JP7379549B2 - Liquid ejection head and liquid ejection device - Google Patents

Description

The present invention relates to a liquid ejection head and a liquid ejection device that eject liquid from ejection ports.

2. Description of the Related Art In recent years, recording applications for recording apparatuses have become more diverse, and as a result, demands for high-definition and high-quality recording are increasing. In order to achieve higher definition recording, a liquid ejection head capable of selectively ejecting liquid from a plurality of ejection ports is required to have a higher density arrangement of ejection ports. Furthermore, in order to achieve even higher quality recording, it is required to eject droplets of uniform size.

In order to increase the density of the arrangement of the ejection ports, it is also necessary to miniaturize the liquid supply channel for supplying liquid to the ejection ports. Patent Document 1 describes a method in which a sealing film integrated in the longitudinal direction of a line head is used as a member for supplying ink to an element substrate, and after laminating it on a head support member, a supply opening is formed using a laser. is listed. Thereafter, the recording element substrate is mounted on the sealing film in which the supply opening is formed.

US Patent No. 7347534

However, in the method disclosed in Patent Document 1, after forming a supply opening in a sealing film that is a support member for a recording element substrate, the recording element substrate is mounted on the sealing film while being positioned to correspond to the formed supply opening. It is something to do. With such a configuration, it is difficult to further miniaturize or increase the density of the flow channels and supply openings on the back side of the recording element substrate from the viewpoint of positioning accuracy between the flow channels on the back side of the recording element substrate and the supply openings of the sealing film. becomes.

SUMMARY OF THE INVENTION An object of the present invention is to provide a liquid ejection head and a liquid ejection apparatus that can accommodate further miniaturization and higher density of flow path configurations on the back side of a recording element substrate.

Therefore, the liquid ejection head of the present invention includes an ejection port for ejecting liquid, an element that is provided corresponding to the ejection port and that generates energy for ejecting the liquid from the ejection port, and an element that is provided internally to eject the liquid. a plurality of element substrates comprising: a plurality of element substrates comprising: a supply opening provided on the back surface of the element substrate on the side where the discharge port is formed for supplying liquid to the pressure chambers; a lid member provided on each of the element substrates, the liquid ejection head comprising a lid member provided on each of the element substrates, the liquid ejection head having a supply hole on the back surface of the element substrate for supplying the liquid supplied from the supply opening to the pressure chamber. A part of the supply path is formed by the lid member, and when the liquid ejection head is viewed from the side facing the ejection port, the outer shape of the lid member is similar to the element substrate. The lid member further includes a recovery opening for recovering liquid from the pressure chamber, and is located on the back side of the element substrate on the end side in the longitudinal direction of the lid member. Further, a recovery path is provided for recovering the liquid recovered from the pressure chamber of the element substrate into the recovery opening, a part of the recovery path is formed by the lid member, and the lid member is , a liquid ejection head characterized by being made of a resin film .

According to the present invention, it is possible to realize a liquid ejection head and a liquid ejection device that can suppress pressure variations in pressure chambers.

1 is a diagram showing a schematic configuration of a liquid ejection device that ejects liquid. FIG. 3 is a schematic diagram showing a first circulation form of a circulation path applied to the recording apparatus. FIG. 7 is a schematic diagram showing a second circulation form of a circulation path applied to the recording apparatus. FIG. 3 is a schematic diagram showing differences in the amount of ink flowing into the liquid ejection head. FIG. 3 is a perspective view showing a liquid ejection head. FIG. 2 is an exploded perspective view showing each component or unit constituting the liquid ejection head. FIG. 3 is a diagram showing the front and back surfaces of each of the first to third flow path members. FIG. 7A is a perspective view of section α in FIG. 7A, viewed from the surface on which the ejection module is mounted. 9 is a diagram showing a cross section taken along line IX-IX in FIG. 8. FIG. FIG. 2 is a perspective view and an exploded view of one discharge module. FIG. 3 is a diagram showing a recording element substrate. FIG. 2 is a perspective view showing a cross section of a recording element substrate and a lid member. FIG. 3 is a partially enlarged plan view of an adjacent portion of the recording element substrate. FIG. 3 is a perspective view showing a liquid ejection head. FIG. 2 is a perspective exploded view showing a liquid ejection head. It is a figure showing a 1st channel member. FIG. 3 is a perspective view showing a liquid connection relationship between a recording element substrate and a flow path member. 18 is a diagram showing a cross section taken along line XVIII-XVIII in FIG. 17. FIG. FIG. 2 is a perspective view and an exploded view of one discharge module. FIG. 2 is a schematic diagram showing a recording element substrate. 1 is a diagram illustrating an inkjet recording apparatus that performs recording by ejecting liquid. FIG. 3 is a diagram showing a recording element substrate and a lid member. FIG. 3 is a perspective view showing a liquid ejection head. 1 is a diagram showing an outline and flow path configuration of a liquid discharge recording device. It is an exploded perspective view showing a liquid discharge unit. It is an exploded perspective view showing a liquid discharge unit. FIG. 3 is a diagram showing a discharge port superimposed on an enlarged view of a part of the first channel layer. FIG. 3 is a cross-sectional view showing a liquid supply path and a liquid recovery path in the second channel layer. FIG. 3 is a perspective view showing a liquid supply path and a liquid recovery path in the second channel layer. 3 is a flowchart showing an example of a manufacturing process of a liquid ejection head. FIG. 3 is a diagram showing a recording element substrate. 32 is a sectional view taken along XXXII-XXXII in FIG. 31. FIG. 32 is a sectional view taken along XXXII-XXXII in FIG. 31. FIG. FIG. 3 is a diagram showing the arrangement relationship between a liquid supply opening and a liquid supply path. It is a graph showing the relationship between the width of the supply opening, pressure loss, circulation flow rate, and variation. FIG. 3 is a diagram showing the relationship between the external shapes of the element substrate and the lid member. FIG. 3 is a diagram showing the positions of a recording element substrate, a liquid supply opening, and a liquid recovery opening. FIG. 3 is a diagram showing a liquid ejection unit. FIG. 3 is a diagram showing a liquid ejection unit. FIG. 3 is a diagram showing a liquid ejection unit. FIG. 3 is a diagram showing a liquid ejection unit. FIG. 3 is a diagram showing a liquid ejection unit. 7 is a graph showing the temperature distribution of the recording element substrate when ejecting from all the ejection ports. 7 is a graph showing the temperature distribution of the recording element substrate. It is a figure showing the modification regarding the shape of a liquid supply opening. FIG. 3 is a diagram illustrating an example of a configuration of a gap between adjacent recording element substrates. FIG. 3 is a diagram illustrating an example of a configuration of a gap between adjacent recording element substrates. FIG. 3 is a diagram illustrating an example of a configuration of a gap between adjacent substrates. FIG. 3 is a diagram illustrating an example of a configuration of a gap between adjacent substrates. FIG. 3 is an exploded perspective view of the liquid ejection unit. FIG. 3 is an exploded plan view of the liquid ejection unit. FIG. 3 is a diagram showing a liquid ejection unit. FIG. 3 is a diagram showing a liquid ejection unit. FIG. 3 is a diagram showing the arrangement relationship of flow paths of first ink and second ink.

Hereinafter, each application example and each embodiment to which the present invention can be suitably applied will be described with reference to the drawings. The liquid ejection head of the present invention that ejects liquid such as ink and the liquid ejection device equipped with the liquid ejection head can be applied to devices such as printers, copying machines, facsimile machines having communication systems, and word processors having printer sections. Furthermore, it can be applied to industrial recording devices that are combined with various processing devices. For example, it can be used for applications such as biochip production, electronic circuit printing, and semiconductor substrate production.

Moreover, since each application example and each embodiment described below are appropriate specific examples of the present invention, various technically preferable limitations are attached thereto. However, as long as the idea of the present invention is followed, the application examples and embodiments are not limited to the application examples, embodiments, and other specific methods in this specification.

(First application example)
(Description of liquid ejection recording device)
FIG. 1 is a diagram showing a schematic configuration of a liquid ejection apparatus that ejects liquid according to the present invention, particularly a liquid ejection recording apparatus (hereinafter also referred to as a printing apparatus) 1000 that performs recording by ejecting ink. The recording apparatus 1000 includes a conveyance unit 1 that conveys a recording medium 2, and a line-type (page wide type) liquid ejection head 3 that is arranged substantially perpendicular to the conveyance direction of the recording medium 2, and includes a conveyance unit 1 that conveys a recording medium 2. This is a line-type recording device that performs continuous recording in one pass while conveying 2 continuously or intermittently. The liquid ejection head 3 includes a negative pressure control unit 230 that controls the pressure (negative pressure) in the circulation path, a liquid supply unit 220 that is in fluid communication with the negative pressure control unit 230, and a liquid supply unit 220 that supplies and discharges ink to the liquid supply unit 220. It includes a liquid connection part 111 serving as an outlet and a housing 80. The recording medium 2 is not limited to cut paper, and may be a continuous roll medium. The liquid ejection head 3 is capable of full-color recording using cyan C, magenta M, yellow Y, and black K inks, and includes a liquid supply means, a main tank, and a buffer tank (which is a supply path for supplying liquid to the liquid ejection head 3). (see FIG. 2 described below) are fluidly connected. Furthermore, an electric control section that transmits electric power and ejection control signals to the liquid ejection head 3 is electrically connected to the liquid ejection head 3 . The liquid path and electrical signal path within the liquid ejection head 3 will be described later.

The recording apparatus 1000 is a liquid ejection recording apparatus in which a liquid such as ink is circulated between a tank and a liquid ejection head 3, which will be described later. The circulation mode is a first circulation mode in which two circulation pumps (for high pressure and low pressure) are operated on the downstream side of the liquid discharge head 3, and a first circulation mode in which two circulation pumps are operated on the upstream side of the liquid discharge head 3. There is a second circulation mode that circulates by moving (for high pressure and for low pressure). Hereinafter, the first circulation form and the second circulation form of this circulation will be explained.

(Explanation of first circulation form)
FIG. 2 is a schematic diagram showing a first circulation form of the 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, a buffer tank 1003, and the like. Note that in order to simplify the explanation, Figure 2 only shows the path through which one of the inks of cyan C, magenta M, yellow Y, and black K flows, but in reality, the paths for four colors are shown. A circulation path is provided in the liquid ejection head 3 and the recording apparatus main 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 sent to the liquid supply unit 220 of the liquid ejection head 3 via the liquid connection part 111 by the second circulation pump 1004. Supplied. Thereafter, the ink adjusted to two different negative pressures (high pressure, low pressure) by the negative pressure control unit 230 connected to the liquid supply unit 220 is divided into two flow paths, a high pressure side and a low pressure side, and circulates. The ink in the liquid ejection head 3 is circulated within the liquid ejection head by the action of a first circulation pump (high pressure side) 1001 and a first circulation pump (low pressure side) 1002 located downstream of the liquid ejection head 3, and is circulated through the liquid ejection head 111. The liquid is discharged from the liquid ejection head 3 via the liquid ejection head 3 and returned to the buffer tank 1003.

The buffer tank 1003, which is a sub-tank, is connected to the main tank 1006, has an atmosphere communication port (not shown) that communicates the inside of the tank with the outside, and can discharge air bubbles in the ink to the outside. A replenishment pump 1005 is provided between the buffer tank 1003 and the main tank 1006. The replenishment pump 1005 transfers ink consumed by ejecting (discharging) ink from the ejection opening of the liquid ejection head 3 to the buffer tank 1005 from the main tank 1006 during recording by ejecting ink or suction recovery.

The two first circulation pumps 1001 and 1002 draw out the liquid from the liquid connection part 111 of the liquid ejection head 3 and flow it into the buffer tank 1003. As the first circulation pump, a positive displacement pump having a quantitative liquid feeding capacity is preferable. Specific examples include tube pumps, gear pumps, diaphragm pumps, syringe pumps, etc., but for example, a general constant flow valve or relief valve may be disposed at the pump outlet to ensure a constant flow rate. When the liquid ejection head 3 is driven, the first circulation pump (high pressure side) 1001 and the first circulation pump (low pressure side) 1002 are operated to maintain a predetermined flow rate in the common supply channel 211 and the common recovery channel 212, respectively. Ink flows. By flowing ink in this manner, the temperature of the liquid ejection head 3 during recording is maintained at an optimal temperature. The predetermined flow rate when driving the liquid ejection head 3 is preferably set to a flow rate that can be maintained to such an extent that the temperature difference between each recording element substrate 10 in the liquid ejection head 3 does not affect the quality of the printed image. However, if the flow rate is set to be too large, the negative pressure difference will become large on each recording element substrate 10 due to the influence of pressure loss in the flow path within the liquid ejection unit 300, resulting in uneven density of images. Therefore, it is preferable to set the flow rate while taking into account the temperature difference and negative pressure difference between each recording element substrate 10.

Negative pressure control unit 230 is provided in a path between second circulation pump 1004 and liquid discharge unit 300. This negative pressure control unit 230 controls the pressure downstream of the negative pressure control unit 230 (that is, on the liquid ejection unit 300 side) even when the flow rate of ink in the circulation system fluctuates due to a difference in ejection amount per unit area. It operates to maintain a preset constant pressure. The two negative pressure control mechanisms constituting the negative pressure control unit 230 may be one that can control the pressure downstream of the negative pressure control unit 230 within a certain range of fluctuations around a desired set pressure. Any mechanism may be used. As an example, a mechanism similar to a so-called "reducing pressure regulator" can be adopted. In the circulation channel in this application example, the second circulation pump 1004 pressurizes the upstream side of the negative pressure control unit 230 via the liquid supply unit 220. In this way, the influence of the water head pressure of the buffer tank 1003 on the liquid ejection head 3 can be suppressed, so that the degree of freedom in the layout of the buffer tank 1003 in the printing apparatus 1000 can be increased.

The second circulation pump 1004 only needs to have a head pressure of a certain pressure or more within the range of the ink circulation flow rate used when driving the liquid ejection head 3, and a turbo pump, a positive displacement pump, etc. can be used. be. Specifically, a diaphragm pump or the like is applicable. Further, instead of the second circulation pump 1004, for example, a water head tank arranged with a certain water head difference with respect to the negative pressure control unit 230 may be used. As shown in FIG. 2, 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 setting side (denoted as H in FIG. 2) and the relatively low pressure setting side (denoted as L in FIG. 2) each pass through the liquid supply unit 220. It is connected to a common supply channel 211 and a common recovery channel 212 in the liquid discharge unit 300. The liquid ejection unit 300 is provided with a common supply channel 211, a common recovery channel 212, and individual channels 215 (individual supply channel 213, individual recovery channel 214) communicating with each recording element substrate. A negative pressure control mechanism H is connected to the common supply channel 211, and a negative pressure control mechanism L is connected to the common recovery channel 212, and a pressure difference is generated between the two common channels. Since the individual channels 215 communicate with the common supply channel 211 and the common recovery channel 212, part of the liquid passes through the internal channel of the recording element substrate 10 from the common supply channel 211. A flow (arrow in FIG. 2) is generated that flows into the common recovery channel 212.

In this way, in the liquid ejection unit 300, the liquid is allowed to flow through the common supply channel 211 and the common recovery channel 212, while some of the liquid passes through each recording element substrate 10. A flow occurs. Therefore, the heat generated in each recording element substrate 10 can be discharged to the outside of the recording element substrate 10 by the ink flowing through the common supply channel 211 and the common recovery channel 212. Furthermore, with this configuration, when the liquid ejection head 3 performs recording, it is possible to cause ink to flow even in the ejection ports and pressure chambers that are not ejecting. This reduces the viscosity of the ink that has thickened within the ejection port, thereby suppressing the thickening of the ink. Further, thickened ink and foreign matter in the ink can be discharged to the common recovery channel 212. Therefore, the liquid ejection head 3 of this application example can perform high-speed, high-quality recording.

(Explanation of second circulation form)
FIG. 3 is a schematic diagram showing a second circulation mode, which is a circulation mode different from the above-described first circulation mode, among the circulation paths applied to the recording apparatus of this application example. The main difference from the first circulation mode described above is that the two negative pressure control mechanisms that make up the negative pressure control unit 230 both control the pressure upstream of the negative pressure control unit 230 around a desired set pressure. The point is that it is controlled by fluctuations within a certain range. Furthermore, a difference from the first circulation mode is that the second circulation pump 1004 acts as a negative pressure source that reduces the pressure on the downstream side of the negative pressure control unit 230. Further, a first circulation pump (high pressure side) 1001 and a first circulation pump (low pressure side) 1002 are arranged on the upstream side of the liquid discharge head 3, and a negative pressure control unit 230 is arranged on the downstream side of the liquid discharge head 3. Another difference is that there are

In the second circulation mode, ink in the main tank 1006 is supplied to the buffer tank 1003 by the replenishment pump 1005. Thereafter, the ink is divided into two flow paths, and circulates in the 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 ejection head 3. The ink divided into two flow paths, high pressure side and low pressure side, is transferred to the liquid ejection head 3 via 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. supplied to Thereafter, the ink that has been circulated within the liquid ejection head by the action of the first circulation pump (high pressure side) 1001 and the first circulation pump (low pressure side) 1002 passes through the negative pressure control unit 230 and is transferred to the liquid via the liquid connection part 111. It is discharged from the discharge head 3. 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 controls pressure fluctuations on the upstream side of the negative pressure control unit 230 (i.e., on the liquid discharge unit 300 side) even if there is a fluctuation in the flow rate caused by a change in the discharge amount per unit area. is stabilized within a certain range around a preset pressure. In the circulation flow path of this application example, the second circulation pump 1004 pressurizes the downstream side of the negative pressure control unit 230 via the liquid supply unit 220. In this way, the influence of the water head pressure of the buffer tank 1003 on the liquid ejection head 3 can be suppressed, so that the range of choices for the layout of the buffer tank 1003 in the printing apparatus 1000 can be expanded. Instead of the second circulation pump 1004, for example, a water head tank arranged with a predetermined water head difference with respect to the negative pressure control unit 230 may be used. In the second circulation mode, like the first circulation mode, 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 setting side (denoted as H in FIG. 3) and the low pressure setting side (denoted as L in FIG. 3) are respectively connected to the liquid discharge unit 300 via the liquid supply unit 220. The common supply flow path 211 or the common recovery flow path 212 is connected to the common supply flow path 211 or the common recovery flow path 212. By making the pressure in the common supply flow path 211 relatively higher than the pressure in the common recovery flow path 212 using the two negative pressure adjustment mechanisms, the pressure inside the common supply flow path 211 and the individual flow paths 215 and each recording element substrate 10 is increased. A flow of liquid is generated that flows through the channels to the common recovery channel 212 .

In such a second circulation mode, the same liquid flow state as in the first circulation mode is obtained within the liquid discharge unit 300, but there are two advantages that are different from the first circulation mode. The first advantage is that in the second circulation mode, the negative pressure control unit 230 is disposed downstream of the liquid ejection head 3, so that dust and foreign matter generated from the negative pressure control unit 230 do not flow into the liquid ejection head 3. There is little concern that this will happen. The second advantage is that in the second circulation mode, the maximum required flow rate to be supplied from the buffer tank 1003 to the liquid ejection head 3 is smaller than in the first circulation mode. The reason is as follows.

The sum of the flow rates in the common supply channel 211 and the common recovery channel 212 when circulating during recording standby is defined as a flow rate A. The value of the flow rate A is defined as the minimum flow rate required to bring the temperature difference within the liquid ejection unit 300 within a desired range when adjusting the temperature of the liquid ejection head 3 during recording standby. Further, the ejection flow rate when ink is ejected from all the ejection ports of the liquid ejection unit 300 (at the time of all ejections) is defined as the flow rate F (ejection amount per ejection port x ejection frequency per unit time x number of ejection ports).

FIG. 4 is a schematic diagram showing the difference in the amount of ink flowing into the liquid ejection head 3 between the first circulation mode and the second circulation mode. FIG. 4(a) shows the standby state in the first circulation mode, and FIG. 4(b) shows the full discharge state in the first circulation mode. 4(c) to 4(f) show the second circulation flow path, and FIGS. 4(c) and 4(d) are cases where the flow rate F<flow rate A, and FIGS. 4(e) and (f) ) is a case where flow rate F>flow rate A, and respectively indicate the flow rate during standby and during full discharge.

In the case of the first circulation mode in which the first circulation pump 1001 and the first circulation pump 1002 having quantitative liquid feeding ability are arranged on the downstream side of the liquid ejection head 3 (FIGS. 4(a) and 4(b)), The total set flow rate of the first circulation pump 1001 and the first circulation pump 1002 is the flow rate A. This flow rate A makes it possible to control the temperature inside the liquid ejection unit 300 during standby. When the liquid ejection head 3 performs full ejection, the total set flow rate of the first circulation pump 1001 and the first circulation pump 1002 remains at the flow rate A. However, the maximum flow rate supplied to the liquid ejection head 3 is determined by the negative pressure generated by ejection in the liquid ejection head 3, and the flow rate F consumed by all ejection is added to the total set flow rate A. Therefore, the maximum value of the supply amount to the liquid ejection head 3 is the flow rate A+flow rate F since the flow rate F is added to the flow rate A (FIG. 4(b)).

On the other hand, in the case of the second circulation mode in which the first circulation pump 1001 and the first circulation pump 1002 are arranged upstream of the liquid ejection head 3 (FIGS. 4(c) to 4(f)), the recording standby state is The amount of supply to the liquid ejection head 3 that is sometimes required is the flow rate A, as in the first circulation mode. Therefore, in the second circulation mode in which the first circulation pump 1001 and the first circulation pump 1002 are arranged upstream of the liquid ejection head 3, when the flow rate A is larger than the flow rate F (Fig. 4(c), (d) )), the flow rate A is sufficient for the supply amount to the liquid ejection head 3 even during full ejection. At this time, the discharge flow rate from the liquid ejection head 3 becomes the flow rate A - the flow rate F (FIG. 4(d)). However, when the flow rate F is larger than the flow rate A (FIGS. 4(e) and 4(f)), the flow rate becomes insufficient when the flow rate A is the supply flow rate to the liquid ejection head 3 during full ejection. Therefore, when the flow rate F is larger than the flow rate A, it is necessary to set the supply amount to the liquid ejection head 3 at the flow rate F. At this time, when full ejection is performed, the flow rate F is consumed in the liquid ejection head 3, so that almost no flow rate is discharged from the liquid ejection head 3 (FIG. 4(f)). Note that when the flow rate F is greater than the flow rate A, and ejection is performed but not all of the liquid is ejected, the amount obtained by subtracting the amount consumed by ejection from the flow rate F is ejected from the liquid ejection head 3. Further, when the flow rate A and the flow rate F are equal, the flow rate A (or the flow rate F) is supplied to the liquid ejection head 3, and the flow rate F is consumed in the liquid ejection head 3. The discharge flow rate is almost no discharge.

In this way, in the case of the second circulation mode, the total value of the set flow rates of 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 value of the flow rate A or the flow rate F. . Therefore, as long as liquid discharge units 300 with the same configuration are used, the maximum value of the required supply amount in the second circulation mode (flow rate A or flow rate F) is the maximum value of the required supply flow rate in the first circulation mode (flow rate A + flow rate F) becomes smaller.

Therefore, in the case of the second circulation mode, the flexibility of applicable circulation pumps increases, such as using a low-cost circulation pump with a simple configuration, or reducing the load on a cooler (not shown) installed in the main body side path. This has the advantage that the cost of the recording apparatus can be reduced. This advantage becomes greater as the line head has a relatively larger value of flow rate A or flow rate F, and among line heads, the line head that is longer in the longitudinal direction is more beneficial.

However, on the other hand, the first circulation mode has some advantages over the second circulation mode. In other words, in the second circulation mode, the flow rate flowing through the liquid ejection unit 300 during recording standby is maximum, so the smaller the amount of ejection per unit area of an image (hereinafter also referred to as a low duty image), the more A high negative pressure is applied. Therefore, when the channel width is narrow and the negative pressure is high, high negative pressure is applied to the ejection port in low-duty images where unevenness is easily visible, so there are many so-called satellite droplets that are ejected along with the main ink droplets. There is a possibility that this may occur and the recording quality may deteriorate.

On the other hand, in the case of the first circulation mode, high negative pressure is applied to the ejection port when forming an image with a large amount of ejection per unit area (hereinafter also referred to as a high-duty image). It has the advantage that it is difficult to visually recognize even when it is used, and the effect on the image is small. A preferable selection between these two circulation forms can be made in light of the specifications of the liquid ejection head and the recording apparatus main body (ejection flow rate F, minimum circulation flow rate A, and in-head flow path resistance).

(Explanation of liquid ejection head configuration)
The configuration of the liquid ejection head 3 according to the first application example will be described. FIGS. 5A and 5B are perspective views showing the liquid ejection head 3 according to this application example. The liquid ejection head 3 has 15 recording element substrates 10 arranged in a straight line (arranged in-line) capable of ejecting inks of four colors cyan C/magenta M/yellow Y/black K from one recording element substrate 10. This is a line-type liquid ejection head. As shown in FIG. 5A, the liquid ejection head 3 has a signal input terminal 91 and a power supply terminal 92 electrically connected to each recording element substrate 10 via a flexible wiring board 40 and an electric wiring board 90. Be prepared. The signal input terminal 91 and the power supply terminal 92 are electrically connected to the control section of the printing apparatus 1000 and supply an ejection drive signal and the power necessary for ejection to the printing element substrate 10, respectively. By consolidating the wiring using the electric circuit in the electric wiring board 90, the number of signal input terminals 91 and power supply terminals 92 can be reduced compared to the number of recording element substrates 10. This reduces the number of electrical connections that need to be removed when assembling the liquid ejection head 3 to the recording apparatus 1000 or replacing the liquid ejection head. As shown in FIG. 5B, the liquid connecting portions 111 provided at both ends of the liquid ejection head 3 are connected to the liquid supply system of the recording apparatus 1000. As a result, inks of four colors cyan C/magenta M/yellow Y/black K are supplied from the supply system of the recording apparatus 1000 to the liquid ejection head 3, and the ink that has passed through the liquid ejection head 3 is supplied to the supply system of the recording apparatus 1000. It is set to be collected. In this way, the ink of each color can be circulated through the path of the recording apparatus 1000 and the path of the liquid ejection head 3.

FIG. 6 is an exploded perspective view showing each component or unit that constitutes the liquid ejection head 3. As shown in FIG. A liquid discharge unit 300, a liquid supply unit 220, and an electric wiring board 90 are attached to the housing 80. The liquid supply unit 220 is provided with a liquid connection part 111 (see FIG. 3), and the inside of the liquid supply unit 220 is connected to each opening of the liquid connection part 111 in order to remove foreign matter from the supplied ink. Filters 221 for each color (see FIGS. 2 and 3) are provided. The two liquid supply units 220 are each provided with filters 221 for two colors. The liquid that has passed through the filter 221 is supplied to a negative pressure control unit 230 arranged on the liquid supply unit 220 corresponding to each color. The negative pressure control unit 230 is a unit consisting of negative pressure control valves for each color.The negative pressure control unit 230 is a unit consisting of negative pressure control valves for each color.The negative pressure control unit 230 is a unit that has valves and spring members provided inside each of the negative pressure control valves. (The supply system on the upstream side of the liquid ejection head 3) changes in pressure loss are significantly attenuated. This allows the negative pressure control unit 230 to stabilize changes in negative pressure on the downstream side (liquid discharge unit 300 side) of the negative pressure control unit within a certain range. The negative pressure control unit 230 of each color includes two negative pressure control valves for each color, as described in FIG. 2 . The two negative pressure control valves are set to different control pressures, and the high pressure side is connected to the common supply channel 211 (see FIG. 2) in the liquid discharge unit 300, and the low pressure side is connected to the common recovery channel 212 (see FIG. 2) and the liquid supply. It communicates via unit 220.

The casing 80 includes a liquid ejection unit support section 81 and an electric wiring board support section 82, and supports the liquid ejection unit 300 and the electric wiring board 90, and also ensures the rigidity of the liquid ejection head 3. The electrical wiring board support part 82 is for supporting the electrical wiring board 90, and is fixed to the liquid ejection unit support part 81 with screws. The liquid ejection unit support section 81 has the role of correcting warpage and deformation of the liquid ejection unit 300 and ensuring relative positional accuracy of the plurality of recording element substrates 10, thereby suppressing streaks and unevenness in the recorded material. . Therefore, it is preferable that the liquid discharge unit support part 81 has sufficient rigidity, and the material thereof is preferably a metal material such as SUS or aluminum, or a ceramic such as alumina. The liquid discharge unit support portion 81 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 70 that constitutes the liquid discharge unit 300 via the joint rubber.

The liquid ejection unit 300 includes a plurality of ejection modules 200 and a flow path member 210, and a cover member 130 is attached to the surface of the liquid ejection unit 300 on the recording medium side. Here, the cover member 130 is a member having a frame-shaped surface provided with a long opening 131 as shown in FIG. A stop member 110 (see FIG. 10 described later) is exposed. The frame around the opening 131 functions as a contact surface for a cap member that caps the liquid ejection head 3 during recording standby. For this reason, a closed space is formed when capping by applying an adhesive, a sealing material, a filler, etc. along the periphery of the opening 131 to fill in the irregularities and gaps on the discharge port surface of the liquid discharge unit 300. It is preferable to do so.

Next, the configuration of the flow path member 210 included in the liquid ejection unit 300 will be described. As shown in FIG. 6, the flow path member 210 is a stack of a first flow path member 50, a second flow path member 60, and a third flow path member 70, and allows the liquid supplied from the liquid supply unit 220 to flow through the flow path member 210. Distribute to each discharge module 200. Further, the flow path member 210 is a flow path member for returning the liquid circulating from the discharge module 200 to the liquid supply unit 220. The flow path member 210 is fixed to the liquid ejection unit support portion 81 with screws, thereby suppressing warpage and deformation of the flow path member 210.

FIGS. 7A to 7F are diagrams showing the front and back surfaces of each of the first to third flow path members. 7(a) shows the side of the first channel member 50 on which the discharge module 200 is mounted, and FIG. 7(f) shows the surface of the third channel member 70 on the side where the discharge module 200 is mounted. Indicates the side that comes into contact. The first flow path member 50 and the second flow path member 60 are joined so that the contact surfaces of the respective flow path members, shown in FIG. 7(b) and FIG. 7(c), face each other, and the second flow path member The member and the third flow path member are joined so that the contact surfaces of the respective flow path members shown in FIG. 7(d) and FIG. 7(e) face each other. By joining the second flow path member 60 and the third flow path member 70, eight grooves extending in the longitudinal direction of the flow path members are formed from the common flow grooves 62 and 71 formed in each flow path member. Common channels (211a, 211b, 211c, 211d, 212a, 212b, 212c, 212d) are formed. As a result, a set of a common supply channel 211 and a common recovery channel 212 is formed in the channel member 210 for each color. Ink is supplied to the liquid ejection head 3 from the common supply channel 211, and the ink supplied to the liquid ejection head 3 is recovered by the common recovery channel 212. The communication port 72 (see FIG. 7(f)) of the third flow path member 70 communicates with each hole of the joint rubber 100, and is in fluid communication with the liquid supply unit 220 (see FIG. 6). A communication port 61 (a communication port 61-1 communicating with the common supply channel 211 and a communication port 61-2 communicating with the common recovery channel 212) is provided on the bottom surface of the common channel groove 62 of the second channel member 60. A plurality of grooves are formed and communicate with one end portion of the individual channel groove 52 of the first channel member 50 . A communication port 51 is formed at the other end of the individual flow path groove 52 of the first flow path member 50, and fluidly communicates with the plurality of discharge modules 200 via the communication port 51. The individual channel grooves 52 make it possible to concentrate the channels toward the center of the channel member.

It is preferable that the first to third flow path members are made of a material that is corrosion resistant to liquid and has a low coefficient of linear expansion. As the material, for example, a composite material (resin material) in which alumina, LCP (liquid crystal polymer), PPS (polyphenylsulfide), or PSF (polysulfone) is added as a base material and inorganic filler such as silica particles or fiber is used is preferably used. be able to. The flow path member 210 may be formed by stacking three flow path members and adhering them to each other, or if a resin composite resin material is selected as the material, a joining method by welding may be used.

FIG. 8 shows the α part of FIG. 7(a), in which the flow path in the flow path member 210 formed by joining the first to third flow path members is connected to the first flow path member 50, FIG. 2 is a partially enlarged perspective view from the side of the surface on which the discharge module 200 is mounted. The common supply channel 211 and the common recovery channel 212 are arranged alternately from the channels at both ends. Here, the connection relationship of each channel in the channel member 210 will be explained.

The channel member 210 is provided with a common supply channel 211 (211a, 211b, 211c, 211d) and a common recovery channel 212 (212a, 212b, 212c, 212d) extending in the longitudinal direction of the liquid ejection head 3 for each color. It is being A plurality of individual supply channels 213 (213a, 213b, 213c, 213d) formed by individual channel grooves 52 are connected to the common supply channel 211 of each color via a communication port 61. Further, a plurality of individual recovery channels 214 (214a, 214b, 214c, 214d) formed by individual channel grooves 52 are connected to the common recovery channel 212 for each color via communication ports 61. With such a flow path configuration, ink can be concentrated from each common supply flow path 211 to the recording element substrate 10 located in the center of the flow path member via the individual supply flow paths 213. Further, ink can be collected from the recording element substrate 10 into each common collection channel 212 via the individual recovery channels 214.

FIG. 9 is a cross-sectional view taken along line IX-IX in FIG. Each individual recovery channel (214a, 214c) communicates with the discharge module 200 via the communication port 51. In FIG. 9, only the individual recovery channels (214a, 214c) are shown, but in another cross section, the individual supply channel 213 and the discharge module 200 communicate with each other as shown in FIG. A flow path is formed in the support member 30 and the recording element substrate 10 included in each ejection module 200 for supplying ink from the first flow path member 50 to the recording element 15 provided on the recording element substrate 10. . Further, a flow path is formed in the support member 30 and the recording element substrate 10 for recovering (recirculating) part or all of the liquid supplied to the recording element 15 to the first flow path member 50.

Here, the common supply channel 211 of each color is connected to the negative pressure control unit 230 (high pressure side) of the corresponding color via the liquid supply unit 220, and the common recovery channel 212 is connected to the negative pressure control unit 230 (high pressure side) of the corresponding color. (low pressure side) via a liquid supply unit 220. This negative pressure control unit 230 is configured to generate a pressure difference (pressure difference) between the common supply channel 211 and the common recovery channel 212. Therefore, as shown in FIGS. 8 and 9, in the liquid ejection head of this application example in which each flow path is connected, the common supply flow path 211 to individual supply flow path 213 to recording element substrate 10 to individual A flow is generated that sequentially flows from the recovery channel 214 to the common recovery channel 212.

(Description of discharge module)
FIG. 10(a) is a perspective view showing one discharge module 200, and FIG. 10(b) is an exploded view thereof. As a method for manufacturing the ejection module 200, first, the recording element substrate 10 and the flexible wiring board 40 are bonded onto the support member 30 in which the liquid communication port 31 is provided in advance. Thereafter, the terminal 16 on the recording element substrate 10 and the terminal 41 on the flexible wiring board 40 are electrically connected by wire bonding, and then the wire bonding part (electrical connection part) is covered with a sealing member 110 for sealing. . Terminals 42 of the flexible wiring board 40 on the side opposite to the recording element substrate 10 are electrically connected to connection terminals 93 (see FIG. 6) of the electric wiring board 90. The support member 30 is a support body that supports the recording element substrate 10, and is also a flow path member that fluidly communicates the recording element substrate 10 and the flow path member 210, and therefore has a high flatness and a sufficiently high flatness. It is preferable to use a material that can be reliably bonded to the recording element substrate. The material is preferably alumina or resin material, for example.

(Explanation of structure of recording element substrate)
11(a) shows a plan view of the surface of the recording element substrate 10 on which the ejection ports 13 are formed, and FIG. 11(b) shows an enlarged view of the portion indicated by A in FIG. 11(a). , FIG. 11(c) shows a plan view of the back side of FIG. 11(a). Here, the configuration of the recording element substrate 10 in this application example will be described. As shown in FIG. 11A, four ejection port arrays corresponding to each ink color are formed in the ejection port forming member 12 of the recording element substrate 10. Note that hereinafter, the direction in which the ejection port array in which the plurality of ejection ports 13 are arranged extends will be referred to as the "ejection port array direction." As shown in FIG. 11(b), a recording element 15, which is a heat generating element for foaming the liquid using thermal energy, is arranged at a position corresponding to each ejection port 13. A pressure chamber 23 having a recording element 15 therein is defined by the partition wall 22 . The recording element 15 is electrically connected to a terminal 16 by electrical wiring (not shown) provided on the recording element substrate 10. The recording element 15 generates heat and boils the liquid based on pulse signals input from the control circuit of the recording apparatus 1000 via the electric wiring board 90 (see FIG. 6) and the flexible wiring board 40 (see FIG. 10). let The liquid is discharged from the discharge port 13 by the bubbling force caused by this boiling. As shown in FIG. 11(b), along each discharge port row, a liquid supply path 18 extends on one side, and a liquid recovery path 19 extends on the other side. The liquid supply path 18 and the liquid recovery path 19 are flow paths extending in the direction of the ejection port array provided on the recording element substrate 10, and are connected to the ejection port 13 through the supply port 17a and the recovery port 17b, which are liquid paths. It's communicating.

As shown in FIG. 11(c), a sheet-like lid member (resin film) 20 made of a resin material is laminated on the back side of the surface of the recording element substrate 10 on which the ejection ports 13 are formed. is provided with a plurality of openings 21 that communicate with the liquid supply path 18 and the liquid recovery path 19. In this application example, for each liquid supply path 18, which is a common flow path extending along the longitudinal direction of the recording element substrate 10, three supply and recovery paths also extend along the longitudinal direction. Two openings 21 are provided in the lid member 20 for one liquid recovery path 19. In the present invention, the number of openings 21 is not limited to this. For example, two supply side openings 21 may be provided for one liquid supply path 18 and one recovery side opening 21 may be provided for one liquid recovery path 19. Considering the pressure loss in the flow path, it is preferable that either the liquid supply path 18 or the liquid recovery path 19 has at least two or more openings.

As shown in FIG. 11(b), each opening 21 of the lid member 20 communicates with the plurality of communication ports 51 shown in FIG. 7(a). The lid member 20 preferably has sufficient corrosion resistance against liquid, and from the viewpoint of preventing color mixture, high precision is required in the shape and position of the opening 21. For this reason, it is preferable to use a photosensitive resin material or a silicon plate as the material of the lid member 20, and to provide the opening 21 by a photolithography process. In this way, the lid member 20 changes the pitch of the flow path using the openings 21, and in consideration of pressure loss, it is desirable that the lid member 20 be thin, and preferably made of a photosensitive resin film.

FIG. 12 is a perspective view showing a cross section of the recording element substrate 10 and the lid member 20 taken along the line XII-XII in FIG. 11(a). Here, the flow of liquid within the recording element substrate 10 will be explained. The lid member 20 has a function as a lid that forms part of the walls of the liquid supply path 18 and the liquid recovery path 19 formed on the substrate 11 of the recording element substrate 10 . The recording element substrate 10 includes a substrate 11 made of Si and an ejection port forming member 12 made of photosensitive resin, which are laminated together, and a lid member 20 is bonded to the back surface of the substrate 11 . A recording element 15 is formed on one side of the substrate 11 (see FIG. 11), and a liquid supply path 19 and a liquid recovery path 18 extending along the ejection port array are formed on the back side of the substrate 11. A groove is formed. The liquid supply channel 18 and the liquid recovery channel 19 formed by the substrate 11 and the lid member 20 are connected to a common supply channel 211 and a common recovery channel 212 in the channel member 210, respectively, and the liquid supply channel 18 A differential pressure is generated between the liquid recovery path 19 and the liquid recovery path 19. When recording is performed by ejecting liquid from the ejection ports 13, at the ejection ports that are not ejecting, this pressure difference causes the liquid in the liquid supply path 18 provided in the substrate 11 to flow into the supply ports 17a, The liquid flows to the liquid recovery path 19 via the pressure chamber 23 and the recovery port 17b (arrow C in FIG. 12). Due to this flow, thickened ink, bubbles, foreign matter, etc. generated by evaporation from the ejection ports 13 can be collected into the liquid recovery path 19 in the ejection ports 13 and the pressure chambers 23 when recording is stopped. Further, thickening of the ink in the ejection port 13 and the pressure chamber 23 can be suppressed. The liquid collected into the liquid recovery path 19 is transferred to the communication port 51 in the channel member 210, the individual recovery channel 214, and the common recovery channel through the opening 21 of the lid member 20 and the liquid communication port 31 of the support member 30 (see FIG. 10b). The liquid is collected in the order of the flow path 212 and is collected into the collection path of the recording device 1000. That is, the liquid supplied from the recording apparatus main body to the liquid ejection head 3 flows, is supplied and collected in the following order.

The liquid first flows into the liquid ejection head 3 from the liquid connection portion 111 of the liquid supply unit 220 . The liquid flows through the joint rubber 100, the communication port 72 and common channel groove 71 provided in the third channel member, the common channel groove 62 and communication port 61 provided in the second channel member, and the first channel. It is supplied to the individual channel grooves 52 and the communication ports 51 provided in the member in this order. Thereafter, the liquid is supplied to the pressure chamber 23 through the liquid communication port 31 provided in the support member 30, the opening 21 provided in the lid member 20, the liquid supply path 18 provided in the substrate 11, and the supply port 17a in this order. Among the liquids supplied to the pressure chamber 23, the liquid that is not discharged from the discharge port 13 is collected through the recovery port 17b and the liquid recovery path 19 provided in the substrate 11, the opening 21 provided in the lid member 20, and the support member 30. The liquid flows sequentially through the liquid communication port 31 provided in the. Thereafter, the liquid is passed through the communication port 51 and individual channel groove 52 provided in the first channel member, the communication port 61 and common channel groove 62 provided in the second channel member, and the third channel member 70. The water flows through the common flow groove 71, the communication port 72, and the joint rubber 100 in this order. Then, the liquid flows from the liquid connection part 111 provided in the liquid supply unit 220 to the outside of the liquid ejection head 3.

In the first circulation mode shown in FIG. 2, the liquid flowing from the liquid connection part 111 is supplied to the joint rubber 100 after passing through the negative pressure control unit 230. In addition, in the second circulation mode shown in FIG. 3, the liquid recovered from the pressure chamber 23 passes through the joint rubber 100, and then passes through the negative pressure control unit 230 from the liquid connection part 111 to the outside of the liquid ejection head. flow to. Furthermore, not all the liquid that has flowed in from one end of the common supply channel 211 of the liquid discharge unit 300 is supplied to the pressure chamber 23 via the individual supply channel 213a. In other words, some liquid flows from one end of the common supply channel 211 to the liquid supply unit 220 from the other end of the common supply channel 211 without flowing into the individual supply channel 213a. In this way, by providing a path through which the liquid flows without passing through the recording element substrate 10, even when the recording element substrate 10 is equipped with a fine flow path having a large flow resistance as in this application example, the liquid can flow without passing through the recording element substrate 10. The backflow of the circulating flow can be suppressed. In this way, in the liquid ejection head 3 of this application example, it is possible to suppress the increase in the viscosity of the liquid near the pressure chamber 23 and the ejection port, so it is possible to suppress the deviation and non-ejection of ejection, and as a result, High-quality recording can be performed.

(Explanation of positional relationship between recording element substrates)
FIG. 13 is a partially enlarged plan view showing adjacent portions of recording element substrates in two adjacent ejection modules. In this application example, a substantially parallelogram recording element substrate is used. Among parallelograms, the present invention is particularly suitable for parallelograms such as the one shown in FIG. 13, in which the angles between adjacent sides are not 90 degrees. Each ejection port array (14a to 14d) in which ejection ports 13 are arranged on each recording element substrate 10 is arranged so as to be inclined at a constant angle with respect to the longitudinal direction of the liquid ejection head 3. In the ejection port arrays in adjacent portions of the recording element substrates 10, at least one ejection port overlaps in the recording medium conveyance direction. In FIG. 13, the two discharge ports on line D are in an overlapping relationship with each other. With such an arrangement, even if the position of the recording element substrate 10 deviates from a predetermined position, black lines and white spots in the recorded image can be made less noticeable by controlling the drive of the overlapping ejection ports. Even when a plurality of recording element substrates 10 are arranged in a straight line (in-line) instead of in a staggered arrangement, the configuration shown in FIG. It is possible to take measures against black lines and white spots at the joints between the substrates 10. In this application example, the main plane of the recording element substrate is a parallelogram, but it is not limited to this. For example, even if a recording element substrate of a rectangular, trapezoidal, or other shape is used, the configuration of the present invention can be preferably applied. Can be applied.

(Second application example)
Hereinafter, the configurations of a liquid ejection recording apparatus 2000 and a liquid ejection head 2003 according to a second application example of the present invention will be described with reference to the drawings. In the following description, only the parts that are different from the first application example will be mainly explained, and the description of the same parts as the first application example will be omitted.

(Description of liquid ejection recording device)
FIG. 21 is a diagram showing a liquid ejection recording apparatus 2000 that performs printing by ejecting liquid to which this application example can be applied. The recording apparatus 2000 of this application example performs full-color recording on a recording medium by arranging four single-color liquid ejection heads 2003 in parallel, each corresponding to each ink of cyan C, magenta M, yellow Y, and black K. is different from the first application example. Whereas in the first application example, the number of ejection port rows that can be used per color is one, in this application example, the number of ejection port rows that can be used per one color is 20 rows. Therefore, by appropriately distributing print data to a plurality of ejection port arrays and performing printing, very high-speed printing becomes possible. Furthermore, even if there is an ejection port that fails to eject, reliability is improved by performing complementary ejection from ejection ports in other rows located at positions corresponding to the print medium transport direction with respect to that ejection port. It is suitable for commercial records, etc. Similarly to the first application example, the supply system of the printing apparatus 2000, the buffer tank 1003 (see FIGS. 2 and 3), and the main tank 1006 (see FIGS. 2 and 3) are connected to each liquid ejection head 2003. connected. Further, each liquid ejection head 2003 is electrically connected to an electric control unit that transmits electric power and ejection control signals to the liquid ejection head 2003.

(Explanation of circulation route)
Similar to the first application example, the first and second circulation forms shown in FIG. 2 or 3 can be used as the circulation form of the liquid between the printing apparatus 2000 and the liquid ejection head 2003.

(Explanation of liquid ejection head structure)
FIGS. 14A and 14B are perspective views showing a liquid ejection head 2003 according to this application example. Here, the structure of the liquid ejection head 2003 according to this application example will be described. The liquid ejection head 2003 is a liquid ejection type line type liquid ejection head that includes 16 recording element substrates 2010 arranged in a straight line in the longitudinal direction of the liquid ejection head 2003 and is capable of printing with one type of liquid. . The liquid ejection head 2003 includes a liquid connection section 111, a signal input terminal 91, and a power supply terminal 92, as in the first application example. However, since the liquid ejection head 2003 of this application example has more ejection port arrays than the first application example, the signal output terminal 91 and the power supply terminal 92 are arranged on both sides of the liquid ejection head 2003. This is to reduce voltage drop and signal transmission delay occurring in the wiring section provided on the recording element substrate 2010.

FIG. 15 is a perspective exploded view showing the liquid ejection head 2003, and shows each component or unit constituting the liquid ejection head 2003 divided according to its function. The role of each unit and member and the order of liquid distribution within the liquid ejection head are basically the same as in the first application example, but the function of ensuring the rigidity of the liquid ejection head is different. In the first application example, the liquid ejection head rigidity was mainly ensured by the liquid ejection unit support part 81, but in the liquid ejection head 2003 of the second application example, the second flow path member 2060 included in the liquid ejection unit 2300 This ensures the rigidity of the liquid ejection head. The liquid ejection unit support section 81 in this application example is connected to both ends of the second flow path member 2060, and this liquid ejection unit 2300 is mechanically coupled to the carriage of the recording apparatus 2000, and the liquid ejection head 2003 is connected to both ends of the second flow path member 2060. positioning. The liquid supply unit 2220 including the negative pressure control unit 2230 and the electric wiring board 90 are coupled to the liquid discharge unit support 81. Each of the two liquid supply units 2220 has a built-in filter (not shown).

The two negative pressure control units 2230 are set to control pressure at different, relatively high and low negative pressures. In addition, as shown in FIGS. 14 and 15, when negative pressure control units 2230 are installed at both ends of the liquid ejection head 2003 for the high pressure side and the low pressure side, a common supply extending in the longitudinal direction of the liquid ejection head 2003 is provided. The liquid flows in the channel and the common recovery channel oppose each other. In such a configuration, heat exchange is promoted between the common supply flow path and the common recovery flow path, and the temperature difference within the two common flow paths is reduced. This has the advantage that the temperature difference between the plurality of recording element substrates 2010 provided along the common flow path is reduced, and recording unevenness due to the temperature difference is less likely to occur.

Next, details of the channel member 2210 of the liquid ejection unit 2300 will be described. As shown in FIG. 15, the flow path member 2210 is a stack of a first flow path member 2050 and a second flow path member 2060, and distributes the liquid supplied from the liquid supply unit 2220 to each discharge module 2200. do. Further, the flow path member 2210 functions as a flow path member for returning the liquid circulating from the discharge module 2200 to the liquid supply unit 2220. The second flow path member 2060 of the flow path member 2210 is a flow path member in which a common supply flow path and a common recovery flow path are formed, and also has a function of mainly responsible for the rigidity of the liquid ejection head 2003. Therefore, it is preferable that the material of the second flow path member 2060 has sufficient corrosion resistance against liquids and high mechanical strength. Specifically, SUS, Ti, alumina, etc. can be used.

FIG. 16(a) is a diagram showing the surface of the first flow path member 2050 on which the discharge module 2200 is mounted, and FIG. 16(b) is a diagram showing the back surface of the first flow path member 2050. FIG. Unlike the first application example, the first flow path member 2050 in this application example has a plurality of members corresponding to each discharge module 2200 arranged adjacently. By adopting such a divided structure, multiple modules can be arranged to correspond to the length of the liquid ejection head 2003, so it is possible to use a relatively long scale that corresponds to, for example, B2 size and longer. It can be particularly suitably applied to a liquid ejection head. As shown in FIG. 16(a), the communication port 51 of the first flow path member 2050 is in fluid communication with the discharge module 2200, and as shown in FIG. The communication port 53 fluidly communicates with the communication port 61 of the second flow path member 2060. 16(c) shows the surface of the second flow path member 60 that comes into contact with the first flow path member 2050, and FIG. 16(d) shows a cross section of the second flow path member 60 at the center in the thickness direction. FIG. 16E is a diagram showing the surface of the second flow path member 2060 that comes into contact with the liquid supply unit 2220. The functions of the flow path and communication port of the second flow path member 2060 are the same as those for one color in the first application example. One of the common channel grooves 71 of the second channel member 2060 is a common supply channel 2211 shown in FIG. 17, which will be described later, and the other is a common recovery channel 2212. The liquid is supplied from one end to the other. This application example differs from the first application example in that the liquid flows in the common supply channel 2211 and the common recovery channel 2212 are in opposite directions.

FIG. 17 is a perspective view showing the liquid connection relationship between the recording element substrate 2010 and the flow path member 2210. A pair of common supply channels 2211 and common recovery channels 2212 extending in the longitudinal direction of the liquid ejection head 2003 are provided in the channel member 2210. The communication port 61 of the second flow path member 2060 is aligned and connected to the individual communication port 53 of the first flow path member 2050, and the communication port 61 is connected to the common supply flow path 2211 of the second flow path member 2060 through the communication port 61. A liquid supply flow path communicating with the communication port 51 of the first flow path member 2050 is formed. Similarly, a liquid supply path is also formed that communicates from the communication port 72 of the second flow path member 2060 to the communication port 51 of the first flow path member 2050 via the common recovery flow path 2212.

FIG. 18 is a cross-sectional view taken along line XVIII-XVIII in FIG. 17. The common supply channel 2211 is connected to the discharge module 2200 via the communication port 61, the individual communication port 53, and the communication port 51. Although not shown in FIG. 18, it is apparent with reference to FIG. 17 that in another cross-section, the common recovery channel 2212 is connected to the discharge module 2200 by a similar route. Similar to the first application example, each ejection module 2200 and recording element substrate 2010 are formed with a flow path that communicates with each ejection port, so that some or all of the supplied liquid can stop ejection operation. It is designed so that it can be circulated through the discharge port. Similarly to the first application example, the common supply channel 2211 is connected to the negative pressure control unit 2230 (high pressure side), and the common recovery channel 2212 is connected to the negative pressure control unit 2230 (low pressure side) and the liquid supply unit 2220. connected. Therefore, the differential pressure causes a flow to flow from the common supply channel 2211 through the pressure chambers of the recording element substrate 2010 to the common recovery channel 2212.

(Description of discharge module)
FIG. 19(a) is a perspective view showing one discharge module 2200, and FIG. 19(b) is an exploded view thereof. The difference from the first application example is that a plurality of terminals 16 are arranged on both sides of the recording element substrate 2010 along the direction of the plurality of ejection port arrays (each long side of the recording element substrate 2010). be. Accordingly, two flexible wiring boards 40 electrically connected to the recording element substrate 2010 are also arranged for one recording element substrate 2010. This is because the number of ejection opening rows provided on the recording element substrate 2010 is 20, which is significantly more than the 8 rows in the first application example, and the maximum distance from the terminal 16 to the recording element is shortened. This is to reduce voltage drop and signal delay occurring in the wiring section within the recording element substrate 2010. Further, the liquid communication port 31 of the support member 2030 is provided in the recording element substrate 2010 and opens so as to straddle all the ejection port arrays. Other points are similar to the first application example.

(Explanation of structure of recording element substrate)
20(a) is a schematic diagram of the surface of the recording element substrate 2010 on which the ejection ports 13 are arranged, and FIG. 20(c) is a schematic diagram showing the back surface of the surface of FIG. 20(a). FIG. 20(b) is a schematic diagram showing the surface of the recording element substrate 2010 when the lid member 2020 provided on the back side of the recording element substrate 2010 in FIG. 20(c) is removed. As shown in FIG. 20(b), liquid supply paths 18 and liquid recovery paths 19 are alternately provided on the back surface of the recording element substrate 2010 along the ejection port array direction. Although the number of ejection port rows is significantly increased compared to the first application example, the essential difference from the first application example is that the terminals 16 are arranged in the direction of the ejection port rows of the recording element substrate as described above. They are placed on both sides along the line. A set of liquid supply passages 18 and liquid recovery passages 19 are provided for each discharge port row, and an opening 21 that communicates with the liquid communication port 31 of the support member 2030 is provided in the lid member 2020. , the basic configuration is the same as the first application example.

Note that the description of the above application examples does not limit the scope of the present invention. As an example, in this application example, a thermal method is described in which a heating element generates bubbles to eject liquid, but the present invention is also applied to liquid ejection heads that employ a piezo method and various other liquid ejection methods. be able to.

In this application example, a liquid ejection recording apparatus (recording apparatus) in which a liquid such as ink is circulated between a tank and a liquid ejection head has been described, but other forms may be used. Other forms include, for example, a form in which the ink in the pressure chamber is made to flow by providing two tanks on the upstream side and the downstream side of the liquid ejection head and flowing the ink from one tank to the other tank without circulating the ink. It may be.

Furthermore, in this application example, a so-called line-type liquid ejection head having a length corresponding to the width of the recording medium is used, but a so-called serial-type liquid ejection head that performs recording while scanning the recording medium is also used. The present invention can also be applied to. An example of a serial liquid ejection head is a configuration in which one printing element substrate for ejecting black ink and one printing element substrate for ejecting color ink are mounted, but the present invention is not limited to this. In other words, a short liquid ejection head shorter than the width of the recording medium is created, in which a plurality of recording element substrates are arranged so that the ejection ports overlap in the direction of the ejection port array, and the head is scanned with respect to the recording medium. It may be.

(First embodiment)
Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. Note that since the basic configuration of this embodiment is the same as that of the application example described above, only the characteristic configuration will be described below.

DESCRIPTION OF THE PREFERRED EMBODIMENTS A liquid ejection head and a liquid ejection apparatus according to embodiments of the present invention will be described below with reference to the drawings. In each embodiment below, a liquid ejection head that ejects liquid (hereinafter also referred to as ink), a liquid ejection apparatus, and a manufacturing method will be described with specific configurations, but the present invention is not limited thereto. The liquid ejection head, liquid ejection device, and manufacturing method of the present invention can be applied to devices such as printers, copiers, facsimiles with communication systems, word processors with printer sections, and even industrial recording devices that are combined with various processing devices. Applicable. For example, it can be used for purposes such as biochip production and electronic circuit recording.

Furthermore, since the embodiments described below are appropriate specific examples of the present invention, various technically preferable limitations are attached thereto. However, as long as the idea of the present invention is followed, the present embodiment is not limited to the embodiments of this specification or other specific methods.

(Recording element substrate and lid member)
FIG. 22 is a diagram showing the recording element substrate 10 and the lid member 20 in this embodiment. The lid member 20 is a member that covers a flow path formed on the back surface of the recording element substrate 10 (the surface opposite to the surface provided with the ejection port forming member 12), and a third flow path layer to be described later is formed therein. ing. In the present invention, the recording element substrate 10 and the lid member 20 are both processed in the form of a wafer in a wafer process, and then are formed by being divided.

(Example of configuration of liquid ejection head)
FIGS. 23(a) to 23(e) are perspective views showing the liquid ejection head. The liquid ejection head in FIG. 23A includes one recording element substrate 10, and the support member 30 and the recording element substrate 10 are arranged on the first flow path member 50. This liquid ejection head is used in a so-called serial scan type liquid ejection recording apparatus. This liquid ejection recording device performs a printing scan in which ink is ejected from the ejection ports while moving the liquid ejection head in the main scanning direction in the direction of arrow An image is recorded on the recording medium by repeating the conveyance operation. The main scanning direction is a direction that intersects (orthogonally in this example) the first direction in which the ejection port array 14 extends.

The liquid ejection heads shown in FIGS. 23(b) and 23(c) are each long line heads in which a plurality of recording element substrates 10 are arranged in a staggered manner. In the configuration of FIG. 23(b), the first flow path member 50 is disposed in common with the plurality of recording element substrates 10, and in the configuration of FIG. 23(c), the first flow path member 50 is They are individually arranged for each recording element substrate 10. Such a liquid ejection head is used in a so-called full line type liquid ejection recording apparatus. The liquid ejection recording device continuously transports the recording medium in the direction of arrow Y, which intersects (orthogonally in this example) the first direction in which the ejection port array 14 extends, and ejects liquid at a fixed position. Images are continuously recorded on a recording medium by ejecting ink from a head.

The liquid ejection head shown in FIGS. 23(d) and 23(e) is a long line head in which recording element substrates 10 are arranged in a line, and is used in a so-called full line type liquid ejection recording apparatus. In the configuration of FIG. 23(d), the first flow path member 50 is disposed in common with the plurality of recording element substrates 10, and in the configuration of FIG. 23(e), the first flow path member 50 is They are individually arranged for each recording element substrate 10. It is desirable that the recording element substrate 10 in such a liquid ejection head has a shape similar to that of the fourth embodiment described later.

(recording device)
FIG. 24 is a diagram showing an outline and flow path configuration of a liquid ejection recording apparatus (liquid ejection apparatus) to which the liquid ejection head of the present invention can be applied. The recording apparatus shown in FIG. 24(a) is a serial scan type recording apparatus that uses, as the liquid ejection head 3, a liquid ejection head having the configuration as shown in FIG. 23(a) described above. The chassis 1010 is made up of a plurality of plate-shaped metal members having a predetermined rigidity, and forms the skeleton of this recording apparatus. The chassis 1010 is assembled with a feeding section 4, a conveying section 1, and a carriage 5 that mounts the liquid ejection head 3 and is movable back and forth in the main scanning direction of arrow X. The main scanning direction is a direction that intersects (orthogonally in this example) the direction in which the ejection port arrays in the liquid ejection head 3 extend. The feeding unit 4 automatically feeds a sheet-like recording medium (not shown) into the recording apparatus, and the conveying unit 1 transports the recording medium fed one by one from the feeding unit 4 in the direction of arrow Y. It is transported in the sub-scanning direction. The sub-scanning direction is a direction that intersects (orthogonally in this example) the main-scanning direction. Such a printing apparatus performs a printing scan in which ink is ejected from the ejection openings of the liquid ejection head 3 while moving the liquid ejection head 3 together with the carriage 5 in the main scanning direction, and a transport operation in which the printing medium is transported in the sub-scanning direction. By repeating this process, an image is recorded on the recording medium. Ink is supplied to the liquid ejection head 3 from an ink tank (not shown).

The recording apparatus shown in FIG. 24(b) is a full-line liquid ejection head using the elongated liquid ejection head 3 as shown in FIGS. 23(b), (c), (d), and (e) described above. , a conveying section 1 that continuously conveys a sheet (recording medium) 2 in the direction of arrow Y. As the conveyance unit 1, in addition to the configuration using a conveyance belt as in this example, a configuration using a conveyance roller or the like may be used. In this example, the liquid ejection heads 3 include four liquid ejection heads 3Y, 3M, 3C, and 3B for ejecting yellow (Y), magenta (M), cyan (C), and black (Bk) inks. is provided. Corresponding inks are supplied to these liquid ejection heads 3 (3Y, 3M, 3C, 3B). Color images are continuously recorded on the sheet 2 by ejecting ink from the liquid ejection head 3 at a fixed position while the sheet 2 is continuously conveyed in the direction of arrow Y.

FIG. 24C is an explanatory diagram of an ink supply system to the liquid ejection head 3. FIG. The ink in the first ink tank 1011 is supplied to the common supply channel 211 (see FIGS. 2 and 3) in the liquid ejection head 3, passes through the pressure chamber 23, and then passes through the common recovery channel 212 (see FIGS. 2 and 3). 3) and is collected into the second ink tank 1012. As a method for generating an ink circulation flow described later in the liquid ejection head 3, for example, there is a method using a water head difference between the first ink tank 1011 and the second ink tank 1012. Alternatively, there is also a method of controlling the pressure inside the first ink tank 1011 and the second ink tank 1012 to create a pressure difference between the first ink tank 1011 and the second ink tank 1012. Furthermore, a pump or the like may be used to generate an ink circulation flow. The configuration of the ink supply system and the method of generating the ink circulation flow are not limited to this example and may be arbitrary. In other words, it is only necessary to configure a differential pressure generating section that generates a pressure difference necessary for circulation of ink through the pressure chamber.

Note that the method described here is an example and does not limit the scope of the present invention. For example, a circulation path may be formed in which the ink collected in the second liquid tank 1012 is supplied to the liquid ejection head 3 via the first liquid tank 1011 again. Furthermore, the liquid ejection head may have a configuration including only the liquid tank 1011 and include a circulation path in which ink returns from the liquid tank 1011 to the liquid tank 1011 via the liquid ejection head, and is then supplied to the liquid ejection head 3.

(Liquid discharge unit)
25 and 26 are exploded perspective views showing the liquid ejection unit 300. The liquid ejection unit 300 of this embodiment includes the ejection port forming member 12, the first flow path layer 221, the second flow path layer 222, the third flow path layer 223, and the fourth flow path, as shown in FIGS. 25 and 26. It has a six-layered channel configuration consisting of a layer 224, a fifth channel layer 225, and a sixth channel layer 226. The recording element substrate 10 includes a recording element 15, an ejection port forming member 12, and a channel structure (a first channel layer 221 and a second channel layer 222), which will be described later. The recording element substrate 10 includes a substrate including a recording element 15 and an ejection port forming member 12 including an ejection port. Here, the substrate provided with the recording element 15 is made of a Si substrate, and a flow path for supplying the recording element 15 is formed. This flow path includes a liquid supply path 18 and a liquid recovery path 19 that extend along the arrangement direction of the discharge ports 13. Furthermore, this channel communicates with the liquid supply channel 18 and has a plurality of supply ports 17a arranged along the liquid supply channel 18, and a plurality of supply ports 17a which communicate with the liquid recovery channel 19 and are arranged along the liquid recovery channel 19. recovery port 17b.

In the present invention, the substrate provided with the recording element 15 may be a single layer or a multilayer. In the case of a single layer as shown in FIG. 12, a liquid supply path 18, a liquid recovery path 19, a plurality of supply ports 17a, and a plurality of recovery ports 17b are formed in one Si substrate 11, respectively. In the case of a two-layer stacked first and second Si substrate as shown in FIG. 28, a plurality of supply ports 17a and a plurality of recovery ports 17b are formed in the first Si substrate 11, and A liquid supply path 18 and a liquid recovery path 19 are formed in the substrate 115 . A lid member 20 having a plurality of openings 21 is provided on the back side of the Si substrate, regardless of whether the Si substrate is a single layer or a multilayer. The opening 20 includes a supply opening 20 for supplying liquid to the liquid supply path 18 and a recovery opening 20 for recovering liquid from the liquid recovery path 19. A plurality of openings 20 are arranged along the liquid supply path 18 and the liquid recovery path 19. The present invention is not limited to such an example, and for example, the first channel layer 221 may be formed using a first Si substrate, and the second channel layer 222 may be formed using a second Si substrate. Further, at least one opening 20 may be provided for the liquid supply path 18 and the liquid recovery path 19.

As the recording element 15, an electrothermal transducer (heater), a piezoelectric element, or the like can be used. When a heater is used, the heat generated by the heater causes the ink in the pressure chamber 23 to bubble, and the bubbling energy is used to eject the ink from the ejection port 13.

FIG. 27 is a diagram showing the discharge port 13 of the discharge port forming member 12 superimposed on a partially enlarged view of the first channel layer 221. As shown in FIG. As shown in FIG. 27, a plurality of discharge ports 13 are arranged at high density to form a discharge port row 14. In this example, four ejection port arrays 14 are formed in one liquid ejection unit 300.

FIG. 28 is a sectional view showing the liquid supply path 18 and liquid recovery path 19 of the second channel layer 222, and FIG. 29 is a perspective view thereof. As shown in FIG. 28, the liquid supply path 18 of the second flow path layer 222 is connected to one side (left side in FIG. 28) of each pressure chamber 23 via an individual supply port 17a corresponding to each pressure chamber 23. It is communicated. Similarly, the liquid recovery path 19 of the second channel layer 222 is communicated from the pressure chamber 23 to the other side (right side in FIG. 28) of each pressure chamber 23 via the individual recovery port 17b. The liquid supply path 18 communicates with a liquid supply opening 2133 formed in the third channel layer 223, which is a lid member, and ink is supplied from the liquid supply opening 2133. Similarly, the liquid recovery path 19 communicates with a liquid recovery opening 2143 formed in the third channel layer 223. A plurality of liquid recovery ports 2143 are arranged in the ejection port array direction (first direction) in the ejection port row 14, and form a liquid supply opening 2133 row. Similarly, a plurality of liquid recovery openings 2143 are arranged along the same first direction as the liquid supply openings 2133, forming a liquid recovery opening 2143. In the third channel layer 223, 2133 rows of liquid supply openings and 2143 rows of liquid recovery openings are arranged alternately.

A common supply channel 2134 and a common recovery channel 2144 are formed in the fourth channel layer 224, and an individual supply port 2135 and an individual recovery port 2145 are formed in the fifth channel layer 225. A common supply channel 211 and a common recovery channel 212 are formed in the sixth channel layer 226 .

The liquid supply channel 18 communicates with the plurality of supply ports 17a on one side (the first channel layer 221 side) of the second channel layer 222 in the thickness direction, and on the other side (the third channel layer 223 side). It communicates with a plurality of liquid supply openings 2133. Similarly, the liquid recovery path 19 communicates with the plurality of recovery ports 17b on one side in the thickness direction of the second channel layer 222, and communicates with the plurality of liquid recovery openings 2143 on the other side. The common supply path 2134 communicates with the plurality of liquid supply openings 2133 on one side in the thickness direction of the fourth channel layer 224, and communicates with the plurality of second supply ports 2135 on the other side. Similarly, the common recovery path 2144 communicates with the liquid recovery opening 2143 on one side in the thickness direction of the fourth channel layer 224, and communicates with the individual recovery port 2145 on the other side. Further, the common supply channel 211 of the sixth channel layer 226 communicates with a plurality of individual supply ports 2135, and the common recovery channel 212 communicates with a plurality of individual recovery ports 2145.

The arrangement density of the plurality of individual supply ports 2135 and the arrangement density of the plurality of individual recovery ports 2145 are lower than the arrangement density of the plurality of liquid supply openings 2133 and the arrangement density of the plurality of liquid recovery openings 2143. Further, the arrangement density of the plurality of liquid supply openings 2133 and the arrangement density of the plurality of liquid recovery openings 2143 are lower than the arrangement density of the plurality of supply ports 17a and the arrangement density of the plurality of recovery ports 17b. The liquid supply path 18 and the liquid recovery path 19 are each formed in parallel along the first direction, and the common supply path 2134 and the common recovery path 2144 are each formed in parallel along the second direction. has been done. The common supply channel 211 and the common recovery channel 212 are formed in parallel along the first direction.

The liquid ejection unit 300 of this example has a plurality of channel layers, and is configured by stacking the plurality of channel layers. The formation density of channels in those channel layers is as follows: sixth channel layer 226, fifth channel layer 225, fifth channel layer 225, fourth channel layer 224, third channel layer 223, second channel layer The height increases in the order of the channel layer 222 and the first channel layer 221. This makes it possible to configure the liquid ejection unit 300 that includes a plurality of ejection port arrays 14 at high density while suppressing the increase in size of the recording element substrate 10 and each flow path member. Note that these six channel layers may be formed in separate members.

Further, both the first channel layer 221 and the second channel layer 222 are formed on the substrate 11 to form the recording element substrate 10, the third channel layer 223 is formed on the lid member 20, and the fourth channel layer 222 is formed on the substrate 11. 224 is formed on the support member 30. Then, another part of the fourth channel layer 224 is formed in the first channel member 50 (see FIG. 23), and a part of the fifth channel layer 225 and the sixth channel layer 226 are formed in the second channel member 50 (see FIG. 23). It is also possible to adopt a configuration in which it is formed on the member 60 (see FIG. 23) and the other part of the sixth flow path layer 226 is formed on the third flow path member.

Further, both the first channel layer 221 and the second channel layer 222 are formed on the substrate 11 to form the recording element substrate 10, and the third channel layer 223 is formed on the lid member 20. Then, a part of the fourth channel layer 224 is formed on the support member 30, another part of the fourth channel layer 224 and the fifth channel layer 225 are formed on the first channel member 50, and a part of the fourth channel layer 224 is formed on the first channel member 50. A configuration in which the channel layer 226 is formed on the second channel member 60 may also be adopted. In this way, the relationship between the channel layer and the members does not limit the present invention. Further, the configuration of the individual supply path 214a, the individual recovery path 214b, the individual supply port 215a, and the individual recovery port 215b is not limited to this configuration.

The ink supplied from the outside passes from the common supply channel 211 communicating with the ink inflow opening, through the individual supply port 2135, the common supply channel 2134, the liquid supply opening 2133, the liquid supply channel 18, and the supply port 17a in order. It is guided to the pressure chamber 23. The ink in the pressure chamber 23 sequentially passes through the recovery port 17b, the liquid recovery path 19, the liquid recovery opening 2143, the common recovery path 2144, the individual recovery port 2145, and the common recovery channel 212, and then flows out to the common recovery channel 212. It flows out from the opening. By circulating the ink inside the pressure chamber 23 with the outside, the thickened ink and air bubbles that tend to stay inside the pressure chamber 23 flow out, reducing the speed of ink ejection from the ejection port 13, and reducing the ink ejection speed. It is possible to suppress changes in the concentration of the coloring material inside. Hereinafter, such a forced flow of ink will be referred to as an "ink circulating flow."

In this example, the supply port 17a and the recovery port 17b are arranged to face each other with the discharge port 13 in between, as shown in FIGS. 27, 28, and 29. By configuring the pressure chamber 23 to be sandwiched between the supply port 17a and the recovery port 17b in this way, an ink circulation flow passing through the pressure chamber 23 is efficiently generated, and the ink ejection speed is reduced and the color of the ink is reduced. Changes in material concentration can be suppressed more efficiently. Further, the supply port 17a and the recovery port 17b are divided into a plurality of parts in the first direction in which the discharge port row 14 extends, so as to correspond to each of the plurality of pressure chambers 23. In this way, by forming the supply port 17a and the collection port 17b in a plurality of parts, there is a space between adjacent supply ports 17a and between adjacent collection ports 17b for driving the recording element 15. It becomes possible to deploy electrical wiring. Therefore, there is no need to provide wiring extending in the first direction between the supply port 17a and the discharge port 13 and between the collection port 17b and the discharge port 13, and the space between them can be formed smaller. becomes possible. The number relationship between the supply ports 17a and the discharge ports 13 may be 1:1, 1:2, or 1:5, and the number of pressure chambers 23 with which the supply ports 17a communicate may be different from the supply port 17a in this example. The number of ports 17a and discharge ports 13 is not limited to a one-to-one relationship.

In this example, in order to generate an ink circulation flow through the pressure chamber 23 and the ejection port 13, flow paths are formed as follows. The liquid supply path 18 extends in the first direction and communicates with a plurality of supply ports 17a, and further communicates with the pressure chamber 23 via each supply port 17a. Similarly, the liquid recovery path 19 extends in the first direction and communicates with a plurality of recovery ports 17b, and further communicates with the pressure chamber 23 via each recovery port 17b.

It is preferable that the second channel layer 222 and the first channel layer 221 in which the liquid supply channel 18 and the liquid recovery channel 19 are formed are made of the same material. In this example, a first channel layer 221 and a second channel layer 222 are formed on the substrate 11 made of a silicon (Si) substrate. Further, the substrate 11 on which the first channel layer 221 made of a silicon substrate is formed and the second substrate 115 on which the second channel layer 222 also made of a silicon substrate is formed are stacked and bonded, and the second substrate 115 is laminated and bonded. A liquid supply path 18 and a liquid recovery path 19 are formed in the two-channel layer 222 . More preferably, the substrate 11 and the second substrate 115 are bonded by a method that does not use an adhesive, for example, by surface activated bonding or fusion bonding. The reason for this is that when the substrate 11 and the second substrate 115 are bonded so that the ejection ports formed in a high density correspond to the ink channels formed in a high density, the influence of the adhesive extruding is reduced. This is to be done. Through such surface activation bonding or fusion bonding, the silicon substrate 11 and the second substrate 115 are integrated, and the supply port 17a, the recovery port 17b, the liquid supply path 18, and the liquid A recovery path 19 is formed.

In this way, in the first channel layer 221 and the second channel layer 222, a series of ink channels consisting of the supply port 17a, the recovery port 17b, the liquid supply path 18, and the liquid recovery path 19 are connected to the ejection port array 14. Formed in correspondence. Through such an ink flow path, an ink circulation flow can be generated within the pressure chambers 23 of the first flow path layer 221 and the ejection ports 13 of the ejection port forming member 12.

Further, as shown in FIGS. 28 and 29, the side walls forming the supply port 17a, the recovery port 17b, the liquid supply path 18, and the liquid recovery path 19 are formed on the front and back surfaces of the first channel layer 221 (the upper (lower surface). Here, "substantially orthogonal" includes an inclination such as a tapered shape that occurs when the first channel layer 221 and the second channel layer 222 are processed. The supply port 17a, the recovery port 17b, the liquid supply path 18, and the liquid recovery path 19 are formed, for example, by dry etching. Further, they may be formed by laser processing, or dry etching processing and laser processing may be combined. The depth direction (vertical direction in FIG. 28) of the supply port 17a, the recovery port 17b, the liquid supply path 18, and the liquid recovery path 19 is substantially perpendicular to the surface of the first channel layer 221. As a result, these ink channels are efficiently formed in a high density, and an ink circulation flow is more efficiently generated in the pressure chambers 23 and the ejection ports 13 that are formed in a high density in the first channel layer 221. be able to.

(Production method and shape of lid member)
FIG. 30 is a flowchart showing an example of the manufacturing process of the liquid ejection head of this embodiment. In the ejection port forming step 2000, ejection ports are formed on the printing element substrate 10 on which the printing element 15, necessary circuits, etc. are formed. In the back surface supply path forming step 2001, a liquid supply path 18 and a liquid recovery path 19 are formed on the back surface of the recording element substrate 10. Further, in the lid member forming step 2002, a lid member (third channel layer 223) is formed on the back surface of the recording element substrate 10 so as to cover the back surface supply path. In the present invention, after forming the liquid supply path 18 and the liquid recovery path 19 on the back side of the Si substrate in the wafer state, the lid member 20 (223) is provided on the back side of the Si substrate in the wafer state. In this state, a plurality of openings 21 (2133, 2143) smaller than the liquid supply path 18 and the liquid recovery path 19 are formed by patterning. Thereafter, in a cutting step 2003, the outer shape of the recording element substrate 10 is processed from a wafer state to a chip form. Further, in a bonding step 2004, the recording element substrate 10 is bonded to the support member 30 and the first channel member 50. In the arrangement step 2005, a liquid ejection head is manufactured by arranging the bonded members at predetermined positions. Although the method for manufacturing a liquid ejection head having a supply path for supplying liquid to a pressure chamber has been described above, a liquid ejection head having a liquid recovery path 19 for recovering liquid from a pressure chamber as shown in FIG. Applicable. A recording element substrate having a liquid supply path 18 and a liquid recovery path 19 is prepared on the back surface of the recording element substrate, and the liquid supply path 18 and the liquid recovery path 19 formed on the back surface of the recording element substrate are covered. , a film-like lid member is provided on the back surface of the recording element substrate. Thereafter, a plurality of liquid supply openings 2133 communicating with the liquid supply path 18 and smaller than the liquid supply path, and a plurality of liquid recovery openings 2143 communicating with the liquid recovery path 19 and smaller than the liquid recovery path are then formed in the lid member. Thereafter, a plurality of recording element substrates each having a lid member are cut from the wafer, and each recording element substrate is bonded to a support member, thereby producing a liquid ejection head in which a plurality of recording element substrates are arranged.

As described above, in the present invention, the liquid supply path 18 and the liquid recovery path 19 are first formed in the wafer state, and the lid member 20 is provided to cover the liquid supply path 18 and the liquid recovery path 19. After that, a liquid supply opening 2133 communicating with the liquid supply path 18 and a liquid recovery opening 2143 communicating with the liquid recovery path 19 are formed. This makes it possible to form openings (liquid supply opening 2133, liquid recovery opening 2143) with higher density and smaller opening dimensions than the liquid supply path 18 and liquid recovery path 19 with high accuracy. The method for manufacturing the recording element substrate will be described in detail below.

FIG. 31 is a diagram showing the recording element substrate in a state where the lid member 517 is provided, and FIGS. 32 and 33 are cross-sectional views taken along XXXII-XXXII in FIG. 31. Note that the manufacturing process of the recording element substrate will be described below, and in order to distinguish the manufacturing process from each member of the finished product, the reference numerals of the members of the finished product and the reference numerals of the members in the manufacturing process will be changed. Although FIG. 32 shows a partial recording element substrate, individual recording element substrates are manufactured by manufacturing multiple recording element substrates on a wafer at once, and finally cutting them into small pieces. .

First, a pattern 521 serving as a mold for a flow path is provided using a positive photosensitive resin on the front side of a silicon substrate 511 on which recording elements, necessary circuits, etc. are formed. First, a photosensitive resin is provided on the substrate 511 by a spin coating method, a spray coating method, a method of laminating a film, etc., and then a pattern is formed in the shape of the ink flow path using a photolithography method, etc. to form a flow path. A member can be formed. As the positive type photosensitive resin, for example, a polymer main chain decomposition type photosensitive resin containing polymethyl isopropenyl ketone or methacrylic acid ester as a main component is used. The positive photosensitive resin layer can be formed into a desired pattern by exposing the material to light at an optimal exposure wavelength. Next, a discharge port forming member 522 is formed on the front surface side of the substrate 511 using a negative photosensitive resin layer (FIG. 32(a)). Examples of negative photosensitive resins include negative photosensitive resins that utilize radical polymerization reactions and negative photosensitive resins that utilize cationic polymerization reactions. Moreover, one type of negative photosensitive resin may be used alone, or two or more types may be used in combination. Furthermore, additives and the like can be added as appropriate. In addition, as negative photosensitive resins, commercially available "SU-8 series" and "KMPR-1000" (product name) manufactured by Nippon Kayaku Co., Ltd., "TMMR S2000" and "TMMF S2000" (product name) manufactured by Tokyo Ohka Kogyo Co., Ltd. name) etc. can be used.

Further, the method of coating the negative photosensitive resin composition on the mold pattern of the channel is not particularly limited, and for example, a spin coating method, a laminating method, a spray coating method, etc. may be selected as appropriate. After that, an ejection port is formed using a photolithography method or the like.

In addition to the discharge port forming step using a positive photosensitive resin, the discharge port forming member 522 may be formed by laminating a plurality of layers of negative photosensitive resin and using a photolithography method.

Next, using photolithography technology and Si deep etching technology, a common liquid chamber 513 for ink supply (corresponding to the liquid supply path 18 and liquid recovery path 19) and an ink supply port 516 are formed from the back side (FIG. 32(b) )). Thereafter, a resin film serving as a lid member is provided on the surface of the substrate 511 on the side where the common liquid chamber 513 is formed. If the lid member 517 is bonded with an adhesive, the adhesive may protrude into the common liquid chamber 513 and adversely affect the actual shape of the flow path, so it is preferable to bond the lid member 517 without adhesive.

When using a non-photosensitive thermosetting resin, the lid member 517 is formed by laminating the non-photosensitive resin coated on the base film 518 (FIG. 32(c)), and then attaching the base film 518 to the base film 518 (FIG. 32(c)). The film 518 is peeled off (FIG. 32(d)). Thereafter, after curing, the flow path mold 521 is removed (FIG. 32(e)), and openings (corresponding to the supply opening 2133 and the recovery opening 2143) are formed by laser processing (FIG. 32(f)).

Next, a method of forming a lid member using a photolithography method will be described using FIG. 33. The lid member 517 can also be formed by a photolithography method or the like, and damage to the substrate side due to ablation during laser processing can be avoided and higher positional accuracy can be achieved. The steps up to the formation of the common liquid chamber 513 and the ink supply port 516 on the back side are the same as those in FIG. It is transferred onto the surface of the substrate 511 on which the liquid chamber 513 is formed (FIG. 33(a)). Examples of the material for the photosensitive resin layer include negative photosensitive resins using radical polymerization reactions and negative photosensitive resins using cationic polymerization reactions. Negative-tone photosensitive resins that utilize radical polymerization reactions use radicals generated from the photopolymerization initiator contained in the photosensitive resin composition to react with radically polymerizable monomers and prepolymers contained in the photosensitive resin composition. It hardens as polymerization and crosslinking between molecules progresses. Examples of the photopolymerization initiator include benzoins, benzophenones, thioxanthones, anthraquinones, acylphosphine oxides, titanocenes, acridines, and the like. Suitable monomers capable of radical polymerization include monomers and prepolymers having acryloyl groups, methacryloyl groups, acrylamide groups, maleic acid diesters, allyl groups, but are not limited thereto. Negative-tone photosensitive resins that utilize cationic polymerization reactions are produced by cations generated from the photocationic initiator contained in the photosensitive resin. It hardens as polymerization and crosslinking progress. Examples of the photocationic initiator include aromatic iodonium salts and aromatic sulfonium salts. Suitable monomers and prepolymers capable of cationic polymerization include monomers and prepolymers having epoxy groups, vinyl ether groups, and oxetane groups, but are not limited thereto. Moreover, one type of negative photosensitive resin may be used alone, or two or more types may be used in combination. Furthermore, additives and the like can be added as appropriate.

In addition, as negative photosensitive resins, commercially available "SU-8 series" and "KMPR-1000" (product name) manufactured by Nippon Kayaku Co., Ltd., "TMMR S2000" and "TMMF S2000" (product name) manufactured by Tokyo Ohka Kogyo Co., Ltd. name) etc. can also be used. Further, the method for forming the negative photosensitive resin on the base film 518 is not particularly limited, and a spin coating method, a slit die coating method, a spray coating method, etc. can be selected as appropriate. Further, the film thickness of the lid member 517 is preferably 2 to 50 μm, although it depends on the dimensions of the opening, the flow rate and viscosity of the ink supplied. If the film thickness of the lid member 517 is less than 2 μm, the common liquid chamber 513 cannot be sufficiently covered, and ink is likely to leak during ink supply. Furthermore, the lid member 517 is likely to be damaged due to the ink supply pressure.

As the base film 518, for example, PET, polyimide, fluorine film, or hydrocarbon film is used. Next, the base film 518 is peeled off (FIG. 33(b)), and exposure light is applied through the mask 532 (FIG. 33(c)). Next, a lid member is formed by post-baking and developing (FIG. 33(d)). Alternatively, in order to maintain the unevenness of the lid member 517, a process may be used in which the negative photosensitive resin is supported by the base film 518, is exposed, post-baked, and cured, and then the base film 518 is peeled off and developed. Next, after removing the channel mold 521, a curing process is performed. As a result, a recording element substrate is manufactured on the wafer (FIG. 33(e)). Further, the step of removing the channel mold 521 may be performed before forming the lid member 517.

In addition, since the liquid supply opening 2133 and the liquid recovery opening 2143 can be formed in the lid member 517 by lithography processing, the shape accuracy of each and the arrangement accuracy of the liquid supply path 18 and the liquid recovery path 19 can be improved. . By using a resin film with a thickness of 50 μm or less, the shape accuracy was able to be ±5 μm or less, and the placement accuracy was also ±5 μm or less. Furthermore, when the film thickness is less than 25 μm, the shape accuracy can be further improved.
Although not clearly shown in FIGS. 32 and 33, a plurality of openings are formed in the lid member 517 for the liquid supply path 18 and the liquid recovery path 19, respectively, as shown in FIG. 11(c).

By processing the lid member 517 in the wafer process, the shape accuracy is better than when machining or molding, so it is possible to form finer holes with a higher density, and furthermore, the lid member 517 can be made thinner. becomes possible. Further, after forming the liquid supply path 18 and the liquid recovery path 19 on the surface of the substrate, a lid member is provided on the surface of the substrate where these are formed, and then a plurality of openings 21 (2133, 2143) are formed in the lid member. establish. This makes it possible to form minute openings 21 (2133, 2143) in the liquid supply path 18 and liquid recovery path 19 with high precision. It is more preferable in terms of accuracy to carry out such processing by applying a photosensitive film as a lid member to the Si substrate in a wafer state and forming an opening in the lid member using photolithography technology.

In this way, by manufacturing the lid member 517 on the element substrate in a wafer state and increasing the shape accuracy of the liquid supply opening 2133 and the liquid recovery opening 2143, the flow path between the liquid supply opening 2133 and the liquid recovery opening 2143 is improved. Variations in resistance can be reduced. In addition, by increasing the shape accuracy and placement accuracy, the liquid supply openings 2133 and the liquid recovery openings 2143 can be made smaller and placed more accurately. It becomes possible to arrange a flow path relative to the channel 19. In other words, it is possible to form flow paths for the discharge port arrays 14 that are arranged at a higher density. In particular, in a liquid ejection head 3 that generates an ink circulation flow as in this embodiment, it is necessary to arrange a liquid supply path 18 and a liquid recovery path 19 for each ejection port array 14. The density is high, and the effect of using the present invention is great. Furthermore, for the liquid supply path 18 and the liquid recovery path 19 formed along the ejection port array, a plurality of openings having a higher density and smaller opening size than the liquid supply path 18 and the liquid recovery path 19 are formed with high precision. becomes possible.

FIG. 34 is a schematic diagram of the liquid ejection head with the lid member 20 attached to the recording element substrate 10, viewed from the lid member 20 side, and shows the liquid supply opening 2133 formed in the lid member 20 and the recording element substrate. 10 is a diagram showing the arrangement relationship with a liquid supply path 18 formed in 10. FIG. FIG. 34A shows an example in which the width of the liquid supply opening 2133 is larger than the width of the liquid supply path 18. When the shape accuracy is ±5 μm or less and the placement accuracy is ±5 μm or less, the width of the liquid supply opening 2133 is made larger on both sides by 10 μm than the width of the liquid supply path 18, even when the respective precisions vary. The positional relationship shown in (a) remains unchanged. Considering other factors that may cause variations in accuracy, it is preferable to make the width of the liquid supply opening 2133 larger than the width of the liquid supply path 18 by 15 μm on both sides. Since the positional relationship does not change in this way, it is possible to reduce variations in flow path resistance from the liquid supply opening 2133 to the liquid supply path 18. Similarly, as shown in FIG. 34(b), the width of the liquid supply opening 2133 may be made smaller on both sides by 15 μm than the width of the liquid supply path 18. Further, as shown in FIG. 34(c), it may be increased by 15 μm on one side and decreased by 15 μm on the opposite side. In this way, even if the width difference between the liquid supply path 18 and the liquid supply opening 2133 is within 30 μm, it is possible to reduce the variation in flow path resistance. In such a case, for example, when the relationship is as shown in FIG. Even if the beam width between the recovery channel 19 and the recovery channel 19 is reduced to 65 μm, the arrangement relationship remains unchanged. Further, in the case of the relationship shown in FIG. 34(b), even if it is necessary to ensure the width of the liquid supply opening to 150 μm, the arrangement relationship will not change even if the width of the liquid supply channel 18 is reduced to 180 μm.

FIG. 35(a) is a graph showing the relationship between the width of the liquid supply opening 2133 and the pressure loss in the supply channel 18. The effects of the present invention will be explained below. As shown in FIG. 35(a), when the width of the liquid supply opening becomes smaller, the influence on the pressure loss when the width varies becomes larger. In particular, pressure loss becomes large when the width is 200 μm or less. In other words, when the ejection port array is made denser and the liquid supply openings 2133 are made smaller, the influence of the shape accuracy of the liquid supply openings on the variation in flow path resistance increases. As described above, the present invention is particularly effective in a liquid ejection head in which ejection ports are arranged in a high density, and it is possible to reduce variations in flow path resistance, that is, variations in pressure loss that occur in the supply flow path during ejection. This makes it possible to reduce pressure variations at the discharge port meniscus interface. As a result, droplets of more uniform size can be ejected, making it possible to form images with higher definition and higher quality.

Furthermore, in the liquid ejection head 3 that generates an ink circulation flow as in this embodiment, by reducing the variation in flow path resistance, it is possible to further stabilize the differential pressure that generates the ink circulation flow. Variations in the amount of circulation can also be reduced.

FIG. 35(b) is a graph showing an example of the influence of variations in the ink circulation amount, and shows the ink circulation flow rate flowing through the lower part (pressure chamber) of each ejection port and the first shot after a certain period of rest at each ink circulation flow rate. An example of the relationship between droplet ejection speeds is shown. When the circulating flow rate is about 7000 pl/s or more, the first shot can be discharged at a discharge speed of 90% or more of the steady state discharge speed, whereas at a flow rate lower than that, the first discharge speed is 90% or more of the steady state discharge speed. It can be seen that it becomes less than 30%. If the ejection speed decreases in this way, the inkjet will be misaligned when it lands, resulting in deterioration in image quality. Furthermore, in order to increase the circulation flow rate, it is necessary to increase the pressure difference between the first liquid tank 1011 and the second liquid tank 1012 in FIG. system is required, making it difficult to control the pressure at the discharge port. Therefore, the circulation flow rate is preferably made as small as possible without reducing the ejection speed too much, and in the liquid ejection head 3 where the variation in the circulation flow rate is small, it is easy to reduce the circulation flow rate to the extent that the ejection speed does not decrease.

As described above, the present invention can reduce the variation in flow path resistance even in a liquid ejection head in which ejection ports are arranged in a high density. Therefore, it is possible to stabilize the differential pressure that generates the ink circulation flow, and the circulation flow rate can be reduced. It becomes possible to reduce variations. As a result, the ejection characteristics can be made uniform regardless of whether each ejection port is paused or not, and regardless of whether the ejection port is paused or not, and it is possible to form images with higher definition and higher quality.

(Relationship between element board outline and lid member outline)
FIG. 36 is a diagram showing the relationship between the external shapes of the element substrate 2010 and the lid member 517 (20), and FIG. 36(a) shows a state in which the lid member 517 is formed on the element substrate 2010 in a wafer state. The liquid supply opening 2133 and the liquid recovery opening 2143 are omitted. The lid member 517 is divided into units that will eventually become one recording element substrate 10. FIG. 36(b) is an enlarged view of a part of FIG. 36(a). When dividing the element substrate 2010 in a wafer state, it is preferable to divide the element substrate 2010 in an area where the lid member 517 is not provided. By dividing the area in which the lid member 517 is not present, deterioration in shape and peeling of the lid member 517 can be suppressed when dividing the recording element substrate 2010. In other words, by making the external size of the lid member smaller than the external size of the recording element substrate to be cut and divided, it is possible to fabricate the lid member on the element substrate in the wafer state, and the lid member 517 when cut is made smaller. Deterioration of shape and peeling can be suppressed.

For example, various types of etching and dicing are used to divide the element substrate 2010. When dividing by etching, it is necessary to divide the area without the lid member 517. Further, when dividing by blade dicing, if the lid member 517 is present in the area to be divided, the shape of the lid member 517 may deteriorate or come off, and the blade may deteriorate. Furthermore, when dividing by laser dicing, it is necessary to divide the area without the lid member 517 as in the case of etching.

FIG. 36(c) shows one recording element substrate 10 and the lid member 20 after being divided. In order to divide the recording element substrate 2010 in the area without the lid member 20 as shown in FIGS. 36(a) and 36(b), the relationship between the outer shape of the recording element substrate 10 and the outer shape of the lid member 20 is as shown in FIG. 36(c). It is preferable that the lid member 20 is housed inside the outer shape of the recording element substrate 10.

As described above, in this embodiment, the outer shape of the lid member is located inside the outer shape of the recording element substrate, so that cutting after forming the lid member on the wafer-shaped recording element substrate is possible, and the shape of the lid member is not deteriorated. and peeling can be suppressed. That is, when forming a lid member on a wafer-shaped recording element substrate, it is essential to make the outer diameter of the lid member smaller than the outer diameter of the recording element substrate. Note that it can also be suppressed by being at least partially inside without protruding from the outer shape.

(Structure for suppressing variations in ink circulation flow rate and pressure (1))
Furthermore, in this embodiment, in order to suppress variations in the ink circulation flow rate and pressure in each pressure chamber 23, the following structure is provided. That is, as shown in FIGS. 25 and 26, a plurality of liquid supply openings 2133 communicate with one liquid supply path 18, and similarly, a plurality of liquid recovery openings 2143 communicate with one liquid recovery path 19. are doing. These liquid supply openings 2133 and liquid recovery openings 2143 are arranged so that variations in the ink circulation flow rate and pressure in each pressure chamber 23 are within a range that does not significantly affect the ink ejection characteristics. Specifically, in the first direction in which the ejection ports 13 are arranged in the ejection port array 14, the liquid supply openings 2133 and the liquid recovery openings 2143 are arranged alternately. Thereby, the distance between the liquid supply opening 2133 and the liquid recovery opening 2143 in the first direction can be further narrowed. Therefore, even if the widths of the liquid supply path 18 and the liquid recovery path 19 are relatively narrow, variations in the ink circulation flow rate and pressure in each pressure chamber 23 can be suppressed.

(Structure to suppress variations in ink circulation flow rate and pressure (2))
Further, in this embodiment, in order to suppress variations in the ink circulation flow rate and pressure in each pressure chamber 23, the following structure is provided. That is, as shown in FIGS. 25 and 26, the common supply path 2134 extends in a second direction intersecting the arrangement direction of the discharge ports 13, and includes a plurality of liquid supply openings 2133 arranged in the second direction. It communicates with Similarly, the common recovery path 2144 extends in the second direction and communicates with a plurality of liquid recovery openings 2143 arranged in the second direction. Further, the plurality of common supply channels 2134 are collectively communicated with one common supply channel 211 via individual supply ports 2135. Similarly, the plurality of common recovery channels 2144 are collectively communicated with one common recovery channel 212 via individual recovery ports 2145.

In this way, by forming the ink flow path with a six-layer structure, the plurality of liquid supply paths 18 formed at a narrow pitch in accordance with the plurality of ejection port rows 14 arranged in high density can be used to supply a plurality of liquids. Via the opening 2133, they are finally combined into one common supply channel 211. Similarly, the plurality of liquid recovery paths 19 formed at a narrow pitch in accordance with the plurality of discharge port rows 14 arranged in high density are finally formed into one common recovery flow through the plurality of liquid recovery openings 2143. route 212. Therefore, the plurality of ejection port arrays 14 can be arranged at high density without increasing the channel widths of the liquid supply channel 18 and the liquid recovery channel 19. Furthermore, variations in the ink circulation flow rate and pressure can be suppressed in each pressure chamber 23 corresponding to each ejection port 13 of the plurality of ejection port arrays 14 arranged in such a high density manner. In addition, for the ejection ports 13 that are arranged in high density, ink can be supplied from an ink tank (not shown) and ink can flow out to the ink tank while suppressing variations in the ink circulation flow rate and pressure in the pressure chamber 23. can be easily realized. As a result, not only the liquid ejection head and the recording device equipped with the same, but also various liquid ejection heads and the entire system of the liquid ejection device equipped with the same can be configured compactly.

(Structure to suppress variations in ink circulation flow rate and pressure (3))
Further, in order to suppress variations in the ink circulation flow rate and pressure in each pressure chamber 23, it is desirable to provide the following structure. That is, the liquid supply openings 2133 and/or the liquid recovery openings 2143 located at both ends of the ejection port array 14 are made smaller in shape than the liquid supply openings 2133 and/or the liquid recovery openings 2143 located at other than both ends. In other words, the openings of the liquid supply openings 2133 and/or liquid recovery openings 2143 located at both ends of the discharge port array 14 are smaller than the openings of the liquid supply openings 2133 and/or liquid recovery openings 2143 located at both ends of the discharge port array 14. Form. With respect to the liquid supply openings 2133 located at both ends of the ejection port array 14, the ejection ports 13 of the ejection port array 14 are located only on one side. Therefore, the ink flow rate at the liquid supply openings 2133 located at both ends of the ejection port array 14 is smaller than the ink flow rate at the other liquid supply openings 2133. Similarly, with respect to the liquid recovery openings 2143 located at both ends of the ejection port array 14, the ejection ports 13 of the ejection port array 14 are located only on one side. Therefore, the ink flow rate at the liquid recovery openings 2143 located at both ends of the ejection port array 14 is smaller than the ink flow rate at the other liquid recovery openings 2143.

In this way, the shapes of the liquid supply openings 2133 and/or the liquid recovery openings 2143 located at both ends of the ejection port array 14 are made small to increase the flow path resistance. Thereby, the pressure loss occurring at these liquid supply openings 2133 and/or liquid recovery openings 2143 can be brought closer to the pressure losses occurring at other liquid supply openings 2133 and/or liquid recovery openings 2143. Therefore, the flow rate of ink flowing into the pressure chamber 23 through the liquid supply opening 2133 and/or liquid recovery opening 2143 at both ends, and the flow rate of ink flowing into the pressure chamber 23 through the other liquid supply opening 2133 and/or liquid recovery opening 2143. The difference can be made smaller. As a result, variations in the ink circulation flow rate within each pressure chamber 23 can be further suppressed.

(Structure for suppressing variations in ink circulation flow rate and pressure (4))
FIG. 37 is a diagram showing the recording element substrate 10 and the positions of the liquid supply opening and the liquid recovery opening in the recording element substrate 10. The recording element substrate 10 preferably has the following structure in order to suppress variations in the ink circulation flow rate and pressure in each pressure chamber 23. That is, as shown in FIG. 37A, the area a between the end of the ejection port array 14 and the end of the recording element substrate 10 is set to be large. The area a can be used, for example, as a space for arranging pad terminals 16 for transmitting and receiving electrical signals to and from the recording element substrate 10, a drive circuit for the recording elements 15, and the like. Further, it is desirable to utilize such area a to provide a liquid recovery port 2133 as shown in the perspective views of FIGS. 37(b) and 37(c). That is, in the first direction in which the ejection port array 14 extends, the liquid recovery port 2133 is arranged so as to overlap the ejection ports 13 located at the ends of the ejection port array 14 . In these FIGS. 37(b) and 37(c), the left end of the liquid recovery path 19 and the left end of the liquid recovery opening 2143 are at the same position. In addition, in FIG. 37(c), the left end portions of the liquid recovery path 19 and the liquid recovery opening 2143 bulge out to the left more than the recovery port 17b located at the left end.

In FIGS. 37(b) and 37(c), ink passing through the pressure chamber 23 located at the end of the ejection port array 14 first flows from the liquid supply opening 2133 to the liquid supply path 18 and the supply port 17a, as shown by arrow A1. enter. Thereafter, as indicated by arrow A2, the liquid passes through the pressure chamber 23 located at the end of the discharge port array 14, the recovery port 17b, and the liquid recovery path 19, and then flows out from the liquid recovery opening 2143. FIG. 37D shows a comparative example in which the liquid recovery openings 2143 are arranged so as not to overlap the discharge ports 13 located at the ends of the discharge port array 14 in the first direction. In FIG. 37(d), ink passing through the pressure chamber 23 located at the end of the ejection port array 14 first enters the liquid supply path 18 and the supply port 17a through the liquid supply opening 2133, as indicated by arrow A1. Thereafter, the liquid passes through the pressure chamber 23 located at the end of the discharge port array 14 and the recovery port 17b as indicated by arrow A2, passes through the liquid recovery path 19 as indicated by arrow A3, and flows out from the liquid recovery opening 2143.

In FIGS. 37(b) and 37(c), compared to the configuration in FIG. 37(d), the liquid supply opening 2133 located at the end in the first direction passes through the pressure chamber 23 to the liquid recovery opening 2143. The length of the ink flow path from the ink to the outflow can be shortened. In other words, it is possible to reduce the maximum pressure loss occurring in the liquid supply path 18 and the liquid recovery path 19 near the ends of the ejection port array 14, thereby suppressing variations in the ink circulation flow rate within each pressure chamber 23. Note that when the liquid supply opening 2133 instead of the liquid recovery opening 2143 is located at the end in the first direction, the ejection port 13 located at the end of the ejection port row 14 in the first direction The liquid supply opening 2133 may be arranged so as to overlap with the liquid supply opening 2133.

(Temperature distribution suppression structure)
In this embodiment, in order to suppress the temperature distribution within the liquid ejection head 3, the following structure is provided. That is, as shown in FIGS. 25 and 26, liquid recovery openings 2143 are located at both ends of the discharge port array 14. When the ink is forcibly circulated through each pressure chamber 23 as in this example, the heat emitted from the recording element 15 etc. is normally recovered by the ink, so the ink outflow side is The temperature of the ink in the flow path increases. Furthermore, even if sufficient ink circulation flow rate is ensured to suppress the effects of evaporation of water in the ink from the ejection ports 13, when ink is simultaneously ejected from a large number of ejection ports 13, the ink circulation flow rate is larger than the ink circulation flow rate. In some cases, the discharge amount may be larger. In such a case, ink is also supplied into the pressure chamber 23 from the common recovery channel 212. That is, ink is supplied from the common recovery flow path 212 into the pressure chamber 23 through the individual recovery port 2145, the common recovery path 2144, the liquid recovery opening 2143, the liquid recovery path 19, and the recovery port 17b. Therefore, when ink is simultaneously ejected from a large number of ejection ports 13 , high-temperature ink within the liquid recovery opening 2143 may be supplied into the pressure chamber 23 . In such a case, the temperature of the ink near the liquid recovery opening 2143 becomes higher than that near the liquid supply opening 2133, and the ejection ports 13 near the liquid supply opening 2133 and the ejection ports 13 near the liquid recovery opening 2143 There is a possibility that a difference in ink ejection speed may occur between the two. Furthermore, when the liquid supply opening 2133 is located at one end of both ends of the ejection port array 14 and the liquid recovery opening 2143 is located at the other end, the heat distribution in the entire ejection port row 14 is different in the arrangement direction. As a result of the inclination, the width of the heat distribution as a whole of the liquid ejection head becomes large. As a result, there is a possibility that the ink ejection characteristics at each ejection port 13 vary.

In this embodiment, since the liquid recovery openings 2143 are provided at each end of the ejection port array 14, it is possible to suppress the inclination of such heat distribution and to suppress variations in the ink ejection characteristics. Note that the same effect can be obtained when liquid supply openings 2133 are provided at both ends of the ejection port array 14, respectively. However, as in this embodiment, it is desirable to provide liquid recovery openings 2143 at both ends of the ejection port array 14, respectively.

That is, in the printing element substrate 10, as described above, a large area a is set between both ends of the ejection port array 14 and the end of the printing element substrate 10, where the ejection ports 13 are not provided. Heat generated during ink ejection is radiated from a. Therefore, when a large number of ejection ports 13 eject ink, the temperature at both ends of the ejection port array 14 tends to be lower than the other portions. By providing liquid recovery openings 2143 at both ends of the ejection port array 14, high-temperature ink can be supplied to both ends of the ejection port array 14 in such a case. Therefore, the temperature at both ends of the discharge port array 14 can be made higher, and the temperature difference with other parts can be reduced. As a result, the heat distribution width of the entire liquid ejection head can be reduced, and variations in ink ejection characteristics can be suppressed.

In this way, a lid member is produced on the element substrate in the form of a wafer, and then the element substrate is cut to produce a recording element substrate in the form of chips. As a result, it was possible to realize a liquid ejection head and a liquid ejection device that can suppress pressure variations in the pressure chambers.

(Second embodiment)
A second embodiment of the present invention will be described below with reference to the drawings. Note that since the basic configuration of this embodiment is the same as that of the first embodiment, only the characteristic configuration will be described below.

FIGS. 38 and 39 are diagrams showing the liquid ejection unit 300 in this embodiment, and the same parts as those in the above-described embodiment are given the same reference numerals and explanations will be omitted. 38 is an exploded perspective view of the liquid ejection unit 300, and FIG. 39 is an exploded plan view of the liquid ejection unit 300. In this embodiment, at a position on one end side of the discharge port array 14, the liquid supply path 18 and the liquid supply opening 2133 communicate with each other, and the liquid recovery path 19 and the liquid recovery opening 2143 communicate with each other. Similarly, at a position on the other end side of the discharge port array 14, the liquid supply path 18 and the liquid supply opening 2133 communicate with each other, and the liquid recovery path 19 and the liquid recovery opening 2143 communicate with each other. By arranging the liquid supply opening 2133 and the liquid recovery opening 2143 at both ends of the ejection port array 14, the variation in the ink circulation flow rate in the first direction in which the ejection port row 14 extends is reduced more than in the first application example. , and variations in pressure within each pressure chamber 23 can be suppressed. Further, it is sufficient to provide only two common supply paths 2134 and two common recovery paths 2144.

In this manner, in this embodiment, the number of liquid supply openings and liquid recovery openings can be reduced, and the structure of the ink flow path can be simplified.

(Third embodiment)
A third embodiment of the present invention will be described below with reference to the drawings. Note that since the basic configuration of this embodiment is the same as that of the first embodiment, only the characteristic configuration will be described below.

FIGS. 40 to 42 are diagrams showing a liquid ejection unit 600 in this embodiment, and the same parts as those in the above-described embodiment are given the same reference numerals and explanations will be omitted. 40 is an exploded perspective view of the liquid ejection unit 600, and FIG. 41 is an exploded plan view of the liquid ejection unit 600. FIG. 42(a) is a plan view of the recording element substrate 610 in this embodiment, and FIG. 42(b) is a perspective view for explaining the structure of the end portion of the ejection port array 14.

The recording element substrate 610 in this embodiment has a parallelogram outer shape, and is different from the recording element substrate 10 in FIG. The area a between the substrate edge and the edge of the substrate is small (see FIG. 42(a)). In this embodiment, in order to transmit and receive electrical signals between the printing element substrate 610 and the outside, drive circuits such as the connection pad 16 and the printing element 15 are arranged along the length of the printing element substrate 610 as shown in FIG. 42(a). placed on the side. Note that the outer shape is not limited to a parallelogram but may be a rectangle. When a long liquid ejection head (line head) is configured by combining such printing element substrates 610, the printing element substrates 10 are not arranged in a staggered pattern, but are arranged in a manner as shown in FIGS. 23(d) and 23(e). 42(a), they are arranged substantially in one row. In other words, adjacent element substrates are arranged so as to partially overlap each other in both the longitudinal direction and the lateral direction of the liquid ejection head. With this arrangement, the ends of the ejection port arrays 14 on the recording element substrates 10 adjacent to each other can be easily overlapped in the second direction, which is the vertical direction in FIG. 42(a). .

Here, "substantially arranged in one row" refers to the first direction in which the discharge ports 13 extend in the discharge port array 14 as shown in FIG. 42(a), and the direction intersecting the first direction. The recording element substrates 610 adjacent to each other are arranged to partially overlap in both the second direction and the second direction.

In this manner, in this embodiment, the ejection ports 13 are arranged even near the ends of the recording element substrate 610. In such a configuration, as shown in FIGS. 37(b) and 37(c) in the first application example, a liquid supply opening 2133 or a liquid recovery opening is provided at a position overlapping with the end of the ejection port array 14 of the recording element substrate 610. 2143 is difficult to place. Therefore, in this embodiment, as shown in FIG. 42(b), the liquid supply opening 2133 or the liquid recovery opening 2143 is arranged at a position shifted toward the center from the end of the ejection port array 14.

In this embodiment, in order to suppress variations in the ink circulation flow rate and pressure in each pressure chamber 23, and further suppress temperature distribution within the recording element substrate 610, the ejection port array 14 is arranged as shown in FIGS. 40 and 41. Liquid supply openings 2133 are provided near both ends.

When the liquid supply opening 2133 is arranged near the end of the ejection port array 14 as in this embodiment, the difference between the liquid supply path 18 and the liquid recovery path 19 located at the end of the ejection port row 14 The pressure is greater during ink discharge than during ink circulation due to the initial differential pressure. On the other hand, when the liquid recovery port 2133 is arranged at the end of the ejection port array 14 as in the first application example, between the liquid supply path 18 and the liquid recovery path 19 at the end of the ejection port row 14. The differential pressure during ink discharge is smaller than that during ink circulation due to the initial differential pressure. When the differential pressure between the liquid supply path 18 and the liquid recovery path 19 decreases, the ink circulation flow rate decreases, and the influence of water evaporation in the ink from the ejection port 13, that is, the decrease in the ink ejection speed, and the color of the ink. The effect of suppressing changes in material concentration is reduced. Therefore, the larger the differential pressure, the better. By providing the liquid supply openings 2133 near both ends of the ejection port array 14 as in this embodiment, the influence of variations in the ink circulation flow rate can be reduced.

The pressure inside the liquid supply opening 2133 is set higher than the pressure inside the liquid recovery opening 2143 in order to generate an ink circulation flow, and when ink is ejected, the ink is supplied into the pressure chamber 23 through the liquid supply opening 2133. It becomes easier to do. By arranging the liquid supply opening 2133, which facilitates the supply of ink, near the end of the ejection port row 14, when ink is ejected from a large number of ejection ports 13 simultaneously, the liquid supply path 18 and the liquid recovery path The pressure loss occurring at 19 can be reduced.

Furthermore, in this embodiment, as described above, since the area a between the end of the ejection port array 14 and the end of the element substrate is small, the extent to which the heat generated when ink is ejected is radiated from the area a is limited. small. As region a is small, as shown in FIG. 42(b), the portion of the liquid supply path 18 from the liquid supply opening 2133 to the end of the ejection port array 14 becomes long, and similarly, the portion from the liquid recovery opening 2143 to the end of the ejection port array 14 becomes long. The portion of the liquid recovery path 19 up to the end of the discharge port array 14 becomes longer. Therefore, the ink passing through the liquid supply path 18 and liquid recovery path 19 easily receives heat from the recording element substrate 610. Therefore, when ink is simultaneously ejected from a large number of ejection ports 13, the temperature at the end of the ejection port array 14 tends to be higher than the other portions. Further, when ink is ejected, the pressure loss occurring in each ink flow path becomes large, and pressure variations at the ends of the ejection port array 14 become large.

Furthermore, in this embodiment, as described above, the liquid supply openings 2133 are arranged at both ends of the ejection port array 14, respectively. Therefore, a large amount of ink is supplied to the ejection ports 13 near the ends of the ejection port array 14 from the liquid supply openings 2133 arranged in the vicinity. As a result, when ink is simultaneously ejected from a large number of ejection ports 13, the amount of high-temperature ink supplied from the liquid supply opening 2133 is reduced, and temperature rise at the end of the ejection port array 14 can be reduced. .

Specifically, ink supplied from the liquid supply opening 2133 first enters the supply port 17a from the liquid supply path 18, as indicated by arrow B1 in FIG. 42(b). Thereafter, the ink passes through the pressure chamber 23 located at the end of the ejection port array 14 and the recovery port 17b as indicated by arrow B2, and then passes through the liquid recovery path 19 as indicated by arrow A3 to the liquid recovery opening 2143. flows out from.

In this embodiment, by arranging the liquid supply openings 2133 at both ends of the ejection port array 14, variations in the circulating flow rate and pressure of ink can be suppressed, and the temperature distribution within the liquid ejection head can be controlled. can be kept small. Therefore, a decrease in the ink ejection speed due to evaporation of water in the ink from the ejection port 13 and a change in the coloring material concentration of the ink are suppressed, and variations in the ink ejection characteristics are suppressed, resulting in higher definition and higher quality. It becomes possible to record images.

(Arrangement configuration of liquid supply opening and liquid recovery opening)
FIG. 43 is a graph showing the temperature distribution of the recording element substrate 610 when ejecting from all the ejection ports. Next, the temperature distribution of the entire recording element substrate 610 in this embodiment will be explained. The recording element substrate 610 is in a state where the temperature is controlled at 50 degrees. Since the flow rate due to ejection is larger than the flow rate of the ink circulation flow, the direction of the ink flow in the liquid recovery opening 2143 is toward the ejection port. Further, the flow rates of the liquid supply opening 2133 and the liquid recovery opening 2143 tend to be larger for the liquid supply opening 2133. FIG. 43(a) shows the temperature distribution when, as a comparative example, one liquid supply opening 2133 and one liquid recovery opening 2143 are arranged for one ejection port array 14. The ink flowing through the liquid supply path 18 and the liquid recovery path 19 receives heat from the recording element substrate 610, and the temperature at the center becomes high. Further, when comparing the temperatures of the liquid supply opening 2133 and the liquid recovery opening 2143, the temperature of the liquid supply opening 2133 is lower because the flow rate of the liquid supply opening 2133 is larger. Note that even when the liquid recovery opening 2143 does not flow backward, the ink that has once flowed through the recording element substrate 610 and received heat flows through the liquid recovery opening 2143, so the temperature of the liquid supply opening 2133 tends to decrease. FIG. 43(b) shows the temperature distribution when a plurality of liquid supply openings 2133 and a plurality of liquid recovery openings 2143 are arranged alternately for one ejection port row in this embodiment. Since the distance between the liquid supply opening 2133 and the liquid recovery opening 2143 is short, the length of flow through the liquid supply path 18 and the liquid recovery path 19 is shortened, so the temperature rise between them is small, and the temperature rise between them is small. The temperature is like that. Furthermore, since the liquid supply openings 2133 and the liquid recovery openings 2143 are arranged alternately, the maximum length of the liquid flowing through the liquid supply path 18 and the liquid recovery path 19 is shortened, so that the temperature rise is small.

In this way, in this embodiment, a plurality of liquid supply openings 2133 and a plurality of liquid recovery openings 2143 are arranged alternately with respect to one ejection port row, so that FIG. The temperature difference within the recording element substrate 610 can be reduced compared to the above. Therefore, it is possible to suppress variations in ejection characteristics, so that it is possible to form images with higher definition and higher quality. Note that the effects of this embodiment can be obtained if there are at least two or more of either the liquid supply opening 2133 or the liquid recovery opening 2143.

FIG. 44A shows each ejection port row when the liquid supply openings 2133 and liquid recovery openings 2143 for the plurality of ejection port rows 14 are arranged offset from each other in accordance with the parallelogram of the recording element substrate 610. 14 is a graph showing the temperature distribution at No. 14. Although there is a difference in the absolute temperature value of each ejection port row itself depending on the position of the ejection port row, it can be seen that the high temperature position and the low temperature position are shifted in accordance with the shift between the liquid supply opening 2133 and the liquid recovery opening 2143. FIG. 44(b) is a graph obtained by averaging the temperature distribution in FIG. 44(a) in the row direction of the discharge port rows 14. Since the high temperature and low temperature positions in each ejection port array are different from each other, when averaged, the temperature difference within the recording element substrate 610 is greater than the temperature difference when considering all the ejection port rows in FIG. 44(a). is also smaller. Therefore, if the scanning direction of the printed material (the relative scanning direction of the liquid ejection head and the printed material) is perpendicular to the column direction of the ejection port array 14, then the influence of variations in ejection characteristics due to temperature differences on the printed material can be averaged out. can be converted into

In this way, by arranging the liquid supply opening 2133 and the liquid recovery opening 2143 so as to be shifted from each other, the temperature difference caused by the arrangement of the liquid supply opening 2133 and the liquid recovery opening 2143 can be averaged out. Therefore, it is possible to suppress variations in ejection characteristics, so that it is possible to form images with higher definition and higher quality.

(Example of modified shapes of liquid supply opening and liquid recovery opening)
FIG. 45 is a diagram showing a modification regarding the shape of the liquid supply opening 2133 or the liquid supply opening 2143. FIG. 45(a) is a view of the lid member 620 and the recording element substrate 610 viewed from the side opposite to the ejection ports. FIG. 45(b) is a diagram showing details of the liquid supply opening 2133 in FIG. 45(a), and also shows the liquid supply path 18 on the recording element substrate 10. FIG. 45(c) shows a state in which the support member 30 having the fourth channel layer 224 or the first channel member 50 is joined to the lid member 620. As shown in FIG. 45(b), the liquid supply opening 2133 has a parallelogram shape matching the outer shape of the recording element substrate 610. By forming the parallelogram in this way, the width W5 of the bonding surface between the lid member 620 and the fourth channel layer 224 in FIG. It can be made larger. In other words, in consideration of the protrusion of the adhesive and the like when bonding the lid member 620 and the fourth channel layer 224, it is desirable to set a large minimum distance W6 between the outer shapes of the liquid supply opening 2133 and the common supply channel 2134. By forming the liquid supply opening 2133 into a parallelogram, the cross-sectional area, width W5, and interval W6 of the liquid supply opening 2133 can be made larger. By performing lithography processing, it is possible to process fine and complicated shapes such as this shape, and the cross-sectional area of the liquid supply opening 2133 and the liquid recovery opening 2143, the lid member 620, the support member 30, and the first flow path member can be processed. This makes it easier to enlarge the joint surface with 50.

(Linear expansion coefficient of lid member)
In a liquid ejection head in which a plurality of recording element substrates are arranged, the lid member 620 is separated for each recording element substrate, so that deterioration in the accuracy of arrangement of the element recording element substrates can be suppressed. In other words, in a liquid ejection head such as that shown in FIG. 23(d) or FIG. 24(e), a lid member integrated in the longitudinal direction is used for a plurality of recording element substrates as in Patent Document 1. In this case, the linear expansion coefficient of the lid member may be affected by temperature changes, and the accuracy of placement of the recording element substrate may deteriorate. On the other hand, since the lid member 620 is separated for each recording element substrate as in this embodiment, the deterioration of the placement accuracy of the recording element substrate due to temperature change in the longitudinal direction of the liquid ejection head can be avoided due to the line of the lid member. It largely depends on the linear expansion coefficient of the member that supports the recording element substrate, rather than the expansion coefficient. When a resin film is used for the lid member 620, the coefficient of linear expansion is generally about 30 ppm. On the other hand, for example, when alumina is used for the member supporting the plurality of recording element substrates 610, the amount can be about 7 ppm, and when a resin material filled with a filler that reduces the coefficient of linear expansion is used, it can be about 20 ppm. That is, by dividing the lid member 620 for each printing element substrate and reducing the linear expansion coefficient of the member that integrally supports the plurality of printing element substrates 610, it is possible to improve the accuracy of arrangement of the printing element substrates.

(Gap between adjacent boards)
In this embodiment, by providing a separate lid member 620 for each printing element substrate, it is possible to reduce the deviation width of the ejection port array at the joint between the printing element substrates 610. In other words, when forming a lid member that spans adjacent recording element substrates, adhesive may be required to bond the recording element substrates to the lid member, and in such a case, the adhesive may spread. It is necessary to widen the distance between adjacent recording element substrates in consideration of creeping up. In contrast, in this embodiment, by adopting configurations (1) and (2) of the gap between adjacent substrates in the fourth embodiment described later, the adhesive can It becomes possible to bring the recording element substrates closer to each other. As a result, it is possible to reduce the deviation width of the printing element substrates from each other in the scanning direction of the printed matter at the joint between the printing element substrates, and to reduce the deviation width of the ejection port array. Therefore, defects such as unevenness in images at seams are reduced, and high-quality images can be formed.

(Fourth embodiment)
A fourth embodiment of the present invention will be described below with reference to the drawings. Note that since the basic configuration of this embodiment is the same as that of the first embodiment, only the characteristic configuration will be described below.

(Configuration of gap between adjacent boards (1))
46 and 47 are diagrams showing an example of the structure of the gap between adjacent recording element substrates in this embodiment. FIG. 46 is a schematic diagram of the liquid ejection head of this embodiment, where FIG. 46(a) is a perspective view and FIG. 46(b) is an exploded perspective view. 47 is a schematic diagram between adjacent element substrates in this embodiment, FIG. 47(a) is a top view, and FIG. 47(b) is a cross-sectional view taken along XLVIIb-XLVIIb in FIG. 47(a). be.

In this embodiment, the lid member 20 is disposed on the back surface of the recording element substrate 10, the liquid supply path 18 for supplying liquid to the ejection ports 13 is located on the rear surface of the recording element substrate 10, and the lid member 20 is arranged on the back surface of the recording element substrate 10. It serves as a lid for the supply channel 18. Furthermore, a liquid supply opening 2133 for supplying liquid to the liquid supply path 18 is provided in the lid member 20 and communicates with a supply path provided in the support member 50.

In this embodiment, by arranging the ejection ports 13 also in the area of the recording element substrate 50 that protrudes above the groove 55 of the first flow path member 50, which is a support member, the ejection port array at the joint of the recording element substrates is arranged. It is configured to reduce the deviation width. As shown in FIG. 47(b), in the gap where the recording element substrates 10 are adjacent to each other, the liquid supply path 18 is also arranged in the recording element substrate 10 at a portion protruding above the groove of the first flow path member 50. The lid member 20 serves as a lid for the liquid supply path 18. In the adjacent gap, the joint between the lid member 20 and the support member 50 enters inside from the outer edge of the recording element substrate. In this way, by covering the liquid supply path 18 protruding above the groove 55 with the lid member 20, the first flow path is It is also possible to supply liquid to the discharge port 13 at a location protruding outward from the end of the member 50. That is, first, by making the width of the groove 55 provided on the first flow path member (the length in the longitudinal direction of the first flow path member 50) larger than the width of the gap between the recording element substrates, the adjacent recording The distance between the element substrates can be reduced. Furthermore, by covering the liquid supply path 18 protruding above the groove 55 of the first flow path member 50 with the lid member 20, the ejection port 13 can be arranged up to the end of the recording element substrate 10. , it is possible to further reduce the deviation width of the ejection port array at the joint between the recording element substrates. For example, a case will be compared in which the distance between recording element substrates is reduced from 0.2 mm to 0.03 mm by using this embodiment. If the ejection ports at the end of the ejection port array can be arranged at a position 0.05 mm from the end of the recording element and the angle of the oblique side of the chip is 45 degrees, the deviation width of the ejection port array will vary from about 0.42 mm to about 0.05 mm. The deviation width of the discharge port array was significantly reduced by the present invention.

In this way, even when an adhesive is used to bond the recording element substrate 10 and the first flow path member 50, the width of the deviation between the recording element substrates in the scanning direction of the printed matter at the joint between the recording element substrates can be reduced. It is possible to reduce the deviation width of the ejection port array. As a result, defects such as unevenness in images at seams are reduced, and high-quality images can be formed.

Further, in this embodiment, it is preferable that the outer shape of the lid member 20 is smaller than the outer shape of the recording element substrate 10. In other words, it is possible to bring adjacent printing element substrates closer to each other at the joint, regardless of the machining accuracy of the lid member 20, and the deviation width between the printing element substrates in the scanning direction of the printed matter at the joint of the printing element substrates can be reduced. It is possible to reduce the deviation width of the ejection port array. As a result, defects such as unevenness in images at seams are reduced, and high-quality images can be formed.

(Configuration of gap between adjacent boards (2))
48 to 49 are diagrams showing an example of the structure of the gap between adjacent substrates in this embodiment. FIG. 48 is a schematic diagram of the liquid ejection head of this configuration example, FIG. 48(a) is a perspective view, and FIG. 48(b) is an exploded perspective view. FIG. 49 is a schematic diagram between adjacent element substrates of this embodiment, where FIG. 49(a) is a top view and FIG. 49(b) is a cross-sectional view taken along XLIXb-XLIXb in FIG. 49(a).

Here, a case where the distance between adjacent recording element substrates is reduced from 0.2 mm to 0.02 mm will be compared. If the ejection ports at the end of the ejection port array can be arranged at a position 0.05 mm from the end of the recording element and the angle of the oblique side of the chip is 45 degrees, the deviation width of the ejection port array will vary from about 0.42 mm to about 0.05 mm. The deviation width of the discharge port array was able to be significantly reduced by the present invention.
In this way, the present invention can reduce the deviation width between the elements in the scanning direction of the printed matter at the joint of the printing element substrate 10, and reduce the deviation width of the ejection port array. As a result, defects such as unevenness in images at seams are reduced, and high-quality images can be formed.

Further, similarly to the above-described configuration example, it is possible to suppress the adhesive from creeping up onto the ejection port surface in the adjacent portion of the recording element substrate. When an adhesive is used to bond the lid member 20 and the first flow path member 50, the ends of the lid member 20 and the recording element substrate 10 are placed outward from the ends of the first flow path member 50 as in this embodiment. Due to the protrusion, the protruding adhesive accumulates on the back surface of the protruding lid member 20. Therefore, compared to a configuration in which the adhesive does not protrude outward, it is possible to suppress the adhesive from creeping up to the discharge port surface in the adjacent portion.

Note that although the structure of the gap between adjacent substrates has been described using the parallelogram-shaped recording element substrate 10 as in this embodiment, it is not limited to the parallelogram. For example, the present invention can also be applied to a liquid ejection head in which a plurality of rectangular recording element substrates 10 are arranged side by side.

(Fifth embodiment)
A fifth embodiment of the present invention will be described below with reference to the drawings. Note that since the basic configuration of this embodiment is the same as that of the first embodiment, only the characteristic configuration will be described below. This embodiment also includes the third flow channel layer 223 as a lid member, similarly to each of the embodiments described above.

FIGS. 50 and 51 are diagrams showing a liquid ejection unit 700 in this embodiment, and the same parts as those in the above-described embodiment are given the same reference numerals and explanations will be omitted. 50 is an exploded perspective view of the liquid ejection unit 700, and FIG. 51 is an exploded plan view of the liquid ejection unit 700.

In this embodiment, as shown in FIG. 50, three liquid supply paths 18 (18A, 18B, 18C) and two liquid recovery paths 19 are provided for four ejection port arrays 14 (14A, 14B, 14C, 14D). (19A, 19B) are arranged. As shown in FIG. 51, a common recovery port 17b is arranged between the discharge port arrays 14A and 14B, and the recovery port 17b communicates with the liquid recovery path 19A. Further, a common supply port 17a is arranged between the discharge port arrays 14B and 14C, and the supply port 17a is communicated with the liquid supply path 18B. Further, a common recovery port 17b is arranged between the discharge port arrays 14C and 14D, and the recovery port 17b communicates with the liquid recovery path 19B. The supply ports 17a of the ejection port array 14A are communicated with the liquid supply path 18A, and the supply ports 17a of the ejection port array 14D are communicated with the liquid supply path 18C.

In this way, one liquid supply path 18B communicates with the pressure chambers 23 of the two ejection port rows 14B and 14C via the common supply port 17a for these ejection port rows 14B and 14C. Further, one liquid recovery path 19A communicates with the pressure chambers 23 of the two discharge port arrays 14A and 14B via a common recovery port 17b for the two discharge port arrays 14A and 14B. Similarly, one liquid recovery path 19B communicates with the pressure chambers 23 of the two ejection port rows 14C and 14D via a common recovery port 17b for these ejection port rows 14C and 14D.

According to this embodiment, in addition to the effects of the embodiment described above, the following effects can be achieved. That is, by sharing the liquid supply path 18 and the liquid recovery path 19 between two adjacent ejection port arrays, it is possible to reduce the number of partitions between the ink flow paths and the number of ink flow paths. Therefore, it is possible to narrow the distance between the ejection port arrays 14 and to increase the width of the ink flow path. As a result, variations in the ink circulation flow rate and pressure in each pressure chamber 23 are further suppressed, and the ejection port arrays 14 are arranged more densely than in the above-described embodiment, thereby improving the liquid ejection unit 700 and the liquid ejection head. The size can be reduced. Furthermore, when the arrangement density of the ejection port arrays 14 is the same, it is possible to further suppress variations in the ink circulation flow rate and pressure in each pressure chamber 23, and to reduce the number of liquid supply openings 2133 and liquid recovery openings 2143. can. Therefore, the ink flow path structure in the liquid ejection unit 700 can be simplified.

(Sixth embodiment)
A sixth embodiment of the present invention will be described below with reference to the drawings. Note that since the basic configuration of this embodiment is the same as that of the first embodiment, only the characteristic configuration will be described below. This embodiment also includes the third flow channel layer 223 as a lid member, similarly to each of the embodiments described above.

FIGS. 52 and 53 are diagrams showing a liquid ejection unit 800 in this embodiment, and the same parts as in the above-described embodiment are given the same reference numerals and explanations are omitted. 52 is an exploded perspective view of the liquid ejection unit 800, and FIG. 53 is an exploded plan view of the liquid ejection unit 800.

In this embodiment, in order to eject different colors or different types of ink, one liquid ejection unit 800 includes an ejection port array in which ejection ports 13M for the first ink are arranged, and an ejection port array for the second ink. A discharge port array in which 13Y of discharge ports are arranged is formed. The second flow path layer 222 includes a liquid supply path 18M for the first ink, a liquid supply path 18Y for the second ink, a liquid recovery path 19M for the first ink, and a liquid recovery path 19Y for the second ink. It is formed. The third channel layer 223 has a liquid supply opening 2133M for the first ink, a liquid supply opening 2133Y for the second ink, a liquid recovery opening 2143M for the first ink, and a liquid recovery opening 2143Y for the second ink. It is formed. The fourth channel layer 224 includes a common supply channel 2134M for the first ink, a common supply channel 2134Y for the second ink, a common recovery channel 2144M for the first ink, and a common recovery channel 2144Y for the second ink. It is formed. The fifth channel layer 225 includes an individual supply port 2135M for the first ink, an individual supply port 2135Y for the second ink, an individual collection port 2145M for the first ink, and an individual collection port 2145Y for the second ink. It is formed. The sixth channel layer 226 includes a common supply channel 211M for the first ink, a common supply channel 211Y for the second ink, a common recovery channel 212M for the first ink, and a common recovery channel 212M for the second ink. A flow path 212Y is formed.

As in the first application example, each of the first and second inks is supplied from the common supply channels 211M and 211Y, passes through the corresponding pressure chamber 23, and then flows out from the common recovery channels 212M and 212Y. Ru.

Note that, similarly to the fifth embodiment, one liquid supply path may be configured to communicate in common with the pressure chambers of the two ejection port rows, and similarly, the pressure chambers of the two ejection port rows may be configured to communicate with each other in common. The pressure chambers may be configured to communicate with one liquid recovery path in common. Further, the width of the sixth channel layer 226 in the second direction may be set larger than the width of the recording element substrate 10 in the second direction.

In this way, even in a liquid ejection head for multi-color ink or multi-type ink, it is possible to suppress ink circulation amount and pressure variations in each pressure chamber without increasing the width of the liquid supply path and liquid recovery path. . Therefore, a decrease in the ink ejection speed due to evaporation of water in the ink from the ejection port and a change in the coloring material concentration of the ink can be suppressed, and a higher definition and higher quality image can be recorded.

(Arrangement relationship between flow path 18M, flow path 19M, flow path 18Y, and flow path 19Y)
Further, the arrangement relationship between the liquid supply path 18M and the liquid recovery path 19M for the first ink, and the liquid supply path 18Y and the liquid recovery path 19Y for the second ink may be set as follows. That is, as shown in FIG. 54, the beam width of the common outflow channel 19M and the common supply channel 18Y between the first ink ejection port array and the second ink ejection port array is defined as the beam width W4, which is wider than the beam width W1. Set the beam width W4 large. By increasing the beam width W4, it is possible to suppress color mixing due to inflow between the common outflow channel 19M and the common supply channel 18Y. Here, the relationship between the beam width W3 and the beam width W4 may be the same width or different widths. In particular, when the beam width W3 is larger, it is possible to reduce channel pressure loss with respect to ink flow, leading to improved ejection characteristics. In this way, it is possible to suppress the backflow of the ink circulation flow and to suppress the occurrence of ink color mixing while maintaining the pressure in the liquid supply path at a negative pressure.

(Seventh embodiment)
A seventh embodiment of the present invention will be described below. Note that since the basic configuration of this embodiment is the same as that of the first embodiment, only the characteristic configuration will be described below.

This embodiment is a liquid ejection head that does not generate ink circulation flow, unlike the embodiments described above. A supply port, a liquid supply path, a liquid supply opening, an individual supply channel, a communication port, and a common supply port communicate with each discharge port array.

Even in a liquid ejection head that does not generate an ink circulation flow, the shape accuracy of the liquid supply port can be improved by increasing the placement accuracy, so that even in a liquid ejection head with densely arranged ejection ports, variations in flow path resistance, that is, supply during ejection. It is possible to reduce variations in pressure loss occurring in the flow path. Therefore, pressure variations at the ejection port meniscus interface can be reduced and droplets of uniform size can be ejected, making it possible to form images with higher definition and higher quality.

10 recording element substrate 13 ejection port 15 recording element 18 liquid supply path 19 liquid recovery path 20 lid member 23 pressure chamber 300 liquid ejection unit 517 lid member

Claims (21)

The device includes a discharge port for discharging liquid, an element provided corresponding to the discharge port and generating energy for discharging the liquid from the discharge port, and a pressure chamber containing the element inside. multiple element substrates;
A lid member provided on each of the plurality of element substrates, the supply opening being provided on the back surface of the element substrate on the side where the discharge port is formed, for supplying liquid to the pressure chamber, and provided on each of the plurality of element substrates. A liquid ejection head comprising:
A supply path for supplying the liquid supplied from the supply opening to the pressure chamber is provided on the back surface of the element substrate,
A part of the supply path is formed by the lid member,
When the liquid ejection head is viewed from the side facing the ejection port, the outer shape of the lid member is located inside the outer shape of the element substrate on an end side in the longitudinal direction of the element substrate,
The lid member further includes a recovery opening for recovering liquid from the pressure chamber,
A recovery path is further provided on the back surface of the element substrate for recovering the liquid recovered from the pressure chamber of the element substrate to the recovery opening,
A part of the recovery path is formed by the lid member,
A liquid ejection head characterized in that the lid member is a resin film. The device includes a discharge port for discharging liquid, an element provided corresponding to the discharge port and generating energy for discharging the liquid from the discharge port, and a pressure chamber containing the element inside. multiple element substrates;
A lid member provided on each of the plurality of element substrates, the supply opening being provided on the back surface of the element substrate on the side where the discharge port is formed, for supplying liquid to the pressure chamber, and provided on each of the plurality of element substrates. A liquid ejection head comprising:
A supply path for supplying the liquid supplied from the supply opening to the pressure chamber is provided on the back surface of the element substrate,
A part of the supply path is formed by the lid member,
When the liquid ejection head is viewed from the side facing the ejection port, the outer shape of the lid member is located inside the outer shape of the element substrate on an end side in the longitudinal direction of the element substrate,
The lid member further includes a recovery opening for recovering liquid from the pressure chamber,
A recovery path is further provided on the back surface of the element substrate for recovering the liquid recovered from the pressure chamber of the element substrate to the recovery opening,
A part of the recovery path is formed by the lid member,
The lid member is a silicon plate ,
A liquid ejection head characterized in that adjacent element substrates of the plurality of element substrates are arranged so as to partially overlap each other in the longitudinal direction of the liquid ejection head. The device includes a discharge port for discharging liquid, an element provided corresponding to the discharge port and generating energy for discharging the liquid from the discharge port, and a pressure chamber containing the element inside. multiple element substrates;
A lid member provided on each of the plurality of element substrates, the supply opening being provided on the back surface of the element substrate on the side where the discharge port is formed, for supplying liquid to the pressure chamber, and provided on each of the plurality of element substrates. A liquid ejection head comprising:
A supply path for supplying the liquid supplied from the supply opening to the pressure chamber is provided on the back surface of the element substrate,
A part of the supply path is formed by the lid member,
When the liquid ejection head is viewed from the side facing the ejection port, the outer shape of the lid member is located inside the outer shape of the element substrate on an end side in the longitudinal direction of the element substrate,
The lid member further includes a recovery opening for recovering liquid from the pressure chamber,
A recovery path is further provided on the back surface of the element substrate for recovering the liquid recovered from the pressure chamber of the element substrate to the recovery opening,
A part of the recovery path is formed by the lid member,
The outer shape of the element substrate is a parallelogram, and the lengths of diagonal lines on the element substrate are different,
A liquid ejection head characterized in that adjacent element substrates of the plurality of element substrates are arranged so as to partially overlap each other in the longitudinal direction of the liquid ejection head. The device includes a discharge port for discharging liquid, an element provided corresponding to the discharge port and generating energy for discharging the liquid from the discharge port, and a pressure chamber containing the element inside. multiple element substrates;
A lid member provided on each of the plurality of element substrates, the supply opening being provided on the back surface of the element substrate on the side where the discharge port is formed, for supplying liquid to the pressure chamber, and provided on each of the plurality of element substrates. A liquid ejection head comprising:
A supply path for supplying the liquid supplied from the supply opening to the pressure chamber is provided on the back surface of the element substrate,
A part of the supply path is formed by the lid member,
When the liquid ejection head is viewed from the side facing the ejection port, the outer shape of the lid member is located inside the outer shape of the element substrate on an end side in the longitudinal direction of the element substrate,
The lid member further includes a recovery opening for recovering liquid from the pressure chamber,
A recovery path is further provided on the back surface of the element substrate for recovering the liquid recovered from the pressure chamber of the element substrate to the recovery opening,
A part of the recovery path is formed by the lid member,
The plurality of ejection ports form an ejection port array extending in a first direction,
The plurality of element substrates are arranged in the first direction,
The liquid ejection head is characterized in that the element substrates adjacent in the first direction are arranged so as to partially overlap in a direction perpendicular to the first direction. The supply channel and the recovery channel are provided along a first direction, which is a direction in which a row of discharge ports in which a plurality of discharge ports are arranged, correspond to the length of the row of discharge ports. The liquid ejection head according to any one of claims 1 to 4, characterized in that: 6. The liquid ejection head according to claim 5, wherein the supply path and the recovery path are arranged alternately in a second direction intersecting the first direction. The element substrate is provided with a plurality of supply ports for supplying the liquid in the supply path to the pressure chamber and a plurality of recovery ports for recovering the liquid in the pressure chamber to the recovery path. 7. The liquid ejection head according to claim 1, further comprising a liquid ejection head. 8. The liquid ejection head according to claim 7, wherein the supply port and the recovery port are liquid paths having a longitudinal direction in the thickness direction of the element substrate. The liquid ejection head according to claim 1, wherein the thickness of the resin film is less than 25 μm. 10. The liquid ejection head according to claim 1, wherein no adhesive is interposed between the element substrate and the resin film. 9. The device substrate according to claim 1, wherein the outer shape of the element substrate is a parallelogram, and at least one of the supply opening and the recovery opening has a parallelogram shape. Liquid ejection head. Claim 1 or 2, further comprising a support member that supports the element substrate via the resin film, and an adhesive is provided between the support member and the resin film. 9. The liquid ejection head according to 9. 13. The liquid ejection head according to claim 1, wherein a plurality of the supply openings are provided that communicate with one of the supply paths. The supply openings and the recovery openings are arranged alternately with respect to a first direction, which is a direction in which a row of discharge ports in which a plurality of discharge ports are arranged extends. 10. The liquid ejection head according to any one of 10. Adjacent element substrates of the plurality of element substrates are arranged so as to partially overlap each other in the longitudinal direction of the liquid ejection head , or any one of claims 4 to 14. The liquid ejection head described in . The support member supports the plurality of element substrates,
A groove is provided in an adjacent portion of the support member where the element substrate is adjacent to each other, the width of the groove is larger than the width of the gap between the element substrates, and the joint portion between the resin film and the support member is formed in the adjacent portion. 13. The liquid ejection head according to claim 12, wherein the liquid ejection head enters inside from the outer edge of the element substrate. 13. The liquid ejection head according to claim 12, wherein the linear expansion coefficient of the support member is smaller than that of the resin film. having a plurality of supporting members that individually support the element substrate;
13. The liquid ejection head according to claim 12, wherein in an adjacent portion where the element substrates are adjacent to each other, a joint portion between the support member and the resin film enters inside from an outer edge portion of the element substrate. . 19. The liquid ejection head according to claim 1, wherein the liquid ejection head is a page-wide liquid ejection head in which a plurality of the element substrates are arranged in a straight line. 20. The liquid ejection head according to claim 1, wherein the liquid in the pressure chamber is circulated between the liquid and the outside of the pressure chamber. A liquid ejection device comprising the liquid ejection head according to any one of claims 1 to 20.