JP2017136752A - Method for cleaning ink discharge head, device for cleaning the same, recording method and recording device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for cleaning an ink discharge head and the like that can efficiently remove ink fixedly adhering at a nozzle face on an ink discharge side of a nozzle plate of an ink discharge head to keep the nozzle face clean.SOLUTION: A method for cleaning an ink discharge head for cleaning a nozzle face of an ink discharge head includes: a step of imparting cleaning fluid to a wiping member on a pressing member; and a step of wiping the nozzle face with the wiping member imparted with the cleaning fluid. In the method for cleaning an ink discharge head, an amount of the cleaning fluid to be imparted is controlled by recording time.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a method for cleaning an ink discharge head, a cleaning apparatus therefor, a recording method, and a recording apparatus.

  2. Description of the Related Art Conventionally, as a recording apparatus such as a printer, a facsimile machine, a copying apparatus, a plotter, or a complex machine thereof, for example, an ink ejection type recording apparatus having an ink ejection head is known.

In recent years, pigment ink has been increasingly used as an ink used in the ink jet recording apparatus because of its excellent water resistance and light resistance.
Inkjet recording using the pigment ink has been used for commercial printing applications such as a high-speed continuous book machine (for example, see Patent Document 1). In such commercial printing applications, printing media with low ink absorbency are also required as recording media, and image quality equivalent to that of offset printing is required, so improvements have been made to improve ink fixability. ing.
As a result, it has become quite difficult to ensure the ejection reliability of the pigment ink. In particular, pigment ink with improved fixability is likely to adhere to the nozzle surface on the ink ejection side of the nozzle plate of the ink ejection head, and the ink that adheres when wiping the nozzle surface of the nozzle plate using a conventional rubber blade or the like. Is difficult to remove efficiently and cleanly.
Therefore, for example, the pressing member around which the traveling band-shaped liquid absorber is wound is pressed against the nozzle surface of the head, and the pressing member is slid along the nozzle surface of the head, thereby A head cleaning method for wiping and cleaning the nozzle surface with the liquid absorber has been proposed (see, for example, Patent Document 2).

  It is an object of the present invention to provide a method for cleaning an ink discharge head that can efficiently remove the ink fixed to the nozzle surface on the ink discharge side of the nozzle plate of the ink discharge head and can keep the nozzle surface clean. Objective.

The ink discharge head cleaning method of the present invention as a means for solving the above problems is an ink discharge head cleaning method for cleaning the nozzle surface of the ink discharge head,
Applying a cleaning liquid to the wiping member on the pressing member;
Wiping the nozzle surface with a wiping member to which a cleaning liquid is applied, and
The application amount of the cleaning liquid is controlled by the recording time.

  According to the present invention, there is provided an ink discharge head cleaning method capable of efficiently removing ink adhered to the nozzle surface on the ink discharge side of the nozzle plate of the ink discharge head and keeping the nozzle surface clean. Can do.

FIG. 1 is a flowchart illustrating an example of a method for cleaning an ink discharge head according to the present invention. FIG. 2 is a schematic diagram showing an example of the ink discharge head cleaning apparatus of the present invention. FIG. 3A is a schematic cross-sectional view showing an example of the longitudinal direction of the liquid chamber of the ink discharge head. FIG. 3BA is a schematic cross-sectional view illustrating an example of the short direction of the liquid chamber of the ink discharge head. FIG. 4 is a perspective explanatory view showing an example of an ink jet recording apparatus. FIG. 5 is a perspective explanatory view showing an example of a main tank in the ink jet recording apparatus. FIG. 6 is a schematic diagram illustrating an example of image forming means (ink ejection head) of the ink jet recording apparatus.

(Ink discharge head cleaning method and ink discharge head cleaning device)
An ink discharge head cleaning method of the present invention is an ink discharge head cleaning method for cleaning a nozzle surface of an ink discharge head,
A step of applying a cleaning liquid to the wiping member on the pressing member (hereinafter sometimes referred to as a “cleaning liquid applying step”);
A step of wiping the nozzle surface with a wiping member to which a cleaning liquid has been applied (hereinafter sometimes referred to as a “wiping step”),
The application amount of the cleaning liquid is controlled by the recording time, and further includes other steps as necessary.

The ink discharge head cleaning device of the present invention is an ink discharge head cleaning device for cleaning the nozzle surface of the ink discharge head,
Means for applying a cleaning liquid to the wiping member on the pressing member (hereinafter sometimes referred to as “cleaning liquid applying means”);
Means for wiping the nozzle surface with a wiping member to which a cleaning liquid has been applied (hereinafter sometimes referred to as “wiping means”);
The application amount of the cleaning liquid is controlled by the recording time, and further includes other means as necessary.

  The ink discharge head cleaning method of the present invention can be suitably implemented by the ink discharge head cleaning device of the present invention, the cleaning liquid application step can be performed by the cleaning liquid application means, and the wiping step is the wiping process. The other steps can be performed by the other means.

  The ink discharge head cleaning method and the ink discharge head cleaning apparatus according to the present invention is a method in which the conventional ink discharge head cleaning method assumes a case where there is relatively fresh ink on the nozzle surface of the ink discharge head. The purpose is to prevent wiping traces and unwiping residues due to the absorption capacity of the absorber, and when there is a strong fixed ink on the nozzle surface, the knowledge that the nozzle surface is not sufficiently cleaned by the conventional cleaning method It is based on.

In the serial machine, since the carriage on which the ink ejection head is mounted reciprocates on the recording medium, ink is ejected. Therefore, when the carriage returns to the home position side, the nozzle surface can be wiped off quickly.
On the other hand, in the high-speed continuous book machine, the ink ejection head is fixed on the recording medium, and once recording is started, maintenance for wiping the nozzle surface cannot be performed until one-roll recording is completed. Further, the degree of drying of the ink adhering to the nozzle surface changes according to the recording time.
Therefore, in the present invention, the cleaning liquid is applied to the wiping member on the pressing member, and the nozzle surface is wiped with the wiping member to which the cleaning liquid is applied, thereby using the wiping member in which the amount of cleaning liquid applied is optimized. Therefore, even the ink fixed on the nozzle surface can be efficiently removed.

<Cleaning liquid application process and cleaning liquid application means>
The cleaning liquid applying step is a step of applying a cleaning liquid to the wiping member on the pressing member, and is performed by a cleaning liquid applying means.
The pressing member is not particularly limited as long as it is a member capable of pressing the nozzle surface via the wiping member, and can be appropriately selected according to the purpose. For example, a pressing roller, a pressing roller, and a pressing belt A combination, a wiper, a blade, etc. are mentioned. Among these, a pressure roller is preferable.
There is no restriction | limiting in particular as said wiping member, According to the objective, it can select suitably, For example, a nonwoven fabric, cloth, etc. are mentioned. These are preferably wound in a roll shape, and a roll-shaped non-woven fabric is preferable from the viewpoint that dust generation is difficult and reliability is high.

The application amount of the cleaning liquid is controlled by the recording time. In this case, it is preferable that the application amount of the cleaning liquid is selected from a plurality of set values. Examples of the plurality of set values include a cleaning liquid application method (for example, “pressure”, “number of times of application”, “number of application nozzles”).
The application amount of the cleaning liquid is preferably controlled by a pressure applied to a cleaning liquid application nozzle as a cleaning liquid application unit. When the cleaning liquid is applied from a plurality of cleaning liquid application nozzles, it is preferable that the application amount of the cleaning liquid to the wiping member is controlled by the number of the cleaning liquid application nozzles. The amount of the cleaning liquid applied to the wiping member is preferably controlled by the number of times the cleaning liquid is applied from the cleaning liquid application nozzle.

  The cleaning liquid application means is not particularly limited as long as a certain amount of cleaning liquid can be applied, and can be appropriately selected according to the purpose. Examples thereof include a nozzle, a spray, a dispenser, and a coating device.

-Cleaning solution-
The cleaning liquid contains at least one of the compounds represented by the following structural formulas (1) and (2), preferably contains an organic solvent and a surfactant, and further contains other components as necessary. .

Since the compound represented by the structural formula (1) has high moisture retention and high affinity with water, it easily wets the pigment and the hydrophilic group of the resin component contained in the ink and softens the fixed ink. It has the feature that the effect to make is high.
Although the compound represented by the structural formula (2) has a low affinity with water, it easily wets the pigment contained in the ink and the hydrophobic group of the resin component. It is characterized by a high effect of dissolving the pigment.
As the compounds represented by the structural formulas (1) and (2), those appropriately synthesized may be used, or commercially available products may be used. Examples of the commercially available products include Ecamide M100 (Structural Formula (1)) and Ecamide B100 (Structural Formula (2)) manufactured by Idemitsu Kosan Co., Ltd.
The content of the compounds represented by the structural formulas (1) and (2) is not particularly limited and may be appropriately selected depending on the intended purpose, but is 10% by mass or more and 90% by mass with respect to the total amount of the cleaning liquid. The following is preferable, and 50 mass% or more and 80 mass% or less are more preferable. In the preferable numerical range of the content, a high removal effect of the ink fixed on the nozzle surface can be obtained.

The cleaning liquid preferably contains 3-methoxy-3-methyl-1-butanol. Thereby, the nozzle surface of the ink discharge head can be efficiently cleaned.
Since the 3-methoxy-3-methyl-1-butanol has a high effect of swelling the resin, it is considered that the fixed ink swells to easily wipe the fixed ink from the nozzle surface.

-Organic solvent-
There is no restriction | limiting in particular as said organic solvent, Although it can select suitably according to the objective, A water-soluble organic solvent is used suitably.
Examples of the water-soluble organic solvent include ethers such as polyhydric alcohol, polyhydric alcohol alkyl ether, polyhydric alcohol aryl ether, nitrogen-containing heterocyclic compounds, amides, amines, and sulfur-containing compounds.
Specific examples of the water-soluble organic solvent include ethylene glycol, diethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, and 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-hexa Polyhydric alcohols such as diol, ethyl-1,2,4-butanetriol, 1,2,3-butanetriol, 2,2,4-trimethyl-1,3-pentanediol, and petriol; ethylene glycol monoethyl Polyhydric alcohol alkyl ethers such as ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, tetraethylene glycol monomethyl ether, propylene glycol monoethyl ether; ethylene glycol monophenyl ether, ethylene glycol monobenzyl Polyhydric alcohol aryl ethers such as ether; 2-pyrrolidone, N-methyl-2-pyrrolidone, N-hydroxyethyl-2- Nitrogen-containing heterocyclic compounds such as loridone, 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, Carbonic acid Examples include ethylene. These may be used individually by 1 type and may use 2 or more types together.

Furthermore, a polyol compound having 8 or more carbon atoms and a glycol ether compound can be used in combination. Specific examples of the polyol compound having 8 or more carbon atoms include 2-ethyl-1,3-hexanediol, 2,2,4-trimethyl-1,3-pentanediol, and the like. By containing these, the permeability of the cleaning liquid is improved.
Examples of the glycol ether compound include polyhydric alcohol alkyls 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. Examples of ethers include polyhydric alcohol aryl ethers such as ethylene glycol monophenyl ether and ethylene glycol monobenzyl ether.

--Surfactant--
The cleaning liquid contains a surfactant, so that the cleaning liquid applied to the pressing member is more easily wetted with respect to the ink fixed to the nozzle surface and the nozzle surface, and further to the interface between the fixed ink and the nozzle surface. Since the penetrating power to penetrate can be improved, the nozzle surface can be wiped more effectively.
Examples of the surfactant include silicone surfactants, fluorine surfactants, amphoteric surfactants, nonionic surfactants, and anionic surfactants. These may be used alone or in combination of two or more.

  The silicone-based surfactant is not particularly limited and may be appropriately selected depending on the intended purpose. However, those that do not decompose even at high pH are preferable. For example, side chain-modified polydimethylsiloxane, both-end-modified polydimethylsiloxane , One-end-modified polydimethylsiloxane, side-chain both-end-modified polydimethylsiloxane, and the like. Those having a polyoxyethylene group or a polyoxyethylene polyoxypropylene group as a modifying group are particularly preferred because they exhibit good properties as an aqueous surfactant. In addition, as the silicone surfactant, a polyether-modified silicone surfactant can be used, and examples thereof include a compound in which a polyalkylene oxide structure is introduced into the Si portion side chain of dimethylsiloxane.

Examples of the fluorosurfactant include a perfluoroalkyl sulfonic acid compound, a perfluoroalkyl carboxylic acid compound, a perfluoroalkyl phosphate ester compound, a perfluoroalkyl ethylene oxide adduct, and a perfluoroalkyl ether group in the side chain. The polyoxyalkylene ether polymer compound is particularly preferred because of its low foamability. Examples of the perfluoroalkyl sulfonic acid compound include perfluoroalkyl sulfonic acid and perfluoroalkyl sulfonate. Examples of the perfluoroalkyl carboxylic acid compound include perfluoroalkyl carboxylic acid and perfluoroalkyl carboxylate. Examples of the polyoxyalkylene ether polymer compound having a perfluoroalkyl ether group in the side chain include, for example, a sulfate ester salt of a polyoxyalkylene ether polymer having a perfluoroalkyl ether group in the side chain, and a perfluoroalkyl ether group in the side chain. And salts of polyoxyalkylene ether polymers possessed by Examples of the salt counter ion in these fluorosurfactants include Li, Na, K, NH ₄ , NH ₃ CH ₂ CH ₂ OH, NH ₂ (CH ₂ CH ₂ OH) ₂ , NH (CH ₂ CH ₂ OH) _{3 and the} like.

Examples of the amphoteric surfactant include lauryl aminopropionate, lauryl dimethyl betaine, stearyl dimethyl betaine, and lauryl dihydroxyethyl betaine.
Examples of the nonionic surfactant include polyoxyethylene alkylphenyl ether, polyoxyethylene alkyl ester, polyoxyethylene alkylamine, polyoxyethylene alkylamide, polyoxyethylene propylene block polymer, sorbitan fatty acid ester, polyoxyethylene. Examples include sorbitan fatty acid esters and ethylene oxide adducts of acetylene alcohol.
Examples of the anionic surfactant include polyoxyethylene alkyl ether acetates, dodecylbenzene sulfonates, launrilates, polyoxyethylene alkyl ether sulfate salts, and the like.

-Other ingredients-
Examples of the other components include pH adjusters and antiseptic / antifungal agents.
There is no restriction | limiting in particular as said pH adjuster, According to the objective, it can select suitably, For example, hydroxide of alkali metals, such as lithium hydroxide, sodium hydroxide, potassium hydroxide; Lithium carbonate, sodium carbonate And carbonates of alkali metals such as potassium carbonate; quaternary ammonium hydroxides; amines such as diethanolamine and triethanolamine; ammonium hydroxide; quaternary phosphonium hydroxides and the like.

  The antiseptic / antifungal agent is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include 1,2-benzisothiazolin-3-one, sodium benzoate, sodium dehydroacetate, sodium sorbate, penta Examples include sodium chlorophenol and sodium 2-pyridinethiol-1-oxide.

<Wiping process and wiping means>
The wiping step is a step of wiping the nozzle surface with a wiping member to which a cleaning liquid is applied, and is preferably carried out by wiping means.
The method for wiping the nozzle surface with the wiping member to which the cleaning liquid has been applied is not particularly limited and can be appropriately selected according to the purpose. For example, a nonwoven fabric as the wiping member to which the cleaning liquid has been applied is used as the pressing member. For example, a method of pressing the nozzle surface of the ink discharge head with a pressing roller may be used.

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

Here, FIG. 1 is a flowchart showing an example of the method of cleaning the ink discharge head of the present invention.
First, recording is performed by ejecting ink from the nozzle surface on the ink ejection side of the nozzle plate of the ink ejection head. In the case of continuous recording, the recording time Tp is obtained from recording start (T0) -recording end (T1). In the case of intermittent recording, the recording time Tp can be obtained from the total of the individual recording times.
The recording time (X, Y) and the setting of the cleaning liquid application amount when selecting the stage of the cleaning liquid application amount can be changed depending on the ink and the cleaning liquid to be used. Moreover, it is preferable to select from a plurality of set amounts such as a normal amount and a large amount or a small amount and a normal amount.
The application amount of the cleaning liquid depends on the type of ink used and the setting of the recording time (X, Y), but is preferably 0.05 mL / cm ² or more and less than 1 mL / cm ² as a small amount, and the medium speed is 1 mL / cm ^2. It is preferably cm ² or more and less than 0.3 mL / cm ² , and the high speed is preferably 0.3 mL / cm ² or more.
In applying the cleaning liquid, pressure is applied to the cleaning liquid application nozzle, and the application amount of the cleaning liquid can be adjusted to a desired amount by changing the pressure (selection of pressure). In addition, it is possible to adjust the application amount of the cleaning liquid by changing the number of nozzles applied by the plurality of cleaning liquid application nozzles (select the number of nozzles), and further change the number of times the cleaning liquid is applied from the cleaning liquid application nozzle (the number of application times of cleaning liquid The amount of application can be adjusted (selection of the number of applications).
Next, the nozzle surface after recording is wiped using the wiping member to which the cleaning liquid is applied.
This completes the cleaning of the nozzle surface on the ink discharge side of the nozzle plate of the ink discharge head.

Here, FIG. 2 is a schematic view showing an example of the cleaning apparatus for the ink discharge head of the present invention. The cleaning device 300 in FIG. 2 is a device that cleans the nozzle surface 301a on the ink discharge side of the nozzle plate 301 of the ink discharge head.
The cleaning apparatus 300 includes a nonwoven fabric 303 as a wiping member, a cleaning liquid application nozzle 302 as a cleaning liquid application unit, a pressing roller 305 as a pressing member, and a take-up roller 304 that winds up the nonwoven fabric after the wiping process. Yes.
The cleaning liquid is supplied from the cleaning liquid tank via a cleaning liquid supply tube (not shown). By driving a pump provided in the middle of the cleaning liquid supply tube, the cleaning liquid is applied from the cleaning liquid application nozzle 302 to the non-woven fabric 303 as the wiping member in an application amount of the cleaning liquid according to the recording time. The nonwoven fabric 303 is wound in a roll shape.
As shown in FIG. 2, the non-woven fabric 303 to which the cleaning liquid is applied comes into contact with and is pressed against the nozzle surface 301a of the ink discharge head 301 by a pressing roller 305 as a pressing member, thereby cleaning the nozzle surface 301a. After the wiping process is completed, the nonwoven fabric 303 is taken up by the take-up roller 304.
A plurality of cleaning liquid application nozzles 302 as cleaning liquid application means can be provided, and pressure is applied based on control of a control means (not shown), and the application amount of the cleaning liquid can be changed by appropriately changing the pressure. Can be adjusted. Further, the amount of the cleaning liquid applied can be adjusted by changing the number of nozzles to which the cleaning liquid is applied based on the control of the control means (not shown). Furthermore, the application amount of the cleaning liquid can be adjusted by changing the number of times of applying the cleaning liquid based on the control of the control means (not shown).

<< Ink ejection head >>
The ink discharge head has a nozzle plate, and further includes other members as necessary.

-Nozzle plate-
The nozzle plate includes a nozzle substrate and an ink repellent film on the nozzle substrate.

-Nozzle substrate-
Nozzle holes are provided in the nozzle substrate, and the number, shape, size, material, structure, etc. thereof are not particularly limited and can be appropriately selected according to the purpose.
The nozzle substrate has an ink ejection side nozzle surface from which ink is ejected from the nozzle holes, and a liquid chamber joining surface located on the opposite side of the ink ejection side surface.
The ink repellent film is formed on the nozzle surface of the nozzle substrate on the ink ejection side.

There is no restriction | limiting in particular as a planar shape of the said nozzle substrate, According to the objective, it can select suitably, For example, a rectangle, a square, a rhombus, a circle, an ellipse etc. are mentioned. Examples of the cross-sectional shape of the nozzle substrate include a flat plate shape and a plate shape.
There is no restriction | limiting in particular as a magnitude | size of the said nozzle substrate, According to the magnitude | size of the said nozzle plate, it can select suitably.

Examples of the material of the nozzle substrate is not particularly limited and may be appropriately selected depending on the purpose, for example, stainless steel, Al, Bi, Cr, InSn , ITO, Nb, Nb 2 O 5, NiCr, Si, _{SiO 2, Sn, Ta 2 O} 5, Ti, W, ZAO (ZnO + Al 2 O 3), Zn and the like. These may be used alone or in combination of two or more. Among these, stainless steel is preferable from the viewpoint of rust prevention.

-Nozzle hole-
The number, arrangement, interval, opening shape, opening size, opening cross-sectional shape, and the like of the nozzle holes are not particularly limited and can be appropriately selected depending on the purpose.
The arrangement of the nozzle holes is not particularly limited and may be appropriately selected depending on the purpose. For example, the plurality of nozzle holes are arranged at regular intervals along the length direction of the nozzle substrate. And the like.
The arrangement of the nozzle holes can be appropriately selected according to the type of ink to be ejected, but it is preferably 1 or more and 2 or less, more preferably 1 or more and 4 or less.
There is no restriction | limiting in particular as the number of the said nozzle holes per said line, Although it selects suitably according to the objective, 10 or more and 10,000 or less are preferable, and 50 or more and 500 or less are more preferable.
The interval (pitch) P, which is the shortest distance between the centers of adjacent nozzle holes, is not particularly limited and may be appropriately selected depending on the intended purpose. For example, it is preferably 21 μm or more and 169 μm or less.
There is no restriction | limiting in particular as an opening shape of the said nozzle hole, According to the objective, it can select suitably, For example, circular, an ellipse, a square etc. are mentioned. Among these, a circular shape is preferable from the viewpoint of discharging ink droplets.

-Ink-repellent film-
The ink repellent film is formed on the nozzle surface on the ink ejection side having the plurality of recesses in the nozzle substrate, and there is no particular limitation on the shape, structure, material, thickness, etc., depending on the purpose. It can be selected appropriately.

  The material of the ink repellent film is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include silicone resins and perfluoropolyether compounds from the viewpoint of excellent water repellency with respect to ink.

-Other components-
There is no restriction | limiting in particular as said other member, According to the objective, it can select suitably, For example, a pressurization chamber, a stimulus generation means, etc. are mentioned.

--- Pressurization chamber--
The pressurizing chamber is a plurality of individual flow paths that are individually disposed corresponding to the plurality of nozzle holes provided in the nozzle plate and communicate with the nozzle holes, and include an ink flow path, a pressurized liquid chamber, It may be called a pressure chamber, a discharge chamber, a liquid chamber, etc.

--Stimulus generation means--
The stimulus generating means is means for generating a stimulus to be applied to ink.
There is no restriction | limiting in particular as a stimulus in the said stimulus generation means, According to the objective, it can select suitably, For example, heat | fever (temperature), a pressure, a vibration, light etc. are mentioned. These may be used individually by 1 type and may use 2 or more types together. Among these, heat and pressure are preferable.
Examples of the stimulus generating means include a heating device, a pressurizing device, a piezoelectric element, a vibration generating device, an ultrasonic oscillator, and a light. Specifically, as the stimulus generating means, a piezoelectric actuator such as a piezoelectric element, a thermal actuator that uses a phase change caused by film boiling of ink using an electrothermal transducer such as a heating resistor, a metal phase change caused by a temperature change Shape memory alloy actuators using electrostatic force, electrostatic actuators using electrostatic force, and the like.

When the stimulus is “heat”, thermal energy corresponding to the recording signal is applied to the ink in the ink ejection head using, for example, a thermal head. Examples include a method in which bubbles are generated in the ink by the thermal energy, and the ink is ejected as droplets from the nozzle holes of the nozzle plate by the pressure of the bubbles.
When the stimulus is “pressure”, for example, the piezoelectric element is bent by applying a voltage to the piezoelectric element bonded to the position called the pressure chamber in the ink flow path in the ink discharge head. . As a result, the volume of the pressure chamber shrinks, and the ink is ejected as droplets from the nozzle holes of the ink ejection head.
Among these, a piezo method in which a voltage is applied to the piezo element to fly ink is preferable.

Here, an example of the ink ejection head used in the present invention will be described with reference to the drawings.
3A and 3B are schematic views for explaining an example of the cross-sectional shape of the ink discharge head.
More specifically, FIG. 3A is a schematic cross-sectional view illustrating an example of a flow path (a cross section in the longitudinal direction of the liquid chamber 40F) of the image forming unit 40, and FIG. 3B is a schematic view of an ejection port 40N of the image forming unit 40. It is sectional drawing which shows arrangement | positioning (cross section (SC1 of FIG. 3A)) of the transversal direction (arrangement direction of a discharge outlet) of the liquid chamber 40F.

  As shown in FIG. 3A, the ink discharge head (40K, etc.) of the image forming means 40 is bonded to the flow path plate 41 that forms the path of the ink to be discharged, and the lower surface of the flow path plate 41 (inner direction of the discharge head). The vibration plate 42, the nozzle plate 43 joined to the upper surface of the flow path plate 41 (outward direction of the ejection head), and a frame member 44 that holds the peripheral edge of the vibration plate 42. In addition, the ink discharge head has a pressure generating means (actuator means) 45 for deforming the vibration plate 42.

In the present embodiment, the ink discharge head includes a plurality of discharge ports (nozzles, print nozzles) 40N on the nozzle surface (the outer surface of the nozzle plate 43). Here, the plurality of ejection ports 40N are arranged in one row in the longitudinal direction of the ink ejection head 40K-1, and constitute a nozzle row. The ink ejection head 40K-1 may include a plurality of nozzle rows.
The ink discharge head (40K, etc.) includes a flow path plate 41, a vibration plate 42, and a nozzle plate 43, and a nozzle communication path 40R that is a flow path communicating with the discharge port (nozzle) 40N and a liquid chamber. 40F can be formed. Further, the ejection head can form the ink inlet 40S for supplying ink to the liquid chamber 40F, the common liquid chamber 40C for supplying ink to the liquid chamber 40F, and the like by further stacking the frame members 44. .
Further, the ink ejection head can deform (bend deformation) the vibration plate 42 using the pressure generating means 45. Thereby, the ink discharge head can change the volume (volume) of the liquid chamber 40F and change the pressure acting on the ink in the liquid chamber 40F. As a result, the ink discharge head can discharge ink from the discharge port 40N.

  As the flow path plate 41, for example, a single crystal silicon substrate having a crystal plane orientation (110) can be used. As a result, the flow path plate 41 is anisotropically etched using an alkaline etching solution such as an aqueous potassium hydroxide solution (KOH), thereby forming a recess and a hole serving as the nozzle communication path 40R and the liquid chamber 40F. be able to. The material that can be used for the flow path plate 41 is not limited to the single crystal silicon substrate. That is, the flow path plate 41 can use a stainless steel substrate, a photosensitive resin, and other materials.

As the diaphragm 42, for example, a nickel metal plate can be used. Thereby, the diaphragm 42 can be processed by nickel electroforming (for example, electroforming method, electroforming method). The vibration plate 42 may be a metal plate other than a nickel metal plate or a bonding member between a metal and a resin plate.
As the nozzle plate 43, for example, a single crystal silicon substrate can be used. Thereby, the nozzle plate 43 can be processed by anisotropic etching in the same manner as the flow path plate 41. The nozzle plate 43 may be formed with a water repellent layer on a contour surface made of a metal member via a required layer.
The nozzle plate 43 includes a plurality of nozzles 40N that eject ink droplets. Specifically, the nozzle plate 43 is formed with nozzles 40N having a diameter of 10 μm to 30 μm corresponding to the respective liquid chambers 40F.
As the frame member 44, for example, a thermosetting resin (for example, epoxy resin) or polyphenylene sulfite (PPS) can be used. Thereby, the frame member 44 can be processed by injection molding.
Further, the frame member 44 is formed with an accommodating portion for accommodating the pressure generating means 45, a concave portion serving as the common liquid chamber 40C, and an ink supply port 40IN for supplying ink to the common liquid chamber 40C from the outside of the ejection head.

As the pressure generating means 45, an electromechanical conversion element can be used. The pressure generating means 45 includes a piezoelectric element 45P that is an electromechanical conversion element, a base substrate 45B to which the piezoelectric element 45P is bonded and fixed, and a column portion that is disposed in a gap between adjacent piezoelectric elements 45P. The pressure generating means 45 includes an FPC cable 45C for connecting the piezoelectric element 45P to a drive circuit (drive IC) (not shown).
Here, as shown in FIG. 3B, the piezoelectric element 45P may be a stacked piezoelectric element (PZT) in which piezoelectric materials 45Pp and internal electrodes 45Pe are alternately stacked.
The internal electrode 45Pe has a plurality of individual electrodes 45Pei and a plurality of common electrodes 45Pec. The internal electrode 45Pe connects the individual electrode 45Pei or the common electrode 45Pec alternately to the end face of the piezoelectric element 45Pp.
In the embodiment, the piezoelectric element 45P uses the d33 direction as the piezoelectric direction of the piezoelectric element 45Pp. Thereby, the pressure generating means 45 can pressurize or depressurize the ink in the liquid chamber 40F using the piezoelectric effect (displacement in the d33 direction) of the piezoelectric element 45P. The pressure generating means 45 may pressurize or depressurize the ink in the liquid chamber 40F using the displacement of the piezoelectric element 45P in the d31 direction. Further, the pressure generating means 45 may arrange one row of piezoelectric elements for one discharge port 40N.
In addition, you may form a support | pillar part simultaneously with the piezoelectric element 45P by dividing | segmenting a piezoelectric element member (piezoelectric element 45P). That is, the ink ejection head can use the piezoelectric element member as a support portion by applying no voltage to the piezoelectric element.

Hereinafter, the operation of the ink ejection head ejecting ink from the nozzles 40N (drawing-pushing operation) will be specifically described.
First, the ink discharge head lowers the voltage applied to the piezoelectric element 45P (pressure generating means 45) from the reference potential, and reduces the piezoelectric element 45P in the stacking direction. Further, the ink ejection head flexes and deforms the vibration plate 42 by reducing the piezoelectric element 45P. At this time, the ink ejection head expands (expands) the volume (volume) of the liquid chamber 40 </ b> F by the bending deformation of the vibration plate 42. Accordingly, the ink discharge head can cause ink to flow into the liquid chamber 40F from the common liquid chamber 40C.
Next, the ink ejection head increases the voltage applied to the piezoelectric element 45P, and extends the piezoelectric element 45P in the stacking direction. Further, the ink ejection head deforms the vibration plate 42 in the direction of the nozzle 40N by the extension of the piezoelectric element 45P. At this time, the ink discharge head reduces (contracts) the volume (volume) of the liquid chamber 40F by the deformation of the vibration plate 42. Thereby, the ink discharge head can apply pressure to the ink in the liquid chamber 40F. The ink ejection head can eject (eject) ink from the ejection port 40N by pressurizing the ink.
Thereafter, the ink discharge head returns the voltage applied to the piezoelectric element 45P to the reference potential, and returns (restores) the diaphragm 42 to the initial position. At this time, the ink discharge head depressurizes the liquid chamber 40F due to the expansion of the liquid chamber 40F, and fills (replenishes) ink from the common liquid chamber 40C to the liquid chamber 40F. Next, after the vibration of the meniscus surface of the nozzle 40N is attenuated (stable), the ink discharge head shifts to an operation for discharging the next ink, and repeats the above operation.
The method for driving the ink ejection head that can be used in the present invention is not limited to the above example (pull-push). That is, the driving method of the ink discharge head can perform striking or pushing by controlling the voltage (driving waveform) applied to the piezoelectric element 45P.

(Recording method and recording apparatus)
The recording method of the present invention includes a discharge step of discharging ink from the nozzle surface on the ink discharge side of the nozzle plate of the ink discharge head, a cleaning step of cleaning the nozzle surface by the cleaning method of the ink discharge head of the present invention, In addition, other steps are included as necessary.

  The recording apparatus of the present invention has an ink discharge head for discharging ink, and the cleaning apparatus for the ink discharge head of the present invention for cleaning the nozzle surface on the ink discharge side of the nozzle plate of the ink discharge head, Furthermore, it has other means as needed.

<Ink>
Hereinafter, the organic solvent, water, color material, resin, additive, and the like used for the ink will be described.

<Organic solvent>
The organic solvent used in the present invention is not particularly limited, and a water-soluble organic solvent can be used. Examples thereof include ethers such as polyhydric alcohols, polyhydric alcohol alkyl ethers and polyhydric alcohol aryl ethers, nitrogen-containing heterocyclic compounds, amides, amines and sulfur-containing compounds.
Specific examples of the water-soluble organic solvent include, for example, ethylene glycol, diethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, and 1,4-butane. Diol, 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-he Polyhydric alcohols such as sundiol, ethyl-1,2,4-butanetriol, 1,2,3-butanetriol, 2,2,4-trimethyl-1,3-pentanediol, petriol, ethylene glycol mono Polyhydric alcohol alkyl ethers such as ethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, tetraethylene glycol monomethyl ether, propylene glycol monoethyl ether, ethylene glycol monophenyl ether, ethylene glycol mono Polyhydric alcohol aryl ethers such as benzyl ether, 2-pyrrolidone, N-methyl-2-pyrrolidone, N-hydroxyethyl- -N-containing heterocyclic compounds such as pyrrolidone, 1,3-dimethyl-2-imidazolidinone, ε-caprolactam, γ-butyrolactone, formamide, N-methylformamide, N, N-dimethylformamide, 3-methoxy-N, Amides such as N-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, Examples thereof include ethylene carbonate.
In addition to functioning as a wetting agent, it is preferable to use an organic solvent having a boiling point of 250 ° C. or lower because good drying properties can be obtained.

<Color material>
The color 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 alone or in combination of two or more. A mixed crystal may be used.
As the pigment, for example, a black pigment, a yellow pigment, a magenta pigment, a cyan pigment, a white pigment, a green pigment, an orange pigment, a glossy pigment such as gold or silver, a metallic pigment, or the like can be used.
Carbon black produced by known methods such as contact method, furnace method, thermal method in addition to titanium oxide, iron oxide, calcium carbonate, barium sulfate, aluminum hydroxide, barium yellow, cadmium red, chrome yellow as inorganic pigments Can be used.
Organic pigments include azo pigments, polycyclic pigments (for example, phthalocyanine pigments, perylene pigments, perinone pigments, anthraquinone pigments, quinacridone pigments, dioxazine pigments, indigo pigments, thioindigo pigments, isoindolinone pigments, quinofullerone pigments, etc.) Dye chelates (for example, basic dye type chelates, acidic dye type chelates), nitro pigments, nitroso pigments, aniline black, and the like can be used. Of 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 include black for carbon black (CI pigment black 7) such as furnace black, lamp black, acetylene black, channel black, or copper, iron (CI pigment black 11). And organic pigments such as metals such as titanium oxide and aniline black (CI Pigment Black 1).
Further, for color use, 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, 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 (Bengara), 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 dye is not particularly limited, and an acid dye, a direct dye, a reactive dye, and a basic dye can be used. One kind may be used alone, or two or more kinds may be used in combination.
Examples of the dye include 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, and 35 are mentioned.

  The content of the color material in the ink is preferably 0.1% by mass or more and 15% by mass or less, more preferably 1% by mass or more and 10% by mass from the viewpoints of improvement in image density, good fixability and ejection stability. It is as follows.

In order to disperse the pigment in the ink, a method of introducing a hydrophilic functional group into the pigment to form a self-dispersing pigment, a method of dispersing the pigment surface by coating with a resin, a method of dispersing using a dispersant, Etc.
Examples of a method for introducing a hydrophilic functional group into a pigment to form a self-dispersing pigment include a self-dispersing pigment that can be dispersed in water by adding a functional group such as a sulfone group or a carboxyl group to the pigment (for example, carbon). Can be used.
As a method for coating the surface of the pigment with a resin and dispersing it, a method in which the pigment is included in microcapsules and can be dispersed in water can be used. This can be paraphrased as a resin-coated pigment. In this case, it is not necessary that all pigments blended in the ink are coated with a resin, and within a range where the effects of the present invention are not impaired, uncoated pigments and partially coated pigments are dispersed in the ink. It may be.
Examples of the method of dispersing using a dispersant include a method of dispersing using a known low-molecular type dispersant or high-molecular type dispersant represented by a surfactant.
As the dispersant, for example, an anionic surfactant, a cationic surfactant, an amphoteric surfactant, a nonionic surfactant, or the like can be used depending on the pigment.
RT-100 (nonionic surfactant) manufactured by Takemoto Yushi Co., Ltd. and naphthalenesulfonic acid Na 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>
An ink can be obtained by mixing a material such as water or an organic solvent with a color material. Further, it is also possible to produce an ink by mixing a pigment, other water, a dispersant, and the like into a pigment dispersion and mixing a material such as water or an organic solvent.
The pigment dispersion is obtained by dispersing water, a pigment, a pigment dispersant, and other components as required, and adjusting the particle size. For dispersion, a disperser is preferably used.
The particle diameter of the pigment in the pigment dispersion is not particularly limited, but the maximum frequency is 20 nm or more in terms of maximum number because the pigment dispersion stability is good and the image quality such as ejection stability and image density is also high. 500 nm or less is preferable and 20 nm or more and 150 nm or less are 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 may be appropriately selected depending on the intended purpose. However, from the viewpoint of obtaining good ejection stability and increasing the image density, 0.1% by mass. % To 50% by mass is preferable, and 0.1% to 30% by mass is more preferable.
The pigment dispersion is preferably degassed by filtering coarse particles with a filter, a centrifugal separator or the like, if necessary.

<Resin>
The type of resin contained in the ink is not particularly limited and can be appropriately selected according to the purpose. For example, urethane resin, polyester resin, acrylic resin, vinyl acetate resin, styrene resin, butadiene type Examples thereof include resins, styrene-butadiene resins, vinyl chloride resins, acrylic styrene resins, and acrylic silicone resins.
Resin particles made of these resins may be used. An ink can be obtained by mixing resin particles with a material such as a colorant or an organic solvent in a resin emulsion state in which water is dispersed as a dispersion medium. As said resin particle, what was synthesize | combined suitably may be used and a commercial item may be used. These may be used alone or in combination of two or more kinds of resin particles.

  The resin content is not particularly limited and may be appropriately selected according to the purpose. However, from the viewpoint of fixability and ink storage stability, the content of the resin is 1% by mass or more and 30% by mass or less. Is preferable, and 5 mass% or more and 20 mass% or less are more preferable.

  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 the image quality such as ejection stability and image density, the maximum frequency in terms of the maximum number is converted. Is preferably 20 nm to 1000 nm, and more preferably 20 nm to 150 nm. 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.).

<Additives>
If necessary, a surfactant, an antifoaming agent, an antiseptic / antifungal agent, an antirust agent, a pH adjuster, and the like may be added to the ink.

<Surfactant>
As the surfactant, any of silicone surfactants, fluorine surfactants, amphoteric surfactants, nonionic surfactants and anionic surfactants can be used.
There is no restriction | limiting in particular as a silicone type surfactant, According to the objective, it can select suitably. Among them, those that do not decompose even at high pH are preferable, and examples thereof include side chain modified polydimethylsiloxane, both terminal modified polydimethylsiloxane, one terminal modified polydimethylsiloxane, and side chain both terminal modified polydimethylsiloxane. Those having an oxyethylene group or a polyoxyethylene polyoxypropylene group are particularly preferred because they exhibit good properties as an aqueous surfactant. In addition, as the silicone surfactant, a polyether-modified silicone surfactant can be used, and examples thereof include a compound in which a polyalkylene oxide structure is introduced into the side chain of the Si portion of dimethylsiloxane.
Examples of the fluorosurfactant include a perfluoroalkyl sulfonic acid compound, a perfluoroalkyl carboxylic acid compound, a perfluoroalkyl phosphate compound, a perfluoroalkyl ethylene oxide adduct, and a perfluoroalkyl ether group in the side chain. Polyoxyalkylene ether polymer compounds are particularly preferred because of their low foaming properties. Examples of the perfluoroalkyl sulfonic acid compound include perfluoroalkyl sulfonic acid, perfluoroalkyl sulfonate, and the like. Examples of the perfluoroalkylcarboxylic acid compound include perfluoroalkylcarboxylic acid and perfluoroalkylcarboxylate. Examples of the polyoxyalkylene ether polymer compound having a perfluoroalkyl ether group in the side chain include a sulfate ester salt of a polyoxyalkylene ether polymer having a perfluoroalkyl ether group in the side chain and a perfluoroalkyl ether group in the side chain. Examples thereof include salts of polyoxyalkylene ether polymers. As counter ions of salts in these fluorosurfactants, Li, Na, K, NH ₄ , NH ₃ CH ₂ CH ₂ OH, NH ₂ (CH ₂ CH ₂ OH) ₂ , NH (CH ₂ CH ₂ OH) ₃ etc. are mentioned.
Examples of amphoteric surfactants include lauryl aminopropionate, lauryl dimethyl betaine, stearyl dimethyl betaine, and lauryl dihydroxyethyl betaine.
Nonionic surfactants include, for example, polyoxyethylene alkylphenyl ether, polyoxyethylene alkyl ester, polyoxyethylene alkylamine, polyoxyethylene alkylamide, polyoxyethylene propylene block polymer, sorbitan fatty acid ester, polyoxyethylene sorbitan Examples include fatty acid esters and ethylene oxide adducts of acetylene alcohol.
Examples of the anionic surfactant include polyoxyethylene alkyl ether acetate, dodecylbenzene sulfonate, laurate, polyoxyethylene alkyl ether sulfate salt, and the like.
These may be used alone or in combination of two or more.

  There is no restriction | limiting in particular as content of surfactant in an ink, Although it can select suitably according to the objective, From the point which is excellent in wettability and discharge stability, and image quality improves, it is 0.001 mass. % To 5% by mass is preferable, and 0.05% to 5% by mass is more preferable.

<Antifoaming agent>
There is no restriction | limiting in particular as an antifoamer, For example, a silicone type antifoamer, a polyether type | system | group antifoamer, a fatty-acid ester type | system | group antifoamer etc. are mentioned. These may be used alone or in combination of two or more. Among these, a silicone type antifoaming agent is preferable from the viewpoint of excellent foam breaking effect.

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

<Rust preventive>
There is no restriction | limiting in particular as a rust preventive agent, For example, acidic sulfite, sodium thiosulfate, etc. are mentioned.

<PH adjuster>
The pH adjuster is not particularly limited as long as the pH can be adjusted to 7 or more, and examples thereof include amines such as diethanolamine and triethanolamine.

<Recording apparatus and recording method>
The ink of the present invention can be suitably used for various recording apparatuses using an ink jet recording method, such as a printer, a facsimile apparatus, a copying apparatus, a printer / fax / copier complex machine, and a three-dimensional modeling apparatus.
In the present invention, the recording apparatus and the recording method are an apparatus capable of ejecting ink, various treatment liquids, and the like to a recording medium, and a method of performing recording using the apparatus. The recording medium means a medium on which ink or various processing liquids can be temporarily attached.
The recording apparatus can include not only a head portion that ejects ink but also means for feeding, transporting, and discharging a recording medium, and other devices called pre-processing devices and post-processing devices. .
The recording apparatus and the recording method may include a heating unit used in the heating step and a drying unit used in the drying step. The heating means and the drying means include, for example, a means for heating and drying the printing surface and the back surface of the recording medium. Although it does not specifically limit as a heating means and a drying means, For example, a warm air heater and an infrared heater can be used. Heating and drying can be performed before printing, during printing, after printing, and the like.
Further, the recording apparatus and the recording method are not limited to those in which significant images such as characters and figures are visualized by ink. For example, what forms patterns, such as a geometric pattern, etc. includes what forms a three-dimensional image.
Further, the recording apparatus includes both a serial type apparatus that moves the ejection head and a line type apparatus that does not move the ejection head, unless otherwise specified.
Furthermore, this recording apparatus can use not only a desktop type but also a wide recording apparatus that can print on an A0 size recording medium, for example, a continuous paper wound up in a roll shape as a recording medium. Also included are continuous paper printers.

An example of the recording apparatus will be described with reference to FIGS. FIG. 4 is an explanatory perspective view of the apparatus. FIG. 5 is a perspective view of the main tank. An image forming apparatus 400 as an example of a recording apparatus is a serial type image forming apparatus. A mechanism unit 420 is provided in the exterior 401 of the image forming apparatus 400. Each ink storage portion 411 of the main tank 410 (410k, 410c, 410m, 410y) for each color of black (K), cyan (C), magenta (M), and yellow (Y) is, for example, an aluminum laminate film or the like. It is formed of a packaging member. The ink storage unit 411 is stored in, for example, a plastic container case 414. As a result, 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 inner 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. Thus, the ink discharge ports 413 of the main tank 410 and the discharge heads 434 for the respective colors communicate with each other via the supply tubes 436 for the respective colors, and ink can be discharged from the discharge heads 434 to the recording medium.

Here, FIG. 6 is a schematic view showing an example of the image forming means. The image forming unit in FIG. 6 is a full-line type head. The image forming unit includes black (K), cyan (C), magenta (M), and yellow (from the upstream side in the recording medium conveyance direction Xm). Four discharge heads 40K, 40C, 40M and 40Y corresponding to Y) are arranged.
Here, the black (K) ink discharge head 40K has four head units 40K-1, 40K-2, 40K-3, and 40K-4 arranged in a staggered manner in a direction perpendicular to the transport direction Xm of the roll paper Md. doing. As a result, the image forming unit can form an image in the entire width direction (direction perpendicular to the transport direction) of the image forming area (printing area) of the roll paper Md (recording medium).

As described above, the image forming apparatus 400 uses the image forming unit 40 (the four ejection heads 40K, 40C, 40M, and 40Y) to perform the entire recording medium (roll paper Md) in one transport operation. In addition, a black and white or full color image can be formed.
The pressure generating means 45 is not limited to the above example (piezoelectric element 45P). That is, the pressure generating means 45 is a method of generating bubbles by heating ink in the liquid chamber 40F using a heating resistor (so-called thermal type) (see, for example, JP-A-61-59911). It may be used. Further, the pressure generating means 45 is a method (so-called electrostatic type) in which the diaphragm and the electrode are arranged opposite to each other on the wall surface of the liquid chamber 40F, and the diaphragm is deformed by the electrostatic force generated between the diaphragm and the electrode. May be used (for example, see JP-A-6-71882).

  EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, this invention is not limited to the following Example.

(Example of polymer solution preparation)
-Preparation of polymer solution-
After replacing the inside of a 1 L flask equipped with a mechanical stirrer, thermometer, nitrogen gas inlet tube, reflux tube, and dropping funnel with nitrogen gas, 11.2 g of styrene, 2.8 g of acrylic acid, 12 g of lauryl methacrylate, polyethylene glycol 4 g of methacrylate, 4 g of styrene macromer (manufactured by Toa Gosei Co., Ltd., trade name: AS-6), 0.4 g of mercaptoethanol, and 40 g of methyl ethyl ketone were added, and the temperature was raised to 65 ° C.
Next, 100.8 g of styrene, 25.2 g of acrylic acid, 108 g of lauryl methacrylate, 36 g of polyethylene glycol methacrylate, 60 g of hydroxyl ethyl methacrylate, 36 g of styrene macromer (trade name: AS-6, manufactured by Toa Gosei Co., Ltd.), mercaptoethanol 3. A mixed solution of 6 g, azobismethylvaleronitrile 2.4 g, and methyl ethyl ketone 342 g was dropped into the flask over 2.5 hours. Further, a mixture of 0.8 g of azobismethylvaleronitrile and 18 g of methyl ethyl ketone was dropped into the flask over 0.5 hours, and then aged for 1 hour.
Next, 0.8 g of azobismethylvaleronitrile was added, followed by aging for 1 hour to obtain 800 g of a 50% by mass polymer solution.

(Example of preparation of yellow pigment dispersion)
-Preparation of yellow pigment dispersion-
28 g of the polymer solution and 26 g of C.I. I. Pigment Yellow 74, 13.6 g of 1 mol / L potassium hydroxide aqueous solution, 20 g of methyl ethyl ketone, and 13.6 g of water were stirred and then kneaded using a roll mill to form a paste.
After the obtained paste was put into 200 g of water and stirred, methyl ethyl ketone and water were distilled off using an evaporator, and a yellow pigment aqueous dispersion having a pigment content of 15% by mass and a solid content of 20% by mass. Got.

(Preparation Example 1 of Yellow Pigment Ink)
-Preparation of yellow pigment ink-
The following composition was stirred by a conventional method for 1 hour to obtain a mixed solution.
[Composition and content]
-1,3-butanediol: 15 parts by mass-1,2-propanediol: 15 parts by mass-Fluorine-based nonionic surfactant (Zonyl FSO-100, manufactured by DuPont): 0.5 parts by mass-Acrylic silicone resin (Nanocrill SBCX-2821, manufactured by Toyo Ink Co., Ltd.): 8.75 parts by mass (3.5 parts by mass in solid content)
・ 1,8-octanediol: 2 parts by mass

Next, after adding the following composition to the mixed solution and stirring for 1 hour with the total being 100 parts by mass, pressure filtration is performed using a polypropylene filter having an average pore size of 1.5 μm to remove coarse particles. A yellow pigment ink of Preparation Example 1 was obtained.
[Composition and content]
-Yellow pigment aqueous dispersion: 40 parts by mass-Water: remaining amount

(Preparation Example 2 of Yellow Pigment Ink)
-Preparation of yellow pigment ink-
Preparation of the yellow pigment ink in Preparation Example 1 of the yellow pigment ink, except that the acrylic silicone resin (Nanoacryl SBCX-2821, manufactured by Toyo Ink Co., Ltd.) was 17.5 parts by mass (7 parts by mass in solid content). In the same manner as in Example 1, a yellow pigment ink of Preparation Example 2 was obtained.

(Cleaning liquid preparation example 1)
The following composition was mixed by a conventional method to prepare the cleaning liquid of Preparation Example 1.
[Composition and content]
-Amide solvent represented by the following structural formula (1) (Ecamide M100, manufactured by Idemitsu Kosan Co., Ltd.): 55 parts by mass
-1,3-butanediol: 5 parts by mass-Glycerin: 10 parts by mass-Fluorine nonionic surfactant (Zonyl FS-300, manufactured by DuPont): 1 part by mass-2-ethyl-1,3-hexanediol : 1 part by mass-2,4,7,9-tetramethyl-4,7-decanediol: 0.1 part by mass-Water: remaining amount (total: 100 parts by mass)

(Cleaning liquid preparation example 2)
The following composition was mixed by a conventional method to prepare the cleaning liquid of Preparation Example 2.
[Composition and content]
-Amide solvent represented by the following structural formula (2) (Ecamide B100, manufactured by Idemitsu Kosan Co., Ltd.): 55 parts by mass
-1,3-butanediol: 5 parts by mass-Glycerin: 10 parts by mass-Fluorine nonionic surfactant (Zonyl FS-300, manufactured by DuPont): 1 part by mass-2-ethyl-1,3-hexanediol : 1 part by mass-2,4,7,9-tetramethyl-4,7-decanediol: 0.1 part by weight
・ Water: remaining amount (total: 100 parts by mass)

(Cleaning liquid preparation example 3)
The following composition was mixed by a conventional method to prepare the cleaning liquid of Preparation Example 3.
[Composition and content]
-Amide solvent represented by the structural formula (1) (Ecamide M100, manufactured by Idemitsu Kosan Co., Ltd.): 30 parts by mass-Amide solvent represented by the structural formula (2) (Ecamide B100, Idemitsu Kosan Co., Ltd.) Manufactured): 30 parts by mass-Glycerin: 10 parts by mass-Fluorine nonionic surfactant (Zonyl FS-300, manufactured by DuPont): 1 part by mass-2-ethyl-1,3-hexanediol: 1 part by mass 2,4,7,9-tetramethyl-4,7-decanediol: 0.1 parts by mass Water: remaining amount (total: 100 parts by mass)

(Cleaning liquid preparation example 4)
The following composition was mixed by a conventional method to prepare the cleaning liquid of Preparation Example 4.
[Composition and content]
3-methoxy-3-methyl-1-butanol: 30 parts by mass Glycerin: 10 parts by mass Fluorine-based nonionic surfactant (Zonyl FS-300, manufactured by DuPont): 1 part by mass 2-ethyl-1 , 3-hexanediol: 1 part by mass ・ 2,4,7,9-tetramethyl-4,7-decanediol: 0.1 part by mass ・ Water: remaining amount (total: 100 parts by mass)

(Cleaning liquid preparation example 5)
The following composition was mixed by a conventional method to prepare the cleaning liquid of Preparation Example 5.
[Composition and content]
-1,3-butanediol: 40 parts by mass-Glycerin: 30 parts by mass-Fluorine nonionic surfactant (Zonyl FS-300, manufactured by DuPont): 1 part by mass-2-ethyl-1,3-hexanediol : 1 part by mass-2,4,7,9-tetramethyl-4,7-decanediol: 0.1 part by mass-Water: remaining amount (total: 100 parts by mass)

(Experimental example 1)
Using an ink jet recording apparatus (IPSiO GXe-5500, manufactured by Ricoh Co., Ltd.) under an environmental condition adjusted to 23 ° C. ± 0.5 ° C. and 50 ± 5% RH, The driving voltage was varied, and the recording medium was set such that the same amount of ink adhered to OK Top Coat manufactured by Oji Paper Co., Ltd. + (Basis weight 104.7 g / m ² ).

Next, the ejection stability was evaluated as follows. The results are shown in Tables 1 to 3.
<Discharge stability>
The ink of Preparation Example 1 was loaded into the inkjet recording apparatus (IPSiO GXe-5500, manufactured by Ricoh Co., Ltd.), and recording was performed for the continuous recording times shown in Tables 1 to 3.
Next, based on the flowchart shown in FIG. 1, the cleaning liquid 300 is applied to the nonwoven fabric 303 as the wiping member by using the cleaning apparatus 300 for the ink discharge head shown in FIG. Then, the wiping member to which the cleaning liquid was applied by the pressing member was pressed against the nozzle surface 301a of the ink discharge head 301 of the ink jet recording apparatus, thereby cleaning the nozzle surface. Butyl rubber is used for the pressing roller 305 as the pressing member in the cleaning apparatus for the ink discharge head shown in FIG. 2, and the nonwoven fabric 303 (trade name: Anticon) is used as the wiping member.
Next, using the inkjet recording device after cleaning the nozzle surface, output a nozzle check pattern and check the number of nozzles with missing nozzles (192 nozzles in total) and discharge stability based on the following criteria: Sex was evaluated.
In the flowchart shown in FIG. 1, X = 1 hour and Y = 3 hours, and the application amount of the cleaning liquid in FIG. 1 is as follows.
“Less amount applied”: 0.1 mL / cm ²
“Applied amount normal”: 0.2 mL / cm ²
“Amount applied”: 0.3 mL / cm ²
[Evaluation criteria]
◎: No missing nozzle ○: No more than 2 nozzles with missing nozzles △: No fewer than 3 nozzles with missing nozzles ×: No fewer than 6 nozzles with missing nozzles

* “Pressure” in the application method of the cleaning liquid means that the application amount of the cleaning liquid is adjusted by increasing or decreasing the pressure applied to the cleaning liquid application nozzle.

(Experimental example 2)
In Experimental Example 1, as shown in Tables 4 and 5, the ejection stability was evaluated in the same manner as in Experimental Example 1 except that the application method of the cleaning liquid was changed. The results are shown in Tables 4 and 5.

* “Number of times of application” in the method of applying the cleaning liquid means adjusting the application amount of the cleaning liquid by increasing or decreasing the number of times of applying the cleaning liquid.

* “Number of applied nozzles” in the application method of the cleaning liquid means that the application amount of the cleaning liquid is adjusted by increasing or decreasing the number of nozzles applied by the plurality of cleaning liquid applying nozzles.

(Experimental example 3)
In Experimental Example 1, the ink jet recording apparatus after recording with the continuous recording time shown in Tables 6 to 8 using the ink of Preparation Example 2 was applied to the nozzle surface using the cleaning liquid application amount and application method shown in Tables 6 to 8. The ejection stability was evaluated in the same manner as in Experimental Example 1 except that the cleaning was performed. The results are shown in Tables 6-8.
In the flowchart shown in FIG. 1, X = 0.5 hour, Y = 1 hour, and the application amount of the cleaning liquid in FIG. 1 is as follows.
“Less amount applied”: 0.08 mL / cm ²
“Applied amount normal”: 0.18 mL / cm ²
“Amount applied”: 0.25 mL / cm ²

  From the results of Tables 1 to 8, it was found that the discharge stability is improved by controlling the application amount of the cleaning liquid and the application method of the cleaning liquid to appropriate conditions according to the continuous recording time.

Aspects of the present invention are as follows, for example.
<1> A method of cleaning an ink discharge head for cleaning the nozzle surface of the ink discharge head,
Applying a cleaning liquid to the wiping member on the pressing member;
Wiping the nozzle surface with a wiping member to which a cleaning liquid is applied, and
A method for cleaning an ink discharge head, wherein the application amount of the cleaning liquid is controlled by a recording time.
<2> The method for cleaning an ink ejection head according to <1>, wherein the application amount of the cleaning liquid is selected from a plurality of set amounts.
<3> The method for cleaning an ink ejection head according to any one of <1> to <2>, wherein an application amount of the cleaning liquid is controlled by pressure.
<4> The ink discharge head cleaning method according to any one of <1> to <2>, wherein the cleaning liquid is applied from a plurality of nozzles, and an application amount of the cleaning liquid is controlled by a number of the nozzles.
<5> The method for cleaning an ink ejection head according to any one of <1> to <2>, wherein the application amount of the cleaning liquid is controlled by the number of application times of the cleaning liquid.
<6> The method for cleaning an ink ejection head according to any one of <1> to <5>, wherein the cleaning liquid contains at least one of compounds represented by the following structural formulas (1) and (2). is there.
<7> The ink discharge head cleaning method according to any one of <1> to <6>, wherein the cleaning liquid contains 3-methoxy-3-methyl-1-butanol.
<8> An ink discharge head cleaning device for cleaning the nozzle surface of the ink discharge head,
Means for applying a cleaning liquid to the wiping member on the pressing member;
A means for wiping the nozzle surface with a wiping member to which a cleaning liquid is applied, and
The cleaning apparatus for an ink discharge head, wherein the application amount of the cleaning liquid is controlled by a recording time.
<9> The cleaning apparatus for an ink discharge head according to <8>, wherein the application amount of the cleaning liquid is selected from a plurality of set amounts.
<10> The ink ejection head cleaning device according to any one of <8> to <9>, wherein an application amount of the cleaning liquid is controlled by pressure.
<11> The ink ejection head cleaning device according to any one of <8> to <9>, wherein the cleaning liquid is applied from a plurality of nozzles, and the application of the cleaning liquid is controlled by the number of the nozzles.
<12> The ink discharge head cleaning device according to any one of <8> to <9>, wherein the application amount of the cleaning liquid is controlled by the number of times the cleaning liquid is applied.
<13> The cleaning apparatus for an ink discharge head according to any one of <8> to <12>, wherein the cleaning liquid contains at least one of compounds represented by the following structural formulas (1) and (2). is there.
<14> The ink discharge head cleaning device according to any one of <8> to <13>, wherein the cleaning liquid contains 3-methoxy-3-methyl-1-butanol.
<15> a discharge step of discharging ink from the nozzle surface on the ink discharge side of the nozzle plate of the ink discharge head;
A cleaning step of cleaning the nozzle surface by the method of cleaning an ink discharge head according to any one of <1> to <7>;
The recording method is characterized by including:
<16> an ink discharge head for discharging ink;
The ink discharge head cleaning device according to any one of <8> to <14>, wherein the nozzle surface on the ink discharge side of the nozzle plate of the ink discharge head is cleaned.
It is a recording device characterized by having.

  The ink discharge head cleaning method according to any one of <1> to <7>, the ink discharge head cleaning device according to any one of <8> to <14>, and the recording according to <15>. The method and the recording apparatus according to <16> can solve the above-described problems and achieve the object of the present invention.

DESCRIPTION OF SYMBOLS 300 Ink discharge head washing | cleaning apparatus 301 Ink discharge head 301a Nozzle surface 302 Cleaning liquid provision means 303 Wiping member (nonwoven fabric)
304 Winding roller 305 Pressing member (Pressing roller)

JP 2014-172245 A Japanese Patent No. 5149231

Claims (16)

An ink discharge head cleaning method for cleaning a nozzle surface of an ink discharge head,
Applying a cleaning liquid to the wiping member on the pressing member;
Wiping the nozzle surface with a wiping member to which a cleaning liquid is applied, and
An ink discharge head cleaning method, wherein the amount of the cleaning liquid applied is controlled by a recording time.   The method for cleaning an ink discharge head according to claim 1, wherein the application amount of the cleaning liquid is selected from a plurality of set amounts.   The method for cleaning an ink discharge head according to claim 1, wherein the application amount of the cleaning liquid is controlled by pressure.   The method of cleaning an ink ejection head according to claim 1, wherein the cleaning liquid is applied from a plurality of nozzles, and the amount of the cleaning liquid applied is controlled by the number of the nozzles.   The method for cleaning an ink discharge head according to claim 1, wherein the amount of the cleaning liquid applied is controlled by the number of times the cleaning liquid is applied. The method for cleaning an ink ejection head according to claim 1, wherein the cleaning liquid contains at least one of compounds represented by the following structural formulas (1) and (2).
  The method for cleaning an ink ejection head according to claim 1, wherein the cleaning liquid contains 3-methoxy-3-methyl-1-butanol. An ink discharge head cleaning device for cleaning the nozzle surface of an ink discharge head,
Means for applying a cleaning liquid to the wiping member on the pressing member;
A means for wiping the nozzle surface with a wiping member to which a cleaning liquid is applied, and
A cleaning device for an ink discharge head, wherein the application amount of the cleaning liquid is controlled by a recording time.   The ink discharge head cleaning device according to claim 8, wherein the application amount of the cleaning liquid is selected from a plurality of set amounts.   The ink ejection head cleaning device according to claim 8, wherein the application amount of the cleaning liquid is controlled by pressure.   The ink discharge head cleaning device according to claim 8, wherein the cleaning liquid is applied from a plurality of nozzles, and the application of the cleaning liquid is controlled by the number of the nozzles.   The ink ejection head cleaning device according to claim 8, wherein the amount of the cleaning liquid applied is controlled by the number of times the cleaning liquid is applied. The ink discharge head cleaning device according to claim 8, wherein the cleaning liquid contains at least one of compounds represented by the following structural formulas (1) and (2).
  The ink discharge head cleaning device according to claim 8, wherein the cleaning liquid contains 3-methoxy-3-methyl-1-butanol. A discharge step of discharging ink from the nozzle surface on the ink discharge side of the nozzle plate of the ink discharge head;
A cleaning step of cleaning the nozzle surface by the method of cleaning an ink discharge head according to any one of claims 1 to 7;
A recording method comprising: An ink discharge head for discharging ink;
The ink discharge head cleaning device according to any one of claims 8 to 14, wherein a nozzle surface of the ink discharge side of the nozzle plate of the ink discharge head is cleaned.
A recording apparatus comprising: