Liquid jet recording element unit and method for manufacturing the same

Abstract

The present invention relates to a liquid ejection recording element unit including: a first substrate provided with a first partition wall that defines a first flow channel including an ejection port of a liquid, and an energy generation portion that generates energy for ejecting the liquid from the first flow channel; and a second substrate provided with a second partition wall that defines a second flow channel including a supply port of the liquid, the second substrate being stacked on the first substrate so that the second flow channel communicates with the first flow channel. The first partition wall and the second partition wall abut across a predetermined gap in a stacking direction of the first substrate and the second substrate. A hydraulic diameter of the gap is smaller than a hydraulic diameter of a smallest flow channel portion having a smallest flow channel cross-sectional area in the first flow channel. The present invention also relates to a manufacturing method of a liquid ejection recording element unit.

Description

Technical Field

[0001] This invention relates to a liquid jet recording element unit and a method for manufacturing the same. Background Technology

[0002] An inkjet printer is an output device that forms characters and images by ejecting small droplets of ink, which is a recording liquid, from an inkjet recording head. In recent years, inkjet printers have been used as home and office devices and have expanded into industrial applications. Such an inkjet recording head is formed by precisely bonding a recording element unit to a support member connected to an ink supply unit. The recording element unit is formed by electrical mounting of a recording element substrate (in which multiple jet energy generation portions, ink flow channels, and ink jet nozzles are formed in a silicon substrate), a jet signal output portion such as a driver IC, and a wiring board that transmits electrical signals from the printer body. In this regard, a method for forming ink flow channels in the recording element unit includes bonding multiple substrates. Japanese Patent Application Publication No. H06-218923 describes a technology that prevents loss of ink jet driving power due to adhesive overflow by providing recessed portions at the bonding surface during the process of forming ink flow channels via bonding. In addition, Japanese patent application publication number H07-266567 proposes a technique in which, in order to improve processability and yield, an adhesive is filled into a recessed portion formed on a bonding surface, and then the substrates are bonded together to form a flow channel. Summary of the Invention

[0003] Regarding inkjet recording heads, recent years have witnessed continuous progress in shrinking recording element substrates to further reduce product costs, as well as advancements in reducing component size to enhance performance. To meet these product requirements, the ink flow channels within the recording element unit need to be finer and narrower. On the other hand, when ink flow channels are formed by bonding multiple substrates with irregularities, the bonding area is smaller. Here, the ink flow channels themselves become narrower due to adhesive overflow, making them more prone to clogging. When this problem is addressed simply by employing the technology in Japanese patent applications with publication numbers H06-218923 and H07-266567, a problem arises because the formation of recessed portions that are not used as ink flow channels increases the chip surface area.

[0004] Therefore, the object of the present invention is to provide a technology that allows for the suppression of ink flow channel blockage caused by adhesive overflow without resulting in an increase in chip surface area.

[0005] To achieve the above objectives, the liquid jet recording element unit of the present invention includes:

[0006] A first substrate having a first partition wall and an energy generating portion, such that the first partition wall defines a first flow channel including a plurality of nozzles for ejecting liquid for image recording, and the energy generating portion generates energy for ejecting liquid from the first flow channel via the nozzles; and

[0007] A second substrate having a second partition wall defining a second flow channel including a supply port for supplying liquid, the second substrate being stacked and bonded to the first substrate via an adhesive such that the second flow channel communicates with the first flow channel.

[0008] The first partition wall and the second partition wall are adjacent to each other across a predetermined opposing distance in the stacking direction of the first substrate and the second substrate without the intervention of adhesive; and

[0009] The hydraulic diameter of the gap is smaller than the hydraulic diameter of the smallest flow channel portion having the smallest flow channel cross-sectional area in the first flow channel.

[0010] To achieve the above objectives, the method for manufacturing the liquid jet recording element unit of the present invention includes:

[0011] The liquid jet recording element unit includes:

[0012] A first substrate having a first partition wall and an energy generating portion, such that the first partition wall defines a first flow channel including a plurality of nozzles for ejecting liquid for image recording, and the energy generating portion generates energy for ejecting liquid from the first flow channel via the nozzles; and

[0013] A second substrate having a second partition wall defining a second flow channel including a supply port for supplying liquid, the second substrate being stacked and bonded to the first substrate via an adhesive such that the second flow channel communicates with the first flow channel; the method includes:

[0014] The substrate manufacturing steps for manufacturing the first substrate and the second substrate; and

[0015] The stacking steps involve stacking the first substrate and the second substrate by bonding them together with an adhesive.

[0016] In the stacking step, the first substrate and the second substrate are stacked such that no adhesive is applied to the gap between the first partition wall and the second partition wall adjacent to each other along the stacking direction of the first substrate and the second substrate, and the hydraulic diameter of the gap is smaller than the hydraulic diameter of the smallest flow channel portion having the smallest flow channel cross-sectional area in the first flow channel.

[0017] This invention allows for the suppression of ink flow channel blockage caused by adhesive overflow without resulting in an increase in chip surface area.

[0018] Further features of the invention will become apparent from the following description of exemplary embodiments, with reference to the accompanying drawings. Attached Figure Description

[0019] Figure 1A This is a schematic perspective view of the liquid jet recording element unit in an embodiment of the present invention;

[0020] Figure 1B This is a schematic perspective view showing the manufacturing process of a liquid jet recording element unit;

[0021] Figure 1C This is a schematic perspective view showing the manufacturing process of a liquid jet recording element unit;

[0022] Figure 1D This is a schematic perspective view showing the manufacturing process of a liquid jet recording element unit;

[0023] Figures 2A to 2C This is a schematic diagram showing the structure of the ink flow channel substrate;

[0024] Figures 3A to 3C This is a schematic diagram illustrating the ink flow channel structure in Embodiment 1 of the present invention;

[0025] Figures 4A to 4C This is a schematic diagram showing the structure of the ink flow channel component;

[0026] Figures 5A to 5C This is a schematic diagram of the ink flow channel structure, which consists of an ink flow channel substrate and ink flow channel components.

[0027] Figure 6 This is a schematic diagram illustrating the ink flow channel structure in Embodiment 2 of the present invention;

[0028] Figure 7 This is a schematic diagram illustrating the ink flow channel structure in Embodiment 3 of the present invention;

[0029] Figure 8A and Figure 8B This is a schematic diagram illustrating the ink flow channel structure in Embodiment 4 of the present invention; and

[0030] Figures 9A to 9C This is a diagram illustrating the hydraulic diameter of the ink flow channel in Embodiment 1 of the present invention. Detailed Implementation

[0031] The embodiments for carrying out the present invention will now be described in detail, with reference to the accompanying drawings and examples. The dimensions, materials, shapes, relative arrangements, etc., of the constituent parts described in the embodiments will be appropriately modified according to the construction of the device to which the present invention is applied and various conditions. Furthermore, not all combinations of features described in this embodiment are necessary as solutions to the problems of the present invention. The constituent elements described in the embodiments are merely illustrative, and the scope of the present invention is not intended to be limited to these constituent elements.

[0032] Next, refer to Figures 1A to 1D An overview of the construction of the liquid jet recording unit according to an embodiment of the present invention and a description of the manufacturing process (manufacturing method) of the liquid jet recording unit are also provided. Figure 1A This is a schematic diagram illustrating a liquid jet recording element unit according to an embodiment of the present invention. Figure 1B , Figure 1C and Figure 1D This is a schematic diagram illustrating the manufacturing process of a liquid jet recording element unit.

[0033] according to Figure 1A The liquid jet recording element unit 1 (hereinafter referred to as recording element unit 1) of the embodiment of the present invention shown is used in the liquid jet head of a liquid jet apparatus, which is provided in a liquid jet type recording apparatus, such as an inkjet printer. In an inkjet printer, the liquid jet head is configured as an inkjet recording head, which is used to record a desired image on a recording material by jetting ink, which is an image recording liquid, onto the recording material. In the recording apparatus, an ink cartridge is also provided as a liquid storage portion that contains the liquid supplied to the liquid jet head, and a conveying mechanism is provided as a recording material, such as a sheet, on which the recording is to be performed.

[0034] Ink supplied from an ink cartridge (not shown) passes through an opening 81, which serves as an ink supply port, through an ink flow channel defined within an ink flow channel member 80, an ink flow channel substrate 30, and a recording element substrate 10, and exits from an ink ejection port 14 (see, for example, see...). Figures 3A to 3C ) jetting. By receiving the jetting energy generated by the jetting energy generation section 17 (see, for example, see...) located in the ink flow channel. Figures 3A to 3C The energy generated causes ink to be ejected from ink ejector 14. The ink ejected from ink ejector 14 adheres to the image recording surface of the recording material, which is positioned to face ink ejector 14, thereby forming (recording) an image on the recording material.

[0035] Figure 1B This is a schematic perspective view illustrating the manufacturing process of the recording element unit 1, and shows a portion of the structure of the recording element unit 1 in an exploded manner. In the construction of the recording element unit 1, Figure 1B Specifically, the steps of integrating the recording element substrate 10, which serves as the first substrate (flow channel forming member), the ink flow channel substrate 30, which serves as the second substrate (flow channel forming member), the nozzle surface cover 40, and the electrical wiring member 50 are shown. Figure 1B Prior to the integration shown, corresponding flow channel structures are formed in the recording element substrate 10 and the ink flow channel substrate 30, for example, by etching the silicon substrate (substrate manufacturing step).

[0036] The recording element substrate 10, manufactured according to silicon etching technology, has an ink ejector 14 on the rear surface side (see, for example, [reference needed]). Figures 3A to 3C A wafer having an ejection energy generating section 17 and an electrode PAD 11 connected to the ejection energy generating section 17 formed thereon, and an ink ejection port 14 formed therein (see, for example, see...). Figures 3A to 3C The wafers of the interconnected ink flow channels 12 are joined together and then sliced ​​to obtain a monolithic recording element substrate 10.

[0037] First, an ink flow channel substrate 30 for forming an ink flow channel (through which ink is supplied to the recording element substrate 10) is stacked and bonded to the recording element substrate 10 (stacking step). In the ink flow channel substrate 30, flow channel openings are formed at the bonding surface (bonding surface) with the recording element substrate 10 and at the surface on the opposite side, thereby communicating with the ink flow channel 12 formed in the recording element substrate 10.

[0038] A driver IC 20 for generating and outputting electrical signals for ink ejection is electrically mounted on an electrical wiring component 50 connected to the printer body. In this embodiment, a flexible wiring board using polyimide in the base film and cover film is used as the electrical wiring component 50. The electrical wiring component is not limited to a specific component and can be suitably selected, for example, from printed wiring boards.

[0039] Next, the ink ejection nozzle 14 of the recording element substrate 10 is formed on the surface of the ejection nozzle (see, for example, see...). Figures 3A to 3C The nozzle surface cover 40 is joined to the nozzle opening in a manner that matches the ink ejection nozzle 14, and further joined to the electrical wiring component 50 on which the driver IC 20 is mounted. In this embodiment, aluminum oxide is used as the nozzle surface cover 40, but the material is not limited to this and can be appropriately modified to a metal component, etc.

[0040] Figure 1CIt is a schematic perspective view of the manufacturing process of the recording element unit 1, and shows a portion of the structure of the recording element unit 1 in an exploded manner. Figure 1C It shows in Figure 1B The step involves electrically connecting the recording element substrate 10 and the electrical wiring component 50, which are already integrated with each other. Specifically, the electrode PAD 11 disposed on the recording element substrate 10, which is engaged with the nozzle surface cover 40, and the electrode PAD 21 disposed on the driver IC 20 mounted on the electrical wiring component 50 are electrically connected to each other via wiring 22.

[0041] Figure 1D It is a schematic perspective view of the manufacturing process of the recording element unit 1, and shows a portion of the structure of the recording element unit 1 in an exploded manner. Figure 1D It shows protection and coverage Figure 1C The steps include forming the wiring 22 in the process, and further stacking and joining the ink flow channel component 80 as the third flow channel forming component.

[0042] Specifically, the electrically connected electrodes PADs 11 and 21 and wiring 22 are covered with sealing material 62. The electrical mounting devices and structures described herein are not limited to the above and can be modified as appropriate. For example, the nozzle surface cover 40 can be directly electrically connected to the recording element substrate 10 without engaging the electrical wiring components 50 and the driver IC 20.

[0043] Then, the ink flow channel component 80 is joined to the ink flow channel substrate 30. This forms... Figure 1A The recording element unit 1 is shown. In the ink flow channel member 80, flow channel openings are formed at the bonding surface (joining surface) that bonds to the ink flow channel substrate 30 and on the surface opposite thereto, thereby communicating with the first opening 31 formed in the ink flow channel substrate 30. In this embodiment, aluminum oxide is used as the ink flow channel member 80. The material is not limited to this and can be appropriately modified to a metallic material, etc.

[0044] Example 1

[0045] Next, we will refer to Figures 2A to 2C , Figures 3A to 3C , Figures 4A to 4C ,as well as Figures 5A to 5C The recording element unit 1 according to Embodiment 1 of the present invention is explained.

[0046] Figure 2A This is a schematic perspective view of the ink flow channel substrate 30 with its surface (the surface of the ink flow channel member 80) facing upwards, opposite to the bonding surface (the bonding surface) of the substrate 10 which bonds to the recording element substrate 10. Figure 2BThis is a schematic perspective view of the ink flow channel substrate 30 with its bonding surface (joint surface) that is bonded to the recording element substrate 10 facing upwards. Figure 2C This is a schematic plan view showing the planar structure of the ink flow channel substrate 30 in this embodiment, as viewed from one side of the bonding surface that is bonded to the recording element substrate 10. Figure 3A , Figure 3B and Figure 3C This is a schematic diagram showing the state in which an ink flow channel is formed by joining the recording element substrate 10 and the ink flow channel substrate 30 in this embodiment.

[0047] The flow channel (first flow channel) defined in the recording element substrate 10 including the ink ejector 14 and the flow channel (second flow channel) defined in the ink flow channel substrate 30 including the first opening 31 as the ink supply port are connected to each other due to substrate bonding, thereby forming the ink flow channel of this embodiment.

[0048] In the ink flow channel substrate 30, a second opening 32 is formed at a bonding surface (joint surface) 30b (second surface) that is joined with the recording element substrate 10, and a first opening 31 is formed at a surface 30a (first surface) opposite to the bonding surface 30b. The first opening 31 and the second opening 32 are connected to each other within the ink flow channel substrate 30.

[0049] Specifically, a plurality of first openings 31 are arranged on surface 30a in a spaced-apart manner along the longitudinal direction (first direction) and the transverse direction perpendicular to the longitudinal direction (second direction) of the ink flow channel substrate 30. This document employs a configuration in which the second openings 32 have a groove shape extending on the mating surface 30b along the longitudinal direction of the ink flow channel substrate 30, such that the plurality of first openings 31 open at the bottom of the groove in the same direction and are spaced-apart from each other. That is, the second openings 32 are configured to connect the plurality of first openings 31 arranged side-by-side in the longitudinal direction of the ink flow channel substrate 30. The second openings 32 are arranged side-by-side parallel to each other and spaced apart in the transverse direction of the ink flow channel substrate 30. Two given adjacent second openings 32 are separated by corresponding partition walls 37, which serve as second partition walls extending in the longitudinal direction. Therefore, the plurality of first openings 31 on the surface 30a opposite to the bonding surface 30b communicate with the ink flow channel 12 provided in the recording element substrate 10 via any one of the plurality of second openings 32 on one side of the bonding surface 30a that bonds with the recording element substrate 10. The ink flow channel substrate 30 has an annular bonding region 33 therein that bonds with the recording element substrate 10, thereby surrounding the plurality of second openings 32 on the outer periphery of the bonding surface 30b.

[0050] In itself, the recording element substrate 10 has an ink flow channel 12 with a groove shape extending in the longitudinal direction on a mating surface (bonding surface) that engages with the ink flow channel substrate 30, and a plurality of minimum flow channel portions 19 disposed at the bottom of the groove. The minimum flow channel portion 19 is a flow channel with the smallest flow channel cross-sectional area defined within the flow channels of the recording element substrate 10. The minimum flow channel portion 19 is connected to an energy-applying flow channel portion 14a, which serves as a flow channel space, opposite the jet energy generation portion 17 and the ink jet nozzle 14, for applying energy to the ink for ejection from the ink jet nozzle 13. The ink flow channels 12 are arranged parallel to each other and spaced apart in the transverse direction, corresponding to the second opening 32 of the ink flow channel substrate 30. Two given adjacent ink flow channels 12 are separated by a corresponding partition wall 15 (which serves as a first partition wall extending in the longitudinal direction). Two given ink flow channels 12 separated by a corresponding partition wall 15 are connected to each other via a corresponding energy-applying flow channel portion 14a.

[0051] Adhesive 60 is applied only to the outer periphery of the mating surfaces of the recording element substrate 10 and the ink flow channel substrate 30, thereby pressing the recording element substrate 10 and the ink flow channel substrate 30 together, thus compressing the adhesive 60 and bonding the recording element substrate 10 and the ink flow channel substrate 30. As a result, a communicating ink flow channel is formed from the first opening 31 of the ink flow channel substrate 30 to the ink ejection port 14 of the recording element substrate 10. Each pair of adjacent ink flow channels 12 and corresponding two second openings 32 in the lateral direction are separated from each other by corresponding partition walls 15 and 37 that are adjacent to each other in the substrate stacking direction.

[0052] In the energy-converting flow channel section 14a, ink flowing through such an ink flow channel is ejected from the ink ejection port 14 due to the energy generated by the ejection energy generating section 17. The specific construction of the ejection energy generating section 17 is not limited to a particular construction, but can, for example, provide a piezoelectric element, thereby changing the volume of the flow channel by deformation of the piezoelectric element, and generating pressure due to the ejection of ink. Furthermore, for example, an electrothermal exchange element can be provided, such that the ink is heated to generate bubbles, thus correspondingly causing the ink to be ejected.

[0053] The ink flow channel is a circulating ink flow channel, wherein ink is forced to flow from the first opening 31 of the ink flow channel substrate 30 toward the ejection energy generation section 17 of the recording element substrate 10 by an ink pressurization unit (not shown), so that un-ejected ink returns to the first opening 31. That is, two given ink flow channels 12 separated by a partition wall 15 are connected to each other via corresponding energy-generating flow channel sections 14a; similarly, two given second openings 32 separated by corresponding partition walls 37 adjacent to the partition wall 15 are also connected to each other. Therefore, as Figure 3B and Figure 3C As shown, ink can circulate and flow in two given ink flow channels separated by respective partition walls 15 and 37 that are adjacent to each other along the stacking direction of the recording element substrate 10 and the ink flow channel substrate 30 via energy-conducted flow channel portion 14a.

[0054] Figure 3B It is along Figure 3A The cross-sectional view of AA in the figure shows the path followed by the ink flowing from the first opening 31 of the ink flow channel substrate 30 toward the vicinity of the jet energy generation section 17 (arrow 70a). Figure 3C It is along Figure 3A The cross-sectional view of BB in the figure shows the path (arrow 70b) followed by unsprayed ink returning from near the jet energy generation section 17 to the first opening 31 of the ink flow channel substrate 30. Ink circulation in the liquid flow channel is not a necessary construction requirement of the present invention, and the present invention can also be employed similarly in ink flow channel constructions where circulation does not occur.

[0055] In this embodiment, the width 16 of the ink flow channel partition wall (i.e., the thickness of the partition wall 15) is in the range of 100 μm to 200 μm. When using adhesive to bond the partition wall 15 to the ink flow channel substrate 30 (partition wall 37), the ink flow channel may become clogged due to adhesive overflow. Therefore, in this embodiment, the area other than the opposing area between the partition wall 15 and the partition wall 37 (specifically, the outer peripheral area of ​​the bonding surface of the recording element substrate 10 and the ink flow channel substrate 30) is used as the bonding area where adhesive is applied in the bonding surface. As a result, clogging of the ink flow channel due to adhesive overflow can be suppressed without increasing the chip surface area. The recording element substrate 10 and the ink flow channel substrate 30, formed by silicon etching, are precisely finished in their respective bonding planes. As a result, by squeezing the adhesive applied only to the outer peripheral portion of the bonding surface as thinly as possible, the gap 61 (i.e., the opposing distance between each partition wall 15 and the ink flow channel substrate 30 (partition wall 37) in the stacking direction) can be minimized. The gap 61 between each partition wall 15 and the ink flow channel substrate 30 (partition wall 37) depends on physical properties such as the particle size of the filler contained in the adhesive 60 used, as well as viscoelasticity and curing shrinkage.

[0056] In this embodiment, the gap 61 between the partition wall 15 and the partition wall 37 is 0 to 25 μm, i.e. less than 25 μm, as a predetermined opposing distance.

[0057] Under the premise of using the same type of ink, the fluid resistance in the ink flow channel is usually defined by formula (1), which uses the hydraulic diameter dh according to the width of the flow channel and is based on the cross-sectional area A of the flow channel and the wet edge length (peripheral length of the cross-section) S of the relevant part.

[0058] dh=4A / S(1)

[0059] Within the scope of application of the present invention, as long as the hydraulic diameter dh1 of the minimum flow channel portion 19 and the hydraulic diameter dh2 of the gap 61 between the partition wall 15 and the partition wall 37 satisfy the relationship of formula (2).

[0060] dh1>dh2(2)

[0061] Figures 9A to 9C The hydraulic diameter dh1 of the minimum flow channel portion 19 and the hydraulic diameter dh2 of the gap 61 in the recording element unit 1 according to this embodiment are shown. Figures 9A to 9C As shown, in this embodiment, the minimum flow channel portion 19 is a 60μm × 60μm square with a width of 19w. Figure 3B and Figure 3CIn this embodiment, the distance of the gap 61 between the partition wall 15 and the partition wall 37 in the depth direction (the longitudinal direction of the ink flow channel substrate 30) is assumed to be 25 mm (=25000 μm). That is, in the gap between the bonding surfaces of the ink flow channel substrate 30 and the recording element substrate 10, the gap 61 between the partition wall 15 and the partition wall 37 is relatively long in the longitudinal direction to correspond to the second opening 32 and the ink flow channel 12, and is very narrow in the transverse direction. Therefore, the hydraulic diameter in this region is determined in this embodiment. In the calculation based on the above premise, the hydraulic diameter dh1 in the minimum flow channel portion 19 is 60, and the hydraulic diameter dh2 at the portion of the gap 61 between the partition wall 15 and the partition wall 37 is 50, thus satisfying the relationship of formula (2).

[0062] The smaller the hydraulic diameter of the gap 61 between partition wall 15 and partition wall 37 relative to the hydraulic diameter of the minimum flow channel portion 19, i.e., the smaller the hydraulic diameter, the greater the resistance to the fluid. Therefore, ink flows more easily in the minimum flow channel portion 19 than in the gap 61. In other words, by satisfying the relationship of formula (2), ink leakage from the gap 61 can be sufficiently suppressed even without the intervention of adhesive, so that neither the flow of ink to the vicinity of the jet energy generation portion 17 is hindered, nor is the circulation of ink within the flow channel hindered. Furthermore, since the same type of ink flows in the ink flow channel, no functional problems with the product will occur even under the assumption of a small amount of leakage from the gap 61 at the flow channel partition wall.

[0063] The values ​​for the width of the ink flow channel partition walls, the gap between the flow channel partition walls, and the minimum ink flow channel width are not limited to the values ​​mentioned above, and can be appropriately modified according to various design conditions such as the physical properties of the ink, the material of the ink flow channel components, and the internal pressure of the flow channel involved in the ink flow. The material of the ink flow channel substrate 30 is not limited to silicon, and polished metal or ceramic, for example, can be suitably used as the material of the ink flow channel substrate 30 herein, provided that the flatness of the mating plane that bonds to the recording element substrate 10 is satisfied relative to the allowable gap of the flow channel partition walls.

[0064] Figure 4A This is a schematic perspective view of the ink flow channel member 80 with its surface (first surface) facing upwards on the side opposite to the bonding surface that bonds with the ink flow channel substrate 30. Figure 4B This is a schematic perspective view of the ink flow channel member 80 with its mating surface (second surface) that is mated with the ink flow channel substrate 30 facing upwards. Figure 4C This is a schematic plan view showing the planar structure of the ink flow channel member 80 of this embodiment as viewed from the side of the bonding surface that is bonded to the ink flow channel substrate 30. Figure 5A , Figure 5B and Figure 5C This is a schematic diagram showing the state in which an ink flow channel is formed by joining the ink flow channel substrate 30 and the ink flow channel member 80 in this embodiment.

[0065] In the ink flow channel member 80, a second opening 82 is formed in the mating surface that engages with the ink flow channel substrate 30, and a first opening 81 is formed on the opposite side. Furthermore, the first opening 81 and the second opening 82 communicate within the ink flow channel member 80. The formation spacing of the first opening 81 and the second opening 82 is greater than the formation spacing of the openings 31 and 32 of the ink flow channel substrate 30, and thus serves to widen the ink flow channel spacing. The mating region 83 of the ink flow channel member 80 is defined here as the region between the second openings 82 (i.e., an elongated region along the transverse direction of the ink flow channel member 80 and arranged parallel and spaced apart from each other in the longitudinal direction) and the region surrounding the outer periphery of all the second openings 82. Adhesive is applied to the ink flow channel substrate 30 or the ink flow channel member 80 such that the adhesive overflows into the mating region 83 to bond the ink flow channel substrate 30 and the ink flow channel member 80 together.

[0066] and Figure 3B Similarly, here Figure 5B It is along Figure 5A The cross-sectional view of AA shows the path followed by the ink flow towards the vicinity of the jet energy generation section 17 (arrow 70a). Similar to... Figure 3C , here Figure 5C It is along Figure 5A The cross-sectional view of BB shows the path (arrow 70b) followed by unsprayed ink returning from near the jet energy generation section 17 to the first opening 81 of the ink flow channel member 80. The second opening 82 of the ink path shown in cross-sections AA and BB is separated by an adhesive (not shown). Although the recording element unit 1 in this embodiment has three ink flow channel forming members, the number of flow channel forming members is not limited to this, and it can be appropriately increased or decreased depending on, for example, the required flow channel spacing and the design configuration.

[0067] Therefore, this embodiment allows for the suppression of ink flow channel blockage caused by adhesive overflow without increasing the chip surface area. This improves the reliability of the recording performance of the recording device.

[0068] Example 2

[0069] Reference Figure 6The recording element unit according to Embodiment 2 of the present invention will be described. The basic structure and operation of the recording element unit of Embodiment 2 are the same as those of Embodiment 1. Therefore, elements in Embodiment 2 that have the same or corresponding functions and structures as those in Embodiment 1 will be indicated by the same reference numerals, and their detailed descriptions will be omitted. Features not specifically described in Embodiment 2 are the same as those in Embodiment 1.

[0070] Figure 6 This is a schematic cross-sectional view showing the state in which the ink flow channel is formed by joining the recording element substrate 10 and the ink flow channel substrate 30 of Embodiment 2. Compared to Embodiment 1, the filter 34 is now formed in the ink flow channel of the ink flow channel substrate 30. The function of the filter 34 is to block contaminants that have entered the corresponding ink flow channel, thereby suppressing clogging of the ink ejection nozzle and suppressing poor ink ejection.

[0071] For example, in the ink flow channel substrate 30 and the recording element substrate 10 formed by bonding multiple silicon wafers, a filter 34 can be formed by etching a via smaller than the ink flow channel in at least one of the bonded wafers at a portion corresponding to the ink flow channel. Besides silicon etching, other methods may be suitably employed, including, for example, using a photosensitive resin in the silicon wafers forming the ink flow channel substrate 30 and the recording element substrate 10 and forming vias smaller than the ink flow channel by photolithography.

[0072] Filter 34 is not limited to Figure 6 As shown, a filter 34 can also be formed in an ink flow channel component such as a recording element substrate 10 and an ink flow channel member 80.

[0073] Therefore, this embodiment achieves the same effect as Embodiment 1, and also allows for the prevention of contaminants from entering the ink flow channel, thus preventing compromised reliability.

[0074] Example 3

[0075] Reference Figure 7 The recording element unit according to Embodiment 3 of the present invention will be described. The basic structure and operation of the recording element unit of Embodiment 3 are the same as those of Embodiment 1. Therefore, elements in Embodiment 3 that have the same or corresponding functions and structures as those in Embodiment 1 will be indicated by the same reference numerals, and their detailed descriptions will be omitted. Features not specifically described in Embodiment 3 are the same as those in Embodiment 1.

[0076] Figure 7This is a schematic cross-sectional view showing the state in which the ink flow channel is formed by joining the recording element substrate 10 and the ink flow channel substrate 30 of Embodiment 3. Compared to Embodiment 1, the damping film 35 is now formed in the ink flow channel of the ink flow channel substrate 30. Through the action of the damping film 35, the jetting driving force applied to the ink from the jetting energy generation section 17 propagates within the flow channel, thereby suppressing adverse effects on ink jetting.

[0077] The damping film 35 can be formed, for example, by forming a polyimide film in an opening, which is formed by etching through holes in the recording element substrate 10 and the ink flow channel substrate 30, which are formed by bonding multiple silicon wafers. The damping film 35 is not limited to a polyimide film, and a similar structure can be achieved by forming an elastic film in the ink flow channel substrate 30 and the recording element substrate 10.

[0078] Damping membrane 35 is not limited to Figure 7 The form shown, for example, damping film 35, can also be formed in ink flow channel components such as recording element substrate 10 and ink flow channel member 80.

[0079] Therefore, this embodiment achieves the same effect as Embodiment 1, and also allows for control of the flow characteristics within the ink flow channel according to the physical properties of the ink used.

[0080] Example 4

[0081] The following will refer to Figure 8A and Figure 8B Embodiment 4 of the present invention will be described. The basic structure and operation of the recording element unit in Embodiment 4 are the same as those in Embodiment 1. Therefore, elements in Embodiment 4 that have the same or corresponding functions and structures as those in Embodiment 1 will be indicated by the same reference numerals, and their detailed descriptions will be omitted. Features not specifically described in Embodiment 4 are the same as those in Embodiment 1.

[0082] Figure 8A This is a schematic plan view showing the ink flow channel substrate 30 of Embodiment 4 of the present invention. Figure 8BThis is a schematic cross-sectional view showing the state in which an ink flow channel is formed by joining the recording element substrate 10 and the ink flow channel substrate 30 in Embodiment 4. Compared to Embodiment 1, in Embodiment 4, partition walls between the colors of the ink flow channels are provided in the recording element substrate 10 and the ink flow channel substrate 30. Specifically, the types (colors, etc.) of ink supplied from the plurality of first openings 31 are set to be different from each other, and the division of the ink flow channels (liquid flow channels) formed between the recording element substrate 10 and the ink flow channel substrate 30 is such that multiple ink flow channels are formed independently for each type of ink. For example, partition wall 15b, as a third partition wall, is provided in the recording element substrate 10, while partition wall 18, as a fourth partition wall, is provided in the ink flow channel substrate 30 so as to be adjacent to partition wall 15a in the stacking direction. Adhesive 60 is placed between partition wall 15b and partition wall 18, thereby bonding the above components together. In this configuration, the liquid flow channels can be divided for various types of ink, so that once the technology of the present invention is deployed in a recording device with a multi-color head, an implementation that suppresses the mixing of multiple types of ink can be achieved. Considering the overflow of the adhesive 60, the width (thickness) of the partition walls 15b and 18 in this embodiment is set to a value of 300 μm or more. This value can be appropriately modified by providing the area through which the overflowing adhesive escapes.

[0083] Therefore, this embodiment achieves the same effects as embodiments 1 to 3, and also allows for the formation of highly reliable ink flow channels corresponding to various types of ink. Thus, this embodiment allows for improved inkjet reliability, and consequently, also improves the reliability of the recording performance of the recording device. This embodiment is not limited to... Figure 8A and Figure 8B The form shown is illustrated, and similar constructions can be applied to various flow channel shapes.

[0084] The structures shown in the above embodiments can be combined with each other, as long as doing so does not create a technical contradiction.

[0085] Although the invention has been described with reference to exemplary embodiments, it should be understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the appended claims should be given the broadest interpretation to cover all such variations and equivalent structures and functions.

Claims

1. A liquid jet recording element unit, comprising: A first substrate having a first partition wall and an energy generating portion, such that the first partition wall defines a first flow channel including a plurality of nozzles for ejecting liquid for image recording, and the energy generating portion generating energy for ejecting liquid from the first flow channel via the nozzles. as well as A second substrate having a second partition wall defining a second flow channel including a supply port for supplying liquid, the second substrate being stacked and bonded to the first substrate via an adhesive such that the second flow channel communicates with the first flow channel. The first partition wall and the second partition wall are adjacent to each other across a predetermined opposing distance in the stacking direction of the first substrate and the second substrate without the intervention of adhesive; and The hydraulic diameter of the gap is smaller than the hydraulic diameter of the smallest flow channel portion having the smallest flow channel cross-sectional area in the first flow channel.

2. The liquid jet recording element unit according to claim 1, The first substrate and the second substrate are silicon substrates.

3. The liquid jet recording element unit according to claim 1 or 2, The thickness of the portion of the first partition wall that forms the gap is 100 μm to 200 μm.

4. The liquid jet recording element unit according to claim 1 or 2, The predetermined opposing distance is less than 25 μm.

5. The liquid jet recording element unit according to claim 1 or 2, The first substrate and the second substrate are joined by an adhesive applied only to the outer peripheral portion of the bonding surface.

6. The liquid jet recording element unit according to claim 1 or 2, The liquid flow channel is configured to connect from the supply port to the plurality of injection ports via the second flow channel and the first flow channel; and the liquid flow channel is configured to allow liquid not ejected from the plurality of injection ports to circulate through the interior of the liquid flow channel.

7. The liquid jet recording element unit according to claim 6, The liquid jet recording element unit further includes a filter disposed in the liquid flow channel.

8. The liquid jet recording element unit according to claim 6, The liquid jet recording element unit further includes a damping membrane disposed in the liquid flow channel.

9. The liquid jet recording element unit according to claim 1 or 2, The second substrate includes multiple supply ports; and The liquid supplied from each of the plurality of supply ports is of the same type.

10. The liquid jet recording element unit according to claim 1 or 2, The second substrate includes multiple supply ports. The liquid flow channel is configured to connect from a plurality of supply ports to the plurality of injection ports via the second flow channel and the first flow channel; and the liquid flow channel is divided into a plurality of liquid flow channels corresponding to the type of liquid supplied from each of the plurality of supply ports; The first substrate has a third partition wall that divides the first flow channel into a plurality of first flow channels and divides the plurality of injection ports into corresponding plurality of first flow channels. The second substrate has a fourth partition wall that divides the second flow channel into a plurality of second flow channels, which correspond to the plurality of first flow channels. and The third and fourth partition walls are adjacent to each other by being joined together via an adhesive in the stacking direction.

11. The liquid jet recording element unit according to claim 10, The thickness of the portion of the third partition wall and the fourth partition wall that are joined together by adhesive in a direction perpendicular to the stacking direction and in which the plurality of first flow channels are arranged side by side is greater than the thickness of the portion of the first partition wall that forms the gap in the same direction perpendicular to the stacking direction and in which the plurality of first flow channels are arranged side by side.

12. The liquid jet recording element unit according to claim 10, The thickness of the portion of the third and fourth partition walls that are joined together by means of an adhesive is 300 μm or more.

13. The liquid jet recording element unit according to claim 11, The thickness of the portion of the third and fourth partition walls that are joined together by means of an adhesive is 300 μm or more.

14. A method for manufacturing a liquid jet recording element unit, The liquid jet recording element unit includes: A first substrate having a first partition wall and an energy generating portion, such that the first partition wall defines a first flow channel including a plurality of nozzles for ejecting liquid for image recording, and the energy generating portion generating energy for ejecting liquid from the first flow channel via the nozzles. as well as A second substrate having a second partition wall defining a second flow channel including a supply port for supplying liquid, the second substrate being stacked and bonded to the first substrate via an adhesive, such that the second flow channel communicates with the first flow channel; the method includes: The substrate manufacturing steps for manufacturing the first substrate and the second substrate; and The stacking steps involve stacking the first substrate and the second substrate by bonding them together with an adhesive. In the stacking step, the first substrate and the second substrate are stacked such that no adhesive is applied to the gap between the first partition wall and the second partition wall adjacent to each other along the stacking direction of the first substrate and the second substrate, and the hydraulic diameter of the gap is smaller than the hydraulic diameter of the smallest flow channel portion having the smallest flow channel cross-sectional area in the first flow channel.

15. The method for manufacturing the liquid jet recording element unit according to claim 14, In the substrate manufacturing step, the first substrate and the second substrate are manufactured by silicon etching.

16. The method of manufacturing the liquid jet recording element unit according to claim 14 or 15, in, In the substrate manufacturing step, the first substrate is manufactured such that the thickness of the portion of the first partition wall that forms the gap is in the range of 100 μm to 200 μm.

17. The method of manufacturing the liquid jet recording element unit according to claim 14 or 15, In the stacking step, the first substrate and the second substrate are stacked such that the opposing distance between the first partition wall and the second partition wall spanning the gap is less than 25 μm.

18. The method of manufacturing the liquid jet recording element unit according to claim 14 or 15, In the stacking step, the first substrate is bonded to the second substrate by applying adhesive only to the outer peripheral portion of the bonding surfaces of the first substrate and the second substrate.

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