JPH09323419A - Ink jet head and ink jet recording apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable high-grade recording by preventing the emission trouble of ink caused by air bubbles in a liquid chamber. SOLUTION: An ink jet head is constituted by bonding a top plate 20 having a plurality of ink emitting orifices 21, a common liquid chamber 23 and an ink supply cylinder 24 communicating with an opening part 25 to an electrothermal converter 11 and a substrate 10 having a pad connecting wiring 42 to the electrothermal converter 11 provided to the rear end part thereof. In this case, the inner surface of a supply soln. chamber 23 is inclined in an anti-emitting direction from the ink emitting orifices 21 to the opening part 25 to make it possible to allow ink air bubbles ready to stagnate on the inner surface of the common liquid chamber 23 to escape.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet head used in an ink jet recording apparatus for ejecting a recording liquid (ink or the like) as ejection droplets from an ejection port (orifice) and adhering it to a recording medium for recording. , And an inkjet recording apparatus including an inkjet head.

[0002]

2. Description of the Related Art Conventionally, in an ink jet head, an electrothermal converter formed on a substrate as described in JP-A-55-132253, a recording ink ejection port on the substrate, It is configured by joining an ink flow path having a heat acting portion by an electrothermal converter and a top plate having a common liquid chamber for supplying ink to the ink flow path.

Further, in the ink jet head,
A drive circuit for driving the electrothermal converter arranged on the substrate is built in the substrate. A wiring board for drawing out wiring from the drive circuit of the board is provided, and the board and the wiring board are arranged adjacent to each other on the holding member.

The above ink jet head will be further described with reference to FIGS.

FIG. 6 is a schematic perspective view of an ink jet head having the above-mentioned structure.

FIG. 7 is a sectional view showing an outline of the AA section of FIG. FIG. 8 is a partial sectional view showing details of the nozzle portion shown in FIG. 7.

In FIG. 7, reference numeral 112 is a substrate on which a plurality of ink ejection generating means, for example, electrothermal conversion elements are arranged. Reference numeral 113 denotes a top plate, which has a plurality of ink ejection ports 101,
A nozzle portion 102 that serves as an ink passage communicating with the ink ejection port 101, a nozzle wall portion 103 that serves as an ink passage wall, a common liquid chamber 104 that supplies ink to each nozzle portion 102, and an ink from the ink supply cylinder 116 to the common liquid chamber 104. Is a top plate integrally formed with an opening 105 on the upper surface of the liquid chamber for supplying liquid and a liquid chamber frame 106 that is a joint with the substrate 112. Further, 119 is a flat portion of the upper surface of the common liquid chamber 104. Further, 111 is a metal supporting member for constructing and configuring each component.

Reference numeral 150 shown in FIG. 8 denotes a joint surface between the upper surface wall 155 of the common liquid chamber 104 and the rear end portion 151 of the nozzle portion 102. A plurality of ink ejection ports 101 are provided in the ejection direction of the nozzle portion 102. Further, the top plate 113 is formed on the substrate 112, and the electrothermal conversion element 158 is arranged on the substrate 112.

Further, as shown in FIG. 6, the metal supporting member 1
A wiring board 110 is arranged on the wiring board 11, and is connected to the board 112 by bonding wires 109. The bonding wire 109 is for electrically connecting the pad 107 on the substrate 112 and the pad 108 on the wiring substrate 110.

In this structure, the flow of ink supply at the time of ink ejection will be described. For example, the ink flows out from a tank (not shown) for storing ink, the ink passes through various connecting pipes, etc. Of the common liquid chamber 10 through the opening 105 on the upper surface of the liquid chamber.
It is temporarily stored in 4. Further, each nozzle unit 10
The ink also flows to 2 and is held at the tip of the ejection port 101 by surface tension or the like. Here, the ejection signal is sent to the substrate 11
When applied to the second electrothermal converter 158, air bubbles are generated in the ink in the nozzle portion 102 correspondingly, and the droplets fly from the ink ejection ports 101 by the action thereof.

Therefore, when the ejection of the nozzle portion 102 is started, it is necessary to sequentially receive the supply of ink necessary for the ejection from the common liquid chamber 104 side.

At this time, if the bubble 300 exists in the common liquid chamber 104 for some reason as shown in FIG. 7, the ink supply to the nozzle portion 102 is temporarily interrupted, and the ink ejection becomes unstable. The print quality deteriorates. Further, if this state continues, ink will not be ejected and printing will be impossible.

The above-described generation of bubbles may occur during printing or may occur before starting printing.
If it occurs during printing, the user of the ink jet recording apparatus or the like performs a recovery operation by means such as capping to remove bubbles in the liquid chamber. If air bubbles have already been generated before printing starts,
Before the ink ejection is started, the above recovery operation is automatically performed to remove the bubbles in the liquid chamber.

Here, in particular, bubbles 298 generated during printing.
In FIG. 8, the ejection signal is applied to the electrothermal converter 158 of the substrate 112 in FIG. 7, bubbles are generated in the ink in the nozzle portion 102 corresponding to this, and the action causes each of the droplets to be an ink ejection port. When flying from 101, air bubbles acting in the opposite direction pass through the nozzle rear end portion 151 and pass through the common liquid chamber 104.
Stays on the joint surface 150 between the upper wall 155 and the rear end portion 151 of the nozzle portion 102.

These fine bubbles 298 bond with each other to form larger bubbles 300 (FIG. 7) and grow.

On the other hand, when these fine bubbles 298 flow back into the nozzle portion 102 during printing, as described above,
The ink supply to the nozzle portion 102 is temporarily interrupted, the ink ejection becomes unstable, and the printing quality is degraded.

Regarding the ink jet head in a storage state (non-printing state) for a long term, the above-mentioned bubble 300 (298) grows due to gas permeation from the outside, invasion of air from the discharge port, and the like. It may be in a state of staying in the flat portion 119 on the upper surface of the chamber 104 (299 in FIG. 7). In this case, the bubbles 299 accumulated in the flat portion of the upper surface of the common liquid chamber cannot be removed by the recovery operation, and also deteriorate the wettability of the ink in the nozzle, the liquid chamber, or the like.
This is one of the causes of lowering the print quality during ejection.

Therefore, at the time of long-term storage, the storage time is stored in the main body of the apparatus, and the recovery operation is automatically performed at regular intervals to remove bubbles 299 in the liquid chamber and prevent growth. There is.

[0019]

However, in the above-mentioned conventional example, since there is the flat portion 119 on the upper surface of the liquid chamber, in the case of a structure in which the ink path from the ink tank to the ejection port is long, or a structure in which many parts are connected, There are many portions that receive gas permeation from the outside, and the growth rate of bubbles in the liquid chamber flat portion 119 is high.

Further, when the liquid chamber is small, even a relatively small bubble 299 has a large rate of deteriorating the wettability in the nozzle and the liquid chamber.

Further, even at the joint surface 150 between the upper wall 155 of the common liquid chamber 104 and the rear end 151 of the nozzle portion 102, the bubbles 298 tend to stay because of the flat portion, and the staying bubbles 298 stay for a long time. In the continuous printing state, the ink flows back in the ejection direction and is pulled back toward the ejection port 101, which is one of the causes of defective printing.

For this reason, the bubbles 299 (29) are stored especially when stored for a long period of time and when continuously printed for a long time.
In order to prevent the retention and growth of 8), it is necessary to shorten the recovery time interval of the device and increase the frequency of recovery operations.
There is a drawback that the ink consumption (running cost associated with replacement of the ink tank etc.) increases.

Further, in the above-mentioned conventional example, the bonding wire portion 1 is provided further behind the rear end of the top plate on the substrate of the electrothermal converter.
Since 09 is arranged, the area of the substrate extends rearward.
Therefore, the area of the substrate that is larger than the effective area of the liquid chamber and the liquid chamber frame described above is required. For this reason, when a large number of electrothermal converter substrates are simultaneously formed from a single silicon wafer by a film forming apparatus or the like, there is a drawback that the number of substrates taken decreases and the cost increases.

Therefore, an object of the present invention is to provide a structure in which the ink flow path is long, a structure in which many parts are connected, a structure in which the liquid chamber is small, and even when continuous printing is performed for a long time, bubbles in the liquid chamber are generated. It is an object of the present invention to provide an inkjet head and an inkjet recording device that can improve recovery and ensure high-quality recording.

Further, it is an object of the present invention to provide an ink jet head capable of performing recording with less retention and growth of bubbles, less recovery operation, and less ink consumption even in the case of long-term storage.

Further, it is an object of the present invention to provide an inexpensive ink jet head which enables the area of the substrate to be made compact and has good production efficiency.

[0027]

The present invention achieves the above object by the following constitutions.

(1) A substrate on which a plurality of ejection energy generating elements are arranged, and wiring for driving the elements and a wiring portion for electrically connecting the wiring are provided at a rear end portion,
A plurality of ink ejection ports, a nozzle portion that is an ink flow path that communicates with the ink ejection ports, a concave portion that is at least one common liquid chamber that communicates with the nozzle portion, and a supply that communicates with the concave portion through an opening portion. In an inkjet head formed by joining a top plate member including a cylinder, an inner surface from the ink ejection port side of the common liquid quality to the opening is inclined in a counter ejection direction, and the common An inkjet head, wherein an inner surface of the liquid chamber extending from the side opposite to the ink ejection port to the opening is inclined in the same direction as the inclined surface.

(2) A substrate on which a plurality of ejection energy generating elements are arranged and a wiring portion for electrically connecting the wiring for driving the elements and the wiring is provided at a rear end portion,
A plurality of ink ejection ports, a nozzle portion that is an ink flow path that communicates with the ink ejection ports, a concave portion that is at least one common liquid chamber that communicates with the nozzle portion, and a supply that communicates with the concave portion through an opening portion. In an inkjet head formed by joining a top plate member including a cylinder, an inner surface of a nozzle rear end portion of an ink flow path connected to the ink ejection port from the ink ejection port side to the opening of the common liquid chamber An inkjet head characterized in that it is formed with the same inclined surface as.

(3) A substrate on which a plurality of ejection energy generating elements are arranged and a wiring portion for electrically connecting the element driving wiring and the wiring is provided at a rear end portion,
A plurality of ink ejection ports, a nozzle portion that is an ink flow path that communicates with the ink ejection ports, a concave portion that is at least one common liquid chamber that communicates with the nozzle portion, and a supply that communicates with the concave portion through an opening portion. In an inkjet head formed by joining a top plate member including a cylinder, a rear end face of the top plate in the anti-ejection direction corresponding to a rear end part of the substrate in the anti-ejection direction is a joint surface with the substrate. An inkjet head having a shape that does not interfere with a connection portion of the wiring of the substrate.

(4) The ink jet head as described in (3) above, wherein a bonding wire is connected to a connection portion of the wiring provided at a rear end portion of the substrate.

(5) The ink discharge energy generating element is an electrothermal converter that generates heat energy that acts on the ink, (1) to (4).
The inkjet head according to any one of the above.

(6) The inkjet head according to any one of (1) to (5) is equipped with a mounting means for mounting the inkjet head according to any one of (1) to (5). An inkjet recording device characterized by the above.

[0034]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS With the above configuration (1), the inner surface of the common liquid chamber from the ink ejection port side to the opening is inclined in the counter ejection direction, and the common liquid chamber is opposite the ink ejection port side. Since the inner surface from the to the opening is inclined in the same direction as the inclined surface, there is no flat portion on the upper surface of the liquid chamber from the opening of the common liquid chamber of the top plate. This inclined surface shape acts so as to allow the bubbles, which tend to stay on the upper surface of the liquid chamber, to escape to the opening. Furthermore, since the sloped surface shape with a slope shortens the residence time of the bubbles, it acts to prevent the growth of the bubbles themselves,
In addition, at the time of discharge and at the time of recovery, the discharge port (nozzle side)
It works so that the ink can smoothly flow from the opening on the upper surface of the liquid chamber toward.

As a result, the recovery performance is improved, and there is the effect of reducing the retention and growth of bubbles in the liquid chamber even during long-term storage.

Further, according to the above configuration (2), the rear end portion of the nozzle, which is an ink flow path communicating with the ink ejection port, has the same inclined surface as the inner surface from the ink ejection port side of the common liquid chamber to the opening. Therefore, there is no flat portion on the upper surface of the liquid chamber from the rear end portion of the nozzle portion that serves as the ink flow path to the opening portion of the common liquid chamber from the ink ejection port side.

Further, since the inclined surface of the rear end portion of the nozzle portion is a continuous surface having the same inclined surface as the inner surface leading to the opening portion, bubbles generated in the opposite direction of ejection when ink is ejected are generated in the rear end portion of the nozzle portion. After that, it acts to smoothly escape to the opening of the common liquid chamber without staying on the joint surface between the upper surface wall of the common liquid chamber and the rear end of the nozzle portion.

Therefore, even in the continuous printing state for a long time, the recovery performance is improved and the reliability during printing is improved as described above without causing these fine bubbles to flow back into the nozzle portion. Can be secured.

Further, according to the above configuration (3), the rear plate of the top plate corresponding to the rear end of the substrate in the anti-ejection direction escapes the rear end face in the anti-ink ejection direction, and does not interfere with the connection portion of the substrate. Therefore, in order to avoid the interference of the connection part on the substrate with the rear end of the top plate, it is not necessary to extend the substrate rearward and increase the size, and the common liquid chamber and the liquid chamber frame described above are not necessary. This brings about the effect that the area of the substrate approximates the area required for bonding.

Therefore, when a large number of substrates on which the electrothermal converters are formed are simultaneously formed from one silicon wafer by a film forming apparatus or the like, the number of the taken substrates is increased and the cost is reduced.

The embodiment of the present invention will be described in detail with reference to examples.

[0042]

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

FIG. 1 is a perspective view schematically showing a part of an ink jet head which is an embodiment of the present invention.

(First Embodiment) In FIG. 1, 10 is a substrate made of ceramic or the like, and as is well known, an electrothermal converter 11 as a discharge energy generating element is formed by a film forming technique or the like.
(See FIG. 2) are arranged in a plurality. Although not shown, a drive circuit for driving the electrothermal converter 11 is also formed on the substrate 10 at the same time, and a pad 12 for connecting this circuit is arranged at the rear end of the substrate 10. Has been done. Reference numeral 20 is a top plate member joined to the substrate 10, which will be described later in detail. Reference numeral 30 is a wiring board for wiring to the drive circuit of the board 10, and pads 32 are arranged corresponding to the pads 12 of the board 10.

The substrate 10 and the wiring substrate 30 are arranged adjacent to each other on a support plate 40 for heat dissipation made of a metal having a good heat transfer property such as aluminum, and both pads 12 and 32 are
Each is connected by a bonding wire 42.

Next, the first embodiment of the present invention will be further described in detail with reference to FIG. FIG. 2 is BB of FIG.
It is a fragmentary sectional view of a line section.

A plurality of downward ink ejection ports 21 are formed on the top plate 20 in parallel with each other in the direction perpendicular to the plane of the drawing.
Moreover, when bonded to the substrate 10, the ink ejection port 2
A nozzle portion 22 that serves as an ink flow path communicating with 1 is formed as a plurality of grooves. Reference numeral 23 denotes a concave portion formed in the liquid chamber frame portion 26 so as to be a common liquid chamber communicating with the plurality of nozzle portions 22, and the concave portion (common liquid chamber) 23 has ink integrated with the liquid chamber frame body 26. Ink passage 2 in supply cylinder 24
7 communicate with each other through the opening 25. The opening portion here means the boundary portion between the ink passage 27 in the ink supply cylinder 24 and the common liquid chamber 23.

The ink discharge port 21 of the common liquid chamber 23
From the side, that is, from the communicating portion with the nozzle portion 22 to the opening portion
The inner surface 26A extending to the opposite side is inclined in the opposite ejection direction, and the inner surface 26B extending from the opposite ink ejection port side to the opening 25 is also inclined in the same direction as the inner surface 26A. However, the inner surface 26
The inclination angle of A is larger than the inclination angle of the inner surface 26B. This is the common liquid chamber 2 while obtaining the desired effect.
This is to increase the capacity within 3.

Further, the liquid chamber frame portion 26 corresponding to the rear end portion of the top plate 20 on which the pad 12 of the substrate 10 is arranged is a part of the top plate 20.
The rear end surface 26C is a relief surface having an inclination substantially the same as that of the inner surface 26B, and the relief portion 28 (see FIG.
(Refer to FIG. 4) is formed, and interference with the connection portion where the pad 12 and the bonding wire 42 are arranged is avoided.

According to the first embodiment, since the inner surfaces 26A and 26B of the common liquid chamber 23 are formed into a plane shape having a slope toward the opening 25, the common liquid chamber 23 extends from the opening 25 to the upper surface of the liquid chamber. There is no flat part. Therefore, even if bubbles are generated in the common liquid chamber 23, the inner surfaces 26A and 26B having the inclined gradient can escape the bubbles, which are trying to stay on the upper surface of the common liquid chamber 23, to the opening 25. Furthermore, since the residence time of the bubbles is shortened on the inner surfaces 26A and 26B having a slope, the growth of the bubbles themselves is prevented.

Further, the inclined inner surfaces 26A and 26B guide the ink so as to smoothly flow toward the ink ejection port 21 (nozzle portion 22) at the time of ejecting and recovering the ink, so that the flow line is not disturbed and the ink is smoothly supplied. To be done. Thereby, the recovery performance is improved, and the retention and growth of bubbles in the liquid chamber are reduced even in the case of long-term storage.

Here, the joint surface portion between the nozzle portion 22 and the common liquid chamber 23 will be described in detail with reference to FIG. FIG. 3 is a partial cross-sectional view illustrating details of the nozzle portion 22 of FIG.

In FIG. 3, 50 is the upper wall 5 of the common liquid chamber 23.
5 is a joint surface (rear end portion inclined surface) between the nozzle 5 and the rear end portion 51 of the nozzle portion 22. A plurality of ink ejection ports 21 are provided in the ejection direction of the nozzle portion 22. Further, the top plate 20 is the substrate 1
0, and the electrothermal conversion element 11 is arranged on the substrate 10.

Here, the rear end portion 51 of the nozzle portion 22, which serves as an ink flow path connected to the ink ejection port 21, is formed with the same inclined surface as the inner surface 55 from the ink ejection port side of the common liquid chamber to the opening. There is. That is, there is no flat portion on the upper surface 50 of the liquid chamber from the rear end of the nozzle that serves as the ink flow path to the opening of the common liquid chamber from the ink ejection port side.

The nozzle portion and the end inclined surface 50 are
It is a continuous surface with the same slope as the inner surface leading to the opening.

With this structure, according to the present embodiment, bubbles in the opposite ejection direction, which are generated when ejecting ink, pass between the nozzle rear end portion 51 and the upper surface wall portion of the common liquid chamber and the rear end portion of the nozzle portion. It is possible to smoothly escape to the opening of the common liquid chamber without staying on the joint surface.

Further, according to this embodiment, as shown in FIG. 2, the rear end face of the top plate 20 in the direction opposite to the ink ejection direction is the escape face 2.
Since it is 6C, the area occupied by the drive circuit for the electrothermal conversion element 11 and the like can be reduced and the substrate 10 can be made compact without interfering with the connecting portion including the bonding wire 42 and the like. You can

(Second Embodiment) FIG. 4 is a partial sectional view taken along the line CC of FIG. 1 showing a second embodiment of the present invention. The appearance of the ink jet head of this embodiment is the same as that of the first embodiment, so refer to FIG.

The second embodiment differs from the previous embodiment in that the inner surface of the common liquid chamber 23 on the side opposite to the ink ejection port is provided with two inclined surfaces 26B ₁ and 2 in order to increase the volume of the common liquid chamber 23.
It is 6B ₂ . That is, the inner surface 26B ₁ has substantially the same inclination angle as the inner surface 26B of the previous embodiment, while the inner surface 26B ₂ has a smaller inclination angle, and is closer to the substrate 10 at a right angle. Since other configurations are the same as those in the previous embodiment, the same functional parts are designated by the same reference numerals to avoid redundant description.

(Third Embodiment) Next, FIG. 5 shows an example of an ink jet recording apparatus IJRA in which an ink jet head according to the present invention is mounted.

The inkjet head IJH has an ink supply cylinder 24 detachably attached to the ink supply port of an ink tank, and is mounted as an integral inkjet cartridge IJC on the carriage HC with the ink ejection port 21 facing downward. Here, the carriage HC is a guide lock 5
003 is slidably guided by a motor 5013 and a gear 501.
2, 5011, 5009 and a lead screw 5004 on which a feed screw 5005 is formed are reciprocated in the directions of arrows a and b. Therefore, the inkjet head IJH mounted on the carriage HC reciprocates while facing the paper P on the platen 5000. Reference numerals 5007 and 5008 denote photocouplers, which detect the home position when the lever 5006 moves in and out. Reference numeral 5022 denotes a cap member that comes into contact with the ejection surface of the inkjet head IJH, and the opening 5
The suction recovery of the inkjet head IJH is performed via 023. Reference numeral 5017 is a cleaning blade.

The capping, cleaning, and suction recovery are carried out at the respective corresponding positions, and desired operations are performed.

(Others) In particular, the present invention is provided with a means (for example, an electrothermal converter or a laser beam) for generating thermal energy as energy used for ejecting ink, especially in the ink jet recording system. A recording head of the type that causes a change in the state of the ink by the thermal energy, and provides an excellent effect in a recording apparatus. This is because according to such a method, it is possible to achieve higher density and higher definition of recording.

The typical structure and principle are described in, for example, US Pat. Nos. 4,723,129 and 4,740.
What is done using the basic principles disclosed in 796 is preferred. This method is a so-called on-demand type,
Although it can be applied to any of the continuous type, in particular, in the case of the on-demand type, it can be applied to the sheet holding the liquid (ink) or the electrothermal converter arranged corresponding to the liquid path. By applying at least one drive signal that gives a rapid temperature rise over the nucleate boiling corresponding to the recording information, heat energy is generated in the electrothermal converter, and film boiling occurs on the heat acting surface of the recording head. Liquid (ink) corresponding to this drive signal in a one-to-one correspondence
It is effective because bubbles can be formed inside. The liquid (ink) is ejected through the ejection opening by the growth and contraction of the bubble to form at least one droplet. It is more preferable to make this drive signal into a pulse shape because bubbles can be immediately and appropriately grown and contracted, so that liquid (ink) ejection with excellent responsiveness can be achieved. As the pulse-shaped drive signal, those described in US Pat. Nos. 4,463,359 and 4,345,262 are suitable. If the conditions described in US Pat. No. 4,313,124 of the invention relating to the rate of temperature rise of the heat acting surface are adopted, more excellent recording can be performed.

As the constitution of the recording head, in addition to the combination constitution of the discharge port, the liquid passage, and the electrothermal converter (straight liquid passage or right-angled liquid passage) as disclosed in the above-mentioned respective specifications. US Pat. No. 4,558,333, US Pat. No. 4,558,333, which discloses a configuration in which a heat acting portion is arranged in a bending region.
The structure using the specification of No. 59600 is also included in the present invention. In addition, Japanese Unexamined Patent Publication No. 59-123670 discloses a configuration in which a common slit is used as a discharge portion of the electrothermal converter for a plurality of electrothermal converters, and an opening for absorbing a pressure wave of thermal energy is provided. The effect of the present invention is effective even if the configuration corresponding to the ejection portion is disclosed in JP-A-59-138461. That is, according to the present invention, recording can be surely and efficiently performed regardless of the form of the recording head.

Further, the present invention can be effectively applied to a full-line type recording head having a length corresponding to the maximum width of a recording medium on which a recording apparatus can record. Such a recording head may have a configuration that satisfies the length by a combination of a plurality of recording heads or a configuration as one recording head integrally formed.

In addition, even in the case of the serial type as in the previous example, the recording head fixed to the apparatus main body or the ink is supplied from the apparatus main body by being electrically connected to the apparatus main body by being attached to the apparatus main body. The present invention is also effective when a replaceable chip type recording head capable of performing the above or a cartridge type recording head in which an ink tank is integrally provided in the recording head itself is used.

Further, it is preferable to add a discharge recovery means for the recording head, a preliminary auxiliary means, etc. to the present invention as the constitution of the recording device, because the effect of the present invention can be further stabilized. Specifically, heating is performed by using a capping unit, a cleaning unit, a pressure or suction unit for the recording head, an electrothermal converter or a heating element other than this, or a combination thereof. Examples thereof include a preliminary heating unit for performing the discharge and a preliminary discharge unit for performing discharge different from the recording.

The type and number of recording heads to be mounted are not limited to those provided only for one color ink, and for a plurality of inks having different recording colors and densities. A plurality may be provided. That is, for example, the recording mode of the recording apparatus is not limited to the recording mode of only the mainstream color such as black, but it may be either the recording head is integrally formed or a plurality of combinations may be used. The present invention is also extremely effective for an apparatus provided with at least one of full-color recording modes by color mixing.

In addition, in the embodiments of the present invention described above, the ink is described as a liquid. However, an ink which solidifies at room temperature or lower and which softens or liquefies at room temperature may be used. In general, the ink jet method generally controls the temperature of the ink itself within a range of 30 ° C. or more and 70 ° C. or less to control the temperature so that the viscosity of the ink is in a stable ejection range. Sometimes, the ink may be in a liquid state. In addition, the temperature rise due to thermal energy is positively prevented by using it as the energy of the state change from the solid state of the ink to the liquid state, or in order to prevent the evaporation of the ink, it is solidified and heated in the standing state. You may use the ink liquefied by. In any case, by applying heat energy such as ink that is liquefied by applying heat energy according to the recording signal and liquid ink is ejected or that begins to solidify when it reaches the recording medium. The present invention can be applied to the case where an ink having a property of being liquefied for the first time is used. In this case, the ink is
JP-A-54-56847 or JP-A-60-7
As described in Japanese Patent No. 1260, it may be configured to face the electrothermal converter in a state of being held as a liquid or a solid in the concave portion or the through hole of the porous sheet. In the present invention, the most effective one for each of the above-mentioned inks is to execute the above-mentioned film boiling method.

In addition, the form of the ink jet recording apparatus of the present invention is not limited to the one used as an image output terminal of an information processing apparatus such as a computer, a copying apparatus combined with a reader or the like, and a facsimile apparatus having a transmission / reception function. It may take a form.

[0072]

As is apparent from the above description, according to the first aspect of the present invention, since the retention and growth of bubbles in the liquid chamber can be reduced, the recovery operation is reduced and the ink consumption amount is reduced. A small number of inkjet heads can be obtained.

Further, according to the second aspect of the invention, since the retention and growth of bubbles in the liquid chamber during printing can be reduced, the printing quality is improved and the recovery operation is small and the ink consumption is small. An inkjet head with a small amount can be obtained.

Further, according to the invention described in claim 3, since it is not necessary to extend the substrate rearward to increase the size in order to avoid interference, the substrate on which the electrothermal converter is formed can be formed. When a plurality of silicon wafers are simultaneously formed from one silicon wafer by a film device or the like, the number of the silicon wafers to be taken increases and the cost can be reduced.

According to the invention described in claim 6,
By installing an inkjet head having the above effect,
It is possible to carry out stable and high-quality recording.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of an inkjet head according to the present invention.

FIG. 2 is a sectional view taken along line BB in FIG. 1 showing a first embodiment of the inkjet head of the present invention.

FIG. 3 is a partial cross-sectional view of FIG. 2 showing a first embodiment of the inkjet head of the present invention.

FIG. 4 is a sectional view taken along line CC of FIG. 1 showing a second embodiment of the inkjet head of the present invention.

FIG. 5 is a perspective view showing an example of an inkjet recording apparatus in which the inkjet head of the present invention is mounted.

FIG. 6 is a perspective view showing a configuration of a conventional inkjet head.

7 is a cross-sectional view taken along the line AA of FIG. 6 showing the configuration of a conventional inkjet head.

FIG. 8 is a partial cross-sectional view showing a configuration of a nozzle portion of a conventional inkjet head.

[Explanation of symbols]

 10 Substrate 11 Electrothermal Converter 12 Pad 20 Top Plate 21 Ink Ejection Port 22 Nozzle Part 23 Common Liquid Chamber 24 Ink Supply Cylinder 25 Opening 26 Liquid Chamber Frame 26A, 26B (Inclined) Inner Surface 27 Ink Passage 28 Relief 30 Wiring Substrate 32 Pad 36 Wiring substrate 40 Support plate 42 Bonding wire 51 Nozzle rear end portion 50 Inclined joint surface between nozzle rear end portion and common liquid chamber portion 55 Inclined surface of common liquid chamber portion

Claims (6)

[Claims] 1. A substrate in which a plurality of ejection energy generating elements are arranged, a wiring for electrically driving the elements and a wiring portion for electrically connecting the wiring are provided at a rear end portion, and a plurality of ink ejection elements are provided. An outlet, a nozzle portion that serves as an ink flow path that communicates with the ink ejection port, a recess that serves as at least one common liquid chamber that communicates with the nozzle portion, and a supply cylinder that communicates with the recess through an opening. In an ink jet head formed by joining a top plate member and a top plate member, an inner surface from the ink ejection port side of the common liquid quality to the opening is inclined in a counter ejection direction and An inkjet head, wherein an inner surface from the ink ejection port side to the opening is inclined in the same direction as the inclined surface. 2. A substrate on which a plurality of ejection energy generating elements are arranged, a wiring for electrically driving the elements and a wiring portion for electrically connecting the wiring are provided at a rear end portion, and a plurality of ink ejection elements are provided. An outlet, a nozzle portion that serves as an ink flow path that communicates with the ink ejection port, a recess that serves as at least one common liquid chamber that communicates with the nozzle portion, and a supply cylinder that communicates with the recess through an opening. In the ink jet head formed by joining the top plate member and the top plate member, the nozzle rear end portion of the ink flow path connected to the ink ejection port has the same inclination as the inner surface from the ink ejection port side of the common liquid chamber to the opening. An inkjet head characterized by being formed by a surface. 3. A substrate on which a plurality of ejection energy generating elements are arranged, a wiring for electrically driving the elements, and a wiring portion for electrically connecting the wiring are provided at a rear end portion, and a plurality of ink discharging elements. An outlet, a nozzle portion that serves as an ink flow path that communicates with the ink ejection port, a recess that serves as at least one common liquid chamber that communicates with the nozzle portion, and a supply cylinder that communicates with the recess through an opening. In an inkjet head formed by joining a top plate member and a top plate member, a rear end face of the top plate in the anti-ejection direction corresponding to a rear end part of the substrate in the non-ejection direction is released from a joint surface with the substrate. 2. An ink jet head having a shape that does not interfere with the connection portion of the wiring. 4. The inkjet head according to claim 3, wherein a bonding wire is connected to a connection portion of the wiring provided at a rear end portion of the substrate. 5. The ink ejection energy generating element,
The ink jet head according to any one of claims 1 to 4, wherein the ink jet head is an electrothermal converter that generates heat energy that acts on ink. 6. An inkjet recording apparatus comprising a mounting means for mounting the inkjet head according to any one of claims 1 to 5, comprising the inkjet head according to any one of claims 1 to 5. .