JP3524344B2 - Method of manufacturing inkjet head, inkjet head and inkjet printing apparatus - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inkjet head used in an inkjet printing system and a method for manufacturing the same.

[0002]

2. Description of the Related Art Conventionally, it has been known that a certain kind of aromatic onium salt initiates cationic polymerization of an epoxy resin by light irradiation (for example, Japanese Patent Publication Nos. 52-14277 and 52-14278). ). Further, it is known that these aromatic onium salts act as an initiator of thermal polymerization when used in combination with a substance having a reducing property, for example, a copper compound (for example, USP-417355).
1, USP-4216288).

In addition, the applicant of the present invention, the above-mentioned epoxy resin,
It has been proposed to use an epoxy resin composition composed of an aromatic onium salt and a copper compound as a material for forming an ink flow path of an inkjet head (Japanese Patent Laid-Open No. 6-28614).
No. 9).

[0004]

However, although the above-mentioned composition has relatively excellent curability and adhesion to the substrate, it has a problem in that process control becomes complicated due to its thermal stability. there were.

The present invention has been made in view of the above problems, and it is an object of the present invention to provide a simple composition while maintaining excellent curability and adhesion to a substrate of a composition made of the epoxy resin or the like. An object of the present invention is to provide an inkjet head manufacturing method and an inkjet head capable of manufacturing an inkjet head in a process.

[0006]

In order to achieve the above object, the present invention is a method for manufacturing an ink jet head, in which copper is formed on the surface of a substrate on which an element for generating a pressure for ejecting ink is formed. Compound and silane coupling agent
Attaching a solution containing the copper compound and the silane
A step of forming a resin layer forming an ink flow path forming member on the substrate to which the solution containing a pulling agent is attached, wherein the resin composition forming the resin layer is at least a cationically polymerizable epoxy resin. And an aromatic onium salt.

According to another aspect of the method for manufacturing an ink jet head, an ink flow path pattern is made of a soluble resin on a part of a substrate on which an element for generating a pressure for ejecting ink is formed. A step of forming, a step of attaching a solution containing a copper compound and a silane coupling agent to the surface of the substrate, the copper compound and a silane coupling agent
A step of forming a resin layer forming an ink flow path forming member on the substrate to which the solution containing is attached, a step of curing the ink flow path forming member by light irradiation, and a step of forming the element of the ink flow path forming member. The resin composition forming the resin layer includes a step of forming an ink discharge port at a corresponding position and a step of eluting an ink flow path pattern formed of the soluble resin, and the resin composition forming the resin layer is at least cationically polymerized. It is characterized in that it contains possible epoxy resins and aromatic onium salts.

[0008]

[0009]

In the above structure, the aromatic onium salt and the copper compound react rapidly at a temperature of about 150 ° C. or higher to accelerate the cationic polymerization reaction of the epoxy resin, and have excellent cured physical properties (adhesion strength to substrate / ink resistance). ) Can be obtained. Here, although a similar effect can be obtained by previously adding a copper compound internally to a resin composition containing an epoxy resin and an onium salt, a dark reaction between the epoxy resin / onium salt and the copper compound gradually proceeds, There has been a problem that the viscosity of the resin composition changes and strict process control is required.

Therefore, according to the present invention, as in the above constitution, the copper compound is not internally added to the resin composition containing the epoxy resin and the onium salt (therefore, no dark reaction occurs and the composition does not change with time). ), By depositing a copper compound in advance on the surface of the substrate on which the resin layer is formed, a nozzle material having excellent cured physical properties is obtained by heat treatment in a subsequent step. In addition, the silane coupling agent above
By adhering to the substrate surface with the copper compound,
High adhesion between the oil layer and the substrate surface can be obtained.

[0012]

DETAILED DESCRIPTION OF THE INVENTION Embodiments of the present invention will be described in detail below with reference to the drawings.

FIGS. 1 to 8 are schematic views showing the construction of an ink jet head according to an embodiment of the present invention and the manufacturing procedure thereof. Hereinafter, the steps will be described in order with reference to these drawings.

As the head of this embodiment, as shown in FIG. 1, a substrate 1 made of glass, ceramic, plastic, metal or the like is prepared. On this substrate 1, a plurality of discharge pressure generating elements 2 such as electrothermal converting elements or piezoelectric elements are arranged at desired positions. Further, the substrate 1 is provided with an ink supply port 3, which allows ink to be supplied from behind the substrate 1 (in the figure).

Next, FIG. 2 showing a cross section taken along the line AA 'of FIG.
As shown in FIG. 5, each ink flow path pattern 4 is formed as a soluble resin layer on the substrate 1 so as to cover each ejection generating element.

The most common means for forming the resin layer is to laminate a photosensitive material in the form of a dry film and pattern it by ordinary photolithography. The ink flow path pattern 4 needs to be formed of a soluble resin because it is removed in a later step, and in the case of a positive type resist or a negative type resist, a solubility change type resin can be used.

As shown in FIG. 3, the copper compound 5 is deposited on the soluble resin layer in which the ink flow path is patterned in this way.

Specific methods are as follows: a copper compound is dissolved in an appropriate solvent and attached on the substrate by spin coating, a substrate is soaked in a solvent in which the copper compound is dissolved, or a high adhesion is usually obtained. Examples include a method of simultaneously depositing a copper compound during the silane coupling treatment.

The most effective copper compound here is copper triflate (copper trifluoromethanesulfonate). When this copper triflate acts as a reduction catalyst for an aromatic onium salt, trifluoromethanesulfonic acid is produced and acts as a catalyst for cationic polymerization,
This is because it has advantages such as high solubility in an epoxy resin as compared with other copper compounds.

After depositing the copper compound on the ink flow path pattern and the surface of the substrate in this manner, the coating resin layer 6 is dissolved in a solvent as appropriate to dissolve the coating resin layer 6 as shown in FIG. It is formed by a known spin coating method, roll coating method, or the like.

As the coating resin layer 6, a resin composition containing at least a cationically polymerizable epoxy resin and an aromatic onium salt is used. Specifically, as a cationically polymerizable epoxy resin, a reaction product of bisphenol A and epochlorhydrin, a reaction product of phenol novolac or o-cresol novolac and epichlorohydrin, JP-A-60-161973, JP-A-60-161973. Examples thereof include polyfunctional epoxy resins having an oxycyclohexane skeleton described in JP-A-63-221121, JP-A-64-9216, and JP-A-2-140219. On the other hand, examples of the aromatic onium salt include aromatic iodonium salts and aromatic sulfonium salts [J. P
OLYMER SCI: Symposium No56
383-395 (1976)], SP-170, SP-150 provided by Asahi Denka Kogyo KK, and the like. In these resin compositions, the aromatic onium salt is decomposed by light irradiation to initiate cationic polymerization of the epoxy resin, whereby a cured film can be formed.

By the way, since this cured film serves as an ink flow path forming member of the ink jet head, it is required to have high strength as a structural material and adhesion to the substrate surface. The cationically polymerized cured product of the epoxy resin used in (1) generally gives a cured coating film with a high crosslink density, but the adhesion to the substrate surface is not sufficient when considering long-term use as an inkjet head. I can not say. On the other hand, in the above-mentioned JP-A-6-286149 proposed by the inventors of the present application, in order to improve the adhesion to the substrate, the resin composition contains copper triflate and further the cured density of the epoxy resin. It has been proposed to improve the adhesion and obtain good adhesion to the substrate. However, the addition of copper triflate may cause a new problem that the dark reaction gradually progresses even at room temperature, resulting in deterioration of stability over time of the resin composition. That is, even at room temperature, the aromatic onium salt and copper triflate slightly react and the epoxy resin cures, so that the viscosity of the resin composition changes subtly. May change, resulting in lack of stability over time. On the other hand, it is possible to constantly monitor the change in viscosity and control the coating film thickness, but in this case, the process control becomes complicated and the problem of cost increase arises.

Since the addition of copper triflate or the like to the resin composition has a problem with respect to the stability of the resin composition over time in this manner, in the present embodiment, the resin composition is deposited by adhering it onto the substrate surface. It is possible to prevent the viscosity from changing and thereby to maintain the stability of the resin composition over time while maintaining good adhesion.

Next, the above-mentioned coating resin layer 6 is subjected to pattern exposure using a mask 7 as shown in FIG. The pattern-exposed coating resin layer 6 may be subjected to a heat treatment as needed to accelerate the reaction.

Next, the pattern-exposed coating resin layer 6 is formed.
Is developed using a suitable solvent, and as a result, the ink discharge port 8 is formed as shown in FIG. In addition, although the example of forming the ink ejection port by photolithography is shown here, a method such as processing by an excimer laser or etching by oxygen plasma may be used if necessary.

Next, as shown in FIG. 7, the ink flow path pattern 4 formed of a soluble resin layer is eluted. Finally, heat treatment is applied to the obtained inkjet head,
It is possible to completely react the copper triflate on the surface of the substrate with the coating resin layer to strengthen the adhesion at the substrate interface. Finally, the member 9 for supplying ink is joined to complete the ink jet head.

FIG. 9 is a schematic perspective view showing an example of an ink jet printing apparatus which can be used with the ink jet head manufactured by the above embodiment.

In the ink jet printing apparatus 100, the carriage 101 slidably engages with two guide shafts 104 and 105 extending in parallel with each other. As a result, the carriage 101 can be moved along the guide shafts 104 and 105 by a driving motor and a driving force transmission mechanism (not shown) such as a belt that transmits the driving force of the driving motor. The carriage 101 has the inkjet head obtained as described above, and an inkjet unit 10 having an ink tank as an ink container for storing the ink used in this head.
3 is installed.

That is, the ink jet unit 103
Is black (Bk), cyan (C), magenta (M)
Four heads for respectively ejecting inks of four colors of yellow and yellow (Y) and tanks provided corresponding to these heads are mounted on the carriage 101 as an inkjet unit 103. The heads and the tanks are detachable from each other, and are provided so that only the tanks can be replaced for each individual ink color or the like as needed when the ink in the tanks runs out. Of course, only the head can be replaced if necessary. The structure for attaching and detaching the head and the tank is not limited to the above example, and it goes without saying that the head and the tank may be integrally molded.

The paper 106 as a print medium is inserted from an insertion port 111 provided at the front end of the apparatus, the conveyance direction thereof is finally reversed, and the paper 106 is conveyed to the lower part of the moving area of the carriage 101 by the feed roller 109. It As a result, the head mounted on the carriage 101 prints on the print area on the paper 106 supported by the platen 108 as the head moves.

As described above, printing is performed on the entire paper 106 while alternately repeating the printing of the width corresponding to the width of the ejection opening arrangement of the head and the feeding of the paper 106 as the carriage 101 moves, and the paper 106 is printed. Is discharged to the front of the device.

At the tip of the movable area of the carriage 101, there is provided a recovery system unit 110 which can face the heads on the carriage 101 and the lower portions thereof so that the ejection ports of the heads can be used when recording is not performed. It is possible to perform an operation of capping, an operation of sucking ink from the ejection port of each head, and the like. The predetermined position of the left end is set as the home position of the head.

On the other hand, at the right end of the apparatus, an operation section 107 having a switch and a display element is provided. The switches here are used when turning on / off the power of the apparatus and setting various print modes, and the display element is used to display various states of the apparatus.

[0034]

EXAMPLE In this example, an ink jet head was prepared according to the procedure shown in FIGS. First,
The ink supply port 3 was formed by blasting on the silicon substrate 1 on which the electrothermal converting element 2 was formed as an ink ejection pressure generating element (FIG. 1). Next, polyisopropenyl ketone (ODUR1010 manufactured by Tokyo Ohka Kogyo Co., Ltd.) was applied onto PET as a resin layer that can be dissolved on the substrate and dried to form a dry film, which was transferred by lamination.

ODUR-1010 was used after being concentrated because the solid content concentration is low and a thick film cannot be formed as it is. Then, after prebaking at 120 ° C. for 20 minutes,
The ink flow path was patterned using a Canon mask aligner PLA521 (height of the ink flow path pattern layer 4 shown in FIG. 2 was 12 μm). Then ethanol 10
A solution obtained by dissolving 1 part of silane coupling material A-187 (manufactured by Nippon Unicar Co., Ltd.) and 2 parts of copper triflate with respect to 0 part was spin-coated on the ink flow path pattern 4 and the substrate 1 to form copper on the substrate surface. Triflate was attached (Figure 3). Next, the resin composition shown in Table 1 below was dissolved in xylene at a concentration of 50 wt%, and a coating resin layer was formed by spin coating (FIG. 4).

[0036]

[Table 1]

Next, pattern exposure (PLA521) for forming ink ejection ports is performed (FIG. 5), and heat treatment (90 ° C. for 10 minutes) to accelerate the curing reaction is performed. The heat treatment here is light irradiation. The effect of accelerating the curing by the copper compound is almost negligible. Further, by developing with a mixed solvent of methyl isobutyl ketone / xylene, an ink ejection port was formed (FIG. 6).

Further, the entire surface of the substrate is exposed (PLA521)
Then, the ODUR forming the ink flow path pattern was decomposed, eluted with methyl isobutyl ketone / xylene, and further heat-treated (200 ° C. for 1 hour) to obtain an inkjet head (FIG. 7). By this heat treatment at 200 ° C./1 Hr, it is possible to form a nozzle material having excellent physical properties in which the reaction with the epoxy resin / onium salt is promoted by the copper compound.

The ink jet head thus obtained was used for pure water / diethylene glycol / isopropyl alcohol / urea / black dye hood black 2 = 74.5 / 1.
When a pressure cooker test (PCT 120 ° C., 2 atm for 30 hours) was performed by immersing in a 5/5/3 / 2.5 ink, there was no peeling of the coating resin layer serving as the ink flow path forming member from the substrate surface. It was not observed. On the other hand, in the process of this example, an ink jet head prepared without adding copper triflate during the silane coupling treatment was subjected to the same PCT test as above,
Interference fringes were observed at a part of the interface between the coating resin layer and the substrate surface, and it was found that the adhesion was not sufficient.

Further, when a member for supplying ink was arranged in the ink jet head prepared in this example and recording was performed using the ink having the above composition, a high quality printed matter could be obtained. Further, when the head was filled with ink and recording was performed again after a storage test at 60 ° C. for 3 months, no deterioration of the printed matter was observed.

[0041]

As described above, according to the present invention, the aromatic onium salt and the copper compound are thermally reacted to initiate the cationic polymerization reaction of the epoxy resin. Also,
Aromatic onium salts can independently initiate cationic polymerization by light irradiation. For example, pattern exposure is performed, and heat treatment is performed after pattern formation, whereby the cationic polymerization reaction of the epoxy resin / onium salt is performed by a copper compound. A nozzle material that promotes and has excellent cured physical properties can be obtained.

Here, if the above-mentioned resin layer contains a copper compound, the dark reaction between the aromatic onium salt and the copper compound gradually progresses, so that the viscosity of the epoxy resin composition, etc. over time. However, when applied to the manufacture of an inkjet head, strict process control is required.

Therefore, as shown in the above structure, a resin layer composed of an epoxy resin / aromatic onium salt is formed as an ink flow path forming member of an ink jet head, and a copper compound and a silane cup are previously formed on the substrate side before forming the resin layer. Rin
By attaching the coating agent , good adhesion between the resin layer and the substrate can be obtained by the heat treatment after forming the resin layer.

As a result, an ink jet head having excellent adhesion between the substrate and the ink flow path forming member can be manufactured by a simpler means.

[Brief description of drawings]

FIG. 1 is a perspective view schematically showing a substrate of an inkjet head according to an embodiment of the present invention.

FIG. 2 is a schematic cross-sectional view showing a step of forming an ink flow path pattern on the substrate with a soluble resin layer.

FIG. 3 is a schematic cross-sectional view showing a step of further depositing a copper compound on the substrate surface.

FIG. 4 is a schematic cross-sectional view showing a step of forming a coating resin layer for the ink flow path forming member.

FIG. 5 is a schematic cross-sectional view showing a step of performing pattern exposure of an ink ejection port on a coating resin layer.

FIG. 6 is a schematic cross-sectional view showing a step of developing the coating resin layer patterned in the above step.

FIG. 7 is a schematic cross-sectional view showing a step of eluting an ink flow path pattern of a soluble resin.

FIG. 8 is a schematic cross-sectional view showing a step of attaching an ink supply member.

FIG. 9 is a schematic perspective view showing an example of an inkjet printing apparatus using the inkjet head obtained by the manufacturing method of the above embodiment.

[Explanation of symbols]

1 substrate 2 Ink ejection pressure generating element 3 ink supply port 4 Ink flow path pattern made of soluble resin 5 Copper compound 6 Coating resin layer 7 mask 8 ink outlets 9 Ink supply member

Claims (7)

(57) [Claims] 1. A copper compound and a silane cup are formed on a surface of a substrate on which an element for generating a pressure for ejecting ink is formed.
A step of attaching a solution containing a ring agent, and a step of forming a resin layer forming an ink flow path forming member on the substrate to which the solution containing a copper compound and a silane coupling agent is attached, The method for producing an inkjet head, wherein the resin composition forming the resin layer contains at least a cationically polymerizable epoxy resin and an aromatic onium salt. 2. A step of forming an ink flow path pattern with a soluble resin on a part of a substrate on which an element for generating a pressure for ejecting ink is formed, and a copper compound on the surface of the substrate . And silane coupling agent
A step of depositing a solution , a step of forming a resin layer forming an ink flow path forming member on the substrate to which the solution containing the copper compound and the silane coupling agent is attached, and A step of curing by irradiation, a step of forming an ink discharge port at a location corresponding to the element of the ink flow path forming member, a step of eluting an ink flow path pattern formed of the soluble resin, The method of manufacturing an inkjet head, wherein the resin composition forming the resin layer contains at least a cationically polymerizable epoxy resin and an aromatic onium salt. 3. The method for manufacturing an inkjet head according to claim 1, wherein the copper compound is copper triflate. 4. The inkjet head according to claim 1, further comprising a step of applying thermal energy to the copper compound adhered on the substrate and the ink flow path forming member. Manufacturing method. 5. An ink jet head manufactured by the manufacturing method according to any one of claims 1 to 4. 6. The ink jet head according to claim 5, wherein the element is an electrothermal conversion element. 7. An ink jet printing apparatus comprising the ink jet head according to claim 5 or 6.