JP2021187010A - Method and apparatus for manufacturing liquid discharge head - Google Patents

Abstract

To suppress a step of mutually adjacent element substrates even when thermal deformation of a support member is large.SOLUTION: There is provided a method for manufacturing a liquid discharge head 6 in which a first element substrate 3A and a second element substrate 3B are mounted on a mounting surface 7 of a support member 1, and a discharge port formation surface 8 of the second element substrate 3B and the mounting position of the second element substrate 3B in the mounting surface 7 are separated from each other by a second distance d2 in a direction Z perpendicular to the mounting surface 7. The manufacturing method includes the steps of: heating and curing a first thermosetting adhesive 4A formed on the mounting surface 7, and joining the first element substrate 3A to the mounting surface 7 through the first thermosetting adhesive 4A; and positioning the second element substrate 3B so as to maintain the second distance d2 in a state where the support member 1 is thermally deformed by heating the first thermosetting adhesive 4A, heating and curing the second thermosetting adhesive 4B formed on the mounting surface 7, and joining the second element substrate 3B to the mounting surface 7 through the second thermosetting adhesive 4B.SELECTED DRAWING: Figure 5

Description

The present invention relates to a method and an apparatus for manufacturing a liquid discharge head.

In a liquid ejection device such as an inkjet recording apparatus, a liquid ejection head in which a plurality of element substrates provided with ejection ports for ejecting liquid such as ink are arranged on a support member may be used. If a step is formed at the connecting portion of the adjacent element substrates, the position where the ejected droplets land on the recording medium is displaced, and color unevenness or streaks may occur. Therefore, when joining a plurality of element substrates to the support member, it is preferable to make the heights of the discharge port forming surfaces as uniform as possible. Patent Document 1 discloses a technique in which a bonding material applied to a substrate is crushed by an element in order to make the heights of the plurality of elements uniform, and the distance between the substrate and the plurality of elements is made uniform.

Japanese Unexamined Patent Publication No. 2011-033763

In the liquid discharge head, when a plurality of element substrates are joined to a support member with a thermosetting adhesive, it is possible to suppress a step difference between element substrates adjacent to each other by using a technique as disclosed in Patent Document 1. Is. In recent years, a resin support member may be used in order to reduce the cost of the liquid discharge head. Since the resin support member has a large coefficient of linear thermal expansion, it is significantly thermally deformed when the thermosetting adhesive is heated. Therefore, even if the heights are made uniform at the time of joining the element substrates, the height of the element substrates may change when the support member returns to room temperature and the thermal deformation disappears.

An object of the present invention is to provide a method for manufacturing a liquid discharge head, which can suppress a step difference between element substrates adjacent to each other even when the support member has a large thermal deformation.

In the present invention, the first element substrate and the second element substrate are mounted on the mounting surface of the support member, and the ejection port forming surface of the second element substrate and the mounting position of the second element substrate on the mounting surface are set. The present invention relates to a method for manufacturing a liquid discharge head separated by a second distance in a direction orthogonal to the mounting surface. In this manufacturing method, the first thermosetting adhesive formed on the mounting surface is heat-cured, and the first element substrate is bonded to the mounting surface via the first thermosetting adhesive. The second element substrate is positioned so as to maintain the second distance in a state where the support member is thermally deformed by the heating of the first thermosetting adhesive, and the second thermosetting formed on the mounting surface. It comprises heating and curing the adhesive and joining the second element substrate to the mounting surface via the second thermosetting adhesive.

INDUSTRIAL APPLICABILITY According to the present invention, it is possible to provide a method for manufacturing a liquid discharge head that can suppress a step difference between element substrates adjacent to each other even when the thermal deformation of the support member is large.

It is an outline drawing of the liquid discharge head obtained in 1st Embodiment. It is a flow diagram which shows the joining process to the support member of the element substrate in 1st Embodiment. It is a top view and a side view of a support member in an initial state. It is a schematic diagram which shows the structure of the joining device. It is a step diagram which shows the method of joining the 1st to 3rd element substrates to a support member. It is an outline drawing of the liquid discharge head obtained in 2nd Embodiment. It is a flow diagram which shows the joining process to the support member of the element substrate in 3rd Embodiment.

Hereinafter, some embodiments of the present invention will be described with reference to the drawings. The liquid ejection head of this embodiment is an inkjet head mounted on a printer. Although the liquid to be ejected is ink, the present invention can be widely applied to a liquid ejection head that ejects a liquid. In the following description and drawings, the X direction is the direction parallel to the major axis direction of the liquid discharge head or the support substrate, the Y direction is the direction parallel to the discharge port forming surface and orthogonal to the X direction, and the Z direction is the discharge port forming surface. The Z direction, which is a direction orthogonal to the X direction, is orthogonal to the X direction and the Y direction.

(First Embodiment)
FIG. 1 is a schematic view showing a liquid discharge head 6 manufactured by the manufacturing method of the present embodiment. 1 (a) is a perspective view of a main part of the liquid discharge head 6, FIG. 1 (b) is a top view of FIG. 1 (a) as seen from the A direction, and FIG. 1 (c) is from the B direction of FIG. 1 (a). The side view seen is shown. The liquid discharge head 6 has a support member 1 and first to third element substrates 3A to 3C mounted on the support member 1. The support member 1 is a plate-shaped resin molded member, and can be manufactured, for example, by laminating a plurality of plates having a simple shape in the X direction.

The first to third element substrates 3A to 3C have a parallelogram shape in which the long side and the short side form an angle other than 90 degrees, and the short sides are adjacent to each other. The first to third element substrates 3A to 3C are arranged in the X direction along the long axis AX of the support member 1. The surface on which the first to third element substrates 3A to 3C of the support member 1 are mounted is referred to as a mounting surface 7. The opposite surface of the first to third element substrates 3A to 3C facing the mounting surface 7 is an ejection port forming surface 8 on which a plurality of ejection ports for ejecting ink are formed. The first to third supply paths 5A to 5C are formed at positions of the support member 1 facing the first to third element substrates 3A to 3C. The first to third supply paths 5A to 5C are through holes that penetrate the support member 1 and supply ink to the first to third element substrates 3A to 3C. FIG. 1 (c) shows a liquid discharge head 6 in a normal temperature state (for example, about 10 to 30 ° C., which is an environmental temperature generally used by a printer). Since the support member 1 is made of resin, warpage is likely to occur, and here, the support member 1 is warped in a shape recessed toward the mounting surface 7. In one example, the maximum amount of warpage is about 0.1 mm in the Z direction. The discharge port forming surface 8 of the first to third element substrates 3A to 3C and the mounting position of the first to third element substrates 3A to 3C on the mounting surface 7 are in a direction orthogonal to the mounting surface 7 (Z direction). ) Are separated by the first to third distances d1 to d3, respectively. The first to third distances d1 to d3 are set so as to cancel the warp of the support member 1. Therefore, although the support member 1 is warped, the discharge port forming surfaces 8 of the first to third element substrates 3A to 3C are on the same horizontal plane, and the recording quality can be improved.

Next, a method of joining the first to third element substrates 3A to 3C to the support member 1 will be described with reference to FIGS. 2 to 5. FIG. 2 is a flow chart showing a method of joining the first to third element substrates 3A to 3C to the support member 1. 3 (a) and 3 (b) are a top view and a side view of the support member 1 in the initial state. The initial state means a normal temperature state (that is, a state without thermal deformation) before the first to third element substrates 3A to 3C are joined. FIG. 4 is a schematic view of the joining device 40. FIG. 5 is a step diagram showing a method of joining the first to third element substrates 3A to 3C to the support member 1.

First, the support member 1 is fixed to the joining device 40 (step S1). The support member 1 is placed on the pedestal 20 and fixed in the X direction and the Y direction by the positioning pin 22 and the clamp 23. The position of the support member 1 can be recognized by using the camera 30 and the image processing device 31. The first to third thermosetting adhesives 4A to 4C are formed around the first to third supply paths 5A to 5C of the mounting surface 7 of the support member 1, respectively. The first to third thermosetting adhesives 4A to 4C are in a liquid state at this point.

Next, the warp of the mounting surface 7 of the support member 1 in the initial state is measured (step S2). The first to third reference portions 2A to 2C are provided in the vicinity of the first to third element substrates 3A to 3C on the mounting surface 7 of the support member 1. The Z-direction positions of the mounting positions of the first to third element substrates 3A to 3C can be approximated by the Z-direction positions of the first to third reference portions 2A to 2C. The positions of the first to third reference portions 2A to 2C are not particularly limited, but it is preferable to set them in the vicinity of the central portion in the X direction of the first to third element substrates 3A to 3C. The first to third reference units 2A to 2C are patterns that can be visually recognized by the camera 47 described later. Since the support member 1 is curved in a shape recessed toward the mounting surface 7, the second reference portion 2B is below the first and third reference portions 2A and 2C in the Z direction. The Z-direction positions of the first to third reference portions 2A to 2C are measured by driving the stage 21 to bring the contact-type displacement sensor 32 into contact with the first to third reference portions 2A to 2C. do. The first to third reference portions 2A to 2C are located at positions separated from the reference plane S by the initial values h1 to h3 in the Z direction. The measurement may be performed using a laser displacement meter or image processing instead of the contact type displacement sensor.

Next, as shown in FIG. 5A, the first thermosetting adhesive 4A formed on the mounting surface 7 is heat-cured, and the first element substrate 3A is subjected to the first thermosetting adhesive 4A. It is joined to the support member 1 via the (step S3). The joining device 40 has a heating finger 41 for gripping the first element substrate 3A and joining to the support member 1. The heating finger 41 is supported by an X stage 42 that moves in the X direction, a Y stage 43 that moves in the Y direction, and a θz stage 44 that rotates around the Z axis. These stages 42 to 44 operate independently and position the heating finger 41 and the first element substrate 3A gripped by the heating finger 41 at an arbitrary position on the XY plane with high accuracy. The joining device 40 includes a camera 47 for photographing the first element substrate 3A and an image processing device 48, whereby the position of the first element substrate 3A can be confirmed. The heating finger 41 can be stopped with high accuracy at an arbitrary height in the Z direction by the Z stage 45 that can move in the direction perpendicular to the mounting surface 7. In this way, the first element substrate 3A is positioned by moving the Z stage 45 in the direction perpendicular to the mounting surface 7.

A heater 46 is built in the heating finger 41. The heating finger 41 gripping the first element substrate 3A is pressed against the first thermosetting adhesive 4A, and the first thermosetting adhesive 4A is heated via the first element substrate 3A. As a result, the support member 1 is heated by the heating finger 41. The first thermosetting adhesive 4A is thermoset by heating from the heated finger 41. The first thermosetting adhesive 4A is pressed against the first element substrate 3A and deformed. When the first thermosetting adhesive 4A is heat-cured, the first element substrate 3A sandwiches the first thermosetting adhesive 4A between the support member 1 and the support member 1. Be joined. That is, the first element substrate 3A is joined to the support member 1 in a floating state at a position away from the support member 1. In one example, the temperature of the heating finger 41 is 100 ° C., and the bonding time of the first element substrate 3A is 10 seconds. Since the conditions for joining the first element substrate 3A to the support member 1 differ depending on the curing temperature and thickness of the first thermosetting adhesive 4A, the temperature of the heating finger 41 and the temperature of the first element substrate 3A It is preferable to set the joining time as appropriate. Since the support member 1 has not undergone thermal deformation at the time of adhering the first element substrate 3A, it is not necessary to execute step S4 described later in advance, and the first element substrate 3A is performed as in step S5 described later. There is no need to adjust the joint position of. The Z stage 45 of the heating finger 41 is stopped at the point P1 so that the first element substrate 3A is bonded at a desired Z direction position, and the first element substrate 3A is bonded to the support member 1.

After the end of step S3, as shown in FIG. 5B, the displacement sensor 32 is used to measure the amount of change in the Z-direction position of the second reference portion 2B (step S4). This step is preferably performed at the timing immediately before joining the second element substrate 3B to the support member 1. Since the heating finger 41 and the displacement sensor 32 are arranged coaxially, steps S3 and S4 can be performed without driving the stage 21. The support member 1 is deformed in a shape that is convex upward due to thermal deformation due to heating. That is, the Z-direction position of the second reference portion 2B (the mounting position of the second element substrate 3B on the mounting surface 7 of the support member 1) is set after the first element substrate 3A is joined to the mounting surface 7 (the first). (Before and after joining the element substrate 3A of 1 to the mounting surface 7), the element substrate 3A is displaced upward in the Z direction from the initial position. By obtaining the change from the initial value h2 measured in step S2 of the Z-direction distance H2 from the reference plane S measured in this step, the amount of change Δh2 = h2-H2 in the Z-direction position of the second reference portion 2B. (Predetermined amount of change) is measured.

Next, as shown in FIG. 5C, the second thermosetting adhesive 4B formed on the mounting surface 7 is heat-cured, and the second element substrate 3B is the second thermosetting adhesive 4B. It is joined to the support member 1 via the (step S5). The support member 1 is thermally deformed by heating the first thermosetting adhesive 4A. The Z stage 45 stops at the point P2 (= P1-Δh2) in which the point P1 when the first element substrate 3A is joined is corrected by the thermal deformation amount Δh2 of the support member 1. Therefore, when the second element substrate 3B is joined to the support member 1, the discharge port forming surface 8 of the second element substrate 3B is only Δh2 upward in the Z direction from the position when the support member 1 is not thermally deformed. It is in a displaced position. That is, when the second element substrate 3B is joined to the support member 1, the second element substrate 3B is positioned so as to maintain the second distance d2.

After the end of step S5, as shown in FIG. 5D, the displacement sensor 32 is used to measure the amount of change in the Z-direction position of the third reference unit 2C (step S6). This step is preferably performed at the timing immediately before joining the third element substrate 3C. The support member 1 is deformed so as to be convex upward due to thermal deformation due to heating. That is, the Z-direction position of the third reference portion 2C (the mounting position of the third element substrate 3C on the mounting surface 7 of the support member 1) is initially set after the second element substrate 3B is joined to the mounting surface 7. It is displaced upward in the Z direction from the position. By obtaining the change from the initial value h3 measured in step S2 of the Z-direction distance H3 from the reference plane S measured in this step, the amount of change Δh3 = h3-H3 in the Z-direction position of the third reference unit 2C. (Predetermined amount of change) is measured.

Next, as shown in FIG. 5 (e), the third thermosetting adhesive 4C formed on the mounting surface 7 is heat-cured, and the third element substrate 3C is replaced with the third thermosetting adhesive 4C. It is joined to the support member 1 via the (step S7). The support member 1 is thermally deformed by heating the first thermosetting adhesive 4A. The Z stage 45 stops at the point P3 (= P1-Δh3) in which the point P1 when the first element substrate 3A is joined is corrected by the thermal deformation amount Δh3 of the support member 1. When the third element substrate 3C is joined to the support member 1, the discharge port forming surface 8 of the third element substrate 3C is displaced upward by Δh3 in the Z direction from the position when the support member 1 is not thermally deformed. In position. That is, when the third element substrate 3C is joined to the support member 1, it is positioned so as to maintain the third distance d3. After that, the support member 1 is cooled. As shown in FIG. 5 (f), the discharge port forming surfaces 8 of the first to third element substrates 3A to 3C are arranged on the same horizontal plane.

The effect of this embodiment will be described. If a step is generated due to the Z-direction positions of adjacent element substrates being displaced from each other, the position at which the ejected droplets land on the recording medium may be displaced, causing color unevenness or streaks. In particular, since the resin support member 1 has a large coefficient of linear thermal expansion, large thermal deformation occurs in the process of arranging the element substrates by the heating finger 41. Even if the heights of the adjacent element boards are aligned and joined, the height of the element boards changes when the thermal deformation of the support member 1 disappears, and a step is generated at the connecting portion of the adjacent element boards. Further, since the internal stress is different for each support member 1, there are individual differences in thermal deformation. Therefore, even if the height at which the element substrates are joined is corrected by assuming the amount of deformation of the support member 1 in advance, the above-mentioned problems cannot be sufficiently dealt with. In the present embodiment, the thermal deformation is measured for each support member 1, and the height at which the element substrates are joined is controlled according to the result. In particular, since the thermal deformation of the support member 1 is measured at the timing immediately before joining the element substrates, it is possible to suppress the deviation of the element substrate in the height direction when it is cooled. In the page-wide type liquid discharge head in which a plurality of element substrates are arranged on the support member 1 over a length equal to or longer than the width of the recording medium, since many element substrates are arranged in series, the support member 1 becomes long and the thermal deformation is large. Become. This embodiment can be particularly preferably applied to a page-wide type liquid discharge head.

(Second embodiment)
In the present embodiment, after the first to third element substrates 3A to 3C are joined to the mounting surface 7 and the support member 1 is cooled, the position of the discharge port forming surface 8 of the second element substrate 3B in the Z direction is set. , The position of the discharge port forming surface 8 of the first and third element substrates 3C in the Z direction is different. That is, as shown in FIG. 6, the first to third element substrates 3A to 3C are located on the curved surface C along the mounting surface 7. Other than that, it is the same as that of the first embodiment. When the discharge port forming surfaces 8 of all the element substrates are aligned at the same height as in the first embodiment, the amount of crushing of the thermosetting adhesive differs between the element substrates adjacent to each other. For example, in the case of the first embodiment, the amount of crushing of the thermosetting adhesives 4A and 4C is large in the first and third element substrates 3A and 3C, and the thermosetting adhesive 4B is used in the second element substrate 3B. The amount of crushing becomes smaller. In a device substrate with a large amount of crushing, there is a high possibility that the thermosetting adhesive will invade the supply path. In the present embodiment, the first and third element substrates 3C are supported at positions above the Z direction from the first embodiment within an allowable range of the amount of the thermosetting adhesive penetrating the supply paths 5A to 5C. Join to member 1. When a large number of element boards are joined to the support member 1, the heights of the plurality of element boards in the Z direction are changed stepwise in order to prevent a large step from being generated only in a part of the connecting portion of the adjacent element boards. , It is preferable to average the amount of steps.

(Third embodiment)
FIG. 7 is a flow chart showing a step of joining the element substrate to the support member in the third embodiment. In the present embodiment, the position of the second element substrate 3B is modified so as to maintain the second distance d2 while the second thermosetting adhesive 4B is heat-cured. Other than that, it is the same as that of the first embodiment. Steps S1 to S4 are performed in the same manner as in the first embodiment. In step S5, joining of the second element substrate 3B to the support member 1 is started. In step S6, the Z-direction position H2 of the second reference portion 2B is measured during the joining of the second element substrate 3B to the support member 1. In step S7, the stop point of the Z stage 45 of the heating finger 41 is controlled according to the amount of change in the Z direction position H2 of the second reference portion 2B measured. In one example, while the second element substrate 3B is joined to the support member 1, the Z-direction position H2 of the second reference portion 2B is measured at 1-second intervals, and the Z-direction position H2 is 0 from the initial value at the start of joining. When the change is .005 mm or more, the stop point of the Z stage 45 is driven by 0.005 mm. The same applies to the joining of the third element substrate 3C. First, the amount of change in the Z-direction position of the third reference unit 2C is measured (step S8). Next, joining of the third element substrate 3C to the support member 1 is started (step S9). In step S10, the Z-direction position H3 of the third reference portion 2C is measured during the joining of the third element substrate 3C to the support member 1. In step S11, the stop point of the Z stage 45 of the heating finger 41 is controlled according to the amount of change in the Z direction position H3 of the third reference unit 2C measured. Since this embodiment controls the position of the element substrate according to the progress of thermal deformation of the support member 1 even during joining, it is suitably applied to a method for manufacturing a liquid discharge head 6 in which the thermal deformation of the support member 1 is large. Can be done.

Although the present invention has been described above by embodiment, the present invention is not limited to these embodiments. For example, the element substrate may be a unit in which an ink ejection device and a flexible wiring board are bonded to a plate, and electrical connections and electrical connection portions are sealed with an insulating material. The unit form is not limited to this, and may be any form. Further, in the present embodiment, the element substrates are arranged in-line (straight line), but they can also be arranged in a staggered manner. In the present embodiment, the support member 1 is deformed so as to warp upward, but the deformation pattern is not limited to this, and may be a pattern warping downward or a pattern deforming in a wavy shape.

1 Support member 3A to 3C 1st to 3rd element substrates 4A to 4C 1st to 3rd thermosetting adhesive 7 Mounting surface 8 Discharge port forming surface

Claims (11)

The first element substrate and the second element substrate are mounted on the mounting surface of the support member, and the discharge port forming surface of the second element substrate and the mounting position of the second element substrate on the mounting surface are set. A method for manufacturing a liquid discharge head separated by a second distance in a direction orthogonal to the mounting surface.
The first thermosetting adhesive formed on the mounting surface is heat-cured, and the first element substrate is bonded to the mounting surface via the first thermosetting adhesive.
In a state where the support member is thermally deformed by heating of the first thermosetting adhesive, the second element substrate is positioned so as to maintain the second distance, and the second element substrate is formed on the mounting surface. 2. A method for manufacturing a liquid discharge head, comprising: heat-curing the thermosetting adhesive of 2 and joining the second element substrate to the mounting surface via the second thermosetting adhesive. The mounting position of the second element substrate on the mounting surface is predetermined in the first direction from the position when the support member is not thermally deformed after the first element substrate is joined to the mounting surface. When the second element substrate is joined to the support member, the discharge port forming surface of the second element substrate changes from the position when there is no thermal deformation of the support member. The method for manufacturing a liquid discharge head according to claim 1, wherein the liquid discharge head is located at a position displaced by the predetermined amount of change in the first direction. The support member is warped so that the mounting surface is curved, and the mounting surface is preliminarily warped in order to determine the position of the discharge port forming surface of the second element substrate when there is no thermal deformation. The method for manufacturing a liquid discharge head according to claim 2, wherein the liquid discharge head is measured. A second reference portion is provided in the vicinity of the mounting position of the second element substrate of the support member, and the position of the second reference portion before and after the first element substrate is joined to the mounting surface. The method for manufacturing a liquid discharge head according to claim 2 or 3, wherein the predetermined amount of change is measured by measuring the change. Any one of claims 1 to 4, wherein the position of the second element substrate is modified so as to maintain the second distance while the second thermosetting adhesive is heat-cured. The method for manufacturing a liquid discharge head according to the section. The third element substrate is mounted on the mounting surface of the support member, and the discharge port forming surface of the third element substrate and the mounting position of the third element substrate on the mounting surface are orthogonal to each other. A method for manufacturing a liquid discharge head at a distance of a third distance.
In a state where the support member is thermally deformed by heating of the second thermosetting adhesive, the third element substrate is positioned so as to maintain the third distance, and the third element substrate is formed on the mounting surface. Any one of claims 1 to 5, wherein the thermosetting adhesive of 3 is heat-cured and the third element substrate is bonded to the mounting surface via the third thermosetting adhesive. The method for manufacturing a liquid discharge head according to the section. The discharge port forming surface of the first to third element substrates is located on the same horizontal plane after the third element substrate is joined to the mounting surface and the thermal deformation of the support member is eliminated. The method for manufacturing a liquid discharge head according to claim 6. The discharge port forming surface of the first to third element substrates is formed on a curved surface along the mounting surface after the third element substrate is joined to the mounting surface and the support member is not thermally deformed. The method for manufacturing a liquid discharge head according to claim 6, which is located in the above. The method for manufacturing a liquid discharge head according to any one of claims 1 to 8, wherein each element substrate is gripped by a heating finger having a built-in heater, and the support member is heated by the heating finger. The ninth aspect of the present invention, wherein the heating finger is mounted on a stage that can move in a direction perpendicular to the mounting surface, and each element substrate is positioned by moving the stage in the direction perpendicular to the mounting surface. A method for manufacturing a liquid discharge head. The first element substrate and the second element substrate are mounted on the mounting surface of the support member, and the discharge port forming surface of the second element substrate and the mounting position of the second element substrate on the mounting surface are set. A device for manufacturing a liquid discharge head separated by a second distance in a direction orthogonal to the mounting surface.
A heating finger with a built-in heater while grasping the first and second element substrates and joining them to the mounting surface.
It has a stage that moves the heated finger in a direction perpendicular to the mounting surface.
The heated finger heat-cures a first thermosetting adhesive formed on the mounting surface, and the first element substrate is bonded to the mounting surface via the first thermosetting adhesive. Then, the second thermosetting adhesive formed on the mounting surface is heat-cured, and the second element substrate is bonded to the mounting surface via the second thermosetting adhesive.
The stage is a liquid discharge that positions the second element substrate so as to maintain the second distance in a state where the support member is thermally deformed by heating of the first thermosetting adhesive. Head manufacturing equipment.

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