JP7286965B2 - SET OF INK AND CLEANING LIQUID, CLEANING METHOD, INKJET PRINTING METHOD, AND INKJET PRINTING APPARATUS - Google Patents

Description

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

Conventionally, dye inks have been the mainstream of inkjet inks due to their good color development and high reliability. Therefore, in recent years, the use of pigment ink has been increasing.

During continuous recording, such pigment ink adheres to the recording head or the like, coagulates, and dries, which may reduce the ejection stability of the pigment ink. For this reason, it is necessary to wash off the ink adhering to the recording head, etc., in order to ensure the ejection stability of the pigment ink. There is the problem of insufficient power.

In addition, in order to form and dry images at high speeds of several tens of meters per minute in order to meet the needs for high productivity in the fields of commercial and industrial printing, various methods for efficiently drying printed matter at high speeds have been investigated. there is
Therefore, an ink containing resin particles with a high glass transition temperature (Tg) has been proposed as an ink that can improve productivity (see, for example, Patent Document 1).
Also, a set of ink and cleaning liquid is proposed in which an ink containing water and a resin and a cleaning liquid containing water and an organic solvent are combined (see, for example, Patent Document 2).

SUMMARY OF THE INVENTION An object of the present invention is to provide a set of an ink and a cleaning liquid that has excellent cleaning properties even when using an ink containing a resin with a high glass transition temperature that can improve productivity.

The ink and cleaning liquid set of the present invention as a means for solving the above-mentioned problems comprises an ink containing a coloring material and a resin, and a cleaning liquid containing water and an organic solvent. The glass transition temperature is 40° C. or higher and 90° C. or lower, and the swelling rate calculated based on the following formula 1 from the mass before and after immersing the ink film obtained by drying the ink in the cleaning liquid is 10% or more. It is a set of ink and cleaning liquid.
Swelling rate (%) = 100 × [(B - A) / A] ... Equation 1
However, in Equation 1, A represents the mass of the ink film before immersion, and B represents the mass of the ink film after immersion.

ADVANTAGE OF THE INVENTION According to this invention, even when using the ink containing resin with a high glass transition temperature which can raise productivity, the set of the ink and washing|cleaning liquid which have the outstanding washability can be provided.

FIG. 1 is a schematic diagram showing an example of a cleaning apparatus used in the present invention. FIG. 2 is a diagram showing an example of an image forming apparatus that implements the image forming method of the present invention. 3 is a perspective explanatory view showing an example of a main tank of the image forming apparatus of FIG. 2. FIG.

(Ink and cleaning solution set)
The ink and cleaning liquid set of the present invention includes an ink containing a coloring material and a resin, and a cleaning liquid containing water and an organic solvent, and the glass transition temperature of the ink in a dry state is 40° C. or higher and 90° C. or lower. The ink film obtained by drying the ink has a swelling rate of 10% or more calculated based on the following formula 1 from the mass before and after immersion in the cleaning liquid, and further contains other components as necessary.
Swelling rate (%) = 100 × [(B - A) / A] ... Equation 1
However, in Equation 1, A represents the mass of the ink film before immersion, and B represents the mass of the ink film after immersion.

The ink and cleaning liquid set of the present invention does not pay attention to the relationship between the ink, which can achieve high productivity, and the cleaning liquid used when wiping the ink, and the ink does not affect the recording head and the flow. This is based on the knowledge that the cleaning power using the conventional cleaning liquid is insufficient because it dries on roads and the like and tends to stick, and maintenance becomes an issue.

The set of the ink and the cleaning liquid of the present invention can increase productivity by cleaning the dried ink adhered or fixed to the recording head or the like with an appropriate combination of cleaning liquids to swell the ink. Even when an ink containing a resin with a high transition temperature is used, excellent washability can be achieved.
By including a resin having a high glass transition temperature in the ink, the adhesion between the pigments in the dried state and between the pigments and the recording medium is improved, and an ink having excellent abrasion resistance can be realized.
The glass transition temperature (Tg) of the ink in a dry state is 40° C. or higher and 90° C. or lower, preferably 65° C. or higher and 85° C. or lower. The tackiness of the ink layer in the image state is reduced, and it is possible to suppress peeling due to contact with the internal members of the device immediately after drying and peeling caused by adhesion between images, resulting in an ink that supports high productivity. be done.
The glass transition temperature (Tg) of the dried ink can be measured as follows.
[Measurement of glass transition temperature (Tg) of dried ink]
5 g of ink is dropped on a Teflon (registered trademark) petri dish with a diameter of 4 cm and dried in an environment of 50° C. for 72 hours to obtain a dried ink product.
The dried ink obtained is measured using a differential scanning calorimeter (Thermo plus EVO2 DSC8231, manufactured by Rigaku Corporation) to calculate the glass transition temperature (Tg).

Furthermore, the glass transition temperature (Tg) of the resin in the ink is preferably 60° C. or higher, more preferably 100° C. or lower, from the viewpoint of realizing high productivity.

The swelling rate calculated based on the following formula 1 from the mass before and after the ink film obtained by drying the ink is immersed in the cleaning liquid is 10% or more, preferably 14% or more, and 30% or more and 150%. The following are more preferred. When the swelling ratio is 10% or more, the organic solvent in the cleaning liquid causes the resin and pigment in the ink to swell with respect to the ink in a dry state. The action facilitates wiping, and excellent cleanability can be achieved.
Swelling rate (%) = 100 × [(B - A) / A] ... Equation 1
However, in Equation 1, A represents the mass of the ink film before immersion, and B represents the mass of the ink film after immersion.
Here, the swelling rate of the ink film with respect to the cleaning liquid can be obtained as follows.
5 g of ink is dropped on a petri dish of Teflon (registered trademark) with a diameter of 4 cm and dried in an environment of 50° C. for 72 hours to obtain a dried ink film.
A 1-cm square piece is cut out from the dried ink film, and the mass is measured. Soak the cut-out ink film in a sufficient amount of cleaning liquid, leave it at room temperature (25°C) for 3 minutes, remove it from the cleaning liquid, and wipe it with a Kimwipe (manufactured by Nippon Paper Crecia Co., Ltd.) so that the cleaning liquid adhering to the surface cannot be visually confirmed. ), the mass is measured, and the swelling ratio is calculated from Equation 1 above.

<Ink>
Organic solvents, water, coloring materials, resins, additives, and the like used in the ink are described below.

<Organic solvent>
The organic solvent used in the present invention is not particularly limited, and any water-soluble organic solvent can be used. Examples thereof include polyhydric alcohols, ethers such as polyhydric alcohol alkyl ethers and polyhydric alcohol aryl ethers, nitrogen-containing heterocyclic compounds, amides, amines, and sulfur-containing compounds.
Examples of polyhydric alcohols include ethylene glycol, diethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 2 , 3-butanediol, 3-methyl-1,3-butanediol, triethylene glycol, polyethylene glycol, polypropylene glycol, 1,2-pentanediol, 1,3-pentanediol, 1,4-pentanediol, 2, 4-pentanediol, 1,5-pentanediol, 1,2-hexanediol, 1,6-hexanediol, 1,3-hexanediol, 2,5-hexanediol, 1,5-hexanediol, glycerin, 1 , 2,6-hexanetriol, 2-ethyl-1,3-hexanediol, ethyl-1,2,4-butanetriol, 1,2,3-butanetriol, 2,2,4-trimethyl-1,3 - pentanediol, petriol and the like.
Examples of polyhydric alcohol alkyl ethers include ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, tetraethylene glycol monomethyl ether, and propylene glycol monoethyl ether. .
Examples of polyhydric alcohol aryl ethers include ethylene glycol monophenyl ether and ethylene glycol monobenzyl ether.
Examples of nitrogen-containing heterocyclic compounds include 2-pyrrolidone, N-methyl-2-pyrrolidone, N-hydroxyethyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, ε-caprolactam, and γ-butyrolactone. etc.
Examples of amides include formamide, N-methylformamide, N,N-dimethylformamide, 3-methoxy-N,N-dimethylpropionamide, 3-butoxy-N,N-dimethylpropionamide and the like.
Examples of amines include monoethanolamine, diethanolamine, triethylamine and the like.
Examples of sulfur-containing compounds include dimethylsulfoxide, sulfolane, thiodiethanol and the like.
Other organic solvents include propylene carbonate and ethylene carbonate.
It is preferable to use an organic solvent having a boiling point of 250° C. or less because it not only functions as a wetting agent but also provides good drying properties.

As the organic solvent, polyol compounds having 8 or more carbon atoms and glycol ether compounds are also preferably used. Examples of polyol compounds having 8 or more carbon atoms include 2-ethyl-1,3-hexanediol and 2,2,4-trimethyl-1,3-pentanediol.
Examples of glycol ether compounds include polyhydric alcohol alkyl ethers such as ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, tetraethylene glycol monomethyl ether, and propylene glycol monoethyl ether. such as polyhydric alcohol aryl ethers such as ethylene glycol monophenyl ether and ethylene glycol monobenzyl ether.

A polyol compound having 8 or more carbon atoms and a glycol ether compound can improve ink permeability when paper is used as a recording medium.

The content of the organic solvent in the ink is not particularly limited and can be appropriately selected according to the purpose. 20% by mass or more and 60% by mass or less is more preferable.

<Water>
The content of water in the ink is not particularly limited and can be appropriately selected according to the purpose. % or more and 60 mass % or less is more preferable.

<Color material>
The coloring material is not particularly limited, and pigments and dyes can be used.
An inorganic pigment or an organic pigment can be used as the pigment. These may be used individually by 1 type, and may use 2 or more types together. Mixed crystals may also be used as pigments.
Examples of pigments that can be used include black pigments, yellow pigments, magenta pigments, cyan pigments, white pigments, green pigments, orange pigments, glossy color pigments such as gold and silver, and metallic pigments.
As inorganic pigments, in addition to titanium oxide, iron oxide, calcium carbonate, barium sulfate, aluminum hydroxide, barium yellow, cadmium red, and chrome yellow, carbon black produced by known methods such as contact method, furnace method, thermal method, etc. can be used.
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, quinophthalone pigments, etc.). , dye chelates (eg, basic dye chelates, acid dye chelates, etc.), nitro pigments, nitroso pigments, aniline black, and the like. 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).
Further, for color, C.I. 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. I. Pigment Orange 5, 13, 16, 17, 36, 43, 51, C.I. 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 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. 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.

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

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

As a method of dispersing the pigment to obtain an ink, a method of introducing a hydrophilic functional group into the pigment to make it a self-dispersing pigment, a method of coating the surface of the pigment with a resin and dispersing the pigment, and a method of dispersing the pigment using a dispersant. methods and the like.
As a method of making a self-dispersing pigment by introducing a hydrophilic functional group into a pigment, for example, a method of adding a functional group such as a sulfone group or a carboxyl group to a pigment (for example, carbon) to make it dispersible in water. etc.
Examples of the method of coating the surface of the pigment with a resin to disperse it include a method of encapsulating the pigment in microcapsules and making it dispersible in water. This can be rephrased as a resin-coated pigment. In this case, all the pigments mixed in the ink need not be coated with a 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. may be
Examples of the method of dispersing using a dispersant include a method of dispersing using a known low-molecular-weight dispersant and high-molecular-weight dispersant typified by surfactants.
As the dispersant, it is possible to use, for example, anionic surfactants, cationic surfactants, amphoteric surfactants, nonionic surfactants, etc. depending on the pigment.
As a dispersant, RT-100 (nonionic surfactant) manufactured by Takemoto Oil & Fat Co., Ltd. and sodium naphthalenesulfonate formalin condensate can also be suitably used as a dispersant.
A dispersing agent may be used individually by 1 type, or may use 2 or more types together.

<Pigment dispersion>
Inks can be obtained by mixing materials such as water and organic solvents with pigments. Ink can also be produced by mixing a pigment with water, a dispersant, and the like to form a pigment dispersion, and then mixing materials such as water and an organic solvent.
The pigment dispersion is obtained by mixing and dispersing water, a pigment, a pigment dispersant, and optionally other components, and adjusting the particle size. Dispersion should be carried out using a disperser.
The particle size of the pigment in the pigment dispersion is not particularly limited, but the dispersion stability of the pigment is improved, and the image quality such as ejection stability and image density is improved, so the maximum frequency is 20 nm in terms of maximum number. 500 nm or less is preferable, and 20 nm or more and 150 nm or less is more preferable.
The particle size of the pigment can be measured using a particle size analyzer (Nanotrack Wave-UT151, manufactured by Microtrack Bell Co., Ltd.).
The content of the pigment in the pigment dispersion is not particularly limited and can be appropriately selected according to the purpose. 50% by mass or less is preferable, and 0.1% by mass or more and 30% by mass or less is more preferable.
It is preferable to filter coarse particles with a filter, a centrifugal separator, or the like, and deaerate the pigment dispersion, if necessary.

<Resin>
The type of resin contained in the ink is not particularly limited as long as it is contained in the ink as a fixing resin, and can be appropriately selected according to the purpose. resins, vinyl acetate resins, styrene resins, butadiene resins, styrene-butadiene resins, vinyl chloride resins, acrylic-styrene resins, acrylic-silicone resins, and the like.

The resin in the ink is preferably contained as resin particles. Ink can be obtained by mixing resin particles in a resin emulsion state in which water is dispersed as a dispersion medium with a material such as a coloring material or an organic solvent. As the resin particles, appropriately synthesized ones may be used, or commercially available products may be used. These may be used singly or in combination of two or more resin particles.

The volume average particle diameter of the resin particles is not particularly limited and can be appropriately selected according to the intended purpose. It is more preferably 10 nm or more and 200 nm or less, and particularly preferably 10 nm or more and 100 nm or less. Furthermore, it is more preferably 20 nm or more and 45 nm or less in order to fulfill the function of a dispersing aid for the carbon black pigment dispersion.
The volume average particle diameter can be measured, for example, using a particle size analyzer (Nanotrack Wave-UT151, manufactured by Microtrack Bell Co., Ltd.).
The content of the resin is not particularly limited and can be appropriately selected according to the purpose. However, from the viewpoint of fixability and storage stability of the ink, the content is 1% by mass or more and 30% by mass based on the total amount of the ink. The following is preferable, and 5% by mass or more and 20% by mass or less is more preferable.
In the present invention, it is preferable to use an acrylic resin in order to improve blocking resistance. The acrylic resin content in the ink is preferably 3% by mass or more, more preferably 7% by mass or more. It is preferable that the content of the acrylic resin in the ink is 3% by mass or more because the anti-blocking property is further improved.

The particle size of the solid content in the ink is not particularly limited, and can be appropriately selected according to the purpose. From the viewpoint of improving image quality such as ejection stability and image density, the maximum frequency of the particle size of the solid content in the ink is preferably 20 nm or more and 1,000 nm or less, more preferably 20 nm or more and 150 nm or less, in terms of the maximum number. The solid content includes resin particles, pigment particles, and the like. The particle size can be measured using a particle size analyzer (Nanotrack Wave-UT151, manufactured by Microtrack Bell Co., Ltd.).

<Additive>
Surfactants, antifoaming agents, antiseptic and antifungal agents, antirust agents, pH adjusters, etc. may be added to the ink, if necessary.

<Surfactant>
Any of silicone surfactants, fluorine surfactants, amphoteric surfactants, nonionic surfactants, and anionic surfactants can be used as surfactants.
The silicone-based surfactant is not particularly limited and can be appropriately selected depending on the purpose. Among them, those that do not decompose even at high pH are preferred. Examples of silicone-based surfactants include side chain-modified polydimethylsiloxane, both-end-modified polydimethylsiloxane, single-end-modified polydimethylsiloxane, and side-chain both-end-modified polydimethylsiloxane. Those having a polyoxyethylene group or a polyoxyethylene-polyoxypropylene group as a modifying group are particularly preferred because they exhibit good properties as water-based surfactants. As the silicone-based surfactant, a polyether-modified silicone-based surfactant can also be used, and examples thereof include compounds in which a polyalkylene oxide structure is introduced into the side chain of the Si portion of dimethylsiloxane.
Examples of fluorine-based surfactants include perfluoroalkylsulfonic acid compounds, perfluoroalkylcarboxylic acid compounds, perfluoroalkylphosphoric acid ester compounds, perfluoroalkylethylene oxide adducts, and perfluoroalkyl ether groups in side chains. Polyoxyalkylene ether polymer compounds are particularly preferred due to their low foaming properties. Examples of perfluoroalkylsulfonic acid compounds include perfluoroalkylsulfonic acids and perfluoroalkylsulfonates. Examples of perfluoroalkylcarboxylic acid compounds include perfluoroalkylcarboxylic acids and perfluoroalkylcarboxylic acid salts. Examples of polyoxyalkylene ether polymer compounds having perfluoroalkyl ether groups in side chains include sulfuric acid ester salts of polyoxyalkylene ether polymers having perfluoroalkyl ether groups in side chains, and polyoxyalkylene ether polymers having perfluoroalkyl ether groups in side chains. Examples thereof include salts of oxyalkylene ether polymers. Counter ions _of salts _in these fluorosurfactants include Li, Na, _K , _NH4 , _NH3CH2CH2OH , _NH2 ( _CH2CH2OH ) _{2 ,} and NH( _CH2CH2OH ). ₃ and the like.
Amphoteric surfactants include, for example, laurylaminopropionate, lauryldimethylbetaine, stearyldimethylbetaine, lauryldihydroxyethylbetaine and the like.
Nonionic surfactants include, for example, polyoxyethylene alkylphenyl ethers, polyoxyethylene alkyl esters, polyoxyethylene alkylamines, polyoxyethylene alkylamides, polyoxyethylene propylene block polymers, sorbitan fatty acid esters, polyoxyethylene sorbitan Examples include fatty acid esters and ethylene oxide adducts of acetylene alcohol.
Examples of anionic surfactants include polyoxyethylene alkyl ether acetate, dodecylbenzene sulfonate, laurate, polyoxyethylene alkyl ether sulfate and the like.
These may be used individually by 1 type, and may use 2 or more types together.

The silicone-based surfactant is not particularly limited and can be appropriately selected depending on the intended purpose. Examples include terminal-modified polydimethylsiloxane, and polyether-modified silicone-based surfactants having polyoxyethylene groups or polyoxyethylene-polyoxypropylene groups as modifying groups are particularly preferred because they exhibit good properties as water-based surfactants.
As such a surfactant, an appropriately synthesized one may be used, or a commercially available product may be used. Commercially available products are available from, for example, BYK Chemie Co., Ltd., Shin-Etsu Chemical Co., Ltd., Dow Corning Toray Silicone Co., Ltd., Nihon Emulsion Co., Ltd., Kyoeisha Chemical Co., Ltd., and the like.
The above polyether-modified silicone-based surfactant is not particularly limited and can be appropriately selected according to the purpose. For example, a polyalkylene oxide structure represented by the following general formula (S-1) Examples include those introduced into the side chain of the Si portion of dimethylpolysiloxane.

（但し、前記一般式（Ｓ－１）式中、ｍ、ｎ、ａ、及びｂは、それぞれ独立に、整数を表し、Ｒは、アルキレン基を表し、Ｒ’は、アルキル基を表す。）

(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 above polyether-modified silicone-based surfactants. -1906EX (manufactured by Nippon Emulsion Co., Ltd.), FZ-2105, FZ-2118, FZ-2154, FZ-2161, FZ-2162, FZ-2163, FZ-2164 (manufactured by Dow Corning Toray Silicone Co., Ltd.), BYK -33, BYK-387 (manufactured by BYK-Chemie Co., Ltd.), TSF4440, TSF4452, TSF4453 (manufactured by Toshiba Silicon Co., Ltd.) and the like.

As the fluorosurfactant, a fluorine-substituted compound having 2 to 16 carbon atoms is preferable, and a fluorine-substituted compound having 4 to 16 carbon atoms is more preferable.
Examples of fluorine-based surfactants include perfluoroalkyl phosphate ester compounds, perfluoroalkyl ethylene oxide adducts, and polyoxyalkylene ether polymer compounds having perfluoroalkyl ether groups in side chains. Among these, a polyoxyalkylene ether polymer compound having a perfluoroalkyl ether group in a side chain is preferable because of its low foamability, and a fluorine-based compound represented by the following general formula (F-1) and general formula (F-2) Surfactants are more preferred.

上記一般式（Ｆ－１）で表される化合物において、水溶性を付与するためにｍは０～１０の整数が好ましく、ｎは０～４０の整数が好ましい。

In the compound represented by the 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.

上記一般式（Ｆ-２）で表される化合物において、ＹはＨ、又はＣ_ｍＦ_２ｍ＋１でｍは１～６の整数、又はＣＨ_２ＣＨ（ＯＨ）ＣＨ_２－Ｃ_ｍＦ_２ｍ＋１でｍは４～６の整数、又はＣ_ｐＨ_２ｐ＋１でｐは１～１９の整数である。ｎは１～６の整数である。ａは４～１４の整数である。

In the compound represented by the general formula (F-2), Y is H, or C _m F _2m+1 and m is an integer of 1 to 6, or CH ₂ CH(OH)CH ₂ —C _m F _2m+1 and m is an integer from 4 to 6, or C _p H _2p+1 where p is an integer from 1 to 19; n is an integer of 1-6. a is an integer from 4 to 14;

Commercially available products may be used as the fluorosurfactant. Examples of 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.); Fleurard FC-93, FC-95, FC-98, FC-129, FC-135, FC-170C, FC-430, FC-431 (both manufactured by Sumitomo 3M); Megafac F-470, F -1405, F-474 (both 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 Neos Co., Ltd.), 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 and FS-300 manufactured by Chemours Co., Ltd., which significantly improve good print quality, particularly color development, paper permeability, wettability, and level dyeing properties. FT-110, FT-250, FT-251, FT-400S, FT-150, FT-400SW manufactured by Neos, Polyfox PF-151N manufactured by Omnova and Unidyne DSN-403N manufactured by Daikin Industries, Ltd. are particularly preferred. .

The content of the surfactant in the ink is not particularly limited and can be appropriately selected according to the purpose. % or more and 5 mass % or less is preferable, and 0.05 mass % or more and 5 mass % or less is more preferable.

<Antifoaming agent>
The antifoaming agent is not particularly limited, and examples thereof include silicone antifoaming agents, polyether antifoaming agents, and fatty acid ester antifoaming agents. These may be used individually by 1 type, or may use 2 or more types together. Among these, silicone-based antifoaming agents are preferred because of their excellent foam breaking effect.

<Preservative and antifungal agent>
The antiseptic and antifungal agent is not particularly limited, and examples thereof include 1,2-benzisothiazolin-3-one.

<Antirust agent>
The rust inhibitor is not particularly limited, and examples thereof include acidic sulfites and sodium thiosulfate.

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

The physical properties of the ink are not particularly limited and can be appropriately selected depending on the intended purpose. For example, viscosity, surface tension, pH and the like 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, more preferably 5 mPa·s or more and 25 mPa·s or less, from the viewpoint of improving the print density and character quality and obtaining good ejection properties. more preferred. Here, for viscosity, for example, a rotational viscometer (RE-80L manufactured by Toki Sangyo Co., Ltd.) can be used. Measurement conditions are 25° C., standard cone rotor (1°34′×R24), sample liquid volume 1.2 mL, rotation speed 50 rpm, 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 that the ink is appropriately leveled on the recording medium and the drying time of the ink is shortened.
The pH of the ink is preferably from 7 to 12, more preferably from 8 to 11, from the viewpoint of preventing corrosion of metal members in contact with the liquid.

<Pretreatment liquid>
The pretreatment liquid contains a flocculant, an organic solvent, and water, and if necessary, may contain a surfactant, an antifoaming agent, a pH adjuster, an antiseptic antifungal agent, an antirust agent, and the like.
Organic solvents, surfactants, antifoaming agents, pH adjusters, antiseptic antifungal agents, and antirust agents can be the same materials as used for inks, and other materials used for known treatment liquids can be used. .
The type of flocculant is not particularly limited, and examples thereof include water-soluble cationic polymers, acids, and polyvalent metal salts.

<Post-treatment liquid>
The post-treatment liquid is not particularly limited as long as it can form a transparent layer. The post-treatment liquid is obtained by selecting and mixing organic solvents, water, resins, surfactants, antifoaming agents, pH adjusters, antiseptic antifungal agents, anticorrosive agents, etc., as necessary. The post-treatment liquid may be applied to the entire recording area formed on the recording medium, or may be applied only to the area where the ink image is formed.

<Recording medium>
A recording medium used for recording is not particularly limited, but examples thereof include plain paper, glossy paper, special paper, cloth, film, OHP sheet, and general-purpose printing paper.

The recording medium is not limited to those used as general recording media, and wallpaper, floor materials, building materials such as tiles, cloth for clothing such as T-shirts, textiles, leather, and the like can be used as appropriate. Ceramics, glass, metal, etc. can also be used by adjusting the configuration of the path for conveying the recording medium.

<Records>
The ink recorded matter relating to the present invention has an image formed on a recording medium using the ink in the set of the ink and cleaning liquid of the present invention.
A recorded matter can be obtained by recording with an inkjet recording apparatus and an inkjet recording method.

<Washing liquid>
The cleaning liquid contains water and an organic solvent, and further contains other components as necessary.

<<Organic solvent>>
As the organic solvent in the cleaning liquid, it is preferable to contain 10% by mass or more of an organic solvent having a hydrogen bond term of 4.5 or less in the Hansen solubility parameter (HSP), and more preferably 15% by mass or more and 40% by mass or less. preferable. By including a large amount of organic solvent with a low HSP value, it becomes easier to swell the dried ink.
Examples of organic solvents having a Hansen solubility parameter (HSP) hydrogen bond term of 4.5 or less include diethylene glycol diethyl ether (δH of HSP: 2.73 (cal/cm ³ ) ^1/2 ), 2-pyrrolidone ( δH of HSP: 4.39 (cal/cm ³ ) ^1/2 ), propylene glycol monobutyl ether (δH of HSP: 4.48 (cal/cm ³ ) ^1/2 ), diethylene glycol monobutyl ether (δH of HSP: 2 .14 (cal/cm ³ ) ^1/2 ), propylene glycol monopropyl ether (δH of HSP: 4.48 (cal/cm ³ ) ^1/2 ), and the like.

[Hansen Solubility Parameter Hydrogen Bond Term]
The hydrogen bond term (hereinafter sometimes referred to as "δH") of the Hansen solubility parameter (hereinafter sometimes referred to as "HSP") of an organic solvent is 7.0 (cal/cm ³ ) ^1/2 or less. and preferably 5.0 (cal/cm ³ ) ^1/2 or more and 6.8 (cal/cm ³ ) ^1/2 or less. When the hydrogen bond term of the Hansen solubility parameter is 7.0 (cal/cm ³ ) ^1/2 or less, detergency can be improved, and more excellent ejection reliability can be obtained.

The Hansen solubility parameter (HSP) divides the solubility parameter (SP) introduced by Hildebrand into three components: the dispersion term (δD), the polar term (δP), and the hydrogen bonding term (δH). , in three-dimensional space. The dispersion term (δD) is a term based on the Van Der Waals proximity force. The polarity term (δP) is also called a polarization term and is a term caused by dipole moment, dielectric constant, and the like. The hydrogen bond term (δH) includes intermolecular forces based on hydrogen bonds and π-π interactions that cannot be classified elsewhere. This hydrogen bond term (δH) is used in the present invention.
The three components of the dispersion term (δD), the polar term (δP), and the hydrogen bond term (δH) have been sought by Hansen and his successors, and are described in the Polymer Handbook (fourth edition), VII-698-711 describes in detail. In addition, the definition and calculation of HSP are described in the following references. Charles M. Hansen, Hansen Solubility Parameters: A Users Handbook (CRC Press, 2007).
Hansen Solubility Parameter values have been investigated for many solvents and resins, see, for example, Wesley L. et al. Archer, Industrial Splvents Handbook.

The organic solvent is not particularly limited as long as the hydrogen bond term of the Hansen solubility parameter can be adjusted, and can be appropriately selected depending on the purpose. Organic solvents are preferable, and water-soluble organic solvents are more preferable. In addition, water solubility means dissolving 5g or more in 100g of water of 25 degreeC, for example.
Examples of the water-soluble organic solvent include polyhydric alcohols, ethers such as polyhydric alcohol alkyl ethers and polyhydric alcohol aryl ethers, nitrogen-containing heterocyclic compounds, amides, amines, sulfur-containing compounds, Propylene carbonate (δH of HSP: 2.00 (cal/cm ³ ) ^1/2 ), ethylene carbonate (δH of HSP: 2.49 (cal/cm ³ ) ^1/2 ), and the like.

Examples of the polyhydric alcohols include ethylene glycol (δH of HSP: 12.7 (cal/cm ³ ) ^1/2 ) and diethylene glycol (δH of HSP: 9.27 (cal/cm ³ ) ^1/2 ). , 1,2-propanediol (δH of HSP: 3.31 (cal/cm ³ ) ^1/2 ), 1,3-propanediol (δH of HSP: 11.3 (cal/cm ³ ) ^1/2 , specific gravity: 1.005), 1,2-butanediol (δH of HSP: 10.2 (cal/cm ³ ) ^1/2 , specific gravity: 1.002), 1,3-butanediol (δH of HSP: 9 .37 (cal/cm ³ ) ^1/2 , specific gravity: 1.005), 1,4-butanediol (δH of HSP: 10.2 (cal/cm ³ ) ^1/2 ), 3-methyl-1, 3-butanediol (δH of HSP: 8.19 (cal/cm ³ ) ^1/2 ), 2,3-butanediol (δH of HSP: 8.19 (cal/cm ³ ) ^1/2 ), triethylene Glycol (δH of HSP: 9.07 (cal/cm ³ ) ^1/2 ), 1,5-pentanediol (δH of HSP: 9.65 (cal/cm ³ ) ^1/2 ), 1,6-hexane diol (δH of HSP: 8.68 (cal/cm ³ ) ^1/2 ), glycerin (δH of HSP: 13.3 (cal/cm ³ ) ^1/2 ), 3-methoxy-3-methyl-1- butanol (δH of HSP: 6.29 (cal/cm ³ ) ^1/2 , specific gravity: 0.927), 3-ethyl-3-oxacenemethanol (δH of HSP: 6.05 (cal/cm ³ ) ^{1 /2} , specific gravity: 1.019). These may be used individually by 1 type, and may use 2 or more types together.

Examples of the polyhydric alcohol alkyl ethers include ethylene glycol monoethyl ether (δH of HSP: 6.83 (cal/cm ³ ) ^1/2 ), ethylene glycol monobutyl ether (δH of HSP: 6.00 (cal /cm ³ ) ^1/2 ), diethylene glycol monomethyl ether (δH of HSP: 6.14 (cal/cm ³ ) ^1/2 ), diethylene glycol monoethyl ether (δH of HSP: 5.95 (cal/cm ³ ) ^{1 /2} ), diethylene glycol diethyl ether (δH of HSP: 2.73 (cal/cm ³ ) ^1/2 ), diethylene glycol monobutyl ether (δH of HSP: 5.17 (cal/cm ³ ) ^1/2 ), propylene glycol monoethyl ether (δH of HSP: 5.12 (cal/cm ³ ) ^1/2 ), propylene glycol monopropyl ether (δH of HSP: 4.48 (cal/cm ³ ) ^1/2 ), propylene glycol monobutyl ether (δH of HSP: 4.48 (cal/cm ³ ) ^1/2 ), propylene glycol monoisobutyl ether (δH of HSP: 4.78 (cal/cm ³ ) ^1/2 ), diethylene glycol dibutyl ether (δH of HSP : 2.14 (cal/cm ³ ) ^1/2 ), dipropylene glycol mono-n-butyl ether (δH of HSP: 4.87 (cal/cm ³ ) ^1/2 ), and the like. These may be used individually by 1 type, and may use 2 or more types together.

Examples of the polyhydric alcohol aryl ethers include ethylene glycol monophenyl ether and ethylene glycol monobenzyl ether.
Examples of the nitrogen-containing heterocyclic compound include 2-pyrrolidone (δH of HSP: 4.39 (cal/cm ³ ) ^1/2 , specific gravity: 1.1), N-methyl-2-pyrrolidone (δH of HSP : 3.51 (cal/cm ³ ) ^1/2 ), ε-caprolactam (δH of HSP: 1.90 (cal/cm ³ ) ^1/2 ), and the like. These may be used individually by 1 type, and may use 2 or more types together.
Examples of the amides include formamide (δH of HSP: 9.27 (cal/cm ³ ) ^1/2 ), N-methylformamide (δH of HSP: 7.76 (cal/cm ³ ) ^1/2 ). , N,N-dimethylformamide (δH of HSP: 5.51 (cal/cm ³ ) ^1/2 ). These may be used individually by 1 type, and may use 2 or more types together.
Examples of the amines include monoethanolamine (δH of HSP: 10.2 (cal/cm ³ ) ^1/2 ), diethanolamine (δH of HSP: 9.67 (cal/cm ³ ) ^1/2 ), and the like. is mentioned. These may be used individually by 1 type, and may use 2 or more types together.
Examples of the sulfur-containing compounds include dimethyl sulfoxide (δH of HSP: 4.98 (cal/cm ³ ) ^1/2 ) and sulfolane (δH of HSP: 4.24 (cal/cm ³ ) ^1/2 ). etc. These may be used individually by 1 type, and may use 2 or more types together.

Among these, solvents having a hydrogen bond term of the Hansen solubility parameter of 5 (cal/cm ³ ) ^1/2 or less are preferable, and dipropylene glycol mono-n-butyl ether (δH of HSP: 4.87 (cal/cm ³ ) ^1/2 ), 2-pyrrolidone (δH of HSP: 4.39 (cal/cm ³ ) ^1/2 ), diethylene glycol diethyl ether (δH of HSP: 2.73 (cal/cm ³ ) ^1/2 ), Propylene glycol monobutyl ether (δH of HSP: 4.48 (cal/cm ³ ) ^1/2 ), diethylene glycol dibutyl ether (δH of HSP: 2.14 (cal/cm ³ ) ^1/2 ), propylene glycol monoisobutyl ether (δH of HSP: 4.78 (cal/cm ³ ) ^1/2 ), propylene glycol monopropyl ether (δH of HSP: 4.48 (cal/cm ³ ) ^1/2 ), by the following general formula (1) (R ¹ represents a methyl group, δH: 4.63 (cal/cm ³ ) ^1/2 , specific gravity: 0.99), a compound represented by the following general formula (1) (R ¹ represents representing an ethyl group, δH: 3.65 (cal/cm ³ ) ^1/2 , specific gravity: 0.97), a compound represented by the following general formula (1) (R ¹ represents a butyl group, δH: 3 .26 (cal/cm ³ ) ^1/2 ) is more preferable, and a compound represented by the following general formula (1) (R ¹ represents a methyl group, δH: 4.63 (cal/cm ³ ) ^1/2 ), and compounds represented by the following general formula (1) (R ¹ represents an ethyl group, δH: 3.65 (cal/cm ³ ) ^1/2 ) are particularly preferred.

ただし、前記一般式（１）中、Ｒ^１は、炭素数１以上４以下のアルキル基を表す

However, in the general formula (1), R ¹ represents an alkyl group having 1 to 4 carbon atoms

The HSP value (Hansen solubility parameter hydrogen bond term) of the organic solvent is determined by Charles M. et al. It can also be determined using the software HSPiP from Hansen Consulting (Horsholm, Denmark, hansen-solubility.com). The following describes how to determine the hydrogen-bonding term of the Hansen solubility parameter using HSPiP software in a solvent for which the hydrogen-bonding term of the Hansen solubility parameter is unknown.
As of October 2015, http://www. pirika. It can be determined using HSPiP version 4.1 software, available from com/.

The hydrogen-bonding term of the Hansen Solubility Parameter for the solvent can be determined from the chemical structure (backbone, functional groups) using the modified SMILES notation using the HSP prediction tool in HSPiP. In the present invention, the values for solvents registered in the database of HSPiP version 3.0.38 (see various HSP literature) are used, and the values estimated by the HSPiP for solvents not in the database are used. use.
The content of the organic solvent is preferably 60% by mass or more, more preferably 70% by mass or more and 80% by mass or less, relative to the total amount of the cleaning liquid.

-water-
The water is not particularly limited and can be appropriately selected depending on the intended purpose. These may be used individually by 1 type, and may use 2 or more types together.
The content of water is not particularly limited and can be appropriately selected according to the purpose, but is preferably 10% by mass or more and 30% by mass or less, more preferably 10% by mass or more and 20% by mass or less.

<<Other Ingredients>>
Other components include, for example, surfactants, antifoaming agents, antiseptic and antifungal agents, antirust agents, and pH adjusters.

-Surfactant-
The surfactant is not particularly limited and can be appropriately selected depending on the intended purpose. For example, fluorine-based surfactants are preferred, and 2-perfluoroalkylethanol is more preferred.
As the surfactant, an appropriately synthesized one may be used, or a commercially available product may be used. Examples of the commercially available products include Zonyl (registered trademark) FSO-100 (manufactured by DuPont).

- Defoamer -
The antifoaming agent is not particularly limited and can be appropriately selected depending on the intended purpose. Examples thereof include 2,4,7,9-tetramethyl-4,7-decanediol.

<Washing method and washing device>
The cleaning method of the present invention is a cleaning method for cleaning the nozzle surface of an ink ejection head, and includes a step of applying a cleaning liquid to a wiping member (hereinafter sometimes referred to as a "cleaning liquid applying step"), and a step of applying the cleaning liquid. a step of wiping the nozzle surface with a wiping member (hereinafter sometimes referred to as a “wiping step”), and further includes other steps as necessary.
The cleaning method of the present invention is a cleaning method for cleaning the nozzle surface of an ink ejection head using the cleaning liquid in the ink and cleaning liquid set of the present invention,
a step of applying the cleaning liquid to the nozzle surface (hereinafter sometimes referred to as a "cleaning liquid applying step"); and a step of wiping the nozzle surface to which the cleaning liquid has been applied with a wiping member (hereinafter referred to as a "wiping step"). and , and further include other steps as necessary.
The cleaning liquid is the cleaning liquid in the ink and cleaning liquid set of the present invention.

A cleaning device according to the present invention is a cleaning device for cleaning the nozzle surface of an ink discharge head, and includes means for applying cleaning liquid to a wiping member (hereinafter sometimes referred to as "cleaning liquid applying means") and means for wiping the nozzle surface with a wiping member (hereinafter sometimes referred to as "wiping means"), and other means if necessary.
A cleaning apparatus of the present invention is a cleaning apparatus for cleaning a nozzle surface of an ink ejection head using the cleaning liquid in the ink and cleaning liquid set of the present invention,
Means for applying the cleaning liquid to the nozzle surface (hereinafter sometimes referred to as "cleaning liquid applying means") and means for wiping the nozzle surface to which the cleaning liquid is applied with a wiping member (hereinafter referred to as "wiping means") and, if necessary, other means.
The cleaning liquid is the cleaning liquid in the ink and cleaning liquid set of the present invention.

<<Cleaning liquid applying step and cleaning liquid applying means>>
The wiping member is usually provided on a pressing member, and the pressing member is not particularly limited as long as it can press the nozzle surface via the wiping member, and can be appropriately selected according to the purpose. For example, a pressure roller, a combination of pressure roller and pressure belt, a wiper, a blade, and the like. Among these, a pressing roller is preferable.
It should be noted that the head and the wiping member may be brought into contact with each other and wiped by moving the head up and down or back and forth with respect to the fixed wiping member.
The cleaning liquid application means is not particularly limited as long as it can apply a certain amount of cleaning liquid to the wiping member or nozzle surface, and can be appropriately selected according to the purpose. A coating device and the like are included.
The wiping member is not particularly limited and can be appropriately selected according to the purpose. Examples thereof include nonwoven fabric and cloth. These are preferably wound in a roll shape, and a roll-shaped nonwoven fabric is preferable from the viewpoint of less dust generation and high reliability.

It is preferable that the application amount of the cleaning liquid is controlled by the recording time. In this case, it is more preferable that the application amount of the cleaning liquid is selected from a plurality of set values. Examples of the plurality of setting values include methods of applying the cleaning liquid (for example, "pressure", "number of application times", and "number of application nozzles").
It is preferable that the amount of the cleaning liquid to be applied is controlled by a pressure applied to a cleaning liquid applying nozzle as a cleaning liquid applying means. Further, when the cleaning liquid is applied from a plurality of cleaning liquid applying nozzles, it is preferable that the amount of the cleaning liquid applied to the wiping member or the nozzle surface is controlled by the number of the cleaning liquid applying nozzles. Further, it is preferable that the amount of the cleaning liquid applied to the wiping member or the nozzle surface is controlled by the number of times the cleaning liquid is applied from the cleaning liquid applying nozzle.

<<Wiping Step and Wiping Means>>
The wiping step is a step of wiping the nozzle surface with a wiping member to which the cleaning liquid is applied, or wiping the nozzle surface to which the cleaning liquid is applied with the wiping member, and is preferably carried out by the wiping means.
The method of wiping the nozzle surface with the wiping member to which the cleaning liquid is applied is not particularly limited and can be appropriately selected according to the purpose. A method of wiping the nozzle surface and the like can be mentioned.
The method of wiping the nozzle surface to which the cleaning liquid is applied with the wiping member is not particularly limited and can be appropriately selected according to the purpose. and a method of wiping with a nonwoven fabric.

<<Other steps and other means>>
Examples of the other process and the other means include a control process and control means.
Examples of the control means include devices such as sequencers and computers.

Here, FIG. 1 is a schematic diagram showing an example of an ink ejection head cleaning apparatus according to the present invention. The cleaning device 300 shown in FIG. 1 is a device for cleaning a nozzle surface 301a on the ink ejection side of a nozzle plate 301 of an ink ejection head.
The cleaning device 300 includes a nonwoven fabric 303 as a wiping member, a cleaning liquid applying nozzle 302 as a cleaning liquid applying means, a pressing roller 305 as a pressing member, and a winding roller 304 for winding up the nonwoven fabric after the wiping process. there is
The cleaning liquid is supplied from the cleaning liquid tank through a cleaning liquid supply tube (not shown). By driving a pump provided in the cleaning liquid supply tube, the cleaning liquid is applied from the cleaning liquid applying nozzle 302 to the nonwoven fabric 303 as the wiping member in an amount of cleaning liquid depending on the recording time. Note that the nonwoven fabric 303 is wound into a roll.
Then, as shown in FIG. 1, the nozzle surface 301a of the nozzle plate 301 is cleaned by the nonwoven fabric 303 applied with the cleaning liquid being pressed against the nozzle surface 301a of the nozzle plate 301 by a pressing roller 305 as a pressing member. After the wiping process is finished, the nonwoven fabric 303 is taken up by the take-up roller 304 .
A plurality of cleaning liquid deposition nozzles 302 can be provided as cleaning liquid deposition means, and pressure can be applied based on control by a control means (not shown). By appropriately changing the pressure, the amount of cleaning liquid deposited can be controlled. can be adjusted. Also, the amount of cleaning liquid to be applied can be adjusted by changing the number of nozzles that apply cleaning liquid based on the control of a control means (not shown). Furthermore, the application amount of the cleaning liquid can be adjusted by changing the number of times the cleaning liquid is applied under the control of the control means (not shown).

<Inkjet printing apparatus and inkjet printing method>
The inkjet printing apparatus of the present invention comprises a set of the ink of the present invention and a cleaning liquid, a recording head for printing by ejecting the ink in the set of the ink and the cleaning liquid, and ink remaining in the ink flow path or the recording head as the ink. a cleaning means for cleaning with the cleaning liquid in the cleaning liquid set, and further comprising other means as necessary.
The inkjet printing method of the present invention comprises a printing step of printing by ejecting the ink in the set of the ink and the cleaning liquid of the present invention, and cleaning the ink remaining in the ink flow path or the recording head with the cleaning liquid in the set of the ink and the cleaning liquid. washing step, and optionally other steps.

The ink in the set of the ink and the cleaning liquid of the present invention can be suitably used for various recording apparatuses using an inkjet recording system, such as printers, facsimile machines, copiers, printer/facsimile/copier complex machines, stereolithography machines, and the like. .
In the present invention, a recording apparatus and a recording method refer to an apparatus capable of ejecting ink, various treatment liquids, and the like onto a recording medium, and a method of performing recording using the apparatus. A recording medium means a medium to which ink or various processing liquids can adhere even temporarily.
This recording apparatus can include not only a head portion for ejecting ink, but also means for feeding, conveying, and discharging a recording medium, and other devices called pre-processing devices and post-processing devices. .
The inkjet printing apparatus and the inkjet printing method may have heating means used in the heating process and drying means used in the drying process. The heating means and drying means include, for example, means for heating and drying the printing surface and the back surface of the recording medium. The heating means and the drying means are not particularly limited, but for example, hot air heaters and infrared heaters can be used. Heating and drying can be performed before, during, or after printing.
Moreover, the inkjet printing apparatus and the inkjet printing method are not limited to those in which significant images such as characters and figures are visualized by ink. For example, it includes those that form patterns such as geometric patterns, and those that form three-dimensional images.
Unless otherwise specified, the inkjet printing apparatus includes both a serial type apparatus in which the ejection head is moved and a line type apparatus in which the ejection head is not moved.
Furthermore, this inkjet printing apparatus is not only a desktop type, but also a wide inkjet printing apparatus capable of printing on A0 size recording media, and for example, a roll of continuous paper is used as a recording medium. Also included is a continuous feed printer capable of

An example of an inkjet printing apparatus will be described with reference to FIGS. 2 and 3. FIG. FIG. 2 is a perspective explanatory view of the device. FIG. 3 is a perspective explanatory view of the main tank. An image forming apparatus 400 as an example of an inkjet printing apparatus is a serial image forming apparatus. A mechanical unit 420 is provided inside the exterior 401 of the image forming apparatus 400 . Each ink container 411 of the main tank 410 (410k, 410c, 410m, 410y) for each color of black (K), cyan (C), magenta (M), and yellow (Y) is made of, for example, an aluminum laminated film. It is formed by a packaging member. The ink containing portion 411 is contained, for example, in a container case 414 made of plastic. Thus, the main tank 410 is used as an ink cartridge for each color.
On the other hand, a cartridge holder 404 is provided on the far side of the opening when the cover 401c of the apparatus main body is opened. A main tank 410 is detachably attached to the cartridge holder 404 . As a result, each ink discharge port 413 of the main tank 410 communicates with the ejection head 434 for each color via the supply tube 436 for each color, and ink can be ejected from the ejection head 434 onto the printing medium.

This inkjet printing apparatus can include not only a portion that ejects ink, but also devices called pre-processing devices and post-processing devices.
As an aspect of the pre-treatment device and the post-treatment device, it has a pre-treatment liquid and a post-treatment liquid in the same manner as in the case of inks such as black (K), cyan (C), magenta (M), and yellow (Y). There is a mode in which a liquid container and a liquid ejection head are added, and the pretreatment liquid and the posttreatment liquid are ejected by an inkjet recording method.
As another aspect of the pre-treatment device and the post-treatment device, there is an aspect in which a pre-treatment device and a post-treatment device using a method other than the inkjet recording method, such as a blade coating method, a roll coating method, and a spray coating method, are provided.

The use of the ink in the set of the ink and the cleaning liquid of the present invention is not particularly limited, and can be appropriately selected according to the purpose. . Furthermore, it can be used not only as an ink to form two-dimensional characters and images, but also as a three-dimensional modeling material for forming a three-dimensional three-dimensional image (three-dimensional object).
A known three-dimensional modeling apparatus for forming three-dimensional objects can be used, and is not particularly limited. be able to. The three-dimensional object includes a three-dimensional object obtained by applying ink repeatedly. It also includes a molded product obtained by processing a structure obtained by applying ink onto a base material such as a recording medium. Molded processed products are, for example, products obtained by subjecting recorded matter or structures formed in the form of sheets or films to molding processes such as heat stretching and punching. It is suitable for use in applications where the surface is molded after decoration, such as electronic devices, meters of cameras, etc., and operation panel panels.

In the present invention, the terms image formation, recording, printing, and printing are all synonymous.

The terms recording medium, medium, and printed material are all synonymous.

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

(Preparation Example 1)
- Preparation of pigment dispersion -
After the inside of a 1 L flask equipped with a mechanical stirrer, a thermometer, a nitrogen gas inlet tube, a reflux tube and a dropping funnel was sufficiently replaced with nitrogen gas, 11.2 g of styrene, 2.8 g of acrylic acid and 12 g of lauryl methacrylate were added. 0 g, 4.0 g of polyethylene glycol methacrylate, 4.0 g of styrene macromer, and 0.4 g of mercaptoethanol were mixed and heated to 65°C.
Next, styrene 100.8 g, acrylic acid 25.2 g, lauryl methacrylate 108.0 g, polyethylene glycol methacrylate 36.0 g, hydroxylethyl methacrylate 60.0 g, styrene macromer 36.0 g, mercaptoethanol 3.6 g, azobismethyl valero. A mixed solution of 2.4 g of nitrile and 18 g of methyl ethyl ketone was dropped into the flask over 2.5 hours. After dropping, a mixed solution of 0.8 g of azobismethylvaleronitrile and 18 g of methyl ethyl ketone was dropped into the flask over 0.5 hours. After aging at 65° C. for 1 hour, 0.8 g of azobismethylvaleronitrile was added and further aged for 1 hour. After completion of the reaction, 364 g of methyl ethyl ketone was added into the flask to obtain 800 g of polymer solution A having a concentration of 50% by mass.
Next, 28 g of the obtained polymer solution A, C.I. I. 42 g of carbon black (FW100 manufactured by Degussa), 13.6 g of 1 mol/L potassium hydroxide aqueous solution, 20 g of methyl ethyl ketone, and 13.6 g of deionized water were sufficiently stirred and then kneaded using a roll mill.
The obtained paste was poured into 200 g of pure water and stirred sufficiently, and methyl ethyl ketone and water were distilled off using an evaporator. Pressure filtration was performed with a membrane filter to obtain a carbon black pigment-containing polymer fine particle dispersion having a pigment solid content of 15% by mass and a solid content concentration of 20% by mass.
The volume average particle diameter of the polymer fine particles in the carbon black pigment-containing polymer fine particle dispersion was measured with a particle size distribution analyzer (manufactured by Nikkiso Co., Ltd., Nanotrac UPA-EX150) and found to be 104 nm.

(Ink Production Examples 1 to 6)
-Preparation of inks 1 to 6-
1,3-Butanediol, 1,2-propanediol, and Surfactant A (Unidyne DSN-403, manufactured by Daikin Industries, Ltd.) in the amounts shown in Table 1 were placed in a container equipped with a stirrer and stirred for 30 minutes. Stir to homogenize.
Next, the pigment dispersion of Preparation Example 1 having the pigment solid content shown in Table 1 and high-purity water were added and stirred for about 60 minutes to homogenize. Further, a resin having a solid content shown in Table 1 was added, and the mixture was stirred for 30 minutes to homogenize the ink.
The obtained inks were pressure-filtered through a polyvinylidene fluoride membrane filter having an average pore size of 1.2 μm to remove coarse particles and dust to prepare inks 1 to 6.

Next, the "Tg of dried ink" was measured as follows for the obtained ink. Table 1 shows the results.

<Glass transition temperature (Tg) of dry ink>
5 g of ink was dropped on a Teflon (registered trademark) Petri dish with a diameter of 4 cm and dried in an environment of 50° C. for 72 hours to obtain a dried ink product.
The resulting dried ink was measured using a differential scanning calorimeter (Thermo plus EVO2 DSC8231, manufactured by Rigaku Corporation) to calculate the glass transition temperature (Tg).

＊表１中の顔料分散体及び樹脂の配合量（質量％）は、固形分で表される。

*The compounding amounts (% by mass) of the pigment dispersion and the resin in Table 1 are expressed in terms of solid content.

Detailed contents of each component in Table 1 are as follows.
-resin-
・ Urethane resin 1: Superflex 150 (manufactured by Daiichi Kogyo Seiyaku Co., Ltd.), glass transition temperature (Tg) = 40 ° C.
・ Acrylic resin 1: Movinyl 6899D (manufactured by Nippon Synthetic Chemical Co., Ltd.), glass transition temperature (Tg) = 49 ° C.
・ Acrylic resin 2: Movinyl 6969D (manufactured by Nippon Synthetic Chemical Co., Ltd.), glass transition temperature (Tg) = 71 ° C.
・ Acrylic resin 3: Acryt 3MF-320 (manufactured by Taisei Fine Chemical Co., Ltd.), glass transition temperature (Tg) = 85 ° C.
・ Acrylic resin 4: Movinyl 972 (manufactured by Nippon Synthetic Chemical Co., Ltd.), glass transition temperature (Tg) = 101 ° C.
The glass transition temperature of each resin was measured in the same manner as the glass transition temperature (Tg) of the dried ink.
-Organic solvent-
・ 1,3-butanediol (manufactured by Tokyo Chemical Industry Co., Ltd.)
・ 1,2-propanediol (manufactured by Tokyo Chemical Industry Co., Ltd.)
-Surfactant-
・Surfactant A: Unidyne DSN-403 (manufactured by Daikin Industries, Ltd.)

(Production Examples 1 to 4 of cleaning solution)
- Preparation of washing solutions 1 to 4 -
In a container equipped with a stirrer, the amounts shown in Table 2 of 3-methyl-1,3-butanediol, N,N-dimethylformamide, diethylene glycol diethyl ether, and surfactant B (Zonyl FSO-100 (manufactured by DuPont )) and stirred for 30 minutes to homogenize.
Next, the remaining amount of highly pure water was added so that the total amount was 100% by mass, and the mixture was stirred for 60 minutes and homogenized to obtain cleaning liquids 1 to 4.

Detailed contents of each component in Table 2 are as follows.
・3-methyl-1,3-butanediol (manufactured by Tokyo Chemical Industry Co., Ltd., HSP δH: 8.19 (cal/cm ³ ) ^1/2 ))
・N,N-dimethylformamide (manufactured by Tokyo Chemical Industry Co., Ltd., δH of HSP: 5.51 (cal/cm ³ ) ^1/2 ))
・Diethylene glycol diethyl ether (manufactured by Tokyo Chemical Industry Co., Ltd., HSP δH: 2.73 (cal/cm ³ ) ^1/2 ))
The hydrogen bond term of the Hansen solubility parameter of the organic solvent was determined from the chemical structure (main chain, functional group) using the improved SMILES notation using the HSP prediction tool in HSPiP. In the present invention, the values for solvents registered in the database of HSPiP version 3.0.38 (see various HSP literature) are used, and the values estimated by the HSPiP for solvents not in the database are used. used.
・Surfactant B: Zonyl FSO-100 (manufactured by DuPont)

(Examples 1 to 5 and Comparative Examples 1 to 3)
Next, inks and cleaning liquids were combined as shown in Tables 3 and 4 below to form ink and cleaning liquid sets of Examples 1 to 5 and Comparative Examples 1 to 3.
Next, using the sets of the ink and cleaning liquid of Examples 1 to 5 and Comparative Examples 1 to 3, various characteristics were evaluated as follows. The results are shown in Tables 3 and 4.

<Swelling rate>
5 g of ink was dropped on a petri dish of Teflon (registered trademark) with a diameter of 4 cm, and dried in an environment of 50° C. for 72 hours to obtain a dried ink film.
A 1-cm square piece was cut out from the dried ink film, and the mass of the piece was measured. Soak the cut-out ink film in a sufficient amount of cleaning liquid, leave it at room temperature (25°C) for 3 minutes, remove it from the cleaning liquid, and wipe it with a Kimwipe (manufactured by Nippon Paper Crecia Co., Ltd.) so that the cleaning liquid adhering to the surface cannot be visually confirmed. ), the mass was measured, and the swelling rate was calculated from the following formula 1.
Swelling rate (%) = 100 × [(B - A) / A] ... Equation 1
However, in Equation 1, A represents the mass of the ink film before immersion, and B represents the mass of the ink film after immersion.

<Washability>
A SUS316 plate (3 cm×4 cm) was immersed in each ink and cleaning solution set for 60 minutes. After that, the plate was dried by standing at room temperature (25° C.) for 2 hours under a pressurized condition of 0.1 MPa in the atmosphere to obtain a SUS316 plate to which the dried ink was adhered.
The resulting SUS316 plate with the dried ink adhered thereto was repeatedly spray-washed for 3 minutes using 30 mL of the cleaning liquid in each set of ink and cleaning liquid. After completion of spray washing, the SUS316 plate was visually observed, and "washability" was evaluated based on the following evaluation criteria.
[Evaluation criteria]
◎: In the initial stage of repeated spray washing (within 1 minute), no dried ink could be observed. ○: After repeated spray washing, no dried ink could be observed. ×: No change was observed in the dried ink before and after washing.

<Ejection stability>
Using an inkjet printer (device name: IPSiO GX e3300, manufactured by Ricoh Co., Ltd.), each ink and cleaning liquid set was continuously discharged for 45 minutes, and the surface of the recording head was dried for 30 minutes after the discharge was stopped. After that, 3 mL of cleaning liquid was applied to the nozzle surface of the recording head using a dropper, wiping was performed, and ink was ejected again, and "ejection stability" was evaluated based on the following evaluation criteria.
[Evaluation criteria]
⊚: No discharge disturbance or discharge failure at all ○: Discharge disturbance or discharge failure for 5 nozzles or less ×: Discharge disturbance or discharge failure for more than 5 nozzles

<Blocking resistance>
The blocking resistance was evaluated with reference to the TAPPI T477 test method published by the Japan Pulp and Paper Institute.
Using an inkjet printer (device name: IPSiO GX e3300, manufactured by Ricoh Co., Ltd.) on gloss paper for printing (LumiArtGross with a basis weight of 90 g / m ² , manufactured by Store Enso), each ink and cleaning liquid set is printed 6 cm. After printing a solid image on all four sides with an ink adhesion amount of 10,000 mg/m ² , unprinted gloss paper for printing was superimposed on the printing surface of the solid image, and this was sandwiched between two glass plates of 10 cm square, A load of 1 kg/m ² was applied from above and left under environmental conditions of 40° C. and 90% RH for 24 hours. After that, it was left at room temperature (25° C.) for 2 hours, and when the glossy printing papers were peeled off, the degree of sticking to each other was visually observed, and the “blocking resistance” was evaluated based on the following evaluation criteria.
[Evaluation criteria]
◎: No blocking (no tackiness or adhesion occurs on the adjacent surface, and the surface of the sample is not damaged)
○: No blocking (adhesion or adhesion occurs slightly on the adjacent surface, but the surface of the sample is not damaged)
△: Slightly blocked (Slightly sticky. Slight scratches on the surface of the sample)
×: Significant blocking (adhesion or adhesion occurs on the adjacent surface. Scratches on the surface of the sample)

Embodiments of the present invention are, for example, as follows.
<1> an ink containing a coloring material and a resin;
a cleaning liquid containing water and an organic solvent;
the glass transition temperature of the ink in a dry state is 40° C. or higher and 90° C. or lower;
A set of the ink and the cleaning liquid, wherein the swelling rate calculated based on the following formula 1 is 10% or more from the mass of the ink film obtained by drying the ink before and after being immersed in the cleaning liquid.
Swelling rate (%) = 100 × [(B - A) / A] ... Equation 1
However, in Equation 1, A represents the mass of the ink film before immersion, and B represents the mass of the ink film after immersion.
<2> A set of the ink and cleaning liquid according to <1>, wherein the swelling rate is 14% or more.
<3> A set of the ink and cleaning liquid according to any one of <1> to <2>, wherein the resin in the ink has a glass transition temperature of 60° C. or higher.
<4> The ink and cleaning liquid set according to any one of <1> to <3>, wherein the resin is at least one of acrylic resin and urethane resin.
<5> The ink and cleaning liquid set according to any one of <1> to <4>, wherein the content of the resin in the ink is 1% by mass or more and 30% by mass or less.
<6> the resin in the ink is an acrylic resin;
A set of the ink and cleaning liquid according to any one of <1> to <5>, wherein the content of the acrylic resin in the ink is 3% by mass or more.
<7> A set of the ink and cleaning liquid according to any one of <1> to <6>, wherein the ink contains an organic solvent.
<8> A set of the ink and cleaning liquid according to any one of <1> to <7>, wherein the ink contains a fluorosurfactant.
<9> Any one of <1> to <8>, wherein the organic solvent in the cleaning liquid contains 10% by mass or more of an organic solvent having a hydrogen bond term of 4.5 or less in the Hansen solubility parameter (HSP). It is a set of described ink and cleaning liquid.
<10> The above <1> to <9>, wherein the organic solvent in the cleaning solution is at least one selected from 3-methyl-1,3-butanediol, N,N-dimethylformamide, and diethylene glycol diethyl ether. 3. A set of the ink and the cleaning liquid according to any one of .
<11> The ink and cleaning liquid set according to any one of <1> to <10>, wherein the cleaning liquid contains a fluorosurfactant.
<12> A set of the ink and cleaning liquid according to any one of <1> to <11>;
a recording head for printing by ejecting the ink in the ink and cleaning liquid set;
cleaning means for cleaning ink remaining in the ink channel or the recording head with the cleaning liquid in the set of the ink and the cleaning liquid;
An inkjet printing device comprising:
<13> A printing step of printing by ejecting the ink in the set of the ink and cleaning liquid according to any one of <1> to <11>;
a cleaning step of cleaning the ink remaining in the ink flow path or the recording head with the cleaning liquid in the set of the ink and the cleaning liquid;
An inkjet printing method comprising:
<14> A cleaning method for cleaning a nozzle surface of an ink ejection head using the cleaning liquid in the set of ink and cleaning liquid according to any one of <1> to <11>,
a step of applying the cleaning liquid to the wiping member;
a step of wiping the nozzle surface with a wiping member to which the cleaning liquid is applied;
A cleaning method comprising:
<15> A cleaning method for cleaning a nozzle surface of an ink ejection head using the cleaning liquid in the set of ink and cleaning liquid according to any one of <1> to <11>,
applying the cleaning liquid to the nozzle surface;
a step of wiping the nozzle surface to which the cleaning liquid is applied with a wiping member;
A cleaning method comprising:

A set of the ink and cleaning liquid according to any one of <1> to <11>, the inkjet printing device according to <12>, the inkjet printing method according to <13>, and <14> to <15>. > can solve the conventional problems and achieve the object of the present invention.

400 Image forming apparatus 401 Exterior of image forming apparatus 401c Cover of apparatus main body 404 Cartridge holder 410 Main tank 410k, 410c, 410m, 410y For black (K), cyan (C), magenta (M), and yellow (Y) main tank 411 ink storage unit 413 ink discharge port 414 storage container case 420 mechanism unit 434 ejection head 436 supply tube

JP 2017-114951 A JP 2017-119828 A

Claims (9)

an ink containing a coloring material and at least one of an acrylic resin and a urethane resin;
a cleaning liquid containing water and at least one organic solvent selected from diethylene glycol diethyl ether, diethylene glycol monobutyl ether and propylene glycol monopropyl ether ;
the glass transition temperature of the ink in a dry state is 40° C. or higher and 90° C. or lower;
A set of ink and cleaning liquid, wherein the swelling rate calculated based on the following formula 1 is 10% or more from the mass of the ink film obtained by drying the ink before and after being immersed in the cleaning liquid.
Swelling rate (%) = 100 × [(B - A) / A] ... Equation 1
However, in Equation 1, A represents the mass of the ink film before immersion, and B represents the mass of the ink film after immersion. 2. The ink and cleaning liquid set according to claim 1, wherein the swelling rate is 14% or more. 3. The ink and cleaning liquid set according to claim 1, wherein the resin in the ink has a glass transition temperature of 60[deg.] C. or higher. 4. The ink and cleaning liquid set according to any one of claims 1 to 3, wherein the content of the organic solvent is 10% by mass or more. the resin in the ink is an acrylic resin;
5. The ink and cleaning liquid set according to any one of claims 1 to 4, wherein the content of the acrylic resin in the ink is 3% by mass or more. a set of the ink and cleaning liquid according to any one of claims 1 to 5;
a recording head for printing by ejecting the ink in the ink and cleaning liquid set;
cleaning means for cleaning ink remaining in the ink channel or the recording head with the cleaning liquid in the set of the ink and the cleaning liquid;
An inkjet printing device comprising: a printing step of printing by ejecting the ink in the ink and cleaning liquid set according to any one of claims 1 to 5;
a cleaning step of cleaning the ink remaining in the ink flow path or the recording head with the cleaning liquid in the set of the ink and the cleaning liquid;
An inkjet printing method comprising: A cleaning method for cleaning a nozzle surface of an ink discharge head using the cleaning liquid in the ink and cleaning liquid set according to any one of claims 1 to 5, comprising:
a step of applying the cleaning liquid to the wiping member;
a step of wiping the nozzle surface with a wiping member to which the cleaning liquid is applied;
A cleaning method comprising: A cleaning method for cleaning a nozzle surface of an ink discharge head using the cleaning liquid in the ink and cleaning liquid set according to any one of claims 1 to 5, comprising:
applying the cleaning liquid to the nozzle surface;
a step of wiping the nozzle surface to which the cleaning liquid is applied with a wiping member;
A cleaning method comprising:

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