JP7452281B2 - Liquid ejection head, ejection unit, liquid ejection device, bonded substrate - Google Patents

Description

The present invention relates to a liquid ejection head, an ejection unit, a device for ejecting liquid, and a bonded substrate.

For example, a liquid ejection head may include a first substrate provided with a pressure chamber communicating with a nozzle for ejecting liquid, a pressure generating means, and a terminal electrode communicating with the pressure generating means, and a channel for supplying liquid to the pressure chamber of the first substrate. Some use a bonded substrate (bonded substrate) that is bonded to a second substrate provided with.

Conventionally, a nozzle plate, a flow path substrate, a driving means, a diaphragm, and a holding substrate bonded to the side of the flow path substrate opposite to the nozzle plate are provided, and the holding substrate is connected to the driving means on the side of the flow path substrate. It is known to have a space surrounded by a holding substrate and a channel substrate at a position facing the holding substrate, and the space communicates with the atmosphere via a groove provided in the holding substrate (patent Reference 1).

Japanese Patent Application Publication No. 2013-158991

By the way, a protective film is formed on the flow path of the liquid ejection head to improve liquid resistance, but if the protective film is formed on the terminal electrode leading to the pressure generating means, the reliability of the electrical connection will decrease. There is a problem.

The present invention has been made in view of the above problems, and an object of the present invention is to improve the reliability of electrical connections.

In order to solve the above problems, a liquid ejection head according to the present invention includes:
pressure generating means for pressurizing a pressure chamber communicating with a nozzle that discharges liquid;
a first substrate including a terminal electrode connected to the pressure generating means;
a second substrate bonded to the first substrate and having a terminal electrode opening that exposes the terminal electrode;
The first substrate is provided with a through hole that penetrates the first substrate,
The second substrate is provided with a communication hole that communicates with the through hole of the first substrate,
The second substrate has an outside air communication path that communicates with the terminal electrode opening and the communication hole on the side opposite to the bonding surface with the first substrate,
The outside air communication path is provided at one of the four corners of the second substrate or at two diagonal corners.

According to the present invention, reliability of electrical connection can be improved.

FIG. 1 is an explanatory plan view of a bonded substrate that constitutes a liquid ejection head according to a first embodiment of the present invention. FIG. 2 is an explanatory plan view of a first substrate and a second substrate of the same bonded substrate. It is an explanatory view showing details of the outside air communication path portion of the second substrate as well. FIG. 6 is an explanatory diagram illustrating an outside air communication path and a gas intrusion detection chamber. FIG. 1 is an explanatory plan view of a bonded substrate that constitutes a liquid ejection head according to a first embodiment of the present invention. FIG. 3 is an explanatory diagram for explaining specific examples of each embodiment. FIG. 7 is an explanatory perspective view of the external appearance of a liquid ejection head according to a third embodiment of the present invention, viewed from the nozzle surface side. FIG. 4 is a perspective explanatory view of the external appearance seen from the side opposite to the nozzle surface. It is also an exploded perspective explanatory view. FIG. 4 is an exploded perspective view of the flow path forming member. 11 is an enlarged perspective explanatory view of the main part of FIG. 10. FIG. FIG. 4 is a cross-sectional perspective view of the flow path portion. FIG. 1 is a schematic explanatory diagram of an example of a device for discharging liquid according to the present invention. FIG. 2 is an explanatory plan view of an example of a head unit of the apparatus.

Embodiments of the present invention will be described below with reference to the accompanying drawings. A first embodiment of the present invention will be described with reference to FIGS. 1 to 3. FIG. 1 is an explanatory plan view of a bonded substrate that constitutes a liquid ejection head according to the same embodiment, and FIG. 2 is an explanatory plan view of a first substrate and a second substrate of the bonded substrate. FIG. 3 is an explanatory diagram showing details of the outside air communication passage portion of the second substrate, in which (a) is an explanatory plan view, and (b) is an explanatory cross-sectional view taken along line AA in (a).

The bonded substrate 200 is a substrate in which a first substrate 201 and a second substrate 202 are bonded (bonded) together using an adhesive or the like.

The first substrate 201 includes two rows of a plurality of piezoelectric elements 40, which are pressure generating means for pressurizing a pressure chamber communicating with a nozzle that discharges liquid. The piezoelectric element 40 includes a piezoelectric body 41, a lower electrode 42 as a common electrode, and an upper electrode 43 as an individual electrode, which sandwich the piezoelectric body 41 therebetween. A terminal electrode 44 connected to the upper electrode 43 is provided on the first substrate 201 .

The first substrate 201 is provided with openings 32 that serve as a plurality of supply ports for supplying liquid to a plurality of pressure chambers, respectively.

The first substrate 201 is provided with a base 28 to be bonded to the second substrate 202, and a through hole 29 passing through the first substrate 201 is provided in the bonding base 28.

The second substrate 202 is provided with a common supply channel 58 and a supply port 54 that communicates between the common supply channel 58 and the opening 32 of the first substrate 201 .

The second substrate 202 has an accommodating portion 251 that accommodates the piezoelectric element 40 of the first substrate 201, and a terminal opening 252 that exposes the terminal electrode 44 of the first substrate 201.

The second substrate 202 is provided with a communication hole 253 that communicates with the through hole 29 of the first substrate 201 . Further, the second substrate 202 has an outside air communication path 254 that communicates with the terminal opening 252 and the communication hole 253 on the side opposite to the bonding surface with the first substrate 201 .

Here, the outside air communication passage 254 is provided at one of the four corners of the second substrate 202. The four corners of the second substrate 202 are the four corners of a substantially rectangular region facing the terminal opening 252 in plan view. In other words, in this embodiment, it is a portion of the second substrate 202 that is lined up with the housing portions 251 at the end in the array direction of the plurality of housing portions 251 (the piezoelectric element array direction, the nozzle array direction).

As shown in FIG. 3A, the outside air communication passage 254 has a bellows-like pattern that is bent between the communication hole 253 and the terminal opening 252. When the cross-sectional area of the outside air communication passage 254 is S (see FIG. 3(b)) and the length is L, in this embodiment, L/S is set within the range of 0.50 to 20.00. There is.

A plurality of gas intrusion detection chambers 255 communicate with the outside air communication path 254 at predetermined intervals. The widths W1 and W2 of the gas intrusion detection chamber 255 are made larger than the width W3 of the outside air communication passage 254.

Next, the operation of this embodiment will be explained with reference to FIG. 4 as well. FIG. 4 is an explanatory diagram for explaining the case where multiple first and second substrates are produced.

The first substrate 201 is formed by forming a desired thin film using, for example, a 6-inch silicon substrate 203 using a CVD method, a sputtering method, a spin coating method, etc., and processing it using a photolithography method to form a large number of first substrates. 201 is produced and divided into individual first substrates 201. Regarding the second substrate 202, a large number of second substrates 202 are similarly produced on the Si substrate 200 and divided into individual second substrates 202.

Then, in a state where the first substrate 201 and the second substrate 202 are joined (pasted together), a liquid-resistant protective film is formed to protect the wall surface of the channel. In this case, in order to improve productivity, the protective film is formed by placing a plurality of bonded substrates (bonded substrates) 200 in a chamber of a protective film forming apparatus and performing batch processing.

In batch processing, a film is attached to the entire surface of the first substrate 201 and the second substrate 202, but the protective film is an insulating film, and if the protective film is attached to the terminal electrode 44, external connection cannot be established. Therefore, a protective film is formed while a protective tape cut out in the shape of the substrate is attached to the surface of the second substrate 202 opposite to the surface to be bonded to the first substrate 201.

As a result, a protective film is not formed on the terminal electrode 44, but a protective film can be formed on the common supply channel 58, the supply port 54, the opening 32, and the pressure chamber.

However, when attaching the protective tape to the second substrate 202, it is preferable to do so in a vacuum state in order to suppress inclusion of voids. When returning the pressure from vacuum to atmospheric pressure after pasting the protective tape, the part surrounded by the protective tape, second substrate 202, and first substrate 201 that does not penetrate through the second substrate 202 and first substrate 201 is placed in a vacuum state. Become.

In this embodiment, the terminal opening 252 is opened to the atmosphere in a vacuum state, but under atmospheric pressure, the protective tape of the terminal electrode 44 in a vacuum state is pushed toward the first substrate 201 and deforms greatly.

If this deformation of the protective tape causes the protective tape on the common supply flow path 58 and the terminal opening 252 to peel off, for example, when forming the protective film, the film forming gas may enter from the supply port 54 and the terminal electrode A protective film is formed on 44.

In addition, even if the protective tape can be transferred to the protective film formation process without peeling due to deformation of the protective tape under atmospheric pressure, a higher vacuum is required to form the protective film than when applying the protective tape. This may cause the terminal opening 252 to expand and the protective tape to peel off.

In order to solve this problem, it is conceivable to use a protective tape with high adhesive strength to suppress the deformation of the protective tape due to the pressure difference. However, protective tapes with high adhesive strength generate a lot of outgas under vacuum, which may deteriorate the film quality of the protective film and cause the adhesion strength of the protective film to decrease due to adhesion of outgas components to the substrate.

On the other hand, if a highly rigid protective tape is used to prevent deformation of the protective tape, it is not possible to achieve both suppression of deformation and heat resistance. Furthermore, if the thickness of the protective tape is increased in order to increase its rigidity, it becomes difficult to process the protective tape itself, causing problems such as air bubbles being easily trapped during application.

Therefore, in this embodiment, the terminal opening 252, which becomes evacuated after the protective tape is attached, communicates with the through hole 29 of the first substrate 201 through the outside air communication path 254 and the communication hole 253 of the second substrate 202.

Thereby, when the pressure is returned to atmospheric pressure, the terminal opening 252 also becomes atmospheric pressure via the through hole 29, the communication hole 253, and the outside air communication path 254, so that deformation of the protective tape can be suppressed. Furthermore, even if the terminal opening 252 expands in a high vacuum chamber when forming a protective film, the terminal opening 252 also becomes a high vacuum via the through hole 29, the communication hole 253, and the outside air communication path 254. Deformation of the protective tape can be suppressed.

Therefore, formation of a protective film on the terminal electrode is prevented, and the reliability of electrical connection is improved.

The shape, length, and depth of the outside air communication path 254 can be easily set, and can be appropriately set according to the material of the protective tape, the degree of vacuum at the time of applying the protective tape and forming the protective film, the vacuum release time, etc. do. Further, the length and depth of the outside air communication passage 254 are set so that the film forming gas does not enter through the through hole 253 as much as possible.

Next, the function of the gas intrusion detection chamber 255 communicating with the outside air communication path 254 will be explained.

After forming the protective film, it is necessary to check whether the film forming gas has entered the terminal opening 252 or not. To confirm the presence or absence of infiltration of the film-forming gas, analyze the components of the film-forming gas attached to the terminal electrode 44, perform a resistance test of the terminal electrode 44, and check whether the film-forming gas in the terminal electrode 44 or the communication flow path is present. It is possible to check for discoloration due to adhesion.

However, component analysis of the film-forming gas takes time. Resistance testing may generate foreign matter. It is difficult to determine whether the terminal electrode 44 has changed color because the amount of deposited film forming gas is very small. When checking for discoloration of the communication channel, it is impossible to confirm the presence or absence of discoloration because light is diffusely reflected depending on the width and depth of the communication channel.

Therefore, in this embodiment, the gas intrusion detection chamber 255 is communicated with the outside air communication path 254. The gas intrusion detection chamber 255 is made wider than the outside air communication passage 254 to suppress diffused reflection of light and to make it easy to see discoloration.

A plurality of gas intrusion detection chambers 255 are connected at predetermined intervals between the communication hole 253 of the outside air communication path 254 and the terminal opening 252.

Thereby, it is possible to confirm at which position in the outside air communication passage 254 the discoloration due to the intrusion of the film-forming gas is present, and it is possible to easily determine whether the film-forming gas has entered the terminal opening 252.

Next, a second embodiment of the present invention will be described with reference to FIG. 5. FIG. 5 is an explanatory plan view of a bonded substrate configuring the liquid ejection head according to the same embodiment.

In this embodiment, the outside air communication passages 254 are provided at two diagonal portions of the four corners of the second substrate 202, and each outside air communication passage 254 is communicated with the communication hole 253 and the terminal opening 252, respectively.

In this embodiment as well, the same effects as in the first embodiment can be obtained.

Next, a specific example regarding the intrusion of film-forming gas will be described with reference to FIG. 6. FIG. 6 is an explanatory diagram for explaining the specific example.

Here, 50 first substrates 201 were manufactured. On the other hand, regarding the second substrate 202, as described above, when the cross-sectional area of the outside air communication path 254 is S and the length of the flow path is L (see FIG. 3), L/S is changed as shown in FIG. Five second substrates 202 of each of the first and second embodiments were manufactured.

In Example 1, the outside air communication path 254 is the narrowest and longest, so it takes the longest time to communicate with the outside air, and during that time, the protective tape is likely to be deformed. It is a configuration that is difficult to get into.

On the other hand, Example 9 has a configuration in which deformation of the protective tape is least likely to occur, but film-forming gas easily enters.

The number of connections is the number of connections of the outside air communication passage 254 to the child opening 252. The number of connections "1" means that one outside air communication path 254 is arranged for one chip as in the first embodiment (Example 1-9). The number of connections "2" means that two outside air communication passages 254, 254 are arranged diagonally with respect to one chip as in the second embodiment, and the outside air communication passages 254 are arranged in each terminal opening 252. Yes (Example 10). In the configuration of the second embodiment (the number of connections is 2), the value of L/S describes the value of one outside air communication passage 254.

A preliminary evaluation revealed that the gas intrusion detection chamber 255 needs to have a size of 100 μm×100 μm (W1×W2 in FIG. 3).

Therefore, a gas intrusion detection chamber 255 with a size of 100 μm×100 μm was connected to the folded portion of the outside air communication path 254. The number of gas intrusion detection chambers 255 to be connected was appropriately set depending on the number of folded portions of the outside air communication path 254.

In order to confirm the effect of the outside air communication passage 254, five second substrates 202 of Comparative Example 1 without the outside air communication passage 254 were manufactured as comparison targets.

In each embodiment, one outside air communication path 254 is arranged per chip as shown in FIG. 1, or two outside air communication paths 254 are arranged as shown in FIG. 5, and the pattern shape of the outside air communication path 254 is a folded pattern. . Note that the shape can be appropriately set depending on process conditions such as desired tape attachment conditions and protective film formation conditions.

The number and locations of the outside air communication passages 254 are set to one at one of the four corners, or two positions diagonally to the four corners, thereby reducing the strength of the second substrate 202 due to the provision of the outside air communication passages 254. can be suppressed.

Further, in the embodiment, the communication hole 253 through which liquid does not pass is connected to the terminal opening 252, but there may be cases where it is not possible to provide the communication hole 253 through which liquid does not pass due to lack of room in the layout. In this case, if a step of sealing the outside air communication path 254 is provided in a later step, the same effect can be obtained even if the common supply flow path 58 in this embodiment is used as a communication hole and the terminal opening 252 is connected. can.

When the protective tape is attached, the terminal opening 252 does not become a closed space, and tape peeling due to tape deformation can be suppressed. A pattern may be formed on the surface to be bonded to the first substrate 201, but care must be taken not to cover it with adhesive or the like during bonding.

Next, a thin film of adhesive is transferred by flexographic printing onto the surface of the second substrate 202 on which the piezoelectric element housing portion 151 is formed, and the first substrate 201 and the second substrate 202 are pressed/heated using a wafer bonding device. They were bonded together to produce 50 laminated substrates.

Using the manufactured substrate, we checked whether the protective tape was deformed after pasting the protective tape, whether or not the film forming gas entered through the outside air communication path 254 after the protective film was formed, the connection resistance, and whether the substrate was damaged during flow. was evaluated.

Regarding the evaluation of the presence or absence of deformation of the protective tape, the terminal opening area was observed in detail using a microscope in order to detect minute deformations of the tape. If the protective tape was found to be even slightly deformed, the result was written as "slight deformation" in the protective tape deformation column of FIG.

The protective tape was attached under the conditions of 25° C. and 100 Pa, and the protective film was formed under the conditions of 120° C., 2 Pa, and 8 hours. The results are shown in FIG.

Regarding the five chips of Comparative Example 1 in which the outside air communication path 254 was not provided, all of the chips had deformation of the protective tape and infiltration of the film forming gas from the deformed part, and all of the chips were found to have poor connection resistance (NG). became.

On the other hand, regarding the board provided with the outside air communication passage 254, differences were observed depending on the L/S value.

Regarding Examples 5 to 7 with L/S values of 1.00 to 10.00, good quality was obtained, with no deformation of the protective tape, no infiltration of film forming gas, OK connection resistance, and no damage to the substrate. .

Regarding Example 8 with an L/S value of 0.50, there was no deformation of the protective tape, no damage to the board, and the connection resistance was OK, but a slight amount of film formation gas entered the terminal opening 252. .

Regarding Examples 4 and 3 with L/S values of 15.00 and 20.00, there was no intrusion of film forming gas, no damage to the substrate, and connection resistance was OK, but slight deformation of the protective tape was observed. Ta.

Regarding Example 9, in which the L/S value was 0.25, there was no deformation of the protective tape or damage to the board, but there was a slight intrusion of film forming gas into the terminal opening 252, and the connection resistance was not OK. However, it was near the upper limit of the standard.

Regarding Example 2 where the L/S value was 30.00, there was no intrusion of the film forming gas through the outside air communication path 254 and no damage to the substrate, but the protective tape was slightly deformed and the terminal opening was slightly Intrusion of the film forming gas into the portion 252 was observed. Although the connection resistance was OK, it was near the upper limit of the standard.

Regarding Example 1 with an L/S value of 50.00, there was no infiltration of the film forming gas through the outside air communication path 254 and no damage to the substrate, but the protective tape was slightly deformed and the terminal opening slightly Intrusion of the film forming gas into the portion 252 was observed. The connection resistance was OK, but compared to Example 2, it was OK just at the upper limit.

From the above, it can be seen that the desired connection resistance can be obtained by setting the value of L/S within the range of 0.50 to 20.00. Furthermore, it can be seen that by setting the value of L/S within the range of 1.00 to 10.00, the outside air communication passage 254 can be made with more margin. Furthermore, it can be seen that by setting the L/S value within the range of 0.25 to 10.00, it is possible to achieve a state in which even the slightest deformation of the protective tape is not observed even when observed with a microscope.

Further, by arranging the outside air communication passage 254 at one location or at two diagonal locations, no damage was observed on any of the substrates.

Next, a third embodiment of the present invention will be described with reference to FIGS. 7 to 12. FIG. 7 is an explanatory perspective view of the liquid ejection head according to the same embodiment as seen from the nozzle surface side, FIG. 8 is an explanatory perspective view of the external appearance as seen from the side opposite to the nozzle surface, and FIG. 9 is an exploded perspective explanatory view. 10 is an exploded perspective explanatory view of the flow path constituent members, FIG. 11 is an enlarged perspective view of the main part of FIG. 10, and FIG. 12 is a cross-sectional perspective view of the flow path portion.

The liquid ejection head 1 includes a nozzle plate 10, a channel plate (individual channel member) 20, a diaphragm member 30, a common channel tributary member 50, a damper member 60, a common channel main stream member 70, and a frame. It includes a member 80, a wiring member (flexible wiring board) 101 serving as a second board, and the like. A head driver (driver IC) 102 is mounted on the wiring member 101 . In this embodiment, the individual flow path member 20 and the diaphragm member 30 constitute an actuator substrate 2 that serves as a first substrate.

The nozzle plate 10 has a plurality of nozzles 11 that eject liquid. The plurality of nozzles 11 are arranged in a two-dimensional matrix.

The individual flow path member 20 includes a plurality of pressure chambers (individual liquid chambers) 21 each communicating with the plurality of nozzles 11 , a plurality of individual supply flow paths 22 communicating with the plurality of pressure chambers 21 , and a plurality of pressure chambers 21 . A plurality of individual recovery channels 23 are formed, each of which communicates with the other. One pressure chamber 21 and the individual supply flow path 22 and individual recovery flow path 23 communicating therewith are collectively referred to as an individual flow path 25.

The diaphragm member 30 forms a diaphragm 31 that is a deformable wall surface of the pressure chamber 21, and the diaphragm 31 is integrally provided with a piezoelectric element 40. Further, the diaphragm member 30 is formed with a supply side opening 32 communicating with the individual supply channel 22 and a recovery side opening 33 communicating with the individual recovery channel 23. The piezoelectric element 40 is a pressure generating means that deforms the diaphragm 31 and pressurizes the liquid in the pressure chamber 21.

Note that the individual flow path member 20 and the diaphragm member 30 are not limited to being separate members. For example, the individual flow path member 20 and the diaphragm member 30 can be integrally formed from the same member using an SOI (Silicon on Insulator) substrate. That is, an SOI substrate in which a silicon oxide film, a silicon layer, and a silicon oxide film are formed in this order on a silicon substrate is used, and the silicon substrate is used as the individual flow path member 20, and the silicon oxide film, the silicon layer, and the silicon oxide film are formed on the silicon substrate. The diaphragm 31 can be formed using the above. In this configuration, the layered structure of the silicon oxide film, the silicon layer, and the silicon oxide film of the SOI substrate becomes the diaphragm member 30. In this way, the diaphragm member 30 includes one made of a material formed into a film on the surface of the individual channel member 20.

The through hole 29A provided in the individual flow path member 20 and the through hole 29B provided in the diaphragm member 30 form a through hole 29 that penetrates the actuator substrate 2, which is the first substrate.

The common flow path tributary member 50 alternately connects a plurality of common supply flow path tributaries 52 communicating with two or more individual supply flow paths 22 and a plurality of common recovery flow path tributaries 53 communicating with two or more individual recovery flow paths 23. are formed adjacent to each other.

The common flow channel tributary member 50 includes a through hole that serves as a supply port 54 that communicates with the supply side opening 32 of the individual supply channel 22 and the common supply channel tributary 52, and a through hole that serves as a supply port 54 that communicates with the supply side opening 32 of the individual supply channel 22 and the common recovery channel 52. A through hole serving as a recovery port 55 through which the flow path tributary 53 passes is formed.

Further, the common flow path tributary member 50 includes a portion 56a of one or more common supply flow path main streams 56 that communicate with the plurality of common supply flow path tributaries 52, and one or more portions 56a of the common flow path main stream 56 that communicate with the plurality of common recovery flow path tributaries 53. It forms a part 57a of the main stream 57 of the common recovery channel.

The common channel tributary member 50 is a second substrate that is joined to the actuator substrate 2, which is the first substrate. The common channel tributary member 50 includes a housing portion 151 that accommodates the piezoelectric element 40 of the actuator substrate 2, and a terminal opening that exposes the terminal electrode (the terminal electrode 44 of the first embodiment) of the piezoelectric element 40 of the actuator substrate 2. 252.

In addition, the common channel tributary member 50 is provided with a communication hole 253 that communicates with the through hole 29 of the actuator board 2, and a terminal opening 252 and a communication hole 253 are provided on the side opposite to the joint surface with the actuator board 2. It has an outside air communication path 254 that communicates therewith.

The outside air communication path 254 has a bellows-like pattern that is bent between the communication hole 253 and the terminal opening 252, and the outside air communication path 254 has a plurality of gas intrusion detection chambers arranged at predetermined intervals. 255 are communicating.

The damper member 60 includes a supply side damper 62 that faces (opposes) the supply port 54 of the common supply channel tributary 52 and a recovery side damper 63 that faces (opposes) the recovery port 55 of the common recovery channel tributary 53. have.

Here, the common supply channel tributary 52 and the common recovery channel tributary 53 seal grooves arranged alternately in the common channel tributary member 50, which is the same member, with a damper member 60 forming a deformable wall surface. It consists of stopping.

The common flow path main flow member 70 forms a common supply flow path main flow 56 communicating with the plurality of common supply flow path tributaries 52 and a common recovery flow path main flow 57 communicating with the plurality of common recovery flow path tributaries 53 .

A part 56b of the main stream 56 of the supply channel and a part 57b of the main stream 57 of the common recovery channel are formed in the frame member 80. A portion 56b of the common main supply channel 56 communicates with a supply port 81 provided in the frame member 80, and a portion 57b of the common recovery channel main stream 57 communicates with a recovery port 82 provided in the frame member 80.

With this configuration, similarly to the first embodiment, formation of a protective film on the terminal electrode leading to the pressure generating means is prevented, and the reliability of the electrical connection is improved.

Next, an example of a device for discharging liquid according to the present invention will be described with reference to FIGS. 13 and 14. FIG. 13 is a schematic explanatory diagram of the apparatus, and FIG. 14 is a plan explanatory diagram of an example of the head unit of the apparatus.

The printing device 500, which is a device for discharging this liquid, includes a carrying means 501 that carries in a continuous body 510, and guides and conveys the continuous body 510, such as continuous paper or sheet material, carried in from the carrying means 501 to a printing means 505. A guide conveyance means 503, a printing means 505 that performs printing to form an image by discharging a liquid onto the continuous body 510, a drying means 507 that dries the continuous body 510, a delivery means 509 that carries out the continuous body 510, etc. It is equipped with

The continuous body 510 is sent out from the original winding roller 511 of the carry-in means 501, guided and conveyed by the rollers of the carry-in means 501, the guide conveyance means 503, the drying means 507, and the carry-out means 509, and then passed to the winding roller 591 of the carry-out means 509. It is wound up.

In the printing means 505, this continuous body 510 is conveyed on a conveyance guide member 559 facing a discharge unit 550 and a discharge unit 555, an image is formed by the liquid discharged from the discharge unit 550, and an image is formed by the liquid discharged from the discharge unit 555. Post-processing is performed with the processing liquid used.

Here, the ejection unit 550 includes, for example, full-line head arrays 551A, 551B, 551C, and 551D for four colors from the upstream side in the transport direction (hereinafter referred to as "head array 551" when the colors are not distinguished). is located.

Each head array 551 is a liquid ejecting means, and ejects black K, cyan C, magenta M, and yellow Y liquids to the conveyed continuous body 510, respectively. Note that the types and number of colors are not limited to these.

The head array 551 is, for example, an arrangement in which the liquid ejection heads (also simply referred to as "heads") 100 according to the present invention are arranged in a staggered manner on the base member 552, but is not limited thereto.

Note that in the above embodiment, an example is described in which the bonded substrate is a component of the liquid ejection head, but the present invention is not limited to this. That is, in a bonded substrate in which a first substrate including a terminal electrode and a second substrate having a terminal electrode opening that exposes the terminal electrode of the first substrate are bonded, the first substrate has a hole that penetrates the first substrate. A through hole is provided in the second substrate, a communication hole communicating with the through hole in the first substrate is provided in the second substrate, and a terminal electrode opening and It has an outside air communication path that communicates with the communication hole, and the outside air communication path is provided at one of the four corners of the second substrate or at two diagonal corners.

Examples of such a bonded substrate include a semiconductor substrate.

Thereby, reliability of electrical connection can be improved.

In the present application, the liquid to be ejected may have a viscosity and surface tension that can be ejected from the head, and is not particularly limited, but the viscosity becomes 30 mPa・s or less at room temperature and normal pressure, or by heating or cooling. Preferably. More specifically, solvents such as water and organic solvents, coloring agents such as dyes and pigments, functional materials such as polymerizable compounds, resins, and surfactants, and biocompatible materials such as DNA, amino acids, proteins, and calcium. , edible materials such as natural pigments, etc., and these include, for example, inkjet inks, surface treatment liquids, constituent elements of electronic devices and light emitting devices, and formation of electronic circuit resist patterns. It can be used for purposes such as a liquid for use in liquids, a material liquid for three-dimensional modeling, and the like.

As an energy generation source (pressure generation means) for discharging liquid, piezoelectric actuators (laminated piezoelectric elements and thin film piezoelectric elements), thermal actuators using electrothermal conversion elements such as heating resistors, and static actuators consisting of a diaphragm and opposing electrodes are used. This includes those that use electric actuators.

The "ejection unit" is a liquid ejection head with functional parts and mechanisms integrated, and includes an assembly of parts related to liquid ejection. For example, the "discharge unit" includes a combination of a head tank, a carriage, a supply mechanism, a maintenance recovery mechanism, a main scanning movement mechanism, a liquid circulation device, and a liquid discharge head.

Here, integration refers to, for example, a liquid ejection head, a functional component, or a mechanism fixed to each other by fastening, adhesion, engagement, etc., or one in which one is held movably relative to the other. include. Further, the liquid ejection head, the functional parts, and the mechanism may be configured to be detachable from each other.

For example, some discharge units have a liquid discharge head and a head tank integrated. In addition, there are devices in which a liquid ejection head and a head tank are integrated by being connected to each other with a tube or the like. Here, a unit including a filter may be added between the head tank and the liquid ejection head of these ejection units.

Further, some ejection units have a liquid ejection head and a carriage integrated.

Further, some ejection units have the liquid ejection head movably held by a guide member that constitutes a part of the scanning movement mechanism, so that the liquid ejection head and the scanning movement mechanism are integrated. Further, there are some in which the liquid ejection head, the carriage, and the main scanning movement mechanism are integrated.

Further, some ejection units have a cap member, which is part of the maintenance and recovery mechanism, fixed to a carriage to which the liquid ejection head is attached, so that the liquid ejection head, the carriage, and the maintenance and recovery mechanism are integrated.

Further, some discharge units have a tube connected to a liquid discharge head to which a head tank or a flow path component is attached, so that the liquid discharge head and a supply mechanism are integrated. The liquid from the liquid storage source is supplied to the liquid ejection head through this tube.

It is assumed that the main scanning movement mechanism also includes a single guide member. Furthermore, the supply mechanism includes a single tube and a single loading section.

Note that although the "discharge unit" is described here in combination with a liquid discharge head, the "discharge unit" includes a head module including the liquid discharge head described above, a head unit, functional parts such as those described above, It also includes those with integrated mechanisms.

The "device for discharging liquid" includes a device that includes a liquid discharging head, a discharging unit, a head module, a head unit, etc., and drives the liquid discharging head to discharge liquid. Devices that eject liquid include not only devices that can eject liquid onto objects to which liquid can adhere, but also devices that eject liquid into the air or into liquid.

This "device for discharging liquid" can include means for feeding, transporting, and discharging objects to which liquid can adhere, as well as pre-processing devices, post-processing devices, and the like.

For example, an image forming device is a device that ejects ink to form an image on paper as a “device that ejects liquid,” and an image forming device that forms layers of powder to form three-dimensional objects (three-dimensional objects). There is a three-dimensional modeling device (three-dimensional modeling device) that discharges a modeling liquid onto a powder layer.

Further, the "device for ejecting liquid" is not limited to a device that can visualize significant images such as characters and figures using ejected liquid. For example, it includes those that form patterns that have no meaning in themselves, and those that form three-dimensional images.

The above-mentioned "something to which a liquid can adhere" refers to something to which a liquid can adhere at least temporarily, such as something that adheres and sticks, something that adheres and penetrates. Specific examples include recording media such as paper, recording paper, recording paper, film, cloth, electronic boards, electronic components such as piezoelectric elements, powder layers, organ models, test cells, etc. Unless otherwise specified, it includes everything to which liquid can adhere.

The material for the above-mentioned "material to which liquid can adhere" may be paper, thread, fiber, fabric, leather, metal, plastic, glass, wood, ceramics, etc., as long as liquid can adhere thereto, even temporarily.

Further, the term "device for discharging liquid" includes a device in which a liquid discharging head and an object to which liquid can be attached move relative to each other, but the present invention is not limited to this. Specific examples include a serial type device that moves a liquid ejection head, a line type device that does not move a liquid ejection head, and the like.

In addition, the "device for discharging a liquid" includes a processing liquid coating device that discharges a processing liquid onto paper in order to apply the processing liquid to the surface of the paper for the purpose of modifying the surface of the paper, etc. There is an injection granulation device that granulates fine particles of the raw material by spraying a composition liquid in which the raw material is dispersed through a nozzle.

In addition, in the terms of this application, image formation, recording, printing, imprinting, printing, modeling, etc. are all synonymous.

1 Liquid ejection head 2 Actuator board (first board)
10 Nozzle plate 11 Nozzle 20 Individual channel member 21 Pressure chamber 22 Individual supply channel 23 Individual recovery channel 30 Vibration plate member 40 Piezoelectric element 50 Common channel member 52 Common supply channel tributary 53 Common recovery channel tributary 56 Common supply Main stream channel 57 Main stream common recovery channel 101 Wiring member (second board)
201 First substrate 202 Second substrate 203 Anisotropic conductive film 212 Wiring electrode 213 First insulating film 214 Second insulating film 222 Wiring electrode 500 Printing device (device for discharging liquid)
550 Discharge unit

Claims (9)

pressure generating means for pressurizing a pressure chamber communicating with a nozzle that discharges liquid;
a first substrate including a terminal electrode connected to the pressure generating means;
a second substrate bonded to the first substrate and having a terminal electrode opening that exposes the terminal electrode;
The first substrate is provided with a through hole that penetrates the first substrate,
The second substrate is provided with a communication hole that communicates with the through hole of the first substrate,
The second substrate has an outside air communication path that communicates with the terminal electrode opening and the communication hole on the side opposite to the bonding surface with the first substrate,
The liquid ejection head is characterized in that the outside air communication passage is provided at one of the four corners of the second substrate or at two diagonal corners. The liquid ejection head according to claim 1, wherein the outside air communication passage has a L/S of 0.50 to 20.00, where S is a cross-sectional area and L is a length. . The liquid ejection head according to claim 1, wherein the outside air communication passage has a L/S in a range of 1.00 to 10.00, where S is a cross-sectional area and L is a length. . 4. The liquid ejection head according to claim 1, wherein the through hole of the first substrate is independent of the liquid flow path. 5. The liquid ejection head according to claim 1, wherein a gas intrusion detection chamber having a width equal to or larger than the width of the outside air communication path communicates with the outside air communication path of the second substrate. 6. The liquid ejection head according to claim 5, wherein a plurality of the gas intrusion detection chambers are arranged at predetermined intervals. A discharge unit comprising the liquid discharge head according to any one of claims 1 to 6. An apparatus for ejecting liquid, comprising the liquid ejection head according to claim 1 or the ejection unit according to claim 7. a first substrate including a terminal electrode;
a second substrate bonded to the first substrate and having a terminal electrode opening that exposes the terminal electrode;
The first substrate is provided with a through hole that penetrates the first substrate,
The second substrate is provided with a communication hole that communicates with the through hole of the first substrate,
The second substrate has an outside air communication path that communicates with the terminal electrode opening and the communication hole on the side opposite to the bonding surface with the first substrate,
The bonded substrate is characterized in that the outside air communication path is provided at one of the four corners of the second substrate or at two diagonal corners.

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