JP2002331669A - Nozzle plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a nozzle plate in which leakage of ink due to incomplete joint is prevented by making uniform the pressure applied at the time of bonding the nozzle plate to a liquid chamber substrate. SOLUTION: The nozzle plate 1 comprises a first layer 2 formed by electroforming of Ni, and a second layer 3 formed on the first layer 2 by electroforming of Ni, wherein a nozzle hole 4 and an ink inflow groove 5 are formed in the nozzle plate 1, and a thin part 6 is formed over the entire region except the parts for forming the nozzle hole 4 and the ink inflow groove 5. More specifically, a thick part 7 is formed locally on the periphery of the nozzle hole 4 and the ink inflow groove 5 by concentrating electrolysis at the time of electroforming, and, since a similar thick part 7 is also formed locally on the periphery of the thin part 6, the nozzle plate 1 has a uniform thickness over the entire region. Since a pressure can be applied uniformly over the entire region of the nozzle plate 1 at the time of bonding the nozzle plate 1 to a liquid chamber substrate in which a liquid chamber is formed, occurrence of incomplete joint is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a nozzle plate, and more particularly, to a method in which a pressure applied at the time of joining with a liquid chamber substrate is made uniform to prevent the occurrence of ink leakage or the like due to a joining failure. Regarding the nozzle plate.

[0002]

2. Description of the Related Art An ink jet recording apparatus does not require processes such as development and fixing, and can perform recording in a non-contact manner. Therefore, color printing is easy, and noise during recording is extremely small. It has many advantages, such as high-speed printing, high ink flexibility, and the ability to use inexpensive plain paper, and is widely used in image forming apparatuses such as printers, copiers, and facsimile machines. ing.

Among the ink jet systems, a so-called drop-on-demand type, which discharges ink droplets only when print recording is required, is currently the mainstream because it does not require collection of ink droplets unnecessary for recording.

[0004] Such an ink jet recording apparatus generally has a nozzle plate in which a plurality of nozzles are formed, an ink liquid chamber in which each nozzle communicates, and an actuator arranged corresponding to each nozzle. The ink in the ink liquid chamber is pressurized by the displacement or heat generation of the actuator, and the ink droplets are ejected from the nozzle holes to perform recording on a recording material such as paper.

However, recent ink jet recording apparatuses are required to have high speed and high printing quality, and in order to achieve high speed and high printing quality, it is necessary to increase the number of nozzles and increase the density. When a piezoelectric element is used as an actuator, it is difficult to finely process the piezoelectric element and bond it to each of the diaphragms. In addition, the dimensional accuracy in the conventional machining causes large variations in print quality. Therefore, a method using a piezoelectric element cannot cope with high speed and high print quality.

Further, in the conventional method of heating ink, the ink is heated by a thin-film resistance heating element, so that it is possible to cope with multi-density and high-density nozzles. However, there has been a problem that the resistance heating element is easily damaged by rapid repetition of heating / cooling at the time of driving or an impact at the time of bubble disappearance, and the life of the ink jet head is short.

As a method for solving the above problems,
As a driving means of the actuator, there is a so-called electrostatic type in which a diaphragm is vibrated by using an electrostatic force to discharge ink, and the electrostatic type inkjet head can be reduced in size and density, Furthermore, it has the advantage of a long life.

[0008] Conventionally, the nozzle plate is manufactured by the manufacturing steps shown in FIGS. That is,
First, as shown in FIG. 8, a resist pattern 102 for nozzle holes is formed on a substrate 101 such as SUS (stainless steel), and a first layer 103 is formed by Ni electroforming. next,
As shown in FIG. 9, a resist pattern 104 for an ink supply groove and a nozzle hole is formed on a first layer 103 by a dry film resist (hereinafter, DFR), and a second layer 105 is formed by Ni electroforming. . After forming the second layer 105, the first layer 103 and the second layer 10
5 is peeled off to form the nozzle plate 100, and further, the resist pattern 102 and the resist pattern 1 of the DFR
04, the nozzle hole 106 and the ink inflow groove 1
The nozzle plate 100 on which the nozzles 07 are formed is completed.

[0009]

However, when a nozzle plate is manufactured by the above-described conventional method of manufacturing a nozzle plate, as shown in FIG. Since the electrode area at the time of electroforming is smaller than that of other parts, the current density becomes higher and the film thickness is locally increased. That is, the nozzle plate 100 includes the nozzle holes 106 and the ink inflow grooves 10.
7 has a thick portion 108 at the peripheral portion and a thin portion 109 at other portions.

As described above, when the film thickness is locally increased,
When the nozzle plate 100 is joined to a liquid chamber substrate 111 formed of silicon to define a liquid chamber 112, as shown in FIG. 12 and FIG. There is a problem that the pressing force is not evenly applied to the entire surface of the plate 100, a bonding failure occurs, and ink leakage or the like may occur. In particular, nozzle hole 1
In the case where the ink channel 06 and the ink inflow groove 107 are formed in a concentrated manner in a part of the nozzle plate 100, only the thickness of the part is increased, and the possibility of occurrence of bonding failure increases.

In order to manufacture the nozzle plate 100 by the above-described conventional manufacturing method, it is necessary to add a step of forming the thin portion 109 in addition to the step of forming the nozzle holes 106 and the ink inflow grooves 107. There is a problem that the number of 100 manufacturing steps increases.

Further, as shown in FIGS. 12 and 13,
The thin portion 109 of the nozzle plate 100 is
When the thin portion 109 overlaps the ridge of the first liquid chamber 112,
Then, a step 121 is generated in the liquid chamber 112. In the ink jet head, when the ink flows in the direction shown by the arrow in FIG. 12, such a stepped portion 121 causes a turbulent flow of ink and a pressure drop due to the sticking of air bubbles, thereby lowering the ink ejection efficiency. Or ink ejection failure occurs,
There is a problem that the quality of the printed image is reduced.

Therefore, the first aspect of the present invention is directed to a liquid chamber substrate formed with a plurality of liquid chambers filled with ink and connected to a plurality of nozzles and liquid chambers respectively communicating with the respective liquid chambers. An ink inflow groove for supplying ink is formed, and ink in the liquid chamber is formed by a change in pressure in the liquid chamber generated by a restoring force of a diaphragm formed in a part of each liquid chamber of the liquid chamber substrate and deformed by electrostatic force. By forming a thin portion having a predetermined thickness in a portion other than the portion where the nozzle hole and the ink inflow groove of the nozzle plate to be ejected from the nozzle are formed, the current density is concentrated when the nozzle plate is manufactured by electroforming. To provide a nozzle plate capable of distributing a locally thick portion over the entire nozzle plate so that a pressing force becomes uniform at the time of joining with a liquid chamber substrate and preventing occurrence of ink leakage or the like due to joining failure. It is an object.

According to a second aspect of the present invention, the thickness of the thin portion is approximately the same as the thickness of the ink inflow groove portion or a thickness which is an integral multiple of the thickness of the ink inflow groove portion. It is an object of the present invention to provide an inexpensive nozzle plate that can form a portion in the same process, simplifies the manufacturing process of the nozzle plate, and can prevent the occurrence of ink leakage or the like due to defective bonding.

According to the third aspect of the present invention, the thin portion is formed at a position deviating from the ridgeline position of the partition wall portion of the liquid chamber of the liquid chamber substrate, so that a step is generated at the junction between the thin portion and the liquid chamber. To prevent the occurrence of ink turbulence and the pressure drop due to the sticking of air bubbles, to prevent the ink ejection efficiency from being reduced and to prevent ink ejection failure from occurring, and to improve the quality of printed images. It is an object of the present invention to provide a nozzle plate.

[0016]

According to a first aspect of the present invention, there is provided a nozzle plate which is joined to a liquid chamber substrate having a plurality of liquid chambers filled with ink and communicates with each of the liquid chambers. A plurality of nozzles and an ink inflow groove for supplying the ink to the liquid chamber are formed, and are generated by a restoring force of a diaphragm formed in a part of each liquid chamber of the liquid chamber substrate and deformed by electrostatic force. In a nozzle plate that ejects ink in the liquid chamber from the nozzle by a change in pressure in the liquid chamber, a thin portion having a predetermined thickness is formed in a portion other than a portion where the nozzle hole and the ink inflow groove are formed. As a result, the above object is achieved.

According to the above arrangement, the ink is supplied to the plurality of nozzles and the plurality of liquid chambers which are joined to the liquid chamber substrate on which the plurality of liquid chambers to be filled with the ink are formed and communicate with the respective liquid chambers. An ink inflow groove is formed, and ink in the liquid chamber is ejected from a nozzle by a pressure change in the liquid chamber generated by a restoring force of a diaphragm formed in a part of each liquid chamber of the liquid chamber substrate and deformed by electrostatic force. Since a thin portion having a predetermined thickness is formed in a portion other than the portion where the nozzle hole and the ink inflow groove of the nozzle plate are formed, the local thickness due to current density concentration when the nozzle plate is manufactured by electroforming. By distributing the parts over the entire nozzle plate, the pressing force can be made uniform at the time of joining with the liquid chamber substrate, and the occurrence of ink leakage or the like due to joining failure can be prevented.

In this case, for example, as described in claim 2, the thin portion has a thickness approximately equal to the thickness of the ink inflow groove portion or an integral multiple of the thickness of the ink inflow groove portion. You may.

According to the above configuration, since the thin portion has a thickness approximately equal to the thickness of the ink inflow groove portion or an integral multiple of the thickness of the ink inflow groove portion, the ink inflow groove and the thin portion have the same thickness. A nozzle plate that can be formed in a process and that simplifies the manufacturing process of the nozzle plate and that can prevent the occurrence of ink leakage or the like due to poor bonding can be manufactured at low cost.

Further, for example, as described in claim 3, the thin portion may be formed at a position deviated from a ridgeline position of a partition of the liquid chamber of the liquid chamber substrate.

According to the above configuration, since the thin portion is formed at a position deviating from the ridgeline position of the partition wall portion of the liquid chamber of the liquid chamber substrate, a step is generated at the junction between the thin portion and the liquid chamber. Turbulence and the pressure drop due to the sticking of air bubbles can be prevented.
Ink ejection failure can be prevented from occurring, and the quality of a printed image can be improved.

[0022]

Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings. It should be noted that the embodiments described below are preferred embodiments of the present invention, and therefore, various technically preferable limitations are added. However, the scope of the present invention is not limited to the following description. The embodiments are not limited to these embodiments unless otherwise specified.

FIGS. 1 to 7 are views showing an embodiment of a nozzle plate of the present invention. FIG. 1 is a plan view and a view of a nozzle plate to which an embodiment of the nozzle plate of the present invention is applied. 2 is a cross-sectional view taken along the line BB of FIG.

In FIG. 1 and FIG.
Is formed by a first layer 2 formed by Ni electroforming and a second layer 3 formed by Ni electroforming on the first layer 2. An ink inflow groove 5 is formed. In the nozzle plate 1, a thin portion 6 is formed over the entire area other than the nozzle hole 4 and the ink inflow groove 5. That is, in the nozzle plate 1, due to the concentration of electrolysis at the time of electroforming, a local thick portion 7 is formed around the nozzle hole 4 and the ink inflow groove 5 in the same manner as in the related art. A similar locally thick portion 7 is also formed. The thin portion 6 is formed so as to be uniformly distributed in the nozzle plate 1 and has the same distribution density, pitch, and formation area as the nozzle holes 4 or the ink inflow grooves 5.

The nozzle plate 1 is manufactured by the following manufacturing steps. That is, first, as shown in FIG. 3, a resist pattern 21 for the nozzle holes 4 is formed on a substrate 20 such as SUS (stainless steel), and the first pattern is formed by Ni electroforming.
The layer 2 is formed.

Next, as shown in FIG. 4, on the first layer 2,
A resist pattern 22 for the ink inflow groove 5 and the nozzle hole 4 is formed by a dry film resist (hereinafter, DFR).
At this time, a resist pattern of the thin portion 6 is also formed in the same step, and then the second layer 3 is formed by Ni electroforming.
To form

After forming the second layer 3, the first
When the layer 2 and the second layer 3 are peeled off, and the resist pattern 21 and the resist pattern 22 of the DFR are peeled off, as shown in FIG. 5, the nozzle having the nozzle hole 4, the ink inflow groove 5 and the thin portion 6 is formed. Plate 1 is completed.
At this time, the thickness of the ink inflow groove 5 and the thickness of the thin portion 6 are the same.

As described above, in the nozzle plate 1 of the present embodiment, since the resist pattern of the ink inflow groove 5 and the thin portion 6 is formed in the same process, the thin portion 6 can be formed without increasing the number of manufacturing steps. Can be formed.

In the nozzle plate 1, since the thin portion 6 is formed over the entire area of the nozzle plate 1, the locally thick portion 7 is also formed over the entire area of the nozzle plate 1. The thickness of the nozzle plate 1 becomes uniform throughout.

Accordingly, as shown in FIGS. 6 and 7, when the nozzle plate 1 is joined to the silicon liquid chamber substrate 31 in which the liquid chamber 30 is formed, the pressure is uniformly applied to the entire area of the nozzle plate 1. Can be applied, and the occurrence of bonding failure can be prevented. As a result, it is possible to prevent the occurrence of ink leakage or the like due to a poor connection between the nozzle plate 1 and the liquid chamber substrate 31, and to improve the image quality of the formed image.

Then, the thin portion 6 of the nozzle plate 1 is
As shown in FIGS. 6 and 7, if the liquid chamber substrate 31 is formed so as to fit within the area of the liquid chamber 30 of the liquid chamber substrate 31 joined to the nozzle plate 1, there is no step in the ink inflow direction shown by the arrow in FIG. By preventing the occurrence of turbulence and the pressure drop due to the sticking of bubbles, the ink ejection efficiency can be improved, and the ink ejection performance can be improved.
The quality of the printed image can be further improved.

Although the invention made by the inventor has been specifically described based on the preferred embodiments, the invention is not limited to the above-described embodiment, and various modifications can be made without departing from the gist of the invention. It goes without saying that it is possible.

For example, in the above-described embodiment, the thin portion 6 is formed to have the same thickness as the thickness of the ink inflow groove 5, but the thickness of the thin portion 6 is not limited to this.
For example, the thickness may be an integral multiple of the thickness of the nozzle plate 1 in the ink inflow groove 5.

[0034]

According to the nozzle plate of the first aspect of the present invention, a plurality of liquid chambers, each of which is connected to a liquid chamber substrate on which a plurality of liquid chambers filled with ink are formed, communicates with each liquid chamber. An ink inflow groove for supplying ink to the nozzle and the liquid chamber is formed, and a pressure change in the liquid chamber generated by a restoring force of the vibration plate formed in a part of each liquid chamber of the liquid chamber substrate and deformed by electrostatic force is used. Since a thin portion having a predetermined thickness is formed in a portion other than the portion where the nozzle hole and the ink inflow groove of the nozzle plate for discharging ink in the liquid chamber from the nozzle are formed, the nozzle plate is manufactured by electroforming. Local thickness part due to current density concentration at the time of distribution over the entire nozzle plate,
The pressure can be made uniform when joining with the liquid chamber substrate,
It is possible to prevent the occurrence of ink leakage or the like due to poor bonding.

According to the nozzle plate of the second aspect of the present invention, the thin portion has a thickness approximately equal to the thickness of the ink inflow groove portion or an integral multiple of the thickness of the ink inflow groove portion. Since the inflow groove and the thin portion can be formed in the same process, the manufacturing process of the nozzle plate can be simplified, and the nozzle plate that can prevent the occurrence of ink leakage or the like due to poor bonding can be manufactured at low cost.

According to the nozzle plate of the third aspect of the present invention, since the thin portion is formed at a position deviating from the ridgeline position of the partition wall portion of the liquid chamber of the liquid chamber substrate, the thin portion and the liquid chamber are separated from each other. By preventing the occurrence of a step in the joint, it is possible to prevent the occurrence of ink turbulence and the pressure drop due to the sticking of air bubbles, and to prevent the ink ejection efficiency from being reduced or the ink ejection failure from occurring. Thus, the quality of a printed image can be improved.

[Brief description of the drawings]

FIG. 1 is a plan view of a nozzle portion of a nozzle plate to which an embodiment of a nozzle plate according to the present invention is applied.

FIG. 2 is a cross-sectional view of the nozzle plate of FIG.

FIG. 3 is a front sectional view showing a state in which a resist pattern for a nozzle hole is formed on a substrate and a first layer is formed by Ni electroforming on a substrate in a process of manufacturing the nozzle plate of FIG. 1;

FIG. 4 is a front sectional view showing a state in which a resist pattern for an ink inflow groove and a nozzle hole is formed on a first layer in FIG. 3 and a second layer is formed by Ni electroforming.

FIG. 5 is a cross-sectional view of a nozzle plate formed by peeling the substrate and the resist pattern of FIG. 4;

FIG. 6 is a schematic plan view showing a state where the nozzle plate and the liquid chamber substrate of FIG. 1 are joined.

FIG. 7 is a sectional view of the nozzle plate of FIG.

FIG. 8 is a front sectional view showing a state in which a resist pattern for nozzle holes is formed on a substrate and a first layer is formed by Ni electroforming on a substrate in a process of manufacturing a conventional nozzle plate.

9 is a front sectional view showing a state in which a resist pattern for an ink inflow groove and a nozzle hole is formed on the first layer in FIG. 8 and a second layer is formed by Ni electroforming.

FIG. 10 is a sectional view of a nozzle plate formed by peeling the substrate and the resist pattern of FIG. 9;

FIG. 11 is a plan view showing a thick part and a thin part of the nozzle plate of FIG. 10;

FIG. 12 is a schematic plan view showing a state where the nozzle plate and the liquid chamber substrate of FIG. 11 are joined.

13 is a cross-sectional view of the nozzle plate of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Nozzle plate 2 1st layer 3 2nd layer 4 Nozzle hole 5 Ink inflow groove 6 Thin part 7 Local thick part 20 Substrate 21, 22 Resist pattern 30 Liquid chamber 31 Liquid chamber substrate

Claims (3)

[Claims] An ink which is joined to a liquid chamber substrate on which a plurality of liquid chambers filled with ink are formed, and which supplies the ink to the liquid chambers and a plurality of nozzles respectively communicating with the respective liquid chambers. An inflow groove is formed, and ink in the liquid chamber is formed by a pressure change in the liquid chamber generated by a restoring force of a diaphragm formed in a part of each liquid chamber of the liquid chamber substrate and deformed by electrostatic force. A nozzle plate, characterized in that a thin portion having a predetermined thickness is formed in a portion other than a portion where the nozzle hole and the ink inflow groove are formed in the nozzle plate ejected from the nozzle plate. 2. The nozzle plate according to claim 1, wherein said thin portion has a thickness substantially equal to a thickness of said ink inflow groove portion or an integral multiple of a thickness of said ink inflow groove portion. . 3. The nozzle plate according to claim 1, wherein the thin portion is formed at a position deviated from a ridgeline position of a partition of the liquid chamber of the liquid chamber substrate.