KR20200096191A - Liquid ejection substrate, liquid ejection head, and liquid ejection apparatus - Google Patents

Abstract

A first passage layer is provided with a plurality of supply passages each communicating with a part of each of a plurality of pressure chambers, and a plurality of recovery passages each communicating with another part of each of the plurality of pressure chambers. A second passage layer is provided with a common supply passage communicating with the supply passages and a common recovery passage communicating with the recovery passages. According to the present invention, liquid can be circulated through the pressure chambers corresponding to respective outlets even when the outlets are densely arranged.

Description

Liquid discharge substrate, liquid discharge head, and liquid discharge device {LIQUID EJECTION SUBSTRATE, LIQUID EJECTION HEAD, AND LIQUID EJECTION APPARATUS}

The present invention relates to a liquid discharge substrate, a liquid discharge head, and a liquid discharge device used to discharge various liquids including ink.

For example, in an inkjet recording head capable of selectively ejecting ink from a plurality of ejection ports, it is necessary to densely arrange ejection ports in order to record high-quality images with high precision. Further, since the ink is thickened by evaporation of water in the ink from the discharge port, it is necessary to provide a response regarding the influence on the high-quality recording operation.

In order to address this need, Japanese Patent No. 4222826 discloses a method of circulating ink through a pressure chamber so that the thickened ink does not stay therein in a pressure chamber communicating with the discharge port. Japanese Patent No.4722826 discloses a configuration in which a member having a curved ink flow path is formed by extrusion of aluminum, and ink is forcibly flowed into a pressure chamber corresponding to each of a plurality of discharge ports through the ink flow path in the member. Are doing. Japanese Patent No. 5264000 discloses a configuration in which a member having an ink flow path that is three-dimensionally curved is formed, and ink is forcibly flowed into a pressure chamber corresponding to each of a plurality of discharge ports through the ink flow path in the member. .

However, in Japanese Patent Nos. 4222826 and Japanese Patent No. 5264000, the ink passages have a complex shape, and thus, the plurality of ink passages facilitates ink circulation through a pressure chamber corresponding to each of the plurality of discharge ports densely arranged. It cannot be placed densely.

The present invention provides a liquid discharge substrate, a liquid discharge head, and a liquid discharge device capable of circulating a liquid through a pressure chamber respectively corresponding to a plurality of discharge ports even when the discharge ports are densely arranged.

In the first aspect of the present invention, for liquid discharge comprising a discharge port for discharging a liquid, a discharge energy generating element for generating energy used to discharge the liquid, and a pressure chamber having the discharge energy generating element therein. A substrate is provided,

The liquid discharge substrate includes a first portion and a second portion shifted from each other in the thickness direction of the liquid discharge substrate,

The first portion is provided with a supply passage disposed on one side of the pressure chamber to supply liquid to the pressure chamber, and a recovery passage disposed on the other side of the pressure chamber to recover liquid from the pressure chamber,

In the second portion, a common supply flow path in communication with the plurality of supply flow paths and a common collection flow path in communication with the plurality of collection flow paths are provided.

In a second aspect of the present invention, a liquid discharge device comprising a discharge port for discharging a liquid, a discharge energy generating element for generating energy used to discharge the liquid, and a pressure chamber having the discharge energy generating element therein. A substrate is provided, and the liquid discharge substrate,

A supply flow passage disposed on one side of the pressure chamber and extending in a direction crossing a surface on which the discharge energy generating element is provided,

A recovery flow path disposed on the other side of the pressure chamber and extending in a direction crossing a surface on which the discharge energy generating element is provided,

A common supply flow path in communication with the plurality of supply flow paths,

And a common recovery flow path communicating with the plurality of recovery flow paths,

The flow path resistance per unit length from the downstream end of the supply flow path to the upstream end of the recovery flow path through the pressure chamber is represented by R, and through the pressure chamber in a state in which the liquid is not discharged from the discharge port. When the flow rate of the flowing liquid is represented by Q1 and the maximum negative pressure at which the liquid can be discharged from the discharge port is represented by P, the distance between the downstream end of the common supply channel and the upstream end of the common recovery channel (W) satisfies the relationship W<(2×P)/(Q1×R).

In a third aspect of the present invention, for liquid discharge comprising a discharge port for discharging a liquid, a discharge energy generating element generating energy used to discharge the liquid, and a pressure chamber having the discharge energy generating element therein. A substrate is provided, and the liquid discharge substrate,

A supply flow passage disposed on one side of the pressure chamber and extending in a direction crossing a surface on which the discharge energy generating element is provided,

A recovery flow path disposed on the other side of the pressure chamber and extending in a direction crossing a surface on which the discharge energy generating element is provided,

A common supply flow path in communication with the plurality of supply flow paths,

And a common recovery flow path communicating with the plurality of recovery flow paths,

The flow path resistance per unit length from the downstream end of the supply flow path to the upstream end of the recovery flow path through the pressure chamber is represented by R, and the maximum discharge amount of the liquid discharged from the discharge port is represented by Q2, and the When the maximum negative pressure at which the liquid can be discharged from the discharge port is represented by P, the distance W between the downstream end of the common supply flow path and the upstream end of the common recovery flow path is W<(2×P)/ Satisfies the relationship of (Q2×R).

In a fourth aspect of the present invention, a liquid discharge head including a liquid discharge substrate is provided, and the liquid discharge substrate includes a discharge port for discharging a liquid, and a discharge energy generating element for generating energy used for discharging the liquid. And, a pressure chamber in which the discharge energy generating element is provided,

The liquid discharge substrate includes a first portion and a second portion shifted from each other in the thickness direction of the liquid discharge substrate,

The first portion is provided with a supply passage disposed on one side of the pressure chamber to supply liquid to the pressure chamber, and a recovery passage disposed on the other side of the pressure chamber to recover liquid from the pressure chamber,

In the second portion, a common supply flow path communicating with the plurality of supply flow paths and a common recovery flow path communicating with the plurality of recovery flow paths are provided.

In a fifth aspect of the present invention, a liquid discharge device is provided, and the liquid discharge device,

Including a liquid discharge head, the liquid discharge head,

A discharge port for discharging a liquid, a discharge energy generating element for generating energy used to discharge the liquid, and a pressure chamber in which the discharge energy generating element is provided, and the liquid discharge head,

A discharge port row in which a plurality of the discharge ports are arranged,

A first flow path in communication with one of the pressure chambers,

A second flow path in communication with the other side of the pressure chamber,

A supply flow path row in which a plurality of supply flow paths for supplying the liquid to the first flow path are arranged in the arrangement direction of the plurality of discharge ports, and the plurality of supply flow paths are in a direction crossing a surface provided with the discharge energy generating element With extended supply flow path heat,

A recovery flow path row in which a plurality of recovery flow paths for recovering liquid in the second flow path are arranged in the arrangement direction of the plurality of discharge ports, wherein the plurality of recovery flow paths extend in the crosswise direction;

A common supply flow path extending in the arrangement direction of the plurality of discharge ports and communicating with the plurality of supply flow paths,

A common recovery flow path extending in the arrangement direction of the plurality of discharge ports and communicating with the plurality of recovery flow paths,

A control unit configured to control a plurality of the discharge energy generating elements,

A differential pressure generator configured to generate a differential pressure between the common supply flow path and the common recovery flow path so that liquid flows through the common supply flow path, the supply flow path, the pressure chamber, the recovery flow path, and the common recovery flow path. do.

In a sixth aspect of the present invention, a liquid discharge head is provided, wherein the liquid discharge head,

A discharge port for discharging the liquid,

A discharge energy generating element for generating energy used to discharge the liquid,

And a pressure chamber in which the discharge energy generating element is provided, and the liquid discharge head,

A discharge port row in which a plurality of the discharge ports are arranged,

A first flow path in communication with one of the pressure chambers,

A second flow path in communication with the other side of the pressure chamber,

A supply flow path row in which a plurality of supply flow paths for supplying the liquid to the first flow path are arranged in the arrangement direction of the plurality of discharge ports, wherein the plurality of supply flow paths are in a direction crossing a surface provided with the discharge energy generating element. With extended supply flow path heat,

A recovery flow path row in which a plurality of recovery flow paths for recovering liquid in the second flow path are arranged in the arrangement direction of the plurality of discharge ports, wherein the plurality of recovery flow paths extend in the crosswise direction;

A common supply flow path extending in the arrangement direction of the plurality of discharge ports and communicating with the plurality of supply flow paths,

And a common recovery flow path extending in the arrangement direction of the plurality of discharge ports and communicating with the plurality of recovery flow paths.

Further features of the present invention will become apparent from the following description of exemplary embodiments (with reference to the accompanying drawings).

Fig. 1 is an exploded perspective view showing a liquid discharge substrate according to a first embodiment of the present invention.
Fig. 2 is an exploded plan view showing the liquid discharge substrate of Fig. 1;
Fig. 3 is a plan view showing a main part of the liquid discharge substrate of Fig. 1;
4 is a cross-sectional view taken along line IV-IV of FIG. 3.
Fig. 5 is a cross-sectional perspective view showing a main part of the liquid discharge substrate of Fig. 1;
6A is a longitudinal sectional view showing a main portion of the liquid discharge substrate of FIG. 1.
6B is a side view showing a main part of the liquid discharge substrate of FIG. 1.
FIG. 7 is an explanatory view showing a main part of the liquid discharge substrate of FIG. 1.
8A and 8B are explanatory diagrams each showing a meniscus interface of ink at a discharge port.
8C is an explanatory diagram showing the relationship between the hole diameter of the discharge port and the allowable pressure limit.
9 is an explanatory diagram showing a positional relationship between a first common supply flow path and a first common recovery flow path.
10 is a flow chart showing a liquid discharge head manufacturing step.
Fig. 11 is an exploded perspective view showing a liquid discharge substrate according to a second embodiment of the present invention.
Fig. 12 is an exploded plan view showing the liquid discharge substrate of Fig. 11;
13 is an exploded perspective view showing a liquid discharge substrate according to a third embodiment of the present invention.
14 is an exploded plan view showing the liquid discharge substrate of FIG. 13.
15 is an exploded perspective view showing a liquid discharge substrate according to a fourth embodiment of the present invention.
16 is an exploded plan view showing the liquid discharge substrate of FIG. 15.
Fig. 17A is a plan view showing a main part of the liquid discharge substrate of Fig. 15;
Fig. 17B is an explanatory diagram showing an end portion of a row of discharge ports in Fig. 17A.
18A is an explanatory diagram showing the shapes of a first common supply flow path and a first common recovery flow path.
FIG. 18B is an explanatory diagram showing end portions of the first common supply flow passage and the first common recovery flow passage in FIG. 18A.
19 is an exploded perspective view showing a liquid discharge substrate according to a fifth embodiment of the present invention.
Fig. 20 is an exploded plan view showing the liquid discharge substrate of Fig. 19;
Fig. 21 is an exploded perspective view showing a liquid discharge substrate according to a sixth embodiment of the present invention.
Fig. 22 is an exploded plan view showing the liquid discharge substrate of Fig. 21;
23 is an explanatory diagram showing an arrangement relationship between the first ink flow passage and the second ink flow passage.
24A, 24B, 24C, 24D, and 24E are perspective views each showing a configuration example having various liquid discharge heads employing the liquid discharge substrate of the present invention.
25A and 25B are schematic perspective views each showing a configuration example having various inkjet recording apparatuses employing the liquid discharge head of the present invention.
Fig. 25C is an explanatory diagram showing an ink supply system for the recording head.
Fig. 26 is an explanatory diagram showing a recording apparatus according to a first application example of the present invention.
FIG. 27 is an explanatory diagram showing a first circulation form of a circulation path applied to the recording apparatus of FIG. 26;
FIG. 28 is an explanatory diagram showing a second circulation form of a circulation path applied to the recording apparatus of FIG. 26;
29 is an explanatory diagram showing the amount of ink circulation in the first and second circulation modes.
30A and 30B are perspective views showing the liquid discharge heads of FIG. 26, respectively.
31 is an exploded perspective view showing a liquid discharge head.
Fig. 32 is a diagram showing the front and rear surfaces of first, second, and third flow path members in the liquid discharge head.
33 is an enlarged perspective view showing a flow path formed by bonding the first, second and third flow path members.
34 is a cross-sectional view taken along line XXXIV-XXXIV in FIG. 33;
35A and 35B are perspective views each showing a discharge module.
36A, 36B, and 36C are explanatory diagrams each showing a recording element substrate.
37 is a perspective view showing a cross section of the recording element substrate taken along line XXXVII-XXXVII in FIG. 36A.
38 is an enlarged plan view of adjacent portions of two recording element substrates.
39A and 39B are perspective views each showing a liquid discharge head according to a second application example of the present invention.
40 is an exploded perspective view showing a liquid discharge head.
41 is an explanatory view showing a flow path member constituting a liquid discharge head.
Fig. 42 is a perspective view showing a liquid connection relationship between a recording element substrate and a flow path member in the liquid discharge head.
43 is a cross-sectional view taken along the line XXXXII-XXXXII in FIG. 42;
44A and 44B are perspective views showing a discharge module of the liquid discharge head.
45A and 45B are explanatory diagrams showing a recording element substrate.
45C is an explanatory diagram showing a cover plate.
46 is a diagram showing a second example of a recording apparatus to which the present invention is applied.
47 is an explanatory diagram showing the recording apparatus of the present invention.
48 is an explanatory diagram showing a third circulation form of the ink circulation path.
49A and 49B are explanatory diagrams showing the liquid discharge head of the present invention.
50 is an exploded perspective view showing a liquid discharge head of the present invention.
51 is a schematic explanatory diagram showing a flow path member of the present invention.
52 is an explanatory diagram showing a recording apparatus according to a third application example of the present invention.
53 is an explanatory diagram showing a fourth circulation form of the ink circulation path.
54A and 54B are explanatory diagrams each showing a liquid discharge head according to a third application example of the present invention.
55A, 55B, and 55C are explanatory diagrams each showing a liquid discharge head according to a third application example of the present invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. The liquid discharge substrate, the liquid discharge head, and the liquid discharge device in the following examples are application examples of an ink discharge substrate (a substrate for an inkjet recording head), an inkjet recording head and an inkjet recording apparatus that discharge ink as a liquid. .

Further, the liquid discharge head and liquid discharge device of the present invention are applicable to a printer, a copier, a facsimile having a communication system, a word processor having a printer, and an industrial recording apparatus combined with various processing devices. For example, the liquid discharge head and the liquid discharge device can be used for biochip manufacturing or electronic circuit printing. In addition, since the embodiments described below are specific examples of the present invention, various technical limitations thereof may be made. However, the embodiments of the present invention are not limited to the embodiments of the present specification or other specific methods, and may be modified within the spirit of the present invention.

(First Example)

1 to 10 are explanatory diagrams showing a liquid discharge unit 300 according to a first embodiment of the present invention. Here, the liquid ejection unit 300 constitutes an inkjet recording head, and the recording head is mounted on the inkjet recording apparatus as described later.

The liquid discharge unit 300 according to the present embodiment includes an orifice plate 21, a first flow path layer 22, a second flow path layer 23, and a third flow path layer 24, as shown in FIGS. 1 and 2. ), a fourth flow path layer 25, a fifth flow path layer 26, and a sixth flow path layer 27. The first flow path layer 22 is provided with a discharge energy generating element 12 that generates discharge energy for discharging ink as a liquid, and therefore, the ink in the pressure chamber 13 is transferred to the orifice plate ( It can be discharged from the discharge port 11 of 21). When the ink in the pressure chamber 13 is in a static state, the pressure in the pressure chamber 13 is maintained at a negative pressure at which the meniscus of ink is formed in the discharge port 11. When a change in pressure occurs in the pressure chamber 13, the ink ejection speed or ejection amount (volume) changes, and the ink ejection characteristics are affected. In particular, when the pressure in the pressure chamber 13 becomes lower than the predetermined pressure, ink cannot be easily discharged.

As the discharge energy generating element 12, an electrothermal conversion element (heater) or a piezoelectric element can be used. In the case of using a heater, ink in the pressure chamber 13 is changed into bubbles due to the heat generation, and the ink can be discharged from the discharge port 11 using the foaming energy.

The plurality of discharge ports 11 are densely arranged to form a row of discharge ports 16 as shown in FIG. 3. In this example, four rows of discharge ports 16 are formed. The first common supply flow path 17 of the second flow path layer 23 is, as shown in FIG. 4, through individual supply flow paths 14 and flow paths 10 corresponding to each of the pressure chambers 13, respectively. It communicates with one side of the pressure chamber 13 (left in Fig. 4). Similarly, the first common recovery flow path 18 of the second flow path layer 23 is from the pressure chamber 13 through the flow path 10 and the individual recovery flow path 15 to the other side of each pressure chamber 13 ( 4) in communication with the right. The plurality of supply passages 14 and the plurality of recovery passages 15 extend in the thickness direction of the first passage layer 22 and are arranged in the extending direction (first direction) of the discharge port rows 16, thereby It forms heat and recovery passage heat. The thickness direction of the first flow path layer 22 corresponds to a direction intersecting (orthogonal in this example) to the surface of the liquid discharge substrate on which the discharge energy generating element 12 is disposed. The first common supply channel 17 communicates with the first supply port 30 formed in the third channel layer 24 and receives ink supplied from the first supply port 30. Similarly, the first common recovery flow path 18 is in communication with the first recovery port 31 formed in the third flow path layer 24. The plurality of first supply ports 30 are arranged along the extending direction (first direction) of the discharge port rows 16 to form a first supply port row. Similarly, the plurality of first recovery ports 31 are arranged along the extending direction of the first discharge port rows 16 to form a first recovery port row. In the third flow path layer 24, four first supply port rows and four first recovery port rows are alternately arranged in parallel. The fourth flow path layer 25 is provided with a second common supply flow path 32 and a second common recovery flow path 33, and the fifth flow path layer 26 has a second supply port 34 and a second recovery port. (35) is formed. In the sixth flow path layer 27, a third common supply flow path 36 and a third common recovery flow path 37 are formed.

In the first common supply flow path 17, one of the second flow path layers 23 in the thickness direction (the side facing the first flow path layer 22) communicates with the plurality of supply flow paths 14, and the other The (side opposite to the third flow path layer 24) has a configuration in which the plurality of first supply ports 30 communicate with each other. Similarly, in the first common recovery flow path 18, one of the second flow path layers 23 in the thickness direction communicates with the plurality of recovery flow paths 15, and the other is connected with the plurality of first recovery ports 31. It has a communication configuration. In the second common supply flow path 32, one of the fourth flow path layers 25 in the thickness direction communicates with the plurality of first supply ports 30, and the other is connected with the plurality of second supply ports 34. It has a communication configuration. Similarly, in the second common recovery flow path 33, one of the fourth flow path layers 25 in the thickness direction communicates with the first recovery port 31, and the other communicates with the second recovery port 35. Have a composition. Further, the third common supply flow path 36 communicates with the plurality of second supply ports 34, and the third common recovery flow path 37 communicates with the plurality of second recovery ports 35.

The arrangement density of the plurality of second supply ports 34 and the arrangement density of the plurality of second recovery ports 35 are determined by the arrangement density of the plurality of first supply ports 30 and of the plurality of first recovery ports 31. Lower than the array density. In addition, the arrangement density of the plurality of first supply ports 30 and the arrangement density of the plurality of first recovery ports 31 are the arrangement density of the plurality of supply flow paths 14 and the arrangement density of the plurality of collection flow paths 15. Lower than The first common supply passage 17 and the first common recovery passage 18 are formed in parallel so as to follow the first direction. The second common supply flow path 32 and the second common recovery flow path 33 are formed in parallel along the second direction. The third common supply passage 36 and the third common recovery passage 37 are formed in parallel so as to follow the first direction.

As described above, the liquid discharge unit 300 of the present example is formed by stacking a plurality of flow path members. The flow path formation density of these flow paths is the sixth flow path layer 27, the fifth flow path layer 26, the fourth flow path layer 25, the third flow path layer 24, the second flow path layer 23, and It increases in the order of one flow path layer 22. Thereby, the liquid discharge unit 300 can have a configuration in which a plurality of discharge port rows 16 are provided densely while suppressing an increase in the size of each of the element substrate and the flow path member.

The first flow path layer 22 and the second flow path layer 23 are formed on the liquid discharge substrate 100 in this embodiment. In the present invention, the configuration of the third to sixth flow path layers 24 to 27 is not particularly limited. Specifically, the following 1st and 2nd structural examples are mentioned. In the first configuration example, the third flow path layer 24 is formed on the cover plate (cover member) 20 or 2020 of the embodiments of FIGS. 36C and 45C below, and a part of the fourth flow path layer 25 is 24A to 24E of the embodiment of the support member 400 is formed. Another part of the fourth flow path layer 25 is formed in the first flow path member 500 or 50 of the embodiment of FIGS. 24A to 24E or 31 below, and the fifth flow path layer 26 and the sixth flow path layer A part of (27) is formed in the second flow path member 600 or 60 of the embodiment of FIGS. 24A to 24E or 31 below. Another part of the sixth flow path layer 27 is formed on the third flow path member 370 of the embodiment of FIG. 31 to be described later. On the other hand, in the second configuration example, the third flow path layer 24 is formed on the cover plate 20 or 2020, and a part of the fourth flow path layer 25 is formed on the support member 400. Another part of the fourth flow path layer 25 and the fifth flow path layer 26 are formed on the first flow path member 500 or 50, and the sixth flow path layer 27 is formed on the second flow path member 600 or 60. Is formed. Further, the second common supply flow path 32, the second common recovery flow path 33, the second supply port 34, and the second recovery port 35 are also not limited to the configuration of this example.

The ink supplied from the outside is supplied from the third common supply channel 36 communicating with the ink inflow opening, the second supply port 34, the second common supply channel 32, the first supply port 30, and the first It is guided to the pressure chamber 13 while passing through the common supply passage 17 and the supply passage 14 in sequence. The ink in the pressure chamber 13 is a recovery flow path 15, a first common recovery flow path 18, a first recovery port 31, a second common recovery flow path 33, a second recovery port 35, and While passing through the third common recovery flow path 37 in sequence, it flows outward from the recovery port communicating with the third common recovery flow path 37. By circulating the ink in this way, the thickened ink that tends to stay in the pressure chamber 13 flows to the outside. Accordingly, it is possible to suppress a decrease in the ink ejection speed from the ejection port 11 and a change in the colorant density of the ink. Hereinafter, this forced flow of ink is referred to as "ink circulation flow".

In this example, the supply flow passage 14 and the recovery flow passage 15 are disposed to face each other with the discharge port 11 interposed therebetween, as shown in Figs. 3, 4, and 5. In this way, since the supply flow passage 14 and the recovery flow passage 15 face each other, a high-efficiency ink circulation flow is generated in the pressure chamber 13 and the discharge port 11. Therefore, it is possible to more efficiently suppress a change in the colorant density of the ink and a decrease in the ink ejection speed. Further, the supply flow passage 14 and the recovery flow passage 15 are individually formed at a plurality of positions in the first direction corresponding to the extending direction of the discharge port rows 16 so as to correspond to each of the pressure chamber 13. In this way, since the supply passage 14 and the recovery passage 15 are formed individually at a plurality of positions, the discharge energy generation element 12 is provided between the adjacent supply passages 14 and the adjacent recovery passages 15. ), you can place a wire to drive it. Therefore, it is not necessary to arrange a wiring extending in the first direction between the supply passage 14 and the discharge port 11 and between the recovery passage 15 and the discharge port 11. Thus, the size of the portion between them can be further reduced. The number relationship between the supply flow path 14 and the discharge port 11 may be 1 to 1, 1 to 2, or 1 to 5, and the number of pressure chambers 13 communicating with the supply flow path 14 is this example. Is not limited to 1.

In this example, since the ink circulation flow is generated in the pressure chamber 13 and the discharge port 11, a flow path is formed as follows.

As shown in FIG. 2, the first common supply flow path 17 extends in a first direction to communicate with the plurality of supply flow paths 14, and the pressure chamber 13 and the pressure chamber 13 through each supply flow path 14 Communicate. Similarly, the first common recovery flow path 18 extends in the first direction and communicates with the plurality of recovery flow paths 15, and communicates with the pressure chamber 13 through the respective recovery flow paths 15.

In this way, in the first flow path layer 22 and the second flow path layer 23, the supply flow path 14, the recovery flow path 15, the first common supply flow path 17, corresponding to the discharge port row 16, And a series of ink flow paths including a first common recovery flow path 18. Through this ink flow path, an ink circulation flow can be generated in the pressure chamber 13 of the liquid discharge substrate 100 and the discharge port 11 of the orifice plate 21.

In addition, as shown in Fig. 6A, sidewalls forming the supply flow path 14, the recovery flow path 15, the first common supply flow path 17, and the first common recovery flow path 18 are formed by the first flow path layer ( 22) is substantially orthogonal to the front and back surfaces (upper and lower surfaces of the drawing). Here, the substantially orthogonal state includes a tapered slope formed when the first flow path layer 22 and the second flow path layer 23 are processed. The supply passage 14, the recovery passage 15, the first common supply passage 17 and the first common recovery passage 18 may be formed by, for example, dry etching. In addition, these passages may be formed by laser processing or a combination of dry etching and laser processing. The depth directions of the supply flow path 14, the recovery flow path 15, the first common supply flow path 17, and the first common recovery flow path 18 (up-down direction in FIG. 6A) are of the first flow path layer 22. It is substantially perpendicular to the surface. Accordingly, when the ink flow path is densely formed with high efficiency, the ink circulation flow can be generated very efficiently in the pressure chamber 13 and the discharge port 11 densely formed in the first flow path layer 22.

(Relation between the first common supply passage 17 and the first common recovery passage 18 (1))

The first common supply flow path 17 and the first common recovery flow path 18 are formed as follows.

6A and 6B, the distance (beam width) between the downstream end of the first common supply passage 17 and the upstream end of the second common recovery passage 18 is represented by W1, and the supply passage The distance between (14) and the recovery flow path 15 is represented by W2. Further, the flow path resistance per unit length from the downstream end of the supply flow path 14 to the upstream end of the recovery flow path 15 through the flow path 10, the pressure chamber 13 and the flow path 10 is represented by R, The flow rate of the ink circulation flow generated in each pressure chamber 13 is indicated by Q1. The flow path resistance R is expressed by an equation including a term indicating the viscosity of the ink (including a time factor). In addition, the maximum negative pressure in the pressure chamber 13 within the range in which the meniscus interface of the ink does not collapse at the discharge port 11, or the maximum negative pressure in the pressure chamber 13 within the range in which ink can be properly discharged from the discharge port 11 Is represented by Pmax. These elements have the relationship of equation (1). The relational expression (1) will be described later.

W2<(2×Pmax)/(Q1×R)… Equation (1)

As shown in FIG. 8A, when the meniscus interface subsides due to the influence of the negative pressure, and the meniscus interface collapses according to the increase of the negative pressure, as shown in FIG. 8B, the discharge energy generating element 12 There is no ink on it, and the ink cannot be easily ejected under normal conditions. When the surface tension of the ink is 30 mN/m and 20 mN/m, the diameter of the discharge port 11 and the allowable pressure limit at the discharge port 11 have a relationship as shown in Fig. 8C. In general, the meniscus of ink at the discharge port depends on the aperture of the discharge port and the surface tension of the ink. However, if the pressure of -1000 mmAq or more is not maintained, the meniscus interface collapses. Therefore, the maximum negative pressure within the range in which the meniscus interface does not collapse is -1000 mmAq, for example, when the diameter of the discharge port is 12 um and the surface tension of the ink is 30 mN/m. Further, even in the range in which the meniscus interface does not collapse, the amount of ink to be discharged decreases due to the settling of the meniscus interface as shown in Fig. 8A. Therefore, a lot of ink sub-droplets (satellites) are generated by affecting the discharge state of ink.

Here, the appropriate ink ejection state refers to a state in which ink is ejected satisfactorily to the extent that confusion in the recorded image is not visually recognized. In particular, it is preferable to adopt an ink ejection state that is not visually confirmed due to a small change in the ink ejection amount. In addition, when main droplets and amulets (satellite) of ink are generated during the ink ejection operation, the main droplets of ink formed by the main droplets landing on the recording medium are applied to the ink formed by the satellite. The ink discharge state in which at least a part of the minor dot comes into contact is preferable.

As described above, the maximum negative pressure Pmax represents a negative pressure at which the meniscus interface collapses or ink cannot be properly discharged when the pressure is greater than the maximum negative pressure. In addition, when a satellite is generated, it is preferable that the satellite hits the recording medium so that the minor dot is located in the main strip. For example, the maximum negative pressure (Pmax) was 500 mmAq. In addition, the ink circulation flow amount Q1 is a flow rate capable of suppressing a decrease in the ink discharge speed and a change in the colorant density of the ink. That is, the flow rate can suppress the possibility that the ink ejection speed decreases due to evaporation of water in the ink from the ejection port 11, and the ink landing position changes to a recognizable degree. Further, the flow rate can suppress the possibility that the colorant density of the ink changes due to the evaporation of water in the ink from the discharge port 11, and the recorded image becomes uneven to an observable degree. For example, the ink circulation flow quantity Q1 represents the circulation flow quantity which can suppress the decrease in the ink ejection speed to within 10% of the normal ejection state. In the experimental example, the ink circulation flow rate was calculated as a flow rate of 0.05 m/s or more in the pressure chamber 13. In addition, in other experimental examples, the flow rate was 0.1 m/s.

When the relationship of equation (1) is satisfied, the pressure in the first common supply flow path 17 can be maintained at a negative pressure. In the inkjet recording head, it is preferable that the pressure in the flow path of the recording head is maintained at a negative pressure. When the pressure is a positive pressure, the following possibilities arise. That is, when the pressure in the ink passage of the recording head is a positive pressure, ink is liable to leak from the constituent elements of the recording head. In addition, ink tends to leak from the discharge port 11. For example, even when the pressure in the first common supply passage 17 is a positive pressure and the pressure in the pressure chamber 13 is maintained at a negative pressure due to a pressure loss due to the ink circulation in the ink circulation state, the change in the ink circulation flow Accordingly, there is a fear that the pressure loss may change and the pressure in the pressure chamber 13 may become a positive pressure. As an extreme example, when the ink circulation flow is stopped, the pressure in the pressure chamber 13 becomes the same positive pressure as in the first common supply flow path. In order to prevent the pressure in the pressure chamber 13 from becoming a positive pressure, complicated control of the ink supply system is required.

(Explanation of relational expression (1))

Next, Equation (1) for maintaining the pressure in the first common supply passage 17 at a negative pressure will be described in detail.

The differential pressure ΔP between the supply flow passage 14 and the recovery flow passage 15 is expressed by equation (2).

ΔP=Q1×R×W2 ... Equation (2)

In addition, when the pressure of the supply flow path 14 is represented by Pin and the pressure of the recovery flow path 15 is represented by Pout, the formula (3) holds. In addition, when the discharge port 11 is located in the middle between the supply passage 14 and the recovery passage 15, the pressure Pn of the discharge port 11 is expressed by equation (4).

ΔP=Pin-Pout ... Equation (3)

Pn=(Pin+Pout)/2 ... Equation (4)

From equations (3) and (4), equation (5) holds.

Pin=Pn+(ΔP/2) ... Equation (5)

In order to maintain the pressure of the first common supply flow passage 17 at a negative pressure, it is necessary to satisfy Expression (6).

Pin=Pn+(ΔP/2)<0 ... (6)

Equation (6) can be transformed into Equation (7).

-Pn>ΔP/2 ... Equation (7)

Since the equation of Pn>-PMAX needs to be satisfied in order to discharge ink normally, equation (8) holds.

Pmax>ΔP/2 ... Equation (8)

From the above equations (2) and (8), the above equation (1) can be derived.

In addition, W1 and W2 are in the relationship of equation (9).

W1<W2 ... Equation (9)

From the relationship of equation (9), the following equation (10) holds.

W1<(2×Pmax)/(Q1×R) ... Equation (10)

When setting the interval W1 so as to satisfy the relationship of equation (10), the pressure of the first common supply passage 17 can be maintained at a negative pressure, and thus the reliability of the substrate and the recording head can be improved.

In particular, in the recording head having high flow path resistance in the pressure chamber 13, it is necessary to make the gap (beam width) W1 smaller. In a recording head using a piezoelectric element as the discharge energy generating element 12, since the flow path resistance of the pressure chamber 13 is usually reduced, the interval W1 can be increased. On the other hand, in a recording head using a heater as the discharge energy generating element 12, since the flow path resistance of the pressure chamber 13 is usually increased, the interval W1 needs to be made smaller.

(Relationship between the first common supply flow path 17 and the first common recovery flow path 18 (2))

When the maximum discharge amount of the ink discharged from the discharge port 11 is expressed by Q2, it is preferable to set the first common supply flow path 17 and the first common recovery flow path 18 so as to satisfy the relationship of equation (11). .

W1<(2×Pmax)/(Q2×R) ... Equation (11)

When the ink circulation flow amount Q1 is set larger than the maximum discharge amount Q2, the reverse flow of the ink circulation flow can be suppressed even when the ink is discharged to the maximum. When the reverse flow of the ink circulation flow occurs, heat generated by the discharge of ink is not discharged by the ink circulation flow. In addition, ink may be excessively heated by the reverse flow of exhaust heat, and ink ejection failure may occur due to reverse flow of deposits in the ink passage. However, since the reverse flow of the ink circulation flow is suppressed, such a state can be suppressed.

When setting the first common supply flow path 17 and the first common recovery flow path 18 to satisfy the relationship of equation (11), the pressure in the first common supply flow path 17 is reduced while suppressing the reverse flow of the ink circulation flow. Can be maintained under negative pressure. As a result, the reliability of the substrate and the recording head can be improved.

As a result of the experiment, when the height of the pressure chamber 13 is set to 20 μm, the viscosity of the ink is set to 10 cP, and the beam width (W1) is set to 200 μm or less, the ink circulation flow rate suppresses the reverse flow of the ink circulation flow. For this purpose, even at 0.1 m/s, the pressure in the first common supply passage 17 can be maintained at a negative pressure. In addition, when the beam width W is set to 100 μm or less, even when ink of 10 pl is discharged at a discharge frequency of 30 kHz (drive frequency of the recording head), the first common supply flow path is suppressed while the reverse flow of the ink circulation flow is suppressed. (17) The internal pressure can be maintained as a negative pressure.

(The arrangement relationship between the flow paths (17, 14) and the arrangement relationship between the flow paths (18, 15))

In addition, the arrangement relationship between the first common supply flow path 17 and the supply flow path 14 and the arrangement relationship between the first common recovery flow path 18 and the recovery flow path 15 may be set as follows. That is, as shown in FIG. 6B, the center L1 of the supply flow path 14 in the second direction is more than the center L2 of the first common supply flow path 17 in the second direction. It is set in a position close to. Similarly, the center L3 of the recovery flow path 15 in the second direction is set to a position closer to the discharge port 11 than the center L4 of the first common recovery flow path 18 in the second direction. In this way, if the supply flow passage 14 and the recovery flow passage 15 are provided close to the discharge port 11, the width W2 is set small even when the same beam width W1 is set, and the pressure in the discharge port 11 is reduced to an appropriate pressure. It can be easier to maintain.

(Arrangement relationship between the flow path 17 and the flow path 18)

It is preferable to set the arrangement relationship between the 1st common supply flow path 17 and the 1st common recovery flow path 18 as follows.

That is, as shown in FIG. 9, when the beam width between the first common high-grade flow path 17 and the first common recovery flow path 18 positioned between adjacent outlet rows 16 is represented by W3, the beam width W3 Is set larger than the beam width W1. When the beam width W3 is set to be large, the strength of the substrate can be improved. Fig. 9 is a diagram showing the liquid discharge substrate viewed from the rear side in a state where the discharge port 11 is clearly visible. In this way, the first common supply passage 17 and the first common recovery passage 18 communicating with the same outlet row 16 are formed so as to be set to be small in the beam width W1. On the other hand, the first common supply flow path 17 communicating with one of the adjacent discharge port rows 16 is separated from the first common recovery flow path 18 so that the beam width W2 is increased. Thereby, the backflow of the ink circulation flow can be suppressed, and the strength of the substrate can be improved while maintaining the pressure in the first common supply flow passage 17 at a negative pressure.

(Structure to suppress changes in ink circulation flow and pressure (1))

In addition, in this embodiment, the following structure is provided in order to suppress changes in the ink circulation flow rate and pressure in each pressure chamber 13.

That is, as shown in FIGS. 1 and 2, the plurality of first supply ports 30 communicate with the first common supply flow path 17. Similarly, the plurality of first recovery ports 31 communicate with one first common recovery flow path 18. The first supply port 30 and the first recovery port 31 are arranged so that the change in the ink circulation flow rate and the pressure change in each pressure chamber 13 are within a range that does not affect the ink discharge characteristics. Specifically, the first supply ports 30 and the first recovery ports 31 are alternately arranged in the first direction in which the discharge port rows 16 extend. Accordingly, the distance between the first supply port 30 and the first recovery port 31 in the first direction can be further narrowed. Therefore, even when the width of each of the first common supply passage 17 and the first common recovery passage 18 is relatively narrow, it is possible to suppress a change in ink circulation flow rate and pressure change in each pressure chamber 13. .

(Structure to suppress changes in ink circulation flow and pressure (2))

In addition, in this embodiment, the following structure is provided in order to suppress the change in the ink circulation flow rate and the change in pressure in each pressure chamber 13.

That is, as shown in FIGS. 1 and 2, the second common supply passage 32 extends in the second direction and communicates with a plurality of first supply ports 30 arranged in the second direction. Similarly, the second common recovery passage 33 extends in the second direction and communicates with the plurality of first recovery ports 31 arranged in the second direction. Further, the plurality of second common supply flow paths 32 are integrally communicated with one third common supply flow path 36 via the second supply port 34. Similarly, the plurality of second common recovery flow paths 33 are integrally communicated with one third common recovery flow path 37 via the second recovery port 35.

As described above, when the ink flow paths communicate with each other by the six-layer structure, the plurality of first common supply flow paths 17 formed with narrow pitches to fit the plurality of discharge port rows 16 densely arranged are provided with a plurality of first supply flow paths. It is finally integrated into one third common supply flow path 36 through the sphere 30. Similarly, the plurality of first common recovery flow paths 18 formed with narrow pitches to fit the plurality of discharge port rows 16 arranged in a dense manner, through the plurality of first recovery ports, finally one third common recovery flow path ( 37). Accordingly, the plurality of discharge port rows 16 can be densely arranged without expanding the width of each of the first common supply flow passage 17 and the first common recovery flow passage 18. Further, in each of the pressure chambers 13 corresponding to the respective discharge ports 11 of the plurality of discharge port rows 16 arranged in such a dense manner, it is possible to suppress changes in the ink circulation flow rate and pressure. In addition, with respect to the densely arranged discharge ports 11, ink can be supplied from an ink tank (not shown) while suppressing changes in the ink circulation flow rate and pressure in the pressure chamber 13, and the ink can be recovered to the ink tank. can do. Thereby, not only the recording head and the recording apparatus having the same, but also various liquid ejecting heads and the liquid ejecting apparatus having the same can be provided in a small size.

(Structure to suppress changes in ink circulation flow and pressure (3))

Further, in order to suppress the change in the ink circulation flow rate and the pressure change in each pressure chamber 13, the following structure is preferable.

That is, the first supply ports 30 and/or the first recovery ports 31 located at both ends of the discharge port row 16 are the first supply ports 30 and/or the first supply ports 30 located at positions other than both ends thereof. Alternatively, it is formed smaller than the first recovery port 31. That is, the opening of the former first supply port 30 and/or the first recovery port 31 is formed smaller than the opening of the latter first supply port 30 and/or the first recovery port 31 . In the vicinity of the first supply ports 30 located at both ends of the discharge port row 16, only one of the first supply ports 30 located at both ends of the discharge port row 16 in the first direction is the discharge port row 16 ) Of the discharge port 11 is located. Accordingly, the ink flow rate of the first supply ports 30 located at both ends of the discharge port row 16 is less than that of the other first supply ports 30. Similarly, in the vicinity of the first recovery ports 31 located at both ends of the discharge port row 16, only one side of the first recovery ports 31 located at both ends of the discharge port row 16 in the first direction. The discharge port 11 of (16) is located. Accordingly, the ink flow rate of the first recovery ports 31 located at both ends of the discharge port row 16 is less than that of the other first recovery ports 31.

In this way, the first supply port 30 and/or the first recovery port 31 formed at both ends of the discharge port row 16 are formed to have a small size, thereby increasing the flow resistance. Accordingly, the pressure loss occurring in the first supply port 30 and/or the first recovery port 31 formed at both ends of the discharge port row 16 is different from the first supply port 30 and/or the first recovery port. It can be adjusted similarly to the pressure loss occurring in (31). Therefore, the first supply port 30 different from the flow rate of the ink flowing into the pressure chamber 13 through the first supply port 30 and/or the first recovery port 31 at both ends of the discharge port row 16 And/or it is possible to reduce the difference between the ink flow rate of the ink flowing into the pressure chamber 13 through the other first recovery port 31. As a result, it is possible to further suppress the difference in the amount of ink circulation in each of the pressure chambers 13.

(Structure to suppress changes in ink circulation flow and pressure (4))

Further, in order to suppress the change in the ink circulation flow rate and the pressure change in each pressure chamber 13, the following structure is preferable.

That is, as shown in Fig. 7A, the area "a" between the end of the discharge port row 16 and the liquid discharge substrate 100 is set large. For example, the area "a" may be used as an arrangement space for a connection pad 150 that transmits and receives an electric signal to and from the liquid discharge substrate 100 and a driving circuit of the discharge energy generating element 12. In addition, as in the perspective view of portions (b) and (c) of Fig. 7 showing the liquid discharge substrate 100 viewed from the discharge port 11 side using the region "a", the first recovery port 31 It is desirable to place ). That is, in the first direction in which the discharge port row 16 extends, the first recovery port 31 is disposed to overlap the discharge port 11 located at the end of the discharge port row 16. In part (b) of FIG. 7, the left end of the first common recovery flow path 18 and the left end of the first recovery port 31 are located at the same position. In addition, in the part (c) of FIG. 7, the left end of the first common recovery flow path 18 and the left end of the first recovery port 31 swell to the left side more than the recovery flow path 15 located at the left end. Are doing.

In (a) and (b) of FIG. 7, ink passing through the pressure chamber 13 located at the end of the discharge port row 16 is first from the first supply port 30, as indicated by arrow A1. It flows into the first common supply flow path 17 and the supply flow path 14. After that, the ink passes through the pressure chamber 13, the recovery flow path 15 and the first common recovery flow path 18 located at the end of the discharge port row 16, as indicated by arrow A2, and then the first It flows out from the recovery port 31. Part (d) of FIG. 7 is a comparative example in the case where the first recovery port 31 is disposed so as not to overlap with the discharge ports 11 located at the end portions of the discharge port rows 16 in the first direction. In (d) of FIG. 7, the ink passing through the pressure chamber 13 located at the end of the discharge port row 16 is, first, as indicated by arrow A1, the first common supply flow path from the first supply port 30 It flows out from (17) and the supply flow path (14). After that, the ink passes through the pressure chamber 13 and the recovery flow path 15 located at the end of the discharge port row 16, as indicated by arrow A2, and as indicated by arrow A3, the first common recovery flow path ( After passing through 18), it flows out from the first recovery port 31.

In parts (b) and (c) of FIG. 7, compared to the configuration of (d) of FIG. 7, it flows from the first supply port 30 located at the end of the first direction and passes through the pressure chamber 13. The length of the ink flow path of ink flowing out from the first recovery port 31 can be shortened. In other words, since the maximum pressure loss in the first common supply flow path 17 and the first common recovery flow path 18 located near the end portions of the discharge port rows 16 is reduced, each pressure chamber 13 It is possible to suppress a change in the ink circulation flow amount. In addition, when the first supply port 30 is located at the end in the first direction instead of the first recovery port 31, the first supply port 30 is located at the end of the discharge port row 16 in the first direction. It may be disposed so as to overlap with the discharge port (11).

(Temperature distribution suppression structure)

In this embodiment, in order to suppress the temperature distribution in the recording head, the following structure is provided.

That is, as shown in FIGS. 1 and 2, the first recovery ports 31 are disposed at both ends of the discharge port row 16. In the case of forcibly circulating ink through each pressure chamber 13 as in this example, heat generated from the discharge energy generating element 12 or the like is recovered by the ink. For this reason, the temperature of the ink in the ink recovery side passage is higher than the temperature of each pressure chamber 13.

In addition, even if sufficient ink circulation flow is secured to suppress the effect of evaporation of water in the ink from the discharge port 11, there is a case that the amount of ink discharged simultaneously from the plurality of discharge ports 11 becomes larger than the ink circulation flow rate. have. In this case, ink is also supplied into the pressure chamber 13 from the second common recovery flow path 37. That is, from the second common recovery flow path 37, the second recovery port 35, the second common recovery flow path 33, the first recovery port 31, the first common recovery flow path 18, and the recovery flow path 15 ), ink is supplied into the pressure chamber 13. For this reason, when ink is simultaneously discharged from the plurality of discharge ports 11, the high temperature ink in the first recovery port 31 may be supplied into the pressure chamber 13. In this case, since the temperature of the ink in the vicinity of the first recovery port 31 is higher than the temperature of the ink in the vicinity of the first supply port 30, the discharge port 11 and the first recovery port in the vicinity of the first supply port 30 (31) There is a concern that a difference in ink discharge speed may occur between the discharge ports 11 in the vicinity. In addition, when the first supply port 30 is located at one end side of both ends of the discharge port row 16 and the first recovery port 31 is located at the other end side, the entire discharge port row 16 A slope of the temperature distribution occurs in the arrangement direction of the discharge ports 11, and the width of the temperature distribution over the entire recording head increases. As a result, there is a fear that a change in ink discharge characteristics may occur at each discharge port 11.

In the present embodiment, since the first recovery ports 31 are disposed at both ends of the discharge port row 16, the inclination of this temperature distribution can be suppressed, and thus the change in ink discharge characteristics can be suppressed. In addition, the same effect can be obtained when the first supply ports 30 are disposed at each of both ends of the discharge port row 16. However, as in the present embodiment, it is preferable to arrange the first recovery ports 31 at each of both ends of the discharge port row 16.

That is, in the liquid discharge substrate 100, as described above, the region "a" in which the discharge port 11 is not disposed between each of both ends of the discharge port row 16 and the end of the liquid discharge substrate 100 Is set to be large, and thus heat generated by the ink ejection operation is radiated from the region "a". Therefore, when the recovery discharge ports 11 discharge ink, the temperature values at both ends of the discharge port row 16 tend to be lower than the temperature values of other portions. Since the first recovery ports 31 are disposed at each of both ends of the discharge port row 16, high-temperature ink can be supplied to both ends of the discharge port row 16 in this case. Therefore, since the temperature values at both ends of the discharge port row 16 are set high, the temperature difference with other portions can be reduced. As a result, since the width of the temperature distribution over the entire recording head is reduced, it is possible to suppress a change in ink ejection characteristics.

10 is a flowchart showing an example of the steps of manufacturing the liquid discharge head of this embodiment.

First, a nozzle is formed on the liquid discharge substrate 100 on which the discharge energy generating element 12 and necessary circuits are formed by the nozzle forming step S1. The nozzle is a part that discharges ink using the discharge energy generating element 12 and includes a discharge port 11 and a pressure chamber 13. Thereafter, a first common supply flow path 17 and a first common recovery flow path 18 are formed on the rear surface of the liquid discharge substrate 100 by the rear supply path forming step S2. Next, a cover plate 20 (cover member) or 2020 of the embodiment shown in Fig. 36C or 45C is formed on the back surface of the liquid discharge substrate 100 by the cover member forming step S3. Thereafter, in the cutting step (S4), the shape of the liquid discharge substrate 100 is processed from a wafer shape to a chip shape. Thereafter, the liquid discharge substrate 100 is bonded to the support member 400 and the first flow path member 500 of the embodiments of FIGS. 24A to 24E by the bonding step S5.

In this way, the cover plate serving as the third flow path layer is formed on the back surface of the liquid discharge substrate 100 by the lid member forming step S3 before the bonding step S5, so that the wafer type liquid discharge substrate A first supply port 30 and a first recovery port 31 may be formed in (100). Since the cover plate is processed when the liquid discharging substrate 100 has a wafer shape, processing precision is higher than that of machining or molding, and thus fine holes can be formed with higher precision. In addition, the cover plate may be formed thin. Therefore, the discharge port 11 can be arranged with higher precision. In addition, since the flow path resistance of the first supply port 30 and the first recovery port 31 is reduced in a state where the change in flow resistance is small, the differential pressure for generating the ink circulation flow can be stabilized, and thus the circulation flow Change can be suppressed little.

The cover plate may be formed by a silicon substrate. That is, since the cover plate made of the wafer-type silicon substrate is bonded to the wafer-type liquid-discharging substrate 100, the number of steps compared to the case of bonding the cover plate to the chip-type liquid-discharging substrate 100 Can be reduced. Further, the cover plate may be formed by a resin film. As in the case of the silicon substrate, since the cover plate can be bonded by laminating a film-type resin on the wafer-type liquid-discharging substrate 100, the cover plate is attached to the chip-type liquid-discharging substrate 100. Compared to the case of bonding, the number of steps can be reduced.

The order and contents of the steps in FIG. 10 are only examples and do not limit the present invention. For example, the sequence of the nozzle forming step (S1), the back supply path forming step (S2), the cover member forming step (S3), and the cutting step (S4) is the cover member forming step (S3) before the bonding step (S5). As far as can be implemented, it is not limited to the example of FIG. 10.

(Second example)

11 and 12 are explanatory diagrams showing a liquid discharging unit 300 according to the second embodiment of the present invention, and portions similar to those of the above-described embodiment are denoted by the same reference numerals, and the description is omitted. 11 is an exploded perspective view showing the liquid discharge unit 300, and FIG. 12 is an exploded plan view showing the liquid discharge unit 300.

In this embodiment, the first common supply flow path 17 and the second common supply flow path 32 communicate at one end side of the discharge port row 16, and the first common recovery flow path 18 at the other end side thereof. And the second common recovery passage 33 communicate with each other. In this embodiment, since the third flow path layer 24 of the first embodiment is not provided, and the first supply port 30 and the first recovery port 31 of the first embodiment can be omitted, the flow path structure is Can be simplified.

(Third Example)

13 and 14 are explanatory diagrams showing a liquid discharging unit 300 according to the third embodiment of the present invention, and portions similar to those of the above-described embodiment are denoted by the same reference numerals, and the description is omitted. 13 is an exploded perspective view showing the liquid discharge unit 300, and FIG. 14 is an exploded plan view showing the liquid discharge unit 300. As shown in FIG.

In this embodiment, on the one end side of the discharge port row 16, the first common supply flow path 17 and the first supply port 30 communicate with each other, and the first common recovery flow path 18 and the first recovery port ( 31) are in communication with each other. Similarly, also on the other end side of the discharge port row 16, the first common supply flow path 17 and the first supply port 30 communicate with each other, and the first common recovery flow path 18 and the first recovery port 31 They are in communication with each other. When the first supply port 30 and the first recovery port 31 are disposed at both ends of the discharge port row 16, compared to the second embodiment, ink circulation in the first direction in which the discharge port row 16 extends A change in the amount of flow and a change in pressure in each pressure chamber 13 can be suppressed. In addition, each of the second common supply flow path 32 and the second common recovery flow path 33 may be disposed at two positions.

Thus, in this embodiment, since the number of the first supply port 30 and the second recovery port 31 is reduced, the structure of the ink flow path can be simplified.

(Example 4)

15 to 18B are explanatory diagrams showing the liquid discharge unit 300 according to the fourth embodiment of the present invention, and portions similar to those of the above-described embodiment are denoted by the same reference numerals, and the description is omitted. 15 is an exploded perspective view of the liquid discharge unit 300, and FIG. 16 is an exploded plan view of the liquid discharge unit 300. The planar shape of the liquid discharge unit 300 in this embodiment is a parallelogram (a parallelogram in which the adjacent side is not a right angle), but for ease of explanation, the planar shape is shown as a rectangle. 17A is a plan view showing the liquid discharge substrate 100 according to the present embodiment, and FIG. 17B is a perspective view showing the structure of the end portions of the discharge port rows 16.

As shown in Fig. 17A, the planar shape of the liquid discharge substrate 100 of this embodiment is formed in a parallelogram, compared to the liquid discharge substrate 100 of Fig. 7(a) of the first embodiment. The area "a" between the end of the outlet row 16 and the end of the element substrate is small. In this embodiment, the connection pad 150 for transmitting and receiving an electric signal between the liquid discharge substrate 100 and the outside, and the driving circuit such as the discharge energy generating element 12, as shown in Fig. 17A Likewise, it is disposed on the long side of the liquid discharge substrate 100. When such a liquid discharge substrate 100 is combined to obtain an elongated recording head (line head), the liquid discharge substrate 100 is disposed in a substantially one row shape as shown in Fig. 17A instead of a zigzag shape. can do. By this arrangement, the ends of the discharge port rows 16 of the adjacent liquid discharge substrate 100 can be easily overlapped with each other in the second direction as shown in FIG. 17A. Here, "substantially arranged in a row shape" refers to a state in which the liquid discharge substrates 100 adjacent in both the first direction and the second direction partially overlap each other.

As described above, in this embodiment, the discharge port 11 is arranged even near the end portion of the liquid discharge substrate 100. In this embodiment, as shown in (b) and (c) of FIG. 7 of the first embodiment, the first supply port 30 at a position where the ends of the discharge port rows 16 of the liquid discharge substrate 100 overlap. ) Or it is difficult to arrange the first recovery port 31. Accordingly, in this embodiment, as shown in FIG. 17B, the first supply port 30 or the first recovery port 31 is disposed at a position displaced toward the center with respect to the end of the discharge port row 16.

In this embodiment, as shown in Figs. 15 and 16, in order to suppress a change in the ink circulation flow rate and pressure in each pressure chamber 13 and to suppress the temperature distribution in the liquid discharge substrate 100, the discharge port A first supply port 30 is disposed in the vicinity of each of both ends of the row 16.

As in the present embodiment, when the first supply port 30 is disposed near the end of the discharge port row 16, the first common supply passage 17 and the first common located at the end of the discharge port row 16 The differential pressure between the recovery flow paths 18 is greater during the ink ejection operation compared to the ink circulation operation using the initial differential pressure. On the other hand, as in the first embodiment, when the first recovery port 31 is disposed at the end of the discharge port row 16, the first common supply passage 17 and the first common supply passage 17 at the end of the discharge port row 16 1 The differential pressure between the common recovery passages 18 is smaller during the ink ejection operation compared to the ink circulation operation using the initial differential pressure. When the pressure difference between the first common supply flow passage 17 and the first common recovery flow passage 18 decreases, the ink circulation flow rate decreases. Therefore, the effect of suppressing the effect of water evaporation in the ink from the discharge port 11 is reduced. In other words, the effect of suppressing a decrease in the ejection speed of the ink and a change in the color material density of the ink is reduced. Therefore, the differential pressure is preferably set large. As in the present embodiment, since the first supply ports 30 are disposed near both ends of the discharge port row 16, the influence of the change in the ink circulation flow rate can be reduced.

The pressure in the first supply port 30 is set higher than the pressure in the first recovery port 31 in order to generate an ink circulation flow, and when the ink is discharged, the pressure chamber 13 is passed through the first supply port 30. ), it becomes easier to supply ink. In this way, since the first supply ports 30 that facilitate ink supply are disposed near the end portions of the discharge port rows 16, when simultaneously discharging ink from the plurality of discharge ports 11, the first common supply passage 17 ) And the pressure loss occurring between the first common recovery flow path 18 may be reduced.

Further, in this embodiment, as described above, since the region "a" between the end of the discharge port row 16 and the end of the element substrate is small, the heat generated by the ejection operation of ink is radiated from the region "a". The degree to which it becomes is small. Since the region "a" is small, the portion of the first common supply passage 17 from the first supply port 30 to the end of the discharge port row 16 becomes longer, as shown in Fig. 17B. Similarly, the portion of the first common recovery flow path 18 from the first recovery port 31 to the end of the discharge port row 16 is lengthened. Accordingly, ink passing through the portions of the first common supply passage 17 and the first common recovery passage 18 easily receives heat from the liquid discharge substrate 100. Therefore, when ink is simultaneously discharged from the plurality of discharge ports 11, the temperature at the end of the discharge port row 16 tends to be higher than that of other parts. Further, the pressure loss occurring in each ink flow path during the ink ejection operation increases, and the pressure becomes non-uniform at the end of the ejection port row 16.

However, in this embodiment, as described above, since the first supply ports 30 are disposed at each of both ends of the discharge port row 16, with respect to the discharge ports 11 near the ends of the discharge port rows 16, A large amount of ink is supplied from the first supply port 30 disposed in the vicinity thereof. As a result, when the ink is simultaneously discharged from the plurality of discharge ports 11, the amount of the high-temperature ink supplied from the first supply port 30 is reduced, thus reducing the temperature increase at the end of the discharge port row 16. I can.

Specifically, ink supplied from the first supply port 30 first flows from the first common supply channel 17 to the supply channel 14 as indicated by arrow B1 in FIG. 17B. After that, the ink passes through the pressure chamber 13 and the recovery flow path 15 located at the end of the discharge port row 16 as indicated by arrow B2, and then the first common recovery as indicated by arrow B3. It flows out from the first recovery port 31 through the flow path 18.

Thus, in this embodiment, since the first supply ports 30 are disposed at each end of the discharge port row 16, changes in ink circulation flow and pressure can be suppressed, and the temperature distribution in the recording head is suppressed to be small. can do. Accordingly, a decrease in ink ejection speed due to evaporation of water in the ink from the ejection port 11, a change in ink colorant concentration, and a change in ink ejection characteristics can be suppressed, and high-quality images can be recorded with higher precision. In addition, it is preferable that the first common supply flow path 17 and the first common recovery flow path 18 have the shapes shown in Fig. 18B. FIG. 18A is a view of the liquid discharge substrate 100 viewed from the rear side thereof, and FIG. 18B is an enlarged view showing end portions in the longitudinal direction of the first common supply passage 17 and the first common recovery passage 18 in FIG. 18A Is also Both ends of the first common supply flow path 17 and the first common recovery flow path 18 in communication with the same discharge port row 16 in the longitudinal direction are provided at the same positions shown in FIG. 18B. In addition, as shown in FIG. 18A, in the two outlet rows 16 provided in parallel so as to be adjacent to each other, a first common supply passage 17 and a first common recovery passage of one of the adjacent outlet rows 16 The first common supply flow path 17 and the first common recovery flow path 18 on the other side of (18) and adjacent discharge port rows 16 have the following positional relationship. That is, both ends in the longitudinal direction of the first common supply passage 17 and the first common recovery passage 18 in communication with one of the adjacent outlet rows 16, and the first common supply passage in communication with the other. Both ends of the first common recovery passage 18 and 17 in the longitudinal direction are obliquely shifted.

With the flow paths 17 and 18 having such a shape, while reliably supplying ink to the discharge ports 11 located at both ends of the discharge port row 16, each of the ends of the flow paths 17 and 18 and the liquid discharge substrate By increasing the width between the ends of the (100), it is possible to secure the strength of the liquid discharge substrate (100). More specifically, as shown in FIG. 18A, the distance between the right end of the flow path 17 and the right end of the liquid discharge substrate 100 can be set longer, and the left end of the flow path 18 and the liquid discharge The distance between the left end and the left end of the substrate 100 can be set long. In addition, as shown in Fig. 18B, both ends of the first common supply flow passage 17 and the first common recovery flow passage 18 in the longitudinal direction have a shape in which corners are removed. In the case of this example, a chamfered shape is shown, but a round shape may be used. With this shape, when an external force or deformation occurs due to heat, it is possible to suppress the possibility that stress is concentrated at both ends of the first common supply flow path 17 and the first common recovery flow path 18, and thus liquid due to cracks or the like Damage to the discharge substrate 100 can be suppressed.

(Example 5)

19 and 20 are explanatory diagrams showing the liquid discharge unit 300 according to the fifth embodiment of the present invention, and the same reference numerals are given for the same parts as those in the above-described embodiment, omitting the description. 19 is an exploded perspective view showing the liquid discharge unit 300, and FIG. 20 is an exploded plan view showing the liquid discharge unit 300. As shown in FIG.

In this example, as shown in Fig. 19, for the four outlet rows 16 (16A, 16B, 16C, 16D), three first common supply passages 17 (17A, 17B, 17C) and two First common recovery flow path 18 (18A, 18B) are arranged. As shown in Fig. 20, between the discharge port rows 16A and 16B, a recovery flow path 15 common to these rows 16A and 16B is disposed, and the recovery flow path 15 is a first common recovery flow path. He is in communication with (18A). In addition, between the discharge port rows 16B and 16C, a supply passage 14 common to these rows 16B and 16C is disposed, and the supply passage 14 communicates with the first common supply passage 17A. . In addition, between the discharge port rows 16C and 16D, a recovery flow path 15 common to these rows 16C and 16D is disposed, and the recovery flow path 15 is in communication with the first common recovery flow path 18B. . The supply passage 14 of the discharge port row 16A communicates with the first common supply passage 17A, and the supply passage 14 of the discharge port row 16D communicates with the first common supply passage 17C.

In this way, one first common supply passage 17B communicates with the pressure chamber 13 of these outlet rows 16B and 16C through the supply passage 14 common to the outlet rows 16B and 16C. . Further, one first common recovery flow path 18A communicates with the pressure chamber 13 of these discharge port rows 16A and 16B through a recovery flow path 15 common to the discharge port rows 16A and 16B. Similarly, one first common recovery flow path 18B communicates with the pressure chamber 13 of these discharge port rows 16C and 16D via the recovery flow path 15 common to the discharge port rows 16C and 16D.

According to this embodiment, in addition to the effects of the above-described embodiment, the following effects can be obtained.

That is, since two adjacent rows of discharge ports share the first common supply passage 17 and the first common recovery passage 18, the number of partition walls and the number of ink passages between the ink passages can be reduced. Accordingly, it is possible to narrow the space between the discharge port rows 16 and to increase the width of the ink flow path. As a result, a change in the ink circulation flow rate and a change in pressure in each pressure chamber 13 are further suppressed. Thereafter, as compared to the above-described embodiment, the outlet rows 16 are arranged more densely, so that the size of the substrate and the recording head can be reduced. In addition, when the arrangement density of the discharge port rows 16 is the same, the change in the ink circulation flow rate and the pressure change in each pressure chamber 13 are further suppressed, and the first supply port 30 and the first recovery port ( 31) can be reduced. Accordingly, the structure of the ink flow path of the substrate can be simplified.

(Example 6)

21 to 23 are explanatory diagrams showing the liquid discharge unit 300 according to the sixth embodiment of the present invention, and descriptions of parts similar to those of the above-described embodiment are omitted and the same reference numerals are given. 21 is an exploded perspective view showing the liquid discharge unit 300, and FIG. 22 is an exploded plan view showing the liquid discharge unit 300.

In this embodiment, in order to discharge ink of different colors or a plurality of types of ink into one substrate, a discharge port having a discharge port row having discharge ports 51 for the first ink and discharge ports 61 for the second ink Form heat The second flow path layer 23 includes a first common supply flow path 52 for a first ink, a first common supply flow path 62 for a second ink, a first common recovery flow path 53 for the first ink, and A first common recovery flow path 63 for the second ink is provided. In the third flow path layer 24, a supply port 54 for a first ink, a supply port 64 for a second ink, a recovery port 55 for a first ink, and a recovery port for a second ink ( 65) is provided. In the fourth flow path layer 25, a second common supply flow path 56 for the first ink, a second common supply flow path 66 for the second ink, and a third common recovery flow path 57 for the first ink. And a third common recovery passage 67 for the second ink. In the fifth flow path layer 26, a second supply port 58 for the first ink, a second supply port 68 for the second ink, a second recovery port 59 for the first ink, and a second A second recovery port 69 for ink is provided. In the sixth passage layer 27, a third common supply passage 70 for the first ink, a third common supply passage 80 for the second ink, and a third common recovery passage 71 for the first ink. And a third common recovery passage 81 for the second ink.

Each of the first and second inks, as in the first embodiment, is supplied from the third common supply flow paths 70 and 80, and after passing through the corresponding pressure chamber 13, the third common recovery flow path 71, 81).

Similar to the fifth embodiment, one first common supply passage can communicate in common with the pressure chambers of the two outlet rows. Similarly, one first common recovery flow path can communicate in common with the pressure chambers of the two outlet rows. Also, the width of the sixth flow path layer 27 in the second direction may be set larger than the width of the first flow path layer 22 in the second direction.

In this way, even in the recording head for a plurality of colors of inks or a plurality of types of inks, the change and pressure of the ink circulation amount in each pressure chamber without expanding the widths of the first common supply flow path and the first common recovery flow path Can suppress the change of. Therefore, it is possible to record a high-quality image with higher precision by suppressing a decrease in the ink ejection speed and a change in the ink colorant concentration due to evaporation of water in the ink from the ejection port.

(Arrangement relationship between flow paths 52, 53 and flow paths 62, 63)

Arrangement relationship between the first common supply flow path 52 and the first common recovery flow path 53 for the first ink, and the first common supply flow path 62 and the first common recovery flow path 63 for the second ink It is preferable to set as follows.

That is, as shown in FIG. 23, between the first ink discharge port row 16 (1) and the second ink discharge port row 16, (2), the first common recovery flow path 53 and the second The beam width W4 between one common supply flow path 62 is set larger than the beam width W1. When the beam width W4 is set to be large, ink leakage between the first common recovery flow path 53 and the first common supply flow path 62 can be suppressed so that the colors of the ink are not mixed with each other. The beam width W3 and the beam width W4 may be the same or different from each other. In particular, when the beam width W3 between the flow paths for the same ink is set smaller than the beam width W4 between the flow paths for different inks, the pressure loss in the flow path for the flow of ink is reduced, and thus the ink ejection characteristics This can be improved. In this way, since the reverse flow of the ink circulation flow is suppressed, mixing of the colors of the ink can be suppressed while maintaining the pressure in the first common supply flow passage 17 at a negative pressure.

(Example of configuration of liquid discharge head)

24A to 24E are perspective views showing a configuration example having different inkjet recording heads serving as the liquid discharge heads of the present invention.

The recording head of Fig. 24A includes one liquid discharge substrate 100, and the support member 400 and the liquid discharge substrate 100 are sequentially disposed on the first flow path member 500. The recording head is used in a so-called serial scan type inkjet recording apparatus. The recording apparatus conveys the recording operation in which ink is ejected from the discharge port while moving the recording head in the main scanning direction indicated by arrow X, and the recording medium in the sub-scan direction indicated by arrow Y intersecting (orthogonal in this example) with the main scanning direction. An image is recorded on the recording medium by repeating the above operation. The main scanning direction is a direction intersecting (orthogonal in this example) with the first direction in which the discharge port rows 16 extend.

The recording heads in Figs. 24B and 24C are elongate line heads in which a plurality of liquid discharge substrates 100 are arranged in a zigzag shape. In the configuration of FIG. 24B, the first flow path member 500 is disposed in common with respect to the plurality of liquid discharge substrates 100. In the configuration of FIG. 24C, the first flow path members 500 are individually disposed on each of the liquid discharge substrates 100. The first flow path member 500 is disposed on the second flow path member 600. Such a recording head is used in a so-called full-line inkjet recording apparatus. The recording apparatus discharges ink from the recording head at the stop position while continuously conveying the recording medium in the direction indicated by the arrow Y direction intersecting (orthogonal in this example) with the first direction in which the discharge port rows 16 extend. , Images are continuously recorded on the recording medium.

The recording heads in Figs. 24D and 24E are elongate line heads in which liquid ejection substrates 100 are arranged in a row, and are used in a so-called full-line inkjet recording apparatus. In the configuration of FIG. 24D, the first flow path member 500 is disposed in common with respect to the plurality of liquid discharge substrates 100. In the configuration of FIG. 24E, the first flow path member 500 is individually arranged for each liquid discharge substrate 100. The first flow path member 500 is disposed on the second flow path member 600. It is preferable that the liquid discharge substrate 100 of such a recording head is formed in the shape of the fourth embodiment.

In such various recording heads, by generating an ink circulation flow as described above, it is possible to record high-quality images with high precision while suppressing a decrease in ink ejection speed and a change in ink colorant concentration due to evaporation of water in the ink from the ejection port.

(Configuration example of liquid discharge device)

25A to 25C are diagrams showing a configuration example having different inkjet recording apparatuses employing the liquid ejection apparatus of the present invention.

The inkjet recording apparatus of Fig. 25A is a serial scan type recording apparatus using a recording head having the configuration of Fig. 24A as the recording head 43. The chassis 47 is formed of a plurality of plate-shaped metal members having a predetermined rigidity, and forms a frame of a recording apparatus. The chassis 47 is assembled with a feed unit 41, a conveyance unit 42, and a carriage 46 that is mounted with a recording head 43 and is movable in the main scanning direction indicated by an arrow X. The main scanning direction is a direction intersecting (orthogonal in this example) with the extending direction of the discharge port row in the recording head 43. The feeding unit 41 automatically feeds the sheet-shaped recording medium (not shown) into the recording device, and the conveying unit 42 shows the recording medium fed one by one from the feeding unit 41 by a sub-scan indicated by arrow Y. It conveys in the direction. The sub-scan direction is a direction that intersects (orthogonal in this example) to the main scan direction. Such a recording apparatus performs a recording operation of discharging ink from the discharge port of the recording head 43 while moving the recording head 43 together with the carriage 46 in the main scanning direction, and a conveying operation of conveying the recording medium in the sub-scanning direction. By repeating, an image is recorded on the recording medium. For the recording head 43, ink is supplied from an ink tank (not shown).

The inkjet recording apparatus in Fig. 25B is a full-line recording apparatus using the elongated recording head 120 described in Figs. 24B, 24C, 24D, and 24E, and a sheet (recording medium) 201 is indicated by an arrow. It is provided with a conveying mechanism 202 which conveys continuously in the direction indicated by Y. As the conveying mechanism 202, a structure using a conveying roller or the like can be used instead of this example using a conveying belt. In this example, as the recording head 120, four recording heads 120Y, 120M, 120C, and 120B that eject inks of yellow (Y), magenta (M), cyan (C) and black (Bk) are provided. do. The corresponding ink is supplied to the recording head 120 (120Y, 120M, 120C, 120B). When ink is discharged from the recording head 120 at a stop position while continuously conveying the sheet 201 in the direction indicated by arrow Y, color images can be continuously recorded on the sheet 201.

25C is an explanatory diagram showing an ink supply system for the recording heads 43 and 120. FIG. After the ink in the first ink tank 44 is supplied to the third common supply flow path 36 of the recording heads 43 and 120, after passing through the pressure chamber 13, the third common recovery flow path 37 It is recovered from the second ink tank 45. As a method of generating an ink circulation flow in the recording heads 43 and 120, for example, a method of using a head difference between the first ink tank 44 and the second ink tank 45 is known. Alternatively, a method of generating a pressure difference between the first ink tank 44 and the second ink tank 45 by controlling the internal pressure of the first ink tank 44 and the second ink tank 45 is known. . Further, a method of generating an ink circulation flow using a pump or the like is known. The configuration of the ink supply system and the method of generating the ink circulation flow are not limited to this example and can be set arbitrarily. As long as the differential pressure generator capable of generating a pressure difference required for circulation of the ink in the pressure chamber can be configured, the configuration and method do not become a problem.

In such a recording apparatus, by generating an ink circulation flow in the recording head, it is possible to record a high-quality image with high precision while suppressing a decrease in the ink ejection speed and a change in the ink colorant concentration due to evaporation of water in the ink from the ejection port.

(1st application example)

26 to 38 are diagrams showing a first application example to which the present invention is applicable.

(Description of inkjet recording device)

26 is a diagram showing a schematic configuration of a liquid ejection apparatus of the present invention that ejects a liquid, particularly an inkjet recording apparatus (hereinafter also referred to as a recording apparatus) 1000 that ejects ink to record an image. The recording apparatus 1000 includes a conveying unit 1 for conveying the recording medium 2, and a line-shaped (page-wide type) liquid discharge head 3 disposed substantially orthogonal to the conveying direction of the recording medium 2. ). Then, the recording apparatus 1000 is a line-type recording apparatus that continuously or intermittently conveys the recording medium 2, ejecting ink onto the relatively moving recording medium 2, and continuously records images in one pass. The liquid discharge head 3 includes a negative pressure control unit 230 that controls the pressure (negative pressure) in the circulation path, a liquid supply unit 220 communicating with the negative pressure control unit 230, and ink of the liquid supply unit 220. A liquid connection part 111 serving as a supply port and an ink discharge port, and a casing 380 are provided. The recording medium 2 is not limited to a cut sheet, but may be a continuous roll medium. The liquid discharge head 3 can print a full color image with cyan (C), magenta (M), yellow (Y), and black (K) inks, and supplies liquid to the liquid discharge head 3 It is fluidly connected to a liquid supply member serving as a supply path, a main tank, and a buffer tank (see Fig. 27 to be described below). Further, to the liquid discharge head 3, a control unit that supplies electric power to the liquid discharge head 3 and transmits a discharge control signal is electrically connected. The liquid path and the electric signal path in the liquid discharge head 3 will be described later.

The recording apparatus 1000 is an inkjet recording apparatus that circulates a liquid such as ink between a tank and a liquid discharge head 3 to be described later. The circulation type is a first circulation type in which liquid is circulated by the operation of two circulation pumps (for high pressure and low pressure) on the downstream side of the liquid discharge head 3 and two types of the upstream side of the liquid discharge head 3. It includes a second circulation type in which liquid circulates by operation of a circulation pump (for high pressure and low pressure). Hereinafter, the first circulation form and the second circulation form of this circulation will be described.

(Explanation of the first circulation form)

Fig. 27 is a schematic diagram showing a first circulation form of a circulation path applied to the recording apparatus 1000 of this application example. The liquid discharge head 3 is fluidly connected to a first circulation pump (high pressure side) 1001, a first circulation pump (low pressure side) 1002 and a buffer tank 1003. In addition, in Fig. 27, in order to simplify the description, a path through which ink of one color of cyan (C), magenta (M), yellow (Y), and black (K) flows is shown. However, in practice, a four-color circulation path is provided in the liquid discharge head 3 and the recording apparatus body.

In the first circulation mode, the ink in the main tank 1006 is supplied to the buffer tank 1003 by the replenishment pump 1005, and then the liquid is discharged through the liquid connection part 111 by the second circulation pump 1004. It is supplied to the liquid supply unit 220 of the head 3. After that, the ink adjusted to two different negative pressures (high pressure and low pressure) by the negative pressure control unit 230 connected to the liquid supply unit 220 is divided into two flow paths having a high pressure and a low pressure, and circulates. The ink in the liquid discharge head 3 is liquid discharged by the action of the first circulation pump (high pressure side) 1001 and the first circulation pump (low pressure side) 1002 on the downstream side of the liquid discharge head 3 It circulates inside the head, is discharged from the liquid discharge head 3 through the liquid connection part 111, and returns to the buffer tank 1003.

The buffer tank 1003 as a sub-tank is connected to the main tank 1006 and has an atmospheric communication port (not shown) that communicates the inside of the tank 1003 with the outside, so that bubbles in the ink can be discharged to the outside. have. A replenishment pump 1005 is provided between the buffer tank 1003 and the main tank 1006. The replenishment pump 1005 transfers the ink from the main tank 1006 to the buffer tank 1003 after the ink is consumed by the discharge (discharge) of ink from the discharge port of the liquid discharge head 3 in the recording operation and the suction recovery operation. ).

The two first circulation pumps 1001 and 1002 draw liquid from the liquid connection part 111 of the liquid discharge head 3 so that the liquid flows into the buffer tank 1003. As the first circulation pump, a positive displacement pump having a quantitative liquid transfer capability is preferable. Specifically, a tube pump, a gear pump, a diaphragm pump, and a syringe pump can be illustrated. However, for example, a general constant flow valve or a general relief valve may be disposed at the outlet of the pump to secure a predetermined flow rate. When the liquid discharge head 3 is driven, the first circulation pump (high pressure side) 1001 and the first circulation pump (low pressure side) 1002 operate, so that ink is supplied to the common supply flow path 211 and the common recovery flow path. Flow through 212 at a predetermined flow rate. Since the ink flows in this way, the temperature of the liquid discharge head 3 during the recording operation is maintained at an optimum temperature. The predetermined flow rate when the liquid discharge head 3 is driven is preferably set to be equal to or greater than the flow rate at which the temperature difference between the recording element substrates 10 in the liquid discharge head 3 does not affect the recording quality. First of all, when an excessively large flow rate is set, the negative pressure difference between the recording element substrates 10 increases due to the influence of the pressure loss of the flow path in the liquid discharge unit 300, resulting in a non-uniform concentration. Therefore, it is preferable to set the flow rate in consideration of the difference in temperature and negative pressure between the recording element substrates 10.

The negative pressure control unit 230 is provided in a path between the second circulation pump 1004 and the liquid discharge unit 300. The negative pressure control unit 230, even when the flow rate of ink in the circulation system changes due to a difference in the amount of ink discharged per unit area, etc., the pressure on the downstream side (that is, the liquid discharge unit 300 side) than the negative pressure control unit 230 It works to keep it at a predetermined pressure. As the two negative pressure control mechanisms constituting the negative pressure control unit 230, any mechanism can be used as long as the pressure on the downstream side of the negative pressure control unit 230 can be controlled within a predetermined range or less from a desired set pressure. As an example, a mechanism such as a so-called "pressure pressure regulator" can be employed. In the circulation passage of this application example, the upstream side of the negative pressure control unit 230 is pressurized by the second circulation pump 1004 via the liquid supply unit 220. With this configuration, the influence of the head pressure on the liquid discharge head 3 of the buffer tank 1003 can be suppressed, so that the degree of freedom in the layout of the buffer tank 1003 of the recording apparatus 1000 can be increased.

As the second circulation pump 1004, a turbo type pump or a positive displacement pump can be used as long as a predetermined head pressure or more can appear within the range of the ink circulation flow rate used when the liquid discharge head 3 is driven. Specifically, a diaphragm pump can be used. In addition, for example, instead of the second circulation pump 1004, a head tank disposed to have a predetermined head difference with respect to the negative pressure control unit 230 may be used.

As shown in Fig. 27, the negative pressure control unit 230 includes two negative pressure adjustment mechanisms each having a different control pressure. Of the two negative pressure adjustment mechanisms, the relatively high pressure side (indicated as "H" in FIG. 27) and the relatively low pressure side (indicated as "L" in FIG. 27), through the liquid supply unit 220, the liquid discharge unit They are respectively connected to the common supply flow path 211 and the common recovery flow path 212 in the 300. The liquid discharge unit 300 includes a common supply flow path 211, a common recovery flow path 212, and an individual flow path 215 communicating with the recording element substrate (individual supply flow path 213 and individual recovery flow path 214). Provided. The negative pressure control mechanism H is connected to the common supply flow path 211, the negative pressure control mechanism L is connected to the common recovery flow path 212, and a differential pressure is formed between the two common flow paths 211 and 212. In addition, since the individual flow path 215 communicates with the common supply flow path 211 and the common recovery flow path 212, a part of the liquid is transferred from the common supply flow path 211 to the flow path formed inside the recording element substrate 10. A flow flowing in the common recovery flow path 212 (flow shown in the direction of an arrow in FIG. 27) occurs.

In this way, the liquid discharge unit 300 has a flow through which a part of the liquid passes through the recording element substrate 10 while the liquid flows through the common supply flow path 211 and the common recovery flow path 212. Accordingly, heat generated by the recording element substrate 10 can be discharged to the outside of the recording element substrate 10 by ink flowing through the common supply flow path 211 and the common recovery flow path 212. With this configuration, when an image is recorded by the liquid discharge head 3, the flow of ink can occur even in a discharge or pressure chamber that does not discharge liquid. Accordingly, the thickening of the ink can be suppressed in a manner that lowers the viscosity of the thickened ink in the discharge port. Further, the thickened ink or foreign matter in the ink can be discharged toward the common recovery flow path 212. For this reason, the liquid discharge head 3 of this application example can record high-quality images at high speed.

(Explanation of the second circulation form)

FIG. 28 is a schematic diagram showing a second circulation form, which is a circulation form different from the first circulation form among circulation paths applied to the recording apparatus of this application example. The main difference from the first circulation type is that both of the two negative pressure control mechanisms constituting the negative pressure control unit 230 control the pressure upstream from the negative pressure control unit 230 within a predetermined range from the desired set pressure. Point. Further, another difference from the first circulation form is that the second circulation pump 1004 acts as a negative pressure source for reducing the pressure on the downstream side of the negative pressure control unit 230. In addition, another difference is that the first circulation pump (high pressure side) 1001 and the first circulation pump (low pressure side) 1002 are disposed on the upstream side of the liquid discharge head 3, and the negative pressure control unit 230 It is arranged on the downstream side of this liquid discharge head 3.

In the second circulation mode, the ink in the main tank 1006 is supplied to the buffer tank 1003 by the replenishment pump 1005. After that, the ink is divided into two flow paths, and circulates in two flow paths on the high pressure side and the low pressure side by the action of the negative pressure control unit 230 provided in the liquid discharge head 3. The ink separated into two flow paths on the high-pressure side and the low-pressure side is passed through the liquid connection part 111 by the action of the first circulation pump (high pressure side) 1001 and the first circulation pump (low pressure side) 1002. It is supplied to the liquid discharge head 3. Thereafter, ink circulating in the liquid discharge head by the action of the first circulation pump (high pressure side) 1001 and the first circulation pump (low pressure side) 1002 is transferred to the negative pressure control unit 230 and the liquid connection part 111. It is discharged from the liquid discharge head 3 through ). The discharged ink is returned to the buffer tank 1003 by the second circulation pump 1004.

In the second circulation mode, the negative pressure control unit 230 is on the upstream side of the negative pressure control unit 230 (that is, the liquid discharge unit 300) even when a change in the flow rate occurs due to a change in the ink discharge amount per unit area. Side) to stabilize the pressure change within a predetermined range. In the circulation passage of this application example, the downstream side of the negative pressure control unit 230 is pressurized by the second circulation pump 1004 via the liquid supply unit 220. According to this configuration, since the influence of the head pressure of the buffer tank 1003 on the liquid discharge head 3 can be suppressed, the layout of the buffer tank 1003 in the recording apparatus 1000 can have many options. have. Instead of the second circulation pump 1004, a head tank arranged to have a predetermined head difference with respect to the negative pressure control unit 230 may be used, for example. In the second circulation form, like the first circulation form, the negative pressure control unit 230 includes two negative pressure control mechanisms each having a different control pressure. Of the two negative pressure adjustment mechanisms, the high-pressure side (indicated by "H" in Fig. 28) and the low-pressure side (indicated by "L" in Fig. 28) are common in the liquid discharge unit 300 through the liquid supply unit 220, respectively. It is connected to the supply flow path 211 and the common recovery flow path 212. When the pressure of the common supply flow path 211 is set higher than the pressure of the common recovery flow path 212 by the two negative pressure adjustment mechanisms, the common supply through the individual flow paths 215 and the flow paths formed inside the recording element substrate 10 A liquid flow is formed from the flow path 211 to the common recovery flow path 212.

In this second circulation type, the same liquid flow as the first circulation type can be obtained in the liquid discharge unit 300, but there are two advantages different from that of the first circulation type. As a first advantage, in the second circulation mode, since the negative pressure control unit 230 is disposed on the downstream side of the liquid discharge head 3, dust and foreign matter generated by the negative pressure control unit 230 are prevented from ), there is little risk of inflow. As a second advantage, in the second circulation type, the maximum value of the required flow rate for the liquid supplied from the buffer tank 1003 to the liquid discharge head 3 is smaller than that of the first circulation type. The reason for this is as follows.

In the case of circulation in the recording standby state, the sum of the flow rates of the common supply flow path 211 and the common recovery flow path 212 is set to the flow rate A. The value of the flow rate A is defined as the minimum flow rate required to adjust the temperature of the liquid discharge head 3 in the recording standby state so that the temperature difference in the liquid discharge unit 300 is within a desired range. Further, the discharge flow rate obtained when ink is discharged from all discharge ports of the liquid discharge unit 300 (total discharge state) is defined as flow rate F (discharge amount per discharge port × discharge frequency per unit time × number of discharge ports).

Fig. 29 is a schematic diagram showing the difference in the amount of ink flowing into the liquid discharge head 3 between the first circulation mode and the second circulation mode. Part (a) of FIG. 29 shows the standby state of the first circulation type, and part (b) of FIG. 29 shows the entire discharge state of the first circulation type. Parts (c) to (f) of Fig. 29 show the second circulation form. Here, parts (c) and (d) of FIG. 29 show the case where the flow rate F is less than the flow rate A, and parts (e) and (f) of FIG. 29 show the case where the flow rate F is greater than the flow rate A. As such, the flow rates in the standby state and the entire discharge state are shown.

In the case of the first circulation type in which the first circulation pump 1001 and the first circulation pump 1002 each having a quantitative liquid transfer capability are disposed on the downstream side of the liquid discharge head 3 (Fig. 29(a)) And (b)), the total set flow rate of the first circulation pump 1001 and the first circulation pump 1002 is a flow rate A. The temperature in the liquid discharge unit 300 in the standby state can be managed by the flow rate A. And, in the case of the whole discharge state of the liquid discharge head 3, the total flow volume of the 1st circulation pump 1001 and the 1st circulation pump 1002 becomes the flow rate A. However, the maximum flow rate supplied to the liquid discharge head 3 is obtained so that the flow rate F consumed by the total discharge is added to the flow rate A of the total flow rate by the action of the negative pressure generated by the discharge of the liquid discharge head 3. Lose. Therefore, the maximum value of the supply amount to the liquid discharge head 3 satisfies the relationship of {(flow rate A) + (flow rate F)} because the flow rate F is added to the flow rate A (part (b) of FIG. 29). .

On the other hand, in the case of the second circulation type in which the first circulation pump 1001 and the first circulation pump 1002 are disposed on the upstream side of the liquid discharge head 3 (Fig. 29(c) and (d)), The amount of supply to the liquid discharge head 3 required in the recording standby state becomes the flow rate A as in the first circulation mode. Therefore, when the flow rate A is higher than the flow rate F in the second circulation type in which the first circulation pump 1001 and the first circulation pump 1002 are disposed on the upstream side of the liquid discharge head 3 (Fig. 29(c)) And (d) part), even in the entire discharge state, the amount of supply to the liquid discharge head 3 is sufficient at the flow rate A. At that time, the discharge flow rate of the liquid discharge head 3 satisfies the relationship of {(flow rate A)-(flow rate F)} (part (d) in Fig. 29). However, in the case where the flow rate F is greater than the flow rate A (parts (e) and (f) of Fig. 29), when the flow rate of the liquid supplied to the liquid discharge head 3 in the entire discharge state becomes the flow rate A, the flow rate is It becomes insufficient. Therefore, when the flow rate F is larger than the flow rate A, the supply amount to the liquid discharge head 3 needs to be set to the flow rate F. At that time, since the flow rate F is consumed by the liquid discharge head 3 in the entire discharge state, the flow rate of the liquid discharged from the liquid discharge head 3 becomes almost zero (Fig. 29(f)). Further, when the flow rate F is greater than the flow rate A, the liquid is discharged, but when it is not discharged in the entire discharge state, the liquid sucked by the amount consumed by the discharge among the flow rate F is discharged from the liquid discharge head 3. The liquid reduced by the amount consumed by the discharge from the flow rate F is discharged from the liquid discharge head 3. Further, when the flow rate A and the flow rate F are equal to each other, the flow rate A (or the flow rate F) is supplied to the liquid discharge head 3, and the flow rate F is consumed by the liquid discharge head 3. For this reason, the flow rate discharged from the liquid discharge head 3 becomes almost zero.

As described above, in the case of the second circulation type, the sum of the flow rates set for the first circulation pump 1001 and the first circulation pump 1002, that is, the maximum value of the required supply flow rate, is the larger of the flow rate A and the flow rate F. Becomes. For this reason, as long as the liquid discharge unit 300 having the same configuration is used, the maximum value (flow rate A or flow rate F) of the required supply amount in the second circulation type is the maximum value of the supply flow rate required in the first circulation type {(flow rate It becomes smaller than A)+(flow rate F)}.

Thus, in the case of the second circulation type, the degree of freedom of the applicable circulation pump is increased. For example, a circulation pump having a simple configuration and low cost can be used, or a load of a cooler (not shown) provided in the main body side path can be reduced. Therefore, there is an advantage of being able to reduce the cost of the recording apparatus. This advantage increases as the value of the flow rate A or the flow rate F is relatively large in the line head. Therefore, among the line heads, a line head having a long length in the longitudinal direction is advantageous.

On the other hand, the first circulation form has an advantage over the second circulation form. That is, in the second circulation type, since the flow rate of the liquid flowing through the liquid discharge unit 300 in the recording standby state is the maximum, an image with a small discharge amount per unit area (hereinafter referred to as a low-duty image). The higher the value is, the higher the negative pressure is applied to the discharge port. For this reason, when the flow path width is narrow and the negative pressure is high, a high negative pressure is applied to the discharge port in a low duty image where unevenness is likely to appear. Accordingly, there is a concern that the recording quality may deteriorate with an increase in the number of so-called satellite droplets discharged according to the main droplet of ink.

On the other hand, in the case of the first circulation type, since a high negative pressure is applied to the discharge port when an image with a large discharge amount per unit area (hereinafter, also referred to as a high-duty image) is formed, the satellite liquid for the image The advantage is that the enemy's influence is small. It may be desirable to select two circulation types in consideration of the specifications of the liquid discharge head and the recording device main body (discharge flow rate F, minimum circulation flow rate A, and flow path resistance in the head).

(Explanation of the third circular form)

Fig. 48 is a schematic diagram showing a third circulation form, which is one of the circulation paths used in the recording apparatus of this embodiment. Description of the same functions and configurations as those of the first and second circulation paths is omitted, and only differences are described.

In this circulation path, liquid is supplied into the liquid discharge head 3 from three positions including two positions of the central portion of the liquid discharge head 3 and one end side of the liquid discharge head 3. The liquid flowing from the common supply flow path 211 to each pressure chamber 23 is recovered by the common recovery flow path 212 and is recovered from the recovery opening at the other end of the liquid discharge head 3 to the outside. The individual flow path 215 is in communication with the common supply flow path 211 and the common recovery flow path 212, and the pressure disposed in the recording element substrate 10 and the recording element substrate 10 in the path of the individual flow path 215 A thread 23 is provided. Accordingly, a part of the liquid flowing from the first circulation pump 1002 passes through the pressure chamber 23 of the recording element substrate 10 from the common supply flow path 211 and flows into the common recovery flow path 212 (Fig. 48). This causes a pressure difference between the pressure adjustment mechanism H connected to the common supply flow path 211 and the pressure adjustment mechanism L connected to the common recovery flow path 212, and the first circulation pump 1002 212).

In this way, in the liquid discharge unit 300, the flow of the liquid passing through the common recovery flow path 212 and the common supply flow path 211 through the pressure chamber 23 in each recording element substrate 10 are common. The flow of the liquid flowing in the recovery flow path 212 occurs. Therefore, while suppressing pressure loss, heat generated by each recording element substrate 10 can be discharged to the outside of the recording element substrate 10 by flow from the common supply flow path 211 to the common recovery flow path 212. I can. Further, according to this circulation path, it is possible to reduce the number of pumps that are liquid transport units compared to the first and second circulation paths.

(Description of the liquid discharge head configuration)

The configuration of the liquid discharge head 3 according to the first application example will be described. 30A and 30B are perspective views showing the liquid discharge head 3 according to this application example. In the liquid discharge head 3, 15 recording element substrates 310 capable of discharging inks of four colors of cyan (C), magenta (M), yellow (Y), and black (K) are arranged in series. It is a line type liquid discharge head that becomes (in-line arrangement). As shown in Fig. 30A, the liquid discharge head 3 includes a recording element substrate 310, a signal input terminal 91, and a power supply terminal 92. These terminals 91 and 92 are electrically connected to the recording element board 310 via the flexible circuit board 40 and the electric wiring board 90. The signal input terminal 91 and the power supply terminal 92 are electrically connected to the control unit of the recording apparatus 1000 to supply a discharge driving signal and power required for discharge to the recording element substrate 310. When wiring is integrated by an electric circuit in the electric wiring board 90, the number of the signal output terminals 91 and the power supply terminals 92 can be made smaller than the number of the recording element board 310. Thereby, the number of electrical connecting parts to be separated when assembling the liquid discharge head 3 in the recording apparatus 1000 or when replacing the liquid discharge head is reduced. As shown in Fig. 30B, the liquid connection portions 111 provided at both ends of the liquid discharge head 3 are connected to the liquid supply system of the recording apparatus 1000. As shown in FIG. Accordingly, four colors of inks including cyan (C), magenta (M), yellow (Y), and black (K) are supplied from the supply system of the recording apparatus 1000 to the liquid discharge head 3, and Ink passing through the discharge head 3 is recovered by the supply system of the recording apparatus 1000. In this way, inks of different colors can circulate through the path of the recording apparatus 1000 and the path of the liquid discharge head 3.

31 is an exploded perspective view showing a component or unit constituting the liquid discharge head 3. A liquid discharge unit 300, a liquid supply unit 220, and an electric wiring board 90 are attached to the casing 380. The liquid supply unit 220 is provided with a liquid connection 111 (see Fig. 28). In addition, in order to remove foreign substances in the supplied ink, a filter 221 (refer to FIGS. 27 and 28) for various colors communicating with the opening of the liquid connection part 111 is provided inside the liquid supply unit 220. have. The two liquid supply units 220 are provided with filters 221 corresponding to two colors, respectively. In the first circulation type as shown in FIG. 27, the liquid passing through the filter 221 is supplied to the negative pressure control unit 230 disposed above the liquid supply unit 220 disposed corresponding to each color. The negative pressure control unit 230 is a unit including negative pressure control valves corresponding to different colors. The change in pressure loss inside the supply system of the recording device 1000 (supply system on the upstream side of the liquid discharge head 3) caused by a change in the flow rate of the liquid is caused by the function of the spring member or valve provided inside. Greatly reduced. Thereby, the negative pressure control unit 230 can stabilize the negative pressure change on the downstream side (liquid discharge unit 300 side) than the pressure control unit within a predetermined range. As described in FIG. 27, two negative pressure control valves corresponding to each color are incorporated in the negative pressure control unit 230. The two negative pressure control valves are each set to a different control pressure. Here, the high pressure side of the two negative pressure control valves communicates with the common supply flow path 211 (see Fig. 27) in the liquid discharge unit 300 via the liquid supply unit 220, and the low pressure side of the two negative pressure control valves is The liquid supply unit 220 communicates with the common recovery flow path 212 (see FIG. 27).

The casing 380 includes a liquid discharge unit support part 381 and an electric wiring board support part 82, and secures the rigidity of the liquid discharge head 3 while supporting the liquid discharge unit 300 and the electric wiring board 90 Are doing. The electric wiring board support part 82 is used to support the electric wiring board 90, and is fixed to the liquid discharge unit support part 381 by screws. The liquid discharge unit support part 381 is used to correct the warpage or deformation of the liquid discharge unit 300 to ensure the relative positional accuracy of the recording element substrate 310. Thus, streaks and spots in images recorded on the medium are suppressed. For this reason, it is preferable that the liquid discharge unit support part 381 has sufficient rigidity. As the material, a metal such as SUS or aluminum, or a ceramic such as alumina is preferable. The liquid discharge unit support portion 381 is provided with openings 83 and 84 into which the joint rubber 100 is inserted. The liquid supplied from the liquid supply unit 220 is guided to the third flow path member 370 constituting the liquid discharge unit 300 through the joint rubber 100.

The liquid discharge unit 300 includes a plurality of discharge modules 200 and a flow path member 210, and a cover member 130 is attached to a surface of the liquid discharge unit 300 near the recording medium. Here, the cover member 130 is a member having a photo frame-shaped surface provided with an elongated opening 131 as shown in FIG. 31, and from the opening 131, the recording element substrate included in the discharge module 200 ( 310) and the sealing member 110 (see Fig. 35A to be described later) are exposed. The frame around the opening 131 serves as a contact surface of the cap member covering the liquid discharge head 3 in the recording standby state. For this reason, it is preferable to form an enclosed space in a capped state by applying an adhesive, a sealing material, and a filler along the periphery of the opening 131 to fill the irregularities or gaps on the discharge port surface of the liquid discharge unit 300.

Next, the configuration of the flow path member 210 included in the liquid discharge unit 300 will be described. As shown in Fig. 31, the flow path member 210 is obtained by laminating the first flow path member 50, the second flow path member 60, and the third flow path member 370, from the liquid supply unit 220. The supplied liquid is distributed to the discharge module 200. Further, the flow path member 210 is a flow path member that returns the liquid recirculated from the discharge module 200 to the liquid supply unit 220. The flow path member 210 is fixed to the liquid discharge unit support portion 381 by screws, thereby suppressing the bending or deformation of the flow path member 210.

Parts (a) to (f) of Fig. 32 are diagrams showing the front and rear surfaces of the first to third flow path members. Part (a) of FIG. 32 shows the surface of the first flow path member 50 on which the discharge module 200 is mounted, and part (f) of FIG. 32 is a third, in which the liquid discharge unit support part 381 contacts. It shows the surface of the flow path member 370. The first flow path member 50 and the second flow path member 60 are joined to each other so that portions shown in (b) and (c) of Figs. 32 corresponding to the contact surfaces of the flow path members 50 and 60 face each other. . The second flow path member 60 and the third flow path member 370 are joined to each other so that portions shown in (d) and (e) of FIG. 32 corresponding to the contact surfaces of the flow path members 60 and 370 face each other. . When the second flow path member 60 and the third flow path member 370 are joined to each other, eight common flow paths 211a, 211b, 211c, 211d, 212a, 212b, 212c, 212d extending in the longitudinal direction of the flow path member Is formed by the common flow path grooves 362 and 371 of the flow path member. Accordingly, a set of the common supply flow path 211 and the common recovery flow path 212 is formed in the flow path member 210 to correspond to each color. Ink is supplied to the liquid discharge head 3 from the common supply flow path 211, and the ink supplied to the liquid discharge head 3 is recovered by the common recovery flow path 212. The communication port 72 of the third flow path member 370 (see Fig. 32 (f)) is in communication with the corresponding hole of the joint rubber 100, and the liquid supply unit 220 (see Fig. 31) And fluid connection. The bottom surface of the common flow path groove 362 of the second flow path member 60 includes a plurality of communication ports 361 (communication ports 361-1 communicating with the common supply flow path 211 and a common recovery flow path 212). It is provided with a communication port (361-2) to communicate. This communication port 361 communicates with one end of the corresponding individual flow path groove 352 of the first flow path member 50. The other end of the individual flow path groove 352 of the first flow path member 50 has a communication port 351 and is fluidly connected to the discharge module 200 through the communication port 351. By means of the individual flow path grooves 352, the flow path can be provided densely on the center side of the flow path member.

It is preferable that the first to third flow path members are formed of a material having corrosion resistance to liquid and a low coefficient of linear expansion. As a material, for example, inorganic fillers such as fine silica particles or fibers on a base material such as alumina, LCP (liquid crystal polymer), PPS (polyphenyl sulfide), PSF (polysulfone), or modified PPE (polyphenylene ether). A composite material (resin) obtained by adding can be suitably used. As a method of forming the flow path member 210, three flow path members may be stacked and bonded to each other. When the resin composite material is selected as the material, a bonding method using welding can be used.

FIG. 33 shows a portion α of the portion (a) of FIG. 32, and is formed by bonding the first to third flow path members, viewed from the surface of the first flow path member 50, on which the discharge module 200 is mounted. It is a partially enlarged perspective view showing a flow path in one flow path member 210. The common supply flow path 211 and the common recovery flow path 212 are formed so that the common supply flow path 211 and the common recovery flow path 212 are alternately arranged from flow paths at both ends. Here, the connection relationship between each flow path in the flow path member 210 will be described.

In the flow path member 210, a common supply flow path 211 (211a, 211b, 211c, 211d) and a common recovery flow path 212 (212a, 212b, 212c, 212d) extending in the longitudinal direction of the liquid discharge head 3 Is provided for each color. Individual supply flow paths 213 (213a, 213b, 213c, 213d) formed by individual flow path grooves 352 are connected to a common supply flow path 211 of each color through a communication port 361. In addition, the individual recovery flow paths 214 (214a, 214b, 214c, 214d) formed by the individual flow path grooves 352 are connected to the common recovery flow path 212 of each color through a communication port 361. With such a flow path configuration, ink can be intensively supplied from the common supply flow path 211 to the recording element substrate 310 located at the center of the flow path member through the individual supply flow path 213. Further, ink can be recovered from the recording element substrate 310 to the common recovery path 212 through the individual recovery path 214.

34 is a cross-sectional view taken along line XXXIV-XXXIV in FIG. 33; The individual recovery flow paths 214a and 214c are in communication with the discharge module 200 through a communication port 351. In FIG. 34, only the individual recovery flow paths 214a and 214c are shown, but in another cross section, the individual supply flow path 213 and the discharge module 200 are in communication with each other as shown in FIG. 33. Ink from the first flow path member 50 is supplied to the recording element 315 provided on the recording element substrate 310 to the support member 330 and the recording element substrate 310 included in each ejection module 200 A flow path is provided. Further, the support member 330 and the recording element substrate 310 are provided with flow paths for recovering (recirculating) a part or all of the liquid supplied to the recording element 315 to the first flow path member 50.

Here, the common supply passage 211 of each color is connected through the negative pressure control unit 230 (high pressure side) and the liquid supply unit 220 of the corresponding color, and the common recovery passage 212 is a negative pressure control unit ( 230) (low pressure side) and the liquid supply unit 220 is connected. A differential pressure (pressure difference) is generated between the common supply flow path 211 and the common recovery flow path 212 by the negative pressure control unit 230. For this reason, as shown in Figs. 33 and 34, in the liquid discharge head of this application example having flow paths connected to each other, the common supply flow path 211, the individual supply flow path 213, the recording element substrate 310, and individual Liquid flows of each color occur in the order of the recovery flow path 214 and the common recovery flow path 212.

(Description of the discharge module)

Fig. 35A is a perspective view showing one discharge module 200, and Fig. 35B is an exploded view thereof. As a manufacturing method of the discharge module 200, first, the recording element substrate 310 and the flexible circuit board 40 are adhered onto the support member 330 provided with the liquid communication port 31. Thereafter, the terminal 316 on the recording element substrate 310 and the terminal 341 on the flexible circuit board 40 are electrically connected to each other by wire bonding, and the wire bonding portion (electrical connection portion) is connected to a sealing member ( 110). The terminal 342 on the side opposite to the recording element substrate 310 of the flexible circuit board 40 is electrically connected to the connection terminal 93 (see FIG. 31) of the electric wiring board 90. Since the support member 330 serves as a support for supporting the recording element substrate 310 and as a flow path member for fluid communication between the recording element substrate 310 and the flow path member 210, the support member 330 has a plan view. While having high and sufficiently high reliability, it is preferable to be bonded to the recording element substrate. As a material, alumina or resin is preferable, for example.

(Description of the structure of the recording element substrate)

FIG. 36A is a plan view showing a surface of the recording element substrate 310 on which the discharge port 313 is provided, FIG. 36B is an enlarged view of portion A in FIG. 36A, and FIG. 36C is a plan view showing the rear surface of FIG. 36A. Here, the configuration of the recording element substrate 310 of this application example will be described. As shown in Fig. 36A, the discharge port forming member 312 of the recording element substrate 310 is provided with four rows of discharge ports corresponding to inks of different colors. In addition, the extending direction of the discharge port row of the discharge port 313 is referred to as "discharge port row direction". As shown in FIG. 36B, a recording element 315 serving as a discharge energy generating element for discharging a liquid by thermal energy is disposed at a position corresponding to each discharge port 313. As shown in FIG. A pressure chamber 323 for providing a recording element 315 is formed by the partition wall 22. The recording element 315 is electrically connected to the terminal 316 by an electric wiring (not shown) provided on the recording element substrate 310. The recording element 315 is heated based on a pulse signal input from the control circuit of the recording apparatus 1000 through the electric wiring board 90 (see Fig. 31) and the flexible circuit board 40 (see Fig. 35B). Boil the liquid. The liquid is discharged from the discharge port 313 by the foaming force generated by boiling. As shown in Fig. 36B, a liquid supply path 318 extends on one side along each discharge port row, and a liquid recovery path 319 extends on the other side along the discharge port rows. The liquid supply path 318 and the liquid recovery path 319 are flow paths extending in the direction of the discharge port column provided on the recording element substrate 310, and communicate with the discharge port 313 through the supply port 317a and the recovery port 317b. Has been.

As shown in FIG. 36C, a sheet-shaped cover plate (cover member) 20 is stacked on the rear surface of the surface of the recording element substrate 310 where the discharge port 313 is provided, and the cover plate 20 has a liquid A plurality of openings 20A communicating with the supply path 318 and the liquid recovery path 319 are formed. In this application example, the cover plate 20 is provided with three openings 20A for each liquid supply path 318 and two openings 20A for each liquid recovery path 319. As shown in FIG. 36B, the opening 20A of the cover plate 20 is in communication with the communication port 351 shown in the portion (a) of FIG. 32. It is preferable that the cover plate 20 has sufficient corrosion resistance to liquid. From the viewpoint of preventing color mixing, the opening shape and opening position of the opening 20A need to have high precision. For this reason, it is preferable to form the opening 20A through photolithography using a photosensitive resin material or a silicon plate as the material of the cover plate 20. In this way, the cover plate 20 changes the pitch of the flow path by the opening 20A. Here, in consideration of the pressure loss, it is preferable to form the cover plate 20 with a thin film-shaped member.

37 is a perspective view showing a cross section of the recording element substrate 310 and the cover plate 20 taken along the line XXXVII-XXXVII in FIG. 36A. Here, the flow of the liquid in the recording element substrate 310 will be described. The cover plate 20 serves as a cover forming a part of a wall of the liquid supply path 318 and the liquid recovery path 319 formed in the substrate 311 of the recording element substrate 310. The recording element substrate 310 is formed by laminating a substrate 311 made of Si and a discharge port forming member 312 made of a photosensitive resin, and the cover plate 20 is bonded to the back surface of the substrate 311. A recording element 315 is provided on one side of the substrate 311 (see FIG. 36B), and a groove forming a liquid supply path 318 and a liquid recovery path 319 extending along a row of discharge ports is provided on the back side thereof. Is provided. The liquid supply path 318 and the liquid recovery path 319 formed by the substrate 311 and the cover plate 20 are provided with a common supply path 211 and a common recovery path 212 in each of the path members 210. Each is connected, and a differential pressure is generated between the liquid supply path 318 and the liquid recovery path 319. When recording an image by discharging the liquid from the discharge port 313, the liquid in the liquid supply path 318 provided in the substrate 311 at the discharge port that does not discharge the liquid is supplied to the supply port 317a and the pressure chamber ( 323), and flows toward the liquid recovery path 319 through the recovery port 317b (see arrow C in FIG. 37). By this flow, in the discharge port 313 or the pressure chamber 323 not accompanied by a discharge operation, thickened ink, air bubbles, and foreign matter generated by evaporation from the discharge port 313 are collected in the liquid recovery path 319 can do. Further, it is possible to suppress the thickening of ink in the discharge port 313 or the pressure chamber 323. The liquid recovered in the liquid recovery path 319 communicates in the flow path member 210 through the opening 20A of the cover plate 20 and the liquid communication port 31 (see FIG. 35B) of the support member 330 The spheres 351, individual recovery flow paths 214, and common recovery flow paths 212 are recovered in this order. After that, the liquid is recovered in the recovery path of the recording apparatus 1000. That is, the liquid supplied from the recording apparatus main body to the liquid discharge head 3 flows in the following order to be supplied and recovered.

The liquid first flows into the liquid discharge head 3 from the liquid connection part 111 of the liquid supply unit 220. In addition, the liquid includes the joint rubber 100, the communication port 72 and the common channel groove 371 provided in the third channel member, the common channel groove 362 and the communication port 361 provided at the second channel member, and It is supplied sequentially through individual flow path grooves 353 and communication ports 351 provided in one flow path member. After that, the liquid is supplied to the liquid communication port 31 provided in the support member 330, the opening 20A provided in the cover plate 20, and the liquid supply path 318 and the supply port 317a provided in the substrate 311 It is supplied to the pressure chamber 23 while passing through sequentially. Among the liquids supplied to the pressure chamber 23, the liquid not discharged from the discharge port 313 is the recovery port 317b provided on the substrate 311, the liquid recovery path 319, and the opening provided in the cover plate 20 ( 20A), and sequentially flow through the liquid communication port 31 provided in the support member 330. Thereafter, the liquid is supplied with a communication port 351 and an individual channel groove 352 provided in the first channel member, a communication port 361 provided in the second channel member, and a common channel groove 362, and the third channel member 370 ) Sequentially flows through the holes of the common flow path groove 371 and the communication port 72, and the joint rubber 100 provided in ). Then, the liquid flows out of the liquid discharge head 3 from the liquid connection part 111 provided to the liquid supply unit 220.

In the first circulation type shown in FIG. 27, the liquid flowing in from the liquid connection part 111 is supplied to the hole of the joint rubber 100 through the negative pressure control unit 230. Further, in the second circulation mode shown in FIG. 28, the liquid recovered from the pressure chamber 323 passes through the hole of the joint rubber 100 and passes through the negative pressure control unit 230 from the liquid connection part 111. It flows out of the liquid discharge head. Not all liquids flowing from one end of the common supply flow path 211 of the liquid discharge unit 300 are supplied to the pressure chamber 323 through the individual supply flow path 213a. That is, the liquid flowing in from one end of the common supply flow path 211 may flow to the liquid supply unit 220 from the other end of the common supply flow path 211 without flowing into the individual supply flow path 213a. In this way, since the path is provided so that the liquid flows without passing through the recording element substrate 310, even in the recording element substrate 310 having a small flow path having a large flow resistance as in this application example, the circulation flow of the liquid It can suppress backflow. In this way, in the liquid discharge head 3 of the present application example, the thickening of the liquid in the vicinity of the discharge port and the pressure chamber 23 can be suppressed, so that retardation or non-discharge of the liquid can be suppressed. As a result, it is possible to record high-quality images.

(Explanation of the positional relationship between the recording element substrates)

Fig. 38 is a partially enlarged plan view showing the adjacent portions of the recording element substrates in two adjacent ejection modules. In this application example, a substantially parallelogram-shaped recording element substrate is used. The discharge port rows 14a to 14d having the discharge ports 313 disposed on each of the recording element substrates 310 are disposed to be inclined at a predetermined angle with respect to the longitudinal direction of the liquid discharge head 3. Further, the rows of discharge ports in adjacent portions between the recording element substrates 310 are formed so that one or more discharge ports overlap in the recording medium transport direction. In Fig. 38, two discharge ports on the line D overlap each other. With this arrangement, even when the position of the recording element substrate 310 is slightly shifted from the predetermined position, black streaks or omissions in the recorded image can be made almost inconspicuous by driving control of the overlapping discharge ports. Even when the recording element substrate 310 is arranged in a linear shape (in-line shape) instead of a zigzag shape, the configuration shown in FIG. 38 suppresses the increase in the length of the liquid discharge head 3 in the recording medium conveyance direction, while recording Black stripes or omissions of the connection portions between the device substrates 10 may be processed. Further, in this application example, the main plane of the recording element substrate has a parallelogram, but the present invention is not limited thereto. For example, even when using a recording element substrate having a rectangular, trapezoidal, or other shape, the configuration of the present invention can be preferably used.

(Description of a modified example of the configuration of the liquid discharge head)

A modified example of the configuration of the liquid discharge head shown in Figs. 47 and 49 to 51 will be described. The description of the same configuration and function as those of the above-described example will be omitted, and only differences will be mainly described.

In this modification, as shown in Figs. 47, 49A, and 49B, the connection part 111 of the liquid between the liquid discharge head 3 and the outside is intensively arranged on one end side in the longitudinal direction of the liquid discharge head. do. A negative pressure control unit 230 is intensively disposed on the other end side of the liquid discharge head 3 (Fig. 50). The liquid supply unit 220 included in the liquid discharge head 3 is configured as an elongated unit corresponding to the length of the liquid discharge head 3, and flow paths and filters 221 corresponding to the four colored liquids respectively supplied. ). As shown in Fig. 50, the positions of the openings 83 to 86 provided in the liquid discharge unit support 81 are also located at different positions from those of the liquid discharge head 3.

51 shows a stacked state of the flow path members 50, 60, and 70. As shown in FIG. The recording element substrate 10 is arranged in a straight line on the upper surface of the channel member 50, which is the uppermost layer of the channel members 50, 60, and 70. As a flow path communicating with the opening 20A (Fig. 36C) of the lid member 20 located on the back side of each recording element substrate 10, two separate supply flow paths 213 and one individual A recovery flow path 214 is provided. Accordingly, as openings 21 formed in the lid member 20 provided on the back surface of the recording element substrate 10, two supply openings 20A and one recovery opening 20A are provided for each color liquid. . As shown in FIG. 51, a common supply flow path 211 and a common recovery flow path 212 extending along the longitudinal direction of the liquid discharge head 3 are alternately arranged.

(2nd application example)

Hereinafter, configurations of the inkjet recording apparatus 2000 and the liquid discharge head 2003 according to the second application example of the present invention will be described with reference to the drawings. In the following description, only differences from the first application example will be described, and the description of the same components as those of the first application example will be omitted.

(Description of inkjet recording device)

46 is a diagram showing an inkjet recording apparatus 2000 according to an application example used for discharging a liquid. The recording apparatus 2000 of this application example has a configuration in which four monochromatic liquid discharge heads 2003 respectively corresponding to cyan (C), magenta (M), yellow (Y), and black (K) inks are arranged in parallel. It differs from the first application example of recording a full-color image on a recording medium. In the first application example, the number of outlet rows that can be used per color is 1. However, in this application example, the number of outlet rows that can be used per color is 20. For this reason, when recording an image by appropriately allocating the recording data to a plurality of discharge port rows, an image can be recorded at higher speed. Further, even when there is a discharge port that does not discharge the liquid, the liquid is complementarily discharged from the discharge openings of different arrangements located at a position corresponding to the non-discharging opening in the recording medium conveyance direction. Reliability is improved and therefore commercial images can be properly recorded. As in the first application example, the supply system of the recording apparatus 2000, the buffer tank 1003 (see Figs. 27 and 28) and the main tank 1006 (see Figs. 27 and 28) are the liquid discharge head 2003. Is in fluid connection. Further, to the liquid discharge head 2003, an electric control unit that transmits electric power and discharge control signals to the liquid discharge head 2003 is electrically connected.

(Explanation of circulation path)

As in the first application example, as the liquid circulation configuration between the recording apparatus 2000 and the liquid discharge head 2003, the first and second circulation types shown in Fig. 27 or 28 can be used.

(Description of the structure of the liquid discharge head)

39A and 39B are perspective views showing a liquid discharge head 2003 according to this application example. Here, the structure of the liquid discharge head 2003 according to this application example will be described. The liquid discharge head 2003 is provided with 16 recording element substrates 2010 arranged linearly in the longitudinal direction of the liquid discharge head 2003, and an inkjet line type recording capable of recording an image with one type of liquid. Head. The liquid discharge head 2003 is provided with a liquid connection part 111, a signal input terminal 91, and a power supply terminal 92, similarly to the first application example. However, since the liquid discharge head 2003 of this application example contains a lot of discharge port rows compared to the first application example, the signal input terminal 91 and the power supply terminal 92 are located on both sides of the liquid discharge head 2003. Is placed. This is because there is a need to reduce a voltage drop or a delay in signal transmission occurring in a wiring portion provided on the recording element substrate 2010.

40 is a perspective exploded view showing the liquid discharge head 2003 and parts or units constituting the liquid discharge head 2003 according to its function. The function or liquid flow sequence of each of the units and members in the liquid discharge head is basically the same as that of the first application example, but the function of ensuring the rigidity of the liquid discharge head is different. In the first application example, the rigidity of the liquid discharge head is mainly secured by the liquid discharge unit support part 381, but in the liquid discharge head 2003 of the second application example, the second flow path included in the liquid discharge unit 2300 The rigidity of the liquid discharge head 2003 is secured by the member 2060. The liquid discharge unit support portion 381 of this application example is connected to both ends of the second flow path member 2060, and the liquid discharge unit 2300 is mechanically connected to the carriage of the recording apparatus 2000 to provide a liquid discharge head ( 2003). The liquid supply unit 2220 including the negative pressure control unit 2230 and the electric wiring board 90 are connected to the liquid discharge unit support 381. Each of the two liquid supply units 2220 includes a filter (not shown) built into it.

The two negative pressure control units 2230 are set to control the pressure differently (relatively high and low negative pressure). In addition, as shown in FIGS. 39A, 39B, and 40, in the case of providing the high-pressure side and low-pressure side negative pressure control units 2230 at both ends of the liquid discharge head 2003, the length direction of the liquid discharge head 2003 The flow of the liquid in the common supply flow path and the common recovery flow path extending to each other face each other. In this configuration, heat exchange between the common supply flow path and the common recovery flow path is promoted, and thus the temperature difference in the two common flow paths is reduced. Accordingly, the temperature difference of the recording element substrate 2010 provided along the common flow path is reduced. As a result, there is an advantage that it becomes difficult to cause uneven recording due to temperature difference.

Next, a detailed configuration of the flow path member 2210 of the liquid discharge unit 2300 will be described. As shown in FIG. 40, the flow path member 2210 is obtained by stacking the first flow path member 2050 and the second flow path member 2060, and discharges the liquid supplied from the liquid supply unit 2220 to the discharge module 2200. To distribute. The flow path member 2210 serves as a flow path member for returning the liquid circulated from the discharge module 2200 to the liquid supply unit 2220. The second flow path member 2060 of the flow path member 2210 has a common supply flow path and a common recovery flow path formed therein, and is a flow path member that improves the rigidity of the liquid discharge head 2003. For this reason, it is preferable that the material of the second flow path member 2060 has sufficient corrosion resistance to liquid and high mechanical strength. Specifically, SUS, Ti, and alumina can be used.

Part (a) of FIG. 41 is a view showing the surface of the first flow path member 2050 on which the discharge module 2200 is mounted, and part (b) of FIG. 41 shows the rear surface and the second flow path member ( 2060) is a view showing a contact surface. Unlike the first application example, the first flow path member 2050 of this application example has a configuration in which a plurality of members corresponding to the discharge module 2200 are disposed adjacent to each other. By employing such a divided structure, a plurality of modules can be arranged to correspond to the length of the liquid discharge head 2003. Thus, such a structure can be suitably used, for example, particularly in a relatively long liquid discharge head corresponding to a sheet having a size of B2 or more. As shown in part (a) of FIG. 41, the communication port 351 of the first flow path member 2050 is in fluid communication with the discharge module 2200. As shown in (b) of FIG. 41, the individual communication ports 353 of the first flow path member 2050 are in fluid communication with the communication ports 361 of the second flow path member 2060. Part (c) of FIG. 41 shows a contact surface of the second flow path member 60 with respect to the first flow path member 2050, and part (d) of FIG. 41 is a central part of the second flow path member 60 in the thickness direction. Fig. 41(e) is a diagram showing a contact surface of the second flow path member 2060 with respect to the liquid supply unit 2220. The functions of the flow path and the communication port of the second flow path member 2060 are the same as those for each color of the first application example. The common flow path groove 371 of the second flow path member 2060 is formed so that one of them is the common supply flow path 2211 shown in FIG. 42 and the other is the common recovery flow path 2212. These flow paths 2211 and 2212 are respectively provided along the longitudinal direction of the liquid discharge head 2003, and liquid is supplied from one end thereof to the other end thereof. This form is different from the first application example in that the liquid flow directions of the common supply flow path 2211 and the common recovery flow path 2212 are opposite to each other.

42 is a perspective view showing a liquid connection relationship between the recording element substrate 2010 and the flow path member 2210. In the passage member 2210, a pair of common supply passages 2211 and a common recovery passage 2212 extending in the longitudinal direction of the liquid discharge head 2003 are provided. The communication ports 361 of the second flow path member 2060 are connected to the individual communication ports 353 of the first flow path member 2050 so that both positions coincide with each other. Accordingly, a liquid supply flow path that communicates with the communication port 351 of the first flow path member 2050 through the communication port 361 from the common supply flow path 2211 of the second flow path member 2060 is formed. Similarly, a liquid supply path that communicates with the communication port 351 of the first flow path member 2050 through the common recovery flow path 2212 from the communication port 72 of the second flow path member 2060 is also formed.

43 is a cross-sectional view taken along the line XLIII-XLIII in FIG. 42; The common supply channel 2211 is connected to the discharge module 2200 through a communication port 361, an individual communication port 353, and a communication port 351. Although not shown in FIG. 43, it is clear that the common recovery flow path 2212 is connected to the discharge module 2200 by the same path in a different cross section of FIG. 42. As in the first application example, each discharge module 2200 and the recording element substrate 2010 are provided with flow paths in communication with each discharge port, so that some or all of the supplied liquid passes through the discharge ports that do not perform the discharge operation. It can be cycled while doing. In addition, as in the first application example, the common supply flow path 2211 is connected to the negative pressure control unit 2230 (high pressure side), and the common recovery flow path 2212 is a liquid supply unit to the negative pressure control unit 2230 (low pressure side). It is connected via 2220. Accordingly, a flow is formed so that the liquid flows from the common supply flow path 2211 to the common recovery flow path 2212 through the pressure chamber of the recording element substrate 2010 by the differential pressure.

(Description of the discharge module)

44A is a perspective view showing one discharge module 2200, and FIG. 44B is an exploded view thereof. The difference from the first application example is that the terminals 316 are respectively disposed on both sides of the recording element substrate 2010 in the discharge port column direction (long edges of the recording element substrate 2010). Accordingly, two flexible circuit boards 40 electrically connected to the recording element substrate 2010 are disposed for each recording element substrate 2010. Since the number of discharge port rows provided to the recording element substrate 2010 is 20, the discharge port rows are larger than the eight discharge port rows in the first application example. Here, since the maximum distance from the terminal 316 to the recording element is shortened, a voltage drop or signal delay occurring at the wiring portion in the recording element substrate 2010 is reduced. Further, the liquid communication ports 31 of the support member 2030 are opened along the entire row of discharge ports provided on the recording element substrate 2010. Other configurations are the same as those of the first application example.

(Description of the structure of the recording element substrate)

FIG. 45A is a schematic diagram showing the surface of the recording element substrate 2010 on which the discharge port 313 is disposed, and FIG. 45C is a schematic diagram showing the rear surface of the surface of FIG. 45A. 45B is a schematic diagram showing the surface of the recording element substrate 2010 when the cover plate 2020 provided on the back surface of the recording element substrate 2010 in FIG. 45C is removed. As shown in Fig. 45B, a liquid supply path 318 and a liquid recovery path 319 are alternately provided on the rear surface of the recording element substrate 2010 along the discharge port row direction. The number of outlet rows is larger than that of the first application example. However, the basic difference from the first application example is that, as described above, the terminals 316 are disposed on both sides of the recording element substrate in the discharge port column direction. In the basic configuration, a pair of liquid supply paths 318 and liquid recovery paths 319 are provided for each discharge port row, and the cover plate 2020 communicates with the liquid communication port 31 of the support member 2030. It is the same as in the first application example in that the opening 20A is provided.

In addition, the description of the application examples described above does not limit the scope of the present invention. As an example, in the application example, a thermal type in which air bubbles are generated by a heating element to discharge a liquid has been described. However, the present invention can also be applied to a liquid discharge head employing a piezoelectric type and various other liquid discharge types.

In the application example, an inkjet recording apparatus (recording apparatus) in which a liquid such as ink circulates between a tank and a liquid discharge head has been described, but other application examples may also be used. In another application, for example, a configuration in which two tanks are provided on the upstream side and the downstream side of the liquid discharge head so that ink is not circulated and ink flows from one tank to another may be employed. In this way, the ink in the pressure chamber can flow.

In the application example, an example of using a so-called line type head having a length corresponding to the width of the recording medium has been described, but the present invention is also applied to a so-called serial type liquid discharge head that records an image on the recording medium while scanning the recording medium. I can. As a serial type liquid discharge head, for example, a recording element substrate for discharging black ink and a recording element substrate for discharging color ink may be mounted on the liquid discharge head, but the present invention is not limited thereto. That is, a liquid discharge head including a plurality of recording element substrates that is shorter than the width of the recording medium and arranged so that the discharge ports overlap each other in the discharge port column direction can be provided, and the liquid discharge head can be scanned for the recording medium. .

(3rd application example)

The configurations of the inkjet recording apparatus 1000 and the liquid discharge head 3 according to the third application example of the present invention will be described. The liquid discharge head of the third application example is of a page-wide type in which an image is recorded on a B2-size recording medium through one scan. Since the third application example is the same in many aspects as the second application example, only the difference from the second application example will be mainly described in the following description, and the description of the same configuration as that of the second application example will be omitted.

(Description of inkjet recording device)

52 is a schematic diagram showing an inkjet recording apparatus according to this application example. The recording apparatus 1000 has a configuration in which an image is not directly recorded on a recording medium by the liquid discharged from the liquid discharge head 3. That is, the liquid is first discharged to the intermediate transfer member (intermediate transfer drum) 1007 to form an image thereon, and the image is transferred to the recording medium 2. In the recording apparatus 1000, liquid discharge heads 3 respectively corresponding to the ink of four colors (C, M, Y, K) are arranged along the intermediate transfer drum 1007 in an arc shape. Therefore, full-color recording is performed on the intermediate transfer member, the recorded image is appropriately dried on the intermediate transfer member, and the image is transferred to the recording medium 2 conveyed to the transfer unit 1008 by the sheet conveying roller 1009. do. The sheet conveying system of the second application example is mainly used to convey cut sheets in the horizontal direction. However, the sheet conveying system of this application example can also be applied to a continuous sheet supplied from a main roll (not shown). In such a drum conveying system, since the sheet is easily conveyed while imparting a predetermined tension to the sheet, a conveying jam hardly occurs even in a high-speed recording operation. Because of this, the reliability of the device is improved, and thus the device is suitable for commercial printing purposes. Similar to the first and second application examples, the supply systems of the recording apparatus 1000, the buffer tank 1003, and the main tank 1006 are fluidly connected to each of the liquid discharge heads 3. Further, to each of the liquid discharge heads 3, an electric control unit that transmits electric power and a discharge control signal to the liquid discharge head 3 is electrically connected.

(Explanation of the fourth circulation form)

Like the second application example, the first and second circulation paths shown in FIG. 27 or 28 may be applied as a liquid circulation path between the liquid discharge head 3 and the tank of the recording apparatus 1000, but in FIG. The illustrated circulation path is preferred. The main difference from the second circulation path of FIG. 28 is that a bypass valve 1010 is additionally provided to communicate with each of the flow paths of the first circulation pumps 1001 and 1002 and the second circulation pump 1004. The bypass valve 1010 has a function (first function) of lowering the upstream pressure of the bypass valve 1010 by opening the valve when the pressure exceeds a preset pressure. Further, the bypass valve 1010 has a function (second function) of opening and closing the valve at an arbitrary timing in response to a signal from the control board of the recording apparatus main body.

By the first function, it is possible to suppress that a large or small pressure is applied to the downstream side of the first circulation pumps 1001 and 1002 or upstream of the second circulation pump 1004. For example, when the functions of the first circulation pumps 1001 and 1002 do not operate properly, there is a case where a large flow rate or pressure may be applied to the liquid discharge head 3. Therefore, there is a fear that the liquid may leak from the discharge port of the liquid discharge head 3 or the respective joints in the liquid discharge head 3 may be destroyed. However, when the bypass valve 1010 is added to the first circulation pumps 1001 and 1002 as in the present application example, the bypass valve 1010 is opened when a large pressure is generated. Therefore, since the liquid path is opened on the upstream side of each circulation pump, the above-described problem can be suppressed.

In addition, when the circulation drive operation is stopped by the second function, after the operation of the first circulation pumps 1001 and 1002 and the second circulation pump 1004 is stopped, all The bypass valve 1010 opens quickly. Accordingly, a high negative pressure (for example, several to tens of kPa) of the downstream portion of the liquid discharge head 3 (between the negative pressure control unit 230 and the second circulation pump 1004) can be released in a short time. When a positive displacement pump such as a diaphragm pump is used as the circulation pump, a check valve is usually incorporated in the pump. However, when the bypass valve 1010 is opened, the pressure at the downstream portion of the liquid discharge head 3 can also be released from the downstream portion of the buffer tank 1003. Although the pressure in the downstream portion of the liquid discharge head 3 can be released only from the upstream side, pressure loss exists in the upstream flow path of the liquid discharge head and the flow path in the liquid discharge head. Therefore, it takes some time to release the pressure, so that the pressure in the common flow path in the liquid discharge head 3 is temporarily excessively lowered. Therefore, there is a fear that the meniscus of the discharge port is destroyed. However, since the release of the pressure on the downstream side of the liquid discharge head is promoted when the bypass valve 1010 on the downstream side of the liquid discharge head 3 is opened, the risk of destruction of the meniscus of the discharge port is reduced.

(Description of the structure of the liquid discharge head)

The structure of the liquid discharge head 3 according to the third application example of the present invention will be described. Fig. 54A is a perspective view showing the liquid discharge head 3 according to this application example, and Fig. 54B is an exploded perspective view thereof. The liquid discharge head 3 is provided with 36 recording element substrates 10 arranged in a linear shape (in-line shape) in the longitudinal direction of the liquid discharge head 3, and an inkjet page wide type recording for recording images in one color. Head. As in the second application example, the liquid discharge head 3 includes a shield plate 132 that protects the rectangular side of the head in addition to the signal input terminal 91 and the power supply terminal 92.

54B is an exploded perspective view showing the liquid discharge head 3. In Fig. 54B, parts or units constituting the liquid discharge head 3 are divided and shown according to their functions (shield plate 132 is not shown). The functions of the units and members and the order of liquid circulation in the liquid discharge head 3 are the same as those of the second application example. The main difference from the second application example is that the divided electric wiring board 90 and the negative pressure control unit 230 are disposed at different positions and the first flow path members have different shapes. As in this application example, in the case of the liquid discharge head 3 having a length corresponding to, for example, a B2 size recording medium, since the power consumed by the liquid discharge head 3 is large, eight electric wiring boards ( 90) is provided. Four electric wiring boards 90 are attached to each of both sides of the elongate electric wiring board support portion 82 attached to the liquid discharge unit support portion 81.

54A is a side view showing a liquid discharge head 3 having a liquid discharge unit 300, a liquid supply unit 220 and a negative pressure control unit 230, and FIG. 54B is a schematic view showing a flow of a liquid, 54C is a perspective view illustrating a cross-sectional view taken along the line LVC-LVC in FIG. 54A. In order to facilitate understanding of the drawings, some configurations have been simplified.

A liquid connection part 111 and a filter 221 are provided in the liquid supply unit 220, and the negative pressure control unit 230 is formed integrally with the lower side of the liquid supply unit 220. Therefore, the distance in the height direction between the negative pressure control unit 230 and the recording element substrate 10 is shortened compared to the second application example. With this configuration, the number of flow path connections in the liquid supply unit 220 is reduced. As a result, there is an advantage that the reliability of preventing leakage of the recording liquid is improved and the number of parts or assembly steps is reduced.

In addition, since the water head difference between the negative pressure control unit 230 and the discharge port formation surface of the liquid discharge head 3 is relatively small, this configuration has an inclination angle of the liquid discharge head 3 shown in FIG. It can be suitably applied to different recording apparatuses for each head. Since the water head difference can be made small, even if the liquid discharge head 3 having different inclination angles is used, the negative pressure difference applied to the discharge port of the recording element substrate can be reduced. Further, since the distance from the negative pressure control unit 230 to the recording element substrate 10 becomes small, the flow resistance therebetween decreases. Therefore, the difference in pressure loss caused by the change in the flow rate of the liquid becomes small, so that the negative pressure can be more preferably controlled.

55B is a schematic diagram showing the flow of the recording liquid inside the liquid discharge head 3. The circulation path is similar to the circulation path shown in FIG. 53 in terms of its circuit, but FIG. 55B shows the flow of liquid in each component of the actual liquid discharge head 3. In the elongate second flow path member 60, a pair of common supply flow paths 211 and common recovery flow paths 212 extending in the longitudinal direction of the liquid discharge head 3 are provided. The common supply flow path 211 and the common recovery flow path 212 are configured so that liquid flows in opposite directions therein, and a filter 221 is provided on the upstream side of each flow path to penetrate from the connection part 111, etc. Trap foreign substances. In this way, since the liquid flows in opposite directions through the common supply flow passage 211 and the common recovery flow passage 212, the temperature gradient in the longitudinal direction in the liquid discharge head 3 can be preferably reduced. In order to simplify the description of FIG. 53, the flows in the common supply flow path 211 and the common recovery flow path 212 are shown in the same direction.

A negative pressure control unit 230 is connected to the downstream side of each of the common supply flow path 211 and the common recovery flow path 212. In addition, a branch portion is provided in the middle of the common supply passage 211 so as to be connected to the individual supply passage 213a, and a branch portion is provided in the middle of the common recovery passage 212 so as to be connected to the individual recovery passage 213b. The individual supply flow path 213a and the individual recovery flow path 213b are formed in the first flow path member 50, and each individual flow path is an opening 10A of the cover member 20 provided on the back surface of the recording element substrate 10. ) (See Fig. 36c).

The negative pressure control units 230 indicated by "H" and "L" in Fig. 55B are units on the high pressure side (H) and the low pressure side (L). The negative pressure control unit 230 is a back pressure type pressure adjusting mechanism that controls the upstream pressure of the negative pressure control unit 230 by a relatively high negative pressure H and a relatively low negative pressure L. The common supply flow path 211 is connected to the negative pressure control unit 230 (high pressure side), and the common recovery flow path 212 is connected to the negative pressure control unit 230 (low pressure side), and thus the common supply flow path 211 and A differential pressure is generated between the common recovery flow paths 212. Due to the differential pressure, the liquid sequentially flows from the common supply flow path 211 to the individual supply flow path 213a, the discharge port 11 (pressure chamber 23) in the recording element substrate 10, and the individual recovery flow path 213b. It flows through the common recovery flow path 212 while passing.

55C is a perspective view illustrating a cross-sectional view taken along the line LVC-LVC in FIG. 55A. In this application example, each discharge module 200 includes a first flow path member 50, a recording element substrate 10, and a flexible circuit board 40. In this application example, the support member 2030 (FIG. 43) described in the second application example does not exist, and the recording element substrate 10 including the cover member 20 is directly bonded to the first flow path member 50 do. The liquid is individually supplied from the communication port 61 formed on the upper surface of the common supply channel 211 provided to the second channel member 60 through the individual communication port 53 formed on the lower surface of the first flow channel member 50. It is supplied to the supply flow path 213a. After that, the liquid passes through the pressure chamber 23, passes through the individual recovery flow path 213b, the individual communication port 53, and the communication port 61, and is recovered in the common recovery flow path 212.

Here, unlike the second application example shown in FIG. 40, the individual communication ports 53 formed on the lower surface of the first flow path member 50 (the surface near the second flow path member 60) are the second flow paths. It is large enough for the communication port 61 formed on the upper surface of the member 50. With this configuration, even when a positional shift occurs when the discharge module 200 is mounted on the second flow path member 60, the first flow path member and the second flow path member reliably communicate with each other in fluid communication. As a result, the yield in the head manufacturing process is improved and cost reduction can be realized.

(Another Example)

The present invention is not limited to only the ink ejection substrate, the inkjet recording head, and the inkjet recording apparatus, but can be widely applied to a liquid ejection substrate, a liquid ejection head, and a liquid ejection apparatus used to eject various liquids. The present invention can also be applied to various types of recording apparatuses such as a full line method and a serial scan method.

Further, the present invention is widely applicable to a liquid ejection apparatus using a liquid ejection head capable of ejecting various liquids, in addition to an inkjet recording apparatus which records an image using an ink jet recording head capable of ejecting ink. For example, the present invention is applicable to a printer, a copier, a facsimile having a communication system, a word processor having a printer, and an industrial recording apparatus combined with various processing devices. In addition, the present invention can be used for biochip fabrication or electronic circuit printing.

According to the present invention, a plurality of supply passages, a plurality of collection passages, a first common supply passage, and a first common recovery passage may be formed with high precision. Thus, even when the plurality of discharge ports are densely arranged, the liquid can be circulated through the pressure chambers respectively corresponding to the discharge ports. As a result, satisfactory discharge performance of discharging the liquid from the discharge port can be maintained. For example, when ink is discharged from a discharge port to record an image, it is possible to record a high-quality image with high accuracy by suppressing a decrease in the ink discharge rate due to evaporation of water in the ink from the discharge port.

While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the following claims is to be accorded the widest interpretation so as to cover all such modifications and equivalent structures and functions.

Claims (15)

A liquid discharge substrate having a discharge port for discharging a liquid, a discharge energy generating element for generating energy used to discharge the liquid, and a pressure chamber having the discharge energy generating element therein,
The liquid discharge substrate includes a first part and a second part disposed below the first part in a thickness direction of the liquid discharge substrate,
In the first portion, a plurality of discharge ports arranged in a first direction and a plurality of pressure chambers arranged correspondingly, a first flow path communicating with one of the arranged pressure chambers, and the other side of the arranged pressure chambers A second flow path, a plurality of supply flow paths communicating with the first flow path to supply liquid to the pressure chamber, and a plurality of recovery flow paths communicating with the second flow path to recover liquid from the pressure chamber are provided, the When the substrate for liquid discharge is viewed from the discharge port side, the supply flow path and the recovery flow path are disposed to face each other with the discharge port interposed therebetween,
In the second portion, a common supply flow path communicating with the first flow path through the plurality of supply flow paths, and a common recovery flow path communicating with the second flow path through the plurality of recovery flow paths are provided,
The common supply flow path and the common recovery flow path extend in the first direction,
Each of the supply flow paths and each of the recovery flow paths extend in a direction crossing a surface on which the discharge energy generating element is provided,
Flow resistance per unit length from the downstream end of the supply flow path to the upstream end of the recovery flow path through the pressure chamber is represented by R, and flows through the pressure chamber in a state in which no liquid is discharged from the discharge port. When the flow rate of the liquid is represented by Q1 and the maximum negative pressure at which the liquid can be discharged from the discharge port is represented by P, the beam width (W) between the common supply channel and the common recovery channel is W<(2×P) A substrate for liquid discharge that satisfies the relationship of )/(Q1×R). A liquid discharge substrate having a discharge port for discharging a liquid, a discharge energy generating element for generating energy used to discharge the liquid, and a pressure chamber having the discharge energy generating element therein,
The liquid discharge substrate includes a first part and a second part disposed below the first part in a thickness direction of the liquid discharge substrate,
In the first portion, a plurality of discharge ports arranged in a first direction and a plurality of pressure chambers arranged correspondingly, a first flow path communicating with one of the arranged pressure chambers, and the other side of the arranged pressure chambers A second flow path, a plurality of supply flow paths communicating with the first flow path to supply liquid to the pressure chamber, and a plurality of recovery flow paths communicating with the second flow path to recover liquid from the pressure chamber are provided, the When the substrate for liquid discharge is viewed from the discharge port side, the supply flow path and the recovery flow path are disposed to face each other with the discharge port interposed therebetween,
In the second portion, a common supply flow path communicating with the first flow path through the plurality of supply flow paths, and a common recovery flow path communicating with the second flow path through the plurality of recovery flow paths are provided,
The common supply flow path and the common recovery flow path extend in the first direction,
Each of the supply flow paths and each of the recovery flow paths extend in a direction crossing a surface on which the discharge energy generating element is provided,
The flow path resistance per unit length from the downstream end of the supply flow path to the upstream end of the recovery flow path through the pressure chamber is represented by R, and the maximum discharge amount of the liquid discharged from the discharge port is represented by Q2, and the discharge port When the maximum negative pressure at which the liquid can be discharged from is represented by P, the beam width (W) between the common supply flow path and the common recovery flow path satisfies the relationship W<(2×P)/(Q2×R). A substrate for liquid discharge. A liquid discharge substrate having a discharge port for discharging a liquid, a discharge energy generating element for generating energy used to discharge the liquid, and a pressure chamber having the discharge energy generating element therein,
The liquid discharge substrate includes a first part and a second part disposed below the first part in a thickness direction of the liquid discharge substrate,
In the first portion, a plurality of discharge ports arranged in a first direction and a plurality of pressure chambers arranged correspondingly, a first flow path communicating with one of the arranged pressure chambers, and the other side of the arranged pressure chambers A second flow path, a plurality of supply flow paths communicating with the first flow path to supply liquid to the pressure chamber, and a plurality of recovery flow paths communicating with the second flow path to recover liquid from the pressure chamber are provided, the When the substrate for liquid discharge is viewed from the discharge port side, the supply flow path and the recovery flow path are disposed to face each other with the discharge port interposed therebetween,
In the second portion, a common supply flow path communicating with the first flow path through the plurality of supply flow paths, and a common recovery flow path communicating with the second flow path through the plurality of recovery flow paths are provided,
The common supply flow path and the common recovery flow path extend in the first direction,
Each of the supply flow paths and each of the recovery flow paths extend in a direction crossing a surface on which the discharge energy generating element is provided,
Flow resistance per unit length from the downstream end of the supply flow path to the upstream end of the recovery flow path through the pressure chamber is represented by R, and flows through the pressure chamber in a state in which no liquid is discharged from the discharge port. When the flow rate of the liquid is expressed as Q1 and the maximum negative pressure at which the liquid can be discharged from the discharge port is expressed as P, the distance W between the downstream end of the common supply flow path and the upstream end of the common recovery flow path A substrate for liquid discharge that satisfies the relationship of W<(2×P)/(Q1×R). A liquid discharge substrate having a discharge port for discharging a liquid, a discharge energy generating element for generating energy used to discharge the liquid, and a pressure chamber having the discharge energy generating element therein,
The liquid discharge substrate includes a first part and a second part disposed below the first part in a thickness direction of the liquid discharge substrate,
In the first portion, a plurality of discharge ports arranged in a first direction and a plurality of pressure chambers arranged correspondingly, a first flow path communicating with one of the arranged pressure chambers, and the other side of the arranged pressure chambers A second flow path, a plurality of supply flow paths communicating with the first flow path to supply liquid to the pressure chamber, and a plurality of recovery flow paths communicating with the second flow path to recover liquid from the pressure chamber are provided, the When the substrate for liquid discharge is viewed from the discharge port side, the supply flow path and the recovery flow path are disposed to face each other with the discharge port interposed therebetween,
In the second portion, a common supply flow path communicating with the first flow path through the plurality of supply flow paths, and a common recovery flow path communicating with the second flow path through the plurality of recovery flow paths are provided,
The common supply flow path and the common recovery flow path extend in the first direction,
Each of the supply flow paths and each of the recovery flow paths extend in a direction crossing a surface on which the discharge energy generating element is provided,
The flow path resistance per unit length from the downstream end of the supply flow path to the upstream end of the recovery flow path through the pressure chamber is represented by R, and the maximum discharge amount of the liquid discharged from the discharge port is represented by Q2, and the When the maximum negative pressure at which the liquid can be discharged from the discharge port is represented by P, the distance W between the downstream end of the common supply flow path and the upstream end of the common recovery flow path is W<(2×P)/ A substrate for liquid discharge that satisfies the relationship of (Q2×R). A liquid discharge substrate having a discharge port for discharging a liquid, a discharge energy generating element for generating energy used to discharge the liquid, and a pressure chamber having the discharge energy generating element therein,
The liquid discharge substrate includes a first part and a second part disposed below the first part in a thickness direction of the liquid discharge substrate,
In the first portion, a plurality of discharge ports arranged in a first direction and a plurality of pressure chambers arranged correspondingly, a first flow path communicating with one of the arranged pressure chambers, and the other side of the arranged pressure chambers A second flow path, a plurality of supply flow paths communicating with the first flow path to supply liquid to the pressure chamber, and a plurality of recovery flow paths communicating with the second flow path to recover liquid from the pressure chamber are provided, the When the substrate for liquid discharge is viewed from the discharge port side, the supply flow path and the recovery flow path are disposed to face each other with the discharge port interposed therebetween,
In the second portion, a common supply flow path communicating with the first flow path through the plurality of supply flow paths, and a common recovery flow path communicating with the second flow path through the plurality of recovery flow paths are provided,
The common supply flow path and the common recovery flow path extend in the first direction,
A beam width between the common supply passage and the common recovery passage communicating with a first discharge port row in which a plurality of discharge ports are disposed is represented by W1, and the common supply passage and the first discharge port communicating with the first discharge port row A substrate for liquid discharge, wherein the relationship of W1 < W3 is satisfied when the beam width between the common recovery flow path communicating with the second discharge port row provided in parallel with the row is represented by W3. A liquid discharge substrate having a discharge port for discharging a liquid, a discharge energy generating element for generating energy used to discharge the liquid, and a pressure chamber having the discharge energy generating element therein,
The liquid discharge substrate includes a first part and a second part disposed below the first part in a thickness direction of the liquid discharge substrate,
In the first portion, a plurality of discharge ports arranged in a first direction and a plurality of pressure chambers arranged correspondingly, a first flow path communicating with one of the arranged pressure chambers, and the other side of the arranged pressure chambers A second flow path, a plurality of supply flow paths communicating with the first flow path to supply liquid to the pressure chamber, and a plurality of recovery flow paths communicating with the second flow path to recover liquid from the pressure chamber are provided, the When the substrate for liquid discharge is viewed from the discharge port side, the supply flow path and the recovery flow path are disposed to face each other with the discharge port interposed therebetween,
In the second portion, a common supply flow path communicating with the first flow path through the plurality of supply flow paths, and a common recovery flow path communicating with the second flow path through the plurality of recovery flow paths are provided,
The common supply flow path and the common recovery flow path extend in the first direction,
The liquid discharge substrate discharges a plurality of types of liquids,
The beam width between the common supply passage and the common recovery passage disposed between adjacent rows of discharge ports that discharge the same type of liquid is represented by W3, and the common disposed between adjacent rows of discharge ports that discharge different types of liquid. A liquid discharge substrate in which the relationship W3 < W4 is satisfied when the beam width between the supply flow passage and the common recovery flow passage is represented by W4. The method according to claim 1 or 2,
The width of the supply passage in a second direction orthogonal to the first direction is smaller than the width of the common supply passage in the second direction,
A substrate for liquid discharge, wherein a width of the recovery passage in the second direction is smaller than a width of the common recovery passage in the second direction. The method according to claim 1 or 2,
The common supply flow path and the common recovery flow path extend along each other, and a distance W between the common supply flow path and the common recovery flow path is 200 μm or less. The method according to claim 1 or 2,
A substrate for liquid discharge, wherein a distance between the supply flow path and the recovery flow path is smaller than a distance between the common supply flow path and the common recovery flow path. The method according to claim 1 or 2,
The center of the supply passage in a second direction orthogonal to the first direction is closer to the discharge port than the center of the common supply passage in the second direction,
A substrate for liquid discharge, wherein a center of the recovery flow path in the second direction is closer to the discharge port than a center of the common recovery flow path in the second direction. The method according to claim 1 or 2,
The supply flow path and the recovery flow path extend in a direction crossing a surface of the liquid discharge substrate on which the discharge energy generating element is provided. The method according to claim 1 or 2,
The liquid discharge substrate has a substantially parallelogram shape,
Both ends of a first common supply flow path in which the plurality of discharge ports communicate with a first discharge port row disposed therein in a first direction, and a second common supply flow path in communication with a second discharge port row provided in parallel with the first discharge port row Both ends of the substrate are displaced in the first direction. The method of claim 12,
At least one of the common supply flow passage and the common recovery flow passage in communication with the first discharge port row, at least one end portion in the first direction, is formed in a chamfered shape or a round shape. The method according to claim 1 or 2,
The liquid discharge substrate, wherein the number relationship between the supply flow path and the discharge port is 1 to 1, 1 to 2, or 1 to 5. A liquid discharge head comprising the substrate for liquid discharge according to claim 1 or 2, comprising:
A first liquid connection part for supplying a liquid to the common supply passage;
A liquid discharge head comprising a second liquid connection part for recovering liquid from the common recovery passage.

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