JPH0664178A - Manufacture of ink jet head - Google Patents

Abstract

PURPOSE:To supply ink steadily and to improve thereby ejection characteristing of ink by a method wherein shallow and deep parts of an ink passage having varied depth are made continuous by connection with gentle slopes, and thereby swallowing of bubbles is eliminated. CONSTITUTION:An ink passage formed over a glass substrate 1 is formed of parts in different depths, and pressure chamber 1f equipped with a piezoelectric element 5 for pressurizing the ink inside the passage and a nozzle 1e for ejecting the ink are provided in the shallow parts in the passage, and those parts are made continuous with a deep part 1a of the passage by connection with gentle sloped passages 1d. A vibration plate 4 is bonded to the surface on the ink passage side of the passage substrate 1 to seal up the ink passage. In manufacturing the ink passage, the deep part 1a of the passage is formed first by means of etching, then the sloped passages 1d are formed by grinding with sandblast applied to the stepped parts of the deep part and each one end of the shallow parts adjoining the deep part. Then, the shallow parts 1e and 1f of the passage are formed subsequently by etching.

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.

[0002]

2. Description of the Related Art Conventionally, a plurality of ink channels are provided on one channel substrate, and each ink channel has a nozzle,
A so-called on-demand type multi-nozzle jet in which a pressurizing chamber is arranged in a plane, and an ink ejecting means such as a piezoelectric element is provided facing the pressurizing chamber on a vibration plate bonded to the flow path substrate. I have a head. In this jet head, glass is used as a flow path substrate in order to improve the sealing property of the ink flow path, and a groove to be a flow path is formed by etching. In the ink flow path, for example, Japanese Patent Publication No. 59-261
As disclosed in Japanese Patent Publication No. 9, a nozzle, a pressurizing chamber, a restricting portion which is a connecting portion between an ink reservoir and an ink flow path, and the like are formed shallower than other flow path portions to change acoustic resistance and inertance. In some cases, this improves the ink ejection characteristics.

[0003]

As described above, when the ink flow path including the portions having different depths is formed by etching, it is necessary to perform the etching in two steps, and the etching is performed between the shallow portion and the deep portion. A steep step is created.
For this reason, after ejecting the ink, air bubbles are likely to be entrained when the meniscus retreats, and it is difficult to obtain stable ink ejection. There is also a problem that bubbles remain in the ink flow path and it is difficult to supply ink.

Therefore, an object of the present invention is to make a shallow portion and a deep portion of an ink flow path including portions having different depths continuous with a gradual inclination to prevent entrainment of air bubbles and enable stable ink supply. Another object of the present invention is to provide a method for manufacturing an inkjet head that achieves improved ink ejection characteristics.

[0005]

In order to achieve the above object, in the present invention, an ink flow path including a pressurizing chamber having a pressurizing means for pressurizing internal ink and a nozzle for ejecting the ink is formed. In a method of manufacturing an inkjet head including a glass flow channel substrate and a vibrating plate bonded to a surface of the flow channel substrate on the ink flow channel side, the ink flow channels have different depths. Including the part, at the time of manufacturing, first form the flow path of the deep part by etching,
Next, the step portion of the flow channel in the deep portion and a part of the flow channel in the shallow portion adjacent thereto are ground by sandblasting to form an inclined flow passage, and finally an ink containing the shallow portion and the deep portion. It is characterized in that the entire flow path is formed by etching.

[0006]

EXAMPLE An example of the present invention will be described. In the manufacturing method of the present invention, as a first step, a step of forming a flow channel in a deep portion by etching, as a second step, a step portion of the flow channel in the deep portion, and a part of the flow channel in a shallow portion adjacent thereto And sand-blasting to form an inclined channel, and as a third step, a step of forming the entire ink channel including a shallow portion and a deep portion by etching.

First, in the first step, (1), a photosensitive resist is uniformly applied on the upper surface of a glass flow path substrate.
(2) The other part except the pattern part, which is the deep part of the flow path, is exposed and cured so that the exposed part is not removed by the developing solution. (3) The photosensitive resist in the unexposed portion, that is, the pattern portion in the deep portion of the channel is removed by development. (4) The portion from which the photosensitive resist has been removed is etched with a hydrofluoric acid solution to form a channel in a deep portion.
(5) The photosensitive resist in the cured exposed portion is removed. Through this first step, as shown in FIG.
The flow path 1a in a deep portion can be formed on the upper surface of the. At the time of this etching, the corners of the flow passage 1a in the deep portion are sharp step portions 1
It is b.

Then, in the second step (1), as shown in FIG. 2, the flow of the stepped portion 1b of the flow channel 1a and the flow of a shallow portion adjacent to the stepped portion 1b such as a nozzle, a pressurizing chamber or a restriction portion. The photosensitive resist 2 is applied as a masking member to the other part, leaving part of the path 1c. (2), the photosensitive resist 2 is exposed and cured. (3) As shown in FIG. 3, alumina or the like is sprayed onto the step portion 1b and the part 1c of the flow path, and the sandblasting 3 is performed. As a result, the steep step becomes the gently inclined flow path 1d. (4),
The photosensitive resist 2 is removed.

Then, in the third step, as in the first step,
(1) A photosensitive resist is uniformly applied on the upper surface of the flow path substrate, and (2) the other part except the pattern part which is the entire ink flow path including the shallow part and the deep part is exposed and exposed. The part is cured, and (3), the photosensitive resist of the unexposed part, that is, the pattern part of the entire ink channel is removed by development
(4) The portion where the photosensitive resist is removed is etched with a hydrofluoric acid solution to form the entire ink flow path, and (5) the photosensitive resist in the cured exposed portion is removed.

As a result of this step, as shown in FIG. 4, the flow path substrate 1 has a deep flow path 1a and a shallow flow path, for example, the nozzle 1e and the pressurizing chamber 1f. An ink flow path including the inclined flow path 1d and the restricting portion 1g connected to the pressurizing chamber 1f can be formed. Therefore, the vibration plate 4 is joined to the surface of the flow path substrate 1 on the ink flow path side by heat welding or the like to seal the ink flow path, and the piezoelectric element, which is a pressing means, is provided on the outer surface of the vibration plate facing the pressurizing chamber 1f. 5 is attached with a conductive adhesive or the like to complete the production.

When a drive signal is supplied from a drive circuit (not shown) to the electrodes on both sides of the piezoelectric element 5 when ejecting ink, the piezoelectric element 5 is curved inwardly of the pressurizing chamber 1f and the pressurizing chamber 1f.
Compress the volume of. For this reason, the ink is pressurized, the ink flows toward the nozzle 1e through the inclined channel 1d, the deep channel 1a and the inclined channel 1d, and is ejected from the nozzle 1e to the outside for printing. After the ink is ejected, the voltage applied to the piezoelectric element 5 becomes 0, and the piezoelectric element 5 bends outward due to the reaction and the pressure in the pressurizing chamber 1f becomes negative. Even when the meniscus of the nozzle 1e retreats due to this negative pressure and the ink tries to return toward the pressure chamber 1f, the inclined flow passage 1d
Since it is gentle, bubbles do not get caught in the ink. At the same time, the ink in the ink storage chamber (not shown) is supplied to the pressure chamber 1f via the restricting portion 1g, and similarly, the ink is smoothly supplied to the nozzle 1e to restore the meniscus to the original state.

[0012]

As described above, according to the present invention, there is a step of forming an inclined flow path by sandblasting between a step of forming a flow path in a deep portion and a step of forming a flow path in a shallow portion. In the formed ink flow path, the continuity between the portions having different depths becomes a gentle slope, and air bubbles are not entrained during ink movement. Further, since stable ink supply can be obtained, highly accurate and stable ink ejection characteristics can be realized.

[Brief description of drawings]

FIG. 1 is a sectional view of an essential part showing a state in which a deep portion is formed in a manufacturing method of the present invention.

FIG. 2 is a plan view showing a state in which a predetermined portion is left and masked on the upper surface of a flow path substrate having a deep portion formed therein.

FIG. 3 is a cross-sectional view showing a state in which a predetermined portion of FIG. 2 is ground by sandblasting.

FIG. 4 is a partially cutaway enlarged sectional view of an inkjet head manufactured by the manufacturing method of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Flow path substrate 1a Deep flow path 1b Step part 1c Shallow flow path part 1d Inclined flow path 1e, 1f, 1g Shallow flow path (nozzle, pressure chamber,
Restriction part) 4 Vibration plate 5 Pressurizing means (piezoelectric element)

Claims (1)

[Claims] 1. A glass flow path substrate having an ink flow path including a pressurizing chamber having a pressurizing means for pressurizing ink inside, and a nozzle for ejecting the ink, and the flow path substrate. In a method for manufacturing an inkjet head including a vibrating plate joined to a surface on the ink flow path side, the ink flow path includes portions having different depths, first, the flow path of the deep portion is formed by etching, The step portion of the flow passage in the deep portion and a part of the flow passage in the shallow portion adjacent thereto are ground by sandblasting to form an inclined flow passage, and finally the ink flow including the shallow portion and the deep portion. A method for manufacturing an inkjet head, wherein the entire path is formed by etching.