JPH08197731A - Ink jet device and production thereof - Google Patents

Abstract

PURPOSE: To produce an ink jet device not closing ink channels or nozzle parts and capable of inexpensively performing ink affinity imparting treatment. CONSTITUTION: Liquid chambers 15 are formed by closing the grooves formed to an actuator plate 11 by a cover plate 20. Manifolds 17a are allowed to communicate with the respective liquid chambers 15 and the nozzles 12a formed to a nozzle plate 12 are allowed to communicate with the liquid chambers 15. A pigment layer 16 is formed to the inner walls of the manifolds 17a, the liquid chambers 15 and the nozzles 12a. Since ink affinity is imparted by the pigment layer 16, the involution of air bubbles is eliminated and ink droplets are made uniform in jet direction and ejected at a stable flight speed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet device for recording characters and images with ink and a method for producing the ink jet device. More specifically, the present invention relates to an ink flow path provided in the ink jet device. The present invention relates to an inkjet device that has been inked, and a manufacturing method thereof.

[0002]

2. Description of the Related Art Conventionally, in an ink jet device, various proposals have been made for improving wettability of a liquid contact surface with ink in an ink flow path extending to an ink storage section, an ink supply path and a head nozzle tip (making the ink hydrophilic). Has been done.

For example, US Pat. No. 4,725,862,
As disclosed in Japanese Patent Application Laid-Open No. 60-24957, on a surface of a resin-made head constituent member that comes into contact with ink,
There is one that does not leave bubbles in the pressure chamber at the time of ink filling and facilitates the removal of the generated bubbles by imparting the same properties as glass by chemical treatment, ultraviolet light, plasma, corona discharge, flame treatment and the like. Also, JP-A-63-2
As disclosed in Japanese Patent No. 2660, there is a method of forming an ink-philic film by coating a silicon-based film on the nozzle end surface by an ion plating method. Further, as disclosed in Japanese Patent Publication No. 2-54784, heating is performed in a state where an aqueous dye solution and a liquid contact surface of an inkjet device are in contact with each other, and the dye is preliminarily attached or adsorbed to the liquid contact surface, Some improve the wettability of the liquid contact surface.

[0004]

However, in the ink-affinity treatment of the liquid contact surface in the conventional ink jet apparatus, a chemical solution treatment, ultraviolet rays, or the like to give properties equivalent to those of glass, or a silicon film formed by an ion plating method is used. In the case of forming, there is a problem that it is difficult to process the inner wall surface of a thin and long pipe or a material having a complicated shape, and the apparatus is expensive.

Further, in the case of a method in which the dye aqueous solution and the liquid contact surface of the ink jet device are in contact with each other and heated to adhere or adsorb the dye, when the ink used in the ink jet device is the same dye ink Although there is no problem, pigment inks which are excellent in water resistance, weather resistance, and color development in the required characteristics of printing quality for today's ink jet devices are drawing attention. When such a pigment ink is used, the dye ink used for the treatment and the pigment ink used are mixed when the initial pigment ink is introduced, and the reaction and discoloration cause precipitation in the channel and deterioration of the initial print quality. Further, if the pigment ink is introduced after washing the inside of the head that has been treated with the dye ink and drying the inside of the head, such a problem does not occur, but a washing step and a drying step are required. Therefore, it takes time and productivity is low.

The present invention has been made in order to solve the above-mentioned problems, and is an ink jet apparatus having a high print quality, which does not entrap air bubbles and ejects ink droplets in a uniform ejection direction and in a stable manner. It is also an object of the present invention to provide a method for manufacturing an inkjet device, which is very effective when a pigment ink is used and can be inexpensively treated as an ink-philic ink.

[0007]

In order to achieve this object, the ink jet device of the present invention records characters and images with ink, and further, the above pigment is applied to the liquid contact surface of the ink flow path. It has a pigment layer attached or adsorbed.

The ink used for the recording may be pigment ink.

In addition, the method of manufacturing an ink jet device of the present invention is a method of making the ink flow path of the ink jet device for recording characters and images with ink to be ink-philic, and a solution containing a pigment is flowed through the ink flow path. And the pigment is previously attached or adsorbed to the liquid contact surface of the ink flow path.

The solution containing the pigment may be a pigment dispersion solution in which the pigment is dispersed in a solvent.

The pigment is added to the pigment dispersion solution in an amount of 2
It may be contained in a proportion of ˜15% by weight.

A dispersant may be used to disperse the pigment.

The time for which the solution containing the pigment is brought into contact with the liquid contact surface of the ink flow path may be 5 minutes or more.

The solution containing the pigment may be heated while being in contact with the liquid contact surface of the ink flow path.

The ink used for recording may be an ink jet device which is a pigment ink.

[0016]

In the ink jet device according to the third aspect of the present invention having the above-mentioned structure, the pigment layer makes the liquid contact surface of the ink flow path ink-philic and discharges the bubbles trapped in the ink flow path. Is improved, and ink droplets are ejected with a uniform ejection direction and a stable flight speed.

In the ink jet apparatus according to the second aspect, characters and images are recorded by the pigment ink which is excellent in water resistance, weather resistance and color development.

In the method for manufacturing an ink jet device according to the third aspect of the present invention having the above structure, the solution containing the pigment is brought into contact with the liquid contact surface of the ink flow path,
The pigment adheres to or is adsorbed on the liquid contact surface of the ink flow path to make the liquid contact surface ink-philic, which improves the dischargeability of entrained bubbles, and makes the ink jetting direction uniform and having a stable flight speed. An inkjet device is created in which drops are ejected.

In the method of manufacturing an ink jet device according to the fourth aspect, since the ink-philic treatment is performed using the pigment dispersion solution in which the pigment is dispersed in the solvent, the pigment is evenly distributed in the ink flow path. A uniform process is performed over the entire ink flow path.

In the method for manufacturing an ink jet device according to a fifth aspect, the pigment is contained in the pigment dispersion solution in a proportion of 2 to 15% by weight. When the solution containing this pigment is used, the processing time can be shortened, and the ink-philic treatment with sufficient durability is performed.

In the method for manufacturing an ink jet device according to a sixth aspect, a pigment dispersion solution in which a pigment is dispersed using a dispersant is used. Therefore, in the process of adhering or adsorbing the pigment to the liquid contact surface of the ink flow path, a device such as a stirring device for keeping the pigment in the solution in a dispersed state is not necessary, and further, the dispersed state of the pigment in the solution is No need for control, and uniform ink-philicity treatment is performed over the entire ink flow path.

In the method for manufacturing an ink jet device according to the seventh aspect, the solution containing the pigment is brought into contact with the liquid contact surface of the ink flow path for 5 minutes or more. Therefore, the pigment is surely adhered to or adsorbed on the liquid contact surface, and a highly reliable ink-philic treatment is performed.

In the method for manufacturing an ink jet device according to an eighth aspect, the solution containing the pigment is heated while being in contact with the liquid contact surface of the ink flow path. Therefore, the pigment is more likely to be attached or adsorbed on the liquid contact surface.

In the method for manufacturing an ink jet device according to a ninth aspect, the ink jet device is produced in which the ink used for recording is a pigment ink excellent in water resistance, weather resistance and color development.

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An ink jet device according to an embodiment of the present invention is shown in FIGS. The ink jet device of this embodiment records characters and images with pigment ink.

The ink in the ink storage section 19 is filled in the liquid chamber 15 and the nozzle 12a through the ink supply passage 18 and the manifold 17a of the head 1. Head 1
Is composed of an actuator plate 11 made of piezoelectric ceramics (lead zirconate titanate), a cover plate 20, and a manifold member 17. The actuator plate 11 is polarized in the direction of arrow A,
A plurality of grooves are formed. By closing the groove with the cover plate 20 made of ceramics,
The liquid chamber 15 is formed. The cover plate 20 is formed with an opening communicating with all the liquid chambers 15, and a manifold 17a is arranged so as to cover the opening. Further, each liquid chamber 15 is communicated with a nozzle 12a formed in a nozzle plate 12 made of polyimide. An electrode 14 is formed on the upper half of the side surface of the groove of the actuator plate 11. On the inner wall of the liquid chamber 15, a protective film (not shown) for protecting the electrode 14 from the ink is formed of epoxy resin. The pigment layer 16 is formed on the inner walls of the manifold 17a and the liquid chamber 15 on the protective film.

Next, the operation of the head 1 having such a structure will be described. When the electrode 14a and the electrode 14c are grounded and a pulse waveform voltage is applied to the electrode 14b, the piezoelectric thickness slips and deforms so that the walls 11a and 11b of the actuator plate 11 are separated from each other, and the ink is supplied into the liquid chamber 15b. To be done. After a predetermined time, when the voltage application is stopped, the wall 11
The inks 13a and 11b return to the original state, pressure is applied to the ink in the liquid chamber 15b, and the ink droplet 13 is ejected from the nozzle 12a.

Next, a method for forming the pigment layer 16 on the inner walls of the manifold 17a, the liquid chamber 15 and the nozzle 12a will be described. A solution containing a pigment in a dispersed state (hereinafter referred to as a pigment dispersion solution) is filled inside the head 1, that is, the manifold 17a, the liquid chamber 15, and the nozzle 12a, and the pigment is attached or adsorbed to the inner wall of the head 1. Then, the pigment layer 16 is formed. The pigment dispersion solution may be water-soluble or oil-based. Further, any pigment can be used as long as it does not chemically react with other components added to the pigment dispersion solution (for example, a viscosity adjusting agent described later) or generate a precipitate.

The pigment used in the present invention may be an organic pigment or an inorganic pigment. For example, examples of the inorganic pigment include titanium oxide and iron oxide, and carbon black produced by a commonly known method such as a contact method, a furnace method, and a thermal method, and examples of the organic pigment include an azo lake pigment and an insoluble azo pigment. Polycyclic pigments such as azo pigments such as condensed azo pigments and chelate azo pigments, phthalocyanine pigments, perylene and perinone pigments, anthraquinone pigments, quinacridone pigments, dioxazine pigments, thioindico pigments, isoindolinone pigments, quinophthalone pigments and basic dye types Dye lakes such as lakes and acid dye type lakes, nitro pigments, nitroso pigments, aniline black, etc. can be mentioned.

The above-mentioned examples of pigments are particularly preferable for the solution containing the pigment of the present invention, and the pigment used in the present invention is not limited to these pigments.

Further, these pigments are used in a proportion of 1 to 25% by weight with respect to the pigment dispersion solution of this embodiment. This is because if the content is less than 1% by weight, the pigment does not sufficiently spread on the liquid contact surface and an insufficient layer is formed.
On the other hand, if the content exceeds 25%, the pigment excessively adheres and deposits on the liquid surface, and as a result, the cross-sectional shape of the ink flow path of the head 1 and the nozzle 12a changes, which adversely affects ink ejection. Further, from the viewpoint of the processing time required for forming the pigment layer 16 and the durability of the pigment layer 16, it is desirable that the pigment layer 16 be used in a proportion of 2 to 15% by weight. As a result, the pigment layer 1 formed by a short-time treatment and having a sufficient thickness
6 can be formed.

Further, in this embodiment, a pigment dispersion solution in which a pigment is dispersed in a solvent using a dispersant is used. Suitable dispersants for dispersing the pigment used in the present invention include polymer dispersants, phosphoric acid ester-based surfactants, surfactants containing fluorine or boron, polyoxyethylene alkyl ether or polyoxyethylene alkenyl ether-based surfactants. Examples thereof include surfactants.

Examples of the polymer dispersant include proteins such as gelatin, albumin and casein, natural rubbers such as arabic gum and tragacanth, glucosides such as savonine, natural polymers such as lignin sulfonate and shellac, and polyacryl. Acid salt, polymethacrylic acid salt, salt of styrene-acrylic acid copolymer, salt of vinylnaphthalene-acrylic acid copolymer, salt of styrene-maleic acid copolymer, salt of maleic acid-maleic anhydride copolymer , Vinylnaphthalene-maleic acid copolymer salt, sodium salt of β-naphthalenesulfonic acid formalin condensate, anionic polymer such as phosphate, and nonionic polymer such as polyvinyl alcohol and polyvinylpyrrolidone.

Examples of the phosphate ester type surfactant include sodium polyoxyethylene lauryl ether phosphate, sodium polyoxyethylene cetyl ether phosphate, sodium polyoxyethylene oleyl ether phosphate and the like.

As the surfactant containing fluorine or boron, a perfluoroalkylsulfonic acid compound,
Examples thereof include polyoxyethylene glycerol borate-laurate, polyoxyethylene glycerol borate-palmitate, polyoxyethylene glycerol borate-stearate, polyoxyethylene glycerol borate-oleate, and polyoxyethylene glycerol borate-isostearate.

The above examples of the dispersant are particularly preferable for the solution containing the pigment of the present invention, and the dispersant used in the present invention is not limited to these dispersants.

These dispersants are preferably used in a proportion of 0.001 to 10% by weight, more preferably 0.01 to 5% by weight, based on the solution of the present invention.

The solvent suitable for use in the pigment solution is a mixed solvent of ion-exchanged water having Ca ions and Mg ions of 5 ppm or less and a water-soluble organic solvent, and alkyl alcohols having 1 to 4 carbon atoms and ketones. Or, ketone alcohols, ethers, polyalkylene glycols, alkylene glycols having an alkylene group containing 2 to 6 carbons, glycerin, lower alkyl ether of polyhydric alcohol, N-methyl-2-pyrrolidone, 1-3- Dimethyl
2-Imidazolidinone, triethanolamine, ethylene glycol and the like are used, but not limited thereto.

The basic constitution used in the pigment dispersion solution of the present embodiment is as described above. Conventionally known viscosity adjusting agents, surface tension adjusting agents, resistivity adjusting agents, pH adjusting agents (sodium hydroxide, hydroxide Lithium, potassium hydroxide, etc.), fungicides, penetrants (methanol, ethanol, propanol, etc.), chelating agents and the like can be added as necessary.

Further, as a method of dispersing the pigment, it is desirable to use a dispersing machine such as a ball mill, a sand mill, an attritor, a roll mill, an agitator mill, a Henschel mixer, a colloid mill, an ultrasonic homogenizer, a pearl mill, a jet mill, an ong mill. It is not limited to these.

The present invention will be described below with reference to specific examples and comparative examples, but the examples do not limit the present invention.

The pigment layer 16 is provided in the liquid chamber 15 of the head 1 described above.
The conditions for forming the are changed, and the formed pigment layer 16 is evaluated. After washing and drying the inside of the head 1 in which the protective film made of epoxy resin is formed on the inner wall of the liquid chamber 15, the head 1 is filled with the pigment dispersion solution using a suction pump,
After that, the treatment time was changed from one that was contacted for a moment at room temperature and each temperature condition to 8 hours to obtain a pigment layer 16 under various manufacturing conditions. It is difficult to measure the contact angle with the ink in the liquid chamber 15 and the nozzle 12a because the size of the liquid chamber 15 and the nozzle 12a is extremely small.
Therefore, the pigment layer 16 was formed on the epoxy plate and the polyimide plate under the same treatment conditions as above, and the contact angle with the ink was measured.

Evaluations 1 to 4 were carried out on the head 1 and the epoxy and polyimide single plates to confirm the effect of the pigment layer 16 on the ink-philic treatment.

Evaluation 1 Ion-exchanged water was dropped on a single plate of epoxy and polyimide on which a pigment layer 16 was formed by the following pigment dispersion solution, and the contact angle was measured. The results are shown in FIGS. 3 and 4. From these results, it can be seen that the contact angle with ion-exchanged water becomes smaller as the treatment time becomes longer and the treatment temperature becomes higher, so that the ink becomes an ink-philic ink. Also, FIG.
As shown in, the change in the contact angle is large when the processing time is less than 5 minutes, and the change in the contact angle is small when the processing time is 5 minutes or more. Therefore, it is understood that the processing time is preferably about 5 minutes or more and the processing temperature is preferably high.

Pigment dispersion solution Pigment: Carbon black 4% Dispersant: Fluorine-based surfactant 2% Glycerin 4% Ion-exchanged water 90%.

Evaluation 2 The ink in the ink storage portion 19 was sucked by a suction pump (not shown) using the example head in which the pigment layer 16 was formed using the pigment dispersion solution and the heads in Comparative Examples 1 and 2 described later. No.) is driven to suck from the nozzle side, and the manifold 1
7a, the liquid chamber 15, and the initial filling property for filling the nozzle 12a were observed. As an observation item, the number of nozzles 12a that could not be filled after the ink was sucked was counted and compared. Further, bubbles were intentionally generated inside the liquid chamber 15 of the head 1, and about 0.01 cc was sucked at once by the suction pump, and the number of suction times required to remove the bubbles was compared.

The inks used for the evaluation of the initial filling property and the bubble discharging property are described below.

Ink Pigment: Carbon black 4% Dispersant: Fluorosurfactant 2% Ethanol 5% Glycerin 20% Propylene glycol 20% Ion-exchanged water 49%.

The head of Comparative Example 1 was prepared by cleaning the inside of the head 1 with ion-exchanged water without providing the pigment layer 16, and the head of Comparative Example 2 was prepared by cleaning the inside of the head 1 with ion-exchanged water. After washing with, the dye solution and the liquid contact surface are heated in the same manner as in the prior art, and the dye solution used for the treatment is a general dye ink shown below.

Ink (Dye Treatment Ink Used in Comparative Example 2) Dye: C.I. I. Direct Black 154 2% Ethanol 5% Glycerin 4% Ion-exchanged water 89%.

As shown in FIG. 5, in the head of the embodiment,
The product manufactured under the condition that the treatment time was 3 minutes had a small number of nozzles that could not be filled in the initial filling, and the suction pump was driven 20 times during bubble discharge, but could not be removed, and the treatment time was other than 3 minutes. Products manufactured under the conditions can be filled into all nozzles, and the suction pump can be driven 1 times.
Or twice. In the head of Comparative Example 1, there were a small number of nozzles that could not be filled in the initial filling, and the suction pump was driven 20 times during bubble discharge, but could not be removed.

From these results, it is possible to satisfactorily carry out the initial filling of the head on which the pigment layer 16 has been formed and to discharge the bubbles satisfactorily under the condition that the processing time is about 5 minutes or more.

Further, in the head of Comparative Example 2, the test result after washing away the dye solution in the ink flow passage was almost the same as that of the head of the embodiment, but the dye in the ink flow passage was In the head tested without washing away the solution, the introduced pigment ink reacts with the dye solution and accumulates in the ink flow path, most of the nozzles cannot be filled with ink, and a suction pump for discharging bubbles is installed. It was driven 20 times but could not be removed.

Evaluation 3 Next, ink ejection evaluation of the head of the example and the heads of the comparative examples 1 and 2 was performed. The driving condition is a voltage of 30.
V, the frequency was 5 KHz, and the stable injection time was measured. The result is shown in FIG.

As shown in FIG. 6, in the head of Comparative Example 1, the stable jetting time was extremely short as compared with the other heads. In the head of Comparative Example 2, the test result after washing away the dye solution in the ink flow path was as follows.
Although it was almost the same as the head of the example, in the head which was tested without washing away the dye solution in the ink flow path, as described in Evaluation 2, the introduced pigment ink and the dye solution react with each other, and the ink flow path Even with the nozzles that had accumulated inside and could be filled with ink, there was little time for stable ejection.

From this result, the head on which the pigment layer is formed can eject stably for a long time.
Particularly, a head manufactured under the condition that the processing time is about 5 minutes or more has a long stable jetting time.

Evaluation 4 From the results of Evaluations 1 to 3, it was confirmed that forming the pigment layer 16 on the inner wall of the head 1 improved the ink affinity. In order to confirm the persistence of this effect, after measuring the contact angle of ion-exchanged water on the single plate of polyimide in Evaluation 1, the single plate was left in a constant temperature bath at 60 ° C and the contact angle was measured every 2 days. did. The measurement result is shown in FIG.

From the result of FIG. 7, in the plate of the example,
It was confirmed that the initial contact angle was maintained almost unchanged and the durability was excellent. Particularly, the plate under the condition that the treatment time is 5 minutes or more has excellent durability. Comparative Example 1
The plate is not wetted with ink because it is not treated with ink. It was found that in Comparative Example 2, the contact angle was slightly changed as compared with the plates of Examples produced under the same conditions, and the durability was difficult.

From the results of Evaluations 1 to 4 above, when the pigment layer was previously adhered or adsorbed on the surface in contact with the ink, it became an ink-philic ink, which caused a marked difference from the untreated one, and the initial filling property, Both the bubble discharge property and continuous discharge time are improved, and the effect is excellent in sustainability.

In addition, pigment inks which are excellent in water resistance, weather resistance and color developability are attracting attention in the required characteristics of printing by ink jet devices today. When such pigment inks are used, they are used together with a pigment solution used for treatment. The pigment ink does not mix when the initial pigment ink is introduced and cause precipitation in the channel or deterioration of the initial print quality due to discoloration, reaction, or the like. Further, since the unit price is lower than that of dye, the cost of the ink-affinity conversion treatment can be reduced.

The present invention is not limited to the above-described embodiments, and various modifications may be made without departing from the spirit of the present invention. For example, in this embodiment, the pigment layer 16 was formed after the head 1 was assembled, but the head may be assembled after the pigment layer is formed for each individual component before the assembly. Further, it is not necessary to form the pigment layer on all the components, and for example, another hydrophilic layer may be provided in the nozzle, for example, another hydrophilic layer may be provided in the nozzle.

In this embodiment, the pigment layer is formed on the piezoelectric thickness slip deformation head.
Kaiser type disclosed in Japanese Patent Publication No. 138 and Japanese Patent Publication No. 61
Similar effects can be obtained by forming a pigment layer on a thermal jet type head disclosed in Japanese Patent Publication No. 59914.

[0063]

As is apparent from the above description, according to the ink jet device and the method for manufacturing the same of the present invention, the solution containing the pigment is brought into contact with the liquid contact surface of the ink flow path. The pigment adheres to or is adsorbed on the liquid contact surface to make the liquid contact surface ink-philic. For this reason,
The inclusion of bubbles is eliminated, and ink droplets are ejected with a uniform ejection direction and a stable flight speed. In addition, the initial filling of ink into the ink flow path can be favorably performed, and bubbles generated in the ink flow path can be easily discharged. Therefore, long-term reliability of the inkjet device can be ensured.

Further, pigment inks which are excellent in water resistance, weather resistance and color developability are attracting attention in the required printing characteristics of today's ink jet devices. When such pigment inks are used, they are used together with a pigment solution used for treatment. The pigment ink does not mix when the initial pigment ink is introduced and cause precipitation in the channel or deterioration of the initial print quality due to discoloration, reaction, or the like.

Further, since the unit price of the dye is lower than that of the dye, the cost of the ink-affinity conversion treatment can be reduced.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an inkjet device according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing an inkjet device according to an embodiment of the present invention.

FIG. 3 is an explanatory diagram showing the relationship between the ink affinity treatment time and the contact angle in the embodiment.

FIG. 4 is an explanatory diagram showing a relationship between an ink-philic treatment temperature and a contact angle in the embodiment.

FIG. 5 is an explanatory diagram regarding initial filling and bubble discharge of the ink-affinity imparting process of the embodiment and the ink-affinity imparting process of the comparative example.

FIG. 6 is an explanatory diagram showing jetting stabilization times of the ink-affinity imparting process of the embodiment and the ink-affinity imparting process of the comparative example.

FIG. 7 is an explanatory diagram showing durability of ink affinity between the ink-affinity imparting process of the example and the comparative example.

[Explanation of symbols]

 1 Head 11 Actuator Plate 12 Nozzle Plate 12a Nozzle 13 Ink Droplet 15 Liquid Chamber 16 Pigment Layer 17 Manifold Member 17a Manifold

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display location B41J 2/16 2/135 B41J 3/04 103 H 103 N

Claims (9)

[Claims] 1. An ink jet device for recording characters and images with ink, comprising a pigment layer having a pigment adhered or adsorbed to a liquid contact surface of an ink flow path. 2. The ink jet apparatus according to claim 1, wherein the ink used for recording the characters and images is a pigment ink. 3. A method for manufacturing an ink jet device in which an ink flow channel of an ink jet device for recording characters and images with ink is subjected to ink-affinity treatment, a solution containing a pigment is brought into contact with a liquid contact surface of the ink flow channel. A method for manufacturing an inkjet device, wherein the pigment is previously attached or adsorbed to the liquid contact surface of the ink flow path. 4. The method of manufacturing an inkjet device according to claim 3, wherein the solution containing the pigment is a pigment dispersion solution in which the pigment is dispersed in a solvent. 5. The pigment is contained in the pigment dispersion solution in an amount of 2 to 2.
The method for manufacturing an inkjet device according to claim 4, wherein the content is 15% by weight. 6. The method for manufacturing an inkjet device according to claim 4, wherein a dispersant is used to disperse the pigment. 7. The method for manufacturing an inkjet device according to claim 3, wherein the time period for which the solution containing the pigment is brought into contact with the liquid contact surface of the ink flow path is 5 minutes or more. 8. The method for manufacturing an inkjet device according to claim 3, wherein the solution containing the pigment is heated while being in contact with the liquid contact surface of the ink flow path. 9. The method for manufacturing an ink jet device according to claim 3, wherein the ink used for recording the characters and images is an ink jet device.