JP2023090029A - Cleaning fluid, set of cleaning fluid and ink, and inkjet system - Google Patents

Abstract

To provide a cleaning fluid having corrosion prevention ability for an ink discharge head and peripheral members and ink-removing ability.SOLUTION: A cleaning fluid comprises water, and an organic solvent containing a compound having two or more carbon atoms and two or three OH groups. The cleaning fluid has a pH of 7 or more and 10 or less, a phosphate ion concentration of 100 ppm or more and 5,000 ppm or less, a percentage of the organic solvent of 5 mass% or more and 20 mass% or less to the total amount of the cleaning fluid, and a percentage of the compound having two or three OH groups of 60 mass% or more and 100 mass% or less to the total amount of the organic solvent.SELECTED DRAWING: None

Description

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

Conventionally, dye inks have been the main stream of inkjet inks due to their good color development properties and high reliability.
BACKGROUND ART Screen printing, roller printing, rotary screen printing, gravure printing, or transfer printing methods using these printing techniques are known as methods for drawing a pattern on fabric with dyes in a robust and fine manner.
In recent years, the image of the pattern to be printed is read by a scanner, and the signal of the image processed by a computer is used to directly print (textile) on textile materials such as fabric (electrophotography or inkjet method). 2. Description of the Related Art A method of printing an image or the like on paper and transferring the image or the like to a fibrous material such as cloth has been put to practical use.

A wide variety of coloring materials and solvents are used for inks used for printing on textile materials such as the fabrics described above. In particular, since the chemical structure of the dye compound contains a reactive group, there is a concern that the deterioration of the ink itself may corrode the head, the members that come into contact with the ink, and the peripheral members.

Patent Document 1 proposes an aqueous ink for inkjet recording containing a colorant, water, and a water-soluble organic solvent, and that corrosion can be prevented by setting the phosphate ion concentration in the aqueous ink to 35 ppm or less. there is
Patent Document 2 discloses a method for protecting a metal surface that comes into contact with ink, comprising a phosphate with a concentration in the range of 0.01% by mass to 1.0% by mass and 0.001% by mass to 1.0% by mass. It has been proposed that corrosion of metal surfaces can be reduced by using an ink containing a concentration of citrate in the range of .

However, when inkjet ink remains in the inkjet head for a long period of time, the dyes and pigments of the ink may deteriorate. Especially when the pH of the ink is low or the electrical conductivity of the ink is high, the head and other parts in contact with the liquid may deteriorate. There is a problem that it easily invites corrosion. When the pH of the ink is low and the conductivity is high, the alteration reaction is accelerated, and corrosion is likely to occur. Corrosion may cause a change in the shape of the nozzle hole, a decrease in ejection stability, clogging of the ink, and an abnormality in the flight direction of the ink during ejection. In addition, if the corrosion progresses further, an ink leak occurs in which the ink leaks from members such as the head and the liquid feeding system that are in contact with the ink.

SUMMARY OF THE INVENTION An object of the present invention is to provide a cleaning liquid that is excellent in ink removability, prevents corrosion of an ink ejection head and peripheral members, and can maintain stable ejection characteristics over a long period of time.

The present invention, which solves the above problems, relates to a cleaning liquid having a configuration as described below.
A cleaning solution containing water and an organic solvent containing a compound having 2 or more carbon atoms and 2 or 3 OH groups,
pH is 7 or more and 10 or less,
The concentration of phosphate ions is 100 ppm or more and 5000 ppm or less,
The ratio of the organic solvent in the total amount of the cleaning liquid is 5% by mass or more and 20% by mass or less,
The cleaning liquid, wherein the ratio of the compound having two or three OH groups in the total amount of the organic solvent is 60% by mass or more and 100% by mass or less.

The cleaning liquid of the present invention has excellent ink removability, prevents corrosion of the ink ejection head and peripheral members, and can maintain stable ejection characteristics for a long period of time.

1 is an overall schematic diagram according to one embodiment of the present invention; FIG. 4 is a schematic diagram showing an example of a main tank in one embodiment of the present invention; FIG.

(washing liquid)
The cleaning liquid of the present invention is a cleaning liquid used for cleaning ink, and contains at least water and an organic solvent.
The organic solvent contains a compound having 2 or more carbon atoms and 2 or 3 OH groups.
Further, the cleaning liquid of the present invention has a pH of 7 or more and 10 or less, and a phosphate ion concentration of 100 ppm or more and 5000 ppm or less.
Further, the ratio of the organic solvent in the total amount of the cleaning liquid is 5% by mass or more and 20% by mass or less, and the ratio of the compound having 2 or 3 OH groups in the total amount of the organic solvent is 60% by mass. % or more and 100 mass % or less.

The cleaning liquid of the present invention preferably contains a surfactant and, if necessary, other components.

-Organic solvent-
Compounds having 2 or more carbon atoms and 2 or 3 OH groups, which are used as components of the organic solvent of the cleaning liquid, include propylene glycol, glycerin, 1,2-ethanediol, and dipropylene. It is at least one selected from the group consisting of glycols.
Further, other organic solvents preferably include compounds having an amide group-containing ring structure, and such compounds are preferably 2-pyrrolidone and/or ε-caprolactam.
The proportion of the organic solvent in the total amount of the cleaning liquid is 5% by mass or more and 20% by mass or less.
Moreover, the ratio of the compound having two or three OH groups in the total amount of the organic solvent is 60% by mass or more and 100% by mass or less.
As the organic solvent, it is possible to use the same organic solvents as the components of the ink which will be described later.

-water-
The water used for the cleaning liquid is not particularly limited and can be appropriately selected depending on the purpose. mentioned. The content in the cleaning solution is preferably 10% by mass or more and 98% by mass or less, more preferably 80% by mass or more and 95% by mass or less.

-resin-
The washing liquid may or may not contain a resin, but it is preferable that the washing liquid does not contain a resin.
When the cleaning liquid contains a resin, it is preferably the same kind and content as the resin contained in the ink described later.

-Additive-
The cleaning liquid of the present invention may contain a surfactant, an antiseptic/antifungal agent, an antirust agent, a pH adjuster, and the like, if necessary.

(Surfactant)
The surfactant is not particularly limited and can be appropriately selected depending on the intended purpose. Examples include surfactants.
These may be used individually by 1 type, or may use 2 or more types together.

（但し、一般式（Ｓ－１）式中、ｍ及びｎは、それぞれ独立に整数を表わし、Ｘは側鎖を表す。）
例えば、前記側鎖変性ポリジメチルシロキサンは、一般式（Ｓ－１）式で表わされるジメチルポリシロキサンのＳｉ部側鎖Ｘに、一般式（Ｓ－２）式で表わされるポリアルキレンオキシド構造を導入することで、ポリエーテル変性シリコーン系界面活性剤とすることができる。

（但し、一般式（Ｓ－２）式中ａ、及びｂは、それぞれ独立に整数を表わし、Ｒは、アルキレン基を表し、Ｒ’は、アルキル基を表す。） The silicone-based surfactant is not particularly limited and can be appropriately selected depending on the intended purpose, but one that does not decompose even at high pH is preferred. Examples thereof include side chain modified polydimethylsiloxane, both terminal modified polydimethylsiloxane, single terminal modified polydimethylsiloxane, and side chain both terminal modified polydimethylsiloxane.
The side chain-modified polydimethylsiloxane refers to, for example, introduction of a modifying group into the Si moiety side chain of the polydimethylsiloxane represented by the general formula (S-1).
The polydimethylsiloxane modified at both ends is, for example, introduced with modifying groups at both ends of the polydimethylsiloxane represented by general formula (S-1).
The one-end-modified polydimethylsiloxane refers to, for example, introduction of a modifying group to either one end of the polydimethylsiloxane represented by general formula (S-1).
The polydimethylsiloxane modified at both ends of the side chain is, for example, a polydimethylsiloxane represented by the general formula (S-1), in which modifying groups are introduced into the Si portion side chain and both ends.

(However, in the general formula (S-1), m and n each independently represent an integer, and X represents a side chain.)
For example, the side chain-modified polydimethylsiloxane is introduced with a polyalkylene oxide structure represented by the general formula (S-2) into the Si portion side chain X of the dimethylpolysiloxane represented by the general formula (S-1). By doing so, a polyether-modified silicone-based surfactant can be obtained.

(However, in the general formula (S-2), a and b each independently represent an integer, R represents an alkylene group, and R' represents an alkyl group.)

The modifying group is not particularly limited and can be appropriately selected depending on the purpose. Examples thereof include polyoxyethylene groups, polyoxyethylene polyoxypropylene groups, polyalkylene oxide structures, and the like.

As the silicone-based surfactant, an appropriately synthesized one may be used, or a commercially available product may be used.
Commercially available silicone surfactants are available from, for example, BYK Chemie Co., Ltd., Shin-Etsu Chemical Co., Ltd., Dow Corning Toray Silicone Co., Ltd., Nippon Emulsion Co., Ltd., Kyoeisha Chemical Co., Ltd., and the like.
As the polyether-modified silicone surfactant, commercially available products can be used, for example, KF-642, KF-643 (Shin-Etsu Chemical Co., Ltd.), DOWSIL FZ-2105, DOWSIL FZ-2154, DOWSIL FZ- 2161, DOWSIL FZ-2162, DOWSIL FZ-2164 (Dow Corning Toray Silicone Co., Ltd.) and the like.

（但し、一般式（Ｆ－１）において、ｍ及びｎは、それぞれ独立に整数を表す。）
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。
一般式（Ｆ－２）
Ｃ_ｎＦ_2ｎ+1－ＣＨ₂ＣＨ（ＯＨ）ＣＨ₂－Ｏ－（ＣＨ₂ＣＨ₂Ｏ）_ａ－Ｙ
（ただし、上記一般式（Ｆ－２）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－ＣｍＦ_２ｍ＋１でｍは４～６の整数、又はＣｐＨ_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。） The fluorine-based surfactant is not particularly limited and can be appropriately selected depending on the intended purpose. Examples include fluoroalkylethylene 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.
More preferably, the fluorosurfactant is a compound represented by general formula (F-1) or general formula (F-2).

(However, in general formula (F-1), m and n each independently represent an integer.)
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.
General formula (F-2)
_{CnF2n +1- CH2CH} (OH)CH2 _- O-( _CH2CH2O ) _{a -} Y
(However, in the above 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 -CmF _2m+1 and m is 4 to 6 integer, or CpH _2p+1 where p is an integer from 1 to 19, n is an integer from 1 to 6, and a is an integer from 4 to 14.)

Specific examples of the perfluoroalkylsulfonic acid compound include perfluoroalkylsulfonic acid and perfluoroalkylsulfonate.

Specific examples of the perfluoroalkylcarboxylic acid compounds include perfluoroalkylcarboxylic acids and perfluoroalkylcarboxylic acid salts.

Specific examples of the polyoxyalkylene ether polymer compound having a perfluoroalkyl ether group in a side chain include, for example, a sulfate ester salt of a polyoxyalkylene ether polymer having a perfluoroalkyl ether group in a side chain, and a perfluoroalkyl ether group. and salts of polyoxyalkylene ether polymers having in the side chains.

Counter _{ions of salts} in the fluorosurfactant include Li, Na, K, _NH4 , _NH3CH2CH2OH , _NH2 ( _CH2CH2OH ) ₂ , _and NH( _CH2CH2OH ). ₃ and the like.

The fluorine-based surfactant is not particularly limited and can be appropriately selected depending on the intended purpose, but a fluorine-substituted compound having 2 to 16 carbon atoms is preferable, and a fluorine-substituted compound having 4 to 16 carbon atoms is preferable. Certain compounds are more preferred.

A commercially available product may be used as the fluorosurfactant.
Examples of commercially available fluorosurfactants include Surflon S-111, Surflon S-112, Surflon S-113, Surflon S-121, Surflon S-131, Surflon S-132, Surflon S-141, Surflon S-145 (both from AGC Seimi Chemical Co., Ltd.), Fleurad FC-93, Fleurad FC-95, Fleurad FC-98, Fleurad FC-129, Flellard FC-135, Flellard FC-170C, Flellard FC-430, Flellard FC-431 (both manufactured by 3M Japan Co., Ltd.), Megafac F-470, Megafac F-1405, Megafac F-474 (both manufactured by DIC Corporation), Zonyl TBS, Zonyl ) FSP, Zonyl FSA, Zonyl FSN-100, Zonyl FSN, Zonyl FSO-100, Zonyl FSO, Zonyl FS-300, Zonyl UR , Capstone FS-30, Capstone FS-31, Capstone FS-3100, Capstone FS-34, Capstone 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, Polyfox PF-156A, Polyfox PF-151N, Polyfox PF-154, Polyfox PF- 159 (manufactured by Omnova), Unidyne DSN-403N (manufactured by Daikin Industries, Ltd.), and the like. Among these, Zonyl FS-300, Zonyl FS-3100, Capstone FS-34, (all of them are Chemours), FT-110, FT-250, FT-251, FT-400S, FT-150, FT-400SW (all manufactured by Neos Co., Ltd.), Polyfox PF-151N (manufactured by Omnova), Unidyne DSN -403N (manufactured by Daikin Industries, Ltd.) is preferred.

The amphoteric surfactant is not particularly limited and can be appropriately selected depending on the intended purpose. Examples thereof include laurylaminopropionate, lauryldimethylbetaine, stearyldimethylbetaine, lauryldihydroxyethylbetaine and the like.

The nonionic surfactant is not particularly limited and can be appropriately selected depending on the intended purpose. Examples include amides, polyoxyethylene propylene block polymers, sorbitan fatty acid esters, polyoxyethylene sorbitan fatty acid esters, and ethylene oxide adducts of acetylene alcohol.

The anionic surfactant is not particularly limited and can be appropriately selected depending on the intended purpose. Examples include sulfate salts.

The content of the surfactant in the ink is not particularly limited, but is preferably 0.001% by mass or more and 5% by mass or less from the viewpoint of excellent wettability and ejection stability and improved image quality. 0.05% by mass or more and 5% by mass or less is more preferable.

Said surfactants can be used as antifoaming agents.
The antifoaming agent is not particularly limited and can be appropriately selected depending on the intended purpose. Examples thereof include silicone antifoaming agents, polyether antifoaming agents, fatty acid ester antifoaming agents and the like. Among these, silicone-based antifoaming agents are preferred because of their excellent foam breaking effect.
These may be used individually by 1 type, and may use 2 or more types together.

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

(anti-rust)
The rust preventive is not particularly limited as long as it exhibits a rust preventive action, and examples thereof include heterocyclic aromatic compounds.
The heterocyclic aromatic compound bonds with metal ions to form an insoluble film, thereby exhibiting an anticorrosive effect on the metal parts in the nozzle.

The heterocyclic aromatic compound is not particularly limited and can be appropriately selected depending on the intended purpose. Examples thereof include benzotriazole compounds.

The benzotriazole compound is not particularly limited and can be appropriately selected depending on the intended purpose. -5-t-butylphenyl)benzotriazole, 2-(2-hydroxy-5-t-octylphenyl)benzotriazole and the like.

The content of the benzotriazole compound in the ink is not particularly limited, but is preferably 0.001% by mass or more and 1.0% by mass or less, more preferably 0.005% by mass or more and 0.5% by mass or less. .

(Phosphate compound)
The phosphoric acid-based compound contained in the cleaning liquid is not particularly limited and can be appropriately selected depending on the intended purpose. Examples thereof include sodium hydrogen phosphate, lithium phosphate, sodium phosphate, potassium phosphate and ammonium phosphate. .
The concentration of phosphate ions contained in the cleaning liquid is preferably 100 ppm or more and 5000 ppm or less.

(pH adjuster)
The pH adjuster is not particularly limited as long as it can adjust the pH to 7 or more and 10 or less, and examples thereof include amines such as diethanolamine and triethanolamine. Moreover, a pH buffer may be contained in order to stabilize the pH. The pH buffer is not particularly limited, and examples thereof include phosphoric acid compounds and N-cyclohexyl-2-aminoethanesulfonic acid.

The physical properties of the cleaning liquid of the present invention 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 surface tension of the cleaning liquid of the present invention at 25° C. is not particularly limited, but is preferably 35 mN/m or less, more preferably 32 mN, from the viewpoint that the ink is suitably leveled on the recording medium and the drying time of the ink is shortened. /m or less is more preferable.

(ink)
The ink in the ink of the present invention contains water, an organic solvent, and a coloring material.
A dye or a pigment can be used as the coloring material.

-dye-
Dyes contained in the ink are not particularly limited, and reactive dyes, acid dyes, direct dyes, and basic dyes can be used. may When the coloring material in the present invention is a dye, the effect is high in many cases, and the effect is particularly high when the coloring material is a reactive dye. Suitable dyes are not particularly limited as long as they are reactive dyes, and can be appropriately selected according to the purpose. Since it can be improved, corrosion is particularly likely to occur, so the cleaning liquid, ink set, and inkjet system of the present invention are highly effective. Specific examples of reactive dyes include C.I. I. Reactive Black 1, C.I. I. Reactive Black 3, C.I. I. Reactive Black 5, C.I. I. Reactive Black 8, C.I. I. Reactive Black 10, C.I. I. Reactive Black 12, C.I. I. Reactive Black 13, C.I. I. Reactive Black 39, C.I. I. Reactive Blue 2, C.I. I. Reactive Blue 3, C.I. I. Reactive Blue 5, C.I. I. Reactive Blue 7, C.I. I. Reactive Blue 13, C.I. I. Reactive Blue 14, C.I. I. Reactive Blue 15, C.I. I. Reactive Blue 25, C.I. I. Reactive Blue 26, C.I. I. Reactive Blue 39, C.I. I. Reactive Blue 40, C.I. I. Reactive Blue 49, C.I. I. Reactive Red 3, C.I. I. Reactive Red 4, C.I. I. Reactive Red 7, C.I. I. Reactive Red 15, C.I. I. Reactive Red 16, C.I. I. Reactive Red 24, C.I. I. Reactive Red 29, C.I. I. Reactive Red 31, C.I. I. Reactive Red 32, C.I. I. Reactive Red 33, C.I. I. Reactive Red 43, C.I. I. Reactive Red 45, C.I. I. Reactive Red 46, C.I. I. Reactive Red 58, C.I. I. Reactive Red 59, C.I. I. Reactive Red 256, C.I. I. Reactive Red 245, C.I. I. Reactive Yellow 3, C.I. I. Reactive Yellow 6, C.I. I. Reactive Yellow 12, C.I. I. Reactive Yellow 18, C.I. I. Reactive Yellow 95, C.I. I. Reactive Yellow 99, C.I. I. Reactive Orange 2, C.I. I. Reactive Orange 5, C.I. I. Reactive Orange 9, C.I. I. Reactive Orange 12, C.I. I. Reactive Orange 13, C.I. I. Reactive Orange 39, C.I. I. Reactive Green 5, C.I. I. Reactive Green 8, C.I. I. reactive violet 1, C.I. I. and Reactive Violet 2.
These may be used individually by 1 type, and may use 2 or more types together.

Examples of the acid dye include C.I. I. Acid Yellow 17, C.I. I. Acid Yellow 23, C.I. I. Acid Yellow 42, C.I. I. Acid Yellow 44, C.I. I. Acid Yellow 79, C.I. I. Acid Yellow 142, C.I. I. Acid Red 1, C.I. I. Acid Red 8, C.I. I. Acid Red 13, C.I. I. Acid Red 14, C.I. I. Acid Red 18, C.I. I. Acid Red 26, C.I. I. Acid Red 27, C.I. I. Acid Red 35, C.I. I. Acid Red 37, C.I. I. Acid Red 42, C.I. I. Acid Red 52, C.I. I. Acid Red 82, C.I. I. Acid Red 87, C.I. I. Acid Red 89, C.I. I. Acid Red 92, C.I. I. Acid Red 97, C.I. I. Acid Red 106, C.I. I. Acid Red 111, C.I. I. Acid Red 114, C.I. I. Acid Red 115, C.I. I. Acid Red 134, C.I. I. Acid Red 186, C.I. I. Acid Red 249, C.I. I. Acid Red 254, C.I. I. Acid Red 289, C.I. I. Acid Blue 9, C.I. I. Acid Blue 29, C.I. I. Acid Blue 45, C.I. I. Acid Blue 92, C.I. I. Acid Blue 249, C.I. I. Acid Black 1, C.I. I. Acid Black 2, C.I. I. Acid Black 7, C.I. I. Acid Black 24, C.I. I. Acid Black 26, C.I. I. Acid Black 94 and the like.
Examples of the food dye include C.I. I. Food Yellow 3, C.I. I. Food Red 14, C.I. I. Hood Black 1, C.I. I. Hood Black 2 and the like.

Examples of the direct dye include C.I. I. Direct Yellow 1, C.I. I. Direct Yellow 12, C.I. I. Direct Yellow 24, C.I. I. Direct Yellow 26, C.I. I. Direct Yellow 33, C.I. I. Direct Yellow 44, C.I. I. Direct Yellow 50, C.I. I. Direct Yellow 86, C.I. I. Direct Yellow 120, C.I. I. Direct Yellow 132, C.I. I. Direct Yellow 142, C.I. I. Direct Yellow 144, C.I. I. Direct Red 1, C.I. I. Direct Red 4, C.I. I. Direct Red 9, C.I. I. Direct Red 13, C.I. I. Direct Red 17, C.I. I. Direct Red 20, C.I. I. Direct Red 28, C.I. I. Direct Red 31, C.I. I. Direct Red 39, C.I. I. Direct Red 80, C.I. I. Direct Red 81, C.I. I. Direct Red 83, C.I. I. Direct Red 89, C.I. I. Direct Red 225, C.I. I. Direct Red 227, C.I. I. Direct Orange 26, C.I. I. Direct Orange 29, C.I. I. Direct Orange 62, C.I. I. Direct Orange 102, C.I. I. Direct Blue 1, C.I. I. Direct Blue 2, C.I. I. Direct Blue 6, C.I. I. Direct Blue 15, C.I. I. Direct Blue 22, C.I. I. Direct Blue 25, C.I. I. Direct Blue 71, C.I. I. Direct Blue 76, C.I. I. Direct Blue 79, C.I. I. Direct Blue 86, C.I. I. Direct Blue 87, C.I. I. Direct Blue 90, C.I. I. Direct Blue 98, C.I. I. Direct Blue 163, C.I. I. Direct Blue 165, C.I. I. Direct Blue 199, C.I. I. Direct Blue 202, C.I. I. Direct Black 19, C.I. I. Direct Black 22, C.I. I. Direct Black 32, C.I. I. Direct Black 38, C.I. I. Direct Black 51, C.I. I. Direct Black 56, C.I. I. Direct Black 71, C.I. I. Direct Black 74, C.I. I. Direct Black 75, C.I. I. Direct Black 77, C.I. I. Direct Black 154, C.I. I. Direct Black 168, C.I. I. Direct Black 171 and the like can be mentioned.

Examples of the basic dye include C.I. I. Basic Yellow 1, C.I. I. Basic Yellow 2, C.I. I. Basic Yellow 11, C.I. I. Basic Yellow 13, C.I. I. Basic Yellow 14, C.I. I. Basic Yellow 15, C.I. I. Basic Yellow 19, C.I. I. Basic Yellow 21, C.I. I. Basic Yellow 23, C.I. I. Basic Yellow 24, C.I. I. Basic Yellow 25, C.I. I. Basic Yellow 28, C.I. I. Basic Yellow 29, C.I. I. Basic Yellow 32, C.I. I. Basic Yellow 36, C.I. I. Basic Yellow 40, C.I. I. Basic Yellow 41, C.I. I. Basic Yellow 45, C.I. I. Basic Yellow 49, C.I. I. Basic Yellow 51, C.I. I. Basic Yellow 53, C.I. I. Basic Yellow 63, C.I. I. Basic Yellow 64, C.I. I. Basic Yellow 65, C.I. I. Basic Yellow 67, C.I. I. Basic Yellow 70, C.I. I. Basic Yellow 73, C.I. I. Basic Yellow 77, C.I. I. Basic Yellow 87, C.I. I. Basic Yellow 91, C.I. I. Basic Red 2, C.I. I. Basic Red 12, C.I. I. Basic Red 13, C.I. I. Basic Red 14, C.I. I. Basic Red 15, C.I. I. Basic Red 18, C.I. I. Basic Red 22, C.I. I. Basic Red 23, C.I. I. Basic Red 24, C.I. I. Basic Red 27, C.I. I. Basic Red 29, C.I. I. Basic Red 35, C.I. I. Basic Red 36, C.I. I. Basic Red 38, C.I. I. Basic Red 39, C.I. I. Basic Red 46, C.I. I. Basic Red 49, C.I. I. Basic Red 51, C.I. I. Basic Red 52, C.I. I. Basic Red 54, C.I. I. Basic Red 59, C.I. I. Basic Red 68, C.I. I. Basic Red 69, C.I. I. Basic Red 70, C.I. I. Basic Red 73, C.I. I. Basic Red 78, C.I. I. Basic Red 82, C.I. I. Basic Red 102, C.I. I. Basic Red 104, C.I. I. Basic Red 109, C.I. I. Basic Red 112, C.I. I. Basic Blue 1, C.I. I. Basic Blue 3, C.I. I. Basic Blue 5, C.I. I. Basic Blue 7, C.I. I. Basic Blue 9, C.I. I. Basic Blue 21, C.I. I. Basic Blue 22, C.I. I. Basic Blue 26, C.I. I. Basic Blue 35, C.I. I. Basic Blue 41, C.I. I. Basic Blue 45, C.I. I. Basic Blue 47, C.I. I. Basic Blue 54, C.I. I. Basic Blue 62, C.I. I. Basic Blue 65, C.I. I. Basic Blue 66, C.I. I. Basic Blue 67, C.I. I. Basic Blue 69, C.I. I. Basic Blue 75, C.I. I. Basic Blue 77, C.I. I. Basic Blue 78, C.I. I. Basic Blue 89, C.I. I. Basic Blue 92, C.I. I. Basic Blue 93, C.I. I. Basic Blue 105, C.I. I. Basic Blue 117, C.I. I. Basic Blue 120, C.I. I. Basic Blue 122, C.I. I. Basic Blue 124, C.I. I. Basic Blue 129, C.I. I. Basic Blue 137, C.I. I. Basic Blue 141, C.I. I. Basic Blue 147, C.I. I. Basic Blue 155, C.I. I. Basic Black 2, C.I. I. Basic Black 8 and the like.

Other reactive dyes include, for example, C.I. I. Reactive Black 4, C.I. I. Reactive Black 7, C.I. I. Reactive Black 11, C.I. I. Reactive Black 17, C.I. I. Reactive Yellow 1, C.I. I. Reactive Yellow 5, C.I. I. Reactive Yellow 11, C.I. I. Reactive Yellow 13, C.I. I. Reactive Yellow 14, C.I. I. Reactive Yellow 20, C.I. I. Reactive Yellow 21, C.I. I. Reactive Yellow 22, C.I. I. Reactive Yellow 25, C.I. I. Reactive Yellow 40, C.I. I. Reactive Yellow 47, C.I. I. Reactive Yellow 51, C.I. I. Reactive Yellow 55, C.I. I. Reactive Yellow 65, C.I. I. Reactive Yellow 67, C.I. I. Reactive Red 1, C.I. I. Reactive Red 14, C.I. I. Reactive Red 17, C.I. I. Reactive Red 25, C.I. I. Reactive Red 26, C.I. I. Reactive Red 37, C.I. I. Reactive Red 44, C.I. I. Reactive Red 55, C.I. I. Reactive Red 60, C.I. I. Reactive Red 66, C.I. I. Reactive Red 74, C.I. I. Reactive Red 79, C.I. I. Reactive Red 96, C.I. I. Reactive Red 97, C.I. I. Reactive Blue 23, C.I. I. Reactive Blue 32, C.I. I. Reactive Blue 35, C.I. I. Reactive Blue 38, C.I. I. Reactive Blue 41, C.I. I. Reactive Blue 63, C.I. I. Reactive Blue 80, C.I. I. Examples include Reactive Blue 95.

The content of the dye in the ink is not particularly limited, and is preferably 0.1% by mass or more and 15% by mass or less, and 1% by mass, from the viewpoints of improvement in image density, good fixability and ejection stability. It is more preferable to be 10% by mass or less.

-Pigments-
A pigment can also be used as the coloring material contained in the ink. 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.

The content of the pigment in the ink is not particularly limited, and is preferably 0.1% by mass or more and 15% by mass or less, and 1% by mass, from the viewpoints of improvement in image density, good fixability and ejection stability. It is more preferable to be 10% by mass or less.

-water-
The water is not particularly limited and can be appropriately selected depending on the intended purpose.
The content of the 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.

-Organic solvent-
The organic solvent, which is a constituent material of the ink, is not particularly limited as long as it is a water-soluble organic solvent, and can be appropriately selected according to the purpose. and other ethers, nitrogen-containing heterocyclic compounds, amides, amines, sulfur-containing compounds, and the like.
These may be used individually by 1 type, or may use 2 or more types together.

Specific examples of the water-soluble organic solvent include ethylene glycol, diethylene glycol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 2,3- butanediol, 3-methyl-1,3-butanediol, triethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, polypropylene glycol, 1,2-pentanediol, 1,3-pentanediol, 1,4-pentane Diol, 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 - Polyhydric alcohols such as 1,3-pentanediol and petriol, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, tetraethylene glycol monomethyl ether, propylene glycol mono Polyhydric alcohol alkyl ethers such as ethyl ether, polyhydric alcohol aryl ethers such as ethylene glycol monophenyl ether and ethylene glycol monobenzyl ether, 2-pyrrolidone, N-methyl-2-pyrrolidone, N-hydroxyethyl-2- nitrogen-containing heterocyclic compounds such as pyrrolidone, 1,3-dimethyl-2-imidazolidinone, ε-caprolactam, γ-butyrolactone, formamide, N-methylformamide, N,N-dimethylformamide, 3-methoxy-N,N - Amides such as dimethylpropionamide and 3-butoxy-N,N-dimethylpropionamide, amines such as monoethanolamine, diethanolamine, and triethylamine, sulfur-containing compounds such as dimethylsulfoxide, sulfolane, and thiodiethanol, propylene carbonate, and carbonic acid ethylene and the like.

As the water-soluble organic solvent, a polyol compound having 8 or more carbon atoms and a glycol ether compound are preferably used when paper is used as a recording medium, and can improve the permeability of ink to paper.
Specific examples of the polyol compound having 8 or more carbon atoms include 2-ethyl-1,3-hexanediol and 2,2,4-trimethyl-1,3-pentanediol.
Specific examples of the glycol ether compounds include polyhydric alcohols 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. polyhydric alcohol aryl ethers such as alkyl ethers, ethylene glycol monophenyl ether, ethylene glycol monobenzyl ether, and the like;

The boiling point of the organic solvent is not particularly limited, and is preferably 250° C. or less from the viewpoint of wetting effect and good drying property.

The content of the organic solvent in the ink is not particularly limited, but is preferably 10% by mass or more and 60% by mass or less, more preferably 20% by mass or more and 60% by mass or less, from the viewpoint of ink drying property and ejection reliability. preferable.

-resin-
The type of resin contained in the ink is not particularly limited and can be appropriately selected according to the purpose. resins, styrene-butadiene-based resins, vinyl chloride-based resins, acrylic-styrene-based resins, acrylic-silicone-based resins, and the like. Resin particles made of these resins may also be used.
These may be used individually by 1 type, or may use 2 or more types together.
The resin particles can be mixed with a material such as a coloring material or an organic solvent in a resin emulsion state in which water is used as a dispersion medium to obtain an ink.

The volume average particle diameter of the resin particles is not particularly limited, 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 10 nm or more and 100 nm or less, from the viewpoint of obtaining good fixability and high image hardness. The following are particularly preferred.
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 in the ink is not particularly limited, but is preferably 1% by mass or more and 30% by mass or less, and 5% by mass or more and 20% by mass or less from the viewpoint of fixability and storage stability of the ink. more preferred.

-Additive-
Surfactants, antiseptic antifungal agents, antirust agents, pH adjusters and the like may be added to the inks in the ink set of the present invention, if necessary.

(Surfactant)
As the surfactant, the same surfactants as those described as the components of the cleaning liquid can be used.

(antiseptic and antifungal agent)
As the antiseptic/antifungal agent, the same antiseptic/antifungal agent as described as the component of the cleaning liquid can be used.

(pH adjuster)
As the pH adjuster, the same one as the pH adjuster described as the component of the cleaning liquid can be used.

(alkaline earth metal ion)
The ink in the ink set of the present invention can contain alkaline earth metal ions, if desired.
The alkaline earth metal ion is not particularly limited and can be appropriately selected depending on the intended purpose. Examples thereof include calcium ion and magnesium ion.

The content of the alkaline earth metal ions in the ink is preferably 50 ppm or less, more preferably 30 ppm or less, because it may dissolve the silicone resin in the ink-repellent layer.

The physical properties of the ink of the present invention are not particularly limited and can be appropriately selected depending on the intended purpose.

The viscosity of the ink at 25° C. in the ink set of the present invention is not particularly limited, but is 0.5 mPa·s or more and 30 mPa from the viewpoint of improving print density and character quality and obtaining good ejection properties. ·s or less, more preferably 2 mPa·s or more and 25 mPa·s or less, still more preferably 5 mPa·s or more and 25 mPa·s or less.
The viscosity can be measured using, for example, a rotational viscometer (RE-80L manufactured by Toki Sangyo Co., Ltd.). 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 at 25° C. in the ink set of the present invention is not particularly limited, but is preferably 35 mN/m or less from the viewpoint that the ink is suitably leveled on the recording medium and the drying time of the ink is shortened. It is preferably 32 mN/m or less, more preferably 32 mN/m or less.

The pH of the ink at 25° C. in the ink set of the present invention is not particularly limited, but is preferably 6 to 12, more preferably 7 to 11, from the viewpoint of preventing corrosion of metal members in contact with the liquid.

[Inkjet system]
The ink jet system of the present invention includes an ink container that contains ink, an ink discharge head that discharges the ink, an ink supply path that connects the ink discharge head and the ink container, and ink in the ink discharge head. a cleaning liquid container containing cleaning liquid for replacing ink in the ink supply path; and cleaning liquid supply means for supplying the cleaning liquid in the cleaning liquid storage container to the ink supply path and the ink discharge head. In an inkjet system, the ink and the cleaning liquid are the ink and the cleaning liquid in the set of the cleaning liquid and the ink of the present invention. Moreover, it has other means as needed.

The inkjet system of the present invention supplies the cleaning liquid of the present invention to the ink supply path and the ink ejection head when the ink is not continuously supplied to the ejection head within a preset time, thereby supplying the ink. It is preferable to provide means for replacing the ink in the channels and ink ejection heads with the cleaning liquid.

<Recording medium>
A recording medium in the present invention is an object to be recorded using the inkjet system of the present invention.
The recording medium means a medium to which ink and various treatment liquids can adhere even temporarily.
Examples of the recording medium include, but are not limited to, 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, etc. can be used as appropriate. Ceramics, glass, metal, etc. can also be used by adjusting the structure of the path for conveying the recording medium.

<Records>
The recorded matter in the present invention can be made into a recorded matter by recording with a recording apparatus and a recording method equipped with the inkjet system of the present invention.
The recorded matter has an image or the like formed on the recording medium using the inkjet system of the present invention.

<Recording device, recording method>
The recording apparatus and recording method of the present invention refer to an apparatus equipped with the ink jet system of the present invention capable of ejecting ink, various treatment liquids, etc. onto a recording medium, and a method of performing recording using the apparatus. .
The ink set of the present invention can be suitably used for various recording apparatuses using an inkjet recording method, such as printers, facsimile machines, copiers, printer/fax/copier complex machines, stereolithography machines, and the like.

The recording apparatus may include not only a head portion for ejecting ink, but also means for feeding, conveying, and discharging the recording medium, and other devices called pre-processing devices and post-processing devices. can.

The recording apparatus and the recording method may have heating means for use in the heating process and drying means for use in the drying process.
The heating means and the 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, and for example, hot air heaters and infrared heaters can be used.
The heating means and the drying means can be performed before, during, or after printing.

The recording apparatus and the recording method are not limited to those in which significant images such as characters and graphics are visualized with ink. For example, it includes those that form patterns such as geometric patterns, and those that form three-dimensional images.

Unless otherwise specified, the recording 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.
Further, the recording device is not limited to desktop type, but it is possible to use a wide recording device capable of printing on A0 size recording medium, and continuous paper wound into a roll as a recording medium. A continuous feed printer is also included.

The recording apparatus can include not only a portion that ejects ink, but also devices called pre-processing devices and post-processing devices.
As one aspect of the pre-treatment device and the post-treatment device, cleaning liquid, pre-treatment liquid, There is a mode in which a liquid containing portion having a treatment liquid and a liquid ejection head are added, and a pretreatment liquid and a 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.

When the printer equipped with the inkjet system of the present invention does not operate continuously for a preset time, the ink is replaced with the cleaning liquid of the present invention to avoid contact between the ink and the head and other units and members for a long period of time. Corrosion risk can be reduced. Materials that corrode include metals, and places where metals are used include the housing of the head and the joints of the liquid transfer system, and SUS is the main metal material. Further, the cleaning liquid of the present invention has a low risk of corrosion even when in contact with the head or the like for a long period of time. It is preferable to replace the ink with the cleaning liquid when the printer does not operate continuously for one day to three weeks, and it is more preferable to replace the ink with the cleaning liquid when the printer does not operate continuously for two days to one week.

It is preferable to perform wiping in parallel with the replacement of the ink with the cleaning liquid, because clogging of the nozzle holes of the head can be reduced.

After replacing the ink with the cleaning liquid, it is more preferable to repeat wiping and blank discharge of the cleaning liquid a plurality of times because clogging of the nozzle holes of the head is less likely to occur.

A known three-dimensional modeling apparatus for forming the three-dimensional object can be used, and is not particularly limited. can do. 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. The molded product is, for example, a sheet-shaped or film-shaped recorded matter or structure that has been subjected to molding such as heat stretching or punching.・Suitably used for applications where molding is performed after the surface is decorated, such as electronic equipment, meters for cameras, and operation panels.

An example of the recording apparatus will be described below with reference to FIGS. 1 and 2. FIG. FIG. 1 is a perspective explanatory view of a recording apparatus. FIG. 2 is a perspective explanatory view of the main tank.
An image forming apparatus 400 as an example of a recording 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 packed with, for example, an aluminum laminated film. It is made up of members. 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.

The use of the ink of the present invention is not particularly limited and can be appropriately selected according to the intended 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 image (three-dimensional object).

Image formation, recording, printing, printing, etc. in the terms of the present invention are all synonymous.

Examples and comparative examples of the present invention are shown below, but the present invention is not limited to these.

<Preparation of washing solution>
Table 1 shows the composition of the cleaning solution. Numerical values in the table indicate % by mass.
Each component was placed in a container so as to have the composition shown in Table 1, stirred for 2 hours, and then filtered through a membrane filter having a pore size of 0.45 μm to obtain cleaning liquids 1 to 12.
・Water (ion-exchanged water)
・Propylene glycol (manufactured by FUJIFILM Wako Pure Chemical Industries, Ltd.)
・Glycerin (manufactured by FUJIFILM Wako Pure Chemical Industries, Ltd.)
・ 1,2-ethanediol (manufactured by Sankyo Co., Ltd.)
・Dipropylene glycol (manufactured by Tokyo Chemical Industry Co., Ltd.)
・ 1,3-propanediol (manufactured by Tokyo Chemical Industry Co., Ltd.)
・2-Pyrrolidone (manufactured by Mitsubishi Chemical Corporation)
・ε-caprolactam (manufactured by Ube Industries, Ltd.)
・ 3-ethyl-3-hydroxymethyloxetane (manufactured by Tokyo Chemical Industry Co., Ltd.)
・ 1,2,3-benzotriazole (manufactured by Johoku Chemical Industry Co., Ltd.)
・Proxel LV (manufactured by Avecia)
・ LS-106 (manufactured by Kao Corporation)
・Sodium hydrogen phosphate (manufactured by FUJIFILM Wako Pure Chemical Industries, Ltd.)
・ 2-amino-2-ethyl-1,3-propanediol (manufactured by FUJIFILM Wako Pure Chemical Industries, Ltd.)
・N-Cyclohexyl-2-aminoethanesulfonic acid (manufactured by Dojindo Laboratories)
・Diluted nitric acid (manufactured by Kanto Chemical Co., Ltd.)

The pH and electrical conductivity of the resulting cleaning solution were measured.
The pH was measured at a constant temperature of 25° C. using a multi-water quality meter (manufactured by Toa TDK Co., Ltd.).
The electrical conductivity was measured using a multi-water quality meter (manufactured by Toa TDK Co., Ltd.).
Each measured value is shown in Table 1.

<Ink preparation>
Table 2 shows the ink formulation.
The following materials were placed in a container so as to have the composition shown in Table 2, stirred for 2 hours, and filtered through a membrane filter with a pore size of 0.45 μm to obtain inks 1 to 12.
・Water (ion-exchanged water)
・Propylene glycol (manufactured by FUJIFILM Wako Pure Chemical Industries, Ltd.)
・Glycerin (manufactured by FUJIFILM Wako Pure Chemical Industries, Ltd.)
・Dipropylene glycol (manufactured by Tokyo Chemical Industry Co., Ltd.)
・2-Pyrrolidone (manufactured by Mitsubishi Chemical Corporation)
・ε-caprolactam (manufactured by Ube Industries, Ltd.)
・ 1,2,3-benzotriazole (manufactured by Johoku Chemical Industry Co., Ltd.)
・Proxel LV (manufactured by Avecia)
・Bk39 (C.I. Reactive Black 39)
・Red24 (C.I. Reactive Red 24)
・Red245 (C.I. Reactive Red 245)
・Or13 (C.I. Reactive Orange 13)
・Bl49 (C.I. Reactive Blue 49)
・Y95 (C.I. Reactive Yellow 95)
・Bk5 (C.I. Reactive Black 5)
・Direct Bl199 (C.I. Direct Blue 199)
・Acid Bk 172 (C.I. Acid Black 172)
・Acid Red 249 (C.I. Acid Red 249)

Inks 13, 14 and 15 below were used as pigment inks.
The inks 13 and 14 are inks containing resin.
Ink 13: LX100/LX101 latex ink cartridge white ink (manufactured by Mimaki Engineering Co., Ltd., product number: LX100-W-22), which is a resin-containing ink
Ink 14: HP 831B 775-ml magenta Latex ink cartridge (manufactured by HP, product number: CZ690A), which is a resin-containing ink
Ink 15: Garment ink CGX-4W50 white ink (manufactured by Brother Industries, Ltd.)

Using the washing liquids 1 to 12 and inks 1 to 15, an ink washing test with the washing liquid was carried out according to the following test method in the combinations shown in Table 3 below.
20 ml of ink is filled into a syringe and filled into a tube having an inner diameter of 1 mm and a length of 50 cm. Then fill 50 ml of the washing solution into the syringe. The ink in the tube filled with the ink is extruded with 50 ml of cleaning liquid, and it is observed whether the color of the ink can be confirmed.
The evaluation results were evaluated according to the following evaluation criteria.
Table 3 shows the evaluation results.
(Evaluation criteria)
O: It was transparent.
Δ: Ink color was confirmed.

(Examples 1 to 6, Comparative Examples 1 to 6)
For cleaning solutions 1 to 12, 30 ml of cleaning solution and cylindrical SUS303 with a diameter of 10 mm and a length of 40 mm were put into a polypropylene container, and the container was stored at 50° C. for 7 days. The condition was observed, and the Fe elution amount of each cleaning solution was measured.
The eluted Fe amount was measured using ICPE-9000 (manufactured by Shimadzu Corporation).
Table 4 shows the evaluation results.

In addition, the following ejection test was performed using an inkjet head MH5241F manufactured by Ricoh.
- The inkjet head was filled with the cleaning liquid and stored as it was at 50°C for 7 days.
- The cleaning liquid was taken out from the inkjet head, and the inkjet head was cleaned using the same cleaning liquid as the filled cleaning liquid and stored at room temperature.
Ink 1 was ejected from the inkjet head, and the ejection status of the ink was evaluated according to the following evaluation criteria using whether or not the ejected droplet landed at the correct position (landing accuracy) as an evaluation index.
Table 4 shows the evaluation results.
In addition, in an ejection test using the ink and the ink head stored at room temperature, it was confirmed that there was no problem in the ejection state of each ink.

(Evaluation criteria)
〇: When the droplet landed in a range within 5 droplets, which is the largest in the front, back, left, and right compared to the normal position:
△: When the droplet is the largest in the front, back, left, and right compared to the normal position, and any of the droplets lands in a deviation range of more than 5 droplets and within 15 droplets. ×: Either the front, back, left, or right of the droplet compared to the normal position. When exceeding 15 droplets

(Examples 7-12, Comparative Examples 7-12)
After filling the Ricoh inkjet head MH5241F with the ink shown in Table 5, in Examples 7 to 12, it was replaced with the cleaning liquid shown in Table 5. In Comparative Examples 7 to 12, the ink was not replaced with the cleaning liquid, and the ink was heated to 30 ° C. After 1, 3, and 5 days of storage, the amount of eluted iron in the filled ink was measured. Table 5 shows the results of the appearance observation of the head after 5 days at 30°C.
(Evaluation criteria)
〇: No change △: Metal parts turned brown ×: Corroded

In addition, the same ejection test as in Example 1 was conducted, and the ink ejection state was evaluated according to the same evaluation criteria as in Example 1.
Table 5 shows the evaluation results.

Embodiments of the present invention are, for example, as follows.
(1) A cleaning solution containing water and an organic solvent containing a compound having 2 or more carbon atoms and 2 or 3 OH groups,
pH is 7 or more and 10 or less,
The concentration of phosphate ions is 100 ppm or more and 5000 ppm or less,
The ratio of the organic solvent in the total amount of the cleaning liquid is 5% by mass or more and 20% by mass or less,
A cleaning liquid, wherein the compound having two or three OH groups accounts for 60% by mass or more and 100% by mass or less in the total amount of the organic solvent.
(2) the compound having 2 or more carbon atoms and 2 or 3 OH groups is selected from the group consisting of propylene glycol, glycerin, 1,2-ethanediol, and dipropylene glycol; The cleaning liquid according to (1) above, which contains at least one of
(3) The cleaning liquid according to (1) or (2) above, wherein the organic solvent contains a compound having an amide group-containing ring structure.
(4) The cleaning liquid according to (3) above, wherein the compound having an amide group-containing ring structure is 2-pyrrolidone and/or ε-caprolactam.
(5) A cleaning liquid and ink set characterized by combining the cleaning liquid according to any one of (1) to (4) above with ink.
(6) A set of the cleaning liquid and ink according to (5) above, wherein the ink is a dye ink.
(7) The cleaning liquid and ink set according to (6) above, wherein the dye in the dye ink is a dye compound having a vinyl sulfone group.
(8) An ink containing container that contains ink, an ink discharge head that discharges the ink, an ink supply path that connects the ink discharge head and the ink container, and the inside of the ink discharge head and the ink supply path a cleaning liquid storage container containing a cleaning liquid for replacing ink in the cleaning liquid storage container; and cleaning liquid supply means for supplying the cleaning liquid in the cleaning liquid storage container to the ink supply path and the ink discharge head,
An inkjet system, wherein the ink and the cleaning liquid are the ink and the cleaning liquid in a set of the cleaning liquid and the dye ink according to any one of (5) to (7) above.
(9) When ink is not continuously supplied to the ejection head within a preset time, the cleaning liquid is supplied to the ink supply path and the ink ejection head to The inkjet system according to (8) above, comprising means for replacing the ink in the ejection head with the cleaning liquid.

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 2011-213846 A JP-A-07-268665

Claims (9)

A cleaning solution containing water and an organic solvent containing a compound having 2 or more carbon atoms and 2 or 3 OH groups,
pH is 7 or more and 10 or less,
The concentration of phosphate ions is 100 ppm or more and 5000 ppm or less,
The ratio of the organic solvent in the total amount of the cleaning liquid is 5% by mass or more and 20% by mass or less,
The cleaning liquid, wherein the ratio of the compound having two or three OH groups in the total amount of the organic solvent is 60% by mass or more and 100% by mass or less. The compound having 2 or more carbon atoms and 2 or 3 OH groups is at least one selected from the group consisting of propylene glycol, glycerin, 1,2-ethanediol, and dipropylene glycol. 2. The cleaning fluid of claim 1, comprising seeds. The cleaning liquid according to claim 1 or 2, wherein the organic solvent contains a compound having an amide group-containing ring structure. 4. The cleaning solution according to claim 3, wherein the compound having an amide group-containing ring structure is 2-pyrrolidone and/or ε-caprolactam. A set of cleaning liquid and ink, characterized by combining the cleaning liquid according to any one of claims 1 to 4 and ink. 6. The cleaning liquid and ink set according to claim 5, wherein the ink is a dye ink. 7. The cleaning liquid and ink set according to claim 6, wherein the dye in the dye ink is a dye compound having a vinyl sulfone group. an ink container containing ink; an ink discharge head for discharging the ink; an ink supply path connecting the ink discharge head and the ink container; and ink in the ink discharge head and the ink supply path. and a cleaning liquid supply means for supplying the cleaning liquid in the cleaning liquid storage container to the ink supply path and the ink ejection head,
An inkjet system, wherein the ink and the cleaning liquid are the ink and the cleaning liquid in a set of the cleaning liquid and the dye ink according to any one of claims 5 to 7. When ink is not continuously supplied to the ejection head within a preset time, the cleaning liquid is supplied to the ink supply path and the ink ejection head to clean the ink supply path and the ink ejection head. 9. The inkjet system of claim 8, comprising means for replacing the ink of the ink with the cleaning liquid.

Images