JP2017124614A - Liquid ejection module and liquid ejection head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid ejection module which can inhibit the occurrence of uneven recording, and a recording element substrate and a liquid ejection head.SOLUTION: A first opening 21 and a second opening 21, which supply liquid to each of first and second liquid supply passages 18, are provided. The center of gravity of the first opening and the center of gravity of the second opening are shifted from a straight line extending in a direction of relative movement.SELECTED DRAWING: Figure 23

Description

  The present invention relates to a liquid discharge module and a liquid discharge head for discharging a liquid such as ink.

  In recent inkjet recording apparatuses, liquid discharge elements are provided at high density in a liquid discharge head in order to enable higher-speed and higher-quality recording. In such a liquid ejection head, the flow path is finer because the flow path is arranged at a higher density than in the prior art.

  When the flow path becomes finer, the flow resistance when the liquid flows increases and the pressure loss increases, so the negative pressure at the discharge port increases, which may affect recording. For example, when the negative pressure increases, the meniscus at the discharge port is drawn into the discharge port, so that the amount of liquid discharged is smaller than when the negative pressure is low. If the amount of liquid ejected is small, the recording density becomes thin and a desired result cannot be obtained.

  Therefore, in Patent Document 1, liquid is supplied through a large flow path until just before the recording element as much as possible, and a fine flow path is formed in the vicinity of the recording element, thereby minimizing pressure loss due to flow resistance and enabling high-speed recording. A recording head assembly is disclosed.

U.S. Pat. No. 7,845,763

  When the large flow path is connected to the fine flow path, the discharge port relatively close to the connection position has a low negative pressure, but the negative pressure increases as the distance from the connection portion increases. In the structure described in Patent Document 1, supply ports for different ejection port arrays are provided at the same position in the recording medium conveyance direction. Therefore, since the discharge port with a low negative pressure and the discharge port with a high negative pressure are in the same position in the transport direction for each discharge port array, the density of the recording density (recording unevenness) appears at the same position in the discharge port array. Will be emphasized and easily visible.

  Accordingly, an object of the present invention is to provide a liquid discharge module and a liquid discharge head that can suppress the occurrence of recording unevenness.

  Therefore, the liquid discharge module of the present invention is a liquid discharge module used in a page-wide liquid discharge head that discharges liquid from a discharge port to a relatively moving recording medium. The first and second ejection port arrays arranged in a direction intersecting with the first direction, and the first and second ejection port arrays supplying liquid to each of the first and second ejection port arrays and extending in the intersecting direction. A recording element substrate including first and second liquid supply paths, and each of the first and second liquid supply paths for supplying liquid to each of the first and second liquid supply paths. A first opening and a second opening communicating with each other, wherein the center of gravity of the first opening and the center of gravity of the second opening are shifted from a straight line extending in the direction of relative movement. And

  According to the present invention, it is possible to realize a liquid ejection module, a recording element substrate, and a liquid ejection head that can suppress the occurrence of recording unevenness.

It is the figure which showed schematic structure of the liquid discharge apparatus which discharges a liquid. It is a schematic diagram which shows the 1st circulation form of the circulation path applied to a recording device. It is a schematic diagram which shows the 2nd circulation form of the circulation path applied to a recording device. FIG. 6 is a schematic diagram illustrating a difference in the amount of ink flowing into a liquid ejection head. It is the perspective view which showed the liquid discharge head. FIG. 6 is an exploded perspective view showing each component or unit constituting the liquid discharge head. It is the figure which showed the surface and back surface of each flow path member of a 1st-3rd flow path member. It is the perspective view shown from the surface where the discharge module of (alpha) part of Fig.7 (a) is mounted. It is the figure which showed the cross section in IX-IX of FIG. It is the perspective view and exploded view which showed one discharge module. FIG. 3 is a diagram illustrating a recording element substrate. FIG. 4 is a perspective view illustrating a cross section of a recording element substrate and a lid member. FIG. 6 is a plan view showing a partially enlarged adjacent portion of a recording element substrate. It is the perspective view which showed the liquid discharge head. It is a perspective exploded view showing a liquid discharge head. It is the figure which showed the 1st flow path member. FIG. 6 is a perspective view illustrating a liquid connection relationship between a recording element substrate and a flow path member. It is the figure which showed the cross section in XVIII-XVIII of FIG. It is the perspective view and exploded view which showed one discharge module. It is a schematic diagram showing a recording element substrate. 1 is a diagram illustrating an ink jet recording apparatus that performs recording by discharging a liquid. FIG. 4 is a diagram illustrating a liquid discharge module of the recording apparatus. FIG. 3 is a diagram illustrating a structure of a recording element substrate. It is the figure which showed the relationship between the position of the opening of a cover member, and the corresponding recording density. FIG. 3 is a diagram illustrating a liquid discharge module and a liquid discharge head of the recording apparatus. FIG. 3 is a diagram illustrating a structure of a recording element substrate. It is the figure which showed the relationship between the position of the opening of a cover member, and the corresponding recording density. It is a figure which shows the recording device of the 1st application example. It is a figure which shows the 3rd circulation form. It is a figure which shows the modification of the liquid discharge head of a 1st application example. It is a figure which shows the modification of the liquid discharge head of a 1st application example. It is a figure which shows the modification of the liquid discharge head of a 1st application example. It is a figure which shows the recording device of the 3rd application example. It is a figure which shows the 4th circulation form. It is a figure which shows the liquid discharge head of the 3rd application example. It is a figure which shows the liquid discharge head of the 3rd application example.

  Hereinafter, first and second application examples to which the present invention can be applied will be described with reference to the drawings.

(First application example)
(Description of inkjet recording apparatus)
FIG. 1 is a diagram showing a schematic configuration of a liquid ejection apparatus for ejecting a liquid according to the present invention, in particular, an ink jet recording apparatus (hereinafter also referred to as a recording apparatus) 1000 that performs recording by ejecting ink. The recording apparatus 1000 includes a transport unit 1 that transports the recording medium 2, and a line type (page wide type) liquid discharge head 3 that is disposed substantially orthogonal to the transport direction of the recording medium 2. The recording apparatus 1000 is a line-type recording apparatus that performs continuous recording in one pass by ejecting ink to a relatively moving recording medium while conveying a plurality of recording media 2 continuously or intermittently. The liquid discharge head 3 includes a negative pressure control unit 230 that controls the pressure (negative pressure) in the circulation path, a liquid supply unit 220 that is in fluid communication with the negative pressure control unit 230, and supply and discharge of ink to the liquid supply unit 220. The liquid connection part 111 used as an exit and the housing 80 are provided. The recording medium 2 is not limited to cut paper but may be a continuous roll medium. The liquid discharge head 3 is capable of full-color recording with cyan C, magenta M, yellow Y, and black K inks, and includes a liquid supply means, a main tank, and a buffer tank (a supply path for supplying liquid to the liquid discharge head 3). Are connected fluidically. The liquid discharge head 3 is electrically connected to an electric control unit that transmits power and a discharge control signal to the liquid discharge head 3. The liquid path and the electric signal path in the liquid discharge head 3 will be described later.

  The recording apparatus 1000 is an ink jet recording apparatus configured to circulate a liquid such as ink between a tank described later and the liquid ejection head 3. The circulation forms are a first circulation form in which two circulation pumps (for high pressure and low pressure) are circulated on the downstream side of the liquid discharge head 3 and two circulations on the upstream side of the liquid discharge head 3. There is a second circulation form in which the pump (for high pressure and low pressure) is circulated by moving. Hereinafter, the first circulation mode and the second circulation mode of the circulation will be described.

(Description of the first circulation mode)
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. In FIG. 2, for the sake of simplicity, only the path through which one of the inks of cyan C, magenta M, yellow Y, and black K flows is shown. A circulation path is provided in the liquid discharge 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 the liquid supply unit 220 of the liquid ejection head 3 through the liquid connection portion 111 by the second circulation pump 1004. To be supplied. Thereafter, the ink adjusted to two different negative pressures (high pressure and low pressure) by the negative pressure control unit 230 connected to the liquid supply unit 220 circulates in two flow paths on the high pressure side and the low pressure side. The ink in the liquid discharge head 3 circulates in the liquid discharge head by the action of the first circulation pump (high pressure side) 1001 and the first circulation pump (low pressure side) 1002 downstream of the liquid discharge head 3, and the liquid connection portion 111. Then, the liquid is discharged from the liquid discharge head 3 and returned to the buffer tank 1003.

  A buffer tank 1003 that is a sub tank is connected to the main tank 1006, has an air communication port (not shown) that communicates the inside and outside of the tank, and can discharge 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 transports ink consumed by ejecting (discharging) ink from the ejection port of the liquid ejection head 3 from the main tank 1006 to the buffer tank 1005, such as recording by discharging the ink and recovery of suction.

  The two first circulation pumps 1001 and 1002 draw liquid from the liquid connection portion 111 of the liquid discharge head 3 and flow it to the buffer tank 1003. As the first circulation pump, a positive displacement pump having a quantitative liquid feeding capacity is preferable. Specific examples include a tube pump, a gear pump, a diaphragm pump, and a syringe pump. For example, a general constant flow valve or a relief valve may be arranged at the pump outlet to ensure a constant flow rate. When the liquid discharge head 3 is driven, the first circulation pump (high-pressure side) 1001 and the first circulation pump (low-pressure side) 1002 are operated, so that the inside of the common supply channel 211 and the common recovery channel 212 have a predetermined flow rate, respectively. Ink flows. By flowing ink in this way, the temperature of the liquid discharge head 3 during recording is maintained at an optimum temperature. The predetermined flow rate at the time of driving the liquid discharge head 3 is preferably set to be equal to or higher than a flow rate that can be maintained so that the temperature difference between the recording element substrates 10 in the liquid discharge head 3 does not affect the recording image quality. However, if the flow rate is set too high, the negative pressure difference is increased in each recording element substrate 10 due to the pressure loss of the flow path in the liquid discharge unit 300, resulting in uneven density of the image. Therefore, it is preferable to set the flow rate in consideration of the temperature difference and the negative pressure difference between the recording element substrates 10.

  The negative pressure control unit 230 is provided in a path between the second circulation pump 1004 and the liquid discharge unit 300. The negative pressure control unit 230 controls the pressure downstream of the negative pressure control unit 230 (that is, the liquid discharge unit 300 side) even when the ink flow rate in the circulation system fluctuates due to a difference in the discharge amount per unit area. It operates to maintain a preset constant pressure. As the two negative pressure control mechanisms constituting the negative pressure control unit 230, as long as the pressure downstream of the negative pressure control unit 230 can be controlled with a fluctuation within a certain range around a desired set pressure, Any mechanism may be used. As an example, a mechanism similar to a so-called “pressure reduction regulator” can be employed. 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 on the liquid discharge head 3 of the buffer tank 1003 can be suppressed, so that the layout flexibility of the buffer tank 1003 in the recording apparatus 1000 can be expanded.

  The second circulation pump 1004 may be any pump that has a lift pressure that is equal to or higher than a certain pressure in the range of the ink circulation flow rate that is used when the liquid discharge head 3 is driven, and a turbo pump or a positive displacement pump can be used. 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 can be applied. 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) pass through the liquid supply unit 220, respectively. Thus, the common supply flow path 211 and the common recovery flow path 212 in the liquid discharge unit 300 are connected. The liquid discharge 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 flow path 211, and a negative pressure control mechanism L is connected to the common recovery flow path 212, and a differential pressure is generated between the two common flow paths. Since the individual flow path 215 communicates with the common supply flow path 211 and the common recovery flow path 212, a part of the liquid passes through the internal flow path of the recording element substrate 10 from the common supply flow path 211. A flow (arrow in FIG. 2) flowing to the common recovery flow path 212 is generated.

  In this way, in the liquid ejection unit 300, a part of the liquid passes through each recording element substrate 10 while flowing the liquid so as to pass through the common supply flow path 211 and the common recovery flow path 212. 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. Further, with such a configuration, when recording is performed by the liquid ejection head 3, it is possible to cause ink to flow even in ejection ports and pressure chambers where ejection is not performed. As a result, the viscosity of the ink that has increased in viscosity within the ejection port is reduced, thereby suppressing the increase in the viscosity of the ink. Further, the thickened ink and the foreign matter in the ink can be discharged to the common recovery channel 212. For this reason, the liquid discharge head 3 of this application example can perform high-speed and high-quality recording.

(Description of second circulation mode)
FIG. 3 is a schematic diagram illustrating a second circulation form that is a circulation form different from the first circulation form described above, among the circulation paths applied to the recording apparatus of the present application example. The main difference from the first circulation mode described above is that the two negative pressure control mechanisms constituting the negative pressure control unit 230 both have a pressure upstream of the negative pressure control unit 230 and a desired set pressure. It is a point to control by fluctuation within a certain range as the center. Further, as a difference from the first circulation mode, there is a point that the second circulation pump 1004 acts as a negative pressure source for depressurizing 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. This is also different.

  In the second circulation mode, the 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 the two flow paths on the high-pressure side and the low-pressure side is supplied to the liquid discharge head 3 via the liquid connection portion 111 by the action of the first circulation pump (high-pressure side) 1001 and the first circulation pump (low-pressure side) 1002. To be supplied. Thereafter, the ink circulated in the liquid discharge head by the action of the first circulation pump (high-pressure side) 1001 and the first circulation pump (low-pressure side) 1002 passes through the negative pressure control unit 230 and passes through the liquid connection portion 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 has a pressure on the upstream side (that is, the liquid discharge unit 300 side) of the negative pressure control unit 230 even if the flow rate varies due to a change in the discharge amount per unit area. The fluctuation is stabilized within a certain range around a preset pressure. In the circulation channel 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, since the influence of the water head pressure of the buffer tank 1003 on the liquid discharge head 3 can be suppressed, the selection range of the layout of the buffer tank 1003 in the recording apparatus 1000 can be widened. 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 can be applied. In the second circulation mode, similarly to the first circulation mode, the negative pressure control unit 230 includes two negative pressure control mechanisms in which different control pressures are set. Of the two negative pressure adjusting mechanisms, the high pressure setting side (denoted as H in FIG. 3) and the low pressure setting side (denoted as L in FIG. 3) pass through the liquid supply unit 220, respectively, in the liquid discharge unit 300. Are connected to the common supply channel 211 or the common recovery channel 212. By making the pressure of the common supply flow path 211 relatively higher than the pressure of the common recovery flow path 212 by two negative pressure adjusting mechanisms, the internal flow paths from the common supply flow path 211 to the individual flow paths 215 and the inside of each recording element substrate 10 A liquid flow that flows to the common recovery channel 212 via the channel is generated.

  In such a second circulation mode, the same liquid flow state as in the first circulation mode can be obtained in the liquid discharge unit 300, but there are two advantages different from those in 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 discharge head 3, so that dust and foreign matter generated from the negative pressure control unit 230 are transferred to the liquid discharge head 3. There are few concerns about inflow. The second advantage is that, in the second circulation mode, the maximum required flow rate 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 total 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 in the liquid discharge unit 300 within a desired range when adjusting the temperature of the liquid discharge head 3 during recording standby. Further, a discharge flow rate when ink is discharged from all the discharge ports of the liquid discharge unit 300 (at the time of full discharge) is defined as a flow rate F (discharge amount per discharge port × discharge frequency per unit time × number of discharge 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. 4A shows a standby time in the first circulation mode, and FIG. 4B shows a full discharge time in the first circulation mode. FIGS. 4 (c) to 4 (f) show the second circulation flow path. FIGS. 4 (c) and 4 (d) show the case where the flow rate F <the flow rate A, and FIGS. ) Is the case where the flow rate F> the flow rate A, and shows the flow rates during standby and full discharge, respectively.

  In the case of the first circulation mode in which the first circulation pump 1001 and the first circulation pump 1002 having a quantitative liquid feeding capacity are arranged on the downstream side of the liquid discharge head 3 (FIGS. 4A and 4B). The total set flow rate of the first circulation pump 1001 and the first circulation pump 1002 is the flow rate A. With this flow rate A, the temperature in the liquid discharge unit 300 during standby can be managed. When total discharge is performed by the liquid discharge head 3, 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 caused by the negative pressure generated by the ejection of the liquid ejection head 3, and the flow rate F corresponding to the total ejection is added to the total flow rate A. Therefore, since the flow rate F is added to the flow rate A, the maximum value of the supply amount to the liquid ejection head 3 becomes the flow rate A + the flow rate F (FIG. 4B).

  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 on the upstream side of the liquid discharge head 3 (FIG. 4C to FIG. 4F), recording is performed. The amount of supply to the liquid discharge head 3 required during standby 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 on the upstream side of the liquid discharge head 3, the flow rate A is greater than the flow rate F (FIG. 4C) ( For d)), the flow rate A is sufficient for the supply amount to the liquid discharge head 3 even during the entire discharge. At that time, the discharge flow rate from the liquid discharge head 3 is flow rate A−flow rate F (FIG. 4D). However, when the flow rate F is higher than the flow rate A (FIGS. 4E and 4F), the flow rate becomes insufficient if the supply flow rate to the liquid ejection head 3 is the flow rate A at the time of full ejection. Therefore, when the flow rate F is higher than the flow rate A, the supply amount to the liquid ejection head 3 needs to be the flow rate F. At this time, if the full discharge is performed, the flow rate F is consumed in the liquid discharge head 3, and therefore, the discharge flow rate from the liquid discharge head 3 is hardly discharged (FIG. 4F). When the flow rate F is higher than the flow rate A and discharge is performed but not all discharges, an amount obtained by subtracting the amount consumed by the discharge from the flow rate F is discharged from the liquid discharge head 3. When the flow rate A and the flow rate F are equal, the flow rate A (or flow rate F) is supplied to the liquid discharge head 3 and the flow rate F is consumed in the liquid discharge head 3. The discharge flow rate is almost not discharged.

  As described above, 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 necessary supply flow rate is the larger value of the flow rate A or the flow rate F. Become. For this reason, as long as the liquid discharge unit 300 having the same configuration is used, the maximum value of the required supply amount (flow rate A or flow rate F) in the second circulation mode is the maximum value (flow rate) of the required supply flow rate in the first circulation mode. A + flow rate F).

  Therefore, in the case of the second circulation mode, the degree of freedom of the applicable circulation pump is increased. For example, a low-cost circulation pump having a simple configuration or a load of a cooler (not shown) installed in the main body side path is used. There is an advantage that the cost of the recording apparatus can be reduced. This advantage increases as the line head has a relatively large value of the flow rate A or the flow rate F. Among line heads, a line head having a long length in the longitudinal direction is more beneficial.

  On the other hand, however, the first circulation mode is advantageous over the second circulation mode. That is, in the second circulation mode, since the flow rate flowing through the liquid ejection unit 300 is maximum during recording standby, the smaller the amount of ejection per unit area (hereinafter also referred to as a low duty image), the more each ejection port. In this state, a high negative pressure is applied. For this reason, when the flow path width is narrow and the negative pressure is high, a high negative pressure is applied to the discharge port in a low-duty image in which unevenness is easily visible, so that many so-called satellite droplets are discharged along with the main ink droplets. It may occur and the recording quality may deteriorate.

  On the other hand, in the first circulation mode, a high negative pressure is applied to the discharge port at the time of forming an image having a large discharge amount per unit area (hereinafter also referred to as a high duty image). Even if it occurs, there is an advantage that it is difficult to visually recognize and the influence on the image is small. These two circulation modes can be selected in light of the specifications of the liquid discharge head and the recording apparatus main body (discharge flow rate F, minimum circulation flow rate A, and in-head flow path resistance).

(Description of third circulation mode)
FIG. 29 is a schematic diagram showing a third circulation form which is one form of a circulation path applied to the recording apparatus of the present embodiment. A description of functions and configurations similar to those of the first and second circulation paths will be omitted, and different points will be mainly described.

  In this circulation path, the liquid is supplied into the liquid discharge head 3 from two places in the center of the liquid discharge head 3 and three places on one end side of the liquid discharge head 3. The liquid passes through the pressure chambers 23 from the common supply flow path 211 and is then recovered in the common recovery flow path 212 and is recovered to the outside from the recovery opening at the other end of the liquid discharge head 3. The individual flow path 213 communicates with the common supply path 211 and the common recovery flow path 212, and the recording element substrate 10 and the pressure chamber 23 disposed in the recording element substrate are provided in the path of each individual flow path 213. ing. Therefore, a part of the liquid flowing in the first circulation pump 1002 passes through the pressure chamber 23 of the recording element substrate 10 from the common supply channel 211 and flows into the common recovery channel 212 (arrow in FIG. 29). This is because a pressure difference is provided between the pressure adjustment mechanism H connected to the common supply flow path 211 and the pressure adjustment mechanism L connected to the common recovery flow path 212, so that the first circulation pump 1002 can perform the common recovery flow. This is because it is connected only to the path 212.

  In this way, in the liquid ejection unit 300, the liquid flow that passes through the common recovery channel 212 and the common recovery channel that passes from the common supply channel 211 to the pressure chamber 23 in each recording element substrate 10. A flow occurs at 212. Therefore, heat generated in each recording element substrate 10 can be discharged to the outside of the recording element substrate 10 by the flow from the common supply channel 211 to the common recovery channel 212 while suppressing an increase in pressure loss. Further, according to this circulation path, it is possible to reduce the number of pumps which are liquid transporting means as compared with the first and second circulation paths.

(Description of liquid discharge head configuration)
The configuration of the liquid ejection head 3 according to the first application example will be described. FIG. 5A and FIG. 5B are perspective views showing the liquid ejection head 3 according to this application example. In the liquid discharge head 3, 15 recording element substrates 10 capable of discharging ink of four colors of cyan C / magenta M / yellow Y / black K are arranged in a straight line (arranged inline). This is a line type liquid discharge head. As shown in FIG. 5A, the liquid ejection head 3 is electrically connected to each recording element substrate 10 via a flexible wiring substrate 40 and an electric wiring substrate 90 that can supply electric energy to the recording element substrate 10. A signal input terminal 91 and a power supply terminal 92 are provided. The signal input terminal 91 and the power supply terminal 92 are electrically connected to the control unit of the recording apparatus 1000, and supply an ejection drive signal and electric power necessary for ejection to the recording element substrate 10, respectively. By consolidating the wiring by the electric circuit in the electric wiring board 90, the number of the signal input terminals 91 and the power supply terminals 92 can be reduced as compared with the number of the recording element boards 10. This reduces the number of electrical connections that need to be removed when the liquid ejection head 3 is assembled to the recording apparatus 1000 or when the liquid ejection head is replaced. As shown in FIG. 5B, the liquid connection portions 111 provided at both ends of the liquid ejection head 3 are connected to the liquid supply system of the recording apparatus 1000. Accordingly, cyan C / magenta M / yellow Y / black K four color inks are supplied from the supply system of the recording apparatus 1000 to the liquid discharge head 3, and ink that has passed through the liquid discharge head 3 is supplied to the supply system of the recording apparatus 1000. It has come to be collected. As described above, the ink of each color can be circulated through the path of the recording apparatus 1000 and the path of the liquid discharge head 3.

  FIG. 6 is an exploded perspective view showing each component or unit constituting the liquid ejection head 3. The liquid discharge unit 300, the liquid supply unit 220, and the electric wiring substrate 90 are attached to the housing 80. The liquid supply unit 220 is provided with a liquid connection portion 111 (see FIG. 3), and the liquid supply unit 220 communicates with each opening of the liquid connection portion 111 in order to remove foreign matter in the supplied ink. A filter 221 (see FIGS. 2 and 3) for each color is 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 the negative pressure control unit 230 disposed on the liquid supply unit 220 corresponding to each color. The negative pressure control unit 230 is a unit composed of a negative pressure control valve for each color, and the inside of the supply system of the recording apparatus 1000 that is generated in accordance with the fluctuation of the liquid flow rate by the action of a valve, a spring member, or the like provided in each of the negative pressure control units. A change in pressure loss of the (supply system upstream of the liquid discharge head 3) is greatly attenuated. Thus, the negative pressure control unit 230 can stabilize the negative pressure change on the downstream side (liquid ejection unit 300 side) from the negative pressure control unit within a certain range. In the negative pressure control unit 230 for each color, two negative pressure control valves for each color are incorporated as described in FIG. The two negative pressure control valves are set to different control pressures, and the high pressure side is supplied with the common supply channel 211 (see FIG. 2) in the liquid discharge unit 300, and the low pressure side is supplied with the common recovery channel 212 (see FIG. 2). It communicates via the unit 220.

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

  The liquid discharge unit 300 includes a plurality of discharge modules 200 and a flow path member 210, and a cover member 130 is attached to the surface of the liquid discharge unit 300 on the recording medium side. Here, the cover member 130 is a member having a frame-like surface provided with a long opening 131 as shown in FIG. 6. From the opening 131, the recording element substrate 10 included in the discharge module 200 and the sealing member 130 are sealed. The stop member 110 (see FIG. 10 described later) is exposed. The frame portion around the opening 131 functions as a contact surface of a cap member that caps the liquid ejection head 3 during recording standby. For this reason, a closed space is formed at the time of capping by applying an adhesive, a sealing material, a filler, or the like along the periphery of the opening 131 and filling 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 discharge unit 300 will be described. As shown in FIG. 6, the flow path member 210 is a laminate of the first flow path member 50, the second flow path member 60, and the third flow path member 70, and allows the liquid supplied from the liquid supply unit 220 to flow. Distribute to each discharge module 200. 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 discharge unit support portion 81 with screws, thereby suppressing warpage and deformation of the flow path member 210.

  FIGS. 7A to 7F are views showing the front and back surfaces of each flow path member of the first to third flow path members. 7A shows a surface of the first flow path member 50 on the side where the discharge module 200 is mounted, and FIG. 7F shows a liquid discharge unit support portion 81 of the third flow path member 70. The surface on the abutting side is shown. The first flow path member 50 and the second flow path member 60 are joined so that FIG. 7B and FIG. 7C, which are contact surfaces of the respective flow path members, face each other. The member and the third flow path member are joined so that FIG. 7D and FIG. 7E which are contact surfaces of the respective flow path members face each other. By joining the second flow path member 60 and the third flow path member 70, the eight flow paths extending in the longitudinal direction of the flow path member from the common flow path grooves 62 and 71 formed in each flow path member. Common flow paths (211a, 211b, 211c, 211d, 212a, 212b, 212c, 212d) are formed. As a result, a set of the common supply channel 211 and the common recovery channel 212 is formed in the channel member 210 for each color. Ink is supplied from the common supply flow path 211 to the liquid discharge head 3, and the ink supplied to the liquid discharge head 3 is recovered by the common recovery flow path 212. The communication port 72 (see FIG. 7F) of the third flow path member 70 communicates with each hole of the joint rubber 100, and fluidly circulates with the liquid supply unit 220 (see FIG. 6). On the bottom surface of the common channel groove 62 of the second channel member 60, there are communication ports 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). A plurality are formed and communicate with one end of the individual flow channel 52 of the first flow channel member 50. A communication port 51 is formed at the other end of the individual flow channel 52 of the first flow channel member 50, and is in fluid communication with the plurality of discharge modules 200 via the communication port 51. The individual flow channel 52 enables the flow channels to be concentrated on the center side of the flow channel member.

  It is preferable that the first to third flow path members are made of a material having corrosion resistance against a liquid and a low linear expansion coefficient. As the material, for example, a composite material (aluminum, LCP (liquid crystal polymer), PPS (polyphenyl sulfide), PSF (polysulfone), or modified PPE (polyphenylene ether)) as a base material and an inorganic filler such as silica fine particles or fibers added ( Resin material) can be suitably used. As a method of forming the flow path member 210, three flow path members may be laminated and bonded to each other. When 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. 7A, and the flow path in the flow path member 210 formed by joining the first to third flow path members is the first flow path member 50. It is the perspective view which expanded and showed a part from the surface side in which the discharge module 200 is mounted. The common supply flow path 211 and the common recovery flow path 212 are alternately arranged from the flow paths at both ends. Here, the connection relation of each flow path in the flow path member 210 will be described.

  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 has been. A plurality of individual supply channels 213 (213 a, 213 b, 213 c, and 213 d) formed by the individual channel grooves 52 are connected to the common supply channel 211 of each color via the communication port 61. A plurality of individual recovery channels 214 (214a, 214b, 214c, 214d) formed by the individual channel grooves 52 are connected to the common recovery channel 212 of each color via the communication port 61. With such a flow path configuration, it is possible to collect ink from each common supply flow path 211 via the individual supply flow path 213 to the recording element substrate 10 located at the center of the flow path member. Ink can be recovered from the recording element substrate 10 to each common recovery channel 212 via the individual recovery channel 214.

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

  Here, the common supply flow path 211 of each color is connected to the corresponding negative pressure control unit 230 (high pressure side) via the liquid supply unit 220, and the common recovery flow path 212 is connected to the negative pressure control unit 230. (Low pressure side) and the liquid supply unit 220 are connected. By this negative pressure control unit 230, a differential pressure (pressure difference) is generated between the common supply channel 211 and the common recovery channel 212. For this reason, as shown in FIGS. 8 and 9, in the liquid discharge head of this application example in which the flow paths are connected, the common supply flow path 211 to the individual supply flow paths 213 to the recording element substrates 10 to 10 are individually used for each color. A flow that flows in order from the recovery channel 214 to the common recovery channel 212 is generated.

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

(Description of structure of recording element substrate)
FIG. 11A shows a plan view of the surface of the recording element substrate 10 on which the ejection port 13 is formed, and FIG. 11B shows an enlarged view of the portion indicated by A in FIG. FIG.11 (c) shows the top view of the back surface 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, the four ejection port arrays corresponding to the respective ink colors are formed on the ejection port forming member 12 of the recording element substrate 10. Hereinafter, the direction in which the discharge port array in which the plurality of discharge ports 13 are arranged is referred to as “discharge port array direction”. As shown in FIG. 11B, recording elements 15 that are ejection energy generating elements for foaming liquid using thermal energy are arranged at positions corresponding to the ejection ports 13. A partition 22 defines a pressure chamber 23 having the recording element 15 therein. The recording element 15 is electrically connected to the terminal 16 by electrical wiring (not shown) provided on the recording element substrate 10. The recording element 15 generates heat based on the 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) to boil the liquid. Let The liquid is discharged from the discharge port 13 by the foaming force due to the boiling. As shown in FIG. 11B, along each discharge port array, 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 channels extending in the direction of the discharge port array provided in the recording element substrate 10 and communicate with the discharge port 13 via the supply port 17a and the recovery port 17b, respectively.

  As shown in FIG. 11C, a sheet-like lid member 20 is laminated on the back surface of the recording element substrate 10 on which the discharge port 13 is formed. In addition, a plurality of openings 21 communicating with the liquid recovery path 19 are provided. In this application example, three openings 21 are provided in the lid member 20 for one liquid supply path 18 and two openings 21 for one liquid recovery path 19. As shown in FIG. 11B, each opening 21 of the lid member 20 communicates with a plurality of communication ports 51 shown in FIG. The lid member 20 is preferably a material having sufficient corrosion resistance to the liquid, and high accuracy is required for the opening shape and the opening position of the opening 21 from the viewpoint of preventing color mixing. 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 provide the opening 21 by a photolithography process. As described above, the lid member 20 converts the pitch of the flow path by the openings 21, and it is desirable that the thickness is thin in consideration of the pressure loss, and it is desirable that the lid member 20 is formed of a film-like member.

  FIG. 12 is a perspective view showing a cross section of the recording element substrate 10 and the lid member 20 in XII-XII of FIG. Here, the flow of the liquid in the recording element substrate 10 will be described. 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 formed of Si and a discharge port forming member 12 formed of a photosensitive resin, 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 thereof. Grooves are formed. The liquid supply path 18 and the liquid recovery path 19 formed by the substrate 11 and the lid member 20 are connected to the common supply path 211 and the common recovery path 212 in the flow path member 210, respectively. And a liquid recovery path 19 has a differential pressure. When recording is performed by discharging liquid from the discharge port 13, the liquid in the liquid supply path 18 provided in the substrate 11 is supplied to the supply ports 17 a and 17 a by the differential pressure. It flows to the liquid recovery path 19 via the pressure chamber 23 and the recovery port 17b (arrow C in FIG. 12). By this flow, it is possible to collect the thickened ink, bubbles, foreign matters, and the like generated by evaporation from the ejection port 13 in the liquid recovery path 19 in the ejection port 13 and the pressure chamber 23 where recording is paused. Further, it is possible to prevent the ink in the ejection port 13 and the pressure chamber 23 from being thickened. The liquid recovered into the liquid recovery path 19 passes through the opening 21 of the lid member 20 and the liquid communication port 31 of the support member 30 (see FIG. 10B), and the communication port 51 (see FIG. 7A) in the flow path member 210. The individual collection channel 214 and the common collection channel 212 are collected in this order. Then, the liquid is recovered to the recovery path of the recording apparatus 1000. That is, the liquid supplied from the recording apparatus main body to the liquid discharge head 3 flows in the following order, and is supplied and recovered.

  The liquid first flows into the liquid ejection head 3 from the liquid connection part 111 of the liquid supply unit 220. The liquid is the joint rubber 100, the communication port 72 and the common channel groove 71 provided in the third channel member, the common channel groove 62 and the communication port 61 provided in the second channel member, and the first channel. The individual flow channel 52 and the communication port 51 provided in the member are supplied in this order. Thereafter, the pressure 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 17 a in this order. Of the liquid supplied to the pressure chamber 23, the liquid that has not been discharged from the discharge port 13 is the recovery port 17 b 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. It flows through the liquid communication port 31 provided in the order. Thereafter, the liquid is provided in the communication port 51 and the individual flow channel 52 provided in the first flow channel member, the communication port 61 and the common flow channel 62 provided in the second flow channel member, and the third flow channel member 70. The common channel groove 71, the communication port 72, and the joint rubber 100 are sequentially flowed. Then, the liquid flows from the liquid connection part 111 provided in the liquid supply unit 220 to the outside of the liquid discharge head 3.

  In the form of the first circulation form shown in FIG. 2, the liquid flowing in from the liquid connecting portion 111 is supplied to the joint rubber 100 after passing through the negative pressure control unit 230. In the second circulation form 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 unit 111 to the liquid discharge head. Flow outside. Further, not all the liquid that has flowed 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. That is, there is a liquid that flows from one end of the common supply channel 211 and flows from the other end of the common supply channel 211 to the liquid supply unit 220 without flowing into the individual supply channel 213a. As described above, by providing a path that flows without passing through the recording element substrate 10, even when the recording element substrate 10 including a fine flow path having a high flow resistance is provided as in this application example, The reverse flow of the circulating flow can be suppressed. As described above, in the liquid discharge head 3 of this application example, it is possible to suppress the increase in the viscosity of the liquid in the pressure chamber 23 and the vicinity of the discharge port. High-quality recording can be performed.

(Description of positional relationship between recording element substrates)
FIG. 13 is a plan view partially enlarged showing the adjacent portion of the recording element substrate in two adjacent ejection modules. In this application example, a substantially parallelogram recording element substrate is used. The ejection port arrays (14 a to 14 d) in which the ejection ports 13 in each recording element substrate 10 are arranged are arranged so as to be inclined at a certain angle with respect to the longitudinal direction of the liquid ejection head 3. The ejection port arrays in the adjacent portions of the recording element substrates 10 are configured such that at least one ejection port overlaps in the conveyance direction of the recording medium. In FIG. 13, the two discharge ports on the line D are in a relationship of overlapping each other. With such an arrangement, even if the position of the recording element substrate 10 is slightly deviated from the predetermined position, black stripes and white spots in the recorded image can be made inconspicuous by driving control of the overlapping discharge 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 recording elements are controlled while suppressing an increase in the length of the liquid ejection head 10 in the recording medium conveyance direction by the configuration as shown in FIG. It is possible to take measures against black streaks and white spots at the connecting portions of the substrates 10. In this application example, the main plane of the recording element substrate is a parallelogram, but the present invention is not limited to this, and the configuration of the present invention is preferable even when a recording element substrate having a rectangular shape, trapezoid, or other shape is used. Can be applied.

(Description of Modification of Liquid Discharge Head Configuration)
A modification of the liquid ejection head configuration described above with reference to FIGS. 28 and 30 to 32 will be described. A description of the same configuration and function as those in the above-described example will be omitted, and different points will be mainly described. In this modification, as shown in FIGS. 28 and 30, a plurality of liquid connection portions 111, which are liquid connection portions between the liquid discharge head 3 and the outside, are collectively arranged on one end side in the longitudinal direction of the liquid discharge head. Has been. A plurality of negative pressure control units 230 are collectively arranged on the other end side of the liquid discharge head 3 (FIG. 31). The liquid supply unit 220 included in the liquid discharge head 3 is configured as a long unit corresponding to the length of the liquid discharge head 3 and includes a flow path and a filter 221 corresponding to the four colors of liquid to be supplied. As shown in FIG. 31, the positions of the openings 83 to 86 provided in the liquid discharge unit support portion 81 are also provided at positions different from the liquid discharge head 3 described above.

  FIG. 32 shows a stacked state of the flow path members 50, 60, and 70. As shown in FIG. A plurality of recording element substrates 10 are linearly arranged on the upper surface of the channel member 50 that is the uppermost layer of the plurality of channel members 50, 60, 70. The flow paths communicating with the openings 21 (FIG. 20C) formed on the back side of each recording element substrate 10 are two individual supply flow paths 213 and one individual recovery flow path 214 for each liquid color. It has become one. Correspondingly, the opening 21 formed in the lid member 20 provided on the back surface of the recording element substrate 10 also has two supply openings 21 and one recovery opening 21 for each liquid color. As shown in FIG. 32, common supply channels 211 and common recovery channels 212 extending along the longitudinal direction of the liquid ejection head 3 are alternately arranged in parallel.

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

(Description of inkjet recording apparatus)
FIG. 21 is a diagram showing an ink jet recording apparatus 2000 that performs recording by discharging a liquid, to which the present application example can be applied. The recording apparatus 2000 according to this application example performs full-color recording on a recording medium by arranging four monochromatic liquid ejection heads 2003 corresponding to each of cyan C, magenta M, yellow Y, and black K in parallel. Is different from the first application example. In the first application example, the number of discharge port rows that can be used per color is one, whereas in this application example, the number of discharge port rows that can be used per color is 20. For this reason, it is possible to perform very high-speed recording by appropriately recording the recording data to a plurality of ejection port arrays. Furthermore, even if there is a discharge port that does not discharge, reliability is improved by performing complementary discharge from the discharge ports in other rows that are in positions corresponding to the transport direction of the recording medium with respect to that discharge port. And suitable for commercial records. As in the first application example, the supply system of the recording apparatus 2000, the buffer tank 1003 (see FIGS. 2 and 3), and the main tank 1006 (see FIGS. 2 and 3) are fluids for each liquid discharge head 2003. Connected. Each liquid discharge head 2003 is electrically connected to an electric control unit that transmits power and a discharge control signal to the liquid discharge head 2003.

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

(Description of liquid discharge head structure)
14A and 14B are perspective views showing a liquid discharge head 2003 according to this application example. Here, the structure of the liquid discharge head 2003 according to this application example will be described. The liquid discharge head 2003 includes 16 recording element substrates 2010 arranged linearly in the longitudinal direction of the liquid discharge head 2003, and is an ink jet line type (page wide type) recording capable of recording with one type of liquid. Head. The liquid discharge head 2003 includes a liquid connection unit 111, a signal input terminal 91, and a power supply terminal 92, as in the first application example. However, since the liquid discharge head 2003 of this application example has more discharge 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 discharge head 2003. This is to reduce voltage drop and signal transmission delay that occur in the wiring portion provided on the recording element substrate 2010.

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

  The two negative pressure control units 2230 are set so as to control the pressure with different relatively high and low negative pressures. As shown in FIGS. 14 and 15, when the negative pressure control units 2230 on the high pressure side and the low pressure side are installed at both ends of the liquid discharge head 2003, the common supply extending in the longitudinal direction of the liquid discharge head 2003 is provided. The liquid flows in the channel and the common recovery channel face each other. In such a configuration, heat exchange is promoted between the common supply channel and the common recovery channel, and a temperature difference between the two common channels is reduced. Accordingly, there is an advantage that a temperature difference in each of the 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 flow path member 2210 of the liquid discharge unit 2300 will be described. As shown in FIG. 15, the flow path member 2210 is formed by stacking the first flow path member 2050 and the second flow path member 2060, and distributes the liquid supplied from the liquid supply unit 2220 to each discharge module 2200. To do. 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 has a function of mainly responsible for the rigidity of the liquid discharge head 2003. For this reason, as a material of the 2nd flow path member 2060, what has sufficient corrosion resistance with respect to a liquid and high mechanical strength is preferable. Specifically, SUS, Ti, alumina or the like can be used.

  FIG. 16A is a view showing a surface of the first flow path member 2050 on which the discharge module 2200 is mounted, and FIG. 16B shows the back surface thereof, and the second flow path member 2060 is shown. It is the figure which showed the surface contact | abutted with. Unlike the first application example, the first flow path member 2050 in this application example is obtained by arranging a plurality of members corresponding to each discharge module 2200 adjacent to each other. By adopting such a divided structure, a plurality of modules can be arranged to correspond to the length of the liquid discharge head 2003. For example, a relatively long scale corresponding to the B2 size or longer The present invention can be particularly preferably applied to the liquid discharge head. As shown in FIG. 16A, 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 is in fluid communication with the communication port 61 of the second flow path member 2060. FIG. 16C shows a surface of the second flow path member 60 that comes into contact with the first flow path member 2050, and FIG. 16D shows a cross section of the central portion in the thickness direction of the second flow path member 60. FIG. 16E is a diagram showing a 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 the communication port of the second flow path member 2060 are the same as for one color in the first application example. One of the common flow channel grooves 71 of the second flow channel member 2060 is a common supply flow channel 2211 shown in FIG. 17 to be described later, and the other is a common recovery flow channel 2212. The longitudinal direction of the liquid discharge head 2003, respectively. The liquid is supplied from one end side to the other end side. This application example is different from the first application example, and 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 a liquid connection relationship between the recording element substrate 2010 and the flow path member 2210. In the flow path member 2210, a set of a common supply flow path 2211 and a common recovery flow path 2212 extending in the longitudinal direction of the liquid discharge head 2003 are provided. The communication port 61 of the second flow channel member 2060 is connected to the individual communication port 53 of the first flow channel member 2050 in alignment, and is connected to the common supply flow channel 2211 of the second flow channel member 2060 via the communication port 61. Thus, 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 that communicates from the communication port 72 of the second flow channel member 2060 to the communication port 51 of the first flow channel member 2050 via the common recovery flow channel 2212 is also formed.

  18 is a view showing a cross section taken along line XVIII-XVIII in FIG. 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 flow path 2212 is connected to the discharge module 2200 through a similar path. As in the first application example, each ejection module 2200 and the recording element substrate 2010 are formed with a flow path communicating with each ejection port, and part or all of the supplied liquid pauses the ejection operation. It can be recirculated through the outlet. Similarly to the first application example, the common supply flow path 2211 is connected to the negative pressure control unit 2230 (high pressure side), and the common recovery flow path 2212 is connected to the negative pressure control unit 2230 (low pressure side) and the liquid supply unit 2220. Connected. Therefore, a flow that flows from the common supply channel 2211 through the pressure chamber of the recording element substrate 2010 to the common recovery channel 2212 is generated by the differential pressure.

(Description of discharge module)
FIG. 19A is a perspective view showing one discharge module 2200, and FIG. 19B is an exploded view thereof. The difference from the first application example is that a plurality of terminals 16 are arranged on both sides (long sides of the printing element substrate 2010) along the plurality of ejection port array directions of the printing element substrate 2010, respectively. is there. Accordingly, two flexible wiring boards 40 that are electrically connected to the recording element substrate 2010 are also arranged on one recording element substrate 2010. This is because the number of ejection port arrays provided on the recording element substrate 2010 is 20, which is significantly larger than the eight arrays in the first application example, and the maximum distance from the terminal 16 to the recording element is shortened. This is to reduce a voltage drop and a signal delay that occur in the wiring portion in 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 is opened so as to straddle all the ejection port arrays. The other points are the same as in the first application example.

(Description of structure of recording element substrate)
FIG. 20A is a schematic diagram of the surface on which the ejection port 13 of the recording element substrate 2010 is arranged, and FIG. 20C is a schematic diagram showing the back surface of the surface of FIG. FIG. 20B 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 is removed in FIG. As shown in FIG. 20B, the liquid supply path 18 and the liquid recovery path 19 are alternately provided on the back surface of the recording element substrate 2010 along the discharge port array direction. Although the number of ejection port arrays is significantly increased as compared with the first application example, the essential difference from the first application example is that the terminals 16 are arranged in the ejection port array direction of the recording element substrate as described above. It is arranged on both sides along. One set of the liquid supply path 18 and the liquid recovery path 19 is provided for each discharge port array, the opening 21 communicating with the liquid communication port 31 of the support member 2030 is provided in the lid member 2020, and the like. The basic configuration is the same as that of the first application example.

(Third application example)
The configurations of the ink jet recording apparatus 1000 and the liquid discharge head 3 according to the third application example of the present invention will be described. The liquid ejection head of the third application example is a page-wide type that performs recording in one scan on a B2 size recording medium. Since the third application example is similar in many respects to the second application example, in the following description, parts different from the second application example will be mainly described, and parts similar to the second application example will be described. Is omitted.

(Description of inkjet recording apparatus)
FIG. 33 is a schematic diagram of an ink jet recording apparatus according to this application example. The recording apparatus 1000 does not perform direct recording on the recording medium from the liquid ejection head 3, and once the liquid is ejected onto the intermediate transfer body (intermediate transfer drum 1007) to form an image, the image is recorded on the recording medium 2. This is a configuration for transferring. In the recording apparatus 1000, four single-color liquid ejection heads 3 respectively corresponding to four types of CMYK inks are arranged in an arc along the intermediate transfer drum 1007. As a result, full-color recording is performed on the intermediate transfer member, and the recorded image is appropriately dried on the intermediate transfer member and then transferred to the recording medium 2 conveyed by the paper conveying roller 1009 by the transfer unit 1008. Transcribed. The paper conveyance system of the second application example is a horizontal conveyance mainly intended for cut paper, whereas in this application example, it can also be applied to continuous paper supplied from a main body roll (not shown). In such a drum transport system, it is easy to transport the paper while applying a constant tension to the paper, so that there is little transport jam even at high speed recording. For this reason, the reliability of the apparatus is improved and it is suitable for commercial printing and the like. As in the first and second application examples, the supply system of the recording apparatus 1000, the buffer tank 1003, and the main tank 1006 are fluidly connected to each liquid ejection head 3. Each liquid discharge head 3 is electrically connected to an electric control unit that transmits power and a discharge control signal to the liquid discharge head 3.

(Explanation of the fourth circulation path)
Similar to the second application example, the first and second circulation paths shown in FIG. 2 or 3 are also applicable as the liquid circulation path between the tank of the recording apparatus 1000 and the liquid ejection head 3. However, the circulation path shown in FIG. 34 is preferable. The main difference from the second circulation path of FIG. 3 is that a bypass valve 1010 communicating with the flow paths of the first circulation pumps 1001 and 1002 and the second circulation pump 1004 is added. The bypass valve 1010 has a function (first function) of lowering the pressure on the upstream side of the bypass valve 1010 by opening the valve when a preset pressure is exceeded. Also, it has a function (second function) for opening and closing the valve at an arbitrary timing by a signal from the control board of the printing apparatus main body.

  By the first function, it is possible to suppress an excessive or excessive pressure from being applied to the flow path on the downstream side of the first circulation pumps 1001 and 1002 or the upstream side of the second circulation pump 1004. For example, when troubles occur in the functions of the first circulation pumps 1001 and 1002, an excessive flow rate or pressure may be applied to the liquid discharge head 3. As a result, liquid may leak from the discharge port of the liquid discharge head 3 or the joints in the liquid discharge head 3 may be broken. However, when a bypass valve is added to the first circulation pumps 1001 and 1002 as in this application example, even when excessive pressure is generated, the bypass valve 1010 is opened so that the liquid path is upstream of each circulation pump. Since this is opened, the above trouble can be suppressed.

  Further, due to the second function, when the circulation drive is stopped, all the bypass valves 1010 are promptly opened based on a control signal from the main body side after the first circulation pumps 1001 and 1002 and the second circulation pump 1004 are stopped. Thereby, the high negative pressure (for example, several to several tens kPa) in the downstream portion (between the negative pressure control unit 230 and the second circulation pump 1004) of the liquid discharge head 3 can be released in a short time. When a positive displacement pump such as a diaphragm pump is used as the circulation pump, a check valve is usually built in the pump. However, by opening the bypass valve, the pressure in the downstream portion of the liquid discharge head 3 can be released also from the downstream buffer tank 1003 side. Although the pressure release in the downstream portion of the liquid discharge head 3 can be performed only from the upstream side, there is a pressure loss in the upstream flow path of the liquid discharge head and in the liquid discharge head. For this reason, it takes a long time to release the pressure, and the pressure in the common flow path in the liquid discharge head 3 may drop transiently, possibly destroying the meniscus at the discharge port. By opening the bypass valve 1010 on the downstream side of the liquid discharge head 3, pressure release on the downstream side of the liquid discharge head is promoted, so that the risk of meniscus destruction of the discharge port is reduced.

(Description of liquid discharge head structure)
The structure of the liquid ejection head 3 according to the third application example of the present invention will be described. FIG. 35A is a perspective view of the liquid ejection head 3 according to this application example, and FIG. 35B is an exploded perspective view thereof. The liquid discharge head 3 includes 36 recording element substrates 10 arranged in a straight line (inline) in the longitudinal direction of the liquid discharge head 3, and is an ink jet page-wide recording head that performs recording with one color liquid. is there. Like the second application example, the liquid discharge head 3 includes a signal input terminal 91 and a power supply terminal 92, and a shield plate 132 that protects the longitudinal side surface of the head.

  FIG. 35B is a perspective exploded view of the liquid discharge head 3, and each component or unit constituting the liquid discharge head 3 is divided and displayed for each function (the shield plate 132 is not shown). The role of each unit and each member and the order of the liquid circulation in the liquid discharge head 3 are the same as in the second application example. The main differences from the second application example are the electric wiring board 90, the position of the negative pressure control unit 230, and the shape of the first flow path member. As in this application example, in the case of the liquid ejection head 3 having a length corresponding to a recording medium of B2 size, for example, the power consumption of the liquid ejection head 3 is large, so that eight electrical wiring boards 90 are provided. Each of the electrical wiring boards 90 is attached to each side surface of the long electrical wiring board support part 82 attached to the liquid discharge unit support part 81 by four.

  36A is a side view of the liquid discharge head 3 including the liquid discharge unit 300, the liquid supply unit 220, and the negative pressure control unit 230. FIG. 36B is a schematic view illustrating the flow of the liquid. ) Is a perspective view showing a cross section taken along line XXXVIc-XXXVIc in FIG. In order to facilitate understanding, some configurations are simplified.

  A liquid connection unit 111 and a filter 221 are provided in the liquid supply unit 220, and a negative pressure control unit 230 is integrally formed below the liquid supply unit 220. As a result, the distance in the height direction between the negative pressure control unit 230 and the recording element substrate 10 is shorter than that in the second application example. This configuration has the advantage that not only the number of flow path connection portions in the liquid supply unit 220 is reduced and the reliability against leakage of the recording liquid is improved, but also the number of parts and the number of assembly steps can be reduced.

  Further, since the water head difference between the negative pressure control unit 230 and the surface where the discharge port is formed becomes relatively small, the inclination angle of the liquid discharge head 3 as shown in FIG. 33 is different for each liquid discharge head. Therefore, the present invention can be suitably applied to various recording devices. This is because the difference in water and the like can be reduced, so that the negative pressure difference applied to the discharge ports of the respective recording element substrates can be reduced even when the plurality of liquid discharge heads 3 are used at different inclination angles. In addition, since the distance between the negative pressure control unit 230 and the recording element substrate 10 is reduced, the flow resistance therebetween is reduced, so that the pressure loss difference due to the change in the flow rate of the liquid is also reduced, so that more stable negative pressure control can be performed. .

  FIG. 36B is a schematic diagram showing the flow of the recording liquid inside the liquid ejection head 3. Compared with the circulation path shown in FIG. 34, the circuit is the same, but FIG. 36B shows the flow of liquid in each component of the actual liquid discharge head 3. A pair of common supply channel 211 and common recovery channel 212 extending in the longitudinal direction of the liquid discharge head 3 are provided in the long second channel member 60. The common supply channel 211 and the common recovery channel 212 are configured such that liquid flows in directions opposite to each other, and a filter 221 is provided on the upstream side of each channel, and foreign matter that enters from the connecting portion 111 or the like. Trap. As described above, the common supply channel 211 and the common recovery channel 212 are preferable in that the temperature gradient in the longitudinal direction in the liquid discharge head 3 is reduced by flowing the liquid in the opposite direction. In FIG. 34, the flows of the common supply channel 211 and the common recovery channel 212 are shown in the same direction for the sake of simplicity.

  Negative pressure control units 230 are connected to the downstream sides of the common supply channel 211 and the common recovery channel 212, respectively. Further, in the middle of the common supply channel 211, there are branches to the plurality of individual supply channels 213a, and in the middle of the common recovery channel 212, there are branches to the plurality of individual recovery channels 213b. The individual supply channel 213 a and the individual recovery channel 213 b are formed in the plurality of first channel members 50, and each individual channel is an opening 21 of the lid member 20 provided on the back surface of the recording element substrate 10. (See FIG. 19C).

  The negative pressure control unit 230 indicated by H and L in FIG. 36B is a unit having a high pressure side (H) and a low pressure side (L). Each negative pressure control unit 230 has a relatively high (H) and low (L) negative pressure, and is configured to control the pressure upstream of the negative pressure control unit 230. It is. The common supply flow path 211 is connected to the negative pressure control unit 230 (high pressure side), and the common recovery flow path 212 is connected to the negative pressure control unit 230 (low pressure side), whereby the common supply flow path 211 and the common recovery flow path are shared. A differential pressure is generated between the flow paths 212. Due to the differential pressure, the liquid sequentially passes from the common supply channel 211 to the individual supply channel 213a, the discharge port 13 (pressure chamber 23) in the recording element substrate 10, and the individual recovery channel 213b. It flows to.

  In this application example, each discharge module 200 includes the first flow path member 50, the recording element substrate 10, and the flexible wiring substrate 40. In the present embodiment, there is no support member 30 (FIG. 18) described in the second application example, and the recording element substrate 10 including the lid member 20 is directly bonded to the first flow path member 50. The common supply flow channel 211 provided in the second flow channel member is connected to the individual supply flow channel from the communication port 61 formed on the upper surface thereof through the individual communication port 53 formed on the lower surface of the first flow channel member 50. 213a. Thereafter, the liquid is recovered via the pressure chamber 23 to the common recovery channel 212 via the individual recovery channel 213b, the individual communication port 53, and the communication port 61 in this order.

  Here, unlike the second application example shown in FIG. 15, the individual communication port 53 on the lower surface (the surface on the second flow channel member 60 side) of the first flow channel member 50 is provided on the second flow channel member 50. The opening is sufficiently large with respect to the communication port 61 formed on the upper surface of the. With this configuration, even when the position is shifted when the discharge module 200 is mounted on the second flow path member 60, fluid communication is reliably performed between the first flow path member and the second flow member. Therefore, the yield at the time of manufacturing the head can be improved and the cost can be reduced.

  Note that the description of the application example does not limit the scope of the present invention. As an example, in this application example, the thermal method in which bubbles are generated by a heating element to discharge liquid has been described. However, the present invention is also applied to a liquid discharge head that employs a piezo method and other various liquid discharge methods. be able to.

  In this application example, the ink jet recording apparatus (recording apparatus) in which liquid such as ink is circulated between the tank and the liquid discharge head has been described, but other forms may be used. In another embodiment, for example, two tanks are provided upstream and downstream of the liquid discharge head without circulating ink, and the ink in the pressure chamber is caused to flow by flowing ink from one tank to the other tank. It may be.

  Further, in this application example, an example using a so-called line type head having a length corresponding to the width of the recording medium has been described. However, a so-called serial type liquid discharge head that performs recording while scanning the recording medium. The present invention can also be applied to. As the serial type liquid discharge head, for example, a configuration in which a recording element substrate for discharging black ink and a recording element substrate for discharging color ink are mounted one by one, but the present invention is not limited to this. That is, a mode in which a plurality of recording element substrates are arranged so that the discharge ports overlap in the discharge port array direction, and a short liquid discharge head shorter than the width of the recording medium is created, and the recording medium 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. Since the basic configuration of the present embodiment is the same as that of the first application example, only the characteristic configuration will be described below.

  FIG. 22A is a perspective view showing the liquid ejection module 200 of the recording apparatus 1000 in the present embodiment. The liquid ejection module 200 has a configuration in which the recording element substrate 10 and the flexible wiring substrate 40 are disposed on the support member 30. FIG. 22B is an exploded perspective view showing the liquid ejection module 200. The terminals 16 of the recording element substrate 10 and the terminals 41 of the flexible wiring substrate 40 are electrically connected by a gold wire or the like (not shown), and the electrical connection portion is covered with a sealant 110 for protection. The support member 30 is formed with a fluid communication port 31 that supplies ink ejected by the liquid ejection module 200 to the recording element substrate 10. The support member 30 preferably has a high flatness and can be bonded to the recording element substrate 10 with sufficiently high reliability. For example, alumina or a resin material is preferable as the material.

  FIGS. 23A to 23C are diagrams showing the structure of the recording element substrate 10. FIG. 23A shows an outline of the entire recording element substrate 10, and FIG. 23B is an enlarged view of a portion XXIIIb of FIG. 23A, and an ejection port forming member for easy explanation. The state which permeate | transmitted 12 is shown in figure. FIG.23 (c) is sectional drawing in XXIIIc-XXIIIc of Fig.23 (a). A plurality of ejection port arrays corresponding to the respective ink colors are formed on the ejection port forming member 12 of the recording element substrate 10. At the positions corresponding to the respective ejection openings 13 on the substrate 11 of the recording element substrate 10, recording elements 15, which are heat generating elements for foaming the liquid with thermal energy, are arranged. Hereinafter, the direction in which the discharge port array in which the plurality of discharge ports 13 are arranged is referred to as “discharge port array direction”. A pressure chamber 23 having a recording element 15 therein is defined in the substrate 11 by a partition wall 22. The recording element 15 is electrically connected to the terminal 16 in FIG. 23A by electric wiring (not shown) provided on the recording element substrate 10, and is connected from the control circuit of the recording apparatus 1000 via the flexible wiring substrate 40. The liquid is boiled by generating heat based on the input pulse signal. The liquid is discharged from the discharge port 13 by the force of foaming due to boiling.

  Further, a sheet-like lid member 20 (see FIG. 23C) is laminated on the back surface of the surface of the recording element substrate 10 where the discharge ports 13 are formed. A plurality of openings 21 (supply openings 21) communicating with 18 are provided. In the present embodiment, three openings 21 are provided in the lid member 20 with respect to one liquid supply path 18. Each opening 21 of the lid member 20 communicates with the plurality of liquid communication ports 31 in FIG. The lid member 20 constitutes a part of the wall of the liquid supply path 18 formed on the substrate 11 of the recording element substrate 10, and specifically has a function as a lid of the liquid supply path 18. Further, the lid member 20 is preferably one having sufficient corrosion resistance to the liquid, and high accuracy is required for the opening shape and opening position of the opening 21 from the viewpoint of preventing color mixing. 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 provide the opening 21 by a photolithography process. In addition, the lid member 20 converts the pitch of the flow path by the opening 21, and it is desirable that the thickness is thin in consideration of the pressure loss, and it is desirable that the lid member 20 is formed of a film-like member. Considering the above, the lid member 20 is preferably composed of a thin resin film member having photosensitivity.

  In the present embodiment, the ink in the pressure chamber is circulated to the outside. By adopting such a configuration, when recording is performed by the liquid discharge head 3, recording is not performed (discharged). No) Ink flow can be generated at the discharge port or pressure chamber. As a result, it is possible to suppress the thickening of the ink at that portion. Further, thickened ink and foreign matter in the ink can be discharged to the outside of the liquid ejection module 200. For this reason, the liquid discharge head 3 of the present embodiment can perform high-speed and high-quality recording.

  First, a configuration in which ink circulates in the ejection port of the present embodiment will be described. As shown in FIG. 23, a liquid supply path 18 extends on one side and a liquid recovery path 19 extends on the other side along each of the ejection port arrays 14a to 14j. That is, each discharge port array is configured to be sandwiched between the liquid supply path 18 and the liquid recovery path 19. The liquid supply path 18 and the liquid recovery path 19 communicate with the pressure chamber via a supply port 17a and a recovery port 17b, respectively. The liquid supply path 18, the liquid recovery path 19, the supply port 17 a, and the recovery port 17 b are formed in the Si substrate 11.

  In the present embodiment, three openings 21 (supply openings) for one liquid supply path 18 and two openings 21 (recovery openings) for one liquid recovery path 19 are the lid member 20. Is provided. Each opening 21 of the lid member 20 communicates with a plurality of liquid communication ports 31 (see FIG. 22B) of the support member 30. In the present invention, the present invention is not limited to this, and it is sufficient that at least one opening 21 is provided for each of the liquid supply path 18 and the liquid recovery path 19.

  Next, the flow of liquid in the recording element substrate 10 will be described. The recording element substrate 10 includes a substrate 11 formed of Si and a discharge port forming member 12 formed of a photosensitive resin, and a lid member 20 is bonded to the back surface of the substrate 11. In the present embodiment, the lid member 20 and the substrate 11 are joined to each other without an adhesive. A recording element 15 is formed on one surface side of the substrate 11, and grooves constituting a liquid supply path 19 and a liquid recovery path 18 extending along the ejection port array 14 are formed on the back surface side thereof. The lid member 20 is provided on the back surface, and each liquid path is configured by covering the groove. The liquid supply path 18 and the liquid recovery path 19 formed by the substrate 11 and the lid member 20 are connected to a common supply path and a common recovery path (not shown) in the flow path member 50 (see FIG. 6), respectively. Therefore, a differential pressure is generated between the liquid supply path 18 and the liquid recovery path 19. When the liquid is ejected from the plurality of ejection ports 13 of the liquid ejection head 3 and recording is performed, the liquid in the liquid supply path 18 is supplied to the supply port 17a and the pressure chamber by this differential pressure. 22 and flows to the liquid recovery path 19 via the recovery port 17b (arrow C in FIG. 23C). With this flow, in the ejection port 13 and the pressure chamber 22 where recording is paused, it is possible to collect the thickened ink, bubbles, foreign matters, and the like generated by evaporation from the ejection port 13 in the liquid recovery path 19. Further, it is possible to prevent the ink in the ejection port 13 and the pressure chamber 22 from being thickened. The liquid recovered in the liquid recovery path 19 is recovered outside the liquid ejection module 200 through the opening 21 (recovery opening) of the lid member 20 and the liquid communication port 31 of the support member 30, and finally supplied to the recording apparatus. Recovered to the route. That is, the liquid supplied from the recording apparatus main body to the liquid ejection module 200 flows and is supplied and recovered in the following order. The liquid first passes through the liquid communication port 31 provided in the support member 30, the opening (supply opening) 21 provided in the lid member 20, the liquid supply path 18 provided in the substrate 11, and the supply port 17 a in order. 23. Of the liquid supplied to the pressure chamber 23, the liquid that has not been discharged from the discharge port 13 is provided in the recovery port 17 b, the liquid recovery path 19, the opening (recovery opening) 21 provided in the lid member 20, and the support member 30. Then, the liquid flows through the liquid communication port 31 and flows out of the liquid discharge module 200.

  Thus, in the liquid discharge module 200 of the present embodiment, it is possible to suppress the thickening of the liquid in the vicinity of the pressure chamber 23 and the discharge port 13. As a result, ejection deviation and non-ejection can be suppressed, and as a result, high-quality recording can be performed.

  Here, the characteristic matters of the present invention will be described with reference to the drawings in comparison with a comparative example. FIG. 24A is a view showing the relationship between the ejection port array of the recording element substrate as a comparative example, the position of the opening of the lid member, and the corresponding recording density. In the comparative example, the opening 21 of the lid member is arranged at the same position in each discharge port row in the discharge port row direction. In such a configuration, since the negative pressure at the ejection ports on the same straight line in the recording medium conveyance direction (arrow β direction) of all of the ejection port arrays 14a to 14j is substantially the same, the ejection port with a low negative pressure. In the vicinity of the opening, the recording density is relatively high, and the recording density is relatively low at the discharge port having a high negative pressure. In other words, as shown in the graph of FIG. 24A, the positions where the recording density increases and the positions where the recording density decreases for each ejection port array are aligned, so that the density in the recording is emphasized on the recording medium, resulting in recording unevenness. It becomes easy to be visually recognized.

  Therefore, in the present invention, the arrangement of the opening 21 of the lid member 20 is as follows. FIG. 24B is a diagram showing the relationship between the ejection port array of the recording element substrate 10 and the position of the opening 21 of the lid member 20 and the corresponding recording density in the present embodiment. In the liquid ejection module 200 of the present embodiment, the center position (center of gravity position) of the opening 21 of the lid member 20 is a direction (recording medium conveyance direction) that is substantially orthogonal to the arrangement direction in which the ejection ports are arranged between the ejection port arrays 14. (Arrow β direction)) is arranged so as not to line up on the same straight line. Specifically, the center positions of the openings 21 are arranged on the same straight line that forms a predetermined angle with respect to a direction substantially orthogonal to the arrangement direction in which the discharge ports are arranged in the discharge port array. In this way, by making the recording density distribution different depending on the position of each of the ejection port arrays 14a to 14j, the density of the recording density is reduced, making it difficult to visually recognize. Therefore, it is possible to improve the recording quality when recording on the recording medium.

  In the present invention, it is not necessary that the centers of all the openings 21 are shifted on the straight line, and the center position of at least one opening 21 in the plurality of ejection port arrays is on the same straight line in the recording medium conveyance direction. An effect can be acquired by arranging so that it may not line up.

  Here, in the present embodiment, the flow of ink refill to the pressure chamber 23 that occurs after ink is ejected is stronger than the above-described flow that circulates in the pressure chamber, although for a short time. For this reason, the opening 21 has a supply opening 21 on the supply side and a recovery opening 21 on the recovery side, but the flow of ink refill to the pressure chamber 23 that occurs after the ink is ejected is circulated. Momentarily, it is generated from both the supply side and the collection side. At that time, the negative pressure at the discharge port near the opening 21 decreases, and the negative pressure at the discharge port increases as the distance from the opening 21 increases. Therefore, as shown in the recording density distribution of FIG. 24B, the recording density becomes higher near the opening 21 regardless of either the supply opening 21 or the recovery opening 21, and the recording density decreases as the distance from the opening 21 increases. Become. Therefore, the center position of the supply opening 21 of the discharge port array 14 and the center of the recovery opening 21 of the same discharge port array 14 are not aligned on the same straight line in the recording medium transport direction, so that The portion where the recording density is high can be dispersed. In order to achieve such an effect, it is preferable that the center positions of the supply side opening 21 and the collection side opening 21 are not arranged on the same straight line in the recording medium conveyance direction even between different ejection port arrays 14. desirable. In this case, it is more preferable that the center positions of all the openings 21 on the supply side and the recovery side are not aligned on the same straight line in the recording medium conveyance direction as shown in FIG.

  Note that the present invention can be applied to a structure without the lid member 20 by providing the support member 30 with the function of the lid member 20.

  As described above, in the plurality of ejection port arrays, the center (center of gravity) position of at least one opening is not aligned on the same straight line extending in the moving direction of the recording medium in relative movement with respect to the other opening center position. Place an opening in As a result, a liquid discharge module capable of suppressing the occurrence of recording unevenness and a liquid discharge head including the liquid discharge module can be realized.

(Second Embodiment)
The fourth embodiment of the present invention will be described below with reference to the drawings. Since the basic configuration of the present embodiment is the same as that of the first embodiment, only the characteristic configuration will be described below.

  FIG. 25A is a diagram illustrating the recording element substrate 400 of the present embodiment, FIG. 25B is an exploded perspective view of the liquid ejection module 500, and FIG. 25C is a liquid ejection module. FIG. 6 is a diagram illustrating a liquid discharge head 600 in which 50 are arranged.

  In the configuration of the first embodiment described above, the longest distance from the opening 21 to the discharge port 13 is different between the discharge port arrays. For example, in FIG. 23A, the distance between the discharge port 13 at the right end of the drawing in the discharge port row 14a and the opening 21 is compared with the distance between the discharge port 13 at the right end of the drawing in the discharge port row 14e and the opening 21. As can be seen, the discharge port array 14a is longer. In such a configuration, the negative pressure becomes large at the ejection port 13 far from the opening 21, so that when ink is supplied at a high speed, the ink supply may not be in time, resulting in non-ejection. As a result, there is a concern that the recording quality deteriorates.

  Therefore, in this embodiment, the maximum distance from the opening 21 of each discharge port array 14 to the discharge port 13 is configured to be substantially the same without changing the number of openings 21 corresponding to each discharge port array 14. . As shown in FIG. 25A, in the present embodiment, the center (center of gravity) of the opening 21 through which the same kind of liquid flows in each ejection port array 14 forms a predetermined angle α (α> 0) with respect to the recording medium conveyance direction. The recording element substrates are configured to be aligned on the same straight line, and the outer shape of the recording element substrate is a substantially parallelogram having sides forming a predetermined angle α with respect to the recording medium conveyance direction. The parallelogram in the present embodiment is a shape in which the angle formed by adjacent sides of the outer diameter of the recording element substrate 400 is not 90 degrees as shown in FIG. The outer shapes (sides) at both ends of the recording element substrate 400 in the ejection port array direction are substantially parallel to the ejection port array, and the other two sides have the same type of liquid flowing in the direction intersecting the ejection port array. It is substantially parallel to a line connecting the centers of the plurality of openings 21. Note that the same straight line having a predetermined angle with respect to the recording medium conveyance direction is substantially parallel to a side that is not parallel to the ejection port array of the recording element substrate 400.

  With such a structure, each discharge port array 14 can be configured such that the longest distance from the opening 21 to the discharge port is substantially equal. As described above, since the longest distance is substantially equal in each of the ejection port arrays 14, the ink does not flow through the supply flow path 18 for an extremely long distance, so that the pressure loss is reduced and the recording quality can be improved. Furthermore, when there are a plurality of openings 21 in the same supply flow path 18, at least the distance from the end of the discharge port array 14 to the opening 21 is shorter than the opening interval of the openings 21 of the same supply flow path 18 in the discharge port array direction. Good. By arranging the opening in such a manner, the ink does not flow through the supply flow path 18 for an extremely long distance, and the recording quality can be further improved.

  As described in the third embodiment, since ink is also supplied from the collection channel 19 side during ejection, not only the opening 21 of the supply channel 18 but also the opening 21 of the collection channel 19 is arranged in the same manner. It is desirable to do.

  Further, when the recording element substrate has a substantially parallelogram shape, the liquid ejection modules 200 can be arranged in-line in the longitudinal direction of the liquid ejection head 600 as shown in FIG. By using a line type liquid discharge head (page wide type liquid discharge head) in which the liquid discharge modules 200 are arranged in-line, higher-speed recording is possible. In that case, it is desirable to partially overlap the ejection ports of different ejection port arrays at the connecting portions of the liquid ejection modules 200 in order to improve the recording quality. As shown in FIG. 25C, in order to partially overlap the ejection ports of different ejection port arrays, the ejection port array 14 of each recording element substrate 10 is at a certain angle with respect to the longitudinal direction of the liquid ejection head 600. It is tilted. In such a line head configuration, since one-pass printing is often performed, the problem of the present invention is likely to appear remarkably, and the effect of the present invention is particularly easily obtained.

  Although the description has been made with the configuration in which many types of ink are supplied to one recording element substrate 10, the same effect can be obtained even in the configuration in which one type of ink is supplied. For example, in a liquid discharge head for recording at high speed for a commercial printing machine, one liquid discharge head may be arranged for one type of ink. However, a liquid discharge module of such a liquid discharge head may also be used. With such a configuration, the recording quality can be improved.

(Third embodiment)
Hereinafter, a third embodiment of the present invention will be described with reference to the drawings. Since the basic configuration of the present embodiment is the same as that of the first application example, only the characteristic configuration will be described below.

  FIGS. 26A to 26C are diagrams showing the structure of the recording element substrate 10. 26A shows an outline of the entire recording element substrate 10, FIG. 26B is an enlarged view of the XXVIb portion of FIG. 26A, and FIG. 26C is FIG. It is sectional drawing in XXVIc-XXVIc of a).

  In the present embodiment, the configuration of the flow path for supplying ink to the ejection port is different from the above-described embodiments. In each of the above-described embodiments, the configuration in which the flow path for supplying ink to the ejection port and the flow path for collecting ink from the ejection port are separated. However, in this embodiment, the liquid supply path 418 is not circulated. Ink is supplied from the nozzle to the ejection port. The liquid supply path 418 is a flow path provided in the recording element substrate 410 and extending in the discharge port array direction, and communicates with the discharge port 13 through the supply port 417a. As described above, according to the present invention, regardless of whether or not the circulation is performed, that is, whether or not the recovery opening 21 is present, the recording density becomes high near the opening 21 at the time of refilling. The farther from the recording density, the lower the recording density. Therefore, the present invention is also applicable to the liquid discharge head of the present embodiment that does not circulate.

  Hereinafter, the flow of the liquid in the liquid discharge module 200 will be described. Ink supplied from an ink supply source (not shown) first passes through the liquid communication port 31 (see FIG. 22B) formed in the support substrate 30 in the liquid ejection module 200, and then the lid member of the recording element substrate 410. The liquid flows into the liquid supply path 418 through the supply opening 21 of 420. At this time, in a general ink jet recording apparatus, four colors of ink of black, cyan, magenta, and yellow are used, and are supplied separately for each color. In the recording apparatus 1000 of the present embodiment, black has four rows, and each other color has two ejection port rows.

  The ink that has flowed into the liquid supply path 418 flows through the liquid supply path 418, passes through the supply port 417 a, flows into the common supply liquid chamber 24, and is distributed to the pressure chambers 23. The ink supplied to each pressure chamber 23 is boiled by the thermal energy generated by the recording element 15 and discharged from the discharge port 13, and recording is performed by the ink landing on a recording medium (not shown). By disposing the supply ports 417a on both sides of the discharge port array 14 as in the present embodiment, the supply after ink discharge is increased, and higher-speed recording is possible. It should be noted that the present invention can be applied even if 417a is arranged only on one side.

  Here, the features of the present invention will be described. In the present embodiment, the arrangement of the opening of the lid member is as follows. FIG. 27A is a diagram showing the relationship between the ejection port array of the recording element substrate 410 and the opening position of the lid member 420 and the corresponding recording density in the present embodiment. In the present embodiment, the opening 21 is arranged so that the center of the opening 21 of the lid member 420 is not on the same straight line in the conveyance direction (arrow β direction) of the recording medium. With this configuration, the discharge port position in the discharge port row direction where the negative pressure increases for each discharge port row is different from the discharge port position in the discharge port row direction where the negative pressure decreases. In the outlet row, the position where the recording density in the ejection port row direction is thicker and the position where the recording density is thinner are different. As a result, on the recording medium, the portion where the recording density is high and the portion where the recording density is thin are dispersed for each ejection port array, thereby reducing the shading on the recording medium, making it difficult to see and improving the recording quality. be able to.

  In the present embodiment, the center positions of the openings 21 of all the lid members 420 are not arranged on the same straight line in the recording medium conveyance direction. However, the present invention is not limited to this. In other words, the effect of the present invention can be achieved if the at least one opening 21 is not arranged on the same straight line in the recording medium conveyance direction with respect to the openings 21 of the other ejection port arrays.

  Furthermore, there is a further effect when it is applied to the discharge port arrays 14 of the same color, and a larger effect is produced when the method is applied to many discharge port arrays 14. Therefore, it is desirable to configure the openings 21 of the discharge port arrays 14 as much as possible so that they are not aligned on the same straight line in the recording medium conveyance direction. It is most desirable to make the center position different in the discharge port array direction.

  In each of the above embodiments, the phrase “center of the opening 21” is used, but this can be defined as the center of gravity of the shape of the opening 21. That is, FIG. 27B illustrates openings having various shapes when viewed from the lid member 420 side. As shown in the figure, the center of the opening 21 is the intersection of diagonal lines if the opening shape is a parallelogram, the center of a circle if it is circular, and the intersection of two symmetrical axes of symmetry if it is a long circle.

3 Liquid discharge head 10 Recording element substrate 14 Discharge port array 20 Lid member 21 Opening 200 Liquid discharge module

Claims (20)

In a liquid ejection module used for a page-wide liquid ejection head that ejects liquid from an ejection port to a relatively moving recording medium,
Liquid is supplied to each of the first and second discharge port arrays and the first and second discharge port arrays in which discharge ports for discharging the liquid are arranged in a direction intersecting the relative movement direction. A recording element substrate comprising: first and second liquid supply paths extending in the intersecting direction;
First and second openings communicating with each of the first and second liquid supply paths for supplying liquid to each of the first and second liquid supply paths;
The liquid discharge module according to claim 1, wherein a center of gravity of the first opening and a center of gravity of the second opening are deviated from a straight line extending in the relative movement direction. A support member that supports the recording element substrate and includes a communication port that supplies liquid to the first and second openings;
A wiring board capable of supplying electrical energy to an ejection energy generating element provided on the recording element substrate;
The liquid discharge module according to claim 1, further comprising:   3. The liquid ejection module according to claim 1, wherein a plurality of the first and second openings are provided with respect to the first and second liquid supply paths, respectively. A discharge port for discharging the liquid extends in the intersecting direction, supplying a liquid to the third discharge port array, a third discharge port array arranged in a direction intersecting the relative movement direction. A third liquid supply path that exists, and a third opening for supplying liquid to the third liquid supply path,
The first, second, and third openings are provided such that their respective centers of gravity are positioned on straight lines that are inclined with respect to a straight line that extends in the direction of relative movement. The liquid ejection module according to any one of claims 1 to 3.   The recording element substrate includes: an ejection energy generating element that generates energy used to eject liquid; a pressure chamber that includes the ejection energy generating element; and the liquid chamber for recovering the liquid from the pressure chamber. 5. The liquid ejection module according to claim 1, further comprising a liquid recovery path extending in an intersecting direction.   The liquid discharge module according to claim 5, further comprising a recovery opening for recovering the liquid from the liquid recovery path. The first and second liquid supply paths are provided on the surface of the recording element substrate opposite to the side on which the discharge port is provided,
The liquid according to any one of claims 1 to 6, wherein the first and second openings are provided in a film member provided on the opposite surface of the recording element substrate. Discharge module.   The liquid discharge module according to claim 1, wherein the same kind of liquid is supplied to the first and second liquid supply paths.   The length of the longest liquid path among the plurality of discharge ports supplied with liquid from the first opening, and the length of the longest liquid path among the plurality of discharge ports supplied with liquid from the second opening; The liquid discharge module according to claim 1, wherein the two are equal to each other.   The liquid ejection module according to claim 1, wherein an outer shape of the recording element substrate is a substantially parallelogram.   The recording element substrate includes a plurality of supply ports for supplying liquid from the first liquid supply path to the discharge port, and the plurality of supply ports extend in a thickness direction of the recording element substrate. The liquid ejection module according to claim 1, wherein the liquid ejection module is a liquid ejection module. The recording element substrate includes a discharge energy generating element that generates energy used to discharge a liquid, and a pressure chamber that includes the discharge energy generating element therein.
The liquid discharge module according to any one of claims 1 to 11, wherein the liquid in the pressure chamber is circulated between the outside of the pressure chamber. In a page-wide type liquid discharge head that discharges liquid from a discharge port to a relatively moving recording medium,
Liquid is supplied to each of the first and second discharge port arrays and the first and second discharge port arrays in which discharge ports for discharging the liquid are arranged in a direction intersecting the relative movement direction. A recording element substrate comprising: first and second liquid supply paths extending in the intersecting direction;
A first opening and a second opening communicating with each of the first and second liquid supply paths for supplying a liquid to each of the first and second liquid supply paths; And a lid member constituting a part of the second liquid supply path,
The center of gravity of the first opening and the center of gravity of the second opening are deviated from a straight line extending in the relative movement direction.   The liquid discharge head according to claim 13, wherein the lid member is a photosensitive film member. The recording element substrate supplies a liquid to a third ejection port array in which ejection ports for ejecting a liquid are arranged in a direction intersecting the direction of the relative movement, and the third ejection port array, A third liquid supply path extending in the intersecting direction,
The lid member includes a third opening for supplying a liquid to the third liquid supply path;
The first, second, and third openings are provided such that their respective centers of gravity are positioned on straight lines that are inclined with respect to a straight line that extends in the direction of relative movement. Item 15. The liquid discharge head according to Item 13 or 14. The recording element substrate includes: an ejection energy generating element that generates energy used to eject liquid; a pressure chamber that includes the ejection energy generating element; and the liquid chamber for recovering the liquid from the pressure chamber. A liquid recovery path extending in the intersecting direction,
The liquid discharge head according to claim 13, wherein the lid member includes a recovery opening for recovering the liquid from the liquid recovery path. A support member for supporting the plurality of recording element substrates;
The liquid discharge head according to claim 13, wherein the plurality of recording element substrates are linearly arranged in the intersecting direction. The recording element substrate includes a discharge energy generating element that generates energy used to discharge a liquid, and a pressure chamber that includes the discharge energy generating element therein.
18. The liquid ejection head according to claim 13, wherein the liquid in the pressure chamber is circulated between the pressure chamber and the outside of the pressure chamber. A liquid ejection head having a plurality of recording element substrates that eject liquid from ejection ports to a relatively moving recording medium;
The discharge port communicates with a flow path extending in a direction intersecting the moving direction provided in the recording element substrate;
The plurality of discharge ports form a plurality of discharge port arrays that are arranged along the flow path,
The recording element substrate provided with a plurality of the ejection port arrays includes the flow path corresponding to each ejection port array, and a plurality of openings for supplying liquid to the flow path,
The barycentric position of at least one of the openings is shifted from the same straight line extending in the moving direction of the recording medium in relative movement with respect to the barycentric position of the openings included in the other ejection port arrays. A liquid discharge head.   An energy generating element that generates energy used for discharging the liquid, a pressure chamber having the energy generating element therein, a supply channel for supplying the liquid to the pressure chamber, and a liquid from the pressure chamber A recovery channel for recovering liquid, a supply port for supplying liquid from the supply channel to the pressure chamber, and a recovery port for recovering liquid from the pressure chamber to the recovery channel; The liquid discharge head according to claim 19, wherein the liquid in the pressure chamber is circulated to the outside through the supply channel and the recovery channel.