JP2002019121A - Ink jet recording head and its manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a highly reliable ink jet recording head having stable discharge characteristics and its manufacturing method. SOLUTION: This ink jet recording head includes a nozzle part having ink discharge openings for discharging ink and ink channels communicating with the ink discharge openings, a recording element substrate having elements for generating an energy used for discharging the ink and, a wiring board connected electrically to the recording element substrate. The ink jet recording head is provided with spacers in the vicinity of electrodes connected electrically to the wiring board. The spacer is formed of the same material as that of the nozzle part and is made lower than a height of a face of the nozzle part where the ink discharge openings are formed. The manufacturing method for the recording head includes steps of applying a photosensitive coating resin layer two or more times thereby forming a plurality of the photosensitive coating resin layers, exposing to light the layers after applying a middle layer and after applying a final layer, and forming the spacers of an arbitrary height.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording head for performing recording by discharging ink droplets by means of discharge energy from an element generating energy used for discharging ink, and a method of manufacturing the same.

[0002]

2. Description of the Related Art In general, an ink jet recording head applied to an ink jet recording method (liquid jet recording method) is used for discharging fine ink ejection ports, ink flow paths, and ink provided in a part of the ink flow paths. A plurality of elements for generating energy to be used are provided. In order to obtain a high-quality image with such an ink jet recording head, droplets of the ink liquid ejected from the ink ejection ports are always ejected from each ink ejection port at the same volume and the same ejection speed. It is desirable. In particular, it goes without saying that the smaller the ejected droplet, the greater the effect on image quality.

In order to achieve this, a special opening and closing 4-109
In Japanese Patent Application Laid-Open No. 40-10942, an electrothermal conversion element is employed as an element for generating energy used for discharging ink, a drive signal is applied to the element in accordance with recording information, and the ink is supplied to the electric conversion element. A recording method and a recording apparatus are disclosed, in which thermal energy that gives a sharp temperature rise exceeding nucleate boiling is generated, bubbles are formed in ink, and the bubbles are communicated with outside air to discharge ink droplets. I have.

[0004] As a method for manufacturing such a printing method or an ink jet print head used in a printing apparatus, a manufacturing method described in Japanese Patent Application Laid-Open No. 6-286149 has been proposed. Further, there has been proposed a method of electrically connecting a recording element substrate on which elements for generating energy used for discharging ink, an ink discharge port and the like are formed, and the surroundings.

The prior art will be briefly described below with reference to FIGS.

FIG. 2A is a perspective view of the base 1 showing a state in which a heater 2 as an element for generating energy used for discharging ink on the base 1 is disposed.
FIGS. 2B to 2H are cross-sectional views taken along the line AA in FIG.
A recording element substrate formed in a conventional ink jet recording head (here, only the nozzle portion is shown).
It is a schematic diagram showing a manufacturing process.

As shown in FIG. 2B, a mold resist layer 3 as an ink flow path pattern is formed on a substrate 1 on which a heater 2 is disposed (FIG. 2C). A first photosensitive coating resin layer 4 serving as an ink flow path wall (that is, serving as a nozzle forming member) is further formed on the first photosensitive coating resin layer 4 (FIG. 2D). Then, a second photosensitive coating resin layer 5 having water repellency is formed (FIG. 2E).

Next, the first photosensitive coating resin layer 4 and the second photosensitive coating resin layer 5 are exposed and developed by a usual photolithography technique through a mask, and are used for discharging ink. The hydrophilic portion 7 is formed at an arbitrary position on the ink discharge port 6 and the nozzle surface above the heater 2 which is an element for generating the energy (FIG. 2F). Here, in the portion where the ink discharge port 6 is formed, a mask pattern is set to a size in which the first photosensitive coating resin layer 4 and the second photosensitive coating resin layer 5 are patterned (are not left after development), and the hydrophilic portion is formed. 7, the second photosensitive coating resin layer 5 is patterned, but the first photosensitive coating resin layer 4 is patterned.
Is set to a size that is not patterned (does not penetrate during development). In the hydrophilic portion 7, the second photosensitive coating resin layer 5 having water repellency is partially missing, and the first photosensitive coating resin layer 4 is exposed, and thus does not exhibit water repellency.

After the ink discharge port 6 and the hydrophilic portion 7 are formed, an ink supply port 8 is formed (FIG. 2G), and finally, the mold resist layer 3 is removed to form an ink flow path (FIG. 2G). 2 (h), recording of the ink jet recording head in which the ink discharge port 6 and the heater 2 face each other with the ink flow path interposed therebetween, and the flow of ink is changed to a right angle near the heater 2 toward the ink discharge port. An element substrate is manufactured.

Next, a description will be given of a process of electrically connecting the printing element substrate manufactured as described above to the surroundings, for example, a wiring substrate via a conductive sheet. FIG.
(E) shows the connection process.

As shown in FIG. 3A, a bump 10 is formed on an aluminum pad 9 as an electrode disposed on a substrate for electrical connection with the surroundings (FIG. 3B). Anisotropic conductive sheet (hereinafter referred to as “A
CF ". ) 11 is positioned above bump 10 (FIG. 3C). Next, toward the bump 10, the ACF
By applying heat pressure to the ACF 11, the ACF 11 exhibits conductivity and is electrically connected (FIG. 3D). Finally, the connection portion is sealed with the sealing material 12 to complete the connection process (FIG. 3D). FIG. 3 (e). In such an electrical connection, A
When heat pressure is applied to CF11, ACF11 and bump 10
Not only between the ACF 11 but also between the ACF 11 and the substrate, a problem may occur in which the ACF 11 and the substrate are directly connected to each other at portions other than the bumps 10.

In order to eliminate this problem, as shown in FIG. 4, the first and second photosensitive coating resin layers 4 and 5 forming the nozzle portion 14 are provided with a spacer 13 around the aluminum pad 9.
Has been arranged. When the spacer 13 is formed of the first and second photosensitive coating resin layers 4 and 5 as described above, the sealing material is repelled in the sealing process because the second photosensitive coating resin layer 5 has water repellency. In some cases, complete sealing is not performed.

Therefore, by subjecting the spacer 13 to hydrophilic treatment, repelling of the sealing material can be prevented, complete sealing treatment can be performed, and direct conduction between the substrate and the ACF can be prevented.

[0014]

As described above, in order to obtain the same quality and high speed of the ink droplets ejected from the ink ejection ports in order to obtain a high quality image, a side shooter system is particularly required. In the case of (a method in which ink ejection ports are arranged in a direction perpendicular to a substrate having a heater), it is preferable that the distance between an element that generates energy used for ejecting ink and the ink ejection ports be somewhat large. It was found that droplet management was easy. In order to increase the distance between an element (heater) that generates energy used for discharging ink and the ink discharge port, in the above-described conventional method of manufacturing an ink jet recording head, the first photosensitive coating resin layer is thickened. There is a need. That is, the first photosensitive coating resin material must be applied thickly. As a method of applying the photosensitive coating resin material thickly, for example, in the case of applying by a spin coater (a coating device using a spin coating method), a method of increasing the concentration of the resin material or reducing the rotation speed of the spin coater is adopted. However, in both methods, the thickness distribution of the entire resin layer to be formed tends to deteriorate. Further, when the photosensitive coating resin material is applied thickly, irregularities on the surface of the mold resist layer cannot be absorbed, and the ink flow path wall finally formed by the first photosensitive coating resin layer is not formed smoothly. In other words, the distance between the element that generates energy used to discharge ink and the ink discharge port varies from nozzle to nozzle. Further, as the first photosensitive coating resin layer becomes thicker, the height of the spacer naturally increases, and there is a problem that the spacer cannot function as a spacer for connection between the conductive sheet and the electrode.

[0015]

According to the present invention, there is provided a nozzle having at least an ink discharge port for discharging ink and an ink flow path communicating with the ink discharge port, and a nozzle for discharging the ink. A recording element substrate having an element generating energy to be applied, and a wiring substrate electrically connected to the recording element substrate, wherein the recording element substrate has an electrode electrically connected to the wiring substrate. And an ink jet recording head comprising a spacer formed of the same material as the nozzle portion and having a height lower than the height of the ink discharge port forming surface in the nozzle portion, and an ink discharge port for discharging at least ink as a method of manufacturing the same. And a nozzle portion having an ink flow path communicating with the ink discharge port, and a nozzle portion for discharging the ink. In a method for manufacturing an ink jet print head, comprising: a printing element substrate having an element generating energy to be applied; and a wiring board electrically connected to the printing element substrate, the printing substrate is electrically connected to the wiring board on a base. Forming an electrode and the element, forming an ink flow path pattern with a soluble resin on a substrate having the element and the electrode, and forming an ink flow path wall on the ink flow pattern Forming a plurality of photosensitive coating resin layers by coating the photosensitive coating resin layer at least twice, exposing after the application of the intermediate layer and after the application of the final layer, and forming a spacer of an arbitrary height; A step of forming an ink discharge port in the photosensitive coating resin layer at a position opposed to the element; and a step of eluting the soluble resin. And to provide a production method.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS First, a recording apparatus having an ink jet recording head according to the present invention will be described with reference to FIGS.

In the recording apparatus described below, a printer will be described as an example of a recording apparatus using an ink jet recording method.

In this specification, "print"
(Sometimes referred to as “records.”) Is not only the case where significant information such as characters and figures are formed, but also significant or insignificant, and is manifested so that humans can perceive it visually. Regardless of whether or not the image, pattern, pattern, and the like are widely formed on a print medium or the medium is processed.

Here, the term "print medium" (sometimes referred to as "recording sheet") means not only paper used in a general printing apparatus but also a wide range of cloth, plastic,
Films, metal plates, glass, ceramics, wood, leather, etc., which can accept ink, are also referred to.

Further, "ink" (sometimes referred to as "liquid") is to be interpreted widely as in the definition of "print" described above. , Or a liquid that can be subjected to processing of a print medium or processing of ink (for example, solidification or insolubilization of a coloring material in ink applied to a print medium).

[Apparatus Main Body] FIGS. 5 and 6 show a schematic configuration of a printer using an ink jet recording system. In FIG. 5, an apparatus main body M100 of a printer as a recording apparatus
The outer case of 0 is the lower case M1001, the upper case M100
2. Access cover M1003 and discharge tray M100
4 and a chassis M3019 (see FIG. 6) housed in the exterior member.

The chassis M3019 is composed of a plurality of plate-like metal members having a predetermined rigidity, forms a skeleton of a recording apparatus, and holds each recording operation mechanism described later.

The lower case M1001 forms a substantially lower half of the exterior of the apparatus main body M1000, and the upper case M1002 forms a substantially upper half of the exterior of the apparatus main body M1000. It has a hollow body structure having a storage space for storing each mechanism described below.
Openings are formed in the upper surface and the front surface of the apparatus main body M1000, respectively.

Further, one end of the discharge tray M1004 is rotatably held by the lower case M1001, and the opening formed on the front surface of the lower case M1001 can be opened and closed by the rotation. For this reason, when performing the recording operation, the discharge tray M100
By rotating the opening 4 to the front side to open the opening, the recording sheets can be discharged from here, and the discharged recording sheets P can be sequentially stacked.
The discharge tray M1004 has two auxiliary trays M.
1004a and M1004b are accommodated, and the tray support area can be expanded or reduced in three stages by pulling out each tray as needed.

One end of the access cover M1003 is rotatably held by the upper case M1002 so that an opening formed on the upper surface can be opened and closed. When the access cover M1003 is opened, the access cover M1003 is opened. The stored recording head cartridge H1000 or ink tank H1900 can be replaced. Although not particularly shown here, the access cover M10
When the cover 03 is opened and closed, a projection formed on the back surface rotates the cover opening / closing lever, and the open / closed state of the access cover can be detected by detecting the rotation position of the lever with a microswitch or the like. It has become.

A power key E0018 and a resume key E0019 are provided on the rear upper surface of the upper case M1002.
Is provided so as to be pressed, and an LED E0020 is provided. When the power key E0018 is pressed, L
The ED E0020 lights up to notify the operator that recording is possible. LED E0
Reference numeral 020 has various display functions such as changing the blinking method and color, and notifying an operator of a printer trouble or the like. Further, the buzzer E0021 (FIG. 12) can be smoothed. If the troubles are resolved,
Recording is restarted by pressing the resume key E0019.

[Printing Operation Mechanism] Next, the printing operation mechanism according to the present embodiment, which is housed and held in the apparatus main body M1000 of the printer, will be described.

The recording operation mechanism in the present embodiment includes an automatic feeding unit M3022 for automatically feeding the recording sheet P into the apparatus main body, and a recording sheet P sent one by one from the automatic feeding unit. A conveyance section M3029 for guiding the recording sheet P from the recording position to the discharge section M3030 while guiding the recording sheet P to a predetermined recording position; and a recording sheet P conveyed to the recording position.
And a recovery unit (M5000) for performing recovery processing on the recording unit and the like.

(Recording Unit) Here, the recording unit will be described. The recording unit includes a carriage M4001 movably supported by a carriage shaft M4021, and a recording head cartridge H1000 removably mounted on the carriage M4001. Consists of

Recording Head Cartridge First, the recording head cartridge used in the recording section will be described with reference to FIGS.

As shown in FIG. 3, the recording head cartridge H1000 according to this embodiment includes an ink tank H1900 for storing ink and an ink tank H190.
And a recording head H1001 that ejects ink supplied from nozzles from nozzles according to recording information. The recording head H1001 employs a so-called cartridge system which is removably mounted on a carriage M4001 described later.

The recording head cartridge H10 shown here
In FIG. 4, in order to enable photographic high-quality color recording, for example, ink tanks H1900 independent of each color of black, light cyan, light magenta, cyan, magenta and yellow are prepared as ink tanks. As shown in FIG.
1 is detachable.

As shown in an exploded perspective view of FIG. 9, the recording head H1001 includes a recording element substrate H1100, a first plate H1200, an electric wiring substrate H1300, a second plate H1400, a tank holder H1500,
It is composed of a flow path forming member H1600, a filter H1700, and a seal rubber H1800.

On the printing element substrate H1100, a plurality of printing elements for ejecting ink to one side of the Si substrate, and electric wiring such as Al for supplying power to each printing element are formed by a film forming technique. A plurality of ink flow paths and a plurality of ejection ports H1100T corresponding to the recording elements are formed by photolithography, and an ink supply port for supplying ink to the plurality of ink flow paths is formed to open on the back surface. Have been. The printing element substrate H1100 is bonded and fixed to a first plate H1200, and an ink supply port H1201 for supplying ink to the printing element substrate H1100 is formed here. Further, a second plate H1400 having an opening is adhered and fixed to the first plate H1200, and the electric wiring board H13 is connected via the second plate H1400.
00 is held so as to be electrically connected to the printing element substrate H1100. This electric wiring board H1300
Is for applying an electric signal for discharging ink to the recording element substrate H1100.
0 and an external signal input terminal H located at an end of the electric wiring for receiving an electric signal from the main body.
1301 and an external signal input terminal H1301
Are positioned and fixed on the back side of a tank holder H1500 described later.

On the other hand, a flow path forming member H1600 is fixed to the tank holder H1500 for detachably holding the ink tank H1900, for example, by ultrasonic welding, and an ink flow path H1501 extending from the ink tank H1900 to the first plate H1200. Is formed. Further, a filter H1700 is provided at an end portion of the ink flow path H1501 on the ink tank side which engages with the ink tank H1900, so that intrusion of dust from the outside can be prevented. In addition, a seal rubber H1800 is attached to an engagement portion with the ink tank H1900, so that evaporation of ink from the engagement portion can be prevented.

Further, as described above, the tank holder H1
500, flow path forming member H1600, filter H170
And a tank element comprising a recording element substrate H1100, a first plate H1200, an electric wiring substrate H1300, and a second plate H1400, which are joined together by bonding or the like. This constitutes the recording head H1001.

(Carriage) Next, referring to FIG. 6, a carriage M on which the recording head cartridge H1000 is mounted
4001 will be described.

As shown in FIG. 6, the carriage M4001
Has a recording head H10 that engages with the carriage M4001.
01, a carriage cover M4002 for guiding the recording head H1001 to a predetermined mounting position on the carriage M4001, a head set lever M4007 that engages with the tank holder H1500 of the recording head H1001 and presses the recording head H1001 to the predetermined mounting position. Is provided. That is, the head set lever M4007 is provided above the carriage M4001 so as to be rotatable with respect to the head set lever shaft, and a spring-biased head set plate (not shown) is provided at an engagement portion with the recording head H1001. The recording head H1001 is mounted on the carriage M4001 while being pressed by the spring force.

A contact flexible print cable (refer to FIG. 11, hereinafter referred to as a contact FP) is provided at another engagement portion of the carriage M4001 with the recording head H1001.
C), and a contact FPC
A contact portion on E0011 and a contact portion (external signal input terminal) H130 provided on print head H1001
1 makes electrical contact with each other so that various kinds of information for recording and reception, power supply to the recording head H1001, and the like can be performed.

Here, an elastic member such as rubber (not shown) is provided between the contact portion of the contact FPC E0011 and the carriage M4001, and the contact portion is formed by the elastic force of the elastic member and the pressing force of the headset lever spring. The secure contact with the carriage M4001 is enabled. Further, the contact FPC
E0011 is connected to a carriage substrate E0013 mounted on the back of the carriage M4001 (FIG. 11).
reference).

[Scanner] The printer in this embodiment can be used as a reading device by mounting a scanner on the carriage M4001 instead of the recording head cartridge H1000 described above.

This scanner moves in the main scanning direction together with the carriage M4001 on the printer side, and reads a document image fed instead of a recording medium in the course of movement in the main scanning direction. By alternately performing the reading operation in the main scanning direction and the feeding operation of the document in the sub-scanning direction, one document image information can be read.

FIGS. 10A and 10B show a scanner M6000 for explaining a schematic configuration of the scanner M6000.
It is a figure which shows 6000 turned upside down.

As shown, the scanner holder M6001
Has a substantially box-like shape, and contains therein an optical system and a processing circuit necessary for reading. When the scanner M6000 is mounted on the carriage M4001, a reading unit lens M60 is provided at a portion facing the original surface.
The lens M6006 converges the reflected light from the document surface to an internal reading unit to read the document image. On the other hand, the illumination unit lens M6005 has a light source (not shown) inside, and light emitted from the light source is applied to the document via the lens M6005.

The scanner cover M6003 fixed to the bottom of the scanner holder M6001 is attached to the scanner holder M6.
The inside of 001 is fitted so as to shield light, and the operability of attaching and detaching to and from the carriage M4001 is improved by louver-shaped grips provided on the side surface. Scanner holder M60
01 has substantially the same outer shape as the recording head H1001, and can be attached to and detached from the carriage M4001 by the same operation as the recording head cartridge H1000.

The scanner holder M6001 houses a substrate having a read processing circuit, and a scanner contact PCB connected to the substrate is provided so as to be exposed to the outside. The scanner M6000 is mounted on the carriage M4001. Scanner contact PC when attached
B M6004 contacts the contact FPC E0011 on the carriage M4001 side, and the substrate is moved to the carriage M4.
001 is electrically connected to a control system on the main body side.

[Configuration of Electric Circuit of Printer] Next, an electric circuit configuration in the embodiment of the present invention will be described. Figure 1
FIG. 1 is a diagram schematically showing an example of the overall configuration of an electric circuit according to this embodiment.

The electric circuit in this embodiment mainly includes a carriage board (CRPCB) E0013 and a main PC.
B (Printed Circuit Board) E0014, power supply unit E0015 and the like. Here, the power supply unit E0015 is connected to the main PCB E0014 and supplies various drive powers.

The carriage substrate E0013 is a printed circuit board unit mounted on the carriage M4001 (FIG. 6). The carriage substrate E0013 functions as an interface for transmitting and receiving signals to and from the recording head through the contact FPC E0011. Based on the pulse signal output from the encoder sensor E0004, a change in the positional relationship between the encoder scale E0005 and the encoder sensor E0004 is detected, and the output signal is converted to a flexible flat cable (CRFFC) E.
0012 to the main PCB E0014.

Further, a main PCBE0014 is a printed circuit board unit which controls the driving of each part of the ink jet recording apparatus in this embodiment, and includes a paper end detection sensor (PE sensor) E0007, an ASF (automatic paper feeder) sensor E0009, and a cover sensor. E0022, a parallel interface (parallel I / F) E0016, a serial interface (serial I / F) E0017, a resume key E0019, an LED E0020, a power key E0018, a buzzer E0021, and the like are provided on the board. Furthermore, the carriage M140
A motor (CR motor) E0001 serving as a drive source for main scanning of 0, a motor (LF motor) E0002 serving as a drive source for conveying a recording medium, and a rotating operation of a recording head and a paper feeding operation of the recording medium. In addition to being connected to a shared motor (PG motor) E0003 to control these drives, the ink empty sensor E0006, the GAP sensor E0008, the PG sensor E0010, the CRFFC E0
012, a connection interface with the power supply unit E0015.

FIG. 12 is a block diagram showing the internal configuration of the main PCB E0014. In the figure, E100
Reference numeral 1 denotes a CPU. The CPU E1001 has a clock generator (PCG) E1002 connected to an oscillation circuit E1005 inside, and its output signal E101
9 generates a system clock. ROM E1004 and ASIC through control bus E1014.
(Application Specific Integrated Circuit) E10
06, control of the ASIC E1006, an input signal E1017 from the power key, and an input signal E from the resume key in accordance with a program stored in the ROM.
1016, a cover detection signal E1042, and a head detection signal (HSENS) E1013 are detected, and a buzzer E0018 is generated by a buzzer signal (BUZ) E1018.
A / D converter E1003 that drives the built-in A / D converter 21
Empty detection signal (INKS) E connected to
1011 and temperature detection signal (TH) E by thermistor
While detecting the state of 1012, it performs various other logical operations and condition determinations, and controls the driving of the ink jet printing apparatus.

Here, the head detection signal E1013 is transmitted from the print head cartridge H1000 to the flexible flat cable E0012, the carriage substrate E0013, and the contact flexible print cable E0011.
, An ink empty detection signal E1011 is an analog signal output from the ink empty sensor E0006, and a temperature detection signal E1012 is output from a thermistor (not shown) provided on the carriage substrate E0013. Is an analog signal.

E1008 is a CR motor driver which uses a motor power supply (VM) E1040 as a drive source and
CR motor control signal E1036 from IC E1006
Generates a CR motor drive signal E1037 according to
The R motor E0001 is driven. E1009 is LF / P
A G motor driver that uses a motor power supply E1040 as a drive source, generates an LF motor drive signal E1035 according to a pulse motor control signal (PM control signal) E1033 from the ASIC E1006, and thereby drives the LF motor and the PG motor A drive signal E1034 is generated to drive the PG motor.

E1010 is a power supply control circuit,
In accordance with a power control signal E1024 from CE1006, power supply to each sensor having a light emitting element is controlled.
Parallel I / F E0016 is ASIC E1006
I / F signal E1030 is transmitted to an externally connected parallel I / F cable E1031, and the signal of the parallel I / F cable E1031 is transmitted to an ASIC.
It transmits to E1006. Serial I / F E0017
Is the serial I / F signal E from the ASIC E1006.
1028 is transmitted to the serial I / F cable E1029 connected to the outside, and the signal from the cable E1029 is transmitted to the ASIC E1006.

On the other hand, from the power supply unit E0015, the head power supply (VH) E1039 and the motor power supply (VM) E
1040, a logic power supply (VDD) E1041 is supplied. Also, the head power supply O from the ASIC E1006
An N signal (VHON) E1022 and a motor power supply ON signal (VMOM) E1023 are input to the power supply unit E0015, and control ON / OFF of the head power supply E1039 and the motor power supply E1040, respectively. Power supply unit E
Logic power supply (VDD) E10 supplied from 0015
41 is a main PC after voltage conversion as necessary.
It is supplied to each part inside and outside BE0014.

The head power signal E1039 is sent to the flexible flat cable E0011 after being smoothed on the main PCB E0014, and is used for driving the recording head cartridge H1000. E100
Reference numeral 7 denotes a reset circuit which detects a drop in the logic power supply voltage E1041 and detects the CPU E1001 and the ASIC E1.
A reset signal (RESET) E1015 is supplied to 006 to perform initialization.

The ASIC E1006 is a one-chip semiconductor integrated circuit.
It is controlled by the U E1001 and outputs the above-mentioned CR motor control signal E1036, PM control signal E1033, power control signal E1024, head power ON signal E1022, motor power ON signal E1023, etc., and outputs the parallel I / F E0016 and serial I / F. F E0017
, A PE detection signal (PES) E1025 from the PE sensor E0007, an ASF sensor E
ASF detection signal (ASFS) E102 from 0009
6. The state of the GAP detection signal (GAPS) E1027 from the sensor (GAP) sensor E0008 for detecting the gap between the recording head and the recording medium and the PG detection signal (PGS) E1032 from the PG sensor E0010 are detected. Data indicating the state is transmitted to the CPU E1001 via the control bus E1014, and based on the input data, the CPU E1001 controls the driving of the LED driving signal E1038 to blink the LEDE0020.

Further, the encoder signal (ENC) E10
20 is detected to generate a timing signal, and the printhead cartridge H100 is generated by the head control signal E1021.
The interface with 0 controls the recording operation. Here, the encoder signal (ENC) E1020 is an output signal of the CR encoder sensor E0004 input through the flexible flat cable E0012. The head control signal E1021 is transmitted to the flexible flat cable E0012 and the carriage board E001.
3 and a contact FPC E0011 to the print head H1000.

FIG. 13 is a block diagram showing an example of the internal configuration of the ASIC E1006.

In the figure, the connection between the blocks shows only the flow of data related to the control of the head and the mechanical components such as recording data and motor control data, and the registers built in each block. Control signals and clocks related to reading and writing of the data, control signals related to DMA control, and the like are omitted to avoid complication in the drawings.

Referring to FIG. 13, reference numeral E2002 denotes a PLL controller. As shown in FIG. 13, the ASIC E1 is controlled by a clock signal (CLK) E2031 and a PLL control signal (PLLON) E2033 output from the CPU E1001.
Clock supplied to most of 006 (not shown)
Occurs.

E2001 is a CPU interface (CPU I / F), and a reset signal E1015,
Soft reset signal (PDWN) E2032 and clock signal (CLK) E2 output from CPU E1001
031 and a control signal from the control bus E1014,
Control of register read / write for each block as described below, supply of a clock to some blocks, acceptance of an interrupt signal, etc. (all not shown) are performed, and an interrupt signal (IN) is sent to the CPU E1001.
T) Output E2034 to notify the occurrence of an interrupt in ASIC E1006.

E2005 is a DRAM, and as a data buffer for recording, a reception buffer E2010,
Work buffer E2011, print buffer E201
4. It has various areas such as a data buffer E2016 for development and a motor control buffer E for motor control.
2023, and as a buffer used in the scanner operation mode, a scanner capture buffer E2024, a scanner data buffer E2026, and a transmission buffer E20 used in place of the recording data buffers described above.
28.

The DRAM E2005 has a CP
It is also used as a work area necessary for the operation of the EU 1001. That is, E2004 is a DRAM control unit, which is provided from the CPU E1001 by the control bus to the DRAM control unit.
Access to E2005 and DMA control unit E described later
Switching from access to the DRAM E2005 from 2003 is performed to perform a read / write operation to the DRAM E2005.

The DMA control unit E2003 receives a request (not shown) from each block, and receives an address signal and a control signal (not shown), and in the case of a write operation, write data E2038, E2041, E2044, and E2.
053, E2055, E2057 and the like are output to the DRAM control unit E2004 to perform DRAM access. In the case of reading, read data E2040, E2043, E2045,
E2051, E2054, E2056, E2058, E
2059 is passed to the requesting block.

Further, E2006 is IEEE 1284
I / F, CP via CPU I / F E2001
Under the control of U E1001, the parallel I / F E00
In addition to performing a two-way communication interface with an external host device (not shown) through
The received data (PIF received data E2036) from / FE0016 is subjected to DMA processing to receive control unit E200
8 and the DRAM E when reading the scanner.
The data (1284 transmission data (RDPIF) E2059) stored in the transmission buffer E2028 in 2005 is transmitted to the parallel I / F by DMA processing.

E2007 is a universal serial bus (USB) I / F. The serial I / F is controlled by the CPU E1001 via the CPU I / F E2001.
In addition to performing a two-way communication interface with an external host device (not shown) through the FE0017, the reception control unit E (USB reception data E2037) from the serial I / FE 0017 is subjected to DMA processing during printing during printing.
Delivered to 2008, DRAM when scanning
Data (USB transmission data (RDUSB) E2058) stored in the transmission buffer E2028 in E2005
Is transmitted to the serial I / F E0017 by the DMA processing. The reception control unit E2008 has a 1284 I / F E2
006 or received data (WDIF) E203 from the selected I / F of the USB I / F E2007
8) is written to the reception buffer write address managed by the reception buffer control unit E2039. E2009 is a compression / decompression DMA controller, which is a CPU I / F E2
Under the control of the CPU E1001 via 001, the reception data (raster data) stored in the reception buffer E2010 is read from the reception buffer read address managed by the reception buffer control unit E2039, and the data (RDWK) E2040 is designated. The data is compressed and decompressed according to the mode, and written in the work buffer area as a recording code string (WDWK) E2041.

Reference numeral E2013 denotes a recording buffer transfer DMA controller which controls the CPU via the CPU I / F E2001.
Work buffer E2011 under the control of E1007
The upper recording code (RDWP) E2043 is read out, and each recording code is stored in a print buffer E20 suitable for the data transfer order to the recording head cartridge H1000.
14 (WDWP E20)
44). Reference numeral E2012 denotes a work clear DMA controller, which controls the recording buffer transfer D under the control of the CPU E1001 via the CPU I / F E2001.
The designated work fill data (WDWF) E2042 is repeatedly written into the area on the work buffer to which the transfer by the MA controller E2013 has been completed.

Reference numeral E2015 denotes a print data expansion DMA controller, which controls the CP via the CPU I / F E2001.
The head control unit E2018 is controlled by the control of U E1001.
Triggered by the data development timing signal E2050 from the CPU, the recording code rearranged and written on the print buffer and the development data written on the development data buffer E2016 are read, and the development record data (RDH) is read.
DG) E2045 is stored in column buffer write data (WD
HDG) Write to the column buffer E2017 as E2047. Here, the column buffer E2017 is an SRAM for temporarily storing transfer data (developed recording data) to the recording head cartridge H1000, and includes a recording data developing DMA controller E2015 and a head controller E2015.
Shared management is performed by both blocks by a handshake signal (not shown) with 2018.

E2018 is a head control unit, which is a CPU I /
Under the control of the CPU E1001 via the FE2001, the recording head cartridge H is controlled via a head control signal.
1000 or the interface with the scanner, and based on the head drive timing signal E2049 from the encoder signal processing unit E2019, the print data development D
Data expansion timing signal E to MA controller
2050 is output.

At the time of printing, in accordance with the head drive timing signal E2049, the development print data (RDHD) E2048 is read from the column buffer, and the data is output to the print head cartridge H1000 as a head control signal E1021.

In the scanner reading mode, the fetched data (WDHD) E2053 input as the head control signal E1021 is transferred to the DRAM E2005.
The data is DMA-transferred to the upper scanner fetch buffer E2024. E2025 is a scanner data processing DMA controller, which is a CPU via a CPU I / F E2001.
The scanner capture buffer E2 is controlled by the control of E1001.
024 stored in the capture buffer (R
DAV) E2054 is read, and processed data (WDAV) E2055, which has been subjected to averaging and the like, is transferred to a DRAM.
Write to the scanner data buffer E2026 on E2005.

Reference numeral E2027 denotes a scanner data compression DMA controller, which is a CP via the CPU I / F E2001.
Under the control of UE1001, the processed data (RDYC) E2056 on the scanner data buffer E2026 is read out and data compression is performed, and the compressed data (WDY) is read out.
C) Write and transfer E2057 to the sending buffer E2028.

Reference numeral E2019 denotes an encoder signal processing unit which receives an encoder signal (ENC) and receives a signal from the CPU E1.
In addition to outputting the head drive timing signal E2049 in accordance with the mode determined by the control of 001, information relating to the position and speed of the carriage M4001 obtained from the encoder signal E1020 is stored in a register.
1001. The CPU E1001 determines various parameters in controlling the CR motor E0001 based on this information. E2020 denotes a CR motor control unit, which is a CPU via a CPU I / F E2001.
By the control of E1001, the CR motor control signal E103
6 is output.

Reference numeral E2022 denotes a sensor signal processing unit, which includes detection signals E1033, E1025, E1026, and the like output from the PG sensor E0010, the PE sensor E0007, the ASF sensor E0009, the GAP sensor E0008, and the like.
In response to E1027, the sensor information is transmitted to CPUE101 in accordance with the mode determined by the control of CPUE1001.
01 and a sensor detection signal E205 to the LF / PG motor control DMA controller E2021.
2 is output.

The LF / PG motor control DMA controller E2021 is controlled by the CPU I / F E2001
The DRAM E2005 is controlled by the PU E1001.
In addition to reading the pulse motor drive table (RDPM) E2051 from the upper motor control buffer E2023 and outputting the pulse motor control signal E1033, depending on the operation mode, the pulse motor control signal E1033 is output using the sensor detection signal as a control trigger.

E2030 is an LED control unit,
CPU E1001 via CPU I / F E2001
, An LED drive signal E1038 is output.
Further, E2029 is a port control unit, and CPUI /
Under the control of the CPU E1001 via the FE2001, a head power ON signal E1022, a motor power ON signal E1023, and a power control signal E1024 are output.

[Operation of Printer] Next, the operation of the ink jet recording apparatus according to the embodiment of the present invention configured as described above will be described with reference to the flowchart of FIG.

When the apparatus main body 1000 is connected to the AC power supply, first, in step S1, first initialization processing of the apparatus is performed. In this initialization process, the ROM and R
Check the electric circuit system such as AM check,
Electrically confirm that the device can operate normally.

Next, in step S2, the apparatus main body M100
0 power key E001 provided on the upper case M1002.
8 is turned on, and the power key E00
If the button 18 has been pressed, the process moves to the next step S3, where a second initialization process is performed.

In the second initialization process, various drive mechanisms and the recording head of the apparatus are checked. That is, when the various motors are initialized and the head information is read, it is confirmed whether the apparatus can operate normally.

Next, in step S4, an event is waited. That is, the apparatus monitors command events from the external I / F, panel key events due to user operations, internal control events, and the like, and executes a process corresponding to the event when these events occur.

For example, if a print command event is received from the external I / F in step S4, the process proceeds to step S5, and if a power key event is generated by a user operation in the same step, the process proceeds to step S10. The process proceeds to step S11 when another event occurs in the same step.

In step S5, a print command from the external I / F is analyzed to determine the designated paper type, paper size, print quality, paper feeding method, and the like. Stored in the RAM E2005 in the device,
Proceed to step S6.

Next, in step S6, paper feeding is started by the paper feeding method specified in step S5, the paper is fed to the recording start position, and the flow advances to step S7.

At step S7, a recording operation is performed. In this recording operation, the recording data sent from the external I / F is temporarily stored in the recording buffer, and then the CR motor E
0001 to start moving the carriage M4001 in the main scanning direction, and print buffer E201.
4 is stored in the print head H1001.
The LF motor E0002 is driven, the LF roller M3001 is rotated, and the sheet is fed in the sub-scanning direction. Thereafter, the above operation is repeatedly performed, and when the recording of one page of recording data from the external I / F is completed, the process proceeds to step S8.

In step S8, the LF motor E0002
Is driven to drive the paper discharge roller M2003, and the paper feeding is repeated until it is determined that the paper is completely fed out of the apparatus. When the paper is completely discharged, the paper is completely discharged onto the paper discharge tray M1004a. Becomes

Next, in step S9, it is determined whether or not the recording operation of all the pages to be recorded has been completed. If the pages to be recorded remain, the process returns to step S5. The operations from S5 to S9 are repeated,
When the recording operation of all pages to be recorded is completed, the recording operation ends, and thereafter, the process shifts to step S4 to wait for the next event.

On the other hand, in step S10, a printer termination process is performed to stop the operation of the present apparatus. That is, in order to turn off the power of various motors and heads, the state is shifted to a state where the power can be turned off, and then the power is turned off and step S4
Go to and wait for the next event.

In step S11, other event processing other than the above is performed. For example, a process corresponding to a recovery command from various panel keys or an external I / F of the apparatus or a recovery event generated internally is performed. After the process is completed, the process proceeds to step S4 and waits for the next event.

[0091] One mode in which the present invention is effectively used is a mode in which film boiling occurs in a liquid using thermal energy generated by an electrothermal converter to form bubbles.

[Embodiment] An ink jet recording head applied to a recording apparatus having the above-described configuration will be described.
In this embodiment, by forming a spacer having an arbitrary height (also referred to as “thickness”), electrical connection can be ensured.

Hereinafter, this embodiment will be described with reference to FIGS. 1 (a) to 1 (j).

First, as shown in FIG. 1A, an electrothermal conversion element 2 (a heater made of a material HfB2) as an element for generating energy used for ejecting ink and its surroundings, for example, an electric wiring board H1300, On a substrate 1 on which an aluminum pad 9 as an electrode for electrical connection is disposed, a polymethylisopropenyl ketone (Oh manufactured by Tokyo Ohka Kogyo Co., Ltd.) is used as a dissolvable resin layer (type resist layer) 3.
DUR-1010) to form an ink flow path pattern (FIG. 1B, film thickness 13 μm).

Then, as a first photosensitive coating resin material, a resin composition A shown in Table 1 was applied on the ink flow path pattern by a spin coater to form a first photosensitive coating resin layer 4 and a hot plate was used. Perform baking at ℃ 5 minutes (Fig. 1
(C), film thickness 18 μm).

Next, as shown in FIG. 1D, only the spacer portion 13 is exposed, and the resin composition A shown in Table 1 is again applied on the first photosensitive coating resin layer 4 already formed by a spin coater. Further coating is performed to form a first photosensitive coating resin layer 4 having a predetermined thickness, and baking is performed on a hot plate at 80 ° C. for 5 minutes (FIG. 1E, total film thickness: 40 μm).

[0097]

[Table 1]

Next, a resin composition B shown in Table 2 was applied on a PET film and dried to form a dry film (the PET film was removed), and a thermal pressure was applied on the resin composition A. Laminated, second photosensitive coating resin layer 5
Is formed (FIG. 1F, film thickness 0.5 μm).

For example, a mask aligner MPA600 manufactured by Canon Inc. is applied to the first and second photosensitive coating resin layers 4 and 5 formed as described above via a mask (not shown) in which discharge ports are formed. To perform 3 × 10 ⁴ W / m ² exposure. Then, after baking at 80 ° C for 5 minutes on a hot plate,
Development is performed with a developer of MIBK / xylene = 2/3, rinsed with xylene, and a position opposite to and above a heater which is an element for generating energy used for discharging ink as in the conventional example. The ink discharge ports 6 are formed in the photosensitive coating resin layer of (1), and at the same time, the spacers 13 having the same thickness as the bumps are formed (FIG. 1G).

Next, an ink supply port 8 is formed from the back surface of the Si wafer of the base 1 by anisotropic etching (FIG. 1 (h)). Subsequently, the mold resist layer 3 is removed, and the first resist layer 3 is removed.
And 2 to completely cure the second photosensitive coating resin layer.
A heat treatment is performed at 00 ° C. for 1 hour (FIG. 1 (i)). Finally, an electrical connection is made between the ACF 11 as a conductive sheet and the electrode 9 (FIG. 1 (j)), and an ink jet recording head is completed together with an ink supply member and the like.

The ink jet recording head manufactured as described above is mounted on the recording apparatus (printer) as described above, and pure water / diethylene glycol / isopropyl alcohol / lithium acetate / black dye food black 2 = 7
When recording was performed using the ink composed of 9.4 / 15/3 / 0.1 / 2.5, stable printing was possible.
The obtained image was of high quality.

[0102]

[Table 2]

(Comparative Example 1) Using a conventional technique, a first photosensitive material was formed by a single application of the first photosensitive material to form a 40 μm thick first photosensitive coating resin layer as in the example, to obtain an ink jet recording head. .

A printing test was performed in the same manner as in the example. As a result, a portion where the spacer was too high and conduction was not obtained by the conductive sheet was recognized, and accurate printing was not performed.

Further, since the first photosensitive material was applied at a time of 40 μm at a time, the distance between the heater, which is an element for generating energy used for ejecting ink, and the ink ejection port varies, and the ink ejection control Affecting the quality of the image.

(Comparative Example 2) As shown in FIG.
The first application of the photosensitive material is performed at a film thickness of 18 μm, and then, as shown in FIG. 1D, until the exposure of the spacer portion is performed in the same manner as in the example. First, it is formed.

Thereafter, the first photosensitive material was again applied twice so as to have a total film thickness of 40 μm in the same manner as in the example to obtain an ink jet recording head.

As a result of performing the same printing test as in the embodiment,
Stable printing was possible, there was no variation in the distance between the heater and the ink ejection orifice, the image was of high quality, and an ink jet recording head having the same performance as that of the example was obtained.
However, the number of manufacturing steps increases, the amount of materials used increases, and the method is not economical.

The ink jet recording head and the method of manufacturing the same according to the present invention have been described above. The present invention is not limited to this, and may be any as long as it is within the scope of the present invention.

[0110]

According to the present invention, since the distance and positional accuracy between the element for generating energy used for discharging ink and the ink discharge port can be strictly controlled, the discharge characteristics are stabilized, and A highly reliable inkjet recording head can be manufactured by a simple method.

In connection with the conductive sheet, the spacer without the water-repellent layer can be formed at an arbitrary height by changing the amount of application or the number of application of the photosensitive coating resin material, and the reliability of the electrical connection can be improved. The properties have also been significantly improved. further,
Since the height of the spacer can be set low, complete sealing can be performed with a small amount of sealing material.

[Brief description of the drawings]

FIG. 1 is a schematic view showing a manufacturing process of an ink jet recording head according to the present invention. FIG. 1 (a) is a cross-sectional view of a base on which predetermined wirings including electrodes and the like are arranged.
(B) is a state in which a mold resist is applied on a substrate,
(C) is a state in which the first photosensitive coating resin material is once applied on the mold resist, (d) is a state in which the spacer portion is exposed through a mask, and (e) is a first photosensitive coating resin material. Is further applied, (f) is a state in which the second photosensitive coating resin material is applied, (g) is a state in which an ink discharge port, a spacer, etc. are formed by exposure and development, and (h) ink The state in which the supply port is formed, the state in which (i) the resist is removed, and the state in which (j) is the state in which the conductive sheet and the electrode are connected, respectively.

FIGS. 2A and 2B are schematic views showing a manufacturing process of a conventional ink jet recording head, particularly, a nozzle portion thereof. FIG. 2A is a perspective view of a base on which an element for generating energy used for discharging ink is arranged. (B) is a cross-sectional view of (A) in FIG. AA, (c) is a state in which a mold resist is applied on a substrate, (d) is a state in which a first photosensitive coating resin material is applied, (e) ) Is a state in which the second photosensitive coating resin material is applied, (f) is a state in which an ink discharge port and a hydrophilic portion are formed by exposure and development processing, and (g) is a state in which an ink supply port is formed. (H) shows a state in which the mold resist has been removed.

3A and 3B are diagrams showing an electrical connection between a conventional printing element substrate and surrounding conductors through conductors, wherein FIG. 3A is a cross-sectional view of the printing element substrate manufactured in FIG. 2, and FIG. Is a state in which bumps are formed on the electrodes, (c) is a state in which the conductive sheet is
(D) is a state in which the conductive sheet is connected to the bump by applying thermal pressure, and (e) is a state in which the conductive sheet is positioned on the bump.
Indicates a state in which a sealing material is applied to the connection portion.

FIG. 4 is a view in which a spacer is further provided in the electrical connection between the conventional printing element substrate of FIG. 3 and a conductor around the printing element substrate.

FIG. 5 is a perspective view showing an external configuration of an example of an ink jet printer to which the ink jet recording head of the present invention is applied.

FIG. 6 is a perspective view showing a state where an exterior member of the printer shown in FIG. 5 is removed.

FIG. 7 is a perspective view showing an assembled state of a recording head cartridge used in a printer to which the ink jet recording head of the present invention is applied.

8 is an exploded perspective view showing the recording head cartridge shown in FIG.

FIG. 9 is an exploded perspective view of the recording head shown in FIG. 8 as viewed obliquely from below.

10A and 10B are perspective views showing a configuration of a scanner which can be purchased in the printer and can be purchased in the recording head cartridge of FIG. 7, in which FIG. 10A is a perspective view of the scanner in a normal arrangement, and FIG. , (A) is a perspective view in which the top and bottom are reversed.

FIG. 11 is a block diagram schematically showing an overall configuration of an electric circuit in a printer to which the inkjet recording head of the invention is applied.

FIG. 12 is a main PCB of the electric circuit shown in FIG. 11;
3 is a block diagram showing an example of the internal structure of FIG.

FIG. 13 is an ASIC of the main PCB shown in FIG. 12;
3 is a block diagram showing an example of the internal structure of FIG.

FIG. 14 is a flowchart illustrating an operation example in a printer to which the inkjet recording head of the present invention is applied.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Substrate 2 Element (heater) which generates energy used for discharging ink 3 type register 4 First photosensitive covering resin layer 5 Second photosensitive covering resin layer 6 Ink ejection port 8 Ink supply port 9 Electrode 11 Conduction Sheet 13 Spacer 14 Nozzle section H1000 Printhead cartridge H1001 Printhead H1100 Printing element substrate H1100T Discharge port H1200 First plate H1201 Ink supply port H1300 Electric wiring board H1301 External signal input terminal H1400 Second plate H1500 Tank holder H1501 Ink flow path H1600 Flow path forming member H1700 Filter H1800 Seal rubber H1900 Ink tank 100 Main body EEPROM 200 Head EEPROM HOST Host device

Claims (15)

[Claims] A nozzle unit having at least an ink discharge port for discharging ink and an ink flow path communicating with the ink discharge port; an element for generating energy used for discharging the ink; A print element substrate having: and a wiring board electrically connected to the print element substrate, wherein the print element substrate has the nozzle near the electrode electrically connected to the wiring board. An ink jet recording head comprising a spacer formed of the same material as the ink jet head and having a height lower than a height of an ink discharge port forming surface in the nozzle. 2. The ink jet recording head according to claim 1, wherein said element is disposed on a base of said recording element substrate. 3. The ink jet recording head according to claim 1, wherein the discharge port extends in a direction perpendicular to the substrate at a position facing the element with an ink flow path interposed therebetween. 4. The ink jet recording head according to claim 1, wherein said ink flow path extends along said base. 5. The ink jet recording head according to claim 1, wherein the nozzle portion is formed of at least two photosensitive coating resin layers. 6. The ink jet recording head according to claim 5, wherein the uppermost layer of the photosensitive coating resin is a water-repellent layer. 7. The ink jet recording head according to claim 1, wherein said wiring substrate and said electrode are electrically connected by an anisotropic conductive sheet. 8. A nozzle portion having at least an ink ejection port for ejecting ink and an ink flow path communicating with the ink ejection port, an element for generating energy used for ejecting the ink, In a method for manufacturing an ink jet print head, comprising: a printing element substrate having: a wiring substrate electrically connected to the printing element substrate; and forming an electrode and the element electrically connected to the wiring substrate on a base. Forming an ink flow path pattern with a dissolvable resin on a substrate having the elements and electrodes; and forming a photosensitive coating resin layer serving as an ink flow path wall on the ink flow path pattern. Forming a plurality of photosensitive coating resin layers by coating at least twice, and exposing after the application of the intermediate layer and the application of the final layer to form a spacer having an arbitrary height. Degree and, on the photosensitive coating resin layer of the opposite position and the device, forming an ink discharge port, the manufacturing method of the ink jet recording head and a step of eluting the soluble resin. 9. A water-repellent photosensitive coating resin material is further applied on a plurality of photosensitive coating resin layers formed by applying the photosensitive coating resin layer two or more times.
9. The method according to claim 8, further comprising the step of forming the photosensitive coating resin layer. 10. A plurality of photosensitive coating resin layers formed by applying the photosensitive coating resin layer two or more times to form a solution in which a resin containing a solid epoxy resin is dissolved in a solvent at room temperature. 9. The semiconductor device according to claim 8, wherein
Or a method for manufacturing an ink jet recording head according to item 9. 11. A plurality of photosensitive coating resin layers formed by applying the photosensitive coating resin layer two or more times are formed by a spin coating method. The manufacturing method of the ink jet recording head according to the above. 12. The ink jet recording head according to claim 9, wherein the second photosensitive coating resin layer is formed of a solution obtained by dissolving a resin containing a fluorine-containing epoxy resin in a solvent. Manufacturing method. 13. A plurality of photosensitive coating resin layers formed by applying the photosensitive coating resin layer twice or more, wherein the second photosensitive coating resin layer is formed in advance as a dry film. 13. The method for manufacturing an ink jet recording head according to claim 9, wherein the ink jet recording head is laminated. 14. The method according to claim 8, wherein the height of the spacer is lower than a height of an ink discharge port. 15. The method according to claim 8, wherein the wiring substrate and the electrode are electrically connected by an anisotropic conductive sheet.