Printed element substrate

Abstract

A print element substrate includes a heating resistor element group in which heating resistor elements are arranged, and a drive element group in which drive elements configured to drive the heating resistor elements are arranged in a region on the same layer as a heating element region. The drive element group includes a first drive element array in which first drive elements are arranged in an array in a first region of the drive element region, a second drive element array in which second drive elements different from the first drive elements are arranged in an array in a second region of the drive element region in parallel with the first drive element array, and one or more inter-array wiring layers arranged between the first drive element array and the second drive element array on the same layer and shared by the first drive elements and the second drive elements.

Description

Technical Field

[0001] This disclosure relates to a technique for arranging drive elements in a printed element substrate. Background Technology

[0002] A circulating liquid jetting device is conventionally known, which circulates ink within a liquid jetting head. Japanese Patent Application Publication No. 2020-104493 discloses a configuration as a circulating liquid jetting device, which includes a jetting energy generating element for jetting ink and a circulation energy generating element for circulating the ink. Furthermore, the circulating liquid jetting device uses drive elements for driving the jetting energy generating element and the circulation energy generating element, respectively. Summary of the Invention

[0003] A printed element substrate according to one aspect of the present disclosure includes: a group of heating resistor elements, the group of heating resistor elements having a plurality of heating resistor elements arranged thereon; and a group of driving elements, the group of driving elements having a plurality of driving elements configured to drive the plurality of heating resistor elements arranged in a region on the same layer as a heating element region having the plurality of heating resistor elements arranged thereon, wherein the group of driving elements includes: a first driving element array, the first driving element array including a plurality of first driving elements arranged in an array in a first region of the driving element region having the plurality of driving elements arranged thereon; a second driving element array, the second driving element array including a plurality of second driving elements different from the plurality of first driving elements, the plurality of second driving elements being arranged in an array side by side with the first driving element array in a second region of the driving element region; and one or more inter-array wiring layers, the one or more inter-array wiring layers being arranged on the same layer between the first driving element array and the second driving element array, the inter-array wiring layers being shared by the first driving elements and the second driving elements.

[0004] The features of this disclosure will become clear from the following description of embodiments with reference to the accompanying drawings. The following description of the embodiments is given by way of example. Attached Figure Description

[0005] Figure 1A This is a perspective view schematically showing a liquid jetting device in which the ink tank is positioned as a liquid reservoir outside the liquid jetting head;

[0006] Figure 1B This is a perspective view schematically showing a liquid jetting device in which the ink tank 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 the image;

[0008] Figure 2B This diagram illustrates the case where four colors can be sprayed from a single liquid jet chip;

[0009] Figure 2C This diagram illustrates the case where two colors can be sprayed from a single liquid jet chip;

[0010] Figure 2D This diagram illustrates the case where the number of colors that can be sprayed by a single liquid spraying chip is one.

[0011] Figure 3A It is a plan view taken along the direction in which droplets are ejected from the nozzle of a single injection unit;

[0012] Figure 3B yes Figure 3A Sectional view of IIIB-IIIB;

[0013] Figure 3C yes Figure 3A The IIIB-IIIB cross-sectional view, showing the internal configuration of the substrate. Figure 3B Different sectional views are configured within the framework;

[0014] Figure 3D This is a diagram illustrating the flow of ink when the first energy-generating element is driven;

[0015] Figure 4A yes Figure 3A The cross-sectional view of the individual injection unit in the diagram is shown in section IIIB-IIIB, and is used to explain the generation and growth process of bubbles generated by heating the ink with a second energy generating element and causing the ink film to boil.

[0016] Figure 4B yes Figure 3A A cross-sectional view of the individual injection unit in section IIIB-IIIB, and a cross-sectional view used to explain the contraction process of bubbles generated by heating the ink with a second energy generating element and causing the ink film to boil.

[0017] Figure 4C yes Figure 3A The cross-sectional view of the individual injection unit in the diagram is IIIB-IIIB, and is used to explain the process after the bubbles generated by heating the ink with a second energy generating element and causing the ink film to boil disappear.

[0018] Figure 5A This is a diagram showing the state where the ink circulation flow has temporarily stopped;

[0019] Figure 5B It is shown in Figure 5AThe diagram shows the state immediately following the state after the generation of the ink circulation flow by driving the second energy generating element;

[0020] Figure 5C It is shown in Figure 5B The diagram shows the state after which the ink circulation temporarily stops;

[0021] Figure 5D It is shown in Figure 5C The diagram shows the state immediately following the state after the generation of the ink circulation flow by driving the second energy generating element;

[0022] Figure 6A This is a diagram showing the state where the ink circulation flow has temporarily stopped;

[0023] Figure 6B It is shown in Figure 6A The diagram shows the state immediately following the state after the generation of the ink circulation flow by driving the second energy generating element;

[0024] Figure 6C It is shown in Figure 6B The diagram shows the state after which the ink circulation temporarily stops;

[0025] Figure 6D It is shown in Figure 6C The diagram shows the state immediately following the state after the generation of the ink circulation flow by driving the second energy generating element;

[0026] Figure 7A It is a plan view taken along the direction in which droplets are ejected from the injection orifice 11;

[0027] Figure 7B yes Figure 7A Sectional view of VIIB-VIIB;

[0028] Figure 7C yes Figure 7A An enlarged schematic diagram of a single channel in the image;

[0029] Figure 8A It is a plan view taken along the direction in which droplets are ejected from the injection orifice 11;

[0030] Figure 8B yes Figure 8A Sectional view of VIIIB-VIIIB;

[0031] Figure 8C yes Figure 8A VIIIB-VIIIB cross-sectional view, and the configuration inside the substrate 18 therein. Figure 8B Different sectional views are configured within the framework;

[0032] Figure 9AIt is a plan view taken along the direction in which droplets are ejected from the injection orifice 11;

[0033] Figure 9B yes Figure 9A IXB-IXB sectional view;

[0034] Figure 9C yes Figure 9A The IXB-IXB cross-sectional view, and the configuration inside the substrate 18 therein. Figure 9B Different sectional views are configured within the framework;

[0035] Figure 10 This is a diagram illustrating an example of the circuit configuration of a printed element substrate according to this embodiment;

[0036] Figure 11 This is a diagram illustrating an example arrangement of the heater and drive element according to a first case of this embodiment;

[0037] Figure 12 This is a diagram illustrating an example arrangement of the heater and drive element according to a second case of this embodiment;

[0038] Figure 13 This is a diagram illustrating an example arrangement of the heater and drive element in the first comparative example;

[0039] Figure 14 This is a diagram illustrating an example arrangement of the heater and drive element in the second comparative example;

[0040] Figure 15 This is a diagram illustrating an example arrangement of the heater and drive element in a third case according to this embodiment;

[0041] Figure 16 This is a diagram showing an enlarged example of the driving element in the first case;

[0042] Figure 17 This is a diagram showing an enlarged example of the driving element in the second case;

[0043] Figure 18 This is a diagram showing an enlarged example of the driving element in the second comparative example;

[0044] Figure 19 It shows along Figure 16 and Figure 17 A cross-sectional view of the XIX-XIX line in the diagram; and

[0045] Figure 20 This is a diagram illustrating another example of a circuit configuration for a printed element substrate according to this embodiment. Detailed Implementation

[0046] Preferred embodiments of the present disclosure are explained in detail below with reference to the accompanying drawings. It should be noted that the following embodiments do not limit the subject matter of the present disclosure, and not all combinations of features explained in the following embodiments are necessary to solve the problems of the present disclosure. Note that the same constituent elements are denoted by the same reference numerals.

[0047] (Overview)

[0048] Liquid jet heads typically already possess the function of circulating ink to expel air bubbles from the ink channel and suppress ink thickening near the jet orifice. Liquid jetting equipment equipped with liquid jet heads possessing this function is called a circulating liquid jetting equipment. Furthermore, the method of using a pressure difference (hereinafter also referred to as the pressure difference method) for ink circulation is well known. In the pressure difference method, the pressure on the ink supply side (inlet side) of each jet orifice is set higher than the pressure on the ink recovery side (outlet side) of the jet orifice by using a pressure regulating mechanism. Therefore, ink flows from the inlet side to the outlet side. Furthermore, to facilitate ink circulation, it is preferable to return the ink flowing to the outlet side to the inlet side. Therefore, a pump is provided. Note that there are configurations where the pump is located outside the liquid jet head within the body of the liquid jetting equipment, thereby circulating ink between the liquid jet head and the body of the liquid jetting equipment. There are also configurations where the pump is located inside the liquid jet head, thereby circulating ink within the liquid jet head. However, in the pressure difference method, due to the presence of the pressure regulating mechanism and the pump, the size of the liquid jetting equipment body and the liquid jet head tends to be relatively large.

[0049] Therefore, methods for ink circulation other than the pressure difference method have also been investigated. Specifically, there exists a configuration in which a circulation channel is provided in communication with the jet orifice, and an energy generating element (hereinafter referred to as a circulation energy generating element) different from the energy generating element for jetting ink (hereinafter also referred to as the jetting energy generating element) is provided in this circulation channel. This configuration allows ink to circulate in the circulation channel by driving the circulation energy generating element.

[0050] An array of jet energy generating elements and an array of circulating energy generating elements are known to be arranged side-by-side. In this configuration, the circulating energy generating elements are mounted in pairs with their corresponding jet energy generating elements. Therefore, both the jet energy generating elements and the circulating energy generating elements are manufactured to be electrically connected to the driving element and the ground wire. Furthermore, when forming the printed element substrate using a low-cost manufacturing process, it is preferable not to provide an electrical connection wiring layer as a separate layer, except for the conductive layer used to lead out the electrodes of the driving elements. Specifically, in a low-cost manufacturing process, it is preferable that the conductive layer and the wiring layer are formed from the same layer and in the same manufacturing step. Furthermore, when the magnitude of the driving current of the jet driving element differs from that of the circulating driving element, arranging the driving elements as driving elements with the same shape (i.e., driving elements with the same current driving performance) in an array is not preferred due to excess weight. Specifically, when both the circulating and jet driving elements are formed to the same size, even though the driving current of the circulating driving element is smaller than that of the jet driving element, the excessively large element size of the circulating driving element may lead to an increase in the area of ​​the printed element substrate and high cost.

[0051] The printed element substrate disclosed herein therefore includes a group of heating resistor elements and a group of driving elements. In the group of heating resistor elements, a plurality of heating resistor elements are arranged. In the group of driving elements, a plurality of driving elements configured to drive the plurality of heating resistor elements are arranged in a region on the same layer as the heating element region where the heating resistor elements are arranged. The group of driving elements includes a first driving element array, a second driving element array, and an inter-array wiring layer. In the first driving element array, first driving elements are arranged in an array in a first region of the driving element region, which is the region where the driving elements are arranged. In the second driving element array, second driving elements, different from the first driving elements and arranged parallel to the first driving element array, are arranged in an array in a second region of the driving element region. The inter-array wiring layer is arranged on the same layer between the first and second driving element arrays and is shared by the first and second driving elements. According to this configuration, gap spaces are formed in the region where the driving elements are arranged due to the presence of the inter-array wiring layer. Therefore, wiring connecting the driving elements and heating resistor elements to each other can be routed in the gap spaces. Enabling wiring allows for the placement of a conductive layer and a wiring layer on the same layer. Therefore, the driving elements can be appropriately arranged in the printed element substrate.

[0052] For example, suppose an array of driving elements configured to drive jet energy generating elements and an array of driving elements configured to drive circulating energy generating elements are arranged in two parallel arrays. Furthermore, in this case, suppose the element size of the driving elements configured to drive jet energy generating elements is different from the element size of the driving elements configured to drive circulating energy generating elements. Moreover, in each of the two arrays of driving elements, two adjacent driving elements are arranged close to each other to form a cell. As described above, arranging the driving elements close to each other in each cell creates gap spaces between the driving elements. Routing ground lines and electrical connection wiring in these gap spaces allows the wiring layer and conductive layer in the closely arranged driving elements to be arranged in the same layer. In the case where the driving element is a field-effect transistor, the conductive layer is the layer where the source electrode, gate electrode, and drain electrode are electrically connected to each other. The wiring layer is the layer from which wiring from the driving elements to the jet energy generating elements and the circulating energy generating elements is led out. Furthermore, when jet energy generating elements and circulating energy generating elements are arranged adjacent to the array of driving elements in an orthogonal direction, the elements can share a ground terminal (source wiring) connected to the source electrode in the array direction of the driving elements and be connected to a common ground wire. In this connection configuration, the size of the area including the lead-out portion of the ground terminal of each driving element can be reduced.

[0053] <Liquid Jetting Equipment 50>

[0054] Figure 1A and Figure 1B This is a diagram showing an example of the overall configuration of the liquid injection device 50. Figure 1A This is a schematic perspective view of a liquid jetting device 50, in which the ink tank 2 is disposed outside the liquid jetting head 1 as a liquid reservoir. Figure 1B This is a schematic perspective view of the liquid jetting device 50, in which the ink cartridge 54 is positioned directly above the liquid jetting head 1. First, regarding... Figure 1A and Figure 1B Explain the common parts.

[0055] 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 perform scanning in a direction X intersecting the transport direction Y of the target medium P. The liquid jetting head 1 is mounted in a carrier 60. The liquid jetting head 1 is fixed to and supported on the carrier 60 by a positioning device (not shown) and electrical contacts provided in the carrier 60. The carrier 60 reciprocates along a guide shaft 51 in the main scanning direction (also called direction X). Therefore, the liquid jetting head 1 jets ink while moving together with the carrier 60 in the main scanning direction, thereby performing printing on the target medium P. The transport rollers 55, 56, 57, and 58 transport the target medium P in a secondary scanning direction (also called the transport direction Y) intersecting (or orthogonal in this embodiment) with the main scanning direction. Specifically, the liquid jetting apparatus 50 is configured as a serial inkjet liquid jetting apparatus by jetting liquid from the liquid jetting head 1 to the target medium P transported in the transport direction Y while performing scanning in direction X by the liquid jetting head 1. It should be noted that the application of this disclosure is not limited to serial inkjet liquid ejection devices. This disclosure can also be applied to page-width inkjet liquid ejection devices that use a linear head (page-width head) that is elongated along the page-width direction of the ejection target medium P to eject liquid onto the target medium P being conveyed in the transport direction Y. Note that direction Z represents... Figure 1A and Figure 1B The vertical direction in the diagram. Specifically, direction Z is the direction that intersects (or is orthogonal in this embodiment) the XY plane specified by direction X and transmission direction Y.

[0056] 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 panchromatic 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 mentioned above. For example, this disclosure can also be applied to liquid ejector heads 1 configured to eject other types of ink (such as spot color inks). Specifically, the type and quantity of ink ejected from the liquid ejector head 1 are not limited.

[0057] Next, an explanation Figure 1A and Figure 1B The different parts. In Figure 1A In the liquid jetting head 1, an ink sub-tank 54 is installed. Four ink supply pipes (liquid communication paths) 59 are attached to the ink sub-tank 54. Furthermore, the liquid jetting device 50 includes an ink tank 2 and an external pump 71. The ink tank 2 stores ink. Driven by the external pump 71, the ink stored in the ink tank 2 is supplied to the ink sub-tank 54 via the four ink supply pipes 59. Meanwhile, in… Figure 1B In the middle, the ink tank 54 is positioned directly above the liquid injection head 1. Figure 1B and Figure 1AThe difference lies in the fact that, since there is no ink reservoir 2 outside the liquid jet head 1, there are no four ink supply pipes 59 attached, nor is there an external pump 71. Note that in Figure 1A and Figure 1B In either case, the liquid injection head 1 can be configured to be integrally mounted with the ink reservoir 54 and can be attached to or detached from the carrier 60. Alternatively, this configuration allows the ink reservoir 54 to be integrally mounted with the carrier 60, and only the ink reservoir 54 can be attached to or detached from the carrier 60. (This will be discussed in the context of use.) Figure 1A The following explanation is provided along with the configuration.

[0058] <Basic Configuration of Liquid Jet Head 1>

[0059] Figures 2A to 2D It is shown Figure 1A and Figure 1B A diagram showing a basic configuration example of the liquid injection head 1. Figure 2A yes Figure 1A and Figure 1B Exploded perspective view of liquid jet head 1 in the image. Figure 2B , Figure 2C and Figure 2D It is shown Figure 2A A diagram illustrating an example of a liquid ejection chip 3 is provided. The liquid ejection head 1 includes a housing portion 53, an ink reservoir 54, and a liquid ejection chip 3. The ink reservoir 54 temporarily stores ink from the liquid ejection head 1. The ink reservoir 54 is housed within the housing portion 53. As described in detail later, the liquid ejection chip 3 is disposed in the bottom portion of the housing portion 53. The liquid ejection chip 3 ejects ink supplied from the ink reservoir 54 onto the target medium P.

[0060] Note that, although omitted from the diagram, a liquid connector insertion port is provided on the wall surface of housing portion 53. Figure 1A A liquid connector located at the front end of the ink supply tube 59 is liquid-tightly inserted into and connected to these liquid connector insertion ports. This configuration forms an ink supply path extending from the ink tank 2 via the external pump 71 to the liquid ejector head 1. In this embodiment, four types of ink are used. Therefore, four sets of ink tanks 2, external pumps 71, ink supply tubes 59, and ink auxiliary tanks 54 are provided respectively for each type of ink. Thus, four ink supply paths corresponding to each type of ink are independently formed. As described above, in this embodiment, the liquid ejector device 50 includes an ink supply system in which ink is supplied from ink tanks 2 disposed outside the liquid ejector head 1.

[0061] A first support member 4 and a second support member 7 are disposed between the housing portion 53 and the liquid jet chip 3. An electrical wiring member 5 is disposed below the liquid jet chip 3. Specifically, the first support member 4 has an ink supply port and an ink recovery port. The second support member 7 has an opening. The liquid jet chip 3 is attached to and fixed to the first support member 4. The first support member 4 is attached to and fixed to the second support member 7. The second support member 7 holds the electrical wiring member 5, such that the electrical wiring member 5 is electrically connected to the liquid jet chip 3. The electrical wiring member 5 applies electrical signals to the liquid jet chip 3 for ink jetting and for ink circulation.

[0062] Note that in this embodiment, the liquid jetting device 50 does not include an ink recovery system for recovering ink from the liquid jetting head 1 to the ink tank 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 configured to recover ink to the ink tank 2.

[0063] Figure 2B The diagram shows a configuration where the liquid jetting chip 3 has one chip for every four colors. Specifically, Figure 2B The diagram illustrates a scenario where four colors can be ejected from a single liquid jet chip 3. The liquid jet chip 3 includes multiple jetting orifices and pads for electrical mounting. The four colors are, for example, black, cyan, magenta, and yellow, and arrays are arranged for each color. Each array is formed along the transport direction Y, and the arrays are spaced apart along the X direction. Each array includes multiple jetting orifices. The multiple jetting orifices are arranged at equal intervals along the Y direction. The jetting orifices in each array can be arranged as one array along the Y direction without being spaced apart in the X direction. Alternatively, this configuration allows for two arrays of jetting orifices for only black, three arrays for the other three colors, and a total of five arrays for all four colors. Note that... Figure 2A The liquid jet chip 3 illustrates an example configuration with one chip for each of the four colors. Specifically, Figure 2A The liquid jet chip 3 shows Figure 2B An example of the situation.

[0064] Figure 2C The diagram shows a configuration where the liquid jet chip 3 has one chip for every two colors. In this case, two chips are used. Specifically, Figure 2C This illustrates a scenario where two colors can be sprayed from a single liquid spray chip 3. When the liquid spray chip 3 is installed in the liquid spray head 1, two liquid spray chips 3 can be installed in one liquid spray head 1, or two liquid spray heads 1 can be prepared, each with one liquid spray chip 3 installed.

[0065] Figure 2D The diagram illustrates a configuration where the liquid jetting chip 3 has one chip for each color. In this case, four chips are used. Specifically, Figure 2D This illustrates a case where the number of colors that can be sprayed from a single liquid spray chip 3 is one. When the liquid spray chip 3 is installed in the liquid spray head 1, four liquid spray chips 3 can be installed in one liquid spray head 1, or four liquid spray heads 1 can be prepared, each with one liquid spray chip 3 installed.

[0066] Note that, assuming in Figure 2C and Figure 2D In the case shown where multiple liquid jetting chips 3 are installed in a single liquid jetting head 1, the liquid jetting chips 3 do not necessarily have to have the same chip length. Furthermore, the number of colors of the liquid jetting chips 3 is not limited to a specific number, and various combinations of color numbers can be used. For example, although described... Figure 2A The example of the liquid jet chip 3 has four colors, but the liquid jet chip 3 can have more than four colors.

[0067] <Single Channel: Linear>

[0068] The liquid injection head 1 includes multiple individual injection units with individual channels. The liquid injection head 1 also includes a supply channel for supplying liquid to the individual channels of each individual injection unit. Figure 3A , Figure 3B , Figure 3C and Figure 3D This is a diagram illustrating the portion near each injection orifice 11 of an individual injection unit, including a linear individual channel 23. Figure 3A It is a plan view taken along the direction in which droplets are ejected from the ejection orifice 11 of the individual ejection unit. Figure 3B yes Figure 3A Sectional view of IIIB-IIIB. Figure 3C yes Figure 3A The IIIB-IIIB cross-sectional view, and the configuration inside the substrate 18 therein. Figure 3B Different sectional views are configured within the same space.

[0069] Each individual injection unit includes an injection orifice 11, a pressure chamber 12, a first energy generating element 14 (also known as an injection energy generating element 14) and a second energy generating element 24 (also known as a circulating energy generating element 24).

[0070] Pressure chambers 12 corresponding to each injection orifice 11 are formed by dividing the space between the substrate 18 and the orifice plate 19 using a partition 21. An injection orifice 11 is an opening formed in a portion of the orifice plate 19. A meniscus of ink flowing through the pressure chamber 12 is formed in the injection orifice 11, and the injection orifice interface forms an interface between the ink and the atmosphere. Liquid is injected through the injection orifice 11.

[0071] The individual channel 23 extends in a second direction that intersects (or is orthogonal in this embodiment) the direction in which the injection orifices 11 are arranged in an array (first direction). The individual channel 23 includes a pressure chamber 12, an inlet (upstream) side connecting channel 13, and an outlet (downstream) side connecting channel. The inlet side connecting channel 13 communicates with one end portion of the pressure chamber 12. The outlet side connecting channel communicates with the other end portion of the pressure chamber 12.

[0072] A first supply opening 22 is provided on one end side of the individual channel 23. The first supply opening 22 is an opening that extends from a common channel (not shown) through the interior of the substrate 18 to the upstream side of the individual channel 23. A second supply opening 32 is provided on the other end side of the individual channel 23. The second supply opening 32 is an opening that extends from a common channel (not shown) through the interior of the substrate 18 to the downstream side of the individual channel 23. Liquid is supplied to the individual channel 23 via the first supply opening 22 and the second supply opening 32.

[0073] 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 for ejecting liquid from the pressure chamber 12 through the ejection orifice 11. Specifically, the first energy generating element 14 is driven to generate heat and cause the liquid (also referred to as ink) in the pressure chamber 12 to bubble. The first energy generating element 14 can thus generate energy by using this bubble to eject ink from the ejection orifice 11. In this embodiment, an electrothermal conversion element is used as the first energy generating element 14. However, the first energy generating element 14 is not limited to a specific element. For example, a piezoelectric element can be used as the first energy generating element 14.

[0074] 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 induce a circulating flow of ink in the individual channel 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, the second energy generating element 24 is not limited to a specific element. For example, a piezoelectric element can be used as the second energy generating element 24.

[0075] The explanation of "linear" is given below. "Linear" refers to the shape of the individual channel 23 being configured such that the two end portions of the individual channel 23 are located on either side of the injection orifice 11, and the direction passing through the two end portions of the individual channel 23 intersects the direction along the array of injection orifices 11 (in...). Figure 3A In the example, it extends in a direction orthogonal to the direction of the array along the jet orifice 11. In other words, in a separate channel 23, the first energy generating element 14 and the second energy generating element 24 are arranged in a direction intersecting the direction of the array along the jet orifice 11.

[0076] Furthermore, an inlet-side connection channel 13 is formed on the side of the second energy generating element 24. The inlet-side connection channel 13 is formed by a portion of the first supply opening 22 and the separate channel 23 on the side of the second energy generating element 24. Simultaneously, an outlet channel is formed on the side of the first energy generating element 14. The outlet channel is formed by another portion of the second supply opening 32 and the separate channel 23 on the side of the first energy generating element 14.

[0077] Next, the flow of ink in the individual channel 23 will be explained. The flow of ink in the individual channel 23 is of two types. The first ink flow is a refill flow that occurs after the liquid jetting device 50 drives the first energy generating element 14 and ejects ink from the jetting orifice 11. The second ink flow is a circulating flow that occurs when the liquid jetting device 50 drives the second energy generating element 24 to generate a circulating flow in the direction of arrow 27.

[0078] <The First Ink Flow>

[0079] exist Figure 3D The diagram illustrates how the liquid jetting device 50 drives the first energy generating element 14 and ejects ink from the jetting orifice 11. Figure 3D This is a diagram illustrating the ink flow when the first energy-generating element 14 is driven. Figure 3D In the example where ink is ejected 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 into the pressure chamber 12 from both the first supply opening 22 and the second supply opening 32.

[0080] <Second Ink Flow>

[0081] Simultaneously, when the second energy generating element 24 is driven to generate a circulating flow, ink flows into the separate channel 23 through the first supply opening 22 and flows out of the separate channel 23 through the second supply opening 32. In this embodiment, the liquid jetting device 50 generates a circulating flow of ink in the separate channel 23 in the direction indicated by arrow 27 by causing the ink flowing out from the second supply opening 32 to return to the first supply opening 22 to circulate the ink. Figure 3CAn example is shown in which the first supply opening 22 and the second supply opening 32 become a common channel in the liquid jet chip 3. Figure 3D This is an example in which each of the first supply opening 22 and the second supply opening 32 is configured as a separate channel and the separate channels become a common channel outside the liquid injection head 1.

[0082] Let's further explain the ink circulation. Ink contains solid components and volatile components such as water. When using the liquid ejector head 1, there is a possibility of instability in ink ejection from the ejector orifice 11 due to the evaporation of volatile components from the ink at the ejector orifice 11, and the concentration increase of solid components in the ink near the ejector orifice 11 as the volatile components evaporate. Therefore, various efforts have been made to prevent instability in ink ejection from the ejector orifice 11.

[0083] For example, a cap member (not shown) can be provided in the X direction at a location outside the transport path of the target medium P. The cap member is shaped such that it can cover the surface of the liquid jet head 1 where the jet orifice 11 is provided. When the liquid jet head 1 is not performing a printing operation on the target medium P, the cap member can prevent the jet orifice 11 from drying out and protect the jet orifice 11 by covering the surface of the jet orifice 11 of the liquid jet head 1.

[0084] In addition, an ink suction mechanism (not shown) can be provided. When a cap member and an ink suction mechanism are provided, the cap member is used in conjunction with the operation of suctioning ink from the ejection orifice 11. Since the ink suction operation refreshes the ink near the ejection orifice 11, the image quality of the acquired image can be maintained.

[0085] 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-ejection (also known as pre-discharge). Additionally, a method is known in which an ejection operation called pre-ejection (also known as paper pre-ejection or in-page pre-ejection) is performed when the liquid ejector head 1 is performing a printing operation on the target medium P. Paper pre-ejection or in-page pre-ejection is an ejection operation that ejects a negligible amount of ink at a location on the target medium P that is inconspicuous in terms of image quality. Although these ejection operations greatly contribute to improving image quality, a portion of the ink is discarded to refresh the ejection orifice 11. Therefore, it is desirable to preferably minimize the amount of waste ink.

[0086] Therefore, a second energy generating element 24 for heating the ink in the individual channel 23 is provided in the substrate 18 to generate a circulating flow of ink. This circulating flow of ink can suppress the drying of the ejection orifice 11 and the ink concentration near the ejection orifice 11 while suppressing the amount of waste ink. From another perspective, the number of ink pre-ejections and ink suctions can be minimized. Furthermore, minimizing the number of ink pre-ejections can increase the throughput and output of the entire liquid ejection device 50. Note that the second energy generating element 24 can provide the above-mentioned effects by providing the second energy generating element 24 in at least some of the individual channels 23 included in the liquid ejection head 1.

[0087] also, Figure 1A The liquid ejector head 1 can be configured such that the second energy generating element 24 is disposed in all portions corresponding to four types of ink, or configured such that the second energy generating element 24 is disposed only in the portion corresponding to one type of ink. Specifically, the liquid ejector head 1 can be configured such that at least one of the multiple types of ink is circulated.

[0088] Note that, as Figure 3A The filter 31 shown can be disposed in the ink circulation channel to remove foreign matter contained in the ink. The filter 31 is a protrusion formed by a portion of the orifice plate 19 protruding toward the substrate 18. Figures 3A to 3D In the example, filter 31 is positioned at one end and the other end of each individual channel 23. In the ink circulation channel, one end of the individual channel 23 corresponds to the ink inflow side, and the other end of the individual channel 23 corresponds to the ink outflow side. Filter 31 can be positioned in the individual channel 23 between the first energy generating element 14 and the second energy generating element 24. When filter 31 is positioned in the individual channel 23 between the first energy generating element 14 and the second energy generating element 24, filter 31 is not necessarily positioned at one end and the other end of the individual channel 23. Next, using... Figures 4A to 4C To explain the principle behind ink circulation flow.

[0089] <Principle of Ink Circulation>

[0090] Figures 4A to 4C This diagram is used to explain the principle behind ink circulation flow. Figures 4A to 4C The illustration of filter 31 has been omitted to aid in explanation. Figure 4A yes Figure 3AThe cross-sectional view of the individual injection unit in section IIIB-IIIB is used to explain the generation and growth process of bubble B generated by heating the ink with the second energy generating element 24 and causing the ink film to boil. Figure 4B yes Figure 3A The cross-sectional view of the individual injection unit in the diagram is IIIB-IIIB, and is used to explain the contraction process of bubble B generated by heating the ink with the second energy generating element 24 and causing the ink film to boil. Figure 4C yes Figure 3A The diagram shows a cross-sectional view (IIIB-IIIB) of the individual injection unit, used to explain the process after the disappearance of bubble B, which is generated by heating the ink with the second energy generating element 24 and causing the ink film to boil. Next, the generation and growth process, contraction process, and subsequent process of bubble B will be explained.

[0091] <The generation and growth process of bubble B>

[0092] like Figure 4A As shown, the second energy generating element 24 is positioned closer to the first supply opening 22 within the first supply opening 22 and the second supply opening 32. Therefore, the flow resistance R1 generated in the channel between the second energy generating element 24 and the first supply opening 22 in response to the generation of a certain circulating amount of ink is less than the flow resistance R2 generated in the channel between the second energy generating element 24 and the second supply opening 32. Therefore, as... Figure 4A As shown, the difference between flow resistance R1 and flow resistance R2 causes bubbles B generated by film boiling of the ink to grow in the channel where flow resistance R1 is relatively smaller. Therefore, the flow vector Fa of the ink flowing towards the channel that generates flow resistance R1 is greater than the flow vector Fb of the ink flowing towards the channel that generates flow resistance R2. Note that the loop including flow resistances R1 and R2 is equivalent to a loop where the flow resistance generated by the circulating flow of ink in the channel including individual channel 23 is represented by analogy to resistance.

[0093] <The contraction process of bubble B>

[0094] During the contraction of bubble B, ink flows in to fill the volume corresponding to the contraction of bubble B. In this case, as... Figure 4B As shown, the flow vector Fc of ink flowing in from the first supply opening 22 on the flow resistance R1 side is greater than the flow vector Fd of ink flowing in from the second supply opening 32 on the flow resistance R2 side. Furthermore, the disappearance position of bubble B shifts from above the second energy generating element 24 to a portion of the channel closer to the second supply opening 32.

[0095] <The process after bubble B disappears>

[0096] Such as by using Figure 4B As explained, the relationship Fc > Fd is established. Therefore, a flow vector F is generated for the circulating flow of ink from the first supply opening 22 toward the second supply opening 32. The magnitude of the flow vector F is influenced 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, the arrangement of the second energy generating element 24 is preferably closer to one of the two end portions of the individual channel 23 than the arrangement of the first energy generating element 14. Specifically, the flow resistance ratio R1 / R2 is preferably set in the range of 0.05 to 0.40. Setting the flow resistance ratio R1 / R2 in the range of 0.05 to 0.40 allows the flow vector F of the circulating ink flow to be set to a local maximum. Increasing the ink flow vector Fa and increasing the ink flow vector Fc increases the flow vector F of the circulating ink flow and increases the circulating ink flow. Therefore, it is preferable to minimize the flow resistance R1 as much as possible. Furthermore, it is preferable to minimize the ink flow vector Fb and decrease the ink flow vector Fd as much as possible. Therefore, it is preferable to increase the flow resistance R2. Therefore, it is preferable to reduce the flow resistance R1 and increase the flow resistance R2. Specifically, reducing the flow resistance ratio R1 / R2 is preferred. Furthermore, a larger bubble B (i.e., a larger volume of bubble B) results in an increased fluid displacement volume in the individual channel 23, thereby increasing the circulation flow. For example, the following elements can be given as contributing factors to increased circulation flow: Elements contributing to increased circulation flow include increasing the size of the second energy generating element 24. Furthermore, elements contributing to increased circulation flow include increasing the width and height of the channel on the side of the first supply opening 22 and reducing the flow resistance R1 relative to the flow resistance R2. Furthermore, elements contributing to increased circulation flow include reducing the viscosity of the ink. Furthermore, elements contributing to increased circulation flow include increasing the temperature of the liquid ejector head 1. Furthermore, elements contributing to increased circulation flow include configuring the drive pulse as a dual-pulse. Configuring the drive pulse as a dual-pulse means the following: First, a short pulse is applied to the second energy generating element 24 to heat the ink around the portion of the channel above the second energy generating element 24, the short pulse having a level such that the pulse does not generate bubbles in the portion of the channel above the second energy generating element 24. Then, the main pulse that generates bubbles for ink circulation is applied to the second energy generating element 24 to grow large bubbles.

[0097] Furthermore, a portion of the ink flowing through the ink circulation flow enters the interior of the ejection orifice 11. This causes the concentrated ink in the ejection orifice 11 to be delivered to the channel on the side of the second supply opening 32, and causes fresh ink to flow into the ejection orifice 11 from the channel on the side of the first supply opening 22 through a separate channel 23. Therefore, the concentrated ink is less likely to stagnate in the ejection orifice 11. Thus, the initial ink ejection state can be maintained while suppressing the effect of concentrated ink.

[0098] The ink circulation flow is a transitional flow generated during the growth and contraction processes when bubble B is generated. Therefore, after bubble B disappears, the inertial circulation flow of the ink decays over time and stops after a certain period. Therefore, in order to generate a circulation flow periodically within a certain time period, it is preferable to repeatedly drive the second energy generating element 24. Note that the driving cycle of the second energy generating element 24 is not limited to a specific cycle, as long as the concentrated ink stagnating in the jet orifice 11 can be discharged. Note that the ink circulation flow is a transitional flow generated during the growth and contraction processes when bubble B is generated. Therefore, if the second energy generating element 24 is driven at a high driving frequency such as about 100 kHz, considering a cycle of 10 μs (i.e., the time period from the generation to the disappearance of bubble B), it is possible that phenomena hindering the promotion of ink circulation may occur. Therefore, it is preferable to drive the second energy generating element 24 with a driving cycle of, for example, about 100 Hz to tens of kHz.

[0099] Specifically, the higher the driving frequency of the second energy generating element 24, the better the ink circulation can be maintained. Therefore, the concentrated ink ejection effect, due to the increased ink circulation volume, is improved. However, assuming a higher driving frequency of the second energy generating element 24, the ink temperature rises more due to the heat generated by the second energy generating element 24 caused by its driving. Therefore, it is preferable to appropriately control the driving frequency of the second energy generating element 24. Next, by using... Figures 5A to 5D and Figures 6A to 6D This is to explain how ink concentration is eliminated through the circulation of ink.

[0100] <Elimination of ink concentration; linear>

[0101] Figures 5A to 5D This is a diagram illustrating how ink circulation eliminates concentration in a linear single channel 23. Figure 5A This is a diagram illustrating the state in which the ink circulation temporarily stops. Figure 5B This means that in Figure 5A The diagram shows the state immediately following the state after the second energy generating element 24 is driven to generate the ink circulation flow. Figure 5C This means that in Figure 5B This is a diagram illustrating a state where the ink circulation temporarily stops after the initial state. Figure 5DThis means that in Figure 5C The diagram illustrates the state immediately following the state after the second energy generating element 24 is driven to generate the ink circulation flow. (See diagram for example.) Figures 5A to 5D As shown, the linear individual channel 23 has a configuration where the inlet and outlet of the ink circulation flow are separated from each other. Note that the ink in the individual channel 23 is shaded with a dot pattern, and the density of the dot pattern shading is increased in the concentrated portion of the ink to indicate the degree of ink concentration.

[0102] like Figure 5A As shown, when the ink circulation is temporarily stopped, the volatile components of the ink evaporate from the injection orifice 11. Therefore, ink concentration progresses near the injection orifice 11. Then, by driving the second energy generating element 24, the ink circulation is restored. As a result, as... Figure 5B As shown, ink concentration that had progressed near the jet orifice 11 was eliminated. Then, in the case where the ink circulation flow was temporarily stopped, as... Figure 5C As shown, Figure 5A As before, ink concentration proceeds again near the injection orifice 11. Thereafter, the ink circulation is restored by driving the second energy generating element 24. As a result, as... Figure 5D As shown, Figure 5B In this way, ink concentration that progresses near the jet orifice 11 is eliminated. Therefore, ink concentration is eliminated throughout the entire individual channel 23. As described above, in the linear individual channel 23, the ink concentration state is reset each time the ink circulation flow is temporarily stopped and resumed.

[0103] <Elimination of ink concentration; U-shaped>

[0104] Figures 6A to 6D This is a diagram illustrating how ink circulation eliminates concentration in a U-shaped individual channel 23. Figure 6A This is a diagram illustrating the state in which the ink circulation temporarily stops. Figure 6B This means that in Figure 6A The diagram shows the state immediately following the state after the second energy generating element 24 is driven to generate the ink circulation flow. Figure 6C This means that in Figure 6B This is a diagram illustrating a state where the ink circulation temporarily stops after the initial state. Figure 6D This means that in Figure 6C The diagram illustrates the state immediately following the state after the second energy generating element 24 is driven to generate the ink circulation flow. (See diagram for example.) Figures 6A to 6D As shown, the U-shaped individual channels 23 have an inlet and outlet for the circulating ink flow arranged adjacent to each other. Note that the ink in the individual channels 23 is shaded with a dot pattern, and the density of the dot pattern shading is increased in the concentrated portions of the ink to indicate the degree of ink concentration.

[0105] like Figure 6A As shown, when the ink circulation is temporarily stopped, the volatile components of the ink evaporate from the injection orifice 11. Therefore, ink concentration progresses near the injection orifice 11. Then, by driving the second energy generating element 24, the ink circulation is restored. As a result, a system is established... Figure 6B The state shown. Figure 6A The entrance to the separate passage 23 and Figure 6A The outlets of the individual channels 23 are adjacent to each other. Therefore, ink concentrated near the jet orifice 11 is discharged from the outlet of the individual channel 23, but a portion of the discharged ink flows back into the individual channel 23 from the inlet. Thus, a phenomenon occurs where the ink in the individual channel 23 is not entirely replaced by fresh ink, but rather by slightly concentrated ink (hereinafter referred to as recirculation concentration). Then, in the case where the ink circulation temporarily stops, as... Figure 6C As shown, from Figure 6B The state begins, such as Figure 6A As before, ink concentration proceeds again near the injection orifice 11. Thereafter, the ink circulation is restored by driving the second energy generating element 24. As a result, as... Figure 6D As shown, due to the effect of recirculation and concentration, the ink in the entire individual channel 23 is drawn from... Figure 6B The ink is further concentrated through ink replacement. As described above, in the U-shaped individual channel 23, the ink concentration state is not reset each time the ink circulation flow is temporarily stopped and circulated, and ink concentration gradually progresses throughout the individual channel 23. Furthermore, it is assumed that the temporary stop and resumption of the ink circulation flow is not repeated. In this case, if the temporary stop period of the ink circulation flow is long and ink concentration progresses near the injection orifice 11, it is unlikely that an improvement in the ink concentration state will be achieved even when the ink circulation flow is resumed for the first time. This is because the improvement in the ink concentration state is small due to recirculation concentration.

[0106] Therefore, the straight-line single channel 23 and the U-shaped single channel 23 differ in their effect on discharging concentrated ink, leading to differences in the effectiveness of eliminating ink concentration through the temporary cessation and resumption of ink circulation. Specifically, in the case of the straight-line single channel 23, the ink concentration state, including the entire single channel 23, is more easily eliminated. Meanwhile, in the case of the U-shaped single channel 23, due to recirculation concentration, the ink concentration state, including the entire single channel 23, is not easily eliminated. Therefore, in the case of the U-shaped single channel 23, depending on the degree of concentration within the entire single channel 23, ink ejection may become unstable. Next, using... Figures 7A to 7C Explain the configuration of the portion of the U-shaped individual channel 23 near the injection orifice 11.

[0107] <Configuration of the portion of the U-shaped individual channel 23 near the ejection orifice 11>

[0108] Figures 7A to 7C is a diagram illustrating in detail the portion of the U-shaped individual channel near the ejection orifice 11. Figure 7A is a plan view observed along the direction in which liquid droplets are ejected from the ejection orifice 11. Figure 7B is Figure 7A is a VIIB-VIIB cross-sectional view. Figure 7C is Figure 7A is an enlarged schematic view of the individual channel 23 in the drawing.

[0109] in Figure 7A and Figure 7B each ejection orifice 11 is an opening portion formed in a part of the orifice plate 19. In the substrate 18, the first energy generating element 14 is formed at a position directly below corresponding to each ejection orifice 11. The 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 the direction indicated by the arrow 27 in the channel including the individual channel 23. In the substrate 18, a supply groove 42 is formed between the array of the first energy generating elements 14 and the array of the second energy generating elements 24 along the direction of the array of the ejection orifices 11 to penetrate through the substrate 18. The supply groove 42 communicates with the individual channel 23 and can supply ink to the individual channel 23. As described above, the configuration is not limited to the configuration provided with a plurality of independent supply openings (for example, Figures 3A to 3D the first supply opening 22 and the second supply opening 32) in the drawing, and a large opening such as the common supply groove 42 in Figures 7A to 7C the drawing can be used to allow liquid to flow in and out. Next, using Figures 8A to 8C the configuration of the portion of the linear individual channel 23 near the ejection orifice 11 will be explained.

[0110] <Configuration of the portion of the linear individual channel 23 near the ejection orifice 11>

[0111] Figures 8A to 8C is a diagram illustrating in detail the portion of the linear individual channel 23 near the ejection orifice 11. Figure 8A is a plan view observed along the direction in which liquid droplets are ejected from the ejection orifice 11. Figure 8B is Figure 8A is a VIIIB-VIIIB cross-sectional view. Figure 8C is Figure 8A is a VIIIB-VIIIB cross-sectional view, and is a cross-sectional view in which the internal configuration of the substrate 18 is different from the configuration in Figure 8B the drawing. Figure 8B and Figure 8CTwo examples are shown, which have different rear-side shapes of substrate 18 depending on the type of etching method applied to substrate 18, and the rear-side shape of substrate 18 can be any shape. In other words, the internal configuration of substrate 18 can be any configuration.

[0112] This configuration differs from the configuration of the portion of the U-shaped individual channel 23 near the injection orifice 11 in that the individual channel 23 has a straight configuration, wherein the inlet and outlet of the individual channel 23 are not adjacent to each other as in the U-shaped individual channel 23, but are separate from each other. Furthermore, the direction connecting the two ends of the straight individual channel 23 is perpendicular to the direction in which the injection orifices 11 are arranged to form an array, such as... Figure 8A As shown. This arrangement separates the location where the ink circulation flow enters the individual channel 23 from the location where the ink circulation flow exits the individual channel 23. Therefore, it can prevent the concentrated ink in the jet orifice 11 from flowing back into the individual channel 23. This suppresses the ink concentration effect. Next, using Figures 9A to 9C Another configuration of the section of the linear single channel 23 near the injection orifice 11 is explained.

[0113] <Another configuration of the section of the straight-line individual channel 23 near the injection orifice 11>

[0114] Figures 9A to 9C This is another schematic diagram explaining the portion of the linear single channel 23 near the injection orifice. Figure 9A It is a plan view taken along the direction in which droplets are ejected from the nozzle 11. Figure 9B yes Figure 9A IXB-IXB sectional view. Figure 9C yes Figure 9A The IXB-IXB cross-sectional view, and the configuration inside the substrate 18 therein. Figure 9B Different sectional views are configured within the same space. Figure 9B and Figure 9C Two examples are shown, each having a different rear-side shape of substrate 18 depending on the type of etching method applied to it, and the rear-side shape of substrate 18 can be any shape. Specifically, the internal configuration of substrate 18 can be any configuration. Furthermore, this configuration is related to... Figure 8A The difference in the configuration is that the number of ink supply opening arrays increases from two to three. This allows the number of jet orifice arrays 11 to be doubled, and the array of jet orifice 11 can be arranged on one side closer to the central ink supply opening. Specifically, the array of jet orifice 11 is arranged on both sides of the multiple ink supply openings in the array direction of the multiple ink supply openings at the center. This arrangement allows the number of ink supply opening arrays to be increased from two to three, and the number of jet orifice arrays 11 to be doubled from one to two. Furthermore, as... Figure 9A As shown, the two arrays of jet orifices 11 can be arranged such that they are offset from each other by the spacing between the two arrays of the corresponding jet orifices 11. Furthermore, wiring areas may not be included between the supply openings in the central ink supply opening array. Therefore, this configuration offers a high degree of freedom in terms of the size and resolution of the openings in the central ink supply opening array. This configuration enables rapid refilling of the jet orifices 11 and can handle high productivity. Note that the positions of the jet orifices 11 and the ink supply openings can be shifted according to the wiring routing. Next, the ink according to this embodiment will be explained.

[0115] <Ink>

[0116] As described above, although the degree of ink concentration elimination varies based on the configuration differences of the channels, including the individual channel 23, the following effects can be provided by generating a circulating flow of ink in the individual channel 23 using the second energy generating element 24. Specifically, the effects of concentrated ink that thickens due to the evaporation of volatile components in the ink at the injection orifice 11 can be suppressed. Therefore, the ink ejection state can be maintained at an excellent level, and the effects of ink ejection rate variations can be further reduced. Thus, ink ejection can be stabilized.

[0117] Furthermore, depending on the application of the liquid ejector head 1 or the liquid ejection device 50 equipped with the liquid ejector head 1, it is conceivable to use inks with different types of ink color materials, different contents of ink solids, etc. Specifically, the performance of the liquid ejector head 1 is preferably such that the liquid ejector head 1 can maintain ink ejection stability regardless of the type of ink used.

[0118] 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 in ordinary paper. In this case, it is advisable to use ink with reduced water content. Furthermore, in ink with low water content, the concentration of organic solvents other than water and the concentration of solid components (such as pigments and resins) in the ink are high. Therefore, the viscosity of the ink tends to increase rapidly as the water in the ink evaporates. Thus, ink with low water content tends to lead to a decrease in ink jetting stability. In view of this, when using ink with low water content, the increase in ink viscosity can be suppressed by generating a circulating flow of ink in a channel configuration including a separate channel 23 as in this embodiment. Typically, inks with a large amount of solid components have a solid content of 10 wt%. Specifically, this embodiment is preferably applied to inks containing a solid content of 10 wt% (also known as mass%) or more.

[0119] This section explains the relationship between the operating temperature of the liquid ejector head 1 and the viscosity of the ink. There is a scenario where a second energy-generating element 24, arranged throughout the liquid ejector chip 3, is driven and controlled to heat the liquid ejector head 1 until its temperature reaches a certain level, at which point the liquid ejector head 1 is used. The viscosity of the ink changes depending on its temperature. Therefore, the ink viscosity at the operating temperature of the liquid ejector head 1 affects the ink ejection stability.

[0120] 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 explained. When the ink circulation flow is generated by the second energy generating element 24, a circulation rate in which the instantaneous ink flow rate is tens of mm / s to 1,000 mm / s can be achieved. The average flow rate, as observed over a time width on the order of hundreds of μs, depends on the driving frequency of the second energy generating element 24. The reason is as follows: When the ink circulation flow is generated by the second energy generating element 24, the ink circulation flow is a transitional circulation flow that decays over time and stops after a certain period. Meanwhile, when the ink circulation flow 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 roughly the same level as 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 flow can be from a few mm / s to 100 mm / s. Next, the relationship between pigment concentration and the elimination of ink concentration is explained.

[0121] (Ink with high pigment concentration)

[0122] The case of inks with high pigment concentration is explained. For example, when using inks with a concentration such that the viscosity of the ink at the operating temperature of the liquid ejector head 1 is 3 cP or more and 6 cP or less, the ink tends to thicken near the ejector orifice 11 depending on the non-ejection period of the ink (also known as the pause period of the ink circulation flow). Therefore, the ink ejection rate tends to change. Consequently, the ink ejection stability tends to decrease. To suppress the decrease in ink ejection stability, it is preferable to generate a certain amount of ink circulation and circulate the ink while the pause period of the ink circulation flow is short. Therefore, it is preferable to perform a transitional ink circulation or a periodic ink circulation at a high frequency to eliminate ink concentration. The transitional ink circulation can be performed by driving the second energy generating element 24. Driving the second energy generating element 24 at a high frequency from the pause state of the ink circulation flow and restoring the ink circulation flow helps to eliminate ink concentration near the ejector orifice 11.

[0123] (Ink with low pigment concentration)

[0124] The case of inks with low pigment concentration is explained. For example, when using ink with a concentration such that the viscosity of the ink at the operating temperature of the liquid ejector head 1 is 1 cP or more and 2 cP or less, the ink may thicken near the ejector orifice 11 depending on the non-ejection period of the ink (also known as the pause period of the ink circulation flow). Therefore, a change in the ink ejection rate may occur, but less than the change in high-concentration ink. Meanwhile, when the pause period of the ink circulation flow is long, for example, depending on the non-printing drive period (also known as the stop period), the ink near the ejector orifice 11 may thicken. Therefore, when the liquid ejector head 1 is stopped and restarted after a certain period of non-printing, it is preferable to perform a recovery process involving waste ink, such as an ink suction operation, a wiping operation, or a combination of these operations, or a pre-ejection. Driving the second energy generating element 24 as a recovery operation to restore the ink circulation flow can help eliminate ink concentration near the ejector orifice 11 without generating waste ink. Furthermore, depending on the stop period, the generation of waste ink can be avoided by driving the second energy generating element 24 and performing a recovery process sufficient to restore the ink circulation flow. Alternatively, a recovery process can be performed, in which waste ink is minimized by combining a suction operation for removing air bubbles B from the liquid jet head 1, separate from the elimination of ink concentration, while restarting and restoring the ink circulation flow.

[0125] (A more suitable configuration for eliminating ink concentration)

[0126] As described above, in order to suppress the effect of concentrated ink, it is preferable to replace the concentrated ink with fresh initial ink whenever possible, for both high-concentration and low-concentration inks. Therefore, when driving the second energy generating element 24, the smaller the effect of circulating concentration, the higher the circulation effect is obtained. Specifically, compared with the configuration of the U-shaped single channel 23, the configuration of the linear single channel 23 can obtain a higher circulation effect. Next, by using... 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 will be explained.

[0127] <Heater Selection Circuit>

[0128] Figure 10This diagram illustrates an example of the circuit configuration of the printed element substrate 300 according to this embodiment. Various signals are supplied from the main PCB 400 to the printed element substrate 300. The main PCB 400 includes a power supply circuit 401 and a controller 402. The power supply circuit 401 applies a power supply voltage to the printed element substrate 300 via a power supply line VH. The power supply circuit 401 and the printed element substrate 300 are connected to each other via a ground line GNDH. The ground line GNDH is included in a ground wiring layer. The reference potential of the printed element substrate 300 is set by the ground wiring layer. Therefore, the ground line GNDH serves as the reference potential of the printed element substrate 300. The controller 402 is mainly formed by ROM, RAM, and CPU, and supplies various electrical signals to the printed element substrate 300. The controller 402 is connected to the printed 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. The enable signal is a signal that controls the period during which the controlled element is set to the on state and the current flows to that element based on the pulse width. The enable signal is a signal used to perform adjustments to achieve more ideal heat generation by taking into account manufacturing errors in the heater resistance value in the printed element substrate 300, manufacturing errors in the power supply circuit 401, and voltage drops in the power wiring when multiple heaters are driven simultaneously. In this embodiment, an example is given where the enable signal line HE is shared between jetting and cycling to reduce the number of signal terminals. However, providing separate enable signal lines HE for jetting and cycling allows for different pulse widths to be set for jetting and cycling. Note that when the enable signal line HE is shared between jetting and cycling as in this embodiment, the configuration is preferably as follows. Specifically, it is preferred that the jetting heater RhA and the cycling heater RhB are formed in the same step of the semiconductor manufacturing process, and the pulse width of the enable signal is adjusted to assume that the heaters have the same manufacturing error (the same resistance value deviation relative to the ideal value). 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.

[0129] The printing element substrate 300 includes jetting modules 301 and 302 and circulation modules 303 and 304. Jetting modules 301 and 302 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. In other words, the jetting heater RhA and the first energy generating element 14 refer to the same element. These terms are selectively used depending on whether the element is a circuit element or an element arranged in a separate channel 23. The jetting drive elements MD1 and MD2 are elements for causing current to flow in the jetting heater RhA. The jetting logic circuits AND1 and AND2 are elements for selectively driving the jetting drive elements MD1 and MD2. The printing element substrate 300 generates heat by causing current to flow in the jetting heater RhA. This causes ink to bubble and be ejected, allowing printing to be performed on the jetting target medium P.

[0130] Circulation modules 303 and 304 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. In other words, the circulation heater RhB and the second energy generating element 24 refer to the same element. These terms are used selectively depending on whether the element is a circuit element or an element arranged in a structure of individual channels 23. Circulation drive elements MD3 and MD4 are elements used to allow current to flow in the circulation heater RhB. Circulation logic circuits AND3 and AND4 are elements used to selectively drive the circulation drive elements MD3 and MD4. The printing element substrate 300 generates heat by allowing current to flow in the circulation heater RhB. This causes bubbles B in the ink to grow, and a circulating flow can be generated in the ink channels including individual channels 23.

[0131] Note that in the jet heater RhA, a piezoelectric element can be used as an element for jetting ink. In the circulating heater RhB, a piezoelectric element can be used as an element for circulating ink. Each of the jet driving elements MD1 and MD2 and the circulating driving elements MD3 and MD4 is an N-type high-voltage-tolerant transistor. Therefore, each of the jet driving elements MD1 and MD2 and the circulating driving elements MD3 and MD4 is a transistor with higher voltage tolerance than transistors used in logic circuits. The high-voltage-tolerant transistor is preferably configured such that it will not fail even when a voltage (e.g., 32V) is applied that is too high for the transistors in the general logic circuit forming the control unit to withstand.

[0132] The printing element substrate 300 includes a control data supply circuit 305. A group selection signal line 306, a time-division selection signal line 307, and an enable signal line HE are provided in the printing element substrate 300. 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 exchange various signals with 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.

[0133] 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 and the injection drive element MD1 are connected to each other. The output side of the injection logic circuit AND2 and the injection drive element MD2 are connected to each other. Therefore, the injection drive element MD1 is selected and controlled such that it enters a conduction state according to the output of the injection logic circuit AND1, and current flows in the injection heater RhA. Similarly, the injection drive element MD2 is selected and controlled such that it enters a conduction state according to the output of the injection logic circuit AND2, and current flows in the injection heater RhA. Furthermore, the cycle drive element MD3 is selected and controlled such that it enters a conduction state according to the output of the cycle logic circuit AND3, and current flows in the cycle heater RhB. Similarly, the cycle drive element MD4 is selected and controlled such that it enters a conduction state according to the output of the cycle logic circuit AND4, and current flows in the cycle heater RhB.

[0134] Although not shown, the control data supply circuit 305 includes a shift register and a latch circuit. In the shift register, the time-division selection signal is transmitted serially according to the clock signal. The latch circuit holds the time-division selection signal according to the latch signal.

[0135] (First scenario)

[0136] 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, the jet heater RhA and the circulation heater RhB are arranged as heaters on the printed element substrate 300. Furthermore, in... Figure 11In this process, jetting drive elements MD1 and MD2, and circulation drive elements MD3 and MD4 are arranged as drive elements on the printing element substrate 300. Furthermore, in Figure 11 In the figure, drain wirings 216, 217, 218, and 219 are arranged in the printed element substrate 300. Note that in the following explanation, 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 explanation, it is assumed that each of the cycle driving elements MD3 and MD4 is formed by a metal-oxide-semiconductor field-effect transistor (MOSFET). Note 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).

[0137] Specifically, in Figure 11 In this example, supply orifice arrays 205 and 206, jet heater array 201, circulation heater array 202, jet drive element array 203, and circulation drive element array 204 are arranged on the printing element substrate 300. In this embodiment, the circulation heater array 202 is arranged to the left of and alongside the supply orifice array 205. The jet heater array 201 is arranged to the left of and alongside the circulation heater array 202. The supply orifice array 206 is arranged to the left of and alongside the jet heater array 201. The jet drive element array 203 is arranged to the left of and alongside the supply orifice array 206. The circulation drive element array 204 is arranged to the left of and alongside the jet drive element array 203. A through-hole VIA is disposed between the jet heater array 201 and the supply orifice array 206. The through-hole VIA between the jet heater array 201 and the supply orifice array 206 is electrically connected to a power line VH in another wiring layer. A via VIA is disposed between the injection drive element array 203 and the circulation drive element array 204. The via VIA between the injection drive element array 203 and the circulation drive element array 204 is electrically connected to the ground wire GNDH in another wiring layer.

[0138] Multiple jet heaters RhA are arranged in an array in jet heater array 201. The arrangement density of jet heaters RhA is, for example, 600 dpi. Multiple circulating heaters RhB are arranged in an array in circulating heater array 202. Each circulating heater RhB is arranged close to a corresponding jet heater RhA to form a pair. Multiple units are arranged in jet drive element array 203, in which jet drive element MD1 and jet drive element MD2 are arranged adjacent to each other along the array direction. A shared ground electrode 209 is arranged in each unit as an electrode shared by jet drive element MD1 and jet drive element MD2 adjacent to jet drive element MD1. The shared ground electrode 209 is electrically connected to the ground wire GNDH in another wiring layer via via VIA. Multiple units are arranged in circulating drive element array 204, in which circulating drive element MD3 and circulating drive element MD4 are arranged adjacent to each other along the array direction. A shared ground electrode 210 is arranged in each unit as an electrode shared by circulating drive element MD3 and circulating drive element MD4 adjacent to circulating drive element MD3. Shared ground electrode 210 is electrically connected to ground wire GNDH in another wiring layer via via VIA, similar to shared ground electrode 209.

[0139] The distance P2 between the centers of gravity of the jet drive elements MD1 and MD2 in each unit is smaller than the distance P1 between the centers of gravity of the corresponding adjacent jet heaters RhA. The distance P2 between the centers of gravity of the jet drive elements MD1 and MD2 in each unit is smaller than the distance P1 between the centers of gravity of the corresponding adjacent circulating heaters RhB. For example, when the jet heaters RhA are arranged at 600 dpi, the distance P1 is 42.3 μm. Meanwhile, when a shared ground electrode 209 is included in each unit, the distance P2 is approximately 32 μm. Therefore, there is approximately 10 μm of extra space. By utilizing this extra space, substrate contacts 220 can be arranged between the jet drive elements MD1 and MD2 in the corresponding adjacent units. Similarly, by utilizing this extra space, substrate contacts 220 can also be arranged between the circulating drive elements MD3 and MD4 in the corresponding adjacent units. Furthermore, drain wirings 218 and 219 can be arranged using this extra space. In this example, the center of gravity is always meant relative to the center of the element region including the lead-out portions necessary for driving. In this embodiment, it is assumed that the current in the circulating heater RhB is less than the current in the jet heater RhA. Figure 11In the example, the cycle drive elements MD3 and MD4 are smaller in the array width direction than the jet drive elements MD1 and MD2, and have a smaller element area. In this example, it is assumed that the array width direction is a transverse direction within the same array that is orthogonal to the array (also called the vertical) direction.

[0140] Next, the arrangement of the injection drive elements MD1 and MD2, and the circulation drive elements MD3 and MD4, will be explained from a lateral perspective. Each of the injection drive elements MD1 and its corresponding counterpart in the circulation drive element MD3 are arranged adjacent to each other in the lateral direction to form a pair. Similarly, each of the injection drive elements MD2 and its corresponding counterpart in the circulation drive element MD4 are arranged adjacent to each other in the lateral direction to form a pair. When the injection drive elements MD1 and the circulation drive elements MD3 are grouped into a unit in the lateral direction, a shared ground electrode is shared in each unit. The shared ground electrode shared by the injection drive elements MD1 and the circulation drive elements MD3 in each unit is connected to the ground wire GNDH in another wiring layer via a via VIA. Sharing this shared ground electrode, as described above, reduces the area required to connect to the ground wire GNDH. Although the via VIAs are arranged in an array in this embodiment, the arrangement is not particularly limited to this. For example, the via VIAs can be arranged in multiple arrays depending on the density of the current flowing through them.

[0141] Furthermore, when each of the jet drive elements MD2 and its corresponding counterpart in the cyclic drive element MD4 are grouped into a single unit, a shared ground electrode is shared in each unit. The shared ground electrode shared by the jet drive elements MD2 and the cyclic drive elements MD4 in each unit is connected to the ground wire GNDH in another wiring layer via a via VIA. Sharing this shared ground electrode, as described above, reduces the area required to connect to the ground wire GNDH. In other words, the jet drive elements MD1 and MD2 and the cyclic drive elements MD3 and MD4 in the two segments can share an electrode electrically connected to the ground wire GNDH in a cross shape within the boundary area. Furthermore, the jet drive elements MD1 and MD2, which require a larger drive current than the cyclic drive elements MD3 and MD4, are arranged closer to the heating element region 280, which includes the jet heater RhA and the cyclic heater RhB, compared to the cyclic drive elements MD3 and MD4. This arrangement configuration can suppress the wiring resistance to the heating element region and achieve higher drive efficiency. Additionally, although a supply orifice array 206 is provided in this embodiment, it is not mandatory. Furthermore, although a separate supply aperture 208 is provided in the supply aperture array 205 in this embodiment, the supply apertures are not necessarily separate, and a configuration of a single long supply aperture extending along the array direction can be adopted. Note that the heating element region 280 is the region in the printing element substrate 300 where heating resistance elements are arranged in the same layer. In this embodiment, at least one of the jet heater RhA and the circulating heater RhB is used as a heating resistance element. Therefore, the heating element region 280 is the region in the printing element substrate 300 where at least one of the jet heater RhA and the circulating heater RhB is arranged. For example, the region in the printing element substrate 300 that includes the jet heater array 201 and the circulating heater array 202 in the same layer is the heating element region 280. Specifically, a plurality of jet heaters RhA formed as the jet heater array 201 are arranged in the first region of the heating element region 280. Furthermore, a plurality of circulating heaters RhB formed as the circulating heater array 202 are arranged in the second region of the heating element region 280. Note that if other heating resistor elements are arranged, these other heating resistor elements can be arranged in the third region of the heating element region 280.

[0142] (Second scenario)

[0143] Figure 12 This is a diagram illustrating an example arrangement of the heater and drive element according to a second case of this embodiment. Compared to the first case... Figure 11The difference lies in the reversed positional relationship between the jet heater array 201 and the circulating heater array 202. Specifically, the circulating heater array 202 is arranged relative to the jet heater array 201 on the drive element region 290 side, which includes jet drive elements MD1 and MD2 and circulating drive elements MD3 and MD4. Therefore, the arrangement of the jet drive element array 203 and the circulating drive element array 204 also differs from that in the first case. Specifically, the circulating drive element array 204 is arranged relative to the jet drive element array 203 on the side closer to the heating element region. This arrangement configuration allows for the arrangement of substrate contacts 220 between jet drive elements MD1 and MD2 in corresponding adjacent units by utilizing the extra space, as in the first case. Furthermore, by utilizing this extra space, substrate contacts 220 can be arranged between circulating drive elements MD3 and MD4 in corresponding adjacent units. Additionally, drain wirings 218 and 219 can be routed using this extra space. Specifically, the conductive layer and the wiring layer can be routed in the same layer in the drive element region 290. Note that the driving element region 290 is a region in the printing element substrate 300 where driving elements are arranged on the same layer. In this embodiment, at least one of jet driving elements MD1 and MD2 and cyclic driving elements MD3 and MD4 is used as a driving element. Therefore, the driving element region 290 is a region in the printing element substrate 300 where at least one of jet driving elements MD1 and MD2 and cyclic driving elements MD3 and MD4 is arranged. For example, the region in the printing element substrate 300 that includes the jet driving element array 203 and the cyclic driving element array 204 on the same layer is the driving element region 290. Specifically, the jet driving elements MD1 and MD2, which are formed as the jet driving element array 203, are arranged in the first region of the driving element region 290 on a unit basis. Furthermore, the cyclic driving elements MD3 and MD4, which are formed as the cyclic driving element array 204, are arranged in the second region of the driving element region 290 on a unit basis. Note that if other driving elements are arranged, these other driving elements may be arranged in the third region of the driving element region 290.

[0144] <First Comparison Example>

[0145] Figure 13 This is a diagram illustrating an example arrangement of the heater and drive element in the first comparative example. Figure 13An example is shown where a jet heater RhA is arranged without a circulating heater RhB. The jet heaters RhA are arranged at a density of 600 dpi and form a jet heater array 201. Jet drive elements MD21 are arranged at the same density as the jet heaters RhA, forming a jet drive element array 1204. The jet drive element array 1204 is arranged side-by-side with the jet heater array 201.

[0146] <Second Comparison Example>

[0147] Figure 14 This diagram illustrates 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, forming a jet heater array 201. The circulating heaters RhB are arranged at the same density as the jet heaters RhA, forming a circulating heater array 202. The jet heaters RhA are electrically connected to the jet drive element MD11 via wiring layer 1216. The circulating heaters RhB are electrically connected to the circulating drive element MD12 via wiring layer 1218. When forming the printed element substrate 300 using a low-cost manufacturing process, it is not preferable to provide an additional electrical connection wiring layer in a layer separate from the conductive layer used to lead out the electrodes of the jet drive element MD11 and the circulating drive element MD12. Specifically, the conductive layers in the jet drive element MD11 and the circulating drive element MD12, as well as wiring layers 1216 and 1218, are preferably formed in the same layer and in the same manufacturing step. Figure 14 In the example, multiple injection drive elements MD11 and multiple circulation drive elements MD12 are arranged as cells to form a drive element array 1203. In the drive element array 1203, the drive elements are arranged at 1200 dpi (twice the arrangement density of the injection heater RhA). In this arrangement configuration, wiring layer 1216 can be routed in the same layer as wiring layer 1218. However, in the second comparative example, the number of drive elements arranged along the array length direction is twice that in the first comparative example. Therefore, the size of each drive element along the array length direction is half that in the first comparative example. Figure 14 An example is shown in which the jet drive element MD11 is designed to have the same drive element area as in the first comparative example by doubling the size in the array width direction, in order to ensure sufficiently high drive performance so that the same drive current as in the first comparative example can flow in the jet drive element MD11.

[0148] Meanwhile, the drive current of the circulating heater RhB only needs to be large enough to generate the heat energy for circulating ink in the individual channel 23. Furthermore, when the drive current of the circulating heater RhB is less than the drive current of the jet heater RhA, the current drive performance of the circulating drive element MD12 can be lower than that of the jet drive element MD11. Therefore, the area of ​​the circulating drive element MD12 is preferably 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 to occupy the same area. Therefore, as a printing element substrate 300, an excessively large element size of the circulating drive element MD12 may lead to increased costs.

[0149] (Third scenario)

[0150] Figure 15 This is a diagram illustrating an example arrangement of the heater and drive element according to a third case of this embodiment. Figure 15 In this configuration, the jet heater RhA and the circulating heater RhB are arranged as heaters in the printed element substrate 300. Figure 15 In the printing element substrate 300, jetting drive elements MD1, MD2, MD5, and MD6, and circulating drive elements MD3, MD4, MD7, and MD8 are arranged as drive elements. In the first and second cases, each pair of adjacent jetting drive elements MD1 and MD2 forms a unit. Similarly, in the first and second cases, each pair of adjacent circulating drive elements MD3 and MD4 forms a unit. In the third case, depending on the arrangement spacing of the ink supply orifices 208 and the spacing of the drive elements, two or more drive elements form a unit.

[0151] Figure 15 An example is shown where four jet heaters RhA and four circulation heaters RhB are arranged for two ink supply orifices 208. Therefore, jet drive elements MD1, MD2, MD5, and MD6 are grouped into one unit. Furthermore, circulation drive elements MD3, MD4, MD7, and MD8 are grouped into one unit. Specifically, four drive elements are grouped into one unit. This configuration is such that the wiring from circulation drive elements MD4 and MD7 to the circulation heater RhB bypasses the outermost perimeter between the units. However, the electrodes in the boundary portions are shared by the four drive elements in the unit. Therefore, the increase in the drive element area can be suppressed. Next, using... Figures 16 to 19 Let's explain the details of the wiring configuration described above.

[0152] <Details of wiring configuration; Case 1>

[0153] Figure 16 This is a diagram showing an enlarged example of the driving element in the first case. Figure 16 In the diagram, injection drive elements MD1 and MD2, and cycle drive elements MD3 and MD4 are shown as drive elements. A gate electrode 221, a source electrode 212, and a drain electrode 216 are disposed in injection drive element MD1. A gate electrode 222, a source electrode 213, and a drain electrode 217 are disposed in injection drive element MD2. Source electrodes 212 and 213 are at the same potential. Furthermore, source electrodes 212 and 213 partially share electrodes in the shared ground electrode 209 via a shared ground electrode 211, and are connected to a ground line GNDH in another wiring layer via a via VIA.

[0154] Gate electrode 223, source electrode 214, and drain electrode 218 are disposed in loop drive element MD3. Gate electrode 224, source electrode 215, and drain electrode 219 are disposed in loop drive element MD4. Source electrode 214 and source electrode 215 are at the same potential. Furthermore, source electrode 214 and source electrode 215 partially share the electrodes in shared ground electrode 210 via shared ground electrode 211, and are connected to ground line GNDH in other wiring layers via via VIA. Additionally, shared ground electrode 210 is electrically connected to shared ground electrode 209 via wiring 225.

[0155] <Details of wiring configuration; second case>

[0156] Figure 17 This is a diagram showing an enlarged example of the driving elements in the second case. As described above, the positional relationship of the injection driving elements MD1 and MD2 and the circulation driving elements MD3 and MD4 in the left-right direction is reversed. Therefore, although the connection position via the via VIA to the ground wire GNDH is shifted to the right, the basic arrangement of the source electrode, drain electrode, and gate electrode of each driving element is the same as... Figure 16 The same as in [the text]. Therefore, its detailed explanation is omitted.

[0157] <Details of wiring configuration; Second comparison example>

[0158] Figure 18This is a diagram showing an enlarged example of the driving elements in the second comparative example. The jet driving element MD11 and the loop driving element MD12 are formed along the array length direction by repeating patterns of source electrodes 1212 and 1214 and drain electrodes 1216 and 1218. Therefore, there is not much flexibility to reduce the area of ​​the loop driving element MD12 solely by reducing its dimensions along the array length direction. However, there is flexibility to reduce the area of ​​the loop driving element MD12 by reducing its dimensions along the array width direction. Specifically, there is room to flexibly reduce the dimensions of the source electrode 1214, drain electrode 1218, and gate electrode 1223. However, the area formed by reducing the dimensions along the array width direction does not contribute to the miniaturization of the printed element substrate 300. Note that the wiring layer 1216 and the drain electrode 1216 are represented by the same symbol, and these elements are electrically connected to each other and at the same potential. These terms are used selectively depending on the focus, such as the traces of the wiring and the lead-out portions of the electrodes of the driving elements.

[0159] <Details of wiring configuration; cross-sectional view>

[0160] Figure 19 It shows along Figure 16 and Figure 17 A cross-sectional view of the XIX-XIX line. (See diagram.) Figure 19 As shown, in the semiconductor substrate 110, a P-well region 101 and N-well regions 102a and 102b are formed on the P-type silicon substrate 100. The impurity concentration of the N-well regions 102a and 102b relative to the P-type silicon substrate 100 is such that the breakdown voltage between the N-well regions 102a and 102b and the P-type silicon substrate 100 is higher than the voltage applied to the power line VH.

[0161] The impurity concentrations in P-well region 101 and N-well regions 102a and 102b are such that the breakdown voltage between 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 using the Localized Oxidation of Silicon (LOCOS) method.

[0162] (Configuration of injection drive elements MD1 and MD2)

[0163] The configuration of the injection drive elements MD1 and MD2 is explained. Figure 19An example of jet driving elements MD1 and MD2 formed by high-voltage-tolerant NMOS transistors is shown. Gate electrodes 221 and 222 are arranged via gate insulating film 104 on adjacent P-well regions 101 and N-well regions 102a and 102b. The overlapping region of P-well region 101 and gate electrodes 221 and 222 is the channel formation region.

[0164] The high-concentration N-type diffusion region 106 serves as the source electrode of the jet driving elements MD1 and MD2. The high-concentration P-type diffusion region 107 serves as 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 determines a reference potential. The N-well regions 102a and 102b include portions of field-reducing regions extending below the gate electrodes 221 and 222, which serve as drain electrodes. The high-concentration N-type diffusion region 106 formed in the N-well regions 102a and 102b serves as the drain electrode of the jet driving elements MD1 and MD2. Furthermore, the drain sides of gate electrodes 221 and 222 have a so-called LOCOS offset structure, in which the drain sides of gate electrodes 221 and 222 extend onto the field oxide film 103 formed in the N-well regions 102a and 102b. Therefore, even when the jet driving elements MD1 and MD2 are in the off state, that is, when the voltage of the drain electrode rises to the voltage applied to the power supply line VH while the voltage of the gate electrode is GND, the gate-drain breakdown voltage can be ensured.

[0165] 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 composed of an oxide film. Furthermore, the gate electrodes 221 and 222 can be, for example, polysilicon layers. The polysilicon layer, 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 for forming the jet driving elements MD1 and MD2, which form logic circuits at a low permissible level.

[0166] An insulating film with multiple contact portions 108 is disposed on a high-concentration P-type diffusion region 107, a high-concentration N-type diffusion region 106, and a field oxide film 103. Conductive layers 212, 213, 216, 217, and 220 are disposed on this insulating film. Each of the conductive layers 212, 213, 216, 217, and 220 can be formed of a metal such as aluminum. Note that the conductive layers, electrodes, and wiring only need to be electrically connected to each other, and their manufacturing methods, materials, and structures are not limited. Note that conductive layer 212 and source electrode 212 are represented by the same symbol, and these elements are electrically connected to each other and at the same potential. These terms are used selectively based on considerations such as the cross-sectional structure and the function of the leads from the electrodes of the driving element. The same applies to conductive layer 213 and source electrode 213. The same applies to drain wiring 216, conductive layer 216, and drain electrode 216. The same applies to drain wiring 217, conductive layer 217, and drain electrode 217. The same applies to drain wiring 218 and drain electrode 218. The same applies to drain wiring 219 and drain electrode 219. The same applies to conductive layer 220 and substrate contact 220. The same applies to conductive layer 221 and gate electrode 221.

[0167] In this example, the source electrodes of jet driving elements MD1 and MD2 share a P-well region 101, a high-concentration N-type diffusion region 106, a contact portion 108, and a conductive layer 221 via a shared ground electrode 209. When jet driving element MD1 is in the on-state, an on-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. Simultaneously, when jet driving element MD2 is in the on-state, an on-potential is applied to the gate electrode 222, and current flows from the conductive layer 216 on the drain electrode side to the shared ground electrode 209. In this embodiment, an example of the cross-sectional structure of jet driving elements MD1 and MD2 is explained. Cyclic driving elements MD3 and MD4 also have a similar cross-sectional structure and include a shared ground electrode 210. In the cross-sectional structure of cyclic driving elements MD3 and MD4, as shown... Figure 19 As shown, substrate contacts 220 are not arranged on both sides of the cross-sectional structure, and drain wirings 216 and 217 to the jet drive elements MD1 and MD2 are arranged on both sides.

[0168] Note that in this embodiment, an example is explained where the source electrodes of the injection drive elements MD1 and MD2 and the circulation drive elements MD3 and MD4 are at the same potential and share ground electrodes 209 and 210. However, this disclosure is not particularly limited to this example. For example, the configuration could be such that the drain electrode sides of the injection drive elements MD1 and MD2 and the circulation drive elements MD3 and MD4 are connected to the power line VH, and their source electrode sides are connected to the injection heater RhA and the circulation heater RhB, respectively. Next, by using... Figure 20 Another example of a circuit configuration for the printed element substrate 300 according to this embodiment will be explained.

[0169] <Another circuit configuration example>

[0170] Figure 20 This is a diagram illustrating another example of a circuit configuration for a printed element substrate according to this embodiment. Figure 20 It shows Figure 11 This is an example of a configuration where two arrays are arranged symmetrically with respect to the center point of the printing element substrate 300. The group selection signal line 306 and the time-division selection signal line 307 are arranged side-by-side with the jet drive element array 203. Although the control data supply circuit 305 is arranged close to the external connection terminal array 309, the control data supply circuit 305 can be arranged side-by-side with the group selection signal line 306 along the length of the array. The two jet heater arrays 201, arranged on the left and right sides with respect to the center of the printing element substrate 300, are arranged such that their coordinates in the length of the array are offset from each other by half a pitch relative to the heater spacing. However, the coordinates can be aligned with each other in the length of the array.

[0171] <Other Embodiments>

[0172] Although various examples and embodiments of this disclosure have been shown and explained above, the spirit and scope of this disclosure are not limited to the specific interpretations herein. This disclosure is not limited to the above embodiments, and various modifications can be made. Furthermore, portions of the above embodiments can be appropriately combined in this disclosure.

[0173] (Revised 1)

[0174] For example, although the example of using vias (VIAs) for electrical connection to other routing layers has been explained in this embodiment, this disclosure is not particularly limited to this example. For example, vias that enable electrical conduction between all routing layers can be used instead of vias (VIAs) that enable electrical conduction between one routing layer and another of multiple routing layers stacked on top of each other.

[0175] Other embodiments

[0176] Embodiments of this disclosure can also be implemented by a computer of a system or device that reads and executes computer-executable instructions (e.g., one or more programs) recorded on a storage medium (also more fully referred to as a "non-transitory computer-readable storage medium") to perform one or more functions in the above embodiments and / or includes one or more circuits (e.g., application-specific integrated circuits (ASICs)) for performing one or more functions in the above embodiments, and by a method executed by a computer of a system or device, for example by reading and executing computer-executable instructions from a storage medium to perform one or more functions in the above embodiments and / or controlling one or more circuits to perform one or more functions in 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 separate computers or networks of separate processors to read and execute computer-executable instructions. The computer-executable instructions may be provided to the computer, for example, from a network or 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, optical discs (such as laser discs (CDs), digital versatile discs (DVDs), or Blu-ray discs (BD)™), flash memory devices, memory cards, etc.

[0177] Other embodiments

[0178] 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.

[0179] According to this disclosure, driving elements can be appropriately arranged in a printed element substrate.

[0180] 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 following claims should be interpreted in the broadest possible sense to include all such modifications and equivalent structures and functions.

Claims

1. A printed component substrate, comprising: A heating resistor element group, wherein the heating resistor element group is arranged with multiple heating resistor elements; as well as A drive element group, wherein a plurality of drive elements configured to drive the plurality of heating resistor elements are arranged in a region on the same layer as the heating element region where the plurality of heating resistor elements are arranged, wherein... The drive element group includes: A first driving element array, the first driving element array comprising a plurality of first driving elements arranged in an array in a first region of a driving element region in which the plurality of driving elements are arranged; A second driving element array, comprising a plurality of second driving elements different from the plurality of first driving elements, wherein the plurality of second driving elements are arranged in an array alongside the first driving element array in a second region of the driving element region; and One or more inter-array wiring layers are arranged on the same layer between the first drive element array and the second drive element array, and the inter-array wiring layers are shared by the first drive element and the second drive element.

2. The printed element substrate according to claim 1, wherein... The first driving element array includes a plurality of first units, each of which is formed by grouping adjacent first driving elements among the plurality of first driving elements into units. The second driving element array includes a plurality of second units, each of which is formed by grouping adjacent second driving elements among the plurality of second driving elements into units, and The inter-array wiring layer is shared by the first unit and the second unit.

3. The printed element substrate of claim 2, wherein the inter-array wiring layer electrically connects the areas shared by the path of the drive current of the first drive element included in the first unit and the path of the drive current of the second drive element included in the second unit.

4. The printed element substrate according to claim 1, wherein... The heating resistor element group includes: A first heating resistor element array, wherein a plurality of first heating resistor elements are arranged in an array in a first region of the heating element region, and A second array of heating resistor elements, wherein multiple second heating resistor elements, different from the plurality of first heating resistor elements, are arranged in an array alongside the first heating resistor element array in a second region of the heating element region. The first heating resistor element array is arranged between the second heating resistor element array and the first driving element array, and The first driving element array is arranged between the first heating resistor element array and the second driving element array.

5. The printed element substrate according to claim 4, wherein... The first heating resistor element acts as a jet heater to generate energy for the liquid in the jet nozzle, and The second heating resistor element acts as a circulating heater to generate energy for circulating the liquid in the liquid jet head.

6. The printed element substrate according to claim 4, further comprising: A first wiring group, wherein each of the plurality of first heating resistance elements and a corresponding first driving element among the plurality of first driving elements are electrically connected to each other; as well as The second wiring group electrically connects each of the plurality of second heating resistor elements and a corresponding second driving element among the plurality of second driving elements to each other.

7. The printed element substrate according to claim 1, wherein... The drive element group also includes: The first array internal wiring layer, each of the first array internal wiring layers is shared by a corresponding group of adjacent first driving elements in the first driving element array, and The second array internal wiring layer, each of the second array internal wiring layers is shared by a corresponding group of adjacent second driving elements along the second driving element array, and The inter-array wiring layer, the first intra-array wiring layer, and the second intra-array wiring layer are electrically connected to each other.

8. The printed element substrate of claim 7, further comprising a ground wire configured to set a reference potential and electrically connected to each of the inter-array wiring layer, the first intra-array wiring layer, and the second intra-array wiring layer.

9. The printed element substrate of claim 8, wherein the ground wire is arranged in a layer different from the driving element region.

10. The printed element substrate according to claim 4, wherein the size relationship between the area of ​​the first driving element and the area of ​​the second driving element is the same as the size relationship between the driving current of the first heating resistor element and the driving current of the second heating resistor element.

11. The printing element substrate of claim 6, further comprising a plurality of supply orifices configured to supply ink, the plurality of supply orifices being configured at predetermined intervals between the first driving element array and the first heating resistor element array, wherein The first wiring group and the second wiring group are routed around the periphery of the supply orifice.

Images