JP3154835B2 - Method of manufacturing inkjet head - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing an ink-jet head for performing recording by discharging ink droplets.

In an ink jet head, since the ink in a pressure chamber is ejected from a nozzle, it is necessary to form the nozzle diameter uniformly so that the size of the ink droplet does not vary.

[0003]

2. Description of the Related Art Conventionally, in order to form a nozzle, for example, as shown in FIG.
Then, a wet anisotropic etching process was performed from both sides, and the through-hole was used as the nozzle 52.

[0004]

The speed of the etching process is greatly affected by the temperature of the etching solution. Therefore, it is desirable that the temperature of the etching liquid is always a predetermined constant temperature during the etching process. However, since the above-described processing of the hole of the nozzle requires a processing time of several hours, it is inevitable that the temperature of the etching solution fluctuates during the processing.

As a result, the ratio of the depth of the etching process from both surfaces to the single crystal silicon wafer 51 varies, the nozzle diameter varies, and the size of the ink droplet varies depending on the nozzle, thereby deteriorating the recording quality. Was causing it.

Further, when the thickness of the single-crystal silicon wafer 51 varies, the nozzle diameter varies due to the same phenomenon, and the size of the ink droplet varies, thereby deteriorating the recording quality.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a method for manufacturing an ink jet head capable of forming the diameter of a nozzle hole uniformly and accurately.

[0008]

In order to achieve the above object, a method of manufacturing an ink jet head according to the present invention, as shown in FIG. A concave portion 2 having a predetermined shape and size is formed from the surface by anisotropic etching to form a nozzle plate 3, and a pressure chamber 5 for applying a discharge pressure to ink is formed in a concave shape by communicating with an ink supply path 6. To form a flow path plate 4 and join the nozzle plate 3 and the flow path plate 4 with the surface on which the recess 2 is formed and the surface on which the pressure chamber 5 is formed facing each other. After that, the nozzle plate 3 is ground from the surface opposite to the joining surface to a thickness at which the concave portion 2 opens as the nozzle hole 7 with a predetermined diameter.

Further, in the method of manufacturing an ink jet head according to the present invention, after a single crystal silicon wafer 1 is ground to a predetermined thickness, a predetermined shape is formed from one surface of the single crystal silicon wafer 1 by anisotropic etching. The nozzle plate 3 is formed by forming a nozzle hole 7 having dimensions, and a pressure chamber 5 for applying a discharge pressure to the ink is formed in a concave shape in communication with the ink supply path 6 to form the flow path plate 4. The nozzle plate 3 is joined to the surface of the flow path plate 4 on the side where the pressure chamber 5 is formed.

[0010]

By grinding the single crystal silicon wafer 1 to reduce the thickness, the etching process can be performed from one side having a short processing time, and variations in the etching process can be suppressed. At the same time, the variation in the thickness of the single-crystal silicon wafer 1 is eliminated by the grinding, and the thickness can be made uniform.

[0011]

An embodiment will be described with reference to the drawings. 1 to 6 show a method of manufacturing an ink jet head according to a first embodiment of the present invention and its manufacturing steps.

Here, first, the thickness is, for example, 525 μm ±
On one surface side of a 25 μm single crystal silicon wafer 1,
A portion other than the portion where the nozzle hole is formed is covered with a resist to form a nozzle hole pattern having a predetermined shape and size, and anisotropic etching is performed from the surface side.

Then, as shown in FIG. 2, on one surface side of the single crystal silicon wafer 1, a concave portion 2 whose surface opening conforms to the nozzle hole pattern is formed, for example, at an etching angle of 55 ° and a single crystal silicon wafer. It is formed so as to be depressed to an intermediate portion having a thickness of 1.

Thus, the single-crystal silicon wafer 1
Is formed, and then a flow path plate 4 is joined to the nozzle plate 3 as shown in FIG. Channel plate 4
The material is a single-crystal silicon wafer in this case, and a pressure chamber 5 for applying a discharge pressure to ink is formed in a concave shape in advance by anisotropic etching from one surface side, communicating with an ink supply path 6. Keep it.

The surface of the nozzle plate 3 on the side where the recess 2 is formed, the pressure chamber 5 of the flow path plate 4 and the ink supply path 6
Are aligned and directly joined without using an adhesive. Direct bonding is for example 110
This is done by heating at 0 ° C. for 30 minutes.

Next, as shown in FIG.
Is ground from the surface side opposite to the joining surface to a thickness such that the concave portion 2 opens as a nozzle hole 7 having a predetermined diameter. The grinding amount is
For example, when the surface opening of the concave portion 2 is a square having a side of 200 μm and the diameter (one side) of the nozzle hole 7 is set to 50 μm, the grinding may be performed so that a thickness of about 106 μm remains.

After the nozzle plate 3 has been ground in this way and a nozzle hole 7 having a predetermined diameter is opened in the nozzle plate 3,
As shown in FIG. 4, a piezoelectric element 8 is bonded to the surface of the flow path plate 4 located on the back side of the pressure chamber 5.

Although only two nozzle holes 7 are enlarged and shown in FIGS. 1 to 4, as shown in FIG. 5, one single-crystal silicon wafer 1 has a large number of ink jets. As shown in FIG. 6 showing a portion A of one of the ink jet heads 10, each ink jet head 1
A large number of nozzle holes 7 are formed at zero.

Therefore, after bonding the piezoelectric element 8 to the flow path plate 4, the whole is cut and divided for each ink jet head 10 as shown in FIG. The ink-jet head 10 thus formed is deformed by applying a voltage to the piezoelectric element 8, whereby pressure is applied to the ink in the pressure chamber 5, and the ink becomes an ink droplet from the nozzle hole 7. Discharged.

FIGS. 7 to 10 show a second embodiment of the present invention. As shown in FIG. 7, before a hole is formed in a single crystal silicon wafer 1 for forming a nozzle plate 3. A single-crystal silicon wafer 1 to a predetermined thickness (for example, 10
6 μm).

Here, after the grinding, as shown in FIG. 8, a recess 2 is formed in the single crystal silicon wafer 1 by anisotropic etching to obtain a nozzle hole 7 of a predetermined size. This is referred to as a nozzle plate 3.

Then, as shown in FIG. 9, the flow path plate 4 is directly joined to the nozzle plate 3 and, as in the first embodiment, as shown in FIG. After the piezoelectric element 8 is joined to the inkjet head 10, the substrate is cut and divided into one inkjet head 10 shown in FIG.

When an ink jet head is manufactured as in the second embodiment, the same ink jet head as in the first embodiment can be obtained.

[0024]

According to the method of manufacturing an ink jet head of the present invention, only one side of the etching process needs to be performed to form the nozzle hole. Since the nozzle plate is obtained by grinding the crystalline silicon wafer, variations in the thickness of the nozzle plate are eliminated, and a uniform thickness is obtained. As a result, the nozzle holes are formed to a uniform and accurate size without variation in the diameter by etching. can do.

[Brief description of the drawings]

FIG. 1 is a front partial sectional view showing a manufacturing process of a first embodiment.

FIG. 2 is a partial front sectional view showing a manufacturing process of the first embodiment.

FIG. 3 is a partial front sectional view showing a manufacturing process of the first embodiment.

FIG. 4 is a partial front sectional view of the ink jet head according to the first embodiment.

FIG. 5 is an overall plan view showing the manufacturing process of the first embodiment.

FIG. 6 is a plan view showing the manufacturing process of the first embodiment.

FIG. 7 is a partial front sectional view showing a manufacturing process of the second embodiment.

FIG. 8 is a partial front sectional view showing a manufacturing process of the second embodiment.

FIG. 9 is a partial front sectional view showing a manufacturing process of the second embodiment.

FIG. 10 is a front partial sectional view of a conventional nozzle plate.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Single crystal silicon wafer 2 Depression 3 Nozzle plate 4 Flow path plate 5 Pressure chamber 6 Ink supply path 7 Nozzle hole

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-4-31054 (JP, A) JP-A-3-2977653 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B41J 2/135 B41J 2/16 B41J 2/045

Claims (1)

(57) [Claims] 1. A nozzle plate is formed by forming a recess having a predetermined shape and size from one surface of a single crystal silicon wafer by anisotropic etching, and a pressure chamber for applying a discharge pressure to ink is provided in an ink supply path. The nozzle plate and the flow channel plate face each other on the side on which the concave portion is formed and the surface on the side on which the pressure chamber is formed. A method for manufacturing an ink jet head, comprising: after joining together, grinding the nozzle plate from the surface opposite to the joining surface to a thickness such that the recess has a predetermined diameter and opens as a nozzle hole.