JP7347050B2 - Ink set, pre-treatment liquid and ink set, printing method, and printing device - Google Patents

Description

The present invention relates to an ink set, a pretreatment liquid and ink set, a printing method, and a printing apparatus.

In recent years, as the uses of inkjet printers have diversified, the substrates on which they are printed have also diversified. For example, attempts have been made to print on non-permeable substrates such as plastic films.

When printing on the non-permeable base material, the liquid on the base material may not penetrate into the base material and may be difficult to dry, and if drying is insufficient, peeling or show-through of the image becomes a problem.

In order to solve the above problems, for example, a hot roll that heats the base material to which ink is applied while contacting the base material, and a first hot air that blows hot air to the surface of the base material to which the ink is applied while being conveyed while contacting the hot roll. A drying device has been proposed that includes a blowing means and a second hot air blowing means that is provided downstream of the first hot air blowing means in the conveying direction of the substrate and blows hot air at a higher temperature than the first hot air blowing means. (For example, see Patent Document 1).

SUMMARY OF THE INVENTION An object of the present invention is to provide a printing device that is less likely to cause deformation and wrinkles of a substrate upon completion of printing, has excellent drying properties, and can suppress the occurrence of blocking.

ただし、前記数式（１）中、前記「測定結果から得られるインクの減量率（％）」とは、インクの熱重量測定の結果得られるインクの減量率である。前記「飽和減量率（％）」とは、測定結果から５分ごとのインクの減量率の差分を算出し、前記差分の絶対値が０．１％未満となる測定時間におけるインクの減量率（％）である。
［測定条件］
・温度プログラム：設定温度１００℃
・昇温速度：１０℃／分
・昇温後の保持時間：７０分
・測定開始温度：２５℃
・制御熱電対：炉
・パン：Ａｌ（アルミニウム）
・試料量：１０ｍｇ±０．３ｍｇ A printing apparatus of the present invention as a means for solving the above problem is a printing apparatus having an ink and a drying mechanism for drying a base material to which the ink has been applied, the drying mechanism for drying a base material to which the ink has been applied. non-contact heating means for heating the surface of the base material to which the ink is applied in a non-contact manner; and contact heating means for contacting the back side of the surface of the base material to which the ink is applied; , the non-contact heating means is a drying mechanism with a higher heating temperature,
The ink contains a coloring material, a resin, water, and an organic solvent, and the organic solvent includes at least one organic solvent having a boiling point of 180°C or higher, and the organic solvent has a boiling point of 180°C or higher based on the total amount of the ink. The content of the solvent is 15% by mass or more, and the ink is measured when the weight loss rate A (unit %) determined by the following formula (1) is -95% in thermogravimetric measurement TG under the following measurement conditions. The time is 30 minutes or less.

However, in the above formula (1), the "ink loss rate (%) obtained from the measurement results" is the ink weight loss rate obtained as a result of thermogravimetric measurement of the ink. The above-mentioned "saturated weight loss rate (%)" is calculated by calculating the difference in ink weight loss rate every 5 minutes from the measurement results, and the ink weight loss rate (%) during the measurement time when the absolute value of the difference is less than 0.1%. %).
[Measurement condition]
・Temperature program: Set temperature 100℃
・Heating rate: 10℃/min
・Holding time after heating up: 70 minutes
・Measurement start temperature: 25℃
・Control thermocouple: Furnace
・Bread: Al (aluminum)
・Sample amount: 10mg±0.3mg

According to the present invention, it is possible to provide a printing device that is less likely to cause deformation and wrinkles of the base material at the end of printing, has excellent drying properties, and can suppress the occurrence of blocking.

FIG. 1 is a schematic diagram illustrating an example of the configuration of an image forming apparatus according to the first embodiment. FIG. 2 is a block diagram showing an example of the hardware configuration of a control device included in the image forming apparatus of the first embodiment. FIG. 3 is a block diagram showing an example of the functional configuration of a control device included in the image forming apparatus of the first embodiment. FIG. 4 is a schematic diagram illustrating an example of the configuration of the drying device of the first embodiment. FIG. 5 is a schematic diagram illustrating the state of drying by the drying apparatus of the first embodiment. FIG. 6 is a schematic perspective view illustrating an example of a configuration for detecting the temperature of the drum heater in the drying apparatus of the first embodiment. FIG. 7 is a diagram illustrating the elongation of the base material when the base material is heated while applying tension necessary for conveyance. FIG. 8 is a schematic diagram illustrating the mechanism of high-speed drying that suppresses elongation of the base material by the drying device of the first embodiment. FIG. 9 is a schematic side view showing an example of a printing device according to the present invention. FIG. 10 is a schematic side view showing another example of the printing device according to the present invention.

ただし、前記数式（１）中、前記「測定結果から得られるインクの減量率（％）」とは、インクの熱重量測定の結果得られるインクの減量率である。前記「飽和減量率（％）」とは、測定結果から５分ごとのインクの減量率の差分を算出し、前記差分の絶対値が０．１％未満となる測定時間におけるインクの減量率（％）である。 (Printing device and printing method)
The printing device of the present invention includes ink and a drying mechanism that dries a base material to which the ink is applied, the drying mechanism drying a surface of the base material to which the ink is applied. It has a non-contact heating means that heats by contact, and a contact heating means that contacts the back side of the surface of the base material to which the ink is applied, and the non-contact heating means is better than the contact heating means, The ink is a drying mechanism with a high heating temperature, and the ink contains a coloring material, a resin, water, and an organic solvent, and the organic solvent includes at least one organic solvent having a boiling point of 180°C or higher, and the ink has a drying mechanism with a high heating temperature. The content of the organic solvent having a boiling point of 180°C or more is 15% by mass or more, and the ink has a weight loss rate A (unit %) of -95% determined by the following formula (1) in thermogravimetry TG. The measurement time when this occurs is 30 minutes or less, and other means are provided as necessary.

However, in the above formula (1), the "ink loss rate (%) obtained from the measurement results" is the ink weight loss rate obtained as a result of thermogravimetric measurement of the ink. The above-mentioned "saturated weight loss rate (%)" is calculated by calculating the difference in ink weight loss rate every 5 minutes from the measurement results, and the ink weight loss rate (%) during the measurement time when the absolute value of the difference is less than 0.1%. %).

The printing method of the present invention includes an ink applying step of applying ink to a base material, and a drying step of drying the base material to which the ink has been applied, wherein the drying step includes a non-contact heating treatment in which the surface of the substrate to which the ink is applied is heated in a non-contact manner, and a contact heating treatment in which the back side of the surface of the base material to which the ink is applied is heated, and the heating temperature of the contact heating treatment is Therefore, the heating temperature of the non-contact heat treatment is higher, and the ink contains a coloring material, a resin, water, and an organic solvent, and at least an organic solvent having a boiling point of 180° C. or higher is used as the organic solvent. The content of an organic solvent having a boiling point of 180° C. or higher relative to the total amount of the ink is 15% by mass or more, and the ink has a weight loss rate determined by the above formula (1) in thermogravimetry TG. The measurement time when A (unit %) is -95% is 30 minutes or less, and other steps are included as necessary.

The printing method of the present invention can be suitably carried out by the printing apparatus of the present invention, the ink applying step can be performed by an ink applying means, the drying step can be performed by a drying mechanism, and other steps can be performed by other methods. This can be done by the following means.

In the conventional technology, it is difficult to dry substrates that are easily affected by heat, such as plastic films, by simply using a combination of contact heating means such as hot rolls and non-contact heating means such as hot air blowing. In the case of a material, there is a problem that the base material may be thermally deformed or wrinkled.
Furthermore, for example, when a substrate coated with a liquid such as ink is dried with hot air from the surface side of the liquid, the surface side of the liquid dries quickly and some of the solvent remains inside. Occurrence of blocking becomes an issue.

In the present invention, the drying mechanism is a drying mechanism in which the heating temperature of the non-contact heating means is higher than that of the contact heating means, thereby providing excellent drying performance and suppressing thermal deformation of the base material. be able to.
If the heating means that heats the side to which the ink is applied has a higher heating temperature than the heating means that heats the back side of the side to which the ink is applied, drying progresses from the surface of the ink, causing damage to the inside of the ink film. A part of the organic solvent of the ink may remain and cause blocking.
However, in thermogravimetric measurement TG, by using an ink whose measurement time is 30 minutes or less when the weight loss rate A (unit: %) obtained using the above formula (1) is -95%, it is possible to increase the temperature. Even when the ink contains an organic solvent that tends to remain at the boiling point, the organic solvent is easily separated from the ink, and the organic solvent does not remain inside the ink coating, making it possible to suppress the occurrence of blocking.

Calculation of the weight loss rate A (%) in thermogravimetric measurement TG can be performed as follows.
Thermogravimetry TG can be measured using, for example, Rigaku Thermo plus EVO2 TG 8121 (manufactured by Rigaku Co., Ltd.) under the following conditions.
[Measurement condition]
・Temperature program: Set temperature 100℃
・Temperature increase rate: 10℃/min ・Holding time after temperature increase: 70 minutes ・Measurement start temperature: 25℃
・Control thermocouple: Furnace ・Pan: Al (aluminum)
・Sample amount: 10mg±0.3mg

ただし、前記数式（１）中、前記「測定結果から得られるインクの減量率（％）」とは、インクの熱重量測定の結果得られるインクの減量率である。前記「飽和減量率（％）」とは、測定結果から５分ごとのインクの減量率の差分を算出し、前記差分の絶対値が０．１％未満となる測定時間におけるインクの減量率（％）である。
なお、測定時間とは、測定開始温度２５℃から前述の温度プログラムに従って昇温を開始する時を０分とした時の時間である。 The weight loss rate of the ink is measured by placing ink as a sample into the Al pan and measuring it, and the weight loss rate A (%) can be calculated from the measurement results using the following formula (1).

However, in the above formula (1), the "ink loss rate (%) obtained from the measurement results" is the ink weight loss rate obtained as a result of thermogravimetric measurement of the ink. The above-mentioned "saturated weight loss rate (%)" is calculated by calculating the difference in ink weight loss rate every 5 minutes from the measurement results, and the ink weight loss rate (%) during the measurement time when the absolute value of the difference is less than 0.1%. %).
Note that the measurement time is the time when the time at which the temperature starts to increase from the measurement start temperature of 25° C. according to the above-mentioned temperature program is 0 minutes.

For example, the ink loss rate at a measurement time of 60 minutes is called a weight loss rate (60), the ink weight loss rate at a measurement time of 65 minutes is called a weight loss rate (65), and the ink weight loss rate at a measurement time of 70 minutes is called a weight loss rate (70). Then, if the absolute value of weight loss rate (70) - weight loss rate (65) <0.1, and the absolute value of weight loss rate (65) - weight loss rate (60) ≧0.1, weight loss rate (70) is saturated. This is the weight loss rate. Therefore, in this case, if the ink weight loss rate obtained from the measurement result after the measurement time t minutes is the weight loss rate (t), and the weight loss rate A to be calculated is the weight loss rate A(t), the weight loss rate A(t) is It can be calculated using the formula below.
Weight loss rate A (t) (%) = weight loss rate (t) (%) / (saturated weight loss rate (70) (%) / 100)

Hereinafter, the ink used in the printing apparatus and printing method of the present invention, the ink set of the present invention, and the pretreatment liquid and ink set of the present invention will be described in detail.

<Ink>
The ink used in the present invention contains a coloring material, a resin, water, and an organic solvent, and may further contain additives as necessary.

<<Organic solvent>>
The organic solvent includes at least one organic solvent having a boiling point of 180°C or higher, and the content of the organic solvent having a boiling point of 180°C or higher is 15% by mass or more based on the total amount of the ink, and 15% by mass or more based on the total amount of the ink. It is preferably at least 30% by mass. Thereby, the ink can have excellent ejection stability.
The organic solvent having a boiling point of 180° C. or higher is preferably an organic solvent having a boiling point of 180° C. or higher and 250° C. or lower, from the viewpoint of excellent discharge stability and improved drying properties.

Examples of the organic solvent having a boiling point of 180°C or higher include 1,2-propanediol (boiling point 188°C), 1,2-butanediol (boiling point 194°C), ethylene glycol (boiling point 197.3°C), and diethylene glycol. (boiling point 244.3°C), 1,2-propanediol (boiling point 188.2°C), 1,3-butanediol (boiling point 204°C), 1,4-butanediol (boiling point 230°C), 2,3- Butanediol (boiling point 182°C), 3-methyl-1,3-butanediol (boiling point 203°C), triethylene glycol (boiling point 276°C), 1,2-pentanediol (boiling point 206°C), 1,3-pentane Diol (boiling point 209°C), 2,4-pentanediol (boiling point 198°C), 1,5-pentanediol (boiling point 239°C), 1,2-hexanediol (boiling point 223°C), 1,3-hexanediol ( (boiling point 221.7°C), 2,5-hexanediol (boiling point 217°C), glycerin (boiling point 290°C), 2-ethyl-1,3-hexanediol (boiling point 244°C), 1,2,4-butanetriol (boiling point 312°C), 2,2,4-trimethyl-1,3-pentanediol (boiling point 232°C), diethylene glycol monomethyl ether (boiling point 194°C), diethylene glycol monoethyl ether (boiling point 196°C), diethylene glycol monobutyl ether (boiling point 230°C), ethylene glycol monophenyl ether (boiling point 237°C), ethylene glycol monobenzyl ether (boiling point 256°C), 2-pyrrolidone (boiling point 245°C), N-methyl-2-pyrrolidone (boiling point 204°C), γ- Butyrolactone (boiling point 204°C), formamide (boiling point 210°C), N-methylformamide (boiling point 199°C), 3-methoxy-N,N-dimethylpropionamide (boiling point 215.2°C), 3-butoxy-N,N -Dimethylpropionamide (boiling point 215°C), diethanolamine (boiling point 269°C), dimethyl sulfoxide (boiling point 189°C), sulfolane (boiling point 285°C), propylene carbonate (boiling point 240°C), 2-ethyl-1,3-hexanediol (boiling point: 244°C), 2,2,4-trimethyl-1,3-pentanediol (boiling point: 232°C), and the like. These may be used alone or in combination of two or more.

As the organic solvent, an organic solvent other than the organic solvent having a boiling point of 180° C. or higher can also be used.
Such organic solvents are not particularly limited and can be selected as appropriate depending on the purpose; for example, 2,3-butanediol, polyethylene glycol, polypropylene glycol, 1,4-pentanediol, 1,5- Hexanediol, 1,2,6-hexanetriol, 1,2,3-butanetriol, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, tetraethylene glycol monomethyl ether, propylene glycol monopropyl ether, N-hydroxyethyl-2 -Pyrrolidone, 1,3-dimethyl-2-imidazolidinone, ε-caprolactam, N,N-dimethylformamide, monoethanolamine, triethylamine, thiodiethanol, 3-methoxy-3-methyl-1-butanol, etc. . These may be used alone or in combination of two or more.

The content of the organic solvent in the ink (total content when two or more organic solvents are used) is not particularly limited and can be selected as appropriate depending on the purpose, but it may From the viewpoint of reliability, the content is preferably 15% by mass or more and 60% by mass or less, more preferably 20% by mass or more and 60% by mass or less.

＜＜Water＞＞
As the water, pure water such as ion-exchanged water, ultrafiltrated water, reverse osmosis water, distilled water, or ultrapure water can be used.
The water content in the ink is not particularly limited and can be appropriately selected depending on the purpose, but from the viewpoint of ink drying properties and ejection reliability, it is preferably 10% by mass or more and 90% by mass or less, and 20% by mass or less. % or more and 60% by mass or less is more preferable.

＜＜Color material＞＞
The coloring material is not particularly limited, and pigments and dyes can be used.
As pigments, inorganic pigments or organic pigments can be used. These may be used alone or in combination of two or more. Also, mixed crystals may be used.
Examples of pigments that can be used include black pigments, yellow pigments, magenta pigments, cyan pigments, white pigments, green pigments, orange pigments, glossy pigments such as gold and silver, and metallic pigments.
Inorganic pigments include titanium oxide, iron oxide, calcium carbonate, barium sulfate, aluminum hydroxide, barium yellow, cadmium red, and chrome yellow, as well as carbon black produced by known methods such as contact method, furnace method, and thermal method. can be used.
Examples of organic pigments include azo pigments, polycyclic pigments (e.g., phthalocyanine pigments, perylene pigments, perinone pigments, anthraquinone pigments, quinacridone pigments, dioxazine pigments, indigo pigments, thioindigo pigments, isoindolinone pigments, quinofularone pigments, etc.) , dye chelates (eg, basic dye type chelates, acidic dye type chelates, etc.), nitro pigments, nitroso pigments, aniline black, etc. can be used. Among these pigments, those having good affinity with the solvent are preferably used. In addition, resin hollow particles and inorganic hollow particles can also be used.
Specific examples of pigments for black include carbon blacks (C.I. Pigment Black 7) such as furnace black, lamp black, acetylene black, and channel black, or copper and iron (C.I. Pigment Black 11). , metals such as titanium oxide, and organic pigments such as aniline black (C.I. Pigment Black 1).
Furthermore, for color use, C. I. Pigment Yellow 1, 3, 12, 13, 14, 17, 24, 34, 35, 37, 42 (yellow iron oxide), 53, 55, 74, 81, 83, 95, 97, 98, 100, 101, 104 , 108, 109, 110, 117, 120, 138, 150, 153, 155, 180, 185, 213, C. I. Pigment Orange 5, 13, 16, 17, 36, 43, 51, C. I. Pigment Red 1, 2, 3, 5, 17, 22, 23, 31, 38, 48:2 (Permanent Red 2B (Ca)), 48:3, 48:4, 49:1, 52:2, 53: 1, 57:1 (Brilliant Carmine 6B), 60:1, 63:1, 63:2, 64:1, 81, 83, 88, 101 (Red), 104, 105, 106, 108 (Cadmium Red), 112, 114, 122 (quinacridone magenta), 123, 146, 149, 166, 168, 170, 172, 177, 178, 179, 184, 185, 190, 193, 202, 207, 208, 209, 213, 219, 224, 254, 264, C. I. Pigment Violet 1 (Rhodamine Lake), 3, 5:1, 16, 19, 23, 38, C.I. I. Pigment Blue 1, 2, 15 (phthalocyanine blue), 15:1, 15:2, 15:3, 15:4 (phthalocyanine blue), 16, 17:1, 56, 60, 63, C.I. I. Pigment Green 1, 4, 7, 8, 10, 17, 18, 36 and the like.

The dye is not particularly limited, and acid dyes, direct dyes, reactive dyes, and basic dyes can be used, and one type may be used alone or two or more types may be used in combination.
As the dye, for example, C.I. I. Acid Yellow 17, 23, 42, 44, 79, 142, C. I. Acid Red 52, 80, 82, 249, 254, 289, C. I. Acid Blue 9,45,249, C. I. Acid Black 1, 2, 24, 94, C. I. Food black 1, 2, C. I. Direct Yellow 1, 12, 24, 33, 50, 55, 58, 86, 132, 142, 144, 173, C. I. Direct Red 1, 4, 9, 80, 81, 225, 227, C. I. Direct Blue 1, 2, 15, 71, 86, 87, 98, 165, 199, 202, C. I. Directed Black 19, 38, 51, 71, 154, 168, 171, 195, C. I. Reactive Red 14, 32, 55, 79, 249, C. I. Examples include Reactive Black 3, 4, and 35.

The content of the coloring material in the ink is preferably 0.1% by mass or more and 15% by mass or less, more preferably 1% by mass or more and 10% by mass or less, from the viewpoint of improving image density, good fixing properties, and ejection stability. preferable.

To disperse the pigment in the ink, there are two methods: introducing a hydrophilic functional group into the pigment to make it a self-dispersing pigment, coating the surface of the pigment with a resin and dispersing it, dispersing it using a dispersant, Examples include.
Examples of methods for creating self-dispersing pigments by introducing hydrophilic functional groups into pigments include self-dispersing pigments in which functional groups such as sulfone groups and carboxyl groups are added to pigments (e.g., carbon) to make them dispersible in water. Pigments etc. can be used.
As a method for coating the surface of a pigment with a resin and dispersing it, a method can be used in which the pigment is encapsulated in microcapsules and can be dispersed in water. This can be referred to as a resin-coated pigment. In this case, all the pigments blended into the ink do not need to be coated with the resin, and uncoated pigments or partially coated pigments may be dispersed in the ink as long as the effects of the present invention are not impaired. You can leave it there.
Examples of the method for dispersing using a dispersant include methods for dispersing using known low-molecular-type dispersants and polymer-type dispersants, typified by surfactants.
As the dispersant, it is possible to use, for example, an anionic surfactant, a cationic surfactant, an amphoteric surfactant, a nonionic surfactant, etc. depending on the pigment.
RT-100 (nonionic surfactant) manufactured by Takemoto Yushi Co., Ltd. and formalin condensate of naphthalene sulfonate can also be suitably used as the dispersant.
One type of dispersant may be used alone, or two or more types may be used in combination.

<<Pigment dispersion>>
Ink can be obtained by mixing materials such as water and organic solvents with coloring materials. It is also possible to manufacture ink by mixing a pigment with other materials such as water and a dispersant to form a pigment dispersion, and then mixing materials such as water and an organic solvent.
The pigment dispersion is obtained by dispersing water, a pigment, a pigment dispersant, and other components as necessary, and adjusting the particle size. For dispersion, it is preferable to use a disperser.
There is no particular restriction on the particle size of the pigment in the pigment dispersion, but the maximum frequency in terms of the maximum number of particles is 20 nm or more, since the dispersion stability of the pigment is good and the image quality such as ejection stability and image density is also high. The thickness is preferably 500 nm or less, more preferably 20 nm or more and 150 nm or less. The particle size of the pigment can be measured using a particle size analyzer (Nanotrac Wave-UT151, manufactured by Microtrac Bell Co., Ltd.).
The pigment content in the pigment dispersion is not particularly limited and can be appropriately selected depending on the purpose, but from the viewpoint of obtaining good ejection stability and increasing image density, 0.1 mass % or more and 50% by mass or less, more preferably 0.1% by mass or more and 30% by mass or less.
It is preferable that the pigment dispersion is filtered to remove coarse particles using a filter, centrifugal separator, etc. and degassed, if necessary.

<<Resin>>
The type of resin contained in the ink can be selected as appropriate depending on the purpose; for example, urethane resin, polyester resin, acrylic resin, vinyl acetate resin, styrene resin, butadiene resin, styrene-butadiene. Examples include acrylic resins, vinyl chloride resins, acrylic-styrene resins, and acrylic-silicone resins.
Resin particles made of these resins may also be used. It is possible to obtain ink by mixing resin particles with materials such as colorants and organic solvents in the state of a resin emulsion in which resin particles are dispersed using water as a dispersion medium. The resin particles may be appropriately synthesized or commercially available. These resins may be used alone or in combination of two or more.
In one aspect of the present invention, the ink includes an acrylic resin as a resin, the acrylic resin has styrene and a structure represented by the following general formula (1), and the styrene and the general formula (1) It is preferable that the ratio to the structure represented by [Structure represented by general formula (1)/(Structure represented by general formula (1) + styrene)] is 0.45 or more and 0.9 or less. As a result, it is possible to obtain an ink that is excellent in releasing the solvent during heating, and furthermore, it is possible to form an image that is excellent in scratch resistance.

ただし、前記一般式（１）中、Ｒはアルキル基を表す。
前記アルキル基としては、直鎖又は分岐鎖、或いは環状の炭素数１以上２０以下のアルキル基が好ましく、炭素数１以上１０以下のアルキル基がより好ましい。
前記アルキル基としては、メチル基、エチル基、プロピル基、ブチル基、イソプロピル基、イソブチル基、ペンチル基、ヘキシル基、ヘプチル基、エチルヘキシル基、オクチル基、デシル基、ドデシル基、２－ブチルオクチル基、オクタデシル基、シクロプロピル基、シクロブチル基、シクロペンチル基、シクロヘキシル基、アダマンチル基などが挙げられる。

However, in the general formula (1), R represents an alkyl group.
The alkyl group is preferably a linear, branched, or cyclic alkyl group having 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms.
Examples of the alkyl group include methyl group, ethyl group, propyl group, butyl group, isopropyl group, isobutyl group, pentyl group, hexyl group, heptyl group, ethylhexyl group, octyl group, decyl group, dodecyl group, and 2-butyloctyl group. , octadecyl group, cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, adamantyl group, etc.

The volume average particle diameter of the resin particles is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 10 nm or more and 1,000 nm or less, more preferably 10 nm or more and 200 nm or less, and particularly 50 nm or more and 150 nm or less. preferable.
The volume average particle diameter can be measured, for example, using a particle size analyzer (Nanotrac Wave-UT151, manufactured by Microtrac Bell Co., Ltd.).

The glass transition temperature of the resin is preferably 30°C or more and 100°C or less, more preferably 40°C or more and 80°C or less. Thereby, it is possible to form an image that is further excellent in blocking prevention, scratch resistance, and the like.

The content of the resin is not particularly limited and can be selected as appropriate depending on the purpose, but from the viewpoint of fixing properties and storage stability of the ink, it is 1% by mass or more and 30% by mass based on the total amount of ink. % or less, more preferably 5% by mass or more and 20% by mass or less.

<<Additives>>
Additives such as a surfactant, an antifoaming agent, a preservative and fungicide, a rust preventive, and a pH adjuster may be added to the ink as necessary.

-Surfactant-
As the surfactant, any of silicone surfactants, fluorine surfactants, amphoteric surfactants, nonionic surfactants, and anionic surfactants can be used.
The silicone surfactant is not particularly limited and can be appropriately selected depending on the purpose. Among these, those that do not decompose even at high pH are preferable, such as side chain-modified polydimethylsiloxane, both-terminally modified polydimethylsiloxane, single-end-modified polydimethylsiloxane, and both side-chain-terminated polydimethylsiloxanes. Particularly preferred are those having a polyoxyethylene group or a polyoxyethylene polyoxypropylene group, as they exhibit good properties as a water-based surfactant. Further, as the silicone surfactant, a polyether-modified silicone surfactant can also be used, such as a compound in which a polyalkylene oxide structure is introduced into the side chain of the Si part of dimethylsiloxane.

Examples of fluorine-based surfactants include perfluoroalkyl sulfonic acid compounds, perfluoroalkyl carboxylic acid compounds, perfluoroalkyl phosphate ester compounds, perfluoroalkyl ethylene oxide adducts, and perfluoroalkyl ether groups in their side chains. Polyoxyalkylene ether polymer compounds are particularly preferred because they have low foaming properties. Examples of the perfluoroalkylsulfonic acid compound include perfluoroalkylsulfonic acid, perfluoroalkylsulfonic acid salts, and the like. Examples of the perfluoroalkylcarboxylic acid compound include perfluoroalkylcarboxylic acids, perfluoroalkylcarboxylic acid salts, and the like. The polyoxyalkylene ether polymer compound having a perfluoroalkyl ether group in its side chain includes a sulfate ester salt of a polyoxyalkylene ether polymer having a perfluoroalkyl ether group in its side chain, and a sulfate salt of a polyoxyalkylene ether polymer having a perfluoroalkyl ether group in its side chain. Examples include salts of polyoxyalkylene ether polymers. Counter ions of the salts in these fluorosurfactants include Li, Na, K, NH ₄ , NH ₃ CH ₂ CH ₂ OH, NH ₂ (CH ₂ CH ₂ OH) ₂ , NH (CH ₂ CH ₂ OH) Examples include ₃ .

Examples of the amphoteric surfactant include lauryl aminopropionate, lauryl dimethyl betaine, stearyl dimethyl betaine, lauryl dihydroxyethyl betaine, and the like.
Examples of nonionic surfactants include polyoxyethylene alkylphenyl ether, polyoxyethylene alkyl ester, polyoxyethylene alkylamine, polyoxyethylene alkylamide, polyoxyethylene propylene block polymer, sorbitan fatty acid ester, polyoxyethylene sorbitan Examples include fatty acid esters and ethylene oxide adducts of acetylene alcohol.
Examples of the anionic surfactant include polyoxyethylene alkyl ether acetate, dodecylbenzene sulfonate, laurate, polyoxyethylene alkyl ether sulfate salt, and the like.
These may be used alone or in combination of two or more.

The silicone surfactant is not particularly limited and can be appropriately selected depending on the purpose, but examples include side chain-modified polydimethylsiloxane, double-end modified polydimethylsiloxane, single-end modified polydimethylsiloxane, side-chain-modified polydimethylsiloxane, Examples include polydimethylsiloxane modified at both chain ends, and polyether-modified silicone surfactants having polyoxyethylene groups and polyoxyethylene polyoxypropylene groups as modifying groups exhibit good properties as water-based surfactants, so they are particularly useful. preferable.
Such surfactants may be appropriately synthesized or commercially available. Commercially available products are available from, for example, BIC Chemie Co., Ltd., Shin-Etsu Chemical Co., Ltd., Dow Corning Toray Silicone Co., Ltd., Nippon Emulsion Co., Ltd., Kyoeisha Chemical Co., Ltd., etc.

The above-mentioned polyether-modified silicone surfactant is not particularly limited and can be selected as appropriate depending on the purpose. Examples include those introduced into the side chain of the Si portion of polysiloxane.

(However, in the general formula (S-1), m, n, a, and b each independently represent an integer, R represents an alkylene group, and R' represents an alkyl group.)

Commercially available products can be used as the polyether-modified silicone surfactant, such as KF-618, KF-642, KF-643 (manufactured by Shin-Etsu Chemical Co., Ltd.), EMALEX-SS-5602, SS- 1906EX (manufactured by Nippon Emulsion Co., Ltd.), FZ-2105, FZ-2118, FZ-2154, FZ-2161, FZ-2162, FZ-2163, FZ-2164 (manufactured by Toray Dow Corning Silicone Co., Ltd.), BYK- 33, BYK-387 (manufactured by BYK Chemie Corporation), TSF4440, TSF4452, TSF4453 (manufactured by Toshiba Silicon Corporation), and the like.

The fluorine-based surfactant is preferably a fluorine-substituted compound having 2 to 16 carbon atoms, more preferably a fluorine-substituted compound having 4 to 16 carbon atoms.
Examples of the fluorosurfactant include perfluoroalkyl phosphate compounds, perfluoroalkyl ethylene oxide adducts, and polyoxyalkylene ether polymer compounds having perfluoroalkyl ether groups in their side chains.
Among these, polyoxyalkylene ether polymer compounds having a perfluoroalkyl ether group in the side chain are preferred because of their low foaming properties, and are represented by the following general formula (F-1) and the following general formula (F-2). Fluorine surfactants are particularly preferred.

[General formula (F-1)]
In the compound represented by the above general formula (F-1), m is preferably an integer of 0 to 10, and n is preferably an integer of 0 to 40, in order to impart water solubility.

[General formula (F-2)]
C _n F _2n+1- CH ₂ CH(OH)CH ₂ -O-(CH ₂ CH ₂ O) _a -Y
In the compound represented by the above general formula (F-2), Y is H, or C _n F _2n+1 , and n is an integer of 1 to 6, or CH ₂ CH(OH)CH ₂ -C _n F _2n+1. , n is an integer from 4 to 6, and in C _p H _2p+1 , p is an integer from 1 to 19. a is an integer from 4 to 14.

Commercially available products may be used as the fluorosurfactant.
Examples of the commercially available products include Surflon S-111, S-112, S-113, S-121, S-131, S-132, S-141, and S-145 (all manufactured by Asahi Glass Co., Ltd.); Fullard FC-93, FC-95, FC-98, FC-129, FC-135, FC-170C, FC-430, FC-431 (all manufactured by Sumitomo 3M Ltd.); Megafac F-470, F -1405, F-474 (all manufactured by DIC Corporation); Zonyl TBS, FSP, FSA, FSN-100, FSN, FSO-100, FSO, FS-300, UR, Capstone FS-30, FS-31, FS-3100, FS-34, FS-35 (all manufactured by Chemours); FT-110, FT-250, FT-251, FT-400S, FT-150, FT-400SW (all manufactured by Chemours) Polyfox PF-136A, PF-156A, PF-151N, PF-154, PF-159 (manufactured by Omnova), and Unidyne DSN-403N (manufactured by Daikin Industries, Ltd.). Among these, FS-3100, FS-34, FS-300 manufactured by Chemours, and Neos Co., Ltd. are recommended because they have good print quality, especially color development, paper permeability, wettability, and level dyeing. Particularly preferred are FT-110, FT-250, FT-251, FT-400S, FT-150, FT-400SW manufactured by Omnova, Polyfox PF-151N manufactured by Omnova, and Unidyne DSN-403N manufactured by Daikin Industries, Ltd.

The content of the surfactant in the ink is not particularly limited and can be selected as appropriate depending on the purpose, but from the viewpoint of excellent wettability, ejection stability, and improved image quality, 0.001 mass % or more and 5% by mass or less, more preferably 0.05% or more and 5% by mass or less.

-Defoaming agent-
The antifoaming agent is not particularly limited and includes, for example, silicone antifoaming agents, polyether antifoaming agents, fatty acid ester antifoaming agents, and the like. These may be used alone or in combination of two or more. Among these, silicone antifoaming agents are preferred because they have excellent foam-breaking effects.

-Preservative and fungicide-
The preservative and fungicide is not particularly limited and includes, for example, 1,2-benzisothiazolin-3-one.

-anti-rust-
There are no particular limitations on the rust preventive, and examples thereof include acidic sulfites, sodium thiosulfate, and the like.

-pH adjuster-
The pH adjuster is not particularly limited as long as it can adjust the pH to 7 or more, and examples thereof include amines such as diethanolamine and triethanolamine.

The ink used in the present invention must be measured in thermogravimetry TG for a measurement time of 30 minutes or less when the weight loss rate A (unit: %) determined by the above formula (1) is -95%. In addition, the physical properties of the ink are not particularly limited and can be appropriately selected depending on the purpose. For example, the viscosity, surface tension, pH, etc. are preferably within the following ranges.
The viscosity of the ink at 25°C is preferably 5 mPa·s or more and 30 mPa·s or less, and 5 mPa·s or more and 25 mPa·s or less, from the viewpoint of improving print density and character quality and obtaining good ejection properties. More preferred. Here, the viscosity can be measured using, for example, a rotational viscometer (manufactured by Toki Sangyo Co., Ltd., RE-80L). The viscosity can be measured at 25° C., using a standard cone rotor (1° 34′ x R24), sample liquid volume 1.2 mL, rotation speed 50 rpm, and 3 minutes.
The surface tension of the ink is preferably 35 mN/m or less, more preferably 32 mN/m or less at 25° C., from the viewpoint of suitably leveling the ink on the recording medium and forming an image.
The pH of the ink is preferably 7 to 12, more preferably 8 to 11, from the viewpoint of preventing corrosion of metal members in contact with the ink.

The coloring of the ink of the present invention is not particularly limited and can be appropriately selected depending on the purpose, such as yellow, magenta, cyan, black, or white.

ただし、前記数式（１）中、前記「測定結果から得られるインクの減量率（％）」とは、インクの熱重量測定の結果得られるインクの減量率である。前記「飽和減量率（％）」とは、測定結果から５分ごとのインクの減量率の差分を算出し、前記差分の絶対値が０．１％未満となる測定時間におけるインクの減量率（％）である。 (ink set)
The ink set of the present invention is an ink set consisting of at least two types selected from cyan ink, magenta ink, yellow ink, black ink, and white ink,
At least two types of ink selected from the cyan ink, magenta ink, yellow ink, black ink, and white ink each contain a coloring material, a resin, water, and an organic solvent,
The organic solvent includes at least one organic solvent having a boiling point of 180° C. or higher, and the content of the organic solvent having a boiling point of 180° C. or higher based on the total amount of the ink is 15% by mass or higher,
In the thermogravimetric measurement TG, the measurement time when the weight loss rate A (unit %) determined by the following formula (1) is -95% is 30 minutes or less.

However, in the above formula (1), the "ink loss rate (%) obtained from the measurement results" is the ink weight loss rate obtained as a result of thermogravimetric measurement of the ink. The above-mentioned "saturated weight loss rate (%)" is calculated by calculating the difference in ink weight loss rate every 5 minutes from the measurement results, and the ink weight loss rate (%) during the measurement time when the absolute value of the difference is less than 0.1%. %).

When recording is performed using an ink set in which two or more types are used in combination, a multicolor image can be recorded, and when recording is performed using an ink set in which all colors are used in combination, a full color image can be recorded. White ink is suitable as a base for color images.

<Base material>
The base material is not particularly limited, and plain paper, glossy paper, special paper, cloth, etc. can be used, but good image formation is possible even when a non-permeable base material is used.
The non-permeable base material is a base material that has a surface with low absorbency, and includes materials that have many cavities inside but are not open to the outside.More quantitatively, Bristow ) refers to a base material whose water absorption amount from the start of contact to 30 msec ^1/2 is 10 mL/m ² or less.
As the impermeable base material, for example, polyester films such as polyvinyl chloride resin films and polyethylene terephthalate (PET) films, plastic films such as polypropylene films, stretched polypropylene films, polyethylene films, and polycarbonate films are suitably used. be able to.
The base material preferably has an average thickness of 30 μm or less and is a stretched polypropylene film or a polyester film.

The base material is not limited to those used as general recording media, and may be appropriately used such as wallpaper, flooring materials, building materials such as tiles, cloth for clothing such as T-shirts, textiles, leather, and the like. Further, by adjusting the configuration of the route for conveying the base material, ceramics, glass, metal, etc. can also be used.

In one aspect of the present invention, it is preferable that a pretreatment liquid application mechanism is provided for applying a pretreatment liquid to the substrate before applying ink to the substrate, and the pretreatment liquid contains a resin. By applying the pretreatment liquid, a higher quality image can be formed.

<Pre-treatment liquid>
The pretreatment liquid used in the present invention preferably contains a resin, more preferably contains a flocculant, an organic solvent, and water, and optionally contains a surfactant, an antifoaming agent, a pH adjuster, It may contain additives such as a preservative, a fungicide, and a rust preventive agent.

The method for applying the pretreatment liquid is not particularly limited and can be appropriately selected depending on the purpose, such as inkjet method, blade coating method, gravure coating method, gravure offset coating method, bar coating method, roll coating. method, knife coating method, air knife coating method, comma coating method, U comma coating method, AKKU coating method, smoothing coating method, microgravure coating method, reverse roll coating method, 4 roll coating method, 5 roll coating method, dip Examples include a coating method, a curtain coating method, a slide coating method, and a die coating method.

-resin-
The type of resin contained in the pretreatment liquid is not particularly limited and can be appropriately selected depending on the purpose. For example, urethane resin, polyester resin, acrylic resin, vinyl acetate resin, styrene resin. , butadiene resin, styrene-butadiene resin, vinyl chloride resin, acrylic-styrene resin, acrylic-silicone resin, etc.
Resin particles made of these resins may also be used. It is possible to obtain a pretreatment liquid by mixing resin particles with other materials in the state of a resin emulsion in which resin particles are dispersed using water as a dispersion medium. The resin particles may be appropriately synthesized or commercially available. Moreover, these resins may be used alone or in combination of two or more types.

The content of the resin in the pretreatment liquid is preferably 1% by mass or more and 35% by mass or less, more preferably 5% by mass or more and 20% by mass or less.

-Flocculant-
The type of flocculant is not particularly limited and can be appropriately selected depending on the purpose, and examples thereof include water-soluble cationic polymers, acids, metal salts, and the like.
When using a metal salt, it is preferably a polyvalent metal salt.
Examples of metal salts include titanium salts, chromium salts, copper salts, cobalt salts, strontium salts, barium salts, iron salts, aluminum salts, calcium salts, potassium salts, sodium salts, nickel salts, and magnesium salts.

By using an aggregating agent, the aggregating agent reacts with components in the ink to suppress blurring of an image, and a high-quality image can be formed.

Regarding the organic solvent, the surfactant, the antifoaming agent, the pH adjuster, the preservative and fungicide, and the rust preventive agent in the pretreatment liquid, the same materials as those for the ink can be used, and in addition, Materials used in known processing liquids can be used.

ただし、前記数式（１）中、前記「測定結果から得られるインクの減量率（％）」とは、インクの熱重量測定の結果得られるインクの減量率である。前記「飽和減量率（％）」とは、測定結果から５分ごとのインクの減量率の差分を算出し、前記差分の絶対値が０．１％未満となる測定時間におけるインクの減量率（％）である。 (Set of pre-treatment liquid and ink)
The pretreatment liquid and ink set of the present invention includes a pretreatment liquid containing a resin,
A pretreatment liquid and ink set comprising at least one selected from cyan ink, magenta ink, yellow ink, black ink, and white ink,
At least one type of ink selected from the cyan ink, magenta ink, yellow ink, black ink, and white ink each contains a coloring material, a resin, water, and an organic solvent,
The organic solvent includes at least one organic solvent having a boiling point of 180° C. or higher, and the content of the organic solvent having a boiling point of 180° C. or higher based on the total amount of the ink is 15% by mass or higher,
In the thermogravimetric measurement TG, the measurement time when the weight loss rate A (unit %) determined by the following formula (1) is -95% is 30 minutes or less.

However, in the above formula (1), the "ink loss rate (%) obtained from the measurement results" is the ink weight loss rate obtained as a result of thermogravimetric measurement of the ink. The above-mentioned "saturated weight loss rate (%)" is calculated by calculating the difference in ink weight loss rate every 5 minutes from the measurement results, and the ink weight loss rate (%) during the measurement time when the absolute value of the difference is less than 0.1%. %).

<Printing device and printing method>
Next, embodiments for implementing the printing apparatus and printing method of the present invention will be described with reference to the drawings. In each drawing, the same components are given the same reference numerals, and redundant explanations may be omitted.

In the terms of the embodiment, image formation, recording, printing, imprinting, printing, modeling, etc. are all synonymous.

In this embodiment, the "device for ejecting liquid" is a device that includes a liquid ejection head or a liquid ejection unit and drives the liquid ejection head to eject liquid. Note that "device for discharging liquid" and "liquid discharging device" have the same meaning.

The "device for discharging liquid" may include means for feeding, transporting, and discharging objects to which liquid can adhere, as well as pre-processing devices, post-processing devices, and the like.

For example, "devices that eject liquid" include printing devices, image forming devices, inkjet recording devices, and the like, which are devices that eject liquid such as ink to form an image on a base material.

The above-mentioned "something to which a liquid can adhere" means something to which a liquid can adhere at least temporarily, such as something that adheres and sticks, something that adheres and penetrates, etc.

The "liquid" is not particularly limited as long as it has a viscosity or surface tension that allows it to be discharged from the head, but it must be one that has a viscosity of 30 mPa・s or less at room temperature and pressure, or when heated or cooled. Preferably, there is an ink, and examples thereof include ink.

A "liquid ejection unit" is a liquid ejection head with functional parts and mechanisms integrated, and is an assembly of parts related to liquid ejection. For example, the "liquid ejection unit" includes a combination of a liquid ejection head and at least one of the following structures: a head tank, a carriage, a supply mechanism, a maintenance recovery mechanism, and a main scanning movement mechanism.

Here, integration refers to, for example, a liquid ejection head, a functional component, or a mechanism fixed to each other by fastening, adhesion, engagement, etc., or one in which one is held movably relative to the other. include. Further, the liquid ejection head, the functional parts, and the mechanism may be configured to be detachable from each other.

For example, some liquid ejection units have a liquid ejection head and a head tank integrated. In addition, there are devices in which a liquid ejection head and a head tank are integrated by being connected to each other with a tube or the like. Here, a unit including a filter may be added between the head tank and the liquid ejection head of these liquid ejection units.

Further, some liquid ejection units have a liquid ejection head and a carriage integrated.

Further, some liquid ejection units have the liquid ejection head movably held by a guide member that constitutes a part of the scanning movement mechanism, so that the liquid ejection head and the scanning movement mechanism are integrated. Further, there are some in which the liquid ejection head, the carriage, and the main scanning movement mechanism are integrated.

Furthermore, some liquid ejection units have a cap member, which is part of the maintenance recovery mechanism, fixed to the carriage to which the liquid ejection head is attached, so that the liquid ejection head, the carriage, and the maintenance recovery mechanism are integrated. .

Further, some liquid ejection units have a tube connected to a liquid ejection head to which a head tank or a flow path component is attached, so that the liquid ejection head and a supply mechanism are integrated. The liquid from the liquid storage source is supplied to the liquid ejection head through this tube.

The main scanning movement mechanism also includes a single guide member. Further, the supply mechanism includes a single tube and a single loading section.

A "liquid ejection head" is a functional component that ejects and jets liquid from a nozzle.

Piezoelectric actuators (laminated piezoelectric elements and thin-film piezoelectric elements), thermal actuators using electrothermal conversion elements such as heating resistors, and electrostatic actuators consisting of a diaphragm and opposing electrodes are used as energy sources for discharging liquid. Includes things that do.

[First embodiment]
The first embodiment will be described below, taking as an example a case where a "substrate to which a liquid can adhere" is used as a base material and an "device for ejecting a liquid" is an inkjet type image forming apparatus. Note that the base material is a thin film made of plastic such as polypropylene or polyethylene terephthalate, which is used in food packaging applications.

First, FIG. 1 is a diagram illustrating an example of the configuration of an image forming apparatus according to the present embodiment. The image forming apparatus 100 includes a liquid ejection unit 1 , a drying unit 2 , a supply unit 3 , a discharge unit 4 , and a transport unit 5 . The image forming apparatus 100 transports the base material 20 supplied from the supply unit 3 by the transport unit 5 along a transport direction 10 indicated by an arrow. The image forming apparatus 100 also discharges ink onto the substrate 20 that is being conveyed, causes the ink to adhere to the surface of the substrate 20, and forms an image.

Here, the base material 20 is a roll-shaped continuous film that can be wound up.

The liquid ejected from the liquid ejection unit 1 is, for example, the above-mentioned ink.

The liquid ejection unit 1 includes a black liquid ejection head 1K, a yellow liquid ejection head 1Y, a cyan liquid ejection head 1C, and a magenta liquid ejection head 1M. Each of the liquid ejection heads 1K to 1M ejects four colors of liquid: black (K), yellow (Y), cyan (C), and magenta (M).

However, in this embodiment, an image forming apparatus having four color liquid ejection heads of black (K), cyan (C), magenta (M), and yellow (Y) will be described, but the present invention is not limited thereto. For example, it may further include a liquid ejection head corresponding to green (G), red (R), violet (V), light cyan (LC), light magenta (LM), white (W), metallic, and/or other colors. good.

The supply unit 3 holds the base material 20 before liquid is discharged, and supplies the base material 20. The base material 20 is supplied from the supply unit 3 as image formation by the liquid ejection unit 1 and drying by the drying unit 2 progress. The supply unit 3 includes, for example, a supply roller around which the base material 20 is wound, a motor that rotates the supply roller, and a control unit that controls the motor.

The drying unit 2 dries the liquid discharged onto the base material 20. This drying unit 2 will be described in detail separately.

The discharge unit 4 winds up the dried base material 20. The discharge unit 4 includes, for example, a discharge roller around which the base material 20 is wound, a motor that rotates the discharge roller, and a control unit that controls the motor.

The transport unit 5 transports the base material 20 supplied from the supply unit 3 toward the liquid discharge unit 1, the drying unit 2, the discharge unit 4, and the like. The conveyance unit 5 includes, for example, a plurality of conveyance rollers including a drive roller and a driven roller, a motor that rotates the drive roller, a control unit that controls the motor, and a belt member wound around the conveyance roller. ing.

Next, an example of the hardware configuration of the control device 200 included in the image forming apparatus of this embodiment will be described with reference to the block diagram of FIG. 2.

As shown in FIG. 2, the control device 200 includes a CPU (Central Processing Unit) 201, a RAM (Random Access Memory) 202, a ROM (Read Only Memory) 203, and an external I/F (Interface) 204. and HDD (Hard Disk Drive) 205.
The control device 200 also includes a hot air temperature sensor I/F 206, a non-contact heater I/F 207, a drum sensor I/F 208, and a drum heater I/F 209. These are interconnected via a system bus 220.

CPU 201 centrally controls the operation of control device 200 . The CPU 201 executes programs stored in the ROM 203, HDD 205, etc., using the RAM 202 as a work area. This controls the overall operation of the control device 200 and realizes various functions described below. The external I/F 204 is an interface for connecting the image forming apparatus 100 with external devices such as a PC (Personal Computer) and a motor control unit, and an external network.

The control device 200 controls the hot air temperature sensor 210, the non-contact heater 211, and the drum via the hot air temperature sensor I/F 206, non-contact heater I/F 207, drum sensor I/F 208, and drum heater I/F 209, respectively. It is connected to a temperature sensor 212 and a drum heater 213. This makes it possible to send and receive data or signals to and from each of these devices.

The hot air temperature sensor 210 detects the temperature of the hot air blown from the non-contact heater 211 and feeds it back to the control device 200 via the hot air temperature sensor I/F 206. Further, the drum temperature sensor 212 detects the temperature of the drum heater 213 and feeds it back to the control device 200 via the drum temperature sensor I/F 208. The hot air temperature sensor 210 and the drum temperature sensor 212 are, for example, non-contact radiation thermometers.

Note that part or all of the processing performed by the CPU 201 may be realized by an electronic circuit such as an FPGA (Field-Programmable Gate Array) or an ASIC (Application Specific Integrated Circuit).

Further, a configuration may be adopted in which the control device 200 realizes the functions of the motor control units of the supply unit 3, the discharge unit 4, and the transport unit 5.

The control device 200 can realize the functional configuration described below using instructions from the CPU 201 and the hardware configuration shown in FIG.

FIG. 3 is a block diagram showing an example of the functional configuration of the control device 200 included in the image forming apparatus of this embodiment. The control device 200 includes a first setting section 301 , a drum temperature detection section 302 , a second setting section 303 , and a hot air temperature detection section 304 . The first setting section 301 is connected to the drum heater 213 and sets the temperature of the drum heater 213. The temperature of the drum heater 213 is detected by the drum temperature sensor 212 and fed back to the first setting section 301 via the drum temperature detection section 302.

Further, the second setting unit 303 is connected to the non-contact heater 211 and sets the heating temperature by the non-contact heater 211. Heating by the non-contact heater 211 is performed, for example, by blowing heated air, that is, warm air. The temperature of the hot air is detected by the hot air temperature sensor 210 and fed back to the second setting unit 303 via the hot air temperature detection unit 304.

The first setting unit 301 is realized, for example, by the CPU 201 reading temperature data stored in the HDD 205 or the like and setting the temperature of the drum heater 213 via the drum heater I/F 209. Alternatively, this can be achieved by the CPU 201 setting the temperature of the drum heater 213 via the drum heater I/F 209 based on temperature data from the drum temperature detection unit 302 . The drum temperature detection unit 302 is realized by, for example, a drum temperature sensor I/F 208 or the like.

On the other hand, the second setting unit 303 is realized, for example, by the CPU 201 reading temperature data stored in the HDD 205 or the like and setting the heating temperature of the non-contact heater 211 via the non-contact heater I/F 207. Alternatively, this can be realized by the CPU 201 setting the heating temperature of the non-contact heater 211 via the non-contact heater I/F 207 based on temperature data from the hot air temperature detection unit 304 . The hot air temperature detection unit 304 is realized by, for example, a hot air temperature sensor I/F 206 or the like.

The above is an overall outline of the image forming apparatus 100 of this embodiment, and the drying unit 2 included in the image forming apparatus 100 of this embodiment will be described in detail below.

FIG. 4 shows an example of the configuration of the drying unit 2 included in the image forming apparatus 100 of this embodiment. The drying unit 2 includes a non-contact heater 211 and a drum heater 213. The drying unit 2 also includes a conveyance roller 5a that is part of the conveyance unit 5.

The drum heater 213 is a rotatable cylindrical member with a built-in heater. The solid black arrow shown in FIG. 4 indicates the rotation direction of the drum heater 213. The base material 20 is conveyed in the direction of the conveyance direction 10 shown by the white arrow so as to be wrapped around the drum heater 213 . The drum heater 213 is in contact with the back side of the surface of the base material 20 on which the liquid is discharged, that is, the back surface.

The drum heater 213 dries the liquid discharged onto the base material 20 by transferring heat to the back surface of the base material 20 being transported. If it comes into contact with an undried liquid due to drying, the liquid may be disturbed and the image may be distorted. However, the heat transfer by the drum heater 213 is performed from the back side of the base material 20, Do not come into contact with liquid. Therefore, such liquid disturbance and image disturbance are not caused.

On the other hand, the non-contact heater 211 has a plurality of nozzles, and blows heated air at a predetermined speed through each nozzle, that is, warm air, to the surface of the base material 20 on which the liquid is discharged, that is, the front surface. The non-contact heater 211 dries the undried liquid on the front surface of the base material 20 with hot air in a non-contact manner.

Since the non-contact heater 211 performs heating in a non-contact manner, it is possible to dry the liquid discharged onto the base material 20 without causing any disturbance of the liquid or disturbance of the image due to contact as described above.

Note that the front surface is an example of "the surface of the substrate to be transported, on which the liquid is discharged." The non-contact heater 211 is a typical example of a "non-contact heating means that heats the surface of the recording medium on which the liquid has been discharged without contact", and the drum heater 213 is a typical example of a "non-contact heating means that heats the surface of the recording medium on which the liquid has been ejected". This is a typical example of "contact heating means that contacts the back side of the discharge surface." Further, the drum heater 213 is a typical example of "a cylindrical member around which a base material is wound."

FIG. 5 is an enlarged view of the nozzle portion of the non-contact heater 211 in the drying unit 2. As shown in FIG.

As shown in FIG. 5, the liquid 40 discharged by the liquid discharge unit 1 is attached to the front surface 20a of the base material 20 that is conveyed along the conveyance direction 10. Nozzles 211a and 211b of the non-contact heater 211 are arranged to face the front surface 20a of the base material 20. Note that the nozzles 211a and 211b are some of the plurality of nozzles that the non-contact heater 211 has. The non-contact heater 211 blows hot air 41 onto the front surface 20a of the base material 20 through nozzles 211a and 211b.

A hot air temperature sensor 210 is arranged at the blow-off portion at the tip of the nozzle 211a and 211b so as to be exposed to the hot air from the nozzle 211a and 211b. The hot air temperature sensor 210 detects the temperature of the hot air produced by the nozzles 211a and 211b, and feeds it back to the control device 200.

Note that the distance between the nozzles 211a and 211b and the front surface 20a of the base material 20 is, for example, 10 mm. Further, the hot air temperature sensor 210 may detect the temperature of hot air from all nozzles included in the non-contact heater 211, or may detect the temperature of hot air from some nozzles.

On the other hand, the back surface 20b of the base material 20 contacts the drum heater 213 as described above, and heat is transferred by the drum heater 213.

FIG. 6 is a perspective view showing an example of a configuration for detecting the temperature of the drum heater 213. As shown in FIG. 6, the drum temperature sensor 212 is arranged to detect the temperature of a portion of the drum heater 213 that is not in contact with the base material 20. The drum temperature sensor 212 detects the temperature of the drum heater 213 and feeds it back to the control device 200.

Note that the position where the drum temperature sensor 212 is placed is not limited to the example shown in FIG. 6, but it is preferably placed so as to detect the temperature of the portion of the cylindrical surface of the drum heater 213 where the base material 20 is not wrapped. . For example, this is because temperature can be detected regardless of the presence or absence of the base material 20. The drum temperature sensor 212 is an example of a "temperature sensor that detects the temperature of a portion of the cylindrical surface of a cylindrical member where the base material is not wrapped."

Here, the drying characteristics of the base material will be explained. In order to dry the liquid 40 attached to the base material 20, it is necessary to evaporate the water and solvent contained in the liquid 40. In this embodiment, drying is accelerated by heating using the drying unit 2.

A plastic film as a base material is more susceptible to heat than paper or the like, and may be deformed by heating to, for example, about 100° C., depending on the type.

FIG. 7 shows the amount of deformation, that is, the elongation, of the base material when the base material is heated while applying the necessary tension for conveyance. The horizontal axis in FIG. 7 is the heating temperature, and the vertical axis is the elongation of the base material. The elongation of the base material is expressed as a percentage of elongation from the original length. A black circle mark 71 is for a base material made of PET (Poly-Ethylene Terephthalate), and a white circle mark 72 is for a base material made of OPP. Hereinafter, a base material made of PET will be referred to as a PET film, and a base material made of OPP will be referred to as an OPP film.

As shown in FIG. 7, the OPP film rapidly elongates at temperatures exceeding 80°C. The elongation of OPP film at 100° C. of 1% is an elongation that can be visually confirmed. Furthermore, wrinkles occur in the base material due to non-uniform elongation at different locations on the base material. Therefore, if the elongation exceeds 1%, it may be difficult to use it in practical applications such as food packaging.

In this embodiment, it is preferable that the first setting section 301 and the second setting section 303 set the heating temperature of the non-contact heater 211 higher than that of the drum heater 213.
Note that the first setting unit 301 is an example of a setting unit that sets the temperature of the contact heating unit, and the second setting unit 303 is an example of a setting unit that sets the temperature of the non-contact heating unit.

Further, the first setting unit 301 sets the temperature of the drum heater 213 to less than 85°C, and the second setting unit 303 sets the heating temperature of the non-contact heater 211 to 140°C or more and 160°C or less, and the drum heater 213 It is more preferable to set the temperature to 30 to 90°C higher than that.

By setting the temperature in this manner, it is possible to have suitable drying properties and to suppress thermal deformation of the base material.

A presumed mechanism capable of suppressing thermal deformation of the base material will be described with reference to FIG. 8. In FIG. 8, the drum heater 213 at 70° C. and the back surface of the base material 20 are in contact. Further, the liquid 40 is attached to the front surface of the base material 20, and the non-contact heater 211 blows hot air at 150° C. toward the liquid 40.

The temperature of the liquid 40 becomes 100° C. or more due to the heat of the 150° C. hot air, and drying is accelerated. However, the influence of the 70°C drum heater 213 that is in contact with the base material 20 is dominant, and the heat of the 150°C hot air is blown onto the surface of the base material 20 from which the liquid is discharged. However, by setting the temperature of the drum heater 213 in contact with the drum heater 213 to be lower than the temperature at which the base material 20 can be thermally deformed, the temperature of the base material 20 can be maintained at a temperature state where no elongation occurs.

As shown in FIG. 7, one of the properties of OPP film, which is commonly used as a flexible packaging film, is that it is weak against heat, that is, it easily stretches when heated.
However, according to the present embodiment, even when an OPP film is used as a base material, the applied liquid can be dried at high speed while suppressing thermal deformation of the OPP film.

Moreover, when using a PET film or a nylon film as a base material other than OPP, for example, thermal deformation due to heating by the non-contact heater 211 is small as described above. Therefore, in that case, for example, if the temperature of the drum heater 21 is set to around 100° C. while the hot air temperature remains at 140° C. or higher and 160° C. or lower, the ink drying time is further shortened. In this way, by selecting the combination of the heating temperature by the non-contact heater 211 and the heating temperature by the drum heater 213 according to the material of the base material, drying of the liquid can be suitably promoted.

In addition, by using a cylindrical member around which the base material is wrapped as a contact heating means, the entire base material can be heated during the transport process of the base material during image formation, and the elongation of the base material can be suppressed while adhering to the base material. It is possible to quickly dry liquids.

In the above, ink is used as an example of the liquid, but the liquid is not limited to this. For example, a pre-treatment liquid may be used when applying the pre-treatment liquid to part or all of the base material prior to image formation. The present embodiment may also be applied to the drying of the post-processing liquid, or the drying of the post-processing liquid when the post-processing liquid is applied to part or all of the substrate after image formation.

[Second embodiment]
In the first embodiment, blowing hot air was described as an example of non-contact heating means. In this embodiment, an infrared ray (IR) heater is used as the non-contact heating means. An infrared heater is a heater that heats a heating target by irradiating it with infrared rays. The infrared heater may be of any wavelength from near-infrared to far-infrared, and the appropriate wavelength may be determined depending on the material of the liquid.

By using an infrared heater, effects such as high heat transfer efficiency, space saving, short preheating time, and easy control can be obtained.

Effects other than the above are similar to those described in the first embodiment.

Note that although blowing hot air and irradiation with infrared rays have been described above as examples of non-contact heating means, the present invention is not limited thereto. Further, although the drum heater 213 has been described as an example of heat transfer by contact, the present invention is not limited to this. For example, heat transfer using a planar heater may be used.

Although the drying device, liquid ejecting device, and drying method according to the embodiments have been described above, the present invention is not limited to the above embodiments, and various modifications and improvements can be made within the scope of the present invention. .

Next, one embodiment of an inkjet recording apparatus according to the present invention will be described using FIGS. 9 and 10. FIG. 9 is a schematic side view showing the inkjet recording apparatus according to this embodiment. The inkjet recording apparatus 100 of this embodiment is a line head type inkjet recording apparatus, and is a full line type (hereinafter also referred to as "line type").

In this embodiment, the first ink is a color ink and the second ink is a white ink.

The inkjet recording apparatus 100 includes an unwinding device 101, a non-permeable base material 102, a corona treatment device 103, a pretreatment liquid application device 104 (pretreatment liquid application means), a pretreatment liquid drying device 105, and an inkjet discharge head for color ink. 106 (first ink ejection means), white ink jet ejection head 107 (second ink ejection means), platen 108, hot air nozzle 109 (first drying means), drying device 129, drum heater 113 (second ink ejection means), 2), a hot air generator 112 facing the drum, and a winding device 117.

9 shows a configuration in which the inkjet recording apparatus 100 includes one drum heater 113, and FIG. 10 shows a configuration in which the inkjet recording apparatus 100 includes two drum heaters 113.

Each means and each step will be explained below.

<Unwinding means and unwinding process, winding means and winding process>
An unwinding device 101 and a winding device 117 are used to unwind and wind up the impermeable base material 102 in this embodiment.

The unwinding device 101 supplies the impermeable base material 102 stored in a roll to the conveyance path within the recording apparatus 100 by being rotationally driven.

The winding device 117 rotates and drives the non-permeable base material 102, on which an image is formed by applying ink, to wind it up and store it in a roll.

The impermeable base material 102 in this embodiment is a film-like base material that continues in the transport direction of the inkjet recording apparatus, and is transported along the transport path between the unwinding device 101 and the winding device 117. Further, the length of the impermeable base material 102 in the transport direction is longer than at least the transport path between the unwinding device 101 and the winding device 117. By using base materials that are continuous in the transport direction of the recording apparatus in this way, printing can be performed continuously for a long time.

<Corona treatment means and corona treatment process>
The corona treatment means performs corona treatment on the impermeable base material 102 by corona discharge to modify the surface of the impermeable base material 102. As the corona treatment means of this embodiment, a corona treatment device is used. 103 is illustrated. The corona treatment process is a process in which the impermeable base material 102 that has been transported through the process of unwinding the impermeable base material 102 is subjected to corona treatment by corona discharge to modify its surface.

Although corona treatment is not essential, it is preferable to perform it because it improves the adhesion and wettability of the pretreatment liquid to the impermeable substrate 102. Moreover, instead of corona treatment, atmospheric pressure plasma treatment, flame treatment, ultraviolet irradiation treatment, etc. may be performed.

Various known means can be used to perform the corona treatment. Further, various conditions (discharge amount, etc.) when performing corona treatment are not particularly limited, and can be changed as appropriate.

<Pre-treatment liquid application means and pre-treatment liquid application step>
The pretreatment liquid applying means is a means for applying a pretreatment liquid to the non-permeable substrate 102. A pretreatment liquid application device 104 is illustrated as a pretreatment liquid applying means in this embodiment, and the pretreatment liquid application device 104 rotates the roller to which the pretreatment liquid is applied so as to come into contact with the non-permeable substrate 102. The pretreatment liquid is applied to the surface of the non-permeable base material 102 by driving.

As a means for applying the pretreatment liquid, a roller to which the pretreatment liquid is attached is attached to the non-permeable base material 102.
Examples include, but are not limited to, means for contacting with.

The pretreatment liquid application process is a process of applying a pretreatment liquid to the non-permeable base material 102. In this embodiment, a pretreatment liquid is applied to the impermeable base material 102 that has been conveyed through the process of unwinding the impermeable base material.

By applying the pretreatment liquid to the impermeable base material 102, a pretreatment layer (also referred to as a surface treatment layer or the like) is formed on the impermeable base material 102. Note that the formation of the pretreatment layer is promoted by heating after applying the pretreatment liquid.

<First discharge means, second discharge means, first discharge step, and second discharge step>
The first ejection means and the first ejection step are means and steps for ejecting the first ink (color ink) onto the non-permeable substrate to which the pretreatment liquid has been applied. The second ejection means and the second ejection step are means and steps for ejecting the second ink (white ink) after heating the non-permeable substrate onto which the first ink (color ink) has been ejected. be. Note that the first ejecting means and the second ejecting means may be referred to as ink applying means, and the first ejecting step and the second ejecting step may be referred to as ink applying steps.

In this embodiment, as shown in FIG. 9, an inkjet ejection head 106 for color ink is used as the first ejection means, and an inkjet ejection head 107 for white ink is used as the second ejection means.

The inkjet ejection head 106 for color ink has a plurality of nozzle rows in which a plurality of nozzles are arranged, and is provided so that the direction of ink ejection from the nozzles faces the non-permeable base material 102. As a result, the inkjet ejection head 106 sequentially ejects liquids of magenta (M), cyan (C), yellow (Y), and black (K) onto the pretreatment layer on the non-permeable base material 102. do. Note that the order of ejection can be changed as appropriate.

The inkjet ejection head 107 for white ink is arranged downstream from the inkjet ejection head 106 . By overlaying white ink on top of color ink, it has the role of improving the visibility of printed matter from the surface of the transparent, non-permeable base material.

The inkjet ejection heads 106 and 107 of this embodiment are line type (full line type) inkjet ejection heads. The “line type inkjet ejection head” is an inkjet ejection head in which nozzles are arranged to eject ink over the entire width of the non-permeable base material 102 in the transport direction. Note that the width of the inkjet ejection head may be changed within a range that does not impair the effects of the present invention.

In industrial printing, since it is necessary to print a large amount at high speed, an inkjet recording method using a line-type inkjet ejection head as shown in FIG. 9 is preferable. On the other hand, in industrial printing, printing is performed continuously for a long time, so when a line-type head is used, the ink dries up in some nozzles that do not eject ink for a long time, resulting in ejection failure. may occur.

Therefore, in the ink application step, it is preferable to vibrate the ink interface within the nozzle in a nozzle that does not eject ink. By vibrating the ink interface in the nozzle, the ink in the nozzle and the ink in the ink flow path in the inkjet ejection head, such as the pressure chamber communicating with the nozzle, can be made uniform, and the ink inside the nozzle can be made uniform. The drying of the ink can be suppressed. This makes it possible to further suppress the occurrence of abnormal images due to ejection failure. Note that the ink interface within the nozzle is the ink interface that comes into contact with the atmosphere or gas.

In the inkjet ejection heads 106 and 107, the means for ejecting the ink by applying stimulation to the ink can be appropriately selected depending on the purpose, and includes, for example, a pressure device, a piezoelectric element, a vibration generator, and an ultrasonic oscillator. , lights, etc. Specific examples include piezoelectric actuators such as piezoelectric elements, shape memory alloy actuators that use metal phase change due to temperature changes, and electrostatic actuators that use electrostatic force.

Among these, in particular, by applying voltage to a piezoelectric element bonded to a position called a pressure chamber (also called a liquid chamber) in the ink flow path in an inkjet ejection head, the piezoelectric element is bent and the pressure chamber is closed. Preferably, the ink in the pressure chamber is pressurized by reducing the volume of the ink, and the ink is ejected as droplets from the nozzles of the inkjet ejection head.

In addition, among multiple nozzles that can eject such ink, in some nozzles that do not eject ink due to the shape of the image to be formed, a minute voltage that does not eject is applied to the piezoelectric element, and the inside of the nozzle is It is preferable to vibrate the ink interface.

Although related to other steps, the printing speed in the inkjet recording apparatus and inkjet recording method of this embodiment is preferably 30 m/min to 100 m/min. In this case, it can be suitably used in industrial applications where high-speed printing is required.

<Transport means and transport process>
The platen 108 guides the impermeable substrate 102 to be conveyed along the conveyance path. Further, conveyance rollers, etc., which are not labeled with reference numerals, are also used as conveyance means.

<Drying means and drying process>
The drying means referred to here is a means of heating the non-permeable substrate with warm air, infrared rays, a drum heater, etc. after the first ink (color ink) and second ink (white ink) are ejected. The drying step is a step of heating the non-permeable substrate onto which the first ink (color ink) has been ejected using hot air, infrared rays, a drum heater, or the like.

As shown in FIG. 10, as the drying means of this embodiment, a drum heater 113 whose temperature can be controlled and a hot air generator 112 arranged opposite to the drum heater 113 are arranged.

The drum heater 113 is a drum whose temperature can be adjusted, and it is necessary to provide a temperature difference between the temperature of the opposing hot air and a method of adjusting the temperature inside the drum using hot water and cooling water is desirable.

In addition, although the case where the color ink was used as the first ink and the white ink was used as the second ink was described above, the types and order of the inks are not limited to this. For example, the head 107 may use the white ink as the first ink and the color ink as the second ink, or may further include an inkjet ejection head as necessary, and may print green (G), red (R), violet (V), Light cyan (LC), light magenta (LM), white (W), metallic and/or other colored inks may be used.

Examples of the present invention will be described below, but the present invention is not limited to these Examples in any way.

ただし、前記一般式（１）中、Ｒはアルキル基を表す。 (Synthesis example 1 of resin particles)
<Synthesis of resin particles 1>
214 parts by mass of methyl methacrylate, 51 parts by mass of 2-ethylhexyl acrylate, 202 parts by mass of styrene, 2.2 parts by mass of Aqualon HS-10 (manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) as a reactive emulsifier, and 166 parts by mass of ion-exchanged water. A homogeneous milky white emulsion was obtained by emulsifying the mixture using a homomixer.
Next, in a 1 L flask equipped with a stirrer, a thermometer, a nitrogen gas introduction tube, and a reflux tube, 287 parts by mass of water with a pH of 3 that had been adjusted in advance with ion-exchanged water and sulfuric acid was charged, and nitrogen The temperature was raised to 70° C. while introducing.
Next, after adding 12.7 parts by mass of a 10% by mass Aqualon HS-10 (manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) aqueous solution and 8.7 parts by mass of a 5% by mass ammonium persulfate aqueous solution as a reactive emulsifier, the mixture was adjusted in advance. The prepared emulsion was continuously added dropwise over 2.5 hours.
Furthermore, 1.8 parts by mass of a 5% by mass ammonium persulfate aqueous solution was added every hour until 3 hours had elapsed from the start of the dropwise addition.
After the dropwise addition was completed, the mixture was aged at 70° C. for 2 hours, cooled, and the pH was adjusted to 7 to 8 with an aqueous sodium hydroxide solution to obtain a dispersion of resin particles 1.
In the obtained resin particles 1, the ratio of styrene to the structure represented by the following general formula (1) [Structure represented by the general formula (1)/(Structure represented by the general formula (1) + styrene)] ] was 0.75, and the glass transition temperature was 75°C.

However, in the general formula (1), R represents an alkyl group.

(Synthesis example 2 of resin particles)
<Synthesis of resin particles 2>
135 parts by mass of methyl methacrylate, 42 parts by mass of 2-ethylhexyl acrylate, 151 parts by mass of styrene, 2.2 parts by mass of Aqualon HS-10 (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.) as a reactive emulsifier, and 166 parts by mass of ion-exchanged water. A homogeneous milky white emulsion was obtained by emulsifying the mixture using a homomixer.
Next, into a 1L flask equipped with a stirrer, a thermometer, a nitrogen gas introduction tube, and a reflux tube, 287 parts by mass of water with a pH of 3 that had been adjusted with ion exchange water and sulfuric acid were charged, and nitrogen was added. The temperature was raised to 70° C. while the mixture was being introduced.
Next, after adding 12.7 parts by mass of a 10% by mass Aqualon HS-10 (manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) aqueous solution and 8.7 parts by mass of a 5% by mass ammonium persulfate aqueous solution as a reactive emulsifier, the mixture was adjusted in advance. The placed emulsion was continuously added dropwise over 2.5 hours.
Furthermore, 1.8 parts by mass of a 5% by mass ammonium persulfate aqueous solution was added every hour until 3 hours had elapsed from the start of the dropwise addition.
After the dropwise addition was completed, the mixture was aged at 70° C. for 2 hours, cooled, and the pH was adjusted to 7 to 8 with an aqueous sodium hydroxide solution to obtain a dispersion of resin particles 2.
In the obtained resin particles 2, the ratio [structure represented by general formula (1)/(structure represented by general formula (1) + styrene)] was 0.47, and the glass transition temperature was 80°C. there were.

(Synthesis example 3 of resin particles)
<Synthesis of resin particles 3>
148 parts by mass of methyl methacrylate, 120 parts by mass of 2-ethylhexyl acrylate, 49.3 parts by mass of styrene, 2.2 parts by mass of Aqualon HS-10 (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.) as a reactive emulsifier, and ion-exchanged water. A mixture consisting of 166 parts by mass was emulsified using a homomixer to obtain a homogeneous milky white emulsion.
Next, into a 1L flask equipped with a stirrer, a thermometer, a nitrogen gas introduction tube, and a reflux tube, 287 parts by mass of water with a pH of 3 that had been adjusted with ion exchange water and sulfuric acid were charged, and nitrogen was added. The temperature was raised to 70° C. while the mixture was being introduced.
Next, after adding 12.7 parts by mass of a 10% by mass Aqualon HS-10 (manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) aqueous solution and 8.7 parts by mass of a 5% by mass ammonium persulfate aqueous solution as a reactive emulsifier, the mixture was adjusted in advance. The placed emulsion was continuously added dropwise over 2.5 hours.
Furthermore, 1.8 parts by mass of a 5% by mass ammonium persulfate aqueous solution was added every hour until 3 hours had elapsed from the start of the dropwise addition.
After completion of the dropwise addition, the mixture was aged at 70° C. for 2 hours, cooled, and the pH was adjusted to 7 to 8 with an aqueous sodium hydroxide solution to obtain a dispersion of resin particles 3.
In the obtained resin particles 3, the ratio [structure represented by general formula (1)/(structure represented by general formula (1) + styrene)] was 0.75, and the glass transition temperature was 35°C. there were.

(Synthesis example 4 of resin particles)
<Synthesis of resin particles 4>
120 parts by mass of methyl methacrylate, 41.1 parts by mass of 2-ethylhexyl acrylate, 156 parts by mass of styrene, 2.2 parts by mass of Aqualon HS-10 (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.) as a reactive emulsifier, and ion-exchanged water. A mixture consisting of 166 parts by mass was emulsified using a homomixer to obtain a homogeneous milky white emulsion.
Next, into a 1L flask equipped with a stirrer, a thermometer, a nitrogen gas introduction tube, and a reflux tube, 287 parts by mass of water with a pH of 3 that had been adjusted with ion exchange water and sulfuric acid were charged, and nitrogen was added. The temperature was raised to 70° C. while the mixture was being introduced.
Next, after adding 12.7 parts by mass of a 10% by mass Aqualon HS-10 (manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) aqueous solution and 8.7 parts by mass of a 5% by mass ammonium persulfate aqueous solution as a reactive emulsifier, the mixture was adjusted in advance. The placed emulsion was continuously added dropwise over 2.5 hours.
Furthermore, 1.8 parts by mass of a 5% by mass ammonium persulfate aqueous solution was added every hour until 3 hours had elapsed from the start of the dropwise addition.
After the dropwise addition was completed, the mixture was aged at 70° C. for 2 hours, cooled, and the pH was adjusted to 7 to 8 with an aqueous sodium hydroxide solution to obtain a dispersion of resin particles 4.
In the obtained resin particles 4, the ratio [structure represented by general formula (1)/(structure represented by general formula (1) + styrene)] was 0.43, and the glass transition temperature was 80°C. there were.

(Synthesis example 5 of resin particles)
<Synthesis of resin particles 5>
Consisting of 254 parts by mass of methyl methacrylate, 63.3 parts by mass of 2-ethylhexyl acrylate, 2.2 parts by mass of Aqualon HS-10 (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.) as a reactive emulsifier, and 166 parts by mass of ion-exchanged water. The mixture was emulsified using a homomixer to obtain a homogeneous milky white emulsion.
Next, into a 1L flask equipped with a stirrer, a thermometer, a nitrogen gas introduction tube, and a reflux tube, 287 parts by mass of water with a pH of 3 that had been adjusted with ion exchange water and sulfuric acid were charged, and nitrogen was added. The temperature was raised to 70° C. while the mixture was being introduced.
Next, after adding 12.7 parts by mass of a 10% by mass Aqualon HS-10 (manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) aqueous solution and 8.7 parts by mass of a 5% by mass ammonium persulfate aqueous solution as a reactive emulsifier, the mixture was adjusted in advance. The placed emulsion was continuously added dropwise over 2.5 hours.
Furthermore, 1.8 parts by mass of a 5% by mass ammonium persulfate aqueous solution was added every hour until 3 hours had elapsed from the start of the dropwise addition.
After the dropwise addition was completed, the mixture was aged at 70° C. for 2 hours, cooled, and the pH was adjusted to 7 to 8 with an aqueous sodium hydroxide solution to obtain a dispersion of resin particles 5.
In the obtained resin particles 5, the ratio [structure represented by general formula (1)/(structure represented by general formula (1) + styrene)] was 1.0, and the glass transition temperature was 73°C. there were.

(Synthesis example 6 of resin particles)
<Synthesis of resin particles 6>
231 parts by mass of methyl methacrylate, 63.3 parts by mass of 2-ethylhexyl acrylate, 23 parts by mass of styrene, 2.2 parts by mass of Aqualon HS-10 (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.) as a reactive emulsifier, and ion-exchanged water. A mixture consisting of 166 parts by mass was emulsified using a homomixer to obtain a homogeneous milky white emulsion.
Next, into a 1L flask equipped with a stirrer, a thermometer, a nitrogen gas introduction tube, and a reflux tube, 287 parts by mass of water with a pH of 3 that had been adjusted with ion exchange water and sulfuric acid were charged, and nitrogen was added. The temperature was raised to 70° C. while the mixture was being introduced.
Next, after adding 12.7 parts by mass of a 10% by mass Aqualon HS-10 (manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) aqueous solution and 8.7 parts by mass of a 5% by mass ammonium persulfate aqueous solution as a reactive emulsifier, the mixture was adjusted in advance. The placed emulsion was continuously added dropwise over 2.5 hours.
Furthermore, 1.8 parts by mass of a 5% by mass ammonium persulfate aqueous solution was added every hour until 3 hours had elapsed from the start of the dropwise addition.
After the dropwise addition was completed, the mixture was aged at 70° C. for 2 hours, cooled, and the pH was adjusted to 7 to 8 with an aqueous sodium hydroxide solution to obtain a dispersion of resin particles 6.
In the obtained resin particles 6, the ratio [structure represented by general formula (1)/(structure represented by general formula (1) + styrene)] was 0.91, and the glass transition temperature was 75°C. there were.

(Preparation example 1 of pigment dispersion)
<Preparation of cyan pigment dispersion>
Each material was mixed according to the following recipe, and further circulated and dispersed for 7 hours using a disc-type bead mill (manufactured by Shinmaru Enterprises, KDL type, media: zirconia balls with a diameter of 0.3 mm) to obtain a cyan pigment dispersion. (Pigment solid content: 15% by mass).
[Prescription]
- Pigment Blue 15:3 (product name: LIONOL BLUE FG-7351, manufactured by Toyo Ink Co., Ltd.): 15 parts by mass - Anionic surfactant (Pionin A-51-B, manufactured by Takemoto Yushi Co., Ltd.): 2 parts by mass・Ion exchange water: 83 parts by mass

(Preparation example 2 of pigment dispersion)
<Preparation of magenta pigment dispersion>
In Preparation Example 1 of Pigment Dispersion, Pigment Blue 15:3 was changed to Pigment Red 122 (product name: Toner Magenta EO02, manufactured by Clariant Japan Co., Ltd.) in the same manner as in Preparation Example 1 of Pigment Dispersion. A magenta pigment dispersion was prepared (pigment solid content: 15% by mass).

(Preparation example 3 of pigment dispersion)
<Preparation of yellow pigment dispersion>
Same as Pigment Dispersion Preparation Example 1, except that Pigment Blue 15:3 was changed to Pigment Yellow 74 (product name: First Yellow 531, manufactured by Dainichiseika Kagyo Co., Ltd.) A yellow pigment dispersion liquid was prepared (pigment solid content: 15% by mass).

(Preparation example 4 of pigment dispersion)
<Preparation of black pigment dispersion>
A black pigment dispersion was prepared in the same manner as in Pigment Dispersion Preparation Example 1, except that Pigment Blue 15:3 was changed to carbon black pigment (trade name: Monarch 800, manufactured by Cabot). A liquid was prepared (pigment solid content: 15% by mass).

(Preparation example 5 of pigment dispersion)
<Preparation of white pigment dispersion>
25 parts by mass of titanium oxide (trade name: STR-100W, manufactured by Sakai Chemical Industry Co., Ltd.), 5 parts by mass of a pigment dispersant (trade name: TEGO Dispers 651, manufactured by Evonik), and 70 parts by mass of water were mixed, and the mixture was milled in a bead mill ( Product name: Research Lab, manufactured by Shinmaru Enterprises Co., Ltd.), zirconia beads with a diameter of 0.3 mm were dispersed at a filling rate of 60% and a speed of 8 m/s for 5 minutes to obtain a white pigment dispersion (pigment solid 25% by mass).

(Manufacturing example of ink and ink set)
Each material was mixed and stirred according to the ink formulations listed in Tables 1 to 11, and filtered through a polypropylene filter with an average pore size of 0.2 μm to produce each ink. Next, ink sets 1 to 11 were prepared by combining the inks listed in Tables 1 to 11.
Details of the components in Tables 1 to 11 are as follows.
・Surfactant (Surfynol 465, Nissin Chemical Industry Co., Ltd., acetylene glycol surfactant)
・Anti-mold agent (Proxel LV, manufactured by Avecia)

<Preparation of pretreatment liquid>
Each material was mixed and stirred according to the following recipe, and filtered through a filter (manufactured by Sartorius, Minisarto) with an average pore size of 5 μm to obtain a pretreatment liquid.
[Prescription]
・2,3-butanediol: 10 parts by mass ・3-methoxy-3-methyl-1-butanol: 10 parts by mass ・Calcium acetate monohydrate: 2.5 parts by mass ・Urethane resin (Superflex 500M, Daiichi (manufactured by Kogyo Seiyaku Co., Ltd.): 10 parts by mass (as solid content)
・Water: Remaining amount (total 100 parts by mass)

(Examples 1 to 11 and Comparative Examples 1 to 3)
<Image formation>
Next, the prepared cyan ink, magenta ink, yellow ink, black ink, and white ink were applied to a modified inkjet recording device (VC-60000, manufactured by Ricoh Co., Ltd.) using the combinations listed in Tables 12 to 25. An ink storage container was filled with the ink, and printing was performed under the following printing conditions.
[Printing conditions]
・Printing speed: 50m/min ・Resolution: 1200dpi x 1200dpi
- Printed image: A solid image of white ink was formed on top of solid images of black ink, cyan ink, magenta ink, and yellow ink.
・Base material: Biaxially oriented polypropylene (OPP) film (product name: Pylene P2161, manufactured by Toyobo Co., Ltd., average thickness 20 μm)
・Corona treatment device: Discharge amount 20W・min/m ²
・Pre-treatment liquid application means: Roll coater (coating amount 3g/m ² )
Note that in Example 11, printing was performed using ink set 3 in the same manner as in Example 3 except that the pretreatment liquid was not applied.

Next, evaluation was performed according to the following methods and evaluation criteria. The results are summarized in Tables 12 to 25.

<Film quality>
The film quality of the printed image at the end of printing was visually observed and evaluated based on the following criteria. In addition, cases where the evaluation was B or higher were judged to be practical.
[Evaluation criteria]
A: No abnormality is observed. B: No abnormality can be observed visually, but wrinkles on the film can be observed with a magnifying glass. C: Wrinkles can be observed visually in a part of the printed image. D: Wrinkles can be observed visually in the entire printed image. can

<Drying quality>
The drying quality at the end of printing was evaluated by rubbing the printed image with a nonwoven fabric and using the following criteria. In addition, cases where the evaluation was B or higher were judged to be practical.
[Evaluation criteria]
A: No abnormality is observed. B: No abnormality can be observed visually, but scratches on the printed image can be observed with a magnifying glass. C: Peeling can be observed in a part of the printed image with the naked eye. D: Peeling can be observed on the entire printed image with the naked eye. can be observed

<Blocking quality>
After printing is completed, cut out the image forming area into 6 cm square pieces, overlap them so that the image forming area and the unprinted surface of the base material are in contact with each other, sandwich this between two 10 cm x 10 cm square glass plates, and apply a load from above. It was left at room temperature (25° C.) for 24 hours under a pressure of 0.5 kg/cm ² and evaluated according to the following evaluation criteria. In addition, cases where the evaluation was B or higher were judged to be practical.
[Evaluation criteria]
A: Sticking, no transfer to the substrate side B: Slight sticking, transfer to the substrate side C: Sticking, transfer to the substrate side D: Sticking, to the substrate side Significant transcription of

<Abrasion resistance>
The image forming area was rubbed 30 times with a cotton cloth under a load of 200 g, and the condition of the image was visually observed and evaluated using the following evaluation criteria. In addition, cases where the evaluation was B or higher were judged to be practical.
[Evaluation criteria]
A: No peeling of the image B: Slight peeling of the image C: Peeling of the image and part of the base material exposed D: Significant exposure of the base material over the entire image forming area

ただし、前記一般式（１）中、Ｒはアルキル基を表す。
＜６＞ 前記基材に前記インクを付与する前に、前記基材に前処理液を付与する前処理液付与手段を有し、
前記前処理液は樹脂を含有する前記＜１＞から＜５＞のいずれかに記載の印刷装置である。
＜７＞ 前記基材が非浸透性基材である前記＜１＞から＜６＞のいずれかに記載の印刷装置である。
＜８＞ 前記基材は平均厚みが３０μｍ以下であり、かつ延伸ポリプロピレンフィルム又はポリエステルフィルムである前記＜１＞から＜７＞のいずれかに記載の印刷装置である。
＜９＞ インクジェット方式の印刷に用いられる前記＜１＞から＜８＞のいずれかに記載の印刷装置である。
＜１０＞ 基材にインクを付与するインク付与工程と、前記インクが付与された前記基材を乾燥させる乾燥工程と、を含む印刷方法であって、
前記乾燥工程は、前記基材の前記インクが付与された面を非接触で加熱する非接触加熱処理と、前記基材の前記インクが付与される面の裏側に接触する接触加熱処理とを含み、前記接触加熱処理の加熱温度より、前記非接触加熱処理の加熱温度の方が高い工程であり、
前記インクは、色材、樹脂、水、及び有機溶剤を含み、
前記有機溶剤として沸点が１８０℃以上である有機溶剤を少なくとも１種含み、前記インクの全量に対する前記沸点が１８０℃以上である有機溶剤の含有量が１５質量％以上であり、
前記インクは、熱重量測定ＴＧにおいて、下記数式（１）によって求められる減量率Ａ（単位％）が－９５％となるときの測定時間が、３０分間以下であることを特徴とする印刷方法である。

ただし、前記「測定結果から得られるインクの減量率（％）」とは、インクの熱重量測定の結果得られるインクの減量率である。
前記「飽和減量率（％）」とは、測定結果から５分ごとのインクの減量率の差分を算出し、前記差分の絶対値が０．１％未満となる測定時間におけるインクの減量率（％）である。
＜１１＞ 前記インク付与工程の前に、前記基材に前処理液を付与する前処理液付与工程を含む前記＜１０＞に記載の印刷方法である。
＜１２＞ シアンインク、マゼンタインク、イエローインク、ブラックインク、及びホワイトインクから選択される少なくとも２種からなるインクセットであって、
前記シアンインク、マゼンタインク、イエローインク、ブラックインク、及びホワイトインクから選択される少なくとも２種のインクは、いずれも色材、樹脂、水、及び有機溶剤を含み、
前記有機溶剤として沸点が１８０℃以上である有機溶剤を少なくとも１種含み、前記インクの全量に対する前記沸点が１８０℃以上である有機溶剤の含有量が１５質量％以上であり、
熱重量測定ＴＧにおいて、下記数式（１）によって求められる減量率Ａ（単位％）が－９５％となるときの測定時間が、３０分間以下であることを特徴とするインクセットである。

ただし、前記「測定結果から得られるインクの減量率（％）」とは、インクの熱重量測定の結果得られるインクの減量率である。
前記「飽和減量率（％）」とは、測定結果から５分ごとのインクの減量率の差分を算出し、前記差分の絶対値が０．１％未満となる測定時間におけるインクの減量率（％）である。
＜１３＞ 樹脂を含有する前処理液と、
シアンインク、マゼンタインク、イエローインク、ブラックインク、及びホワイトインクから選択される少なくとも１種であるインクと、を有する前処理液とインクのセットであって、
前記シアンインク、マゼンタインク、イエローインク、ブラックインク、及びホワイトインクから選択される少なくとも１種のインクは、色材、樹脂、水、及び有機溶剤を含み、
前記有機溶剤として沸点が１８０℃以上である有機溶剤を少なくとも１種含み、前記インクの全量に対する前記沸点が１８０℃以上である有機溶剤の含有量が１５質量％以上であり、
熱重量測定ＴＧにおいて、下記数式（１）によって求められる減量率Ａ（単位％）が－９５％となるときの測定時間が、３０分間以下であることを特徴とする前処理液とインクのセットである。

ただし、前記「測定結果から得られるインクの減量率（％）」とは、インクの熱重量測定の結果得られるインクの減量率である。
前記「飽和減量率（％）」とは、測定結果から５分ごとのインクの減量率の差分を算出し、前記差分の絶対値が０．１％未満となる測定時間におけるインクの減量率（％）である。 Examples of aspects of the present invention are as follows.
<1> A printing device having an ink and a drying mechanism for drying a base material to which the ink is applied,
The drying mechanism includes a non-contact heating means that heats a surface of the base material to which the ink is applied in a non-contact manner, and a contact heating means that contacts the back side of the surface of the base material to which the ink is applied. a drying mechanism in which the non-contact heating means has a higher heating temperature than the contact heating means;
The ink contains a coloring material, a resin, water, and an organic solvent,
The organic solvent includes at least one organic solvent having a boiling point of 180° C. or higher, and the content of the organic solvent having a boiling point of 180° C. or higher based on the total amount of the ink is 15% by mass or higher,
The printing apparatus is characterized in that the measurement time of the ink is 30 minutes or less when the weight loss rate A (unit %) determined by the above formula (1) becomes -95% in thermogravimetric measurement TG. be.
<2> The printing apparatus according to <1>, wherein the heating temperature of the contact heating means is less than 85°C.
<3> The printing device according to any one of <1> to <2>, wherein the heating temperature of the non-contact heating means is 30° C. or more and 90° C. or less higher than the heating temperature of the contact heating means.
<4> The printing device according to any one of <1> to <3>, wherein the resin in the ink contains an acrylic resin.
<5> The acrylic resin has styrene and a structure represented by the following general formula (1), and the ratio of the styrene to the structure represented by the general formula (1) [the ratio of the styrene to the structure represented by the general formula (1)] The printing device according to <4>, wherein the structure represented by the general formula (1) + styrene is 0.45 or more and 0.9 or less.

However, in the general formula (1), R represents an alkyl group.
<6> A pretreatment liquid applying means for applying a pretreatment liquid to the base material before applying the ink to the base material,
In the printing device according to any one of <1> to <5>, the pretreatment liquid contains a resin.
<7> The printing device according to any one of <1> to <6>, wherein the base material is a non-permeable base material.
<8> The printing device according to any one of <1> to <7>, wherein the base material has an average thickness of 30 μm or less and is a stretched polypropylene film or a polyester film.
<9> The printing device according to any one of <1> to <8>, which is used for inkjet printing.
<10> A printing method comprising an ink applying step of applying ink to a base material, and a drying step of drying the base material to which the ink has been applied,
The drying step includes a non-contact heating treatment in which the surface of the base material to which the ink is applied is heated in a non-contact manner, and a contact heating treatment in which the back side of the surface of the base material to which the ink is applied is contacted. , a step in which the heating temperature of the non-contact heat treatment is higher than the heating temperature of the contact heat treatment,
The ink contains a coloring material, a resin, water, and an organic solvent,
The organic solvent includes at least one organic solvent having a boiling point of 180° C. or higher, and the content of the organic solvent having a boiling point of 180° C. or higher based on the total amount of the ink is 15% by mass or higher,
The printing method is characterized in that the measurement time of the ink is 30 minutes or less when the weight loss rate A (unit: %) determined by the following mathematical formula (1) becomes -95% in thermogravimetry TG. be.

However, the above-mentioned "ink loss rate (%) obtained from measurement results" is the ink weight loss rate obtained as a result of thermogravimetric measurement of the ink.
The above-mentioned "saturated weight loss rate (%)" is calculated by calculating the difference in ink weight loss rate every 5 minutes from the measurement results, and the ink weight loss rate (%) during the measurement time when the absolute value of the difference is less than 0.1%. %).
<11> The printing method according to <10>, including a pretreatment liquid application step of applying a pretreatment liquid to the base material before the ink application step.
<12> An ink set consisting of at least two types selected from cyan ink, magenta ink, yellow ink, black ink, and white ink,
At least two types of ink selected from the cyan ink, magenta ink, yellow ink, black ink, and white ink each contain a coloring material, a resin, water, and an organic solvent,
The organic solvent includes at least one organic solvent having a boiling point of 180° C. or higher, and the content of the organic solvent having a boiling point of 180° C. or higher based on the total amount of the ink is 15% by mass or higher,
The ink set is characterized in that in thermogravimetric measurement TG, the measurement time when the weight loss rate A (unit: %) determined by the following formula (1) is -95% is 30 minutes or less.

However, the above-mentioned "ink loss rate (%) obtained from measurement results" is the ink weight loss rate obtained as a result of thermogravimetric measurement of the ink.
The above-mentioned "saturated weight loss rate (%)" is calculated from the measurement results by calculating the difference in the ink weight loss rate every 5 minutes, and the ink weight loss rate (%) during the measurement time when the absolute value of the difference is less than 0.1%. %).
<13> A pretreatment liquid containing a resin,
A pretreatment liquid and ink set comprising at least one ink selected from cyan ink, magenta ink, yellow ink, black ink, and white ink,
At least one ink selected from cyan ink, magenta ink, yellow ink, black ink, and white ink contains a coloring material, a resin, water, and an organic solvent,
The organic solvent includes at least one organic solvent having a boiling point of 180°C or higher, and the content of the organic solvent having a boiling point of 180°C or higher based on the total amount of the ink is 15% by mass or higher,
A set of pre-treatment liquid and ink, characterized in that in thermogravimetric measurement TG, the measurement time when the weight loss rate A (unit: %) obtained by the following formula (1) is -95% is 30 minutes or less. It is.

However, the above-mentioned "ink loss rate (%) obtained from measurement results" is the ink weight loss rate obtained as a result of thermogravimetric measurement of the ink.
The above-mentioned "saturated weight loss rate (%)" is calculated from the measurement results by calculating the difference in the ink weight loss rate every 5 minutes, and the ink weight loss rate (%) during the measurement time when the absolute value of the difference is less than 0.1%. %).

The printing device according to any one of <1> to <9>, the printing method according to any one of <10> to <11>, the ink set according to <12>, and the ink set according to <13> According to the set of pretreatment liquid and ink described above, various problems in the prior art can be solved and the object of the present invention can be achieved.

1 Liquid discharge unit 1K, 1Y, 1C, 1M Liquid discharge head 2 Drying unit (an example of a drying device)
3 supply unit 4 discharge unit 5 conveyance unit 5a conveyance roller 10 conveyance direction 20 base material (an example of a base material made of stretched polypropylene)
20a Front side of base material 20b Back side of base material 40 Liquid (an example of water-based ink)
100 Inkjet recording device (an example of an image forming device, printing device, liquid ejection device)
101 Unwinding device 102 Impermeable base material 103 Corona treatment device 104 Pretreatment liquid application device 105 Pretreatment liquid drying device 106 Inkjet discharge head for color ink 107 Inkjet discharge head for white ink 108 Platen 109 Hot air nozzle 110 Infrared heater ( (first drying means)
112 Hot air generator facing the drum 113 Drum heater (second drying means)
114 Warm air nozzle (third ink drying device)
115 Drum heater (third ink drying device)
116 Warm air nozzle (intercolor heating device for color ink and white ink)
117 Winding device 118 Temperature detection sensor 119 Control device 120 Cooling device 129 Drying device 200 Control device 210 Hot air temperature sensor 211 Non-contact heater (an example of non-contact heating means)
211a, 211b nozzle 212 drum temperature sensor 213 drum heater (an example of a contact heating means, an example of a cylindrical member)
301 First setting section (an example of first setting means)
302 Drum temperature detection section 303 Second setting section (an example of second setting means)
304 Hot air temperature detection section

Japanese Patent Application Publication No. 2014-238191

Claims (13)

A printing device having an ink and a drying mechanism for drying a substrate to which the ink is applied,
The drying mechanism includes a non-contact heating means that heats a surface of the base material to which the ink is applied in a non-contact manner, and a contact heating means that contacts the back side of the surface of the base material to which the ink is applied. a drying mechanism in which the non-contact heating means has a higher heating temperature than the contact heating means;
The ink contains a coloring material, a resin, water, and an organic solvent,
The organic solvent includes at least one organic solvent having a boiling point of 180° C. or higher, and the content of the organic solvent having a boiling point of 180° C. or higher based on the total amount of the ink is 15% by mass or higher,
The ink is characterized in that, in thermogravimetric measurement TG under the following measurement conditions , the measurement time when the weight loss rate A (unit %) obtained by the following mathematical formula (1) is -95% is 30 minutes or less. printing device.

However, in the above formula (1), the "ink loss rate (%) obtained from the measurement results" is the ink weight loss rate obtained as a result of thermogravimetric measurement of the ink. The above-mentioned "saturated weight loss rate (%)" is calculated by calculating the difference in ink weight loss rate every 5 minutes from the measurement results, and the ink weight loss rate (%) during the measurement time when the absolute value of the difference is less than 0.1%. %).
[Measurement condition]
・Temperature program: Set temperature 100℃
・Heating rate: 10℃/min
・Holding time after heating up: 70 minutes
・Measurement start temperature: 25℃
・Control thermocouple: Furnace
・Bread: Al (aluminum)
・Sample amount: 10mg±0.3mg The printing apparatus according to claim 1, wherein the heating temperature of the contact heating means is less than 85°C. 3. The printing apparatus according to claim 1, wherein the heating temperature of the non-contact heating means is higher than the heating temperature of the contact heating means by 30° C. or more and 90° C. or less. The printing device according to any one of claims 1 to 3, wherein the resin in the ink contains an acrylic resin. The acrylic resin has styrene and a structure represented by the following general formula (1), and the ratio of the styrene to the structure represented by the general formula (1) [the structure represented by the general formula (1)] /(Structure represented by general formula (1) + styrene)] is 0.45 or more and 0.9 or less, the printing device according to claim 4.

However, in the general formula (1), R represents an alkyl group. a pretreatment liquid applying means for applying a pretreatment liquid to the substrate before applying the ink to the substrate;
6. The printing apparatus according to claim 1, wherein the pretreatment liquid contains a resin. The printing device according to any one of claims 1 to 6, wherein the base material is a non-permeable base material. 8. The printing apparatus according to claim 1, wherein the base material has an average thickness of 30 μm or less and is a stretched polypropylene film or a polyester film. The printing device according to any one of claims 1 to 8, which is used for inkjet printing. A printing method comprising an ink applying step of applying ink to a base material, and a drying step of drying the base material to which the ink has been applied,
The drying step includes a non-contact heating treatment in which the surface of the base material to which the ink is applied is heated in a non-contact manner, and a contact heating treatment in which the back side of the surface of the base material to which the ink is applied is contacted. , a step in which the heating temperature of the non-contact heat treatment is higher than the heating temperature of the contact heat treatment,
The ink contains a coloring material, a resin, water, and an organic solvent,
The organic solvent includes at least one organic solvent having a boiling point of 180° C. or higher, and the content of the organic solvent having a boiling point of 180° C. or higher based on the total amount of the ink is 15% by mass or higher,
The ink is characterized in that, in thermogravimetric measurement TG under the following measurement conditions , the measurement time when the weight loss rate A (unit %) obtained by the following mathematical formula (1) is -95% is 30 minutes or less. printing method.

However, in the above formula (1), the "ink loss rate (%) obtained from the measurement results" is the ink weight loss rate obtained as a result of thermogravimetric measurement of the ink. The above-mentioned "saturated weight loss rate (%)" is calculated by calculating the difference in ink weight loss rate every 5 minutes from the measurement results, and the ink weight loss rate (%) during the measurement time when the absolute value of the difference is less than 0.1%. %).
[Measurement condition]
・Temperature program: Set temperature 100℃
・Heating rate: 10℃/min
・Holding time after heating up: 70 minutes
・Measurement start temperature: 25℃
・Control thermocouple: Furnace
・Bread: Al (aluminum)
・Sample amount: 10mg±0.3mg The printing method according to claim 10, further comprising a pretreatment liquid application step of applying a pretreatment liquid before the ink application step. An ink set consisting of at least two types selected from cyan ink, magenta ink, yellow ink, black ink, and white ink,
At least two types of ink selected from the cyan ink, magenta ink, yellow ink, black ink, and white ink each contain a coloring material, a resin, water, and an organic solvent,
The organic solvent includes at least one organic solvent having a boiling point of 180° C. or higher, and the content of the organic solvent having a boiling point of 180° C. or higher based on the total amount of the ink is 15% by mass or higher,
An ink set characterized in that, in thermogravimetric measurement TG under the following measurement conditions , the measurement time is 30 minutes or less when the weight loss rate A (unit: %) determined by the following formula (1) is -95%.

However, in the above formula (1), the "ink loss rate (%) obtained from the measurement results" is the ink weight loss rate obtained as a result of thermogravimetric measurement of the ink. The above-mentioned "saturated weight loss rate (%)" is calculated by calculating the difference in ink weight loss rate every 5 minutes from the measurement results, and the ink weight loss rate (%) during the measurement time when the absolute value of the difference is less than 0.1%. %).
[Measurement condition]
・Temperature program: Set temperature 100℃
・Heating rate: 10℃/min
・Holding time after heating up: 70 minutes
・Measurement start temperature: 25℃
・Control thermocouple: Furnace
・Bread: Al (aluminum)
・Sample amount: 10mg±0.3mg a pretreatment liquid containing resin;
A pretreatment liquid and ink set comprising at least one ink selected from cyan ink, magenta ink, yellow ink, black ink, and white ink,
At least one ink selected from cyan ink, magenta ink, yellow ink, black ink, and white ink contains a coloring material, a resin, water, and an organic solvent,
The organic solvent includes at least one organic solvent having a boiling point of 180° C. or higher, and the content of the organic solvent having a boiling point of 180° C. or higher based on the total amount of the ink is 15% by mass or higher,
A pretreatment liquid characterized in that, in thermogravimetric measurement TG under the following measurement conditions , the measurement time when the weight loss rate A (unit %) obtained by the following formula (1) is -95% is 30 minutes or less and ink set.

However, in the above formula (1), the "ink loss rate (%) obtained from the measurement results" is the ink weight loss rate obtained as a result of thermogravimetric measurement of the ink. The above-mentioned "saturated weight loss rate (%)" is calculated by calculating the difference in ink weight loss rate every 5 minutes from the measurement results, and the ink weight loss rate (%) during the measurement time when the absolute value of the difference is less than 0.1%. %).
[Measurement condition]
・Temperature program: Set temperature 100℃
・Heating rate: 10℃/min
・Holding time after heating up: 70 minutes
・Measurement start temperature: 25℃
・Control thermocouple: Furnace
・Bread: Al (aluminum)
・Sample amount: 10mg±0.3mg

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