JPH11138817A - Liquid-jet head and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To lessen generation of dust and improve reliability by forming a through hole at a coat resin layer to remove a resin layer to be larger by a specific value than a base in a liquid-jet head formed with the dissoluble resin layer totally removed. SOLUTION: Ink discharge energy-generating elements 1 are arranged on a substrate 2 of a liquid-jet recording head. A pattern 3 to be an ink flow passage and a pattern 4 to be a base are formed of a dissoluble resin on the substrate. A coat resin layer 5 is formed on the resin layers 3, 4, where ink discharge openings 6 are formed. A hole 8 is formed to be larger by 5 μm or more or smaller by 5 μm or more than the base. The substrate 2 is chemically etched, whereby an ink feed opening 7 is formed. The resin layers 3, 4 are dissolved out of the ink discharge openings 6, ink feed opening 7 and through holes 8. The ink flow passage and a foam chamber are thus formed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention
The present invention relates to an ink jet recording head for generating a recording liquid (ink) droplet used in a recording method (referred to as “ink jet”), and a method of manufacturing the same.

[0002]

2. Description of the Related Art The ink jet recording system has a problem that noise generation at the time of recording is extremely small to a negligible level, is capable of high-speed recording, can be fixed on so-called plain paper, and requires special processing. In recent years, it has become very popular in that it can be used for recording without the need.

[0003] Among the ink jet recording heads, those in which ink droplets are ejected in a vertical direction to a substrate on which an ink ejection energy generating element is formed are referred to as "side shooter type recording heads". The present invention relates to a type of side shooter type recording head.

[0004] JP-A-4-10940, JP-A-4-10940
The ink jet recording head (FIG. 5) described in Japanese Patent Application Laid-Open No. 10941 and Japanese Patent Application Laid-Open No. Hei 4-10942 can discharge ink droplets by communicating bubbles generated by heating a heating resistor with the outside air. Features.
In these recording heads, a method of manufacturing a conventional side shooter type head (for example, Japanese Patent Application Laid-Open No. 62-233491).
It is possible to shorten the distance between the ink ejection energy generating element and the orifice and easily achieve small droplet recording, which has been difficult in the present specification, and can respond to the recent demand for high-definition recording. It is. In the ink jet recording head manufactured according to these inventions, FIG.
As shown in (a) to (d), a coating resin layer 5 ′ serving as an orifice plate is applied by spin coating or the like on a substrate on which a soluble resin layer 3 is formed in a pattern serving as an ink flow path. The orifice plate is formed along the step pattern of the dissolvable resin layer 3, and the thickness of the orifice plate varies between a thick portion and a thin portion. When a recording head having such a structure is used, the reliability of the thin portion of the orifice plate is deteriorated, and the life of the recording head is shortened. Further, since the ink ejection amount is determined by the distance between the heating resistor 1 for generating ink ejection energy and the orifice surface, small droplet recording, which is one of the effective means for high-definition recording, is stably performed. That becomes very difficult.

As a means for solving the above-mentioned problems, the present applicant has proposed a method of forming a base pattern on the outer periphery of an ink flow path pattern with a dissolvable resin layer in order to form an orifice plate flat. And applied for a patent earlier. In the present invention, as shown in FIG. 5C, a base pattern 4 formed of a dissolvable resin layer and a through-hole pattern 8 for removing the base part 4 are formed to have the same size and width. However, the V portion in FIG. 5C and the V portion in FIG.
6 (a), 6 (b) and 7 which are schematic enlarged views of the VI section.
As shown in (a) and (b), when there is a deviation in the patterning accuracy between the base 4 formed of a dissolvable resin layer and the coating resin layer 5 forming an orifice plate, the minute projections 10 are formed. it can. The minute protrusions cause dust due to cracks during all processes including the removal of the base portion 4 until the ink jet recording head is completed, and during the period of repeated use as the ink jet recording head. The term “patterning accuracy” as used herein includes variations in pattern formation width, positioning accuracy during pattern formation, and the like. When dust is generated in the ink jet recording head, the dust moves with the flow of the ink liquid, clogs in the ink flow path or the ink discharge port, and print unevenness due to ink droplets flying on the recording paper. Also, non-ejection in which ink droplets do not fly at all.

[0006]

SUMMARY OF THE INVENTION The present invention has been made to improve the prior application in view of the above-described problems, and has a high reliability, a side shooter type ink jet recording head with less generation of dust. It is intended to provide a manufacturing method thereof.

[0007]

The present invention to achieve the above object is as follows. 1. In a liquid jet recording head in which ink droplets are ejected in a direction perpendicular to a substrate surface having a heating element, the flow path pattern is formed on the substrate together with an ink flow path pattern made of a soluble resin layer. Forming a pattern of the dissolvable resin layer serving as a base for flattening a coating resin layer serving as an orifice plate formed thereon, and forming a flat resin layer on the ink flow path pattern and the base pattern After forming, the liquid ejecting head obtained by removing all the dissolvable resin layers constituting the both patterns, provided on the coating resin layer for removing the dissolvable resin layer that became the base A liquid jet recording head, wherein the through hole is formed to be larger than or smaller than the base by 5 μm or more.

[0008] 2. The following steps (1) A pattern of a dissolvable resin layer serving as an ink flow path on a substrate on which a heating resistor is formed, and a base for forming a coating resin serving as an orifice plate on the resin layer flat. (2) forming a flat coating resin layer on the two soluble resin layer patterns, and (3) forming a flat coating resin layer on the two dissolvable resin layer patterns. A step of forming an ink discharge port, (4) a step of forming a through hole in the coating resin layer, which is sufficiently larger or considerably smaller than the base, for removing the dissolvable resin layer serving as the base, (5) 2. The method for manufacturing a liquid jet head according to the above item 1, comprising at least a step of forming an ink supply port in the substrate, and (6) a step of dissolving and removing the soluble resin layer.

3. 3. The method according to the above item 2, wherein the steps (3) and (4) are performed simultaneously.

[0010]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1A to FIG. 3D and FIG.
(D) is a schematic sectional view showing a basic manufacturing process of the liquid jet recording head according to the present invention.

The substrate 2 shown in FIG. 1 and FIG.
A desired number of ink ejection energy generating elements 1 such as heating resistors (electrothermal conversion elements) are arranged thereon. Next, a pattern 3 serving as an ink flow path and a pattern 4 serving as a base are formed of a dissolvable resin layer on the substrate 2 including the ink ejection energy generating element 1. The dissolvable resin layer may be formed into a pattern by, for example, laminating a dry film, applying a resist by spin coating, or the like, and then exposing / developing with, for example, ultraviolet light or Deep-UV light.

Specific examples include polymethyl isopropenyl ketone (ODUR-10 manufactured by Tokyo Ohka Kogyo Co., Ltd.).
10) is applied by spin coating and dried, and then
A pattern is formed by exposing and developing with p-UV light.

Next, as shown in FIGS. 1 and 3B, a coating resin layer 5 is formed on the dissolvable resin layers 3 and 4 by spin coating or the like. At this time, the coating resin layer 5
Since the base 4 made of a soluble resin layer is formed, the upper surface of the ink flow path 3 can be formed flat. Further, an ink discharge port 6 is formed in the coating resin layer 5 (FIG. 1 and FIG. 3C). The through-hole pattern 8 for removing the base 4 made of the dissolvable resin layer is formed simultaneously or at the same time by the same method. Here, the size of the through hole pattern 8 is sufficiently larger than the pattern of the base portion 4 made of the soluble resin layer (FIG. 1).
Or, by forming the through hole 8 very small (FIG. 3), even if the patterning accuracy of the through-hole 8 is considerably shifted, the minute protrusions 10 shown in FIGS. Here, “sufficiently large” and “substantially small” mean that the protrusions on the inner wall of the through hole after dissolving and removing the resin layer, which may occur when the pattern of the through hole 8 is made equal to the base portion, are avoided. Size, preferably 5 μm or more, more preferably 10 μm
It is only necessary that “large” and “small” be at least m.
The ink ejection port 6 and the through-hole 8 can be formed, for example, by exposure to ultraviolet light, Deep-UV light, or the like. More specifically, it is formed by applying a negative resist by spin coating, drying, pattern exposure with ultraviolet rays, and developing.

Next, an ink supply port 7 is provided in the substrate 2. The ink supply port 7 is formed by chemically etching the substrate. For example, an Si substrate is used as the substrate 2, and the substrate 2 is formed by anisotropic etching using a strong alkaline solution such as KOH, NaOH, or TMAH ((d) in FIGS. 1 and 3). As a more specific example, the crystal orientation is <11
TMAH22 in which the thermal oxide film formed on the Si substrate of No. 0> was patterned and the Si substrate was heated to 80 ° C.
The ink supply port 7 is formed by etching with a 10% solution for about ten hours.

The ink supply port is formed before the formation of the ink flow path pattern and the pattern serving as the base (FIG. 1, (a)) or the formation of the ink discharge port (FIG. 1, (c)). It is also possible to do.

Subsequently, as shown in FIG. 1D, the dissolvable resin layers 3 and 4 are eluted from the ink discharge port 6, the ink supply port 7, and the through-hole 8 for removing the resin layer. Thereby, an ink flow path and a foaming chamber are formed. The method of removing the soluble resin layers 3 and 4 is De
After performing the entire surface exposure with the ep-UV light, development and drying may be performed, and if necessary, ultrasonic immersion during the development may be sufficient.

Here, it is conceivable to leave the base portion 4 without removing the through hole 8 in order to remove the soluble resin layer. In this case, the above-mentioned ODUR-1010 has a heat deformation temperature of 110. ° C, the orifice plate is likely to be deformed or damaged by heating exceeding this temperature during a subsequent curing step or the like. Therefore, the step of removing the base portion composed of the soluble resin layer in the present configuration is essential.

The substrate 2 on which the nozzle portion has been formed by the above steps is separated and cut by a dicing saw or the like, formed into chips, and subjected to electrical bonding (not shown) for driving the heating resistor 1. The ink jet recording head is completed by connecting the chip tank members for supplying the ink.

With such a structure according to the present invention, it is possible to provide an ink jet recording head which has very little deterioration in print quality due to generation of dust, has high reliability, and can stably perform small droplet recording. Become.

The present invention has an excellent effect when applied to a bubble jet type recording head among ink jet recording heads.
0, JP-A-4-10941, JP-A-4-1
It is most suitable for the recording head of the method described in Japanese Patent No. 0942. In each of these publications, a drive signal corresponding to recording information is applied to an ink ejection energy generation element (electrothermal conversion element) to generate thermal energy that gives the electrothermal conversion element a sharp temperature rise exceeding the nucleate boiling of ink. Then, bubbles are formed in the ink, and the bubbles are communicated with the outside air to discharge ink droplets. In these methods, small ink droplets (50 pl or less) can be ejected, and the ink liquid in front of the heater is ejected. Therefore, the volume and speed of the ink droplets are stabilized without being affected by temperature, and high quality is achieved. Image can be obtained.

The present invention is effective as a full-line type recording head capable of simultaneously recording over the entire width of the recording paper, and is also effective for a color recording head in which recording heads are integrated or a plurality of recording heads are combined.

[0023]

EXAMPLES The present invention will be further described below with reference to examples, but these examples do not limit the present invention.

Embodiment 1 In Embodiment 1, the ink jet recording head having the structure shown in FIG. 2 and FIGS.
It was prepared according to the procedures shown in (a) to (d). At this time, FIG. 2 shows an AA ′ cross section of FIG. 8B. In addition, Y of the base part 4 in FIG. 2 was formed with a width of 100 μm, and X of the through hole 8 was formed with a width of 150 μm. Pure water / diethylene glycol /
When printing was performed at an ejection frequency f = 15 kHz using an ink liquid consisting of lithium isopropyl alcohol / lithium acetate / black dye food black 2 = 79.4 / 15/3 / 0.1 / 2.5, it was very high. High quality printing was obtained.

Further, assuming that this recording head is used for a long period of time, the recording head is stored at 60 ° C. in an ink atmosphere.
Using a recording head after performing a storage test for one month, f = 15
As a result of printing at kHz, no adverse effect on the ejection characteristics was observed at all, and good printing was obtained.

On the other hand, when printing was carried out at f = 15 kHz using the same ink liquid by the ink jet recording head shown in the conventional example, the ink liquid did not fly straight on the recording medium, and a streak due to a twist or a design Blurring was caused in some of the nozzles due to the fact that the ink ejection amount did not fly according to the value, resulting in low-quality print recording.

Embodiment 2 In Embodiment 2, an ink jet recording head having the structure shown in FIGS. 4 and 8A and 8B is used in the ink jet recording head shown in FIG.
It was prepared according to the procedures shown in (a) to (d). At this time, FIG. 4 shows a cross section taken along the line AA ′ of FIG. 8B. In addition, Y of the base part 4 of FIG. Using the ink liquid composed of pure water / diethylene glycol / lithium isopropyl alcohol acetate / black dye food black 2 = 79.4 / 15/3 / 0.1 / 2.5, the ejection frequency f = When printing was performed at 15 kHz, very high quality printing was obtained.
Further, assuming that the recording head was used for a long period of time, as a result of performing print recording at f = 15 kHz using the recording head after performing a storage test in the ink at 60 ° C. for 3 months, it was found that the ejection characteristics No adverse effects were seen,
A good print record was obtained.

[0028]

As described above, according to the present invention,
The following effects can be obtained. That is, it is possible to provide a highly reliable ink jet recording head capable of stably recording small droplets with extremely little deterioration in print quality due to generation of dust.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view showing an example of a basic manufacturing process of a liquid jet recording head of the present invention.

FIG. 2 is a schematic sectional view illustrating a characteristic portion of the liquid jet recording head of the present invention shown in FIG.

FIG. 3 is a schematic sectional view showing another example of the basic manufacturing process of the liquid jet recording head of the present invention.

FIG. 4 is a schematic sectional view illustrating a characteristic portion of the liquid jet recording head of the present invention shown in FIG.

FIG. 5 is a schematic cross-sectional view illustrating an example of a manufacturing process of a conventional liquid jet recording head.

6 is a schematic cross-sectional view illustrating an example of a problem of the conventional liquid jet recording head shown in FIG.

7 is a schematic cross-sectional view illustrating another example of the problem of the conventional liquid jet recording head shown in FIG.

FIG. 8 is a schematic plan view showing a basic mode of the liquid jet recording head of the present invention.

FIG. 9 is a schematic cross-sectional view showing another example of the manufacturing process of the conventional liquid jet recording head.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ink discharge energy generating element 2 Substrate 3 Soluble resin layer (ink flow path part) 4 Soluble resin layer (base part) 5, 5 'Coating resin layer (orifice plate) 6 Ink discharge port 7 Ink supply port 8 Through hole for removal of soluble resin layer

Claims (5)

[Claims] 1. A liquid jet recording head in which ink droplets are ejected in a direction perpendicular to a surface of a substrate having a heating element, wherein a pattern for an ink flow path formed of a dissolvable resin layer is formed on the substrate. Forming a pattern of the dissolvable resin layer which becomes a base for flattening a coating resin layer which becomes an orifice plate formed on the flow path pattern, and forming the ink flow path pattern and a pattern which becomes a base. After forming a flat resin layer on the liquid ejecting head formed by removing all the soluble resin layer constituting the two patterns, the liquid ejecting head for removing the soluble resin layer that became the base A liquid jet recording head, wherein a through hole provided in the coating resin layer is formed to be 5 μm or more larger than the size of the base. 2. A liquid jet recording head in which ink droplets are ejected in a direction perpendicular to a surface of a substrate having a heating element, the ink jet recording head including a pattern for an ink flow path made of a soluble resin layer on the substrate. Forming a pattern of the dissolvable resin layer serving as a base for flattening a coating resin layer serving as an orifice plate formed on the flow path pattern, and forming a pattern on the ink flow path pattern and a base serving as a base. A liquid ejecting head formed by forming a flat resin layer and then removing all dissolvable resin layers constituting the two patterns, wherein the coating for removing the dissolvable resin layer serving as a base is provided. A liquid jet recording head, wherein a through hole provided in the resin layer is formed to be smaller than the size of the base by 5 μm or more. 3. The following steps (1) A pattern of a dissolvable resin layer serving as an ink flow path and a coating resin serving as an orifice plate are formed flat on the substrate on which the heating resistor is formed. (2) forming a flat covering resin layer on the two dissolvable resin layer patterns, and (3) forming the flat covering resin layer on the two dissolvable resin layer patterns. (4) a step of forming an ink discharge port in the coating resin layer, and (4) a step of forming a through hole sufficiently larger than the base for removing the dissolvable resin layer serving as the base in the coating resin layer; 2. The method according to claim 1, further comprising: (a) forming an ink supply port in the substrate; and (6) dissolving and removing the soluble resin layer. 4. The following step (1): A pattern of a dissolvable resin layer serving as an ink flow path and a coating resin serving as an orifice plate are formed flat on the substrate on which the heating resistor is formed. (2) forming a flat covering resin layer on the two dissolvable resin layer patterns, and (3) forming the flat covering resin layer on the two dissolvable resin layer patterns. (4) a step of forming an ink discharge port in the coating resin layer, (4) a step of forming, in the coating resin layer, a through hole considerably smaller than the base for removing the dissolvable resin layer serving as the base; 3. The method according to claim 2, further comprising: (a) forming an ink supply port in the substrate; and (6) dissolving and removing the soluble resin layer. 5. The method according to claim 3, wherein steps (3) and (4) are performed simultaneously.