Manufacturing method of liquid discharge head

Abstract

To precisely uniformize a thickness of a dry film used for a liquid discharge head.SOLUTION: A manufacturing method of a liquid discharge head includes: a first step in which a first resist is transferred to a substrate by relatively moving a transfer member in a first direction in a pressed state from an opposite side to a side facing the substrate with respect to the first resist so as to transfer the first resist to the substrate; and a second step in which a second resist is transferred to the first resist which has been transferred to the substrate by relatively moving the transfer member in a second direction different from the first direction in the pressed state from an opposite side to a side facing the first resist with respect to the second resist so as to transfer the second resist to the first resist.SELECTED DRAWING: Figure 7

Description

[Technical field]

[0001] The technique disclosed herein relates to a manufacturing method for a liquid ejection head that performs a recording operation by ejecting liquid. [Background technology]

[0002] Conventionally, a liquid ejection head is known in which a nozzle having a liquid ejection port for ejecting liquid and a flow path for supplying liquid to the ejection port is formed on a substrate having a liquid supply port for supplying liquid and an energy generating element for ejecting the liquid. In general, in order to realize high-quality printing, it is required to form the thickness of the nozzle of the liquid ejection head and the opening dimension of the ejection port with high accuracy. Patent Document 1 discloses a manufacturing method of a liquid ejection head in which a nozzle for ejecting liquid is formed on a substrate having a liquid supply port with a dry film resist. In this method, a first dry film is laminated on a substrate having a liquid supply port so as to cover the base step of the substrate to form a flow path forming member, and then a second dry film is laminated to form a discharge port forming member. Then, a discharge port and a flow path for ejecting liquid are formed by photolithography technology. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2020-49752 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, when laminating the dry film that will become the flow path forming member and the discharge port forming member, there is a considerable amount of variation in thickness due to the pressure distribution and temperature distribution specific to the device. In particular, when the same device is used multiple times, similar thickness variations are accumulated, and the thickness of the laminated dry film is difficult to be uniform within the substrate surface. Multiple chips to be mounted on the liquid discharge head are formed within the substrate surface, but if one chip is made longer to improve printing performance, the thickness of the nozzles arranged within the chip is difficult to be uniform, and the opening dimensions of the discharge port formed by photolithography technology are also difficult to be uniform. Therefore, there is a concern that it will be difficult to manufacture a high-quality liquid discharge head.

[0005] The technology disclosed herein has been made in view of the above, and has an object to make the thickness of a dry film used in a liquid ejection head uniform with high precision. [Means for solving the problem]

[0006] In order to achieve the above object, the manufacturing method of a liquid ejection head according to the present disclosure includes a manufacturing method of a liquid ejection head in which a resist is transferred to a substrate having a liquid supply port of the liquid ejection head to manufacture a liquid ejection head, the manufacturing method of a liquid ejection head including a first step of transferring a first resist to the substrate by moving the first resist relative to the substrate in a first direction while pressing a transfer member against the first resist from the side opposite to the substrate, in order to transfer the first resist to the substrate, and a second step of transferring a second resist onto the first resist transferred to the substrate by moving the second resist relative to the substrate in a second direction different from the first direction while pressing the transfer member against the second resist from the side opposite to the side opposite to the first resist. Effect of the Invention

[0007] According to the technique of the present disclosure, it is possible to reduce the variation in thickness of the dry film used in the liquid ejection head, and to manufacture a higher quality liquid ejection head. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a schematic perspective view illustrating an example of a liquid ejection head according to an embodiment. [Diagram 2] 2 is a schematic cross-sectional view of the liquid ejection head taken along line AA' in FIG. [Diagram 3] 5A to 5C are schematic diagrams illustrating an example of a process for manufacturing a liquid ejection head according to an embodiment. [Figure 4] FIG. 2 is a block diagram showing a partial configuration of a transfer device according to an embodiment. [Diagram 5] FIG. 2 is a schematic diagram illustrating a roller unit of a transfer device according to an embodiment. [Figure 6] FIG. 4 is a schematic diagram illustrating an example of transfer by a roller unit according to an embodiment. [Figure 7] FIG. 2 is a schematic top view illustrating an example of resist transfer according to an embodiment. [Figure 8] FIG. 11 is a schematic top view illustrating another example of resist transfer according to an embodiment. [Figure 9] FIG. 1 is a schematic top view showing an example of resist transfer according to a conventional technique. [Figure 10] FIG. 1 is a schematic cross-sectional view showing a resist in an example of transfer in the prior art. [Figure 11] FIG. 2 is a schematic cross-sectional view showing a resist in an example of transfer according to an embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Preferred embodiments of the technology of the present disclosure will be described in detail below with reference to the accompanying drawings. In each drawing, the same reference numerals are used for the same components, and duplicated descriptions will be omitted. Each embodiment will be described in more detail below. The numerical values ​​shown in each of the following examples are merely examples, and the technology of the present disclosure is not limited to these. The technology of the present disclosure is not limited to each of the examples, and includes combinations of these and applications to other technical fields.

[0010] (First embodiment) A method for manufacturing a liquid ejection head according to a first embodiment of the technique of the present disclosure will be described below. A liquid ejection head manufactured using a dry film as described below is mounted on, for example, an inkjet printer (not shown). There are various types of inkjet printers, but generally, the printer is provided with a carriage (not shown) that can move in a scanning direction, and the carriage has a liquid ejection head that ejects ink onto a printing medium. Ink is supplied to the liquid ejection head from an ink tank via a liquid flow path, and is ejected onto the printing medium from ejection ports provided in the liquid ejection head. Then, a desired print pattern is printed on the printing medium by repeating the scanning of the carriage and the ejection of ink from the liquid ejection head.

[0011] FIG. 1 is a perspective view showing a schematic example of a liquid ejection head according to the present embodiment. As shown in FIG. 1, a coordinate system consisting of an X-axis, a Y-axis, and a Z-axis, which are orthogonal to each other, is set for a liquid ejection head 100. The liquid ejection head 100 has a substrate 1 on which energy generating elements 2 are arranged at a predetermined pitch in the Y-axis direction. A liquid flow path 20 and a liquid ejection port 30 located above the energy generating elements 2 (positive direction of the Z-axis) are formed on the substrate 1. In addition, a liquid supply port 11 is formed on both sides of the energy generating elements 2 in the X-axis direction on the substrate 1. A plurality of nozzle rows each consisting of the liquid supply port 11, the liquid flow path 20, the liquid ejection port 30, and the energy generating elements 2 are arranged in the X-axis direction. When pressure is applied by the energy generated by the energy generating elements 2 to the liquid that flows in from the liquid supply port 11 and flows through the liquid flow path 20, the liquid is ejected as droplets from the liquid ejection port 30. The droplets adhere to a recording medium, thereby performing recording. The energy generated by the energy generating element 2 may be energy generated by a so-called thermal method or energy generated by a so-called piezoelectric method. In the following description, it is assumed that the energy generating element 2 is an energy generating element adopted for a thermal method.

[0012] Next, the liquid ejection head 100 will be described with reference to FIG. 2. FIG. 2 is a schematic cross-sectional view of the liquid ejection head 100 taken along line A-A' in FIG. 1. In the liquid ejection head 100, a plurality of energy generating elements 2 (not shown) are arranged on a substrate 1, and an insulating protective film (not shown) is formed thereon. The substrate 1 is also formed with a liquid supply port 11 for supplying liquid to a liquid flow path 20. A flow path wall defining the liquid flow path 20 is formed by a flow path forming member 21, and the liquid ejection port 30 is formed by an ejection port forming member 31. Here, the insulating protective film is patterned by photolithography, dry etching, or the like in accordance with the opening of the liquid supply port 11. The liquid supply port 11 communicates with the liquid flow path 20 and the liquid ejection port 30.

[0013] Next, a method for manufacturing the liquid ejection head 100 will be described with reference to FIGS. 3A to 3F. FIGS. 3A to 3F are schematic cross-sectional views of the liquid ejection head 100 taken along line A-A' in FIG. 1. As shown in FIG. 3A, a plurality of energy generating elements 2 (not shown) are arranged on a substrate 1, and an insulating protective film (not shown) is formed thereon. The material of the substrate 1 is not particularly limited as long as it is a material that can be used as a semiconductor element substrate, such as silicon. The material of the energy generating elements 2 is not particularly limited as long as it is a resistor, such as TaSiN, and the energy generating elements 2 can apply pressure to the liquid by heating the liquid upon receiving an electric signal. The material of the insulating protective film is an insulating film, such as SiN, SiC, or SiO, and is not particularly limited as long as it can protect the electrical wiring of the liquid ejection head 100 from ink and other liquids. The liquid supply port 11 is formed by penetrating the substrate 1 by dry etching or the like, and the processing method of the liquid supply port 11 is not particularly limited as long as the liquid supply port 11 can be formed to penetrate the substrate 1.

[0014] Next, as shown in FIG. 3B, in the first step, the flow path forming member 21 fixed to a base film (not shown) is transferred to the substrate 1. The flow path forming member 21 uses a dry film resist, and the material of the base film is not particularly limited as long as it is a material that is stable against the thermal history of the flow path forming member 21, such as polyethylene terephthalate or polyimide. In addition, the material of the flow path forming member 21 is preferably a negative type photosensitive resin. The film thickness of the flow path forming member 21 transferred to the substrate 1 is thinner than the film thickness of the flow path forming member 21 before being transferred to the substrate 1 because heating and pressure are applied during transfer.

[0015] Here, the transfer device 200 that transfers the flow path forming member 21 onto the substrate 1 will be described with reference to the drawings. Fig. 4 is a block diagram showing the configuration related to the roller unit among the configuration of the transfer device 200. As shown in the figure, the transfer device 200 has an electropneumatic regulator 201, a pressure cylinder 202, a pressure transmission plate 203, a roller unit 204, and a roller guide 205.

[0016] In the transfer device 200, air is pressure-controlled by an electropneumatic regulator 201 and transmitted to a pressure cylinder 202. The pressure cylinder 202 uses the air transmitted from the electropneumatic regulator 201 to press a pressure transmission plate 203. A roller unit 204, which is a transfer member, is connected to the pressure transmission plate 203. The roller unit 204 is engaged with a roller guide 205. The roller unit 204 scans along the extension direction of the roller guide 205 based on the control of a roller control unit (not shown).

[0017] 5 is a diagram showing a schematic diagram of the driving of the roller unit 204 of the transfer device 200. When the transfer device 200 transfers the dry film resist to the substrate 1, the roller unit 204 is first heated to a set temperature. Then, the pressure cylinder 202 presses the pressure transmission plate 203 by pressure control by the electropneumatic regulator 201, and the roller unit 204 descends. At this time, the roller unit 204 is guided by the roller guide 205. In a state where the dry film resist is engaged with the substrate 1, the roller unit 204 moves down together with the pressure transmission plate 203. Then, the roller unit 204 moves in the scanning direction while pressing the dry film resist against the substrate 1.

[0018] FIG. 6A is a top view of the stage 220, which shows a state in which the dry film resist is transferred to the substrate 1 by the roller unit 204. FIG. 6B is a cross-sectional view taken along the line A-A' in FIG. 6A. As shown in FIG. 6A, the substrate 1 is placed on the stage 220. The stage 220 has an outer peripheral stage 221 that surrounds the substrate 1 and an inner peripheral stage 222 on which the substrate 1 is placed. The outer peripheral stage 221 has a frame holding mechanism 510 as shown in FIG. 6B. In the present embodiment, as an example, the dry film resist is provided as a sheet-type dry film. Here, the sheet-type dry film is a dry film obtained by fixing a base film to a frame made of SUS (stainless steel), forming a resist on the base film, and then drying the resist to form a dry film.

[0019] In the transfer device 200, the shaft and rollers of the roller unit 204 are not perfectly horizontal, which causes variations in pressure inherent to the transfer device. It is not practical to perfectly level the shaft and rollers of the roller unit 204, but since rubber is used for the roller surface, even if the roller axial direction is not completely horizontal, the rubber deforms to conform to the surface of the substrate 1 fixed to the stage 220. In addition, since the substrate 1 has a round shape, when linear pressure is applied by the roller unit 204, the contact area between the roller and the substrate changes during scanning, and the actual pressure on the substrate 1 differs even if the pressure applied by the roller unit 204 is the same. Therefore, in order to suppress the variation in the contact area, the stage 220 is provided with an outer peripheral stage 221 outside the inner peripheral stage 222 that supports the substrate 1, thereby preventing the contact area of ​​the base to be pressed in the scanning area of ​​the roller from changing.

[0020] The roller unit 204 moves from the roller start point to the roller end point by sliding (pulse motor driven) one side of a rigid shaft formed in a lattice shape in the horizontal direction. When the roller unit 204 scans, the outer peripheral stage 221 receives the pressure of the roller unit 204 together with the substrate 1, thereby obtaining the effect of making the linear pressure applied by the roller unit 204 to the substrate 1 constant. In addition, as shown in Fig. 6B, the height of the inner peripheral stage 222 is set so that the surface of the substrate 1 and the surface of the outer peripheral stage 221 are on the same plane when the substrate 1 is placed on the inner peripheral stage 222.

[0021] As shown in FIG. 6B, the dry film resist 300 to be transferred to the substrate 1 is formed by laminating it on the base film 400 by spin coating or the like. The formed dry film resist 300 is held by the frame 500 together with the base film 400. Then, as shown in FIG. 6B, the frame 500 is held in a tilted state with respect to the stage 220 by the frame holding mechanism 510 provided on the outer peripheral stage 221. This prevents the dry film resist 300 from contacting the substrate 1 before the transfer by the roller unit 204. Then, the roller unit 204, which is a transfer member, is pressed against the dry film resist 300 from the side opposite to the side facing the substrate 1 to apply a pressing force. Then, the roller unit 204 is moved relative to the resist 300 from the roller start point to the roller end point, thereby expanding the area to which the pressing force of the dry film resist 300 is applied in the moving direction, and the dry film resist 300 is transferred to the substrate 1.

[0022] In this embodiment, in order to prevent the occurrence of gaps between the substrate 1 and the dry film resist 300, a method of transferring in sequence from one direction, such as a roller pressure method, is adopted. Although not shown, in order to prevent the occurrence of gaps between the substrate 1 and the dry film resist 300, the inside of the chamber may be depressurized before starting the transfer. Here, the heating temperature of roller unit 204 and the pressure applied by roller unit 204 during transfer can be appropriately set as long as dry film resist 300 can soften to cover steps on the surface of substrate 1 and the resin does not change in quality. The heating temperature of roller unit 204 and the pressure applied by roller unit 204 can be, for example, 60° C. or higher and 140° C. or lower, and 0.1 MPa or higher and 1.5 MPa or lower.

[0023] Here, the explanation will be continued by returning to Fig. 3C. As shown in Fig. 3C, the remaining portions of flow path forming member 21 are selectively exposed to light through a photomask, and then post-exposure heat treatment (hereinafter, PEB) is performed to optically determine cured portions 21A and uncured portions 21B. In this embodiment, it is assumed that a negative photosensitive resin is used as the resin of flow path forming member 21, so that the exposed portions become cured portions, with cured portions 21A corresponding to the flow path walls and uncured portions 21B corresponding to the liquid flow paths.

[0024] Next, as shown in FIG. 3D, in the second step, the discharge port forming member 31 fixed to the base film (not shown) is transferred onto the flow path forming member 21. The discharge port forming member 31 uses a dry film resist, and the supporting member is not particularly limited as long as it is a material such as polyethylene terephthalate or polyimide that is stable against the thermal history of the discharge port forming member. The material of the discharge port forming member 31 is preferably a negative photosensitive resin like the flow path forming member 21. The temperature and pressure of the roller unit 204 during transfer can be appropriately set so that the discharge port forming member 31 can be transferred and the flow path forming member 21 already formed on the substrate 1 is not deformed. The heating temperature of the roller unit 204 and the pressure by the roller unit 204 can be, for example, 30° C. or more and 50° C. or less, and 0.1 MPa or more and 0.5 MPa or less. Thereafter, the base film is peeled off from the discharge port forming member 31, and only the discharge port forming member 31 is left on the flow path forming member 21.

[0025] 3E, the remaining portions of the ejection port forming member 31 are selectively exposed to light through a photomask, and post-exposure PEB is performed to optically determine the cured portions 31A and the uncured portions 31B. In this embodiment, it is assumed that a negative photosensitive resin is used as the resin of the ejection port forming member 31, so that the exposed portions become the cured portions, the cured portions 31A correspond to the nozzles and flow channel ceiling that form the ejection ports, and the uncured portions 31B correspond to the liquid ejection ports 30.

[0026] Here, it is preferable that the discharge port forming member 31 is made of a material that is more sensitive to light during exposure than the flow path forming member 21. As a result, acid is generated in the discharge port forming member 31 by exposure, but acid is not generated in the uncured portion 21B of the flow path forming member 21. As a result, only the discharge port forming member 31 can be selectively patterned. Note that a liquid-repellent film may be formed on the upper surface of the discharge port forming member 31, and then exposure may be performed. Furthermore, when the liquid-repellent film is formed, the uncured portion of the flow path forming member 21 does not undergo a curing reaction.

[0027] Next, as shown in Fig. 3F, the uncured portions of the flow path forming member 21 and the discharge port forming member 31 are dissolved and removed using a solvent, and then development is performed. Here, it is preferable to develop the flow path forming member 21 and the discharge port forming member 31 at the same time. Note that performing development at the same time means developing all layers in a single process using one type of solvent.

[0028] Through the above steps, a substrate is completed having a liquid ejection head formed with a nozzle portion that ejects liquid flowing in from liquid supply port 11 from liquid ejection port 30. This substrate is then cut and separated into chips using a dicing saw or the like, and after bonding electrical wiring to drive the energy generating elements to each chip, a chip tank member for supplying liquid is bonded to the chip. This completes the liquid ejection head.

[0029] In this embodiment, as shown in FIGS. 7A and 7B, a transfer direction 21D (the direction of the arrow 21D in the figure) of the flow path forming member 21 and a transfer direction 31D (the direction of the arrow 31 in the figure) of the discharge port forming member 31 are different from each other. The direction of the transfer force is different from the direction of the transfer force (the direction of the transfer direction 31D) of the flow path forming member 21, which is the first resist. Therefore, when the dry film resist of the flow path forming member 21, which is the first resist, is transferred onto the substrate 1, the roller unit 204 is moved so as to expand the area where the pressing force is applied to the resist in the first direction (transfer direction 21D). Also, when the dry film resist of the discharge port forming member 31, which is the second resist, is transferred onto the dry film resist of the flow path forming member 21, the roller unit 204 is moved so as to expand the area where the pressing force is applied to the resist in the second direction (transfer direction 31D).

[0030] In this embodiment, as shown in FIG. 7A and FIG. 7B, the substrate 1 has a plurality of rectangular sections 5 corresponding to a plurality of chips manufactured from the substrate 1 on the surface to which the resist is transferred. Also, the nozzle row 51 of the liquid ejection head in one chip is arranged in the rectangular section 5. FIG. 7C is an enlarged view of one section 5 in FIG. 7A. Also, FIG. 7D is an enlarged view of one section 5 in FIG. 7B. As can be seen from FIG. 7C and FIG. 7D, the first direction (transfer direction 21D) and the second direction (transfer direction 31D) are directions sandwiching the mutually facing sides 6 and 7 of the rectangle constituting the section 5. This averages out the variation in thickness of the dry film due to transfer caused by the characteristics of each transfer device, and the thickness from the surface of the substrate 1 to the ejection port forming member 31 is easily formed uniformly on the substrate 1, and the opening dimensions of the liquid ejection port 30 are also easily formed uniformly.

[0031] In the example shown in the figure, the angle between the straight line 14 extending in the transfer direction 21D of the flow path forming member 21 and the straight line 15 extending in the transfer direction 31D of the discharge port forming member 31 in a plan view of the substrate 1 is 180°. That is, the first direction (transfer direction 21D) and the second direction (transfer direction 31D) in which the resist is transferred are directions along the rectangular sides of the section 5, respectively. However, the angle between the straight lines extending in these transfer directions is not limited to 180°. As shown in FIG. 7E, the angle between the straight line 14 extending in the transfer direction 21D and the straight line 15 extending in the transfer direction 31D is α. At this time, if the variation in the thickness of the dry film caused by the pressure distribution and temperature distribution in the transfer by the transfer device is small, these transfer directions are approximately opposite to each other, that is, the angle α between the directions may be in the range of ±5° (175° to 185°). Furthermore, in the dry film resist of the ejection port forming member 31, a plurality of liquid ejection ports are formed so as to form at least one row corresponding to the nozzle row 51. At this time, as shown in the figure, it is more preferable that the direction of the nozzle row 51 in the section 5 is parallel to one of the transfer directions, from the viewpoint of making the thickness of the dry film uniform in the extension direction of the nozzle row 51.

[0032] Furthermore, when changing the transfer direction 21D of the flow path forming member 21 and the transfer direction 31D of the discharge port forming member 31, the inner periphery stage 222 can be rotated to change the orientation of the wafer on which the substrate 1 is placed. This makes it possible to precisely uniform the thickness of the nozzle row 51 without impairing the in-plane stability of the transfer device.

[0033] In the above description, the moving direction of the roller unit 204 when transferring the dry film resist of the flow path forming member 21 is changed from the moving direction of the roller unit 204 when transferring the dry film resist of the discharge port forming member 31. However, when transferring at least one of the dry film resist of the flow path forming member 21 and the dry film resist of the discharge port forming member 31, the moving direction of the roller unit 204 may be changed and heating and pressurization may be repeated. That is, in the first step, after the roller unit 204 is moved in the transfer direction 21D, the roller unit 204 is moved in a third direction different from the transfer direction 21D. Here, the transfer direction 31D is an example of the third direction. Alternatively, in the second step, after the roller unit 204 is moved in the transfer direction 31D, the roller unit 204 is moved in a fourth direction different from the transfer direction 31D. Here, the transfer direction 21D is an example of the fourth direction. In this way, the moving direction of the roller unit 204 is changed in the transfer of one sheet of dry film resist. This is also expected to have the effect of making the thickness of the dry film uniform.

[0034] In the above description, the dry film resist is assumed to be a sheet-type dry film resist, but the above technology can also be applied to the case of transferring a roll-type dry film resist. In this case, the holding mechanism of the dry film resist on the stage 220 is changed.

[0035] Example 1 Next, a first example of the above embodiment will be described with reference to the drawings. In this example, the transfer direction 21D of the flow path forming member 21 and the transfer direction 31D of the discharge port forming member 31 are parallel to the extension direction of the nozzle row 51, and the angle α between the transfer directions is 180°. In other words, the first direction (transfer direction 21D) and the second direction (transfer direction 31D) are directions sandwiching the opposing sides of the rectangle that constitutes the section 5. This provides the effect of reducing the variation in thickness of the dry film caused by the pressure distribution and temperature distribution during transfer by the transfer device.

[0036] A method for manufacturing a liquid ejection head according to this embodiment will also be described with reference to Figures 3A to 3F. As shown in Figure 3A, a plurality of energy generating elements (not shown) are arranged on a substrate 1, and an insulating protective film (not shown) is formed thereon. A silicon substrate is used for the substrate 1, and TaSiN is used for the heating resistor. The insulating protective film is formed by depositing SiO and SiN by plasma CVD. Thereafter, a mask resist is formed on the insulating protective film, and after patterning, the substrate 1 is processed by dry etching to form a liquid supply port 11.

[0037] Next, as shown in FIG. 3B, a flow path forming member 21, which is a negative photosensitive resin, is formed on an insulating protective film (not shown) as a dry film on a support member. The flow path forming member 21 is formed so that the thickness on the energy generating element is 14 μm. A release-treated PET film is used as a support member for the dry film. The transfer temperature by the roller unit 204 is 70° C., and the transfer pressure is 0.5 MPa. The peeling speed of the support member is 5 mm / s. Here, as shown in FIG. 7A, the transfer direction 21D of the flow path forming member 21 is a direction intersecting one side 6 of the rectangular partition 5 that separates the product unit of the liquid ejection head in the dry film on the substrate 1, and is a direction parallel to the nozzle row 51 arranged in one product unit. At this time, as shown in FIG. 11A, a thickness difference G1 occurs as a whole in the flow path forming member 21 due to the variation in thickness of the dry film caused by the pressure distribution and temperature distribution specific to the transfer device.

[0038] Next, as shown in FIG. 3C, the portion of the flow passage forming member 21 that will become the flow passage side wall is exposed to i-line (wavelength 365 nm) through a photomask, and then PEB is performed. The exposure dose is 8000 J / m 2 The PEB is heated on a hot plate at 50°C for 4 minutes to promote the curing reaction.

[0039] Next, as shown in FIG. 3D, a discharge port forming member 31 made of a dry film-like negative photosensitive resin is formed on the flow path forming member 21 to a thickness of 10 μm. A release-treated PET film is used as a support member for the dry film. The transfer temperature by the roller unit 204 is 40° C., and the transfer pressure is 0.3 MPa. The peeling speed of the support member is 5 mm / s. Here, as shown in FIG. 7B, the transfer direction 31D of the discharge port forming member 31 is a direction intersecting with a side 7 different from one side 6 of a rectangular section 5 that divides the product unit of the liquid discharge head in the dry film on the substrate 1. The transfer direction 31D is also a direction parallel to the nozzle row 51 arranged in one product unit. Furthermore, the transfer direction 31D of the discharge port forming member 31 is a direction different from the transfer direction 21D of the flow path forming member 21 by 180°.

[0040] At this time, as shown in FIG. 11B, the transfer device may experience a dry flow caused by the pressure distribution and temperature distribution peculiar to the transfer device. The variation in film thickness is averaged out, and within a product unit, a relatively small thickness difference "G1-G2" (G1>G2) occurs.

[0041] Next, as shown in FIG. 3E, the portion of the discharge port forming member 31 that will become the flow passage ceiling is exposed to i-line (wavelength 365 nm) to optically determine the hardened portion 31A that will become the flow passage ceiling and the unhardened portion 31B that will become the discharge port. The exposure dose is 1000 J / m 2 Here, the uncured portion 21B of the flow path forming member 21 is also irradiated with light, but the exposure of the discharge port forming member 31 does not cause a curing reaction in the uncured portion 21B due to the adjustment of the material's light sensitivity. Then, after this exposure, PEB is performed. PEB is performed by heating on a hot plate at 90°C for 5 minutes to promote the curing reaction.

[0042] 3F, the uncured portions of the flow path forming member 21 and the discharge port forming member 31 are removed all at once by a development process to form the liquid flow path 20 and the liquid discharge port 30. Propylene glycol monomethyl acetate is used as a solvent for the uncured portions, and the development process is carried out for 15 minutes.

[0043] Through the above steps, a substrate for a liquid ejection head is completed, on which a nozzle portion is formed that ejects liquid flowing in from liquid supply port 11 through liquid flow path 20 from liquid ejection port 30. This substrate is cut and separated into chips using a dicing saw or the like, and after electrical wiring that drives the energy generating elements is joined to each chip, a chip tank member for liquid supply is joined. This completes a liquid ejection head in which the thickness from the surface of the substrate to the surface of the ejection port forming member is uniform within each product unit, and the opening dimensions of the liquid ejection ports are also uniform. When printing was performed with this liquid ejection head, it was confirmed that high-quality ejection characteristics were achieved.

[0044] Example 2 Next, Example 2 of the above embodiment will be described with reference to the drawings. In this example, the transfer direction of the flow path forming member is a direction intersecting one of two mutually connecting sides of the rectangular partitions that divide the product units in the dry film on the substrate, and the transfer direction of the discharge port forming member is a direction intersecting the other side of the two sides. Other points of this example are the same as those of Example 1, so detailed description will be omitted.

[0045] 8A and 8B, the transfer direction 21D (the direction of the arrow 21D in the figure) of the flow path forming member 21 and the transfer direction 31D (the direction of the arrow 31D in the figure) of the discharge port forming member 31 are different from each other. As shown in FIG. 8A, the transfer direction 21D of the flow path forming member 21 is a direction parallel to the extension direction of the nozzle row 51 arranged in the section 5 of the product unit in the dry film on the substrate 1. Also, as shown in FIG. 8B, the transfer direction 31D of the discharge port forming member 31 is a direction perpendicular to the extension direction of the nozzle row 51 in the dry film on the substrate 1.

[0046] FIG. 8C is an enlarged view of one of the sections 5 in FIG. 8A. FIG. 8D is an enlarged view of one of the sections 5 in FIG. 8B. As can be seen from FIG. 8C and FIG. 8D, when a first straight line 16 extending in a first direction (transfer direction 21D) intersects with the rectangle of the section 5, the first straight line 16 intersects with a side 6 of the rectangle of the section 5. When a second straight line 17 extending in a second direction (transfer direction 31D) intersects with the rectangle of the section 5, the second straight line 17 intersects with a side 8 different from the side 6 of the rectangle of the section 5. In the example of the figure, the first direction and the second direction are perpendicular to each other, but the angle between the first direction and the second direction is not limited to this.

[0047] For example, in the case where the liquid ejection port 30 of the liquid ejection head is disposed in a rectangular section 5 on the substrate 1, the above-mentioned transfer direction may be a direction intersecting with different sides of the rectangle constituting the section 5. In this case, for example, if the angle α between the transfer directions is 45° or more, it is expected that the variation in thickness of the dry film at the time of transfer will be reduced. That is, the difference between the line extending in the first direction (transfer direction 21D) and the line extending in the second direction (transfer direction 31D) will be 45° or more. The angle α (FIG. 7E) between the line is 45° or more and 315° or less.

[0048] According to this embodiment, as in the first embodiment, there is an advantage that the variation in thickness of the dry film caused by the pressure distribution and temperature distribution specific to the transfer device is averaged out. Also, as in the first embodiment, the thickness from the surface of the substrate to the surface of the ejection port forming member is formed uniformly within each product unit, and a liquid ejection head is completed in which the opening dimensions of the liquid ejection ports are also formed uniformly. As a result of printing with this liquid ejection head, it was confirmed that high-quality ejection characteristics were achieved.

[0049] (Comparative Example) Here, an example of a conventional method for manufacturing a liquid ejection head will be described as a comparative example to the above-mentioned Examples 1 and 2. In this comparative example, the transfer direction of the flow path forming member and the transfer direction of the ejection port forming member are directions that intersect with the same side of a rectangle that divides the product unit in the dry film on the substrate. Other points of this comparative example are the same as those of Example 1.

[0050] 9A, the transfer direction 921D of the flow path forming member in this comparative example is a direction parallel to the extension direction of the nozzle rows 51 arranged in the product unit in the dry film on the substrate 1, and is a direction intersecting with one side 6 of the rectangle that separates the product units. At this time, as shown in FIG 10A, a thickness difference G1 occurs in the flow path forming member due to the variation in thickness of the dry film caused by the pressure distribution and temperature distribution specific to the transfer device.

[0051] Next, as shown in Fig. 9B, the transfer direction 931D of the discharge port forming member is the same as the transfer direction 921D of the flow path forming member. As a result, as shown in Fig. 10B, the thickness variation of the dry film due to the pressure distribution and temperature distribution specific to the transfer device is added to the thickness difference that occurred when the flow path forming member was formed. As a result, within the product unit, a thickness difference "G1+G2" larger than the thickness difference in each of the above examples occurs.

[0052] Then, a liquid ejection head having a flow path and an ejection port is completed by the same process as in Examples 1 and 2. As a result of printing using this liquid ejection head, it was found that the amount of liquid ejected was somewhat unstable, and that the liquid ejection head had larger variations in the ejection port opening dimensions and the nozzle thickness from the substrate surface within each product unit than in Examples 1 and 2.

[0053] The disclosure of this embodiment includes the following method. (Method 1) A method for manufacturing a liquid ejection head by transferring a resist onto a substrate having a liquid supply port of the liquid ejection head, comprising the steps of: a first step of transferring the first resist to the substrate by relatively moving a transfer member in a first direction while pressing the transfer member against the first resist from an opposite side to a side facing the substrate; a second step of transferring the second resist onto the first resist transferred to the substrate by relatively moving the transfer member in a second direction different from the first direction while pressing the transfer member against the second resist from an opposite side to the side facing the first resist; A method for manufacturing a liquid ejection head, comprising: (Method 2) the substrate has a surface onto which the resist is transferred, the surface having a plurality of rectangular sections corresponding to a plurality of chips to be manufactured from the substrate; The first direction and the second direction are directions along the sides of the rectangle. 2. The method for producing a liquid ejection head according to claim 1, (Method 3) wherein the first direction and the second direction are opposite directions. 1. A method for manufacturing the liquid ejection head described in 1. (Method 4) The method for manufacturing a liquid ejection head according to Method 3, wherein the angle between the first direction and the second direction is within a range of ±5°. (Method 5) 2. The method for manufacturing a liquid ejection head according to claim 1, wherein the first direction and the second direction are perpendicular to each other. (Method 6) 2. The method for manufacturing a liquid ejection head according to claim 1, wherein an angle between the first direction and the second direction is equal to or greater than 45° and equal to or less than 315°. (Method 7) the first resist is a resist that forms a flow path for the liquid supply port, 7. The method for manufacturing a liquid ejection head according to any one of Methods 1 to 6, wherein the second resist is a resist that forms a liquid ejection port for the liquid supply port. (Method 8) In the second resist, the liquid ejection ports are formed in a plurality of rows so as to form at least one row; The method for manufacturing a liquid ejection head according to Method 7, wherein the first direction and the second direction are parallel to the at least one row. (Method 9) 9. The method for producing a liquid ejection head according to any one of methods 1 to 8, wherein the transfer member is heated in the first step and the second step. (Method 10) 10. The method for manufacturing a liquid ejection head described in any one of methods 1 to 9, characterized in that in the first step, after moving the transfer member in the first direction, the transfer member is moved in a third direction different from the first direction. (Method 11) A method for manufacturing a liquid ejection head described in any one of methods 1 to 10, characterized in that in the second step, after moving the transfer member in the second direction, the transfer member is moved in a fourth direction different from the second direction. [Explanation of symbols]

[0054] 1 substrate, 200 transfer device, 211 roller unit, 300 dry film resist

Claims

1. A method for manufacturing a liquid ejection head by transferring a resist onto a substrate having a liquid supply port of the liquid ejection head, comprising the steps of: a first step of transferring the first resist to the substrate by relatively moving a transfer member in a first direction while pressing the transfer member against the first resist from an opposite side to a side facing the substrate; a second step of transferring the second resist onto the first resist transferred to the substrate by relatively moving the transfer member in a second direction different from the first direction while pressing the transfer member against the second resist from an opposite side to the side facing the first resist; A method for manufacturing a liquid ejection head, comprising:

2. the substrate has a surface onto which the resist is transferred, the surface having a plurality of rectangular sections corresponding to a plurality of chips to be manufactured from the substrate; The first direction and the second direction are directions along the sides of the rectangle.

2. The method for manufacturing a liquid ejection head according to claim 1.

3. The method for manufacturing a liquid ejection head according to claim 1 , wherein the first direction and the second direction are opposite to each other.

4. 4. The method for manufacturing a liquid ejection head according to claim 3, wherein the angle between the first direction and the second direction is within a range of ±5 degrees.

5. 2. The method for manufacturing a liquid ejection head according to claim 1, wherein the first direction and the second direction are perpendicular to each other.

6. 2. The method for manufacturing a liquid ejection head according to claim 1, wherein an angle between the first direction and the second direction is equal to or greater than 45 degrees and equal to or less than 315 degrees.

7. the first resist is a resist that forms a flow path for the liquid supply port, 2. The method for manufacturing a liquid ejection head according to claim 1, wherein the second resist is a resist for forming a liquid ejection port for the liquid supply port.

8. In the second resist, the liquid ejection ports are formed in a plurality of rows so as to form at least one row; 8. The method for manufacturing a liquid ejection head according to claim 7, wherein the first direction and the second direction are parallel to the at least one row.

9. 2. The method for manufacturing a liquid ejection head according to claim 1, wherein the transfer member is heated in the first step and the second step.

10. 2. The method of manufacturing a liquid ejection head according to claim 1, wherein in the first step, after the transfer member is moved in the first direction, the transfer member is moved in a third direction different from the first direction.

11. 2. The method of manufacturing a liquid ejection head according to claim 1, wherein in the second step, after the transfer member is moved in the second direction, the transfer member is moved in a fourth direction different from the second direction.

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