etsu Chemical Co., Ltd., (Acrylates / Dimethicone) copolymer)
BYK-322 (trade name, manufactured by Big Chemie Japan, aralkyl-modified polymethylalkylsiloxane)
BYK-331 (trade name, manufactured by Big Chemie Japan Co., Ltd., polyether-modified polydimethylsiloxane)
BYK-333 (trade name, manufactured by Big Chemie Japan Co., Ltd., polyether-modified polydimethylsiloxane)
-BYK-361N (trade name, manufactured by Big Chemie Japan, Inc., acrylic copolymer)
MP (3-methoxypropanol, boiling point 121 ° C.)
MB (3-methoxybutanol, boiling point 158 ° C.)
MMB (3-methoxymethylbutanol, boiling point 174 ° C.)
DPM (dipropylene glycol monomethyl ether, boiling point 188 ° C.)
DPDM (dipropylene glycol dimethyl ether, boiling point 171 ° C.)
・ MEDG (diethylene glycol methyl ethyl ether, boiling point 176 ° C.)
・ DEDG (diethylene glycol diethyl ether, boiling point 189 ° C)
MBA (3-methoxybutyl acetate, boiling point 171 ° C.)
・ BGAc (ethylene glycol monobutyl ether acetate, boiling point 192 ° C.)
ECL (epsilon-caprolactone, boiling point 253 ° C)
DAA (diacetone alcohol, boiling point 166 ° C.)
・ Ethyl lactate (L-ethyl lactate, boiling point 154 ° C.)

  As shown in Tables 2 to 4, by containing 35% by mass or more and 80% by mass or less of the alkylene glycol monoalkyl ether solvent (a) in the total amount of the organic solvent (A), storage stability, continuous printing stability, Decapability can be satisfied at a high level. Furthermore, by adding the additive (B) for surface preparation that lowers the surface tension by 6.0 mN / m or more from the non-added 3-methoxybutanol by adding to 3-methoxybutanol in Table 1, low printing can be achieved. The graininess of the part and the density non-uniformity of the high printing part are less likely to appear, and the drawing on the non-permeable substrate can be performed at a high level. In addition, by including an alkylene glycol dialkyl ether solvent and / or an alkylene glycol monoalkyl ether monoacetate solvent, the scrub resistance is also highly evaluated. On the other hand, as shown in Table 5, in Comparative Examples 1 to 8, ink that satisfies the drawing on the non-permeable base material was not obtained, and the evaluation items were at low levels.

Claims (8)

A non-aqueous inkjet ink composition comprising at least a colorant, an organic solvent (A), a binder resin, and a surface conditioning additive (B),
The organic solvent (A) contains one or more alkylene glycol monoalkyl ether solvents (a),
The total content of the alkylene glycol monoalkyl ether solvent (a) is 35% by mass or more and 80% by mass or less in the total amount of the organic solvent (A),
The surface preparation additive (B) has a surface tension at 25 ° C. of 6.0 mN when 0.5% by mass of the surface preparation additive is added to 3-methoxybutanol, compared to non-added 3-methoxybutanol. A non-aqueous ink-jet ink composition comprising an additive that decreases by / m or more.   In the total amount of the alkylene glycol monoalkyl ether solvent (a), the alkylene glycol monoalkyl ether solvent (a) has a boiling point at 1 atm of 165 ° C. or less. The non-aqueous inkjet ink composition according to claim 1, which is contained in an amount of 50% by mass or more. The surface preparation additive (B) is a siloxane-modified acrylic resin,
The non-aqueous inkjet ink composition according to claim 1 or 2, wherein the siloxane-modified acrylic resin is a graft copolymer of an acrylic resin and a siloxane compound.   The organic solvent (A) is characterized in that when only the organic solvent (A) is allowed to stand for 200 minutes in an environment of 1 atm and 50 ° C., the mass reduction rate before and after standing is 50% by mass or more. Item 4. The non-aqueous inkjet ink composition according to any one of Items 1 to 3.   The non-aqueous inkjet ink composition according to any one of claims 1 to 4, wherein the organic solvent (A) further contains an alkylene glycol dialkyl ether solvent and / or an alkylene glycol monoalkyl ether monoacetate solvent. .   The non-aqueous inkjet ink composition according to any one of claims 1 to 5, wherein the alkylene glycol monoalkyl ether solvent (a) contains 3-methoxybutanol.   The non-aqueous inkjet ink composition according to claim 1, which is for printing on a non-permeable substrate. A printed matter, wherein the non-aqueous inkjet ink composition according to any one of claims 1 to 7 is printed on a substrate.