Printed element substrate

Abstract

A print element substrate includes: a first heating resistor element row arranged in a row; a second heating resistor element row arranged in a row parallel to the first heating resistor element row; a first drive element row arranged in a row to drive a plurality of first heating resistor elements, the plurality of drive elements being arranged to drive the plurality of heating resistor elements; and a second drive element row arranged in a row parallel to the first drive element row to drive a plurality of second heating resistor elements, the plurality of second drive elements being different from the plurality of first drive elements. Respective distances between centers of gravity of the first drive elements and the second drive elements are smaller than respective distances between centers of gravity of the first heating resistor elements and the second heating resistor elements.

Description

Technical Field

[0001] This disclosure relates to techniques for arranging driving elements on a printed element substrate. Background Technology

[0002] Conventionally, circulating liquid jetting devices configured to circulate ink within a liquid jet head are known. Japanese Patent Application Publication No. 2020-104493 (hereinafter referred to as PTL 1) discloses a configuration for circulating liquid jetting devices, in which a jetting energy generating element configured to jet ink and a circulating energy generating element configured to circulate the ink are provided. Furthermore, a drive element is provided to drive each of the jetting energy generating element and the circulating energy generating element. Summary of the Invention

[0003] The objective of this disclosure is to enable the proper arrangement of drive elements on a printed element substrate.

[0004] A printed element substrate according to one aspect of this disclosure includes: a first row of heating resistor elements, the first row of heating resistor elements including a plurality of first heating resistor elements arranged in a row of a plurality of heating resistor elements; a second row of heating resistor elements including a plurality of second heating resistor elements arranged in a row parallel to the first row of heating resistor elements, the plurality of second heating resistor elements being different from the plurality of first heating resistor elements; and a first row of driving elements including a plurality of first driving elements arranged in a row of a plurality of driving elements for driving the plurality of first heating resistor elements. The first drive element row includes a plurality of second drive elements arranged in a row parallel to the first drive element row to drive a plurality of second heating resistor elements. The plurality of second drive elements are different from the plurality of first drive elements, wherein the distance between the centroids of two adjacent first drive elements in the plurality of first drive elements is less than the distance between the centroids of two adjacent first heating resistor elements in the plurality of first heating resistor elements, and the distance between the centroids of two adjacent second drive elements in the plurality of second drive elements is less than the distance between the centroids of two adjacent second heating resistor elements in the plurality of second heating resistor elements.

[0005] The features of this disclosure will become apparent from the following description of embodiments with reference to the accompanying drawings. The following description of the embodiments is by way of example. Attached Figure Description

[0006] Figure 1AThis is a schematic perspective view illustrating a liquid jetting device in which a cartridge, serving as a liquid reservoir, is disposed outside the liquid jetting head. Figure 1B This is a schematic perspective view of a liquid jetting device in which the auxiliary ink cartridge is positioned directly above the liquid jetting head.

[0007] Figure 2A yes Figure 1A and Figure 1B Exploded perspective view of the liquid jet head in each of them. Figure 2B This diagram illustrates the case where four colors can be ejected from a single liquid jet chip. Figure 2C This is an illustration of a case where two colors can be ejected from a single liquid jet chip. Figure 2D This is an illustration of a case where the amount of color that can be sprayed by a liquid jet chip is one color.

[0008] Figure 3A This is a plan view taken from the direction of the liquid droplets ejected from the nozzle of a single injection unit. Figure 3B yes Figure 3A Cross-sectional view of IIIB-IIIB Figure 3C yes Figure 3A The cross-sectional view of IIIB-IIIB' and the internal configuration of the substrate. Figure 3B Different cross-sectional views of the internal configuration of the substrate, and Figure 3D It is a diagram illustrating the inflow of ink when the first energy generating element is driven.

[0009] Figure 4A yes Figure 3A The cross-sectional view of the individual injection unit (IIIB-IIIB) is a cross-sectional view describing the generation and growth process of bubble B generated by heating the ink using a second energy generating element and causing film boiling of the ink. Figure 4B yes Figure 3A The cross-sectional view of the individual injection unit IIIB-IIIB' is a cross-sectional view describing the contraction process of bubble B generated by heating the ink using a second energy generating element and causing the ink to boil in a film state. Figure 4C yes Figure 3A The cross-sectional view of the individual injection unit IIIB-IIIB' is a cross-sectional view describing the process after the bubble B generated by heating the ink using a second energy generating element and causing the ink to boil in a film state disappears.

[0010] Figure 5A This is a diagram illustrating a state where the circulation of ink has temporarily stopped. Figure 5B This is an example that follows through Figure 5AThe diagram illustrates the state after the second energy-generating element is driven to generate the circulating flow of ink, following the initial state. Figure 5C This illustrates the circulating flow of ink. Figure 5B A diagram showing the state that has temporarily stopped after the previous state, and Figure 5D This is an example that follows through Figure 5C The diagram shows the state after the second energy generating element is driven to generate the circulating flow of ink in the middle state.

[0011] Figure 6A This is a diagram illustrating a state where the circulation of ink has temporarily stopped. Figure 6B This is an example that follows through Figure 6A The diagram illustrates the state after the second energy-generating element is driven to generate the circulating flow of ink, following the initial state. Figure 6C This illustrates the circulating flow of ink. Figure 6B A diagram showing the state that has temporarily stopped after the previous state, and Figure 6D This is an example that follows through Figure 6C The diagram shows the state after the second energy generating element is driven to generate the circulating flow of ink in the middle state.

[0012] Figure 7A This is a plan view taken from the direction in which the droplets are ejected from the nozzle. Figure 7B yes Figure 7A The cross-sectional view of VIIB-VIIB, and Figure 7C yes Figure 7A An enlarged schematic diagram of a single flow path in the image.

[0013] Figure 8A This is a plan view taken from the direction in which the droplets are ejected from the nozzle. Figure 8B yes Figure 8A Cross-sectional views of VIIIB-VIIIB, and Figure 8C yes Figure 8A Cross-sectional views of VIIIB-VIIIB and the internal configuration of the substrate. Figure 8B Different cross-sectional views of the internal configuration of the substrate.

[0014] Figure 9A This is a plan view taken from the direction in which the droplets are ejected from the nozzle. Figure 9B yes Figure 9A The cross-sectional view of IXB-IXB, and Figure 9C yes Figure 9A The IXB-IXB cross-sectional view shows the internal configuration of the substrate. Figure 9B Different cross-sectional views of the internal configuration of the substrate.

[0015] Figure 10This is a diagram illustrating an example of the circuit configuration of a printed element substrate according to this embodiment.

[0016] Figure 11 This is a diagram illustrating an example arrangement of the heater and drive element according to the first case of this embodiment.

[0017] Figure 12 This is a diagram illustrating an example arrangement of the heater and drive element according to the second case of this embodiment.

[0018] Figure 13 This is a diagram illustrating an example of the arrangement of the heater and drive element according to a third case of this embodiment.

[0019] Figure 14 This is a diagram illustrating an example of the arrangement of the heater and drive element according to the fourth case of this embodiment.

[0020] Figure 15 This is a diagram illustrating an example of the arrangement of the heater and drive element in the first comparative example.

[0021] Figure 16 This is a diagram illustrating an example of the arrangement of the heater and drive element in the second comparative example.

[0022] Figure 17 This is a diagram illustrating an enlarged example of the driving element in the first case.

[0023] Figure 18 This is an example of having a ratio Figure 17 A magnified example of a driving element with few grounding wires is shown in the diagram.

[0024] Figure 19 This is a diagram illustrating an enlarged example of the driving element in the second case.

[0025] Figure 20 This is an example of having a ratio Figure 19 A magnified example of a driving element with few grounding wires is shown in the diagram.

[0026] Figure 21 This is a diagram illustrating an enlarged example of the driving element in the second comparative example.

[0027] Figure 22 This is an example along Figures 17 to 20 A diagram showing the cross-sectional structure taken from the XXII-XXII line.

[0028] Figure 23 This is a diagram illustrating another circuit configuration example of a printed element substrate according to this embodiment. Detailed Implementation

[0029] Preferred embodiments of the present disclosure are described in detail below with reference to the accompanying drawings. It should be noted that the following embodiments are not intended to limit the scope of the present disclosure, and not all combinations of the features described in the following embodiments are necessary for the means to solve the problems of the present disclosure. It should be noted that the same constituent elements are indicated by the same reference numerals.

[0030] (Overview)

[0031] Conventionally, liquid ejector heads have the function of circulating ink to expel air bubbles in the ink flow path and suppressing ink thickening near the ejector orifice. Liquid ejection devices equipped with liquid ejector heads having the functions described above are already known as circulating liquid ejection devices. Furthermore, the method of using differential pressure (hereinafter also referred to as differential pressure method) to circulate ink is well known. In the differential pressure method, a pressure adjusting mechanism is used to increase the pressure in the ejector orifice on the ink supply side (inner side) compared to the pressure in the ejector orifice on the ink collection side (outer side). In this way, ink is allowed to flow from the inner side to the outer side. Furthermore, to circulate the ink, it is preferable to return the ink flowing to the outer side to the inner side. Therefore, a pump is provided. It should be noted that there is a configuration in which the pump is located outside the liquid ejector head of the liquid ejection device body so that the ink circulates between the liquid ejector head and the liquid ejection device body. Alternatively, there is another configuration in which the pump is located inside the liquid ejector head so that the ink circulates within the liquid ejector head. However, in the differential pressure method, the main body of the liquid injection device and the liquid injection head may be relatively large due to the presence of a pressure adjustment mechanism and a pump.

[0032] Therefore, methods other than differential pressure methods for ink circulation have also been considered. Specifically, there is a configuration in which a circulating flow path is provided in communication with the jet orifice, and an energy generating element (hereinafter referred to as a circulating energy generating element), which is different from the energy generating element configured to jet ink (hereinafter also referred to as the jet energy generating element), is provided in the circulating flow path. With this configuration, the ink can be circulated in the circulating flow path by driving the circulating energy generating element.

[0033] Incidentally, the configuration of arranging rows of jet energy generating elements and rows of circulating energy generating elements in parallel is already known. Using this configuration, a pair of circulating energy generating elements are mounted for each jet energy generating element. Therefore, the drive element and grounding wire are manufactured to be electrically connected to each of the jet energy generating element and the circulating energy generating element. That is, the drive element for each of the jet energy generating element and the circulating energy generating element is disposed on the printing element substrate, and according to the inventors' considerations, there have been cases where the drive element cannot be properly arranged in the printing element substrate. Furthermore, when the printing element substrate is formed by an inexpensive manufacturing process, it is not preferable to provide an electrical connection layer as another layer besides the conductive layer for extracting the electrodes of the drive element. That is, in an inexpensive manufacturing process, it is preferable to form the conductive layer and the connection layer from the same layer and in the same manufacturing step. Furthermore, when the magnitudes of the drive current of the jet drive element and the circulating drive element are different from each other, drive elements arranged in a row with the same shape (that is, with the same current driving capability) receive excessive quality and are therefore not preferred. Specifically, when the cyclic drive element and the jet drive element are formed with the same size, although the drive current of the cyclic drive element is less than that of the jet drive element, the substrate area of ​​the printed element is increased due to the excessive element size of the cyclic drive element, and the cost may be higher.

[0034] Therefore, the printed element substrate of this disclosure includes a first row of heating resistor elements, a second row of heating resistor elements, a first row of driving elements, and a second row of driving elements. In the first row of heating resistor elements, a plurality of first heating resistor elements are arranged in a row. The second row of heating resistor elements is arranged parallel to the first row of heating resistor elements, and a plurality of second heating resistor elements, different from the plurality of first heating resistor elements, are arranged in a row. In the first row of driving elements, a plurality of first driving elements, arranged to drive the plurality of heating resistor elements, are arranged in a row to drive the plurality of first heating resistor elements. The second row of driving elements is arranged parallel to the first row of driving elements, and a plurality of second driving elements, different from the plurality of first driving elements, are arranged in a row to drive the plurality of second heating resistor elements. The distance between the centers of gravity of two adjacent first driving elements in the corresponding plurality of first driving elements is less than the distance between the centers of gravity of two adjacent first heating resistor elements in the corresponding plurality of first heating resistor elements. Furthermore, the distance between the centers of gravity of two adjacent second driving elements in the corresponding plurality of second driving elements is less than the distance between the centers of gravity of two adjacent second heating resistor elements in the corresponding plurality of second heating resistor elements. As described above, the additional space created between the driving elements allows for the arrangement of wiring between them. Therefore, according to the printable element substrate of this disclosure, the driving elements can be appropriately arranged on the printable element substrate.

[0035] Specifically, two rows of drive elements with different element sizes are arranged parallel to each other in two rows, and in each row, the units of the drive elements are arranged adjacent to each other, with each unit comprising two or more drive elements adjacent to each other. Both grounding wires and electrical connection wires can be arranged in the area created between the units of the drive elements. Therefore, the conductive layer and wiring layer in the drive elements can be wired on the same layer.

[0036] <Liquid Jetting Equipment 50>

[0037] Figure 1A and Figure 1B This is a diagram illustrating an example of the overall configuration of a liquid jetting device 50. Figure 1A This is a perspective view schematically illustrating a liquid jetting device 50, in which a cartridge 2, serving as a liquid reservoir, is disposed outside the liquid jetting head 1. Figure 1B This is a schematic perspective view illustrating a liquid jetting device 50, in which the secondary ink cartridge 54 is positioned directly above the liquid jetting head 1. First, a description... Figure 1A and Figure 1B The common parts between them.

[0038] The liquid jetting apparatus 50 includes a liquid jetting head 1 and transport rollers 55, 56, 57, and 58. The liquid jetting head 1 can scan in a direction X that intersects the transport direction Y of the target medium P. The liquid jetting head 1 is mounted on a carriage 60. The liquid jetting head 1 is fixed and supported on the carriage 60 by a positioning unit (not illustrated) and electrical contacts provided to the carriage 60. The carriage 60 moves reciprocally along a guide shaft 51 in the main scanning direction (also referred to as direction X). Therefore, the liquid jetting head 1 performs printing on the target medium P by jetting ink while moving along the main scanning direction together with the carriage 60. The transport rollers 55, 56, 57, and 58 transport the target medium P in a secondary scanning direction (also referred to as the transport direction Y) that intersects (orthogonal in this embodiment) the main scanning direction. That is, the liquid jetting apparatus 50 forms a serial inkjet liquid jetting apparatus by jetting liquid from the liquid jetting head 1 onto the target medium P being transported along the transport direction Y while the liquid jetting head 1 scans along direction X. It should be noted that the application of this disclosure is not limited to serial inkjet liquid ejection equipment. This disclosure also applies to a page-width inkjet liquid ejection equipment that uses a longer lead (page-width head) in the page-width direction of the target medium P to eject liquid onto the target medium P being transported along the transport direction Y. It should be noted that in Figure 1A and Figure 1B In this context, direction Z indicates the vertical direction. That is, direction Z is the direction that intersects (orthogonal in this embodiment) the XY plane identified by direction X and transport direction Y.

[0039] The liquid ejector head 1 can eject four types of ink: black (K), cyan (C), magenta (M), and yellow (Y). The liquid ejector head 1 can eject full-color images using these four types of ink. It should be noted that the inks that can be ejected from the liquid ejector head 1 are not limited to the four types described above. For example, this disclosure also applies to liquid ejector heads 1 that eject another type of ink (such as a specific color ink). That is, the type and quantity of ink ejected from the liquid ejector head 1 are not limited.

[0040] Next, the description Figure 1A and Figure 1B The different parts between them. In Figure 1A In this configuration, a secondary ink cartridge 54 is mounted on the liquid ejector head 1. Four ink supply lines (liquid communication paths) 59 are attached to the secondary ink cartridge 54. Furthermore, the liquid ejector device 50 includes an ink cartridge 2 and an external pump 71. The ink cartridge 2 stores ink. The ink stored in the ink cartridge 2 is supplied to the secondary ink cartridge 54 via the four ink supply lines 59 by the driving force of the external pump 71. On the other hand, in... Figure 1B In this configuration, the secondary ink cartridge 54 is positioned directly above the liquid ejector head 1. Figure 1B In, with Figure 1A The difference is that, since the ink cartridge 2 is not located outside the liquid ejector head 1, it does not have four ink supply tubes 59 attached, and it does not have an external pump 71. It should be noted that... Figure 1A and Figure 1B In either of these configurations, the liquid injection head 1 may be integrally disposed with the sub-ink cartridge 54 and may be configured to be detachable from or attachable to the carriage 60. Alternatively, the sub-ink cartridge 54 may be integrally disposed with the carriage 60, and only the sub-ink cartridge 54 may be configured to be detachable or attachable. In the following description, the term "sub-ink cartridge 1" is used. Figure 1A The configuration in the document provides the description.

[0041] <Basic Configuration of Liquid Jet Head 1>

[0042] Figure 2 is a diagram illustrating a basic configuration example of the liquid jet head 1 in Figure 1. Figure 2A This is an exploded perspective view of the liquid jet head 1 in Figure 1. Figure 2B , Figure 2C and Figure 2D This is an example Figure 2A A diagram illustrating an example of the liquid ejection chip 3. The liquid ejection head 1 includes a storage section 53, a sub-ink cartridge 54, and the liquid ejection chip 3. The sub-ink cartridge 54 temporarily stores ink from the liquid ejection head 1. The sub-ink cartridge 54 is stored in the storage section 53. The liquid ejection chip 3 is positioned at the bottom of the storage section 53, and details will be described later. The liquid ejection chip 3 ejects ink supplied from the sub-ink cartridge 54 onto the target medium P.

[0043] Note that, although not illustrated, the liquid connector insertion port is located within the wall surface of the storage section 53. (Set to...) Figure 1A The liquid connector at the end of the ink supply tube 59 is inserted into the liquid connector insertion port and is liquid-tightly connected. With this configuration, an ink supply path from the ink cartridge 2 to the liquid ejector head 1 is formed by means of an external pump 71. In this embodiment, four types of ink are used. Therefore, four groups are provided for each ink, each group including the ink cartridge 2, the external pump 71, the ink supply tube 59, and the auxiliary ink cartridge 54. Thus, four ink supply paths corresponding to the ink are independently formed. Therefore, in this embodiment, the liquid ejector device 50 includes an ink supply system in which ink is supplied from the ink cartridge 2 disposed outside the liquid ejector head 1.

[0044] A first support member 4 and a second support member 7 are disposed between the storage portion 53 and the liquid ejection chip 3. An electrical connection member 5 is disposed below the liquid ejection chip 3. Specifically, an ink supply port and an ink collection port are disposed in the first support member 4. An opening is disposed in the second support member 7. The liquid ejection chip 3 is bonded and fixed to the first support member 4. The first support member 4 is bonded and fixed to the second support member 7. The second support member 7 holds the electrical connection member 5 in an electrical connection with the liquid ejection chip 3. The electrical connection member 5 applies electrical signals for ejecting ink and for circulating ink to the liquid ejection chip 3.

[0045] It should be noted that in this embodiment, the liquid jetting device 50 does not include an ink collection system for collecting ink from the liquid jetting head 1 into the ink cartridge 2. Therefore, the liquid jetting head 1 is provided with a liquid connector insertion port for connecting a liquid connector to the ink supply tube 59, but is not provided with a connector insertion port for connecting a tube for collecting ink into the ink cartridge 2.

[0046] Figure 2B This example illustrates a case where the liquid jet chip 3 is formed from a single chip corresponding to four colors. That is, Figure 2B An example is illustrated where four colors can be ejected by a liquid jet chip 3. The liquid jet chip 3 includes multiple jetting orifices and pads for electrical implementation. The four colors are, for example, black, cyan, magenta, and yellow, and rows are formed for each color. The rows are formed along the transport direction Y and arranged at intervals along the direction X. Each row includes multiple jetting orifices. The multiple jetting orifices are arranged at equal intervals along the Y direction. The jetting orifices in each row may not be arranged at intervals in the X direction, and may be arranged in a single row along the Y direction. Alternatively, only black may be arranged in two rows, while the other three colors may be arranged in three rows, and the four colors may be arranged in a total of five rows. Note that... Figure 2A The liquid jetting chip 3 in the example illustrates a configuration where each chip has four colors. That is to say, Figure 2A Three examples of liquid jetting chips are shown in the figure. Figure 2B Examples of situations in [the context].

[0047] Figure 2C This example illustrates a case where the liquid jet chip 3 is formed from a single chip corresponding to two colors. In this case, two chips are used. That is, Figure 2C An example is given where the number of colors that can be sprayed by a single liquid spraying chip 3 is two. When the liquid spraying chip 3 is implemented on a liquid spraying head 1, two liquid spraying chips 3 can be implemented on one liquid spraying head 1, or two liquid spraying heads 1 can be prepared, each of which includes a liquid spraying chip 3 implemented thereon.

[0048] Figure 2D This example illustrates a case where the liquid jet chip 3 is formed from one chip corresponding to a single color. In this case, four chips are used. That is, Figure 2D An example is given where the number of colors that can be sprayed by a single liquid spraying chip 3 is one color. When the liquid spraying chip 3 is implemented on a liquid spraying head 1, four liquid spraying chips 3 can be implemented on one liquid spraying head 1, or four liquid spraying heads 1 can be prepared, each of which includes a liquid spraying chip 3 implemented thereon.

[0049] It should be noted that the case in which multiple liquid injection chips 3 are implemented on a single liquid injection head 1 is assumed to be... Figure 2C and Figure 2D In this case, the chip length of each liquid jet chip 3 can be different. Furthermore, there is no particular limitation on the number of colors of the liquid jet chip 3, and various combinations of the number of colors can be applied. For example, although an example for... Figure 2A The liquid jet chip 3 in the example has four colors, but the liquid jet chip 3 can have more than four colors.

[0050] <Independent flow path; straight shape>

[0051] The liquid injection head 1 includes multiple individual injection units, each including a separate flow path. The liquid injection head 1 also includes a supply flow path for supplying liquid to the separate flow path of each individual injection unit. Figure 3 is a diagram illustrating the location near the injection orifice 11 of an individual injection unit, which includes a separate flow path 23 with a straight shape. Figure 3A This is a plan view taken from the direction of the liquid droplets ejected from the ejection orifice 11 of a single ejection unit. Figure 3B yes Figure 3A Cross-sectional view of IIIB-IIIB. Figure 3C yes Figure 3A The cross-sectional view of IIIB-IIIB', and Figure 3B These are cross-sectional views showing different internal configurations of the substrate 18.

[0052] The individual injection unit includes an injection orifice 11, a pressure chamber 12, a first energy generating element 14 (also called an injection energy generating element 14), and a second energy generating element 24 (also called a circulating energy generating element 24).

[0053] The pressure chamber 12 is formed for each injection orifice 11 by a partition 21 separating the space between the substrate 18 and the orifice plate 19. The injection orifice 11 is an opening formed in a portion of the orifice plate 19. The meniscus of ink flowing through the pressure chamber 12 is formed in the injection orifice 11, forming an injection orifice interface that serves as the interface between the ink and the atmosphere. The injection orifice 11 ejects liquid.

[0054] A separate flow path 23 extends along a second direction that intersects (orthogonally in this embodiment) the direction in which the injection orifices 11 are arranged to form a row (a first direction). The separate flow path 23 includes a pressure chamber 12, an inlet port (upstream) side connecting flow path 13, and an outlet port (downstream) side connecting flow path. The inlet port side connecting flow path 13 communicates with one end portion of the pressure chamber 12. The outlet port side connecting flow path communicates with the other end portion of the pressure chamber 12.

[0055] A first supply opening 22 is provided on one end side of the separate flow path 23. The first supply opening 22 is an opening portion that passes through the interior of the substrate 18 and extends upstream of the separate flow path 23 via a common flow path (not illustrated). A second supply opening 32 is provided on the other end side of the separate flow path 23. The second supply opening 32 is an opening portion that passes through the interior of the substrate 18 and extends downstream of the separate flow path 23 via a common flow path (not illustrated). Liquid is supplied to the separate flow path 23 via the first supply opening 22 and the second supply opening 32.

[0056] In the substrate 18, the first energy generating element 14 is formed closer to the second supply opening 32 than the first supply opening 22. The first energy generating element 14 is an element that generates energy to eject liquid in the pressure chamber 12 from the injection orifice 11. Specifically, the first energy generating element 14 can eject ink from the injection orifice 11 by utilizing bubbling energy, which is generated by bubbling the liquid (also called ink) in the pressure chamber 12 by heating and driving. In this embodiment, an electrothermal conversion element is used as the first energy generating element 14; however, it is not particularly limited to this. For example, a piezoelectric element can be used as the first energy generating element 14.

[0057] In the substrate 18, the second energy generating element 24 is formed closer to the first supply opening 22 than the second supply opening 32. The second energy generating element 24 is an element that generates energy to produce a circulating flow of ink in a separate flow path 23 in the direction indicated by arrow 27. In this embodiment, an electrothermal conversion element is used as the second energy generating element 24; however, it is not particularly limited to this. For example, a piezoelectric element can be used as the second energy generating element 24.

[0058] Here, a straight-line shape is described. A straight-line shape means that the shape of the individual flow path 23 is formed such that the two end portions of the individual flow path 23 are located at the positions sandwiching the injection orifice 11, and the direction through the two end portions of the individual flow path 23 extends in a direction that intersects the direction along the row of injection orifices 11 (in the example of FIG. 3, a direction orthogonal to the direction along the row of injection orifices). In other words, in the individual flow path 23, the first energy generating element 14 and the second energy generating element 24 are arranged in a direction that intersects the direction along the row of injection orifices 11.

[0059] Furthermore, an inlet port-side connecting flow path 13 is formed on the side of the second energy generating element 24. The inlet port-side connecting flow path 13 is formed by a portion of a separate flow path 23 on the side of the second energy generating element 24 and the first supply opening 22. On the other hand, an outlet flow path is formed on the side of the first energy generating element 14. The outlet flow path is formed by another portion of a separate flow path 23 on the side of the first energy generating element 14 and the second supply opening 32.

[0060] Next, the flow of ink through the individual flow path 23 is described. The flow of ink through the individual flow path 23 is classified into two types of flow. The first flow of ink is the flow used for refilling after ink is ejected from the ejection orifice 11 when the liquid ejection device 50 drives the first energy generating element 14. The second flow of ink is the flow used to generate a circulating flow in the direction of arrow 27 when the liquid ejection device 50 drives the second energy generating element 24.

[0061] <The First Flow of Ink>

[0062] Figure 3D This illustrates a state in which the liquid jetting device 50 drives the first energy generating element 14 to eject ink from the jetting orifice 11. Figure 3D This is a diagram illustrating the inflow of ink when the first energy generating element 14 is driven. Figure 3D In the example shown, along with the ink ejection from the ejection orifice 11, ink is supplied from each of the first supply opening 22 and the second supply opening 32. Therefore, ink flows from both the first supply opening 22 and the second supply opening 32 into the pressure chamber 12.

[0063] <The Second Flow of Ink>

[0064] On the other hand, when the second energy generating element 24 is driven to generate a circulating flow, ink flows through the first supply opening 22 into a separate flow path 23, and ink flows out through the second supply opening 32 from the separate flow path 23. In this embodiment, when the liquid jetting device 50 returns ink flowing from the second supply opening 32 to the first supply opening 22 to circulate the ink, the liquid jetting device 50 generates a circulating flow of ink in the separate flow path 23 in the direction indicated by arrow 27. Figure 3C The example shown illustrates how the first supply opening 22 and the second supply opening 32 are shared in the liquid jet chip 3. Figure 3D This is an example where each of the first supply opening 22 and the second supply opening 32 is configured as a separate flow path, and each separate flow path is shared outside the liquid injection head 1.

[0065] The circulating flow of ink is further described. Ink comprises volatile components (such as water) and solid contents. When using the liquid ejection head 1, the ejection of ink from the ejection orifice 11 may be unstable due to the evaporation of volatile components in the ink from the ejection orifice 11, and the concentration of solid contents in the ink near the ejection orifice 11 as the volatile components in the ink evaporate. Therefore, various ideas have been considered to prevent unstable ejection of ink from the ejection orifice 11.

[0066] For example, a cover member (not illustrated) may be positioned at a location offset in the X direction from the transport path of the target medium P. The cover member is shaped to cover the surface of the injection orifice (in which the injection orifice 11 of the liquid injection head 1 is disposed). When the liquid injection head 1 is not performing a printing operation on the target medium P, the cover member prevents the injection orifice 11 from drying out and protects the injection orifice 11 by covering its surface.

[0067] In addition, an ink suction mechanism (not shown) may be provided. When a cover member and an ink suction mechanism are provided, the cover member cooperates with the ink suction operation from the ejection orifice 11. The ink suction operation updates the ink near the ejection orifice 11; therefore, the image quality of the acquired image can be maintained.

[0068] Furthermore, when the liquid ejector head 1 is not performing a printing operation on the target medium P, concentrated ink can be discarded by performing an ejection operation called pre-jet (also known as splatter). It is also known that when the liquid ejector head 1 is performing a printing operation on the target medium P, an ejection operation called pre-jet (also known as paper surface pre-jet or in-page pre-jet) is performed. Paper surface pre-jet or in-page pre-jet is an ejection operation used to eject a small amount of ink to an inconspicuous location so as not to affect the image quality on the target medium P. The ejection operation greatly contributes to improving the image quality; however, a portion of the ink is discarded to renew the ejection orifice 11. Therefore, it is preferable to minimize the amount of waste ink as much as possible.

[0069] To this end, ink circulation can be generated by placing a second energy generating element 24 for heating the ink in a separate flow path 23 in the substrate 18. Utilizing this ink circulation, the amount of waste ink can be suppressed, as can the drying of the ejection orifice 11 and the concentration of ink near the ejection orifice 11. From another perspective, the number of ink pre-ejections and ink intakes can be reduced as much as possible. Furthermore, by minimizing the number of ink pre-ejections, the overall throughput and production capacity of the liquid ejection device 50 can be improved. It should be noted that the effects described above can be achieved when the second energy generating element 24 is placed in at least a portion of one of the multiple separate flow paths 23, including the one in the liquid ejection head 1.

[0070] also, Figure 1A The liquid ejector head 1 may be configured such that the second energy generating element 24 is disposed in all portions corresponding to four types of ink, or may be configured such that the second energy generating element 24 is included in only a portion corresponding to one type of ink. That is, the liquid ejector head 1 may be configured such that only at least one type of ink out of multiple types is circulated.

[0071] Note that the ink circulation path can be set as follows: Figure 3A The illustrated filter 31 is used to remove foreign matter included in the ink. The filter 31 is formed by a protrusion that causes a portion of the perforated plate 19 to project toward the substrate 18. Figures 3A to 3DIn the example shown, filter 31 is positioned at one end and the other end of the individual flow path 23. In the ink circulation flow path, one end of the individual flow path 23 corresponds to the ink inflow side, and the other end of the individual flow path 23 corresponds to the ink outflow side. Filter 31 may be positioned in the individual flow path 23 between the first energy generating element 14 and the second energy generating element 24. If filter 31 is positioned in the individual flow path 23 between the first energy generating element 14 and the second energy generating element 24, filter 31 may not be positioned at one end and the other end of the individual flow path 23. Next, the principle of ink circulation generation will be described with reference to FIG4.

[0072] The principle behind ink circulation

[0073] Figure 4 is a diagram illustrating the principle of ink circulation. The filter 31 is omitted from Figure 4 for simplicity. Figure 4A yes Figure 3A The cross-sectional view of the individual injection unit is IIIB-IIIB and is a cross-sectional view describing the generation and growth process of bubble B generated by heating the ink using the second energy generating element 24 and causing the ink to boil in a film state. Figure 4B yes Figure 3A The cross-sectional view of the individual injection unit IIIB-IIIB' is a cross-sectional view describing the contraction process of bubble B generated by heating the ink using the second energy generating element 24 and causing the ink to boil in a film state. Figure 4C yes Figure 3A The diagram shows cross-sectional views of the individual injection units IIIB-IIIB', and also a cross-sectional view illustrating the process after the bubble B generated by heating the ink using the second energy generating element 24 and causing film boiling of the ink disappears. Next, the generation and growth process of bubble B, the contraction process, and the process after the bubble disappears will be described.

[0074] <The generation and growth process of bubble B>

[0075] like Figure 4A As illustrated, the second energy generating element 24 is positioned closer to the first supply opening 22 in the second supply opening 32. Therefore, in the case of circulating ink flow, the flow resistance R1 generated in the flow path between the second energy generating element 24 and the first supply opening 22 is less than the flow resistance R2 generated in the flow path between the second energy generating element 24 and the second supply opening 32. Therefore, as... Figure 4AAs illustrated, the difference between flow resistance R1 and flow resistance R2 causes bubbles B generated by the film boiling of the ink to grow, thus tending towards the side of the flow path with relatively lower flow resistance R1. Therefore, the flow vector Fa of the ink flowing towards the flow path that generates flow resistance R1 is greater than the flow vector Fb of the ink flowing towards the flow path that generates flow resistance R2. It should be noted that the circuit including flow resistances R1 and R2 is an equivalent circuit, in which the flow resistance generated by the circulating flow of ink in the flow path including the separate flow path 23 is expressed by comparing it with the resistance used as an example.

[0076] <The contraction process of bubble B>

[0077] During the contraction of bubble B, ink flows in to fill the internal volume created by the contraction of bubble B. In this process, as... Figure 4B As illustrated, the flow vector Fc of the ink flowing from the first supply opening 22 on the flow resistance R1 side is greater than the flow vector Fd of the ink flowing from the second supply opening 32 on the flow resistance R2 side. Furthermore, the bubble disappearance position of bubble B deviates from the position above the second energy generating element 24 towards the flow path closer to the second supply opening 32.

[0078] <The process after bubble B disappears>

[0079] For reference Figure 4BAs described, there exists a relationship Fc > Fd. Therefore, a flow vector F is generated for the circulating flow of ink from the first supply opening 22 to the second supply opening 32. The magnitude of the flow vector F is affected by the ratio between the flow resistances R1 and R2 and the size of the bubble B. For example, consider the case where a second energy generating element 24 is used. In this case, it is preferable that the arrangement position of the second energy generating element 24 is closer to one of the two end portions of the individual flow path 23 than the arrangement position of the first energy generating element 14. Specifically, it is preferable to set the flow resistance ratio R1 / R2 in the range of 0.05 to 0.40. When the flow resistance ratio R1 / R2 is set in the range of 0.05 to 0.40, the flow vector F of the circulating ink flow can be set to a local maximum. When the ink flow vector Fa increases and the ink flow vector Fc increases, the flow vector F of the circulating ink flow increases, and the circulating ink flow increases. Therefore, it is preferable to reduce the flow resistance R1. Furthermore, it is preferable to reduce the ink flow vector Fb and the ink flow vector Fd as much as possible. Therefore, it is preferable to increase the flow resistance R2. Based on the above, it is preferable to decrease the flow resistance R1 and increase the flow resistance R2. That is, it is preferable to decrease the flow resistance ratio R1 / R2. Furthermore, a larger bubble B size (i.e., a larger bubble B volume) means an increase in the volume of fluid expelled in the individual flow path 23, and thus an increase in circulating flow. For example, elements contributing to an increase in circulating flow include: increasing the size of the second energy generating element 24; increasing the width and height of the flow path on the side of the first supply opening 22 and a relative decrease in the flow path resistance R1; decreasing the viscosity of the ink; increasing the temperature of the liquid jet head 1; and changing the drive pulse to a dual pulse. Changing the drive pulse to a dual pulse means the following. First, the ink surrounding the flow path above the second energy generating element 24 is heated by applying a short pulse to the second energy generating element 24. This short pulse does not induce bubble formation in the flow path above the second energy generating element 24. Subsequently, with the application of a main pulse (which generates bubbles to circulate the ink) to the second energy generating element 24, larger bubbles grow. Specifically, with the first pulse, the ink temperature around the heater rises to a temperature close to boiling point over a wide range, and with the second pulse, the ink is immediately vaporized over the same wide range. Therefore, the number of bubbles increases. That is, the bubble volume is increased by applying two pulses.

[0080] Furthermore, a portion of the ink flowing through the ink circulation flow enters the interior of the ejection orifice 11. Therefore, the concentrated ink in the ejection orifice 11 is transferred to the flow path on the second supply opening 32 side, while fresh ink flows into the ejection orifice 11 from the flow path on the first supply opening 22 side via a separate flow path 23. This prevents the concentrated ink from stagnating in the ejection orifice 11. Thus, the initial ink ejection state can be maintained while suppressing the effects of concentrated ink.

[0081] When bubble B is generated, the ink circulation is a transitional flow accompanied by the growth and contraction processes. Therefore, after bubble B disappears, the inertial circulation of the ink decays over time and stops after a certain period. Therefore, to stably generate circulation within a certain time period, it is preferable to repeatedly drive the second energy generating element 24. It should be noted that the driving cycle of the second energy generating element 24 is not particularly limited as long as the concentrated ink retained in the jet orifice 11 can be discharged. It should be noted that when bubble B is generated, the ink circulation is a transitional flow accompanied by the growth and contraction processes. Therefore, if driving is performed at a high driving frequency (e.g., 100 kHz considering a period of 10 μs between the generation and disappearance of bubble B), it is possible that the circulation of the ink may be inhibited. Therefore, for example, it is preferable to drive the second energy generating element 24 with a driving cycle of approximately 100 Hz to tens of kHz.

[0082] Specifically, since the ink circulation is maintained at a higher driving frequency of the second energy generating element 24, the effect of discharging concentrated ink generated by the ink circulation is improved. However, it is assumed that the higher the driving frequency of the second energy generating element 24, the greater the increase in ink temperature caused by heating of the second energy generating element 24 due to its driving. Therefore, it is preferable to appropriately control the driving frequency of the second energy generating element 24. Next, the elimination of ink concentration accompanying the ink circulation will be described with reference to Figures 5 and 6.

[0083] <Elimination of ink concentration; straight line shape>

[0084] Figure 5 is a diagram illustrating the state of concentration elimination accompanying the circulating flow of ink in a single flow path 23 with a straight shape. Figure 5A This is a diagram illustrating a state where the circulating flow of ink has temporarily stopped. Figure 5B This is an example that follows through Figure 5A The diagram shows the state after the second energy generating element 24 is driven to generate the circulating flow of ink in the middle state. Figure 5C This is an example in Figure 5BThe diagram illustrates a state where the ink circulation temporarily stops after the initial state. Figure 5D This is an example that follows through Figure 5C The diagram illustrates the state after the second energy generating element 24 is driven to generate the circulating flow of ink, following the initial state. (See diagram for example.) Figures 5A to 5D As illustrated, the separate flow path 23 with a straight shape has a configuration in which the inlet and outlet ports for the circulating flow of ink are separate. Note that dotted shading is applied to the ink in the separate flow path 23, and shading with high-concentration dots is applied to the portions containing concentrated ink to express the degree of ink concentration.

[0085] like Figure 5A As illustrated, when the ink circulation temporarily stops, the volatile components of the ink evaporate from the nozzle 11. Therefore, ink concentration proceeds near the nozzle 11. Subsequently, when the second energy generating element 24 is activated, the ink circulation resumes. Thus, as... Figure 5B As illustrated, the ink concentration that had progressed near the jet orifice 11 was eliminated. Subsequently, once the ink circulation temporarily ceased, such as... Figure 5C exemplified, as Figure 5A Ink concentration resumes near the jet orifice 11. Then, with the second energy generating element 24 activated, the ink circulation restarts. Therefore, as... Figure 5D exemplified, as Figure 5B The ink concentration that has progressed near the injection orifice 11 is eliminated. Therefore, ink concentration throughout the entire individual flow path 23 is also eliminated. As described above, in the individual flow path 23, which has a straight shape, the ink concentration state is reset each time the ink circulation flow is repeatedly paused and restarted.

[0086] <Elimination of ink concentration; U-shape>

[0087] Figure 6 is a diagram illustrating the state of concentration elimination accompanying the circulating flow of ink in a separate flow path 23 with a U-shape. Figure 6A This is a diagram illustrating a state where the circulating flow of ink has temporarily stopped. Figure 6B This is an example that follows through Figure 6A The diagram shows the state after the second energy generating element 24 is driven to generate the circulating flow of ink in the middle state. Figure 6C This is an example in Figure 6B The diagram illustrates a state where the ink circulation temporarily stops after the initial state. Figure 6D This is an example that follows through Figure 6C The diagram illustrates the state after the second energy generating element 24 is driven to generate the circulating flow of ink, following the initial state. (See diagram for example.) Figures 6A to 6DAs illustrated, the U-shaped individual flow path 23 has a configuration in which the inlet and outlet ports of the circulating ink flow are adjacent to each other. Note that dotted shading is applied to the ink in the individual flow path 23, and shading with high-concentration dots is applied to the portions containing concentrated ink to indicate the degree of ink concentration.

[0088] like Figure 6A As illustrated, when the ink circulation temporarily stops, the volatile components of the ink evaporate from the nozzle 11. Therefore, ink concentration proceeds near the nozzle 11. Subsequently, once the second energy generating element 24 is activated, the ink circulation resumes. Thus, [the desired effect is achieved]. Figure 6B The illustrated state. Figure 6A The inlet port of the separate flow path 23 in the middle and Figure 6A The outlet port of the separate flow path 23 is adjacent to the nozzle 11. Therefore, the ink concentrated near the nozzle 11 is discharged from the outlet port of the separate flow path 23, but a portion of the discharged ink flows back into the inlet port of the separate flow path 23. Thus, a phenomenon occurs where the entire separate flow path 23 is not replaced with fresh ink but with slightly concentrated ink (hereinafter referred to as recirculation concentration). Afterwards, once the ink circulation temporarily stops, such as... Figure 6C exemplified, and Figure 6A Similarly, from Figure 6B The ink concentration process begins again near the nozzle 11. Afterwards, once the second energy generating element 24 is activated, the ink circulation resumes. Therefore, as... Figure 6D As illustrated, due to the effect of recycling and concentration, the entire individual flow path 23 is replaced by a higher concentration. Figure 6B The ink in the flow path 23 is more concentrated. As mentioned above, in the U-shaped single flow path 23, the ink concentration is not reset each time the ink circulation is temporarily stopped and the circulation operation is repeated, and the ink concentration gradually progresses throughout the single flow path 23. Therefore, the ink concentration deteriorates. It should be noted that even if the temporary stop and restart of the ink circulation is not repeated, if the ink concentration near the nozzle 11 progresses due to the temporary stop of the ink circulation for a long period of time, it is difficult to achieve an improvement in the ink concentration even if the ink circulation is restarted immediately. This is because the improvement in the ink concentration achieved through recirculation concentration is relatively small.

[0089] Therefore, due to the difference in the effect of the discharged concentrated ink, the single flow path 23 with a straight shape and the single flow path 23 with a U-shape have different effects on eliminating the concentrated state of the ink through the temporary stop and restart of the ink circulation flow. Specifically, in the case of the single flow path 23 with a straight shape, the concentrated state of the ink throughout the single flow path 23 may be eliminated. On the other hand, in the case of the single flow path 23 with a U-shape, the concentrated state of the ink throughout the single flow path 23 cannot be eliminated due to recirculation concentration. Therefore, in the case of the single flow path 23 with a U-shape, there is a possibility of unstable ink ejection depending on the degree of concentration throughout the single flow path 23. Next, the configuration near the ejection orifice 11 in the single flow path 23 with a U-shape will be described with reference to FIG7.

[0090] <Configuration near the injection orifice 11 in a separate flow path 23 with a U-shape>

[0091] Figure 7 is a diagram showing the vicinity of the injection orifice 11 in a separate flow path with a U-shape, which is described in detail. Figure 7A This is a plan view taken from the direction of the liquid droplets ejected from the nozzle 11. Figure 7B yes Figure 7A Cross-sectional view of VIIB-VIIB. Figure 7C yes Figure 7A An enlarged schematic diagram of the individual flow path 23 in the diagram.

[0092] Figure 7A and Figure 7B The injection orifice 11 is an opening formed in a portion of the perforated plate 19. In the substrate 18, a first energy generating element 14 is formed at a position corresponding to the portion directly below the injection orifice 11. A second energy generating element 24 is also formed in the substrate 18. The second energy generating element 24 generates a circulating flow of ink in a flow path including a separate flow path 23 in the direction indicated by arrow 27. In the substrate 18, a supply groove 42 is formed to penetrate the substrate 18 in the direction along the row of the injection orifice 11 between the rows of the first energy generating elements 14 and the rows of the second energy generating elements 24. The supply groove 42 communicates with the separate flow path 23 and can supply ink to the separate flow path 23. Therefore, not only can a configuration of multiple independent supply openings being provided as the first supply opening 22 and the second supply opening 32 in FIG. 3 be applied, but a configuration that allows liquid inflow and outflow by using a large opening as the common supply groove 42 in FIG. 7 can also be applied. Next, the configuration near the injection orifice 11 in the separate flow path 23 having a straight shape will be described with reference to FIG. 8.

[0093] <Configuration near the injection orifice 11 in a separate flow path 23 with a straight shape>

[0094] Figure 8 is a diagram showing the vicinity of the injection orifice 11 in a single flow path 23 with a straight shape, which is described in detail. Figure 8A This is a plan view taken from the direction of the liquid droplets ejected from the nozzle 11. Figure 8B yes Figure 8A Cross-sectional view of VIIB-VIIB. Figure 8C yes Figure 8A The cross-sectional view of VIIB-VIIB and the internal configuration of substrate 18. Figure 8B Different cross-sectional views of the internal configuration of the substrate. Figure 8B and Figure 8C Two examples of different shapes of the rear side of substrate 18 are illustrated, depending on the type of etching method performed on substrate 18; however, the shape of the rear side of substrate 18 can be any shape. That is, the internal configuration of substrate 18 can be any configuration.

[0095] The difference between this configuration and the configuration near the injection orifice 11 in a U-shaped individual flow path 23 is that, unlike the U-shaped individual flow path 23, it is a straight-line configuration in which the inlet and outlet ports of the individual flow path 23 are not adjacent to each other, and the inlet and outlet ports of the individual flow path 23 are separate from each other. Furthermore, as... Figure 8A As illustrated, the directions connecting the two ends of the individual flow paths 23, which have a straight shape, are orthogonal to the direction of the jet orifices 11 arranged to form a row. In the arrangement described above, the position where the circulating ink flows into the individual flow path 23 is far from the position where the circulating ink flows out. Therefore, it is possible to prevent ink concentrated in the jet orifices 11 from flowing back into the individual flow path 23. Thus, the effect of ink concentration can be suppressed. Next, another arrangement near the jet orifices 11 in the individual flow paths 23 with a straight shape will be described with reference to FIG9.

[0096] <Another configuration near the injection orifice 11 in a separate flow path 23 with a straight shape>

[0097] Figure 9 is another schematic diagram depicting the vicinity of the injection orifice in a single flow path 23 with a straight shape. Figure 9A This is a plan view taken from the direction of the liquid droplets ejected from the nozzle 11. Figure 9B yes Figure 9A Cross-sectional view of IXB-IXB. Figure 9C yes Figure 9A The cross-sectional view of IXB-IXB and the internal configuration of substrate 18. Figure 9BDifferent cross-sectional views of the internal configuration of the substrate. Figure 9B and Figure 9C Examples of different shapes for the rear side of substrate 18, depending on the type of etching method performed on substrate 18, are shown; however, the shape of the rear side of substrate 18 can be any shape. That is, the internal configuration of substrate 18 can be any configuration. Furthermore, unlike FIG8, the number of rows of ink supply openings is increased by one row, from two rows to three rows. Therefore, the number of rows of jet orifices 11 can be doubled, and the rows of jet orifices 11 can be arranged on one side close to the central ink supply opening. That is, the rows of jet orifices 11 are arranged on both sides along the arrangement direction of the plurality of ink supply openings on the central side. Using the arrangement described above, the number of ink supply openings can be increased by one row, from two rows to three rows, and the number of jet orifices 11 can be doubled from one row to two rows. Furthermore, as... Figure 9A As illustrated, two rows of injection orifices 11 can be arranged at an alternating spacing between the two rows of injection orifices 11. Furthermore, the wiring area may not be included between the supply openings in the central row of ink supply openings. Therefore, the size and resolution of the openings in the central row of ink supply openings have a high degree of freedom. Thus, the refilling speed of the injection orifices 11 can be increased and high productivity can be achieved. It should be noted that the positions of the injection orifices 11 and the ink supply openings can be shifted according to the wiring route. Next, the ink according to this embodiment will be described.

[0098] <Ink>

[0099] As described above, although the degree of ink concentration reduction varies depending on the flow path configuration including the individual flow path 23, the following effect can be achieved by using the second energy generating element 24 to generate a circulating flow of ink in the individual flow path 23. That is, the effect of concentrated ink thickening due to the evaporation of volatile components of the ink through the injection orifice 11 can be suppressed. Therefore, since a good ink ejection state can be maintained, the effect of changing the ink ejection speed can be further reduced. Therefore, stable ink ejection can be achieved.

[0100] On the other hand, depending on the application of the liquid ejector head 1 and the liquid ejection device 50 on which the liquid ejector head 1 is mounted, it can be assumed that inks with different types of color materials or inks with different contents of solids can be used. That is to say, in terms of the performance of the liquid ejector head 1, it is preferable that the ink ejection stability can be maintained when using any type of ink.

[0101] For example, as a result of water in the ink, changes such as curling (also known as warping) and wrinkling (also known as wavy wrinkling) may occur on ordinary paper. In this case, it is advisable to use ink with a reduced amount of water. Furthermore, ink with a small amount of water has a high concentration of solid contents, such as organic solvents, pigments, and resins other than water. Therefore, as the water in the ink evaporates, the viscosity of the ink may increase rapidly. Therefore, ink with a small amount of water may cause a decrease in the ink's jetting stability. Therefore, when using ink with a small amount of water, the increase in ink viscosity can be suppressed by generating circulating flow of ink in a flow path configuration including the separate flow path 23 according to this embodiment. Generally speaking, ink with a large amount of solid contents has 10% by weight of solid contents. That is, it is preferable to apply this embodiment to ink with a solid content of 10% by weight (also known as mass%) or more.

[0102] The relationship between the operating temperature of the liquid ejector head 1 and the viscosity of the ink is described. There exists a scenario where the second energy-generating element 24, arranged throughout the liquid ejector chip 3, is driven and controlled, and the temperature of the liquid ejector head is heated until the temperature of the liquid ejector head 1 reaches a certain operating temperature. The viscosity of the ink changes according to the ink temperature. Therefore, the viscosity of the ink at the operating temperature of the liquid ejector head 1 affects the stability of ink ejection.

[0103] The relationship between the ink circulation rate and the driving frequency of each of the first energy generating element 14 and the second energy generating element 24 is described. When the ink circulation is generated by the second energy generating element 24, an instantaneous ink circulation rate in the range of tens of mm / s to 1000 mm / s can be achieved. The average flow rate within a time window on the order of hundreds of μs depends on the driving frequency of the second energy generating element 24. This is because, when the ink circulation is generated by the second energy generating element 24, the ink circulation is a transitional circulation that decays over time and stops after a certain period. On the other hand, when the ink circulation is generated by the first energy generating element 14, it can be driven at a frequency of approximately 10 kHz to 20 kHz, which is comparable to the driving frequency (also called the jetting frequency) of the first energy generating element 14. In this case, the average flow rate of the ink circulation can be from a few mm / s to 100 mm / s. Next, the relationship between pigment concentration and the elimination of ink concentration is described.

[0104] (Ink with a high concentration of pigment)

[0105] The case of inks with high pigment concentrations is described. For example, when using inks with a certain concentration (where the ink viscosity is above 3 cP and below 6 cP at the operating temperature of the liquid jet head 1), thickening of the ink near the jet orifice 11 may occur depending on the non-jetting time of the ink (also known as the stopping time of the ink's circulating flow). Therefore, the ink jetting speed may change. Consequently, the stability of ink jetting may decrease. To suppress the decrease in ink jetting stability, it is preferable to circulate the ink by generating a circulating flow while the stopping time of the ink's circulating flow is still short. Therefore, it is preferable to eliminate ink concentration by performing static or transient circulation of the ink at a high frequency. For this purpose, transient circulation of the ink can be performed by driving the second energy generating element 24. Therefore, by driving the second energy generating element 24 and restarting the ink's circulating flow from the stopping state of the ink's circulating flow at a high frequency, it is helpful to eliminate ink concentration near the jet orifice 11.

[0106] (Ink with low pigment concentration)

[0107] This article describes an ink with a low pigment concentration. For example, when using ink with a certain concentration (where the ink viscosity is above 1 cP and below 2 cP at the operating temperature of the liquid ejector head 1), there is a possibility that the ink thickening near the ejector orifice 11 progresses according to the non-ejection time of the ink (also known as the stop time of the ink circulation flow). Therefore, although there is a possibility of a change in the ink ejection speed, the change in the ejection speed of this ink is relatively small compared to the ejection speed of ink with a high concentration. On the other hand, if, for example, the stop time of the ink circulation flow is long, there is a possibility that the ink thickening near the ejector orifice 11 progresses according to the non-printing drive time (also known as the stop time). Therefore, when resuming operation after a period of inactivity, it is preferable to perform a recycling process associated with waste ink, including an ink intake operation, a wiping operation, and a pre-ejection as a combination of the above. For this purpose, when the second energy generating element 24 is driven, the restart of the ink circulation flow serves as a recycling operation and can help eliminate the concentration of ink near the ejector orifice 11 without generating waste ink. Furthermore, depending on the stop time, waste ink generation can be prevented through a recycling process that simply restarts the ink circulation by activating the second energy generating element 24. Alternatively, waste ink recycling can be performed by combining recycling that restarts the ink circulation with a suction operation to remove air bubbles B from the liquid jet head 1 (this suction operation is different from the elimination of ink concentration).

[0108] (A more preferred configuration for eliminating ink concentration)

[0109] As described above, in either case, whether the ink has a high concentration or a low concentration, it is preferable to restore the ink to its initial fresh state as much as possible to suppress the effect of concentrated ink. Therefore, when driving the second energy generating element 24, the smaller the effect of recirculation concentration, the higher the circulation effect can be achieved. That is, compared to a U-shape, a higher circulation effect can be achieved by utilizing a configuration with a single flow path 23 having a straight shape. Next, refer to... Figures 10 to 20 The circuit configuration for driving and controlling the first energy generating element 14 and the second energy generating element 24 according to this embodiment is described.

[0110] <Heater Selection Circuit>

[0111] Figure 10This is a diagram illustrating an example of the circuit configuration of the print element substrate 300 according to this embodiment. Various signals are supplied from the main substrate 400 to the print element substrate 300. The main substrate 400 includes a power supply circuit 401 and a controller 402. The power supply circuit 401 applies a power supply voltage to the print element substrate 300 via a power supply line VH. The power supply circuit 401 and the print element substrate 300 are connected to each other via a ground line GNDH. The ground line GNDH is included in a grounding layer. The grounding layer sets a reference potential for the print element substrate 300. Therefore, the ground line GNDH serves as a reference potential for the print element substrate 300. The controller 402 is mainly formed of a ROM, RAM, and CPU, and supplies various electrical signals to the print element substrate 300. The controller 402 is connected to the print element substrate 300 via an enable signal line HE, a latch signal line LT, a data signal line DATA, and a clock signal line CLK. The controller 402 supplies an enable signal via the enable signal line HE. An enable signal is a signal used to control the timing of the control target element being turned on and current flowing during the pulse width. The enable signal is used to adjust for more ideal thermal energy generation, taking into account factors such as manufacturing irregularities in the heater resistance values ​​in the printed element substrate 300, manufacturing irregularities in the power supply circuit 401, and voltage drop in the power supply wiring when multiple heaters are driven simultaneously. In this embodiment, an example is described where the enable signal line HE is shared between jetting and cycling to reduce the number of signal terminals; however, different pulse widths for jetting and cycling can also be set by providing separate enable signal lines HE for jetting and cycling. It should be noted that when the enable signal line HE is shared between jetting and cycling (as in this embodiment), the following configuration is preferred. That is, assuming that the jetting heater RhA and the cycling heater RhB are formed in the same process of semiconductor manufacturing and have the same manufacturing irregularities (the amount of deviation of the resistance value from the ideal value), it is preferable to adjust the pulse width of the enable signal. The controller 402 supplies a latch signal to the printed element substrate 300 via the latch signal line LT. The controller 402 supplies data signals to the printing element substrate 300 via the data signal line DATA. The controller 402 supplies clock signals to the printing element substrate 300 via the clock signal line CLK.

[0112] The printing element substrate 300 includes jetting modules 301 and 302 and circulation modules 303 and 304. Jetting modules 301 and 302 respectively include a jetting heater RhA, jetting drive elements MD1 and MD2, and jetting logic circuits AND1 and AND2. The jetting heater RhA is a jetting energy generating element. The first energy generating element 14 is also a jetting energy generating element. That is, although the jetting heater RhA and the first energy generating element 14 are referred to the same way, these terms are used differently depending on whether it is a circuit element or an element arranged in a structure with a separate flow path 23. The jetting drive elements MD1 and MD2 are elements that allow current to flow to the jetting heater RhA, respectively. The jetting logic circuits AND1 and AND2 are elements that selectively drive the jetting drive elements MD1 and MD2, respectively. The printing element substrate 300 generates heat by allowing current to flow to the jetting heater RhA. Therefore, printing can be performed on the jetting target medium P when ink bubbles and is jetted.

[0113] Circulation modules 303 and 304 respectively include a circulation heater RhB, circulation drive elements MD3 and MD4, and circulation logic circuits AND3 and AND4. The circulation heater RhB is a circulation energy generating element. The second energy generating element 24 is also a circulation energy generating element. That is, although the circulation heater RhB and the second energy generating element 24 are referred to the same way, these terms are used differently depending on whether it is a circuit element or an element arranged in a structure with a separate flow path 23. Circulation drive elements MD3 and MD4 are elements that allow current to flow to the circulation heater RhB, respectively. Circulation logic circuits AND3 and AND4 are elements that selectively drive circulation drive elements MD3 and MD4, respectively. The printing element substrate 300 generates heat by allowing current to flow to the circulation heater RhB. Therefore, ink bubbles B grow, and a circulating flow can be generated in the ink's flow path, which includes a separate flow path 23.

[0114] It should be noted that in the jet heater RhA, the piezoelectric element can be used as the element for jetting ink. In the circulation heater RhB, the piezoelectric element can be used as the element for circulating ink. Each of the jet driving elements MD1 and MD2 and the circulation driving elements MD3 and MD4 is an N-type high-voltage transistor, which is therefore a transistor with a higher voltage tolerance compared to transistors used in logic circuits. Preferably, the high-voltage transistor is configured not to be damaged by large voltages (e.g., 32V) that cannot be withstood by general logic circuit transistors forming the control unit.

[0115] The printing element substrate 300 includes a control data supply circuit 305. The printing element substrate 300 is provided with a group selection signal line 306, a time-division selection signal line 307, and an enable signal line HE. The control data supply circuit 305 is electrically connected to each of the group selection signal line 306, the time-division selection signal line 307, and the enable signal line HE. Each of the group selection signal line 306, the time-division selection signal line 307, and the enable signal line HE is electrically connected to the jetting modules 301 and 302 and the circulation modules 303 and 304. Therefore, the control data supply circuit 305 can transmit various signals to and receive various signals from the jetting modules 301 and 302 and the circulation modules 303 and 304 via the group selection signal line 306 and the time-division selection signal line 307.

[0116] Specifically, each of the group selection signal line 306, the time-division selection signal line 307, and the enable signal line HE is connected to the input side of the injection logic circuits AND1 and AND2. The output side of the injection logic circuit AND1 is connected to the injection drive element MD1. The output side of the injection logic circuit AND2 is connected to the injection drive element MD2. Therefore, according to the output of the injection logic circuit AND1, the injection drive element MD1 becomes on and performs selective control, causing current to flow to the injection heater RhA. Similarly, according to the output of the injection logic circuit AND1, the injection drive element MD2 becomes on and performs selective control, causing current to flow to the injection heater RhA. Furthermore, according to the output of the loop logic circuit AND3, the loop drive element MD3 becomes on and performs selective control, causing current to flow to the loop heater RhB. Similarly, according to the output of the loop logic circuit AND4, the loop drive element MD4 becomes on and performs selective control, causing current to flow to the loop heater RhB.

[0117] It should be noted that, although not illustrated, the control data supply circuit 305 includes a shift register and a latch circuit. In the shift register, serial data transmission of the time-division selection signal is performed according to the clock signal. The latch circuit holds the time-division selection signal according to the latch signal.

[0118] (First scenario)

[0119] Figure 11 This is a diagram illustrating an example arrangement of the heater and drive element according to a first case of this embodiment. Figure 11 In this configuration, a jet heater RhA and a circulating heater RhB are arranged as heaters in the printed element substrate 300. Furthermore, in... Figure 11 In this process, jetting drive elements MD1 and MD2, and circulation drive elements MD3 and MD4 are arranged in the printing element substrate 300 as driving elements. Furthermore, in Figure 11 In this embodiment, drain connections 216, 217, 218, and 219 are arranged in the printed element substrate 300. It should be noted that in the following description, it is assumed that each of the jet driving elements MD1 and MD2 is formed by a metal-oxide-semiconductor field-effect transistor (MOSFET). Furthermore, in the following description, it is assumed that each of the cycle driving elements MD3 and MD4 is formed by a MOSFET. It should be pointed out that each of the jet driving elements MD1 and MD2 and the cycle driving elements MD3 and MD4 can be formed by elements other than MOSFETs. For example, each of the jet driving elements MD1 and MD2 and the cycle driving elements MD3 and MD4 can be formed by a bipolar transistor. Alternatively, each of the jet driving elements MD1 and MD2 and the cycle driving elements MD3 and MD4 can be formed by an insulated-gate bipolar transistor (IGBT).

[0120] Specifically, in Figure 11 In the example shown, supply port rows 205 and 206, jet heater row 201, circulation heater row 202, jet drive element row 203, and circulation drive element row 204 are arranged in the print element substrate 300. In this embodiment, jet heater row 201 is arranged parallel to the left side of supply port row 205. Circulation heater row 202 is arranged parallel to the left side of jet heater row 201. Supply port row 206 is arranged parallel to the left side of circulation heater row 202. Circulation drive element row 204 is arranged parallel to the left side of supply port row 206. Jet drive element row 203 is arranged parallel to the left side of circulation drive element row 204. A via VIA is provided between circulation heater row 202 and supply port row 206. The via VIA located between circulation heater row 202 and supply port row 206 is electrically connected to a power line VH on another wiring layer. A via VIA is provided between circulation drive element row 204 and jet drive element row 203. The via VIA located between the cycle drive element row 204 and the injection drive element row 203 is electrically connected to the ground wire GNDH on another wiring layer. The via VIA is located on the left side of the injection drive element row 203. The via VIA located on the left side of the injection drive element row 203 is electrically connected to the ground wire GNDH on another wiring layer.

[0121] In this embodiment, it is assumed that the current of the circulating heater RhB is less than the current of the jet heater RhA. Figure 11In the example, the element area in the row width direction of the cycle drive elements MD3 and MD4 is smaller than the element area in the row width direction of the injection drive elements MD1 and MD2. Here, it is assumed that the row width direction is a lateral direction, which is within the same row as the lateral direction orthogonal to the row length (also called the longitudinal direction) of the row formed by multiple elements that are arranged as targets in a row.

[0122] In row 201 of the injection heaters, multiple injection heaters RhA are arranged in a row. For example, the arrangement density of injection heaters RhA is 600 dpi. In row 202 of the circulating heaters, multiple circulating heaters RhB are arranged in a row. Circulating heaters RhB are arranged in pairs adjacent to injection heaters RhA. In row 203 of the injection drive elements, multiple units are arranged in which injection drive elements MD1 and MD2 are arranged adjacent to each other along the row direction. In each unit, a shared ground electrode 209 is arranged as a shared electrode between injection drive element MD1 and the injection drive element MD2 adjacent to injection drive element MD1. The shared ground electrode 209 is electrically connected to the ground wire GNDH on another wiring layer through a via VIA. In row 204 of the circulating drive elements, multiple units are arranged in which circulating drive elements MD3 and MD4 are arranged adjacent to each other along the row direction. In each unit, a shared ground electrode 210, serving as a shared electrode, is arranged between the cyclic drive element MD3 and the adjacent cyclic drive element MD4. Like the shared ground electrode 209, the shared ground electrode 210 is electrically connected to a ground wire GNDH on another wiring layer via a via VIA.

[0123] The distance P2 between the centers of gravity of the jet drive elements MD1 and MD2 for the corresponding units is smaller than the distance P1 between the centers of gravity of the jet heaters RhA. The distance P2 between the centers of gravity of the jet drive elements MD1 and MD2 for the corresponding units is smaller than the distance P1 between the centers of gravity of the circulating heaters RhB. For example, when the jet heaters RhA are arranged at 600 dpi, the distance P1 is 42.3 μm. On the other hand, for each unit, when including the shared ground electrode 209, the distance P2 is approximately 32 μm. Therefore, there is approximately 10 μm of extra space. By utilizing this extra space, the substrate contacts 220 can be arranged between the units of the jet drive elements MD1 and MD2. Furthermore, by utilizing this extra space, drain wirings 216 and 217 can also be wired between the units of the circulating drive elements MD3 and MD4. Here, the center of gravity refers to the center of the element region of the extraction unit, which also includes the electrode required for driving. Specifically, the center of gravity is the point where the center of an element between one end and the other end in the row length direction intersects with the center of an element between one end and the other end in the row width direction.

[0124] The jet heater RhA and the circulating heater RhB are connected to power supply wiring 207. Figure 11 In the example, two jet heaters RhA and two circulating heaters RhB are connected to a single power supply terminal 207. That is, four heaters are connected to a common power supply terminal 207. Power supply terminal 207 is connected to a power supply line VH on another terminal layer via via VIA. Note that eight or sixteen heaters can be connected to the common power supply terminal 207, provided the current density and power supply resistance are permissible.

[0125] It should be noted that although the circulating heater RhB is used for circulation in this embodiment, a heater with a smaller drive current than the jet heater RhA can also be used. Furthermore, in this case, the area of ​​the drive element for driving the heater (which is not labeled as a circulation element since it is not used for circulation) in the row width direction is smaller than the area of ​​the jet drive elements MD1 and MD2 in the row width direction. Moreover, although... Figure 11 Supply port line 206 is configured, but it may not be applied. Furthermore, although in Figure 11 The independent supply port 208 is arranged as supply port row 205, but a non-independent, elongated supply port can also be arranged. Furthermore, in Figure 11The example shown illustrates an instance where the center of gravity of the cycle drive element MD3 is located on an imaginary extension line (which extends from the center of gravity of the injection drive element MD1 along a line width direction orthogonal to the line length direction of the injection drive element row 203), and is on the same layer as the centers of gravity of injection drive elements MD1 and MD2. Similarly, in Figure 11 An example is illustrated where the center of gravity of the cyclic drive element MD4 is located on an imaginary extension line (which extends from the center of gravity of the injection drive element MD4 along a line width direction orthogonal to the line length direction of the injection drive element row 203), and is on the same layer as the centers of gravity of the injection drive elements MD1 and MD2. That is, in a coordinate system where the imaginary extension line along the line length direction is the longitudinal axis and the imaginary extension line along the line width direction is the transverse axis, the centers of gravity of the injection drive element MD1 and the cyclic drive element MD3 are located on the same coordinate in the line width direction. Similarly, in a coordinate system where the imaginary extension line along the line length direction is the longitudinal axis and the imaginary extension line along the line width direction is the transverse axis, the centers of gravity of the injection drive element MD2 and the cyclic drive element MD4 are located on the same coordinate in the line width direction. It should be noted that in... Figure 11 The text describes an example where the center of gravity of injection drive element MD1 and the center of gravity of circulation drive element MD3 lie on the same coordinate in the row width direction, and the center of gravity of injection drive element MD2 and the center of gravity of circulation drive element MD4 lie on the same coordinate in the row width direction. That is, although an example is described where the center of gravity of injection drive element MD1 and the center of gravity of circulation drive element MD3 lie on the same imaginary extension line, and the center of gravity of injection drive element MD2 and the center of gravity of circulation drive element MD4 lie on the same imaginary line, it is not limited to this example. The distance between the centers of gravity of injection drive element MD1 and injection drive element MD2 can be greater than the distance between the centers of gravity of circulation drive element MD3 and circulation drive element MD4. Even in the arrangement configuration described above, drain wires 216 and 217 can be wired between the cells of circulation drive element MD3 and circulation drive element MD4.

[0126] (Second scenario)

[0127] Figure 12 This is a diagram illustrating an example arrangement of the heater and drive element according to a second case of this embodiment. Figure 12 In this configuration, a jet heater RhA and a circulating heater RhB are arranged as heaters in the printed element substrate 300. Furthermore, in... Figure 12In this process, jetting drive elements MD1 and MD2, and circulation drive elements MD5 and MD6 are arranged as driving elements in the printing element substrate 300. Furthermore, in Figure 12 In this case, drain terminals 316, 317, 318, and 319 are arranged in the printed element substrate 300. The difference from the first case is that the positional relationship between the jet heater row 201 and the circulation heater row 202 is reversed. That is, the jet heater row 201 is arranged on the drive element region side relative to the circulation heater row 202, which includes jet drive elements MD1 and MD2 and circulation drive elements MD5 and MD6. Therefore, the arrangement of the drive elements also differs from the first case.

[0128] Specifically, the cells of the cycle drive elements MD5 and MD6 are arranged to be shifted by half a pitch from the cells of the injection drive elements MD1 and MD2 in the row length direction. That is, in Figure 12 The example illustrates an instance where the center of gravity of the cycle drive element MD5 is not located on the imaginary extension line (which extends from the center of gravity of the injection drive element MD1 along a row width direction orthogonal to the row length direction of the injection drive element row 203), and is not on the same layer as the centers of gravity of the injection drive elements MD1 and MD2. Similarly, in Figure 12An example is illustrated where the center of gravity of the cyclic drive element MD6 is not located on an imaginary extension line (which extends from the center of gravity of the injection drive element MD2 along a line width direction orthogonal to the line length direction of the injection drive element row 203), and is not on the same layer as the centers of gravity of the injection drive elements MD1 and MD2. In other words, in a coordinate system where the imaginary extension line along the line length direction is the longitudinal axis and the imaginary extension line along the line width direction is the transverse axis, the center of gravity of the injection drive element MD1 and the cyclic drive element MD5 are not located on the same coordinate system in the line width direction. Similarly, in a coordinate system where the imaginary extension line along the line length direction is the longitudinal axis and the imaginary extension line along the line width direction is the transverse axis, the center of gravity of the injection drive element MD2 and the cyclic drive element MD6 are not located on the same coordinate system in the line width direction. In this case, it is assumed that the position within the cell is a reference position, and a spacing is defined as the distance interval to the same reference position of adjacent cells. The half-pitch is half a pitch. Therefore, even in an arrangement where the drain wires 318 and 319 of the circulation drive elements MD5 and MD6 are electrically connected to the circulation heater RhB, the following configuration can be applied using the displacement of the half-pitch. That is, the drain wires 316 and 317 of the injection drive elements MD1 and MD2 can be connected to the injection heater RhA on the same wiring layer by wiring the drain wires 316 and 317 between the units of the circulation drive elements MD5 and MD6.

[0129] It should be noted that, as is already known, it is more preferable to uniformly arrange the substrate contacts 220 in a region that is wider than the arrangement of the jet drive element row 203 and the circulation drive element row 204, in order to suppress faults such as latch-up. Therefore, if the positional relationship between the jet heater row 201 and the circulation heater row 202 is the opposite of the first case, a configuration in which the positional relationship between the jet drive element row 203 and the circulation drive element row 204 is also reversed can be considered. However, in the second case, since wider substrate contacts 220 can be arranged along the row width direction between the units of the jet drive element MD1 and the jet drive element MD2, the jet drive element row 203 is arranged on the left side of the circulation drive element row 304.

[0130] (Third scenario)

[0131] Figure 13 This is a diagram illustrating an example arrangement of the heater and drive element according to a third case of this embodiment. Figure 13 In this configuration, a jet heater RhA and a circulating heater RhB are arranged as heaters in the printed element substrate 300. Furthermore, in... Figure 13In this process, jetting drive elements MD51, MD52, MD53, and MD54, and circulating drive elements MD55, MD56, MD57, and MD58 are arranged as driving elements in the printing element substrate 300. Furthermore, in Figure 13 In this case, drain wires 266, 267, 268, 269, 270, 271, 272, and 273 are arranged in the printing element substrate 300. The difference from the first and second cases is that, in the third case, a unit is formed by four adjacent drive elements, compared to the first and second cases where a unit is formed by two adjacent drive elements. Although the number of drive elements in the unit differs from the first and second cases, the similarity is that the distance P4 between the centroids of the jet drive elements MD51 and MD52 in the unit is smaller than the distance P1 between the centroids of the jet heater RhA and the circulating heater RhB. Therefore, by utilizing the extra space created by the shared ground electrodes 259 and 260 in the unit, the substrate contacts 220 can be arranged between units in the jet drive element row 253. Furthermore, by utilizing the extra space, drain wires 266, 267, 272, and 273 can be wired between units in the circulating drive element row 254.

[0132] It should be noted that the spacing between supply ports 208 in the first case and supply ports 258 in the third case differs. In cases with a wider spacing (such as supply port 258), there is a configuration in which a cell is formed by four drive elements or by four or more drive elements to improve the efficiency of wiring such as drain wiring 266. With this configuration, electrodes can be shared in the boundary portions between cells, and thus the expansion of the drive element region can be suppressed.

[0133] (Fourth scenario)

[0134] Figure 14 This is a diagram illustrating an example arrangement of the heater and drive element according to the fourth case of this embodiment. Figure 14 In this configuration, a jet heater RhA and a circulating heater RhB are arranged as heaters in the printed element substrate 300. Furthermore, in... Figure 14 In this process, jetting drive elements MD51, MD52, MD53, and MD54, and circulating drive elements MD59, MD60, MD61, and MD62 are arranged in the printing element substrate 300 as driving elements. Furthermore, in Figure 13In this configuration, drain terminals 366, 367, 368, 369, 370, 371, 372, and 373 are arranged in the printed element substrate 300. The difference from the third case is that the positional relationship between the jet heater row 201 and the circulating heater row 202 in the row width direction is reversed. Therefore, as in the second case, there exists a configuration in which the cells in the circulating drive element row 354 are shifted by half a pitch from the cells in the jet drive element row 253 in the row length direction. Furthermore, as in the third case, due to the wider spacing of the supply ports 258, a cell is formed by four or more drive elements. Therefore, electrodes can be shared in the boundary portions between cells, and thus the expansion of the drive element region can be suppressed.

[0135] <First Comparative Example>

[0136] Figure 15 This is a diagram illustrating an example arrangement of the heater and drive element in the first comparative example. Figure 15 The illustration shows an example in which a jet heater RhA is arranged, but a circulating heater RhB is not arranged. The jet heaters RhA are arranged at a density of 600 dpi to form jet heater row 201. Jet drive elements MD21 are arranged at the same density of 600 dpi as the jet heaters RhA, forming jet drive element row 1204. Jet drive element row 1204 is arranged parallel to jet heater row 201.

[0137] <Second Comparative Example>

[0138] Figure 16 This is a diagram illustrating an example arrangement of the heaters and drive elements in the second comparative example. The jet heaters RhA are arranged at a density of 600 dpi to form jet heater row 201. The circulating heaters RhB are arranged at the same density as the jet heaters RhA and form circulating heater row 202. The jet heaters RhA are electrically connected to the jet drive element MD11 via a wiring layer 1216. The circulating heaters RhB are electrically connected to the circulating drive element MD12 via a wiring layer 1218. In the case where the printed element substrate 300 is formed using a less expensive manufacturing process, it is not preferable to further provide an electrical connection wiring layer as an additional layer besides the conductive layer for extracting each electrode of the jet drive element MD11 and the circulating drive element MD12. That is, it is preferable to form the conductive layers in the jet drive element MD11 and the circulating drive element MD12, as well as the wiring layers 1216 and 1218, on the same layer and in the same manufacturing step. Figure 16In the example, a drive element row 1203 is formed, in which multiple units, each including a jet drive element MD11 and a circulation drive element MD12, are arranged. In drive element row 1203, the drive elements are arranged at a density of 1200 dpi, twice the arrangement density of the jet heater RhA. In the arrangement configuration described above, wiring layers 1216 and 1218 can be wired on the same layer. However, compared to the first comparative example, in the second comparative example, twice the number of drive elements are arranged in the row length direction. Therefore, the size of each drive element in the row length direction is half the size of the first comparative example. Therefore, in Figure 14 The example illustrates an instance in which the dimension in the line width direction is twice that in the second comparative example, so that the area of ​​the drive element is the same as that of the drive element in the first comparative example, in order to ensure the drive capability of the same drive current flowing through the injection drive element MD11 as in the first comparative example.

[0139] On the other hand, the driving current of the circulating heater RhB can generate heat energy to circulate the ink in the separate flow path 23. Furthermore, when the driving current of the circulating heater RhB is less than the driving current of the jet heater RhA, the current driving capability of the circulating drive element MD12 may be less than that of the jet drive element MD11. Therefore, it is preferable that the area of ​​the circulating drive element MD12 is smaller than the area of ​​the jet drive element MD11. However, in the second comparative example, the jet drive element MD11 and the circulating drive element MD12 are arranged with the same area. Therefore, the excessive element size of the circulating drive element MD12, as the printing element substrate 300, may lead to increased costs.

[0140] <Details of wiring configuration; Case 1>

[0141] Figure 17 This is a magnified example diagram illustrating the driving element in the first case. Figure 17In this example, injection drive elements MD1 and MD2, and cycle drive elements MD3 and MD4 are illustrated as driving elements. In injection drive element MD1, a gate electrode 221, a source electrode 212, and a drain electrode 216 are provided. In injection drive element MD2, a gate electrode 222, a source electrode 213, and a drain electrode 217 are provided. Source electrodes 212 and 213 are at the same potential. Furthermore, source electrodes 212 and 213 partially share and use electrodes in a shared ground electrode 209, and are connected to a ground wire GNDH on another layer via a via VIA. In other words, source electrodes 212 and 213 are electrically connected to each other in the shared ground electrode 209, which is a shared region. Since the shared ground electrode 209, as a shared region, is electrically connected to the ground wire, injection drive elements MD1 and MD2 are at a stable reference potential. It should be noted that although the drain electrode 216 and drain connection 216 are indicated by the same reference numerals, they are at the same potential, and in this embodiment, these terms are used differently depending on whether the viewpoint is electrode or connection. The same applies to the drain electrode 217 and drain connection 217.

[0142] In the cyclic drive element MD3, a gate electrode 223, a source electrode 214, and a drain electrode 218 are provided. In the cyclic drive element MD4, a gate electrode 224, a source electrode 215, and a drain electrode 219 are provided. Source electrodes 214 and 215 are at the same potential. Furthermore, source electrodes 214 and 215 partially share and use electrodes in a shared ground electrode 210, and are connected to a ground wire GNDH on another wiring layer via a via VIA. In other words, source electrodes 214 and 215 are electrically connected to each other in the shared ground electrode 210, which is a shared region. Since the shared ground electrode 210, as a shared region, is electrically connected to the ground wire GNDH, the cyclic drive elements MD3 and MD4 are at a stable reference potential. Note that gate electrode 223 is electrically connected by wiring between the cells of jet drive elements MD1 and MD2. Similarly, gate electrode 224 is electrically connected by wiring between the cells of jet drive elements MD1 and MD2.

[0143] <Details of wiring configuration; alternative configuration for the first case>

[0144] Figure 18 This is an example of having a ratio Figure 17 A magnified example of a drive element with fewer grounding wires is shown in the diagram. For example, the current flowing in the circulating drive elements MD3 and MD4 is less than that in... Figure 17In the case of current flowing in the circulating drive elements MD3 and MD4, the shared ground electrode 210 can be electrically connected to the shared ground electrode 209 via wiring 225.

[0145] <Details of wiring configuration; second scenario>

[0146] Figure 19 This is a magnified example diagram illustrating the driving element in the second case. Figure 19 In this embodiment, injection drive elements MD1 and MD2, and circulation drive elements MD5 and MD6 are illustrated as driving elements. In injection drive element MD1, a gate electrode 221, a source electrode 212, and a drain electrode 316 are provided. In injection drive element MD2, a gate electrode 222, a source electrode 213, and a drain electrode 317 are provided. Source electrodes 212 and 213 are at the same potential. Furthermore, source electrodes 212 and 213 partially share and use electrodes in a shared ground electrode 209, and are connected to a ground wire GNDH on another wiring layer via a via VIA. It should be noted that although drain electrode 316 and drain wiring 316 are indicated by the same reference numerals, they are at the same potential, and in this embodiment, these terms are used differently depending on whether the viewpoint is electrode or wiring. The same applies to drain electrode 317 and drain wiring 317.

[0147] In the cyclic drive element MD6, a gate electrode 323, a source electrode 314, and a drain electrode 318 are provided. In the cyclic drive element MD5, a gate electrode 324, a source electrode 315, and a drain electrode 319 are provided. Source electrodes 314 and 315 are at the same potential. Furthermore, in... Figure 19 Since source electrodes 314 and 315 are located in different cells, they do not share electrodes. Therefore, due to the extra space created between cells, drain wires 316 and 317 are wired. Furthermore, a shared ground electrode 310 is provided in the same cell. Note that gate electrode 323 is electrically connected by wiring between the cells of injection drive elements MD1 and MD2. Similarly, gate electrode 324 is electrically connected by wiring between the cells of injection drive elements MD1 and MD2.

[0148] <Details of the wiring configuration; another configuration for the second scenario>

[0149] Figure 20 This is an example of having a ratio Figure 19 A magnified example of a drive element with fewer grounding wires is shown in the diagram. For example, the current flowing in the circulating drive elements MD5 and MD6 is less than that in... Figure 19When current flows in the circulating drive elements MD5 and MD6, the shared ground electrode 310 can be electrically connected to the shared ground electrode 209 via wiring 325.

[0150] <Details of wiring configuration; Second comparative example>

[0151] Figure 21 This is an enlarged example illustration of the driving element in the second comparative example. The jet driving element MD11 and the circulation driving element MD12 are formed by repeating patterns of source electrodes 1212 and 1214 and drain electrodes 1216 and 1218 along the row length direction. Therefore, in the row length direction, there is little room for flexibly reducing the area of ​​the circulation driving element MD12. On the other hand, in the row width direction, there is room for flexibly reducing the area of ​​the circulation driving element MD12. Specifically, there is room for flexibly reducing the area of ​​the source electrode 1214, the drain electrode 1218, and the gate electrode 1223. However, the area resulting from reducing the area along the row width direction does not contribute to the size reduction of the printed element substrate 300. It should be noted that although the wiring layer 1216 and the drain electrode 1216 are indicated by the same reference numerals, they are electrically connected and at the same potential, and are used in different ways depending on the wiring of the wiring and the view of the extraction unit of the electrode of the driving element.

[0152] <Details of wiring configuration; cross-sectional structure>

[0153] Figure 22 This is an example along Figures 17 to 20 A diagram illustrating the cross-sectional structure taken from line XXII-XXII. (See diagram.) Figure 22 As illustrated, in the semiconductor substrate 110, a P-well region 101 and N-well regions 102a and 102b are formed on a P-type silicon substrate 100. The impurity concentrations of the N-well regions 102a and 102b relative to the P-type silicon substrate 100 are such that the breakdown voltages of the N-well regions 102a and 102b and the P-type silicon substrate 100 are higher than the voltage applied to the power line VH.

[0154] The impurity concentrations in P-well region 101 and N-well regions 102a and 102b are such that the breakdown voltage of P-well region 101 and N-well regions 102a and 102b is higher than the voltage applied to the power line VH. A field oxide film 103, a high-concentration N-type diffusion region 106, and a high-concentration P-type diffusion region 107 are formed in P-well region 101 and N-well regions 102a and 102b. For example, the field oxide film 103 can be formed by the localized oxidation of silicon (LOCOS) method.

[0155] (Configuration of injection drive elements MD1 and MD2)

[0156] The configuration of the injection drive elements MD1 and MD2 is described. Figure 19 The illustration shows an example in which jet driving elements MD1 and MD2 are each formed from a high-voltage NMOS transistor. Gate electrodes 221 and 222 are disposed on adjacent P-well regions 101 and N-well regions 102a and 102b via gate insulating film 104. The region of P-well region 101 overlapping with gate electrodes 221 and 222 is a channel formation region.

[0157] The high-concentration N-type diffusion region 106 is the source electrode of the jet driving elements MD1 and MD2. The high-concentration P-type diffusion region 107 is the back gate electrode of the jet driving elements MD1 and MD2. The back gate electrodes of the jet driving elements MD1 and MD2 are at the same potential as the substrate contacts 220 of the jet driving elements MD1 and MD2. The substrate contacts 220 are connected to the ground line GNDH via a wiring layer. Therefore, the high-concentration P-type diffusion region 107 is electrically connected to the ground line GNDH, and a reference potential is determined. The N-well regions 102a and 102b each include a portion extending below the portion located below each of the gate electrodes 221 and 222, serving as an electric field reduction region for the drain electrode. The high-concentration N-type diffusion region 106 formed in the N-well regions 102a and 102b is the drain electrode of the jet driving elements MD1 and MD2. Furthermore, the drain sides of gate electrodes 221 and 222 have a structure mounted on a field oxide film 103 formed in the N-well regions 102a and 102b, which is a so-called LOCOS offset structure. Therefore, gate-drain voltage protection can be ensured even when the jet driving elements MD1 and MD2 are in the off state (that is, the voltage of the gate electrode is GND) and the voltage of the drain electrode rises to the voltage applied to the power supply line VH.

[0158] The gate insulating film 104 can be formed during the manufacturing steps of the semiconductor substrate 110. For example, the gate insulating film 104 can be formed from an oxide film. Furthermore, the gate electrodes 221 and 222 can be, for example, polysilicon layers. The polysilicon layers, the high-concentration N-type diffusion region 106, and the high-concentration P-type diffusion region 107 can be formed in the same steps as the steps of forming each of the jet driving elements MD1 and MD2 to form a low-voltage protection logic circuit.

[0159] An insulating film is formed on the high-concentration P-type diffusion region 107, the high-concentration N-type diffusion region 106, and the field oxide film 103, and a plurality of contact units 108 are formed in the insulating film. Conductive layers 212, 213, 216, 217, and 220 are formed on the insulating film. Each of the conductive layers 212, 213, 216, 217, and 220 can be formed from a metal such as aluminum, for example. It should be noted that the manufacturing method, materials, and structure are not limited as long as the conductive layers, each electrode, and the wiring are electrically connected. It should be noted that although the conductive layer 212 and the source electrode 212 are indicated by the same reference numerals, they are both electrically connected and at the same potential, and are used in different ways depending on factors such as the cross-sectional structure and the function of the extraction unit that extracts the electrode from the driving element. The same applies to the conductive layer 213 and the source electrode 213. The same applies to the wiring 216, the conductive layer 216, and the drain electrode 216. This also applies to drain connection 217, conductive layer 217, and drain electrode 217. This also applies to drain connection 218 and drain electrode 218. This also applies to drain connection 219 and drain electrode 219. This also applies to conductive layer 220 and substrate contact 220. This also applies to conductive layer 221 and gate electrode 221.

[0160] Here, the source electrodes of jet driving elements MD1 and MD2 share the P-well region 101, the high-concentration N-type diffusion region 106, the contact unit 108, and the conductive layer 221 via a shared ground electrode 209. When jet driving element MD1 is in the on-state, a conduction potential is applied to the gate electrode 221, and current flows from the conductive layer 216 on the drain electrode side to the shared ground electrode 209. On the other hand, when jet driving element MD2 is in the on-state, a conduction potential is applied to the gate electrode 222, and current flows from the conductive layer 217 on the drain current side to the shared ground electrode 209. In this embodiment, although an example of the cross-section of jet driving elements MD1 and MD2 has been described, the cyclic driving elements MD3 and MD4 have a similar cross-sectional structure and include a shared ground electrode 210. In the case of the cross-sectional structure of cyclic driving elements MD3 and MD4, compared with... Figure 19 Unlike the illustration, the substrate contacts 220 are not arranged on both sides, and the drain wires 216 and 217 to the jet drive elements MD1 and MD2 are arranged on both sides.

[0161] It should be noted that although an example is described in this embodiment, in which shared ground electrodes 209 and 210 are provided while the source electrodes of the injection drive elements MD1 and MD2 and the circulation drive elements MD3 and MD4 are at the same potential, it is not particularly limited to this. For example, a configuration can be applied in which the drain electrode sides of the injection drive elements MD1 and MD2 and the circulation drive elements MD3 and MD4 are commonly connected to the power line VH, and each source electrode side is connected to the injection heater RhA and the circulation heater RhB. Next, refer to Figure 23 Another circuit configuration example of the printed element substrate 300 according to this embodiment is described.

[0162] <Another circuit configuration example>

[0163] Figure 23 This is a diagram illustrating another circuit configuration example of a printed element substrate according to this embodiment. Figure 23 The example is illustrated below, in which... Figure 11 The configuration of the jet heaters is arranged in two rows in a point-symmetric manner relative to the center of the printing element substrate 300. The group selection signal line 306 and the time-division selection signal line 307 are arranged parallel to the jet drive element row 203. Although the control data supply circuit 305 is arranged close to the external connection terminal row 309, the control data supply circuit 305 can be arranged parallel to the group selection signal line 306 along the row length direction. Although the two rows of jet heaters 201 arranged on the right and left sides of the centrally located printing element substrate 300 are arranged such that their coordinates in the row direction are shifted by half a pitch relative to the heater pitch, their coordinates in the row length direction can coincide with each other.

[0164] Although a description has been provided above illustrating various examples and embodiments of this disclosure, the intent and scope of this disclosure are not limited to the specific descriptions herein. This disclosure is not limited to the embodiments described above, and various modifications are applicable. Furthermore, this disclosure may be a suitable combination of some of the embodiments described above.

[0165] (Variation 1)

[0166] For example, although an example of using a via (VIA) for electrical connection to another wiring layer is described in this embodiment, it is not particularly limited thereto. For example, instead of a via (VIA) that allows conductivity between one wiring layer and another of a plurality of laminated wiring layers, a through-hole that allows conductivity between all wiring layers may also be used.

[0167] Other embodiments

[0168] Embodiments of the present invention can also be implemented by a computer that reads and executes computer-executable instructions (e.g., one or more programs) recorded on a storage medium (which may also be more fully referred to as a "non-transitory computer-readable storage medium") to perform the functions of one or more embodiments of the above embodiments and / or includes one or more circuits (e.g., application-specific integrated circuits (ASICs)) for performing the functions of one or more embodiments of the above embodiments, and by methods executed by the computer of the system or device, for example, by reading and executing computer-executable instructions from the storage medium to perform the functions of one or more embodiments of the above embodiments and / or controlling one or more circuits to perform the functions of one or more embodiments of the above embodiments. The computer may include one or more processors (e.g., a central processing unit (CPU), a microprocessor unit (MPU)) and may include a network of individual computers or individual processors to read and execute computer-executable instructions. The computer-executable instructions may be provided to the computer, for example, from a network or a storage medium. The storage medium may include one or more of, for example, a hard disk, random access memory (RAM), read-only memory (ROM), the memory of a distributed computing system, an optical disc (such as an optical disc (CD), a digital versatile optical disc (DVD), or a Blu-ray disc (BD)™), a flash memory device, a memory card, etc.

[0169] Other embodiments

[0170] The embodiments of the present invention can also be implemented by the following method: providing software (including computer program products of computer programs) that performs the functions of the above embodiments to a system or device via a network or various storage media, and the computer (central processing unit (CPU) or microprocessor unit (MPU) of the system or device) reads and executes the computer program.

[0171] While this disclosure has been described with reference to embodiments, it should be understood that this disclosure is not limited to the disclosed embodiments. The scope of the appended claims is to be given the broadest interpretation in order to cover all such modifications and equivalent structures and functions.

[0172] According to this disclosure, driving elements can be appropriately arranged on a printed element substrate.

Claims

1. A printed component substrate, comprising: A first row of heating resistor elements, the first row of heating resistor elements including a plurality of first heating resistor elements arranged in a row; The second row of heating resistor elements includes a plurality of second heating resistor elements arranged in a row parallel to the first row of heating resistor elements, the plurality of second heating resistor elements being different from the plurality of first heating resistor elements; A first drive element row, the first drive element row including a plurality of first drive elements arranged in a row to drive the plurality of first heating resistor elements; the plurality of drive elements are arranged to drive the plurality of heating resistor elements. as well as The second drive element row includes a plurality of second drive elements arranged in a row parallel to the first drive element row to drive the plurality of second heating resistor elements. These second drive elements are different from the plurality of first drive elements. The distance between the centers of gravity of two adjacent first driving elements in the plurality of first driving elements is less than the distance between the centers of gravity of two adjacent first heating resistor elements in the plurality of first heating resistor elements, and the distance between the centers of gravity of two adjacent second driving elements in the plurality of second driving elements is less than the distance between the centers of gravity of two adjacent second heating resistor elements in the plurality of second heating resistor elements.

2. The printed element substrate according to claim 1, wherein... The first heating resistor element acts as a jet heater to generate energy to jet the liquid from the liquid nozzle; and The second heating resistor element acts as a circulating heater to generate energy to circulate the liquid in the liquid jet head.

3. The printed element substrate according to claim 2, further comprising: A plurality of first drive units, wherein the plurality of first drive units are formed by two or more adjacent first drive elements among the respective plurality of first drive elements; A plurality of second drive units, wherein the plurality of second drive units are formed by two or more adjacent second drive elements among the respective plurality of second drive elements; as well as Multiple first wires are configured to electrically connect the multiple first drive units and the multiple first heating resistor elements, wherein... The plurality of heating resistor elements are positioned relative to the second driving unit on one side of the row width direction, which is orthogonal to the row length direction of the row of the second driving elements. The position of the first driving unit relative to the second driving unit is arranged on the other side of the row width direction, which is orthogonal to the row length direction of the second driving element row, and The plurality of first wires are configured to be wired between the plurality of second drive units.

4. The printed element substrate according to claim 3, further comprising: Multiple second wiring terminals are configured to electrically connect the multiple second drive units and the multiple second heating resistor elements, wherein... The second wiring is formed on the same layer as the first wiring.

5. The printed element substrate according to claim 3, wherein... In the first driving unit, the source electrodes of the two first driving elements on their adjacent sides are electrically connected to each other in a shared region, and The shared area is electrically connected to the grounding wire.

6. The printed element substrate according to claim 3, wherein... In the second driving unit, the source electrodes of the two second driving elements on their adjacent sides are electrically connected to each other in a shared region, and The shared area is electrically connected to the grounding wire.

7. The printed element substrate according to claim 2, wherein... The component area of ​​the first driving element is larger than the component area of ​​the second driving element.

8. The printed element substrate according to claim 2, wherein The driving current of the first heating resistor element is greater than the driving current of the second heating resistor element.

9. The printed element substrate according to claim 3, wherein The gate electrode of the second driving element is electrically connected between the first driving units by wiring.

10. The printed element substrate according to claim 1, wherein... The center of gravity of the second driving element is located on an imaginary extension line, which extends from the center of gravity of the first driving element along a line width direction orthogonal to the line length direction of the first driving element.

11. The printed element substrate according to claim 1, wherein The center of gravity of the second driving element is not located on the imaginary extension line, which starts from the center of gravity of the first driving element and runs along the line width direction orthogonal to the line length direction of the first driving element.

12. The printed element substrate according to claim 5, wherein The grounding wire is included in a grounding layer, which is disposed on a different layer from the layer on which the source electrode of the first driving element is formed, and the grounding wire is electrically connected to the source electrode through a via.

13. The printed element substrate according to claim 6, wherein The grounding wire is included in a grounding layer, which is disposed on a different layer from the layer on which the source electrode of the second driving element is formed, and the grounding wire is electrically connected to the source electrode through a via.

14. The printed element substrate according to claim 4, further comprising: A first supply port row, the first supply port row including a plurality of first supply ports arranged in a row for supplying ink; as well as The second supply port row includes a plurality of second supply ports arranged in a row parallel to the first supply port row for supplying ink, wherein The first row of heating resistor elements and the second row of heating resistor elements are arranged between the first row of supply ports and the second row of supply ports, and The second supply port row is arranged parallel to the second drive element row and is arranged closer to the second drive element row than the first drive element row.

15. The printed element substrate according to claim 14, wherein The first and second wirings are arranged to be wired between the respective second supply ports.

16. The printed element substrate according to claim 4, wherein The first driving element, the second driving element, the first wiring and the second wiring are formed in the same semiconductor manufacturing step.

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