JPH1134339A - Liquid jet recording head and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a liquid jet recording head which can be delivered immediately upon completion by cleaning the liquid channel and the nozzle with an alkaline, acid or organic solvent or the like, before being filled with a recording liquid ink, thereby eliminating instability of initial printing/recording due to an unspecifiable cause. SOLUTION: A liquid channel forming material 4, e.g. epoxy resin, acryl resin, unsaturated polyester resin, polyurethane resin or the like, is laminated on a substrate 1 having a solid layer 3 while covering the solid layer 3. A desired liquid channel 5 is formed at a desired position on the substrate 1 provided with jet energy generating elements 2 thus constituting a liquid jet recording head. Furthermore, an alkali, e.g. aqueous solution of caustic soda, lithium acetate or the like, an acid, e.g. aqueous solution of hydrochloric acid, nitric acid, sulfuric acid or the like, and a solvent, e.g. DMSO, NMP, 2 pyrrolidone, ethyl Cellosolve, 3-methoxy propionic acid methyl or the like, are fed through the liquid channel 5 and the nozzle for cleaning, thus completing a recording head.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a method of manufacturing a liquid jet recording head for generating small droplets of a recording liquid used in an ink jet recording system.

[0002]

2. Description of the Related Art A liquid jet recording head applied to an ink jet recording system (liquid jet recording system) generally has a fine recording liquid discharge port (orifice), a liquid flow path, and a liquid provided in a part of the liquid flow path. A discharge energy generating unit. Conventionally, as a method of producing such a liquid jet recording head, for example, using a substrate such as glass or metal,
A method is known in which fine grooves are formed on the substrate by processing means such as cutting or etching, and then the substrate on which these grooves are formed is joined to another appropriate plate to form a liquid flow path. .

Further, as a new manufacturing method, a step of providing a solid layer in a pattern of a liquid flow path on a substrate, and providing at least a part of a liquid flow path forming material on the substrate on which the solid layer is provided. Fixing, a method of manufacturing a liquid jet recording head including a step of removing the solid layer from the substrate,
For example, it has been proposed in JP-A-61-154947.

According to the manufacturing method disclosed in the above-mentioned publication, a uniform discharge port shape can be formed with high accuracy, and the solid layer is filled in the liquid flow path during most of the manufacturing process. And a liquid jet recording head can be manufactured with high yield.

However, when the solid layer is completely removed from the fine liquid flow path, if the liquid layer is completely removed, the liquid layer material is damaged and cracks or swelling occur in the liquid flow path material. Or peeling from the substrate may occur. Therefore, as the liquid for removing this kind of solid layer, a solvent having little effect on the liquid flow path material is used. For this reason, in the manufacturing process of the liquid jet recording head, in practice, the completed head is filled with ink or the like as a recording liquid and left for a certain period of time to generate minute residues of the solid layer and various processes. So-called "dirt"
May need to be washed.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned points, and is a novel liquid jet recording head capable of providing a liquid jet recording head which is inexpensive, precise and highly reliable. The purpose of the present invention is to provide a method for manufacturing a recording head, and to perform a time-consuming and troublesome cleaning process of a flow path and a nozzle in a short period of time such as filling a recording liquid ink or the like for a relatively long time. It is an object.

Another object of the present invention is to provide a liquid jet recording head which has little interaction with a recording liquid and is excellent in mechanical strength and chemical resistance.

Furthermore, a method for manufacturing a liquid jet recording head in which restrictions on selection of a material for forming a liquid flow path are reduced, a margin of process conditions is widened, restrictions on apparatuses are reduced, and safety is taken into consideration. It is also an object of the present invention to provide

[0009]

Therefore, in the present invention, the above object is achieved by providing a liquid jet recording head and a method for manufacturing the same as described in any of the following items (1) to (6). What we are trying to achieve.

(1) A step of washing the inside of the liquid flow path and the nozzle with an alkali, an acid, an organic solvent or the like before filling the liquid flow path and the nozzle with the recording liquid ink. Manufacturing method of recording head.

(2) A step of providing a solid layer of a photosensitive material in a pattern of a liquid flow path on a substrate, and forming at least a part of the liquid flow path forming material on the substrate on which the solid layer is provided. In the method for manufacturing a liquid jet recording head including a step of providing and a step of removing the solid layer from the substrate, the method includes removing the solid layer, and filling the liquid flow path and the nozzle with the recording liquid ink. Cleaning the inside of the liquid flow path and the nozzle with an alkali, an acid, an organic solvent, or the like.

(3) The method for manufacturing a liquid jet recording head according to the above (2), wherein the photosensitive material is a positive resist solubilized by actinic rays.

(4) The method for manufacturing a liquid jet recording head according to the above item (2), wherein the liquid flow path constituting material is an epoxy resin.

(5) The method for manufacturing a liquid jet recording head according to the above (2), wherein the solid layer is a positive resist and the material for forming the liquid flow path is an epoxy resin.

(6) A liquid jet recording head manufactured by the manufacturing method according to any one of (1) to (5).

[0016]

According to the manufacturing method of the present invention as described above, it is possible to obtain a highly reliable liquid jet recording head in which the cleaning step is relatively simple.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to the drawings based on basic and specific examples.

[0018]

1 to 6 are schematic diagrams for explaining a basic embodiment of the present invention. Each of FIGS. 1 to 6 shows a liquid jet recording head according to the method of the present invention and its liquid jet recording head. An example of a manufacturing process procedure is shown. In this embodiment, an example of a liquid jet recording head having two orifices is shown. However, it goes without saying that the same applies to a liquid jet recording head having more orifices. .

First, in this embodiment, for example, a substrate 1 made of glass, ceramic, plastic, metal or the like is used as shown in a schematic perspective view of the substrate before the solid layer is formed in FIG.

The substrate 1 functions as a part of the liquid flow path constituent material, and may have any shape and shape as long as it can function as a support when laminating a solid layer and a liquid flow path constituent material described later. The material can be used without any particular limitation.

On these substrates 1, a desired number of liquid ejection energies 2 such as electrothermal transducers or piezoelectric elements are arranged (two in FIG. 1). By such a liquid discharge energy generating element 2, discharge energy for discharging a recording liquid droplet such as ink is given to the ink liquid, and image recording and printing are performed.

For example, when an electrothermal transducer is used as the liquid discharge energy generating element 2, the element heats a nearby recording liquid to generate discharge energy. Further, for example, when a piezoelectric element is used, ejection energy is generated by mechanical vibration of the element.

These elements 2 are connected to control signal input electrodes (not shown) for operating these elements. In general, various functional layers such as a protective layer are provided for the purpose of improving the durability of the ejection energy generating element 2 and the like. Of course, the provision of such a functional layer in the present invention does not matter. . Also,
In the present embodiment, the ejection energy generating element is disposed on the substrate 1 before the formation of the liquid flow path, but may be disposed at a desired timing.

Next, in a portion where a liquid flow path is to be formed on the substrate 1 including the liquid discharge energy generating element 2, for example, FIG.
A solid layer 3 as shown in (a) and (b) is formed. FIG. 2A is a schematic plan view of the substrate 1 after the formation of the solid layer 3, and FIG.
It is a typical sectional view of a substrate cut by a line.

As a material used for forming such a solid layer 3, a positive resist which is solubilized by irradiation with actinic rays is optimal.

The reasons are as follows: 1) This process has already been applied in the manufacture of ICs and printed circuit boards, and since it is a photolithography method, the alignment with the substrate 1 can be performed with high accuracy. Further, the shape of the formed pattern can be improved with good reproducibility. Particularly suitable for multi-nozzle construction.

2) Good removability. In particular, irradiation with actinic rays further improves the removability. If the molecular weight is increased by irradiation with actinic light, as in the case of a negative photoresist, the removal in the subsequent process may not be completely performed, which may lead to contamination in the nozzle. Such a thing is unlikely to occur with a mold resist.

Specifically, "OZATEC R-225" (trade name, Hoechst Japan KK) or the like as a positive type dry film resist, and "OZATEC PL-268" or "EL series" as a liquid positive type resist are used. (Trade name, Nippon Synthetic Rubber Co., Ltd.), "OFPR series", "PMER-P series", "ODUR series" (trade name, Tokyo Ohka Kogyo Co., Ltd.), "ZPP series" (trade name, Zeon Japan) Co., Ltd.).

The method of laminating these on the substrate 1 can be achieved by laminating using a hot roll laminator which is usually carried out at the time of manufacturing a printed board, as long as it is a dry film type. When a liquid type is used, spin coating, roll coating, curtain coating, screen printing, and the like can be applied. In the case of liquid, the solvent is removed after coating, so
It goes without saying that coating is performed in anticipation of a decrease in thickness.

The substrate 1 on which these positive resists are laminated is irradiated with actinic rays in a state where a photomask having a pattern corresponding to a liquid flow path is aligned with the substrate 1 and overlapped. Next, the solid layer 3 is formed by developing with a developing solution such as caustic soda. In addition, before laminating the liquid flow path constituting material 4 to be performed next, ultraviolet irradiation may be performed for the purpose of enhancing the removability of the solid layer 3 in a later step.

On the substrate 1 having the solid layer 3 formed in this way, a liquid flow path forming material 4 is laminated so as to cover the solid layer 3 as shown in FIG. Note that FIG.
FIG. 3 is a schematic cross-sectional view of the substrate 1 cut at the same position as in FIG. 2 after laminating the liquid flow path constituent materials.

As the material 4 for forming the liquid flow path, any material that can cover the solid layer 3 can be suitably used. Since it is a structural material as a recording head, it is preferable to select and use a material excellent in adhesiveness to the substrate 1, mechanical strength, dimensional stability, corrosion resistance and the like.

If such a material is specifically shown, a liquid curable material such as heat curing, ultraviolet curing and electron beam curing is preferable, and among them, epoxy resin, acrylic resin, diglycol dialkyl carbonate resin, unsaturated polyester resin , Polyurethane resin, polyimide resin, melamine resin, phenol resin, urea resin and the like are preferably used.

When the liquid curable material is used as the liquid flow path constituting member 4, these materials are applied by using known means such as curtain coat, roll coat, spray coat and the like. By such a method, it is laminated on the substrate 1 with a desired thickness. In application, it is preferable to perform degassing of these materials 4 and then avoid mixing of air bubbles.

Here, for example, as shown in FIG. 3, when laminating the liquid flow path forming material 4, when the above-mentioned liquid curable material is used, these curable materials are, for example, liquid liquid. In a state where the outflow and the flow are suppressed, if necessary, a pressing plate is stacked on the upper portion and cured under predetermined conditions (see FIG. 4 showing a schematic cross-sectional view of the substrate after the curable material is cured).

Next, the liquid layer 5 is formed by removing the solid layer 3 from the above-described substrate 1 on which the solid layer 3 and the liquid channel forming material 4 are laminated (see FIG. 6). As a solvent used for removing the solid layer 3, methyl lactate, ethyl lactate, and butyl lactate or a solvent containing methyl lactate, ethyl lactate, and butyl lactate as main components, or dimethyl sulfoxide, halogen, Hydrocarbons,
Examples include ether, alcohol, N-methylpyrrolidone, dimethylformamide, phenol, ethylene glycol monoethyl ether, water, and water containing a strong alkali. A surfactant may be added to these liquids as needed.

The means for removing the solid layer 3 is not particularly limited, but specifically, the substrate 1 is immersed in the solvent.
Can be immersed or, if necessary, sonication, spraying, heating, stirring, or other means for promoting removal.

FIG. 5 is a schematic sectional view of the liquid jet recording head cut at the same position as in FIG. 2 after the solid layer 3 is removed. FIG. 6 is a schematic perspective view of the liquid jet recording head after the liquid supply port 6 is provided prior to the dissolution and removal of the solid layer, and thereafter the solid layer is removed.

As described above, a liquid jet recording head in which a desired liquid flow path 5 is formed at a desired position on the substrate 1 on which the ejection energy generating elements 2 are provided. Further, in the embodiments of the present invention, alkalis such as caustic soda aqueous solution and lithium acetate aqueous solution, acids such as hydrochloric acid aqueous solution, nitric acid aqueous solution, nitric acid aqueous solution, DMSO, NMP, 2-pyrrolidone, ethyl cellosolve, methyl 3-methoxypropionate,
A solvent such as EGMEA is flowed through the liquid flow path 5 and the nozzles for cleaning to complete the recording head.

Hereinafter, more specific embodiments of the present invention will be described, and the gist of the present invention will be described in more detail.

Example 1 A liquid ejection recording head having a schematic perspective view shown in FIG. 6 was prepared according to the manufacturing procedure shown in FIGS.

First, a positive resist "OZATEC PL-26" is formed on a glass substrate 1 on which an electrothermal transducer (material HfB2) as a liquid discharge energy generating element 2 is formed.
8 "(trade name, Hoechst Japan K.K.), and a photosensitive layer having a thickness of 25 μm after drying was dried at 2700 rpm with a spinner.
The spin coating was performed at a rotation speed of m for 40 seconds. Fig. 6
And a portion excluding the portion where the liquid flow path is to be completed was irradiated with ultraviolet light of 1000 mJ / cm ² .

In this case, the length of the liquid flow path 5 was 1 mm, the nozzle density was 16 / mm, and the number of nozzles was 128. Next, spray development was performed with a 1% aqueous solution of caustic soda to form a relief solid layer 3 having a thickness of about 25 μm on a portion of the glass substrate 1 including the electrothermal transducer 2 where a liquid flow path was to be formed.

Next, in order to enhance the removability of the solid layer 3, an ultraviolet ray of 5000 mJ / cm ² was irradiated, and then a curable material having the following composition was laminated.

Adeka Optomer KRM-4210 (epoxy resin) (trade name, Asahi Denka Kogyo Co., Ltd.) Epolite 3002 (epoxy resin) (trade name, Kyoeisha Yushi Kagaku Kogyo Co., Ltd.) Adeka Optomer SP-170 (light) Polymerization initiator) (trade name, Asahi Denka Kogyo Co., Ltd.) As a method of lamination, coating was performed to a thickness of 50 μm using an applicator. This was irradiated with ultraviolet rays of 2000 mJ / cm ² , cured, and then cut at a position where an orifice was to be formed to expose an end face of a solid layer made of a positive resist.

Each of the substrates 1 having the exposed end faces was immersed in methyl lactate, washed in an ultrasonic cleaning tank for 10 minutes, and dried. As for the shape of the orifice, the shape before laminating the liquid flow path constituting material 4 was modeled as it was.
In addition, the liquid flow path constituent material 4 did not have any damage such as swelling, cracking, and peeling from the substrate.

Subsequently, a 3% aqueous solution of caustic soda was passed through the liquid flow path 5 and the nozzle to wash dirt. Further, these liquid jet recording heads were mounted on a recording apparatus main body, and recording was performed immediately after filling with an inkjet ink composed of pure water / glycerin / direct black 154 (water-soluble black dye) = 65/30/5. Printing was possible.

(Embodiment 2) As in Embodiment 1, FIG.
The liquid jet recording head having the configuration described above was prepared.

First, a glass substrate 1 to which a piezoelectric body (material PbTiO3) is adhered as the liquid ejection energy generating element 2
On top, liquid positive resist "PMER-AR900"
(Trade name, Tokyo Ohka Kogyo Co., Ltd.) 2500 by spinner
After spin coating at 50 rpm for 50 seconds, it was dried for 20 minutes. On this photosensitive layer, a mask having a pattern corresponding to 24 nozzles, a nozzle pitch of 0.25 mm, and a liquid flow path of 3 mm was overlapped.
Irradiation with ultraviolet light in an amount of J / cm ² was performed. Next, spray development was performed using a 1% aqueous solution of caustic soda to form a relief solid layer.

Next, in order to enhance the removability of the solid layer,
Irradiation of ultraviolet rays in an amount of 5000 mJ / cm ² was performed. The following steps were performed in the same manner as in Example 1 to construct a liquid jet recording head, and finally, NMP was passed through the liquid flow path 5 and the nozzles for cleaning. Swelling, cracking,
There was no damage such as peeling from the substrate. Furthermore, when recording was performed immediately after filling with the same inkjet ink as in Example 1, stable printing was possible.

<Comparative Example> Next, in order to verify the effects of the embodiments 1 and 2, a product equivalent to a conventional example for comparison was prepared and compared.

Comparative Example 1 A liquid jet recording head was prepared in the same manner as in Example 1 except that the final cleaning step was not performed. Printing (recording) was performed immediately after filling with the inkjet ink in the same manner as in Example 1.
There was no one in which good printing was obtained. However,
With the head 5 days after the ink was filled, good printing was obtained.

Comparative Example 2 A liquid jet recording head was prepared in the same manner as in Example 2 except that the final cleaning step was not performed. Printing was performed immediately after filling with the ink-jet ink in the same manner as in Example 2, but no print was obtained. However, after filling with ink, 6
Good printing was obtained with the head after the passage of days.

[0054]

As described above, the effects brought about by the present invention include the following items: 1) Instability of initial printing (recording) due to stains that cannot identify the cause. No product can be shipped immediately after the liquid recording head is completed.

2) The main steps for manufacturing the recording head are as follows:
Because of the so-called printing technology, that is, the fine processing technology using a photoresist, the fine density of the recording head can be formed in a desired pattern and very easily. It can be processed at the same time.

3) Since a material having excellent adhesiveness or mechanical strength to a recording solution using a corrosive / erodible aqueous solution or an organic solvent as a medium is used as a material for a recording head, the durability as a recording apparatus is improved. Performance or reliability can be improved.

4) The positioning of the main constituent parts can be easily performed and can be surely performed, and a recording head with high dimensional accuracy can be obtained with high yield.

5) A high density multi-array liquid jet recording head can be obtained by a simple method.

6) It is extremely easy to adjust the thickness of the groove wall constituting the liquid flow path, and a liquid flow path having a desired size can be formed according to the thickness of the solid layer.

7) Continuous and mass production is possible.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view of a substrate before a solid layer is formed.

FIGS. 2A and 2B are a schematic plan view of a substrate after a solid layer is formed and an AA cross-sectional view thereof.

FIG. 3 is a schematic cross-sectional view of a substrate after a liquid flow path constituent material is laminated.

FIG. 4 is a schematic cross-sectional view of a substrate after a liquid curable material is used as a liquid flow path constituent material after the material is cured.

FIG. 5 is a schematic cross-sectional view of a substrate after removing a solid layer.

FIG. 6 is a schematic perspective view of a liquid jet recording head in a completed state.

[Explanation of symbols]

 Reference Signs List 1 substrate 2 liquid discharge energy generating element 3 solid layer 4 liquid flow path constituent material 5 liquid flow path 6 liquid supply port

Claims (6)

[Claims] Before filling a recording liquid ink into a liquid flow path and a nozzle, said liquid flow path is filled with an alkali, an acid, an organic solvent or the like.
A method for manufacturing a liquid jet recording head, comprising a step of cleaning the inside of a nozzle. 2. A step of providing a solid layer of a photosensitive material in a pattern of a liquid flow path on a substrate, and providing at least a part of the liquid flow path forming material on the substrate on which the solid layer is provided. In the method for manufacturing a liquid jet recording head including a step and a step of removing the solid layer from the substrate, the solid layer is removed, the liquid flow path, before filling the recording liquid ink in the nozzle, A method for manufacturing a liquid jet recording head, comprising a step of cleaning the inside of the liquid flow path and the nozzle with an alkali, an acid, an organic solvent or the like. 3. The method according to claim 2, wherein the photosensitive material is a positive resist solubilized by actinic rays. 4. The method according to claim 2, wherein the material for forming the liquid flow path is an epoxy resin. 5. The method according to claim 2, wherein the solid layer is a positive type resist, and the material for forming the liquid flow path is an epoxy resin. 6. A liquid jet recording head manufactured by the manufacturing method according to claim 1.