JPH0985951A - Ink-jet recording head and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ink-jet recording head and the manufacture thereof which can ensure the highly accurate positioning of liquid passages in the process of boring ink discharge ports for the liquid passages and in the process of mounting a recording head on a base. SOLUTION: In a recording head wherein dummy liquid passages 5E, 5D provided in parallel with true liquid passages 5 and on both sides of rows thereof are formed into a groove shape as a pattern and connected to a heater board, the ones 5E among the dummy liquid passages 5E, 5D are made to have a cross-sectional shape different from those of the liquid passages 5, 5D for at least each one on both the sides of the rows of the true liquid passages 5.

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 and a method of manufacturing the same, and more specifically, an ink liquid passage and an ink ejection port are arranged corresponding to a plurality of electrothermal converters formed on a heater board. The present invention relates to an inkjet recording head and a manufacturing method thereof.

[0002]

2. Description of the Related Art In recent years, an electrothermal converter (hereinafter referred to as a heater) provided for each liquid path is selectively driven to heat ink that is in contact with the heater to cause foaming, and the pressure change due to the foaming is utilized. A so-called bubble jet type recording head has been developed and put into practical use, in which ink is ejected from an ejection port and recording is performed on a recording material (hereinafter referred to as a recording sheet).

In assembling a bubble-jet type recording head of this type, a heater for heating ink and an ejection port for ejecting the film-boiling ink heated by the heater toward a recording sheet are used. , Must be accurately positioned on the order of microns or less. That is, it is necessary to accurately position and assemble the heater board on which a large number of heaters are formed and the top plate including the orifice plate on which a large number of ink ejection openings are formed, at fixed relative positions. For example, in order to achieve a high recording accuracy of about 360 dpi (dotts per inch), it is necessary to arrange 64 ejection ports at equal intervals within a range of about 4.5 mm. The pitch has a fine value of about 70 μm.

To form the ink ejection openings at such minute intervals, for example, by using an ultra-precision processing device such as a laser processing device, a predetermined allowable amount is set in the orifice plate provided on the front surface of the top plate. It is possible to form the discharge port with high accuracy. Regarding the formation of the heater,
Fine processing can be performed by using the same film forming technique and photolithography technique as those used in the semiconductor manufacturing process.

Under these circumstances, therefore, the process for assembling the bubble jet recording head is roughly divided into two, that is, the processing of the heater board and the processing of the top plate, and the finished products in each step are combined. I am trying to do it.

First, regarding the processing of the above-mentioned top plate, the outer shape, the structure and the like are precisely formed by using a molding processing technique such as injection molding. It is arranged on a pallet and sent to the next process. In addition, as the structure of the top plate, as described above, a large number of partition walls for ink liquid paths are formed in a slit shape at a fine pitch. In the perforation process, the ink liquid path and the perforation position on the orifice plate side are aligned by image processing and then precisely processed by laser irradiation.

Further, the formation of the partition for the ink liquid path is carried out by an injection molding die. Such a die is made by a precision die processing technique, but it is possible to form a fine pitch with a precise pitch. In order to form the ink liquid passages, more ink liquid passages than originally necessary are formed, and the processing conditions are set by what is called an extra dummy ink liquid passage, while the original ink liquid passages are set. In this case, it is necessary to finish to the desired accuracy.

FIG. 6 shows an example of the construction of an ink jet cartridge 100 in which the recording head and the ink tank having the above-mentioned configuration are integrally formed and which is detachably attached to the recording apparatus side. Here, 101 is an inkjet cartridge 10
An ink jet recording head unit incorporated in 0, an ink tank unit 102 for containing ink to be supplied to the recording head unit 101, an orifice plate 103 provided in the recording head unit 101, and an orifice plate 103. A plurality of ink ejection openings are formed in the. The inkjet recording head unit 101 is positioned and fixed on the substrate 111 as shown in FIGS. 7 (A) and 7 (B).

Further, in FIG. 7, 106 is a heater board which is a component of the recording head section 101, 107 is a top plate, and 108 is an ink supply port for supplying ink to a liquid chamber (not shown). A plurality of heaters 109 are arranged on the heater board 106 as shown in (B). The ink discharge port 104 is formed in each liquid path (not shown) corresponding to the heater 109, and the orifice plate 103 and the top plate 107 are integrally formed as described above. Therefore, in the case of this example, the ink ejection port 104 is precisely formed by laser processing or the like in the orifice plate 103 integrated with the top plate 107.

Furthermore, as described above, the top plate having the liquid passage formed on the heater board is aligned, and the ink discharge port corresponding to the liquid passage is perforated on the orifice plate attached to the top plate. In addition to the ink jet recording head, a top plate on which a liquid passage and a liquid chamber are formed and a heater board are joined in a laminated manner, and an ink ejection port is formed at the end of the liquid passage. It has been known.

FIG. 8 shows an example of the construction of such an ink jet recording head 201, in which 204 is an ink ejection port, 205 is a liquid passage, 206 is a substrate, 207 is a top plate, 208 is a liquid chamber, 209. Is each liquid path 20 on the substrate 206.
5 is a heater.

[0012]

However, the conventional ink jet recording head as described above has the following problems in its manufacturing process.

That is, in the case of the ink jet recording head 101 having the configuration as shown in FIG. 7, accurate and high precision is achieved with respect to the fine grooves formed corresponding to each liquid passage of the molded top plate 107. Keep each ink ejection port 104
The perforation is performed by, for example, laser processing, but prior to the perforation, relative positioning between the ink ejection port 104 to be perforated and the corresponding liquid passage is necessary. Then, at the time of such positioning, the rows of liquid paths including the dummy liquid paths provided on the top plate 107 are photographed from both ends by a camera with an appropriate magnification, and this is observed on a television monitor. The partition wall portion, which is the boundary between the dummy liquid path and the true liquid path, is recognized by the image processing apparatus.

FIG. 9 shows the form of such a conventional liquid passage for recognition and a partition wall between them, where 10
5A is a groove serving as a true liquid path, 105D is a groove serving as a dummy liquid path, and 110 is a partition wall between these grooves 105A and 105D. Therefore, in the conventional case, even if the grooves 105A and 105D as shown in FIG. 9 are observed, the cross-sectional shape does not change and the shape of the partition wall 110 does not change, so that it is erroneously recognized and the positioning is slightly deviated. It happened.

Furthermore, when a recording head having a higher dpi or a color ink jet recording head, in particular, a different ink is ejected for each recording head and color recording is realized by the arrangement of such recording heads. In the case where one ejection head array for ejecting different inks is arranged by one recording head, the corresponding ejection opening positions must always be maintained accurately even if they are replaced. Assembly adjustment by positioning of is required.

Further, whether the ink jet recording head 101 of the form shown in FIG. 7 or the ink jet recording head 201 of the form shown in FIG. 8 has a problem in the step of positioning it on the substrate, the accuracy is maintained in this positioning step. If this is not the case, color misregistration will occur especially in the case of color recording by arranging a plurality of recording heads in parallel.

Up to now, as shown in FIG. 10, for example, when positioning the ink jet recording head 201 shown in FIG. 10A on the substrate 211 shown in FIG. The reference pin 210 is provided upright and positioned so that the ink ejection port surface 201A and the reference surface 201B of the recording head 201 and the reference surfaces 211A and 211B of the base body 211 are abutted against the reference pin 210, respectively, and an adhesive is applied between them. And so on.

However, in such a positioning method, the accuracy produced when the outer circumference of the recording head 201 itself is cut is ± 20.
There is a variation of about μm, and in mechanical positioning, there is a limit to the positioning accuracy that can be obtained, leading to a reduction in product yield.

An object of the present invention is to achieve accurate positioning in the process of punching an ink ejection port corresponding to a liquid path by an image processing device or the like in order to solve the above-mentioned problems in manufacturing a recording head. Another object of the present invention is to provide an ink jet recording head having high quality and high reliability, which enables highly accurate positioning even in the step of mounting the recording head on the substrate, and a manufacturing method thereof.

[0020]

In order to achieve such an object, a first mode of an ink jet recording head according to the present invention is a heater board having a plurality of heaters for generating ink ejection energy, and ejecting ink. And a plurality of true liquid paths through which the ink is guided and dummy liquid paths, which are arranged in parallel on both sides of the plurality of true liquid paths and are not guided by ink, are formed in a groove shape as a pattern, and from the true liquid paths An ink jet recording head to be joined to a top plate member having an orifice plate having an ink discharge port formed therein, wherein liquid channels formed in the groove are provided on both sides of the plurality of true liquid channels. It is characterized in that at least one of the dummy liquid passages arranged in parallel is made different from the cross-sectional shape of the other liquid passages.

In the method for manufacturing an ink jet recording head according to the first aspect of the present invention, a heater board on which a plurality of heaters for generating ink ejection energy are formed, and a plurality of true liquids through which the ejected ink is guided. Channels and dummy liquid channels not guided by ink, which are arranged in parallel on both sides of the true liquid channels, are formed in a groove shape as a pattern, and ink discharge ports are formed from the true liquid channels. A method of manufacturing an ink jet recording head, which is joined to a top plate member having an orifice plate, wherein positioning of the top plate member with respect to a boring means is performed when the ink ejection port is bored in the orifice plate. A pattern in which at least one of the dummy liquid passages arranged in parallel on both sides of the true liquid passage among the liquid passages formed in a different shape is different from the cross-sectional shape of the other liquid passages. It is characterized in that performed by identification.

Furthermore, in the second aspect of the ink jet recording head of the present invention, a plurality of true ink ejection ports for ejecting ink and a dummy which is juxtaposed on both sides of the plurality of true ink ejection ports and does not eject ink. In the ink jet recording head having the other ink ejection ports, at least one dummy ink ejection port has a different shape from the other ink ejection ports on both sides of the plurality of true ink ejection ports. It is what

Further, in the method for manufacturing an ink jet recording head according to the second aspect of the present invention, a plurality of true ink ejection ports for ejecting ink and inks arranged in parallel on both sides of the plurality of true ink ejection ports are provided. When positioning an inkjet recording head having a dummy ink ejection port that does not eject on a substrate, the shape recognition of a dummy ink ejection port is made different from the shapes of other ink ejection ports on both sides of the plurality of true ink ejection ports. Is used.

According to the first aspect of the present invention, at least one of the dummy liquid passages provided on both sides of the plurality of true liquid passages is provided.
By making each one different from the shape of the other liquid passages, the liquid passage pattern can be accurately and accurately recognized when positioning the top plate member when the ink discharge ports are formed in the orifice plate of the top plate member. It is possible to achieve highly accurate positioning.

Further, according to the second aspect of the present invention, at least one of the dummy ink ejection openings arranged in parallel on both sides of the plurality of true ink ejection openings is shaped as another ink ejection opening. When the inkjet recording head is positioned on the substrate, the shape recognition of the dummy ink ejection ports having the different shapes described above is incorporated to contribute to the improvement of the positioning accuracy.

[0026]

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

FIG. 1 shows the structure of a top plate member 7 according to the first embodiment of the present invention. The top plate member 7 shown here is in a state before being joined to the heater board. Therefore, the heater board is joined from above to the top plate member 7 in the posture shown in this figure. The below-described positioning of the ink discharge port 4 formed in the orifice plate 3 with respect to the liquid path 5 is performed in this state. 5D and 5E are both dummy liquid passages (5, 5D and 5E are all grooves for forming a liquid passage, but will be referred to as liquid passages hereinafter), and the dummy liquid passage 5E is related to the present invention. A liquid passage for positioning identification (hereinafter referred to as an identification dummy), 8 is a recess for forming a common liquid chamber (hereinafter referred to as a common liquid chamber), 9 is a peripheral wall, and 10 is a space between the liquid passages. Is a liquid passage partition.

2A and 2B show a cross section taken along the line AA of the top plate member 7 shown in FIG. As described above, the identification dummy liquid passage 5E provided for positioning is formed to have a shallower depth than the other true liquid passage 5 and the dummy liquid passage 5D, whereby the identification dummy liquid passage 5E is formed. 5E and other liquid paths 5
And 5D can be easily distinguished. In forming the identification dummy liquid passage 5E, for example, it is only necessary to reduce the depth of the groove processed as the identification dummy liquid passage 5E when manufacturing the precision die. By performing a molding process using an injection molding machine, a reproducible and highly accurate top plate member 7 can be obtained, and the identification dummy liquid passage 5E can be formed at the same predetermined location.

Next, the positioning for forming the ink discharge port 4 in the orifice plate 3 of the top plate member 7 shown in FIG. 1 and its forming operation will be described with reference to FIG. FIG. 3 schematically shows an outline of a laser drilling apparatus for punching ink ejection ports. Here, 300 is its laser light output device (main body), and 301, 302 and 303 are optical lens systems for converging the laser light output from the laser light output device 300 toward the orifice plate 3 of the top plate member 7. Reference numeral 304 denotes a mask in which the shape of the ink ejection openings 4 to be punched is formed as a pattern, and 305 is a support base that can be finely moved in the ejection opening arrangement direction with the top plate member 7 supported at a predetermined position. .

It should be noted that the support 305 is used as the image processing apparatus 30.
The signals from 6A and 306B make fine movements to perform the alignment described later. Also, 307A and 307
B is a CCD camera, 308A and 308B are reflectors,
Reference numerals 309A and 309B denote television monitors, and the television monitors 309A and 309B have CCD cameras 308.
The images from A and 308B are output according to the alignment operation. On the other hand, in the case of this example, at least the pattern of the identification dummy liquid passage 5E is stored in the image processing devices 306A and 306B. That is, the support 305,
Image processing devices 306A and 306B, CCD camera 307
A, 307B and the like are used to align the perforation position of the ink discharge port 4 on the orifice plate 3 of the top plate member 7 with the reduced pattern projected on the orifice plate 3 via the mask 304.

In the positioning and laser processing apparatus for forming the ink discharge port having such a configuration, C is used.
Through the CD cameras 307A and 307B, the support base 305 is moved based on the information related to the liquid path 5 and the dummy liquid path 5D, the identification dummy liquid path 5E, and the liquid path partition wall 10 obtained from the top plate member 7, and the predetermined position. The punching is performed by the laser light output from the laser light output device 300 at the punching position. Further, according to the present invention, since the identification dummy liquid passages 5E are provided at both ends of the above-mentioned perforation position, the identification patterns stored in the storage device and the above identification in the image processing apparatuses 306A and 306B are provided. When they coincide with the dummy liquid passages 5E, it can be determined that they are the limits of the ink ejection port forming regions.

Therefore, in the conventional image processing apparatus, since the dummy liquid path and the true liquid path have the same pattern, erroneous recognition during positioning is prevented. Thus, as shown in FIG. 2B, the identification dummy liquid passage 5 is provided.
The ink ejection port 4 can be formed at a position on the orifice plate 3 corresponding to each liquid path 5 between E.

In the above-described embodiment, only the identification dummy liquid passage 5E has a shallower groove than the other liquid passages 5, but the sectional shape of the identification dummy is not limited to this. Also, the position is not necessarily limited to the boundary between the true liquid path and the dummy liquid path, and the number thereof may be one or more instead of one. In short, any shape may be used as long as it is formed so that both ends of the true ink ejection port forming region are identified when performing the alignment for forming the ink ejection port.

Next, the positioning operation of the recording head according to the present invention on the substrate will be described.

An example of positioning the ink jet recording head 201 of the form shown in FIG. 8 on the substrate 211 will be described below. In the case of this example, the liquid path, the ink discharge port, the liquid path forming partition, and the like are formed on the top plate member 207 side. Therefore, in the ink jet recording head 201 of this embodiment, the ink discharge port is the substrate and the top plate member. Since it is formed by joining with the ink jet recording head 101 described above, there is no need for a step of forming an ink ejection port 104 in the orifice plate 103 in the manufacturing process thereof unlike the ink jet recording head 101 of the above-described form.

In the case of this example, as shown in FIG. 5, up to the formation of the corresponding ink discharge port at the time of forming the liquid passage to the top plate member is formed almost the same as the liquid passage. Although not shown in the drawing, the dummy liquid passage and the dummy ink discharge port of this example are previously closed at the portions communicating with the dummy liquid passage from the liquid chamber. In FIG. 5, 4D is a dummy ink ejection port formed in this way, and 4E is an identification dummy ejection port that functions similarly to the identification dummy liquid passage 5E in the above-described example. However, the identification dummy discharge port 4 in the case of this example
E is formed such that the opening width in the ink ejection port arrangement direction is wider than that of the true ink ejection port 4 and other dummy ejection ports 4D. Therefore, when positioning the recording head 201 on the substrate 211 as described below, highly accurate positioning is achieved by detecting the position of the identification dummy ejection port 4E.

4 and 5 show an embodiment in which the ink jet recording head 201 is positioned on the substrate 211. In this example, the positioning is performed by a laser displacement device. Lasers are known to be used as various length measuring machines and minute displacement gauges that project a laser beam toward an object to be measured and use the interference obtained from the reflected wave to perform high-precision length measurement and displacement measurement. These devices are used for fine positioning even in the semiconductor manufacturing process that requires high density.

In the present embodiment, first, the two sides of the base body 211 are abutted against the horizontally fixed base body abutting reference member 40, and the base body 211 is positioned by suction means or pressing means. On the other hand, the inkjet recording head 201 is held by a supporting unit (fine movement stage) (not shown) that is displaceable in the direction along the base 211. Further, 50 is a laser displacement meter capable of highly accurate distance measurement and position detection. In the case of this example, the laser displacement meter 5
0 is set at a position facing the ink ejection port surface 201A of the recording head 201. The laser displacement meter 50 stores the horizontal distance to the front end 211A of the base body 211 in a memory.

Therefore, as shown in FIG.
Laser light 51A is projected from 0 to the ink ejection port surface 201A, and reflected light 51B from the ink ejection port surface 201A is received by the laser displacement meter receiving unit 52 to measure the distance to the ink ejection port surface 201A. . Then, the position of the ink jet recording head 201 is finely adjusted so that the distance measuring distance matches the horizontal distance to the front end 211A of the base body stored in the laser displacement meter.
Positioning of No. 1 in the Y direction can be performed with high precision by the fine movement stage described above.

In this way, when the positioning of the recording head 201 in the Y direction is obtained, the ink ejection ports 4, 4E, 4D of the recording head ink ejection port surface 201A as shown in FIG.
The position of the recording head 201 in the X direction can be accurately determined by projecting light from the laser displacement meter 50 toward the target and detecting the position of the identification dummy ejection port 4E in the same procedure as described above.

Incidentally, in the above-mentioned positioning of the recording head with respect to the substrate, the laser displacement meter projects the laser beam toward the ink ejection port surface of the recording head, and the laser beam is received by the laser displacement meter. The direction of light reception and the positioning method performed based on it are not limited to the above, and any configuration and method may be used as long as the position is detected by detecting the position of an element related to the ink ejection port by laser light. It may be one.

[0042]

As described above, according to the present invention, a heater board in which a plurality of heaters for generating ink ejection energy are formed, a plurality of true liquid paths through which ejected ink is guided, and An orifice plate in which dummy liquid passages, which are not guided by ink, are formed in a groove shape as a pattern and arranged in parallel on both sides of a plurality of true liquid passages, and ink ejection ports are formed from the true liquid passages. An ink jet recording head to be joined to a top plate member having at least one of dummy liquid passages arranged in parallel on both sides of the plurality of true liquid passages among the groove-shaped liquid passages. Since each is made different from the cross-sectional shape of the other liquid path, the position of the ink ejection port can be positioned with high accuracy for each recording head, which facilitates adjustment in the assembly process after the recording head, Eliminates color misregistration due to misregistration of ink ejection ports in a plurality of recording heads arranged like a color printer and contributes to improving the quality of a color recording image, and omits a step for troublesome adjustment. It is possible to contribute to cost reduction.

Further, in the ink jet recording head having a plurality of true ink ejection openings for ejecting ink and dummy ink ejection openings for ejecting ink, which are arranged in parallel on both sides of the plurality of true ink ejection openings, Since the shape of each of the ink ejection ports is different from the shape of at least one of the other ink ejection ports on both sides of the plurality of true ink ejection ports, the ink jet recording head on the substrate has variations in individual dimensional accuracy. Regardless, positioning can always be performed with the same level of high precision.

[Brief description of drawings]

FIG. 1 is a perspective view showing a configuration example of a top plate member according to the present invention.

FIG. 2 is an explanatory view showing a state (A) in which an ink ejection port is formed and a state (B) in which an ink ejection port is punched, respectively, taken along the line AA in FIG.

FIG. 3 is a block diagram showing a configuration of a positioning device for a step of punching an ink ejection port on a top plate member by a laser according to the manufacturing method of the present invention.

FIG. 4 is an explanatory diagram showing the configuration of a positioning device for positioning a recording head on a substrate according to the manufacturing method of the present invention together with its operation.

FIG. 5 is an explanatory view showing the configuration of the positioning device for positioning the recording head on the substrate according to the manufacturing method of the present invention together with its operation.

FIG. 6 is a perspective view showing a configuration example of an inkjet cartridge.

7 is a perspective view showing an example of the configuration of an inkjet recording head incorporated into the inkjet cartridge shown in FIG. 6 by (A) and (B).

FIG. 8 is a perspective view showing a configuration example of an ink jet recording head of a different form from FIG.

9 is a cross-sectional view showing a configuration example of a conventional ink liquid path in the ink jet recording head of the form shown in FIG.

FIG. 10 is an explanatory view showing a conventional device for positioning a recording head on a substrate and its operation by (A), (B) and (C).

[Explanation of symbols]

 3 Orifice plate 4 Ink ejection port 4D Dummy ink ejection port 4E Identification dummy ejection port 5 Liquid path (groove for formation) 5D Dummy liquid path 5E Identification dummy liquid path 7 Top plate member 8 Common liquid chamber (recess) 9 Surroundings Wall 10 Liquid path partition 40 Abutting reference member 50 Laser displacement meter 51A Laser light 51B Laser reflected light 52 Light receiving part 101, 201 Inkjet recording head 106 Heater board 205 Substrate 109 Heater 211, 211 Base 201A Ink ejection port surface 300 Laser (light Output) device 304 mask 305 support 306A, 306B image processing device 307A, 307B CCD camera 309A, 309B TV monitor

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shuji Koyama 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Suzuki Kogaku, 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Incorporated (72) Inventor Hisashi Yamamoto 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Manabu Sueoka 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. ( 72) Inventor Makoto Shibata 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc.

Claims (9)

[Claims] 1. A heater board in which a plurality of heaters for generating ink ejection energy are formed, a plurality of true liquid passages through which ink to be ejected is guided, and a plurality of true liquid passages arranged in parallel on both sides of the true liquid passages. An ink jet recording head in which a dummy liquid path through which ink is not guided is formed in a groove shape as a pattern and is joined to a top plate member having an orifice plate in which an ink ejection port from the true liquid path is formed. Of the liquid paths formed in the groove, at least one of the dummy liquid paths arranged in parallel on both sides of the plurality of true liquid paths is made different from the cross-sectional shape of the other liquid paths. An inkjet recording head characterized in that 2. A heater board on which a plurality of heaters for generating ink ejection energy are formed, a plurality of true liquid passages through which the ejected ink is guided, and a plurality of true liquid passages arranged in parallel on both sides of the true liquid passages. An ink jet recording head in which a dummy liquid path through which ink is not guided is formed in a groove shape as a pattern and is joined to a top plate member having an orifice plate in which an ink ejection port from the true liquid path is formed. In the method of manufacturing the above-mentioned, when the ink discharge port is formed in the orifice plate, the positioning of the top plate member with respect to the forming means is performed.
At least one of the dummy liquid passages arranged in parallel on both sides of the true liquid passage among the groove-shaped liquid passages is performed by pattern recognition different from the cross-sectional shape of the other liquid passages. A method of manufacturing an inkjet recording head, comprising: 3. The method of manufacturing an ink jet recording head according to claim 2, wherein the ink ejection port is formed by laser processing means. 4. The method of manufacturing an inkjet recording head according to claim 2, wherein the top plate member is positioned with respect to the perforating means by using an image processing device. 5. An ink jet recording head having a plurality of true ink ejection ports for ejecting ink and dummy ink ejection ports arranged in parallel on both sides of the plurality of true ink ejection ports for ejecting no ink. The ink jet recording head is characterized in that at least one of the ink ejection ports has a shape different from that of the other ink ejection ports on both sides of the plurality of true ink ejection ports. 6. An ink jet recording head having a plurality of true ink ejection openings for ejecting ink and dummy ink ejection openings arranged in parallel on both sides of the plurality of true ink ejection openings for ejecting no ink on a substrate. A method for manufacturing an ink jet recording head, characterized in that, when performing positioning, shape recognition of dummy ink ejection openings different from the shapes of other ink ejection openings on both sides of the plurality of true ink ejection openings is used. 7. The method for manufacturing an ink jet recording head according to claim 6, wherein the shape of the dummy ink ejection port, which is different from the shape of the other ink ejection port, is recognized by a laser displacement meter. 8. The method of manufacturing an inkjet recording head according to claim 6, wherein the inkjet recording head is positioned on the substrate by using an image processing device. 9. The ink jet recording head according to claim 1 or 5, further comprising an electrothermal converter as a heater for generating ink ejection energy, and the electrothermal converter causes film boiling in the ink. An ink jet recording head, which discharges ink by utilizing a pressure change due to foaming.