JP5077359B2 - Non-aqueous inkjet ink package and inkjet recording method - Google Patents

Description

  The present invention relates to a novel non-aqueous inkjet ink package and an inkjet recording method.

  In recent years, the inkjet recording method can be easily and inexpensively created images, and thus has been applied to various printing fields such as photographs, various printing, marking, and special printing such as color filters.

  As the ink-jet ink used in such an ink-jet recording method, water-based ink mainly containing water, non-volatile solvent which does not volatilize at room temperature, oil-based ink which does not substantially contain water, solvent which volatilizes at room temperature A non-aqueous ink that is substantially free of water, a hot melt ink that heats and melts solid ink at room temperature, an actinic ray curable ink that cures with actinic rays such as light after printing, and the like. There are inkjet inks, and they are properly used depending on the application.

  On the other hand, plastic recording media such as polyvinyl chloride and polyethylene are used as recording media for outdoor postings that require long-term weather resistance and printed materials that require adhesion to curved objects. Recording media made of soft polyvinyl chloride are used in a wide range of applications. There are many methods for printing on soft polyvinyl chloride, but there is an inkjet recording method as a method suitable for the production of a small variety of products because there is no need to prepare a plate and the time to finish is short.

  When performing inkjet recording on soft polyvinyl chloride, the inkjet ink used conventionally includes cyclohexanone, N-methylpyrrolidone, etc., which have a solubility in soft polyvinyl chloride, and glycol acetates as the main solvent. Non-aqueous ink is used (see Patent Documents 1 and 2). In these ink-jet inks, solvents such as cyclohexanone and N-methylpyrrolidone have high solubility in soft polyvinyl chloride, and the pigment in the ink-jet ink penetrates into soft polyvinyl chloride, so it has good scratch resistance and gloss. Is obtained.

  By the way, when trying to fill the above-mentioned non-aqueous inkjet ink into a plastic bottle which is excellent in inexpensive and economical advantages, light weight, high strength, heat resistance, cold resistance, chemical resistance, etc. The plastic bottle itself has a slight property of allowing moisture in the air to pass inside, and the problem is that the non-water-based inkjet ink packed in the bottle absorbs moisture and causes a problem. It was.

  For example, in a water-absorbing ink-jet ink, the dispersion of a pigment that is insoluble in water becomes unstable and the aggregate of the pigment precipitates, or the polymer compound added as a pigment dispersant or fixing resin is also in water. Since many of them are difficult to dissolve, there is a problem that the solubility becomes unstable and precipitation occurs. Further, even if precipitation does not occur, the viscosity of the ink is increased, the output from the inkjet nozzle becomes unstable, and the print quality of the image may be deteriorated. Specifically, the instability of the emission property means that the liquid droplets from the nozzle must be discharged straight in the direction perpendicular to the nozzle plate surface, and the dispersed pigment having a large particle diameter in the nozzle. May cause sludge to be ejected obliquely, or splashing from the nozzles immediately after the droplets that should be ejected are ejected, and the portion of the medium other than the normal droplet landing position to be smudged with the splash. This is a phenomenon in which a dispersed pigment having a large particle size clogs the nozzle and cannot be discharged. As described above, since the ink performance is deteriorated by storage, the quality cannot be sufficiently ensured for a long period of time, for example, for one year or more.

  On the other hand, the great merit of an ink jet printer is that ink loss is extremely small by printing a necessary amount of ink on a necessary portion on an image recording medium. Is much less than other recording methods such as electrophotography and printing methods using various printing plates. For this reason, there are many cases where ink is stored for a long time in the state of a package, and long-term storage stability is an important quality requirement.

  On the other hand, as a packaging material for foods, various plastic film packaging is used in the literature such as packaging technology manual (edited and published by Japan Packaging Technology Association), transportation / industrial packaging technology (supervised by Junichi Mizuguchi, Fuji Techno Systems Co., Ltd.). Materials are listed. This includes a so-called plastic film material having a thickness of less than 0.1 mm with a low water vapor transmission rate. However, when such a thin film with a low water vapor transmission rate is used as a packaging material for non-aqueous inkjet inks, it is insufficient in strength and occurs during normal transportation and user handling. If the packaging material is destroyed by repeated drop impact and volume expansion and contraction of the ink due to sudden temperature differences in the storage environment, ink leakage may occur and stain surrounding items. There was a serious problem that the organic solvent in the ink melts the article and breaks it. For this reason, for example, it is necessary to wrap and wrap around a plastic film filled with ink with a hard plastic packaging material having sufficient strength. As a result, since the packaging material cost is high and the packaging processing cost is high, the economic burden is large, and as a result, the inkjet printing system has become a hindrance to widespread use in the world. Further, using the material having a low water vapor transmission rate and increasing the thickness of the material in order to increase the strength also caused a significant increase in packaging material costs, and was not completely acceptable from the viewpoint of economy. .

  On the other hand, as a packaging material having sufficient strength and low water vapor transmission rate, it is also possible to use a metal can such as aluminum or iron. However, these packaging materials are expensive and have large mass for transportation. The cost is high and the economic disadvantage is large. In addition, if the metal dissolves in the ink in a small amount during long-term storage, the metal ions and the components of the ink react to generate a precipitate.

Therefore, from an economic point of view, an ink-jet ink package in which ink is filled in a packaging container that is compatible with water vapor permeability, impact strength, and price, and has been stored for a long period of one year or more. However, there has been a strong demand for a non-aqueous inkjet ink package that does not generate precipitates in the ink, does not fluctuate in ink viscosity, and can maintain a good output property.
Japanese translation of PCT publication No. 2002-526631 JP 2005-36199 A

  The present invention has been made in view of the above problems, and has an object of having printability (rubbing resistance, alcohol wiping resistance) on a plastic recording medium such as polyvinyl chloride, excellent safety, and odor. Non-water-based inkjet ink packaging that can be used without any problems, and does not generate precipitates even when the ink is stored for a long period of time, does not fluctuate in ink viscosity, and maintains a good output property. Another object of the present invention is to provide an ink jet recording method.

  The above object of the present invention is achieved by the following configurations.

1. 50% by mass or more of the solvent (A) containing at least a pigment and a fixing resin and comprising one or more compounds selected from the group of compounds represented by the following general formulas (1) and (2) with respect to the total mass of the ink , 90% by mass or less of the non-aqueous ink-jet ink is composed of a material having a water vapor transmission rate of 1.5 g / m ² · 24 hrs or more and 50 g / m ² · 24 hrs or less, and the container has a thickness of 0.1 mm or more, A non-aqueous inkjet ink package, which is filled in a packaging container of 3.0 mm or less.

[Wherein, R ¹ and R ² each represent a methyl group or an ethyl group, and OX ¹ represents an oxyethylene group or an oxypropylene group. ]

[Wherein, R ³ and R ⁴ each represent a methyl group or an ethyl group, and OX ² represents an oxyethylene group or an oxypropylene group. ]
2. The non-aqueous inkjet ink has a moisture absorption increase amount of 2% by mass or more and 5% by mass or less when all the solvents are left in an environment of room temperature 25 ° C. and relative humidity 60% for 14 days. The non-aqueous ink-jet ink package described.

  3. The solvent (A) contained in the non-aqueous ink-jet ink is at least one selected from diethylene glycol diethyl ether, dipropylene glycol dimethyl ether, dipropylene glycol diethyl ether, ethylene glycol diacetate and propylene glycol diacetate. The non-aqueous inkjet ink package according to 1 or 2 above.

  4). The non-aqueous inkjet ink package according to any one of 1 to 3, wherein the packaging container has a thickness of 0.3 mm or more and 3.0 mm or less.

  5). The non-aqueous ink-jet ink contains 1.5% by mass or more and 30% by mass or less of the solvent (B) composed of one or more compounds selected from the compound group represented by the following general formulas (3) and (4). The non-aqueous inkjet ink package according to any one of 1 to 4, which is contained.

[Wherein, R ⁵ and R ⁶ each represent a substituent having 1 to 6 carbon atoms, and R ⁵ and R ⁶ may be bonded to form a ring. ]

[Wherein, R ⁷ and R ⁸ each represent a substituent having 1 to 6 carbon atoms, and R ⁷ and R ⁸ may be bonded to form a ring. ]
6). 6. The non-aqueous inkjet ink package according to any one of 1 to 5, wherein the fixing resin is a resin synthesized by a solution polymerization method.

  7). The fixing resin has a vinyl chloride-vinyl acetate copolymer, vinyl chloride-vinyl acetate-maleic anhydride copolymer, vinyl chloride-vinyl acetate-vinyl alcohol copolymer having a number average molecular weight in the range of 10,000 to 30,000. The non-aqueous inkjet ink package according to any one of 1 to 6 above, which is at least one selected from a polymer and a vinyl chloride-vinyl acetate-hydroxyalkyl acrylate copolymer.

  8). 8. An ink jet recording method for recording an image on a recording medium using the non-aqueous ink-jet ink filled in the non-aqueous ink-jet ink package according to any one of 1 to 7, wherein the recording medium comprises a poly An ink jet recording method comprising at least one selected from vinyl chloride, a resin base material containing no plasticizer, and a recording medium comprising a non-absorbing inorganic base material.

  According to the present invention, it has printability (rubbing resistance, alcohol wiping resistance) on a plastic recording medium such as polyvinyl chloride, is excellent in safety, has no problem of odor, especially when the ink is stored for a long period of time. A non-aqueous inkjet ink package that does not generate precipitates, does not fluctuate in ink viscosity, has excellent emission stability, and does not cause deterioration of scratch resistance when printed using ink after long-term storage; An ink jet recording method using the same can be provided.

  Hereinafter, the best mode for carrying out the present invention will be described in detail.

The non-aqueous inkjet ink package of the present invention (hereinafter also simply referred to as a package) contains at least a pigment and a fixing resin, and is one type selected from the group of compounds represented by the general formulas (1) and (2). A non-aqueous inkjet ink containing the solvent (A) composed of the above compound in an amount of 50% by mass to 90% by mass with respect to the total mass of the ink has a water vapor transmission rate of 1.5 g / m ² · 24 hrs or more and 50 g / m It is characterized by filling a packaging container made of a material of ² · 24 hrs or less and having a container thickness of 0.1 mm or more and 3.0 mm or less.

By storing the non-aqueous ink-jet ink in a packaging body having a configuration defined in the present invention, water vapor permeates through a packaging material having a water vapor transmission rate of 1.5 g / m ² · 24 hrs or more and 50 g / m ² · 24 hrs or less. In this case, the content of the solvent (A) composed of one or more compounds selected from the compound group represented by the general formulas (1) and (2) is 50% by mass or more and 90% by mass or less. It has been found that even when absorbed in ink, the fluctuation of viscosity due to moisture is effectively suppressed, and the deterioration of the emission stability is reduced. Although this is not certain, it is speculated that it is caused by good compatibility between the solvent (A) and moisture. In addition, by making the container thickness within the range specified in the present invention, it is excellent in strength, is not damaged or deformed even with a sudden temperature change during storage or a drop impact, and ink leakage does not occur, and it is safe At the same time, it was not necessary to use an expensive material as a packaging material, and an ink package excellent in economic efficiency could be provided. In addition, surprisingly, an excellent non-aqueous inkjet ink package that does not cause deterioration of scratch resistance when printing is performed using ink after long-term storage, and an inkjet recording method using the same Could be provided. Although this is not certain, it is presumed that unevenness due to secondary aggregation of pigment particles on the surface of the printed image hardly occurs and the flatness is not impaired. The present invention solves the problems of economic efficiency and performance that have hindered the widespread use of inkjet printing systems in the world, and further improves the image forming system for non-absorbable recording media in the world by utilizing inkjet systems. The improvement of convenience can be expected.

  Hereinafter, each component of the present invention will be described.

《Packaging container》
The inkjet ink package of the present invention is characterized by using a packaging container having the following characteristics.

The non-aqueous inkjet packaging container of the present invention is characterized by being composed of a material having a water vapor transmission rate of 1.5 g / m ² · 24 hrs or more and 50 g / m ² · 24 hrs or less. The water vapor transmission rate as used in the present invention is a value measured at a thickness corresponding to 25 μm in an environment of 40 ° C. and a relative humidity of 90%. For example, transport / industrial packaging technology (supervised by Junichi Mizuguchi, Fuji Techno Co., Ltd.) Among materials listed in “Systems”), materials satisfying the above water vapor transmission rate can be used.

  The material satisfying the water vapor transmission rate defined in the present invention is preferably a plastic material from the viewpoint of economy, strength, long-term storage stability of the ink, and considering that it is not dissolved by the ink, for example, low density polyethylene ( LDPE), high density polyethylene (HDPE), polypropylene (PP), polyethylene terephthalate (PET), and the like.

  These materials may be used alone, or may be used in a multilayer structure in which two or more kinds of materials are bonded together. From the viewpoint of economy, it is preferable to use a single unit.

  Among these materials, LDPE and HDPE are preferable from the viewpoint of long-term storage stability and economy, and HDPE is more preferable.

  The thickness of the packaging container according to the present invention is 0.1 mm or more and 3.0 mm or less. More preferably, it is 0.3 mm or more and 3.0 mm or less. If the thickness of the container is 0.1 mm or more, long-term storage stability as an inkjet package is sufficient, and sufficient strength can be obtained, and resistance to vibration during transportation and impact of dropping can be imparted. . On the other hand, if the thickness of the container is 3.0 mm or less, it is preferable from the viewpoint that both long-term storage stability and strength are sufficient, and that the cost of packaging material is excellent.

《Non-aqueous inkjet ink》
[Compounds represented by general formulas (1) and (2)]
The non-aqueous inkjet ink according to the present invention (hereinafter also simply referred to as ink) can contain a non-aqueous solvent, but one or more selected from the compound group represented by the general formulas (1) and (2). It is preferable to contain the solvent (A) which consists of these compounds.

In the general formula (1), R ¹ and R ² each represent a methyl group or an ethyl group, and OX ¹ represents an oxyethylene group or an oxypropylene group.

In the general formula (2), R ³ and R ⁴ each represent a methyl group or an ethyl group, and OX ² represents an oxyethylene group or an oxypropylene group.

  Specific compounds represented by the general formulas (1) and (2) according to the present invention include, for example, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, dipropylene glycol dimethyl ether, dipropylene glycol diethyl ether, ethylene glycol diacetate, propylene Examples thereof include glycol diacetate.

  Among these, the component of the solvent (A) is preferably at least one selected from diethylene glycol diethyl ether, dipropylene glycol dimethyl ether, dipropylene glycol diethyl ether, ethylene glycol diacetate and propylene glycol diacetate. The quick drying property of the ink when printed on vinyl and the long-term storage stability of the inkjet ink package can be further improved. Among them, a particularly preferable solvent (A) is one containing diethylene glycol diethyl ether and ethylene glycol diacetate in a ratio of at least 1: 1 to 10: 1.

  One of the characteristics of the content of the solvent (A) in the ink-jet ink is 50% by mass or more and 90% by mass or less. By using such a solvent configuration, the speed at the time of printing polyvinyl chloride can be increased. In addition to good dryness and emission stability, the ink odor is reduced and contributes to the long-term storage stability of the inkjet ink package, which is an effect of the present invention.

[Evaluation method of moisture absorption increase of mixed solvent]
In the present invention, it is preferable that the amount of increase in moisture absorption of all the solvents when left in an environment of room temperature of 25 ° C. and relative humidity of 60% for 14 days is 2% by mass or more and 5% by mass or less.

  This is achieved by containing 50% by mass or more and 90% by mass or less of the solvent (A) composed of one or more kinds of compounds selected from the compound group represented by the general formulas (1) and (2). The inventor has found that. When the amount of increase in moisture absorption exceeds 5%, sufficient long-term storage stability cannot be obtained in the inkjet ink package according to the configuration of the present invention. On the other hand, in the ink-jet ink containing 50% by mass or more and 90% by mass or less of the solvent (A) composed of one or more compounds selected from the compound group represented by the general formulas (1) and (2), moisture absorption The increase will not be less than 2%. For example, in conventional ink jet inks using glycol acetates, there are cases where an ink having a moisture absorption increase of less than 2% may be obtained. Since it is insufficient, sufficient long-term storage stability cannot be obtained.

  The amount of increase in moisture absorption of all solvents in the present invention is determined by the following method. First, a mixed solvent in which all the solvents contained in the ink are mixed at the same ratio as the composition ratio in the ink is prepared. The water content of all the solvents is measured by the Karl Fischer method. Thereafter, 100 ml of the total solvent is poured into a 200 ml beaker and left in an open system at room temperature of 25 ° C. and a relative humidity of 60% for 14 days. The moisture content of all the solvents after being left is measured again by the Karl Fischer method, and the difference between the moisture content before and after being left as the amount of moisture absorption is determined.

[Other solvents]
In the non-aqueous inkjet ink according to the present invention, in addition to the solvent (A) according to the present invention, a conventionally known solvent may be contained in a range not impairing the object effect of the present invention. Is, for example, alkylene glycol monoalkyl ethers such as diethylene glycol monoethyl ether, triethylene glycol monomethyl ether, dipropylene glycol monomethyl ether, tripropylene glycol monomethyl ether, and alkylene glycol dialkyl ethers such as ethylene glycol dibutyl ether and tetraethylene glycol dimethyl ether. Kind.

  Furthermore, in the ink-jet ink according to the present invention, an organic solvent for imparting vinyl chloride solubility may be added for the purpose of enhancing the adhesion to the vinyl chloride recording medium. In order to achieve better stability, it is preferable to contain a compound as shown below.

  As one of the solvents, a compound represented by the following general formula (5) or (6) can be given.

[Wherein, R ₁ represents an alkylene group having 3 to 11 carbon atoms, and R ₂ represents a hydrogen atom or a methyl group. ]
General formula (6)
R ₃ CON (R ₄ ) ₂
Wherein, R _3, R ₄ each independently represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. ]
Specific examples of the solvent represented by the general formula (5) include β-lactam, 2-pyrrolidone, δ-lactam, ε-caprolactam, laurolactam, N-methyl-2-pyrrolidone and the like.

  Specific examples of the solvent represented by the general formula (6) include N-methylformamide, N, N-dimethylformamide, N, N-diethylformamide, N-methylacetamide, N, N-dimethylacetamide, N, N-diethylacetamide and the like can be mentioned.

  In addition, examples of the soluble solvent for the polyvinyl chloride resin include 1,2-dichloroethane, nitroethane, acetone, methyl ethyl ketone, butyl acetate, dioxane, cyclohexane, cyclohexanone, pyridine, morpholine, diethylene glycol dimethyl ether, and the like.

  Moreover, a lactone type | system | group solvent can be mentioned as another solvent which can be used together.

  The lactone solvent is a compound having a cyclic structure by an ester bond, and includes a 5-membered ring structure γ-lactone, a 6-membered ring structure δ-lactone, a 7-membered ring structure ε-lactone, and the like. Butyrolactone, γ-valerolactone, γ-hexalactone, γ-heptalactone, γ-octalactone, γ-nonalactone, γ-decalactone, γ-undecalactone, δ-valerolactone, δ-hexalactone, δ-heptalactone , Δ-octalactone, δ-nonalactone, δ-decalactone, δ-undecalactone, and ε-caprolactam. The lactone solvent is a γ-lactone having a 5-membered ring structure in a preferred embodiment, and in a more preferred embodiment, γ-butyrolactone and γ-valerolactone.

  Furthermore, the solvent shown below can be mentioned as another solvent which can be used together.

[Compounds Represented by General Formulas (3) and (4)]
The compounds represented by the general formulas (3) and (4) are more preferable from the viewpoint of the effect of the present invention.

In the general formula (3), R ⁵ and R ⁶ each represent a substituent having 1 to 6 carbon atoms, for example, a linear or branched alkyl such as a methyl group, an ethyl group, an n-propyl group, or an isopropyl group. Groups, alkyl groups substituted with heteroatoms such as hydroxyethyl group, acetyl group, and acetonyl group, cyclic groups such as cyclohexyl group and phenyl group, or aromatic substituents, and R ⁵ and R ⁶ are They may be the same or different, and R ⁵ and R ⁶ may be bonded to each other to form a ring.

In the general formula (4), R ⁷ and R ⁸ each represent a substituent having 1 to 6 carbon atoms, for example, a linear or branched alkyl such as a methyl group, an ethyl group, an n-propyl group, or an isopropyl group. Groups, alkyl groups substituted with heteroatoms such as hydroxyethyl group, acetyl group, and acetonyl group, cyclic groups such as cyclohexyl group and phenyl group, or aromatic substituents, and R ⁷ and R ⁸ are They may be the same or different, and R ⁷ and R ⁸ may be bonded to each other to form a ring.

  Examples of the compounds represented by the general formulas (3) and (4) according to the present invention include dimethyl sulfoxide, diethyl sulfoxide, methyl ethyl sulfoxide, diphenyl sulfoxide, tetraethylene sulfoxide, dimethyl sulfone, methyl ethyl sulfone, and methyl-isopropyl. Examples include sulfone, methyl-hydroxyethyl sulfone, and sulfolane.

  The content of the compound (B) in the inkjet ink is preferably 1.5% by mass or more and 30% by mass or less, more preferably 3% by mass or more and 20% by mass or less, and particularly preferably 5% by mass. % Or more and 15% by mass or less. When the content of the compound (B) is 1.5% by mass or more, the solubility of the ink in polyvinyl chloride is sufficient, and scratch resistance and alcohol wiping resistance against polyvinyl chloride can be obtained. Moreover, if it is 3 mass% or more, the abrasion resistance with respect to polyvinyl chloride and alcohol wiping resistance are favorable, and if it is 30 mass% or less, stable emission without causing abnormalities of the inkjet head due to long-term use. It can be performed.

  Next, other components of the ink according to the present invention will be described.

[Pigment]
In the non-aqueous inkjet ink according to the present invention, a pigment is used as a coloring material. By using a pigment as the color material, the weather resistance of the recorded matter recorded on a plastic recording medium such as polyvinyl chloride can be improved.

  As the pigment that can be used in the present invention, conventionally known pigments can be used without particular limitation. For example, organic pigments such as insoluble pigments and lake pigments, and inorganic pigments such as carbon black can be preferably used.

  The insoluble pigment is not particularly limited, for example, azo, azomethine, methine, diphenylmethane, triphenylmethane, quinacridone, anthraquinone, perylene, indigo, quinophthalone, isoindolinone, isoindoline, azine, oxazine, thiazine, Dioxazine, thiazole, phthalocyanine, diketopyrrolopyrrole and the like are preferable.

  Specific pigments that can be preferably used include the following pigments.

  Examples of the magenta or red pigment include C.I. I. Pigment red 2, C.I. I. Pigment red 3, C.I. I. Pigment red 5, C.I. I. Pigment red 6, C.I. I. Pigment red 7, C.I. I. Pigment red 12, C.I. I. Pigment red 15, C.I. I. Pigment red 16, C.I. I. Pigment red 48 (Ca), C.I. I. Pigment red 48 (Mn), C.I. I. Pigment red 48: 1, C.I. I. Pigment red 53: 1, C.I. I. Pigment red 57 (Ca), C.I. I. Pigment red 57: 1, C.I. I. Pigment red 112, C.I. I. Pigment red 122, C.I. I. Pigment red 123, C.I. I. Pigment red 139, C.I. I. Pigment red 144, C.I. I. Pigment red 149, C.I. I. Pigment red 166, C.I. I. Pigment red 168, C.I. I. Pigment red 177, C.I. I. Pigment red 178, C.I. I. Pigment red 184, C.I. I. Pigment red 202, C.I. I. Pigment red 209, C.I. I. Pigment red 222, C.I. I. Pigment red 254, C.I. I. Pigment violet 19 and the like.

  Examples of the pigment for orange or yellow include C.I. I. Pigment orange 31, C.I. I. Pigment orange 43, C.I. I. Pigment yellow 1, C.I. I. Pigment yellow 2, C.I. I. Pigment yellow 3, C.I. I. Pigment yellow 12, C.I. I. Pigment yellow 13, C.I. I. Pigment yellow 14, C.I. I. Pigment yellow 15, C.I. I. Pigment yellow 15: 3, C.I. I. Pigment yellow 16, C.I. I. Pigment yellow 17, C.I. I. Pigment yellow 73, C.I. I. Pigment yellow 74, C.I. I. Pigment yellow 75, C.I. I. Pigment yellow 83, C.I. I. Pigment yellow 93, C.I. I. Pigment yellow 95, C.I. I. Pigment yellow 97, C.I. I. Pigment yellow 98, C.I. I. Pigment yellow 109, C.I. I. Pigment yellow 110, C.I. I. Pigment yellow 114, C.I. I. Pigment yellow 120, C.I. I. Pigment yellow 128, C.I. I. Pigment yellow 129, C.I. I. Pigment yellow 130, C.I. I. Pigment yellow 138, C.I. I. Pigment yellow 147, C.I. I. Pigment yellow 150, C.I. I. Pigment yellow 151, C.I. I. Pigment yellow 154, C.I. I. Pigment yellow 155, C.I. I. Pigment yellow 180, C.I. I. Pigment yellow 185, C.I. I. Pigment yellow 213, C.I. I. And CI Pigment Yellow 214.

  Examples of the pigment for green or cyan include C.I. I. Pigment blue 1, C.I. I. Pigment blue 2, C.I. I. Pigment blue 3, C.I. I. Pigment blue 15, C.I. I. Pigment blue 15: 2, C.I. I. Pigment blue 15: 3, C.I. I. Pigment blue 15: 4, C.I. I. Pigment blue 16, C.I. I. Pigment blue 22, C.I. I. Pigment blue 60, C.I. I. And CI Pigment Green 7.

In addition to the above, when red, green, blue and intermediate colors are required, the following pigments are preferably used alone or in combination. I. Pigment Red 209, 224, 177, 194;
C. I. Pigment Orange 43;
C. I. Vat Violet 3;
C. I. Pigment Violet 19, 23, 37;
C. I. Pigment Green 36, 7;
C. I. Pigment Blue 15: 6;
Etc. are used.

  Examples of black pigments include C.I. I. Pigment black 1, C.I. I. Pigment black 6, C.I. I. Pigment black 7 and the like.

  The content of these pigments in the ink according to the present invention is preferably 2 to 10% by mass. In order to reduce the graininess of the image, a light color ink may be used. In this case, the pigment content is preferably 1/5 to 1/2 with respect to the dark color ink.

  The pigment according to the present invention is preferably used after being dispersed by a disperser together with a pigment derivative having a basic group according to the present invention, a dispersant, and other additives necessary for various desired purposes. As the disperser, conventionally known dispersers such as a ball mill, a sand mill, an attritor, a roll mill, an agitator, a Henschel mixer, a colloid mill, an ultrasonic homogenizer, a pearl mill, a wet jet mill, and a paint shaker can be used.

  The average particle size of the pigment dispersion used in the ink according to the present invention is preferably 10 nm or more and 200 nm or less, and more preferably 50 nm or more and 150 nm or less. By making the average particle size 10 nm or more, aggregation of pigment particles is less likely to occur, and by making the average particle size 200 nm or less, it becomes easy to suppress the phenomenon that the pigment settles when stored over a long period of time. By setting the average particle size in the above range, it becomes easy to obtain an ink having good storage stability.

  The particle size of the pigment dispersion can be measured by a commercially available particle size measuring device using a light scattering method, an electrophoresis method, a laser Doppler method or the like. It is also possible to obtain a particle image with a transmission electron microscope on at least 100 particles and perform statistical processing on the image using image analysis software such as Image-Pro (manufactured by Media Cybernetics). Is possible.

[Pigment derivative having acidic group]
The non-aqueous ink-jet ink according to the present invention can contain a pigment derivative having an acidic group.

  The pigment derivative having an acidic group according to the present invention is one in which an acidic functional group is bonded directly or via a joint to a mother nucleus having a pigment structure. Examples of the acidic functional group include a sulfonic acid group, a carboxylic acid group, a phosphoric acid group, a boric acid group, and a hydroxyl group, preferably a sulfonic acid group and a carboxylic acid group, and more preferably a sulfonic acid group.

  Examples of methods for preparing pigment particles having an acidic functional group on the surface include WO97 / 48769, JP-A-10-110129, JP-A-11-246807, JP-A-11-57458, and JP11-189739. By treating the pigment particle surface described in JP-A-11-323232, JP-A-2000-265094, etc. with an appropriate oxidizing agent, at least a part of the pigment surface has a sulfonic acid group or a salt thereof. A method of introducing an acidic functional group is mentioned. Specifically, a method of oxidizing carbon black with concentrated nitric acid. In the case of a color pigment, it is prepared by oxidizing with sulfamic acid, sulfonated pyridine salt, amidosulfuric acid, etc. in sulfolane or N-methyl-2-pyrrolidone. can do. A pigment dispersion can be obtained by removing and purifying a substance that has been excessively oxidized and becomes water-soluble by these reactions. Moreover, when a sulfonic acid group is introduced to the surface by oxidation, the acidic group may be neutralized with a basic compound as necessary.

  Other methods include a method of adsorbing the pigment derivatives described in JP-A-11-49974, JP-A-2000-273383, JP-A-2000-303014, etc. on the surface of the pigment particles by a treatment such as milling. Examples include a method of dissolving the pigment described in each publication such as 2002-179777, 2002-20141, and the like together with a pigment derivative, followed by crystallization in a poor solvent. Pigment particles having an acidic functional group on the surface can be obtained.

  In the present invention, the acidic functional group may be free or in a salt state, or may have a counter salt. Examples of the counter salt include inorganic salts (lithium, sodium, potassium, magnesium, calcium, aluminum, nickel, ammonium) and organic salts (triethylammonium, diethylammonium, pyridinium, triethanolammonium, etc.), preferably 1 A counter salt having a valence.

  Furthermore, as a pigment derivative having a more preferred acidic group of the present invention, a compound represented by the following general formula (7) can also be used.

General formula (7)
(PX) ^- [N (R ₁₁ , R ₁₂ , R ₁₃ , R ₁₄ )] ⁺
In the above general formula (7), P is azo, benzimidazolone, phthalocyanine, quinacridone, anthraquinone, dioxazine, diketopyrrolopyrrole, quinophthalone, isoindolinone, isoindoline, perylene. , A kind of organic dye residue selected from perinone, flavanthrone, pyranthrone, or anthrapyrimidine, X is a sulfonic acid group or carboxylic acid group, R ₁₁ is an alkyl group having 5 to 20 carbon atoms, R ₁₂ , R ₁₃ and R ₁₄ each independently represents a hydrogen atom or an alkyl group having 1 to 20 carbon atoms.

  In addition, the pigment derivative represented by the general formula (7) exhibits a favorable effect on the scratch resistance and alcohol wiping resistance by salting a pigment derivative having a sulfonic acid group or a carboxylic acid group introduced with an amine. To do. Examples of amines include primary amines such as octylamine and dodecylamine, secondary amines such as dioleylamine and distearylamine, tertiary amines such as dimethyllaurylamine and dimethylstearylamine, trimethylammonium, dimethyldistearylammonium and the like. The primary amine and quaternary amine are preferred.

  The pigment derivative having an acidic group according to the present invention is preferably in the range of 0.2 to 15% by mass, more preferably in the range of 1 to 10% by mass with respect to the total amount of the pigment and the pigment derivative. If the addition amount of the pigment derivative having an acidic group is within the range specified above, the scratch resistance which is the object effect of the present invention can be achieved.

  The pigment contained in the ink according to the present invention and the pigment structure portion of the core of the pigment derivative do not necessarily have the same structure, but considering the hue of the ink finally prepared, the yellow pigment In the case of yellow pigment derivatives, red pigments in the case of red pigments, blue pigment derivatives in the case of blue pigments, those close to the hue of the pigment to be dispersed, or colorless It is preferable to use a pigment in that a pigment dispersion excellent in hue can be obtained.

[Pigment derivative having basic group]
The non-aqueous inkjet ink according to the present invention can contain a pigment derivative having a basic group.

  The pigment derivative having a basic group applicable to the present invention is one in which a basic functional group is bonded to a mother nucleus having a pigment structure directly or through a joint.

  The pigment derivative having a basic group is not particularly limited, but for pigments having a neutral and acidic surface, in addition to the method of treating the surface basic with a known treatment method, A pigment derivative represented by the general formula (8) can be used.

General formula (8)
P- [X-Y-Z-N ( R 15) R 16 ] _v
In the general formula (8), P is an organic pigment residue or heterocyclic residue, X is _{-SO 2 -, - CO 2 -} , - CH 2 -, - CH 2 S -, - CH 2 O -, - Y represents a divalent linking group selected from the group consisting of O—, —COO—, —NH— and —CH ₂ NHCOCH—, wherein Y is a direct bond or —N (R) — (where R is H or the number of carbon atoms. Represents an alkyl group having 1 to 18 or Z—N (R ₁₅ ) R ₁₆ ) or —O—, Z represents an alkylene group having 1 to 6 carbon atoms, and R ₁₅ and R ₁₆ are each independently substituted. Represents an optionally substituted alkyl group having 1 to 18 carbon atoms (R ₁₅ and R ₁₆ may form an optionally substituted ring which may further contain N, O or S), and v represents Represents an integer of 1 to 3;

  Examples of the organic dye residue P include phthalocyanine, insoluble azo, azo lake, anthraquinone, quinacridone, dioxazine, diketopyrrolopyrrole, anthrapyrimidine, anthanthrone, indanthrone, flavanthrone. Type, perinone type, perylene type, thioindigo type and the like. Specific examples of the heterocyclic residue P include thiophene, furan, xanthene, pyrrole, imidazole, isoindoline, isoindolinone, benzimidazolone, indole, quinoline, carbazole, acridine, acridone, and anthraquinone. . When P is a heterocyclic ring, the pigment derivative of the general formula (8) is advantageous in terms of versatility because it is hardly colored.

The _{X, -SO 2 -, - CO} 2 -, - CH 2 -, - CH 2 S -, - CH 2 O -, - O -, - COO -, - NH- and -CH ₂ NHCOCH-, or These combinations may be mentioned, and among them, —SO ₂ —, —CO ₂ —, and —CH ₂ — are preferable. When R ₁₅ and R ₁₆ are alkyl groups, lower alkyl groups such as methyl group, ethyl group, propyl group, and butyl group are preferred. These alkyl groups may be branched within a range of up to 18 carbon atoms and may be substituted. Further, in some cases, R ₁₅ and R ₁₆ may be linked to form a 5-membered or 6-membered heterocyclic ring containing N, O or S.

A pigment derivative having a basic group can be synthesized by various synthetic routes. For example, after introducing a substituent such as —SO ₂ Cl, —COCl, —CH ₂ NHCOCH ₂ Cl, —CH ₂ Cl into the organic dye, the organic dye reacts with the substituent, and the following general formulas (9) to (9) to ( 12) an amine component that forms a substituent represented by, for example, N, N-dimethylaminopropylamine, N-methylpiperazine, diethylamine or 4- [4-hydroxy-6- [3- (dibutylamino) propylamino ] -1,3,5-triazin-2-ylamino] aniline and the like.

In the general formulas (9) to (12), X ′ represents —SO ₂ —, —CO—, —CH ₂ NHCOCH ₂ —, —CH ₂ — or a direct bond, and n represents an integer of 1 to 10. .

R ₁₇ and R ₁₈ are each independently an alkyl group that may be substituted, an alkenyl group that may be substituted, a phenyl group that may be substituted, or a combination of R ₁₇ and R _18. Represents an optionally substituted heterocycle containing additional nitrogen, oxygen or sulfur atoms.

R ₁₉ represents an optionally substituted alkyl group, an optionally substituted alkenyl group, or an optionally substituted phenyl group.

R ₂₀ , R ₂₁ , R ₂₂ and R ₂₃ each independently represents a hydrogen atom, an optionally substituted alkyl group, an optionally substituted alkenyl group or an optionally substituted phenyl group.

Y represents —NR ₂₄ —Z—NR ₂₅ — or a direct bond. R ₂₄ and R ₂₅ each independently represent a hydrogen atom, an optionally substituted alkyl group, an optionally substituted alkenyl group or an optionally substituted phenyl group.

  Z represents an alkylene group that may be substituted, an alkenylene group that may be substituted, or a phenylene group that may be substituted.

  P represents a substituent represented by the following general formula (13) or a substituent represented by the following general formula (14).

In formula, R < ₁₇ > -R < ₂₃ > is synonymous with those in said general formula (9)-(12), respectively.

  Q ′ represents a hydroxyl group, an alkoxyl group, a substituent represented by the general formula (13) or a substituent represented by the general formula (14).

  When the organic dye is an azo dye, the substituent represented by the general formulas (9) to (12) is introduced into the diazo component or the coupling component in advance, and then the coupling reaction is performed, whereby the azo dye is obtained. Pigment derivatives can also be produced.

  In this invention, the pigment derivative which has a basic group has the preferable range of 0.2-15 mass% with respect to the total amount of a pigment and a pigment derivative, More preferably, it is the range of 1-10 mass%. If the addition amount of the pigment derivative having a basic group is within the range specified above, an effect excellent in scratch resistance and drying property can be exhibited.

  The pigment contained in the ink according to the present invention and the pigment structure portion of the core of the pigment derivative do not necessarily have the same structure, but considering the hue of the ink finally prepared, the yellow pigment In the case of yellow pigment derivatives, red pigments in the case of red pigments, blue pigment derivatives in the case of blue pigments, those close to the hue of the pigment to be dispersed, or colorless It is preferable to use a pigment in that a pigment dispersion excellent in hue can be obtained.

(Pigment dispersant)
In the ink according to the present invention, a surfactant, a polymer dispersant, or the like can be used as the pigment dispersant. Polymer dispersing agents include (meth) acrylic resins, styrene- (meth) acrylic resins, hydroxyl group-containing carboxylic acid esters, salts of long-chain polyaminoamides and high molecular weight acid esters, salts of high molecular weight polycarboxylic acids, long Salts of chain polyaminoamides and polar acid esters, high molecular weight unsaturated acid esters, condensates or salt formations of polyesters having polyallylamine and free carboxylic acids, modified polyurethanes, modified polyacrylates, polyether ester type anionic activators , Naphthalenesulfonic acid formalin condensate salt, aromatic sulfonic acid formalin condensate salt, polyoxyethylene alkyl phosphate ester, polyoxyethylene nonylphenyl ether, stearylamine acetate, pigment derivatives and the like.

  Specifically, Jonkrill (manufactured by Johnson Polymer), Anti-Terra-U (manufactured by BYK Chemie), Disperbyk (manufactured by BYK Chemie), Efka (manufactured by Efka CHEMICALS), Floren (manufactured by Kyoeisha Chemical), Disparon (manufactured by Enomoto Kasei Co., Ltd.), Demole (manufactured by Kao Corporation), homogenol, Emulgen (manufactured by Kao Corporation), Solspers (manufactured by Avisia), Nikkor (manufactured by Nikko Chemical Co., Ltd.), Ajispur (Ajinomoto Finetech), etc. It is done.

  The content of the dispersant in the non-aqueous inkjet ink according to the present invention is preferably added in the range of 10% by mass to 200% by mass with respect to the pigment. By setting the content to 10% by mass or more, the pigment dispersion stability is enhanced, and by setting the content to 200% by mass or less, the ink ejection from the inkjet head is easily stabilized.

[Fixing resin]
Next, the fixing resin according to the present invention will be described.

  In the non-aqueous inkjet ink according to the present invention, various fixing resins (hereinafter also simply referred to as “resins”) are added in order to improve fixability when recording on a plastic recording medium such as polyvinyl chloride.

  Examples of the resin to be added include acrylic resins, polyester resins, polyurethane resins, vinyl chloride resins, vinyl chloride-vinyl acetate copolymer resins, and the like.

  Specifically, acrylic resins such as John Crill (manufactured by Johnson Polymer Co., Ltd.), ESREC P (manufactured by Sekisui Chemical Co., Ltd.), polyester resins such as Elitel (manufactured by Unitika Ltd.) and Byron (manufactured by Toyobo Co., Ltd.), Byron UR ( Toyobo Co., Ltd.), NT-Hilamic (Daiichi Seika Co., Ltd.), Crisbon (Dainippon Ink Chemical Co., Ltd.), Nipporan (Nippon Polyurethane Co., Ltd.) and other polyurethane resins, SOLBIN (Nisshin Chemical Co., Ltd.), Vinyl Blanc (Nissin Chemical Industry Co., Ltd.), Saran Latex (Asahi Kasei Chemicals Co., Ltd.), Sumielite (Sumitomo Chemical Co., Ltd.), Sekisui PVC (Sekisui Chemical Co., Ltd.), UCAR (Dow Chemical Co., Ltd.) Can be mentioned.

  The fixing resin acts as a binder that adheres a coloring material such as a pigment to the recording medium after printing. The larger the molecular weight of the fixing resin, the better the adhesion and durability. In addition, the smaller the molecular weight, the lower the viscosity of the ink. However, the lower the viscosity, the lower the energy required for ejecting the ink during printing, so that the inkjet head is not burdened and it is easier to eject stably. Therefore, if the number average molecular weight is 10,000 or more, the fixability after printing is sufficiently exhibited, and if it is 30000 or less, it does not impose a load on the ejection of the ink, which is preferable.

  Particularly preferred fixing resins have a number average molecular weight in the range of 10,000 to 30,000, and compositions include vinyl chloride-vinyl acetate copolymer, vinyl chloride-vinyl acetate-maleic anhydride copolymer, vinyl chloride-vinyl acetate- At least one resin selected from vinyl alcohol copolymer and vinyl chloride-vinyl acetate-hydroxyalkyl acrylate copolymer, vinyl chloride-vinyl acetate copolymer and vinyl chloride-vinyl acetate-maleic anhydride copolymer These vinyl chloride-vinyl acetate copolymers and vinyl chloride-vinyl acetate-maleic anhydride copolymers may be mixed with acrylic resins, polyester resins, polyurethane resins, etc. May be used.

  By adding these fixing resins to the ink according to the present invention, the emission stability, scratch resistance and alcohol wiping resistance can be improved in a balanced manner.

  The alcohol wiping resistance referred to in the present invention is resistance to disturbance such as image peeling when wiping the surface of the image with ethanol or a mixed solvent of ethanol and water. Wipe off dirt on the image surface with alcohol for posters for outdoor use. It is a user need for that.

  As a method for synthesizing the fixing resin according to the present invention, a suspension polymerization method, an emulsion polymerization method, a solution polymerization method, and the like can be applied without particular limitation. Among them, the solution polymerization method is preferable.

  The solution polymerization method is one of the methods used for radical polymerization of a monomer having a vinyl group. The monomer and initiator are dissolved in a solvent in which the polymer to be generated is soluble, and the polymerization is performed by heating. Is the method.

  The fixing resin synthesized by the solution polymerization method has high solubility even if it has a relatively high molecular weight, and more resin can be contained in the ink, so that the scratch resistance can be improved.

  The content of the fixing resin in the ink according to the present invention is preferably 1 to 10% by mass. When the content is 1% by mass or more, the image weather resistance when recorded on polyvinyl chloride is enhanced, and when the content is 10% by mass or less, the ink ejection from the inkjet head is easily stabilized, and more preferable. The range of content is 3-7 mass%.

[Other additives]
In the non-aqueous ink jet ink according to the present invention, in addition to the above description, according to the purpose of improving the emission stability, print head and ink cartridge compatibility, storage stability, image storage stability, and other various performances as necessary. Various known additives such as viscosity modifiers, specific resistance modifiers, film forming agents, ultraviolet absorbers, antioxidants, anti-fading agents, anti-fouling agents, rust inhibitors, etc. are appropriately selected and used. Can do.

<Inkjet recording method>
The ink-jet head used when forming the image by discharging the non-aqueous ink-jet ink according to the present invention may be an on-demand system or a continuous system. In addition, as a discharge method, an electro-mechanical conversion method (for example, a single cavity type, a double cavity type, a bender type, a piston type, a shear mode type, a shared wall type, etc.), an electro-thermal conversion method (for example, thermal ink jet) Any ejection method such as a mold, a bubble jet (registered trademark) mold, or the like may be used.

  In the ink jet recording method using the non-aqueous ink jet ink according to the present invention, for example, an ink jet recording image is obtained by ejecting ink from an ink jet head based on a digital signal and attaching it to a recording medium by a printer or the like loaded with ink jet ink. Is obtained. In order to quickly and surely dry the ink adhered to the recording medium, a method of forming an image by increasing the surface temperature of the recording medium is preferable.

  The surface temperature is adjusted according to the durability of the recording medium and the drying property of the ink used, but is preferably 40 to 100 ° C. In particular, when polyvinyl chloride is used as the recording medium, increasing the surface temperature improves the wettability of the ink with respect to the surface of the recording medium. Therefore, it is more preferable to record at a higher surface temperature.

  Depending on the brand of the recording medium made of polyvinyl chloride, there may be a difference in wettability and ink drying, so the surface temperature may be adjusted according to the characteristics of each medium.

  When recording is performed by increasing the surface temperature of the recording medium, it is preferable to mount a heater on the ink jet recording apparatus, and by heating the recording medium before or during transport of the recording medium, the surface temperature of the recording medium alone by the ink jet recording apparatus Can be adjusted.

〔recoding media〕
In the ink jet recording method of the present invention, when an image is recorded on a recording medium using the non-aqueous ink jet ink according to the present invention, polyvinyl chloride, a resin base material not containing a plasticizer, and a non-absorbing property are used as the recording medium. It is characterized by using at least one kind of recording medium selected from recording media having the inorganic base material as a constituent element.

  Specific examples of polyvinyl chloride, which is one of the recording media used in the ink jet recording method of the present invention, include SOL-371G, SOL-373M, SOL-4701 (manufactured by Big Technos Co., Ltd.), glossy PVC (Co., Ltd.). Systemgraph Co., Ltd.), KSM-VS, KSM-VST, KSM-VT (above, manufactured by Kimoto Co., Ltd.), J-CAL-HGX, J-CAL-YHG, J-CAL-WWWG (above, Showa Co., Ltd.) (Made in Osaka), BUS MARK V400 F vinyl, litecal V-600F vinyl (above, made by Flexcon), FR2 (made by Hanwha), LLBAU13713, LLSP20133 (above, made by Sakurai), P-370B, P-400M ( As described above, manufactured by Kambo Plus Co., Ltd.), S02P, S12 , S13P, S14P, S22P, S24P, S34P, S27P (above, manufactured by Grafityp), P-223RW, P-224RW, P-249ZW, P-284ZC (above, manufactured by Lintec Corporation), LKG-19, LPA- 70, LPE-248, LPM-45, LTG-11, LTG-21 (above, manufactured by Shinsei Co., Ltd.), MPI3023 (manufactured by Toyo Corporation), Napoleon Gloss gloss PVC (manufactured by Futaki Electronics Co., Ltd.) , JV-610, Y-114 (above, manufactured by ICC Corporation), NIJ-CAPVC, NIJ-SPVCGT (above, manufactured by Nichie Corporation), 3101 / H12 / P4, 3104 / H12 / P4, 3104 / H12 / P4S, 9800 / H12 / P4, 3100 / H12 / R2, 3101 / H12 / R2, 3104 / H12 / R2, 1445 / H14 / P3, 1438 / One Way Vision (manufactured by Inetrcoat), JT5129PM, JT5728P, JT5822P, JT5829P, JT5829R, JT5829PM, JT5829PM, JM59t MPI1005, MPI1900, MPI2000, MPI2001, MPI2002, MPI3000, MPI3021, MPI3500, MPI3501 (above, manufactured by Avery), AM-101G, AM-501G (above, manufactured by Ginichi Co., Ltd.), FR2 (Hanfa Japan Co., Ltd.), AY-15P, AY-60P, AY-80P, DBSP137GGH, DBSP137GGL SJT-V200F, SJT-V400F-1 (above, manufactured by Hiraoka Orizome Co., Ltd.), SPS-98, SPSM-98, SPSH-98, SVGL-137, SVGS-137, MD3-200 MD3-301M, MD5-100, MD5-101M, MD5-105 (manufactured by Metamark), 640M, 641G, 641M, 3105M, 3105SG, 3162G, 3164G, 3164M, 3164XG, 3164XM, 3165G, 3165SG, 3165M, 3169M, 3451SG, 3551G, 3551M, 3631, 3641M, 3651G, 3651M, 3651SG, 3951G, 3641M (manufactured by Orafol), SVTL-HQ130 (manufactured by Lamy Corporation), S 300 GWF, SPCLEARAD vinyl (above, manufactured by Catalina), RM-SJR (produced by Ryoyo Corporation), Hi Lucky, New Lucky PVC (above, made by LG), SIY-110, SIY-310, SIY-320 ( As described above, Sekisui Chemical Co., Ltd., PRINT MI Frontlit, PRINT XL Light weight banner (hereinafter, manufactured by Endutex), RIJET 100, RIJET 145, RIJET 165 (above, manufactured by Ritrama), NM-SG, NM-SM NEIEI KAKO Co., Ltd.), LTO3GS (Lukio Co., Ltd.), Easy Print 80, Performance Print 80 (above, Jetgraph Co., Ltd.), DSE 550, DSB 550, DSE 80 0G, DSE 802/137, V250WG, V300WG, V350WG (above, manufactured by Hexis), Digital White 6005PE, 6010PE (above, made by Multifix), and the like.

  Moreover, as a recording medium having a resin base material containing no plasticizer or a non-absorbing inorganic base material as a constituent element, the following various base materials are used as constituent elements, and one kind of base material is used alone, or a plurality of kinds are used. These substrates can be used in combination. Examples of the resin base material containing no plasticizer used in the present invention include ABS resin, polycarbonate (PC) resin, polyacetal (POM) resin, polyamide (PA) resin, polyethylene terephthalate (PET) resin, and polyimide (PI). Examples thereof include a resin, an acrylic resin, a polyethylene (PE) resin, a polypropylene (PP) resin, and a hard polyvinyl chloride (PVC) resin that does not contain a plasticizer.

  These resins are characterized by not containing a plasticizer, but there are no particular restrictions on other properties such as thickness, shape, color, softening temperature, and hardness.

  The recording medium used in the present invention is preferably ABS resin, PET resin, PC resin, POM resin, PA resin, PI resin, hard PVC resin containing no plasticizer, acrylic resin, PE resin, or PP resin. More preferred are ABS resin, PET resin, PC resin, PA resin, hard PVC resin not containing plasticizer, and acrylic resin.

  Moreover, as a non-absorbing inorganic base material used for this invention, a metal plate, such as a glass plate, iron, and aluminum, a ceramic plate etc. are mentioned, for example. These inorganic substrates are characterized by not having an ink-absorbing layer on the surface. These non-absorbing inorganic base materials are not particularly limited with respect to other properties such as thickness, shape, color, softening temperature, and hardness.

  EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited thereto. In addition, although the display of "part" or "%" is used in an Example, unless otherwise indicated, "part by mass" or "mass%" is represented.

  Further, the pigment dispersant and fixing resin described below were used after diluting the low boiling point solvent by distillation under reduced pressure and diluting with an organic solvent used for dispersion so that the solid content was 20% by mass. Hereinafter, the amounts of the pigment dispersant and the fixing resin used represent solid content conversion values.

Example 1
<Preparation of ink>
[Preparation of Ink 1]
(Preparation of pigment dispersion 1)
C. I. 10 parts of Pigment Blue 15: 3 (hereinafter abbreviated as PB15: 3), 5 parts of Solsperz 24000 (manufactured by Lubrizol) as a pigment dispersant, and 10 parts of dimethyl sulfoxide (S-1) as Compound (B) Part, 60 parts of diethylene glycol diethyl ether as solvent (A) and 15 parts of ethylene glycol diacetate are mixed, and a horizontal bead mill (system zeta mini manufactured by Ashizawa) filled with zirconia beads having a diameter of 0.5 mm by volume is filled. Then, the zirconia beads were removed to obtain pigment dispersion 1.

(Preparation of resin solution 1)
10 parts dimethyl sulfoxide as compound (B), 65 parts diethylene glycol diethyl ether and 15 parts ethylene glycol diacetate as solvent (A), vinyl chloride-vinyl acetate copolymer synthesized by solution polymerization method as fixing resin 10 parts of the product (trade name VYHD, number average molecular weight 22000, manufactured by Dow Chemicals) were mixed and dissolved to prepare Resin Solution 1.

(Preparation of ink)
While stirring 50 parts of the resin solution 1, 50 parts of the pigment dispersion 1 was mixed and then filtered through a 0.8 μm filter to obtain ink 1.

[Preparation of inks 2-33]
In the preparation of the ink 1, the pigment type, the fixing resin type, the type and addition amount of the compound (B), the type and addition amount of the solvent (A), the type and addition amount of other solvents are shown in Tables 1 and 2. Inks 2 to 36 were prepared in the same manner except that the changes were made.

[Moisture absorption increase]
In accordance with the method described above, the amount of increase in moisture absorption of all solvents was measured by the Karl Fischer method when left for 14 days in an environment of room temperature of 25 ° C. and relative humidity of 60%. As a result of the measurement, the inks 1 to 34 were numerical values within the range of 2 to 5% which is the range of the present invention. Ink 35 and ink 36 were numerical values of less than 2%, which are outside the scope of the present invention.

  In addition, the detail of each additive described by the abbreviation in Table 1 and Table 2 is as follows. In addition, the numerical value of content of Table 1 and Table 2 is the mass%.

[Pigment]
PB15: 3; C.I. I. Pigment Blue 15: 3
PY150; C.I. I. Pigment Yellow 150
PR122; C.I. I. Pigment Red 122
CB: Carbon black [Fixing resin]
PVC: Solution polymerization vinyl chloride-vinyl acetate copolymer
(Product name VYHD, manufactured by Dow Chemicals)
Acrylic: butyl methacrylate-methyl methacrylate copolymer
(Product name DEGLAN P24 manufactured by Degussa)
[Solvent (A)]
DEGEDE: Diethylene glycol diethyl ether EGDAc: ethylene glycol diacetate DEGDME: diethylene glycol dimethyl ether PGDAc: propylene glycol diacetate DPGDEE: dipropylene glycol diethyl ether DPGDME: dipropylene glycol dimethyl ether [Compound (B)]
S-1: Dimethyl sulfoxide S-2: Di-n-propyl sulfoxide S-3: Di-n-butyl sulfoxide S-4: Diphenyl sulfoxide S-5: Tetramethylene sulfoxide S-6: Dimethyl sulfone S-7: Di -N-propyl sulfone S-8: methyl isopropyl sulfone S-9: methyl hydroxyethyl sulfone S-10: sulfolane [other solvents]
TEGDME: Tetraethylene glycol dibutyl ether DPGMEAc: Dipropylene glycol monomethyl ether acetate DEGDBE: Diethylene glycol dibutyl ether EGBAc: Ethylene glycol monobutyl ether acetate NMP: N-methylpyrrolidone γBL: γ-butyrolactone DMI: 1,3-dimethyl-2-imidazolidi Non 《Preparation of ink packaging body》
Using each of the inks prepared above, 900 ml of ink was filled in a packaging container having a material of Table 3 and a container thickness of 1 liter, and sealed to prepare ink packaging bodies 1 to 47.

<Evaluation of ink package>
Each of the prepared ink packages was evaluated according to the following methods.

[Preservation of ink package]
Each ink package was stored for 2 weeks in a storage environment at a temperature of 70 ° C. and a relative humidity of 60%.

[Evaluation of ink viscosity stability]
For each ink before and after storage of the ink package, the viscosity at 25 ° C. is measured using a vibratory viscometer (VISCOMATE VM-1G-MH, manufactured by YAMAICHI.CO.LTD), and the rate of change in ink viscosity before and after storage is reduced. Obtained according to the formula.

Viscosity change rate (%) = [(ink viscosity after storage−ink viscosity before storage) / ink viscosity before storage] × 100
Next, based on the measured viscosity change rate, ink viscosity stability was evaluated according to the following criteria.

◎: No change in ink viscosity before and after storage of ink package ○: Change rate of ink viscosity less than + 3% before and after storage of ink package △: Change rate of ink viscosity before and after storage of ink package Is + 3% or more and less than + 5% x: The change rate of ink viscosity is + 5% or more before and after storage of the ink package [Evaluation of emission stability]
Piezo head having nozzle diameter of 28 μm, driving frequency of 15 kHz, number of nozzles of 512, minimum liquid amount of 14 pl, nozzle density of 180 dpi (dpi represents the number of dots per 2.54 cm), and Japanese Patent Application Laid-Open No. 2002-363469 Using the strobe light emission type ink flight observation device shown in FIG. 2, the ejection cycle and the light emission cycle are synchronized, and the ink flight state before and after storage of each ink package is monitored by a CCD camera. The emission stability in the environment was evaluated according to the following criteria.

A: The degree of occurrence of splash does not change before and after storage of the ink package. Even if ejection is stopped for 3 minutes and resumed, the ink droplets are ejected normally, and there is no change in the number of nozzles that cause bending, missing, speed variation, etc. ○: Before and after storing the ink package The degree of occurrence does not change. The change in the number of nozzles that cause bending, missing, speed variation, etc. when the ejection is resumed after stopping for 3 minutes is within + 5% before and after storage of the ink package. Δ: The degree of occurrence of splash before and after storage of the ink package. An acceptable level of slight change. The change in the number of nozzles that cause bending, missing, speed variation, etc. when the ejection is resumed after stopping for 3 minutes is within + 10% before and after storage of the ink package ×: The degree of occurrence of splash before and after storage of the ink package Changes and deteriorates to an unacceptable level. When ejection is resumed after stopping for 3 minutes, the change in the number of nozzles that cause bending, missing, speed variation, etc. before and after storage of the ink package has deteriorated by more than + 10%. << Evaluation of formed image >>
[Image formation]
Each ink is supplied to an on-demand type ink jet printer equipped with a piezo head having a nozzle diameter of 28 μm, a drive frequency of 15 kHz, a nozzle number of 512, a minimum liquid amount of 14 pl, a nozzle density of 180 dpi, and a heater having a maximum recording density of 1440 × 1440 dpi. Ink before and after storage of the package was loaded. Next, each ink was ejected, and a solid image of 10 cm × 10 cm was recorded on JT5929PM (manufactured by Mactac) which is a recording medium made of polyvinyl chloride. During printing, the recording medium was heated from the back side, and the heater temperature was set so that the surface temperature of the recording medium during image recording was 45 ° C. The surface temperature of the recording medium was measured using a non-contact thermometer (IT-530N type, manufactured by Horiba, Ltd.).

[Evaluation of image]
According to the above method, each image prepared with ink before and after storage of the ink package was evaluated according to the following method. In all cases, the performance of Δ or higher was regarded as an acceptable level.

<Evaluation of scratch resistance>
The surface of the image recorded on polyvinyl chloride was rubbed 50 times with dry cotton, and the difference in image density before and after rubbing was determined. Based on this result, scratch resistance 1 was evaluated according to the following criteria.

◎: Image density difference before and after rubbing does not change before and after storage of ink packaging body ○: Image density difference between before and after ink packaging storage and within −5% deterioration before and after rubbing Δ: Storage of ink packaging body Deterioration within -10% of difference in image density before and after rubbing before and after rubbing: Deterioration of difference in image density before and after rubbing before and after ink package storage was over -10%. Table 3 shows.

  As is apparent from the results shown in Table 3, the ink package having the structure defined in the present invention has less variation in viscosity before and after storage and less deterioration of the ink output property than the comparative example. It can be seen that there is little deterioration in image abrasion resistance when an image is recorded on polyvinyl chloride as a recording medium.

Example 2
<Preparation of ink>
[Preparation of inks 34 to 59]
In the preparation of the ink 1 described in Example 1, the pigment type, the fixing resin type, the type and addition amount of the solvent (A), the type and addition amount of the compound (B), the type and addition amount of the other solvent are as follows. Inks 37 to 62 were prepared in the same manner except that the changes were made as described in Table 4.

[Measurement of increase in moisture absorption]
In accordance with the method described above, the amount of increase in moisture absorption of all solvents was measured by the Karl Fischer method when left for 14 days in an environment of room temperature of 25 ° C. and relative humidity of 60%. As a result of the measurement, the inks 37 to 62 were numerical values within the range of 2 to 5% which is the range of the present invention.

  In addition, the detail of each additive described by the abbreviation in Table 4 is as follows. Moreover, the numerical value of content of Table 4 is the mass%.

[Fixing resin]
mPVC: solution polymerization vinyl chloride-vinyl acetate-maleic anhydride copolymer
(Product name VMCC, manufactured by Dow Chemicals)
sPVC: suspension polymerization vinyl chloride-vinyl acetate copolymer
(Product name SOLBIN TAO, manufactured by Nissin Chemical)
Except for the fixing resin, details of each additive described in abbreviations in Table 4 are the same as those described in Example 1.

<Evaluation of ink>
For each of the inks prepared above, ink packaging bodies 48 to 73 were prepared in the same manner as in Example 1, and the ink packaging bodies were stored in the same manner as in Example 1 and evaluated. However, the scratch resistance was evaluated by the scratch resistance 2 shown below.

<Evaluation of scratch resistance 2>
The image surface recorded on polyvinyl chloride was rubbed 80 times with dry cotton, and the difference in image density before and after rubbing was determined. Based on this result, scratch resistance 2 was evaluated according to the following criteria. The scratch resistance 2 is a more severe evaluation condition because the number of times of rubbing is larger than the scratch resistance of Example 1.

◎: Image density difference before and after rubbing does not change before and after storage of ink packaging body ○: Image density difference between before and after ink packaging storage and within −5% deterioration before and after rubbing Δ: Storage of ink packaging body Deterioration within -10% of difference in image density before and after rubbing before and after rubbing: Deterioration of difference in image density before and after rubbing before and after ink package storage was over -10%. Table 5 shows.

  As is apparent from the results shown in Table 5, the ink package having the configuration defined in the present invention has less variation in viscosity before and after storage, less deterioration in ink emission properties, and a comparative example, and Surprisingly, it can be seen that there is little deterioration in image abrasion resistance when an image is recorded on polyvinyl chloride as a recording medium. It can also be seen that by using a resin synthesized by a solution polymerization method as a fixing resin, more resin can be contained in the ink without affecting the deterioration of the light emission property, and the abrasion resistance is further improved. .

Example 3
Table 6 shows an image forming method similar to that in Example 1, using the ink packaging bodies 1, 46, and 47 described in Example 1 before and after being stored by the same storage method as in Example 1. An image was printed and recorded on a recording medium comprising a resin substrate not containing a plasticizer and a non-absorbing inorganic substrate as shown in the following, and scratch resistance 1 was evaluated in the same manner as in Example 1.

  Table 6 shows the obtained evaluation results.

  As is apparent from the results shown in Table 6, the ink package of the present invention can be used even when image recording is performed on a recording medium comprising a resin base material that does not contain a plasticizer and a non-absorbing inorganic base material. It can be seen that there is little deterioration of scratching.

Claims (8)

50% by mass or more of the solvent (A) containing at least a pigment and a fixing resin and comprising one or more compounds selected from the group of compounds represented by the following general formulas (1) and (2) with respect to the total mass of the ink , 90% by mass or less of the non-aqueous ink-jet ink is composed of a material having a water vapor transmission rate of 1.5 g / m ² · 24 hrs or more and 50 g / m ² · 24 hrs or less, and the container has a thickness of 0.1 mm or more, A non-aqueous inkjet ink package, which is filled in a packaging container of 3.0 mm or less.
[Wherein, R ¹ and R ² each represent a methyl group or an ethyl group, and OX ¹ represents an oxyethylene group or an oxypropylene group. ]
[Wherein, R ³ and R ⁴ each represent a methyl group or an ethyl group, and OX ² represents an oxyethylene group or an oxypropylene group. ]   The non-aqueous inkjet ink has a moisture absorption increase amount of 2% by mass or more and 5% by mass or less when all the solvents are left in an environment of room temperature 25 ° C. and relative humidity 60% for 14 days. The non-aqueous inkjet ink package according to claim 1.   The solvent (A) contained in the non-aqueous ink-jet ink is at least one selected from diethylene glycol diethyl ether, dipropylene glycol dimethyl ether, dipropylene glycol diethyl ether, ethylene glycol diacetate and propylene glycol diacetate. The non-aqueous inkjet ink package according to claim 1 or 2.   The non-aqueous inkjet ink package according to any one of claims 1 to 3, wherein the packaging container has a thickness of 0.3 mm or more and 3.0 mm or less. The non-aqueous ink-jet ink contains 1.5% by mass or more and 30% by mass or less of the solvent (B) composed of one or more compounds selected from the compound group represented by the following general formulas (3) and (4). The non-aqueous inkjet ink package according to any one of claims 1 to 4, wherein the package is contained.
[Wherein, R ⁵ and R ⁶ each represent a substituent having 1 to 6 carbon atoms, and R ⁵ and R ⁶ may be bonded to form a ring. ]
[Wherein, R ⁷ and R ⁸ each represent a substituent having 1 to 6 carbon atoms, and R ⁷ and R ⁸ may be bonded to form a ring. ]   The non-aqueous inkjet ink package according to any one of claims 1 to 5, wherein the fixing resin is a resin synthesized by a solution polymerization method.   The fixing resin has a vinyl chloride-vinyl acetate copolymer, vinyl chloride-vinyl acetate-maleic anhydride copolymer, vinyl chloride-vinyl acetate-vinyl alcohol copolymer having a number average molecular weight in the range of 10,000 to 30,000. The non-aqueous inkjet ink according to any one of claims 1 to 6, wherein the non-aqueous inkjet ink is at least one selected from a polymer and a vinyl chloride-vinyl acetate-hydroxyalkyl acrylate copolymer. Packaging body.   An inkjet recording method for recording an image on a recording medium using the non-aqueous inkjet ink filled in the non-aqueous inkjet ink package according to any one of claims 1 to 7, An ink jet recording method, wherein the recording medium is at least one selected from polyvinyl chloride, a recording medium containing no plasticizer and a non-absorbing inorganic base material.