JP2021146525A - Liquid discharge head and method for manufacturing the same - Google Patents

Abstract

To provide a liquid discharge head that can readily perform coating with a resin agent with respect to a marginal part of an opposed surface to a support member of an element substrate, and to provide a method for manufacturing a liquid discharge head.SOLUTION: In a liquid discharge head, a resin agent is provided in a clearance between a marginal part of an element substrate and a support member so as to coat the marginal part of the element substrate, a groove extending in a direction inclined to a direction in which the marginal part of the element substrate extends is provided at a lateral surface of the support member, and the resin agent is provided so as to be connected to the clearance from an inside of the groove.SELECTED DRAWING: Figure 3

Description

The present invention relates to a liquid discharge head that discharges a liquid and a method for manufacturing the same.

As a liquid discharge head for discharging a liquid, a recording element substrate (element substrate) provided with a recording element that applies energy for discharging the liquid to the liquid, a support member that supports the recording element substrate, and a recording element substrate are electrically connected to each other. There is known a configuration having a wiring board provided with electrical wiring.

Patent Document 1 discloses a configuration in which the recording element substrate and the support member are joined so that the end portion of the recording element substrate protrudes from the support member. Such a configuration is particularly suitable for a long liquid discharge head such as a full-line type head because the ends of a plurality of recording element substrates can be arranged close to each other without being hindered by the support member. Is. Further, in such a configuration in which the end portion of the recording element substrate protrudes from the support member, the end portion of the facing surface facing the support member of the recording element substrate also protrudes from the support member, and the edge portion of the facing surface protrudes from the support member. It may be exposed to the outside without being joined to.

JP-A-2017-205903

When the edge of the surface facing the support member of the element substrate is exposed to the outside as described above, the liquid (ink) adheres to the portion and various constituent materials on the surface facing the element substrate swell. There is a risk of deformation or elution. Therefore, it is preferable to coat the edge of the device substrate with a resin agent having sufficient resistance to a liquid such as ink, and it is preferable to coat the element substrate with the resin agent by a simple method.

Therefore, an object of the present invention is to provide a liquid discharge head and a method for manufacturing a liquid discharge head, which can easily cover the edge of the surface of the element substrate facing the support member with a resin agent.

In order to solve the above problems, the liquid discharge head of the present invention includes an element substrate provided with an element that applies energy for discharging the liquid to the liquid, and a support member to which the element substrate is bonded via an adhesive. In the liquid discharge head having, the edge portion of the surface of the element substrate facing the support member is not joined to the support member via the adhesive, and the edge portion of the element substrate and the support are provided. A resin agent is provided in the gap between the members so as to cover the edge portion of the element substrate, and the side surface of the support member is oriented in the extending direction of the edge portion of the element substrate. A groove extending in an inclined direction is provided, and the resin agent is provided so as to connect from the inside of the groove to the gap.

According to the present invention, it is possible to provide a liquid discharge head and a method for manufacturing a liquid discharge head, which can easily cover the edge of the surface of the element substrate facing the support member with a resin agent.

Top view and side view showing the inkjet recording head of this embodiment Sectional drawing which shows the inkjet recording head of this embodiment The figure which shows the state which the sealant applied to the groove of a support member flows. The figure which shows the modification of this embodiment Diagram for explaining the posture of applying the sealant

Embodiments to which the present invention can be applied will be described with reference to the drawings.

1A and 1B are views showing an inkjet recording head 1 as a liquid discharge head of the present embodiment, FIG. 1A is a top view thereof, and FIG. 1B is a side view thereof. FIG. 2 is a cross-sectional view taken along the line AA of FIG. 1 (a), FIG. 2 (a) shows a state before the sealant 8 described later is applied, and FIG. 2 (b) shows the state before the sealant 8 is applied. The state after the above is shown.

The inkjet recording head 1 includes a recording element substrate 2 provided with a discharge port for ejecting ink and a recording element for imparting energy for ejecting ink to ink, a first support member 3 for supporting the recording element substrate 2, and a first support member 3 for supporting the recording element substrate 2. It has a second support member 4 that supports the first support member 3. Further, the inkjet recording head 1 has a wiring board 5 provided with electrical wiring, and a pad portion provided on both edge portions on the surface side of the recording element substrate 2 and an electrical wiring of the wiring board 5 are wired. And are electrically connected by flying leads. In order to protect the electric connection part including the pad part, the electric wiring, and the wire from ink, the electric connection part is coated with the sealant 6. Two types of sealants are used to seal the electrical connection, a low-viscosity sealant is provided on the lower side of the wire or flying lead, and a high-viscosity sealant is provided on the upper side. You may.

The recording element substrate 2 has a recording element, a protective film, and the like on the front surface side of the silicon substrate, and ink provided on the silicon substrate on the back surface side (the side facing the first support member 3). It has a resin film 9 for protecting the flow path. The resin film 9 is provided so as to cover at least a part of the recording element substrate 2 on the facing surface side. The resin film 9 provided on the recording element substrate 2 and the first support member 3 are joined via an adhesive 10.

Here, as shown in FIG. 2, the recording element substrate 2 is joined to the first support member 3 with its end portion protruding from the first support member 3. Such a configuration is suitable for a long liquid discharge head because the ends of the plurality of recording element substrates 2 can be arranged close to each other without being hindered by the first support member 3. By arranging a plurality of inkjet recording heads 1 shown in FIG. 1A in the arrangement direction of the recording elements, a long head such as a full-line type head can be configured.

However, as shown in FIG. 2A, in the above configuration, the edge portion 2a (the portion surrounded by the dotted line) of the surface of the recording element substrate 2 facing the first support member 3 is the first support. Since it is not joined to the member 3, a part of the resin film 9 of the recording element substrate 2 is exposed to the outside. When ink adheres to the exposed resin film 9, the resin film 9 may swell and be deformed or eluted, resulting in ink leakage. Therefore, as shown in FIG. 2B, in the present embodiment, the portion of the resin film 9 that is not bonded to the first support member 3 is bonded to the sealant 8 (which is resistant to corrosion against liquids such as ink). Cover with resin agent). As a result, it is possible to suppress the adhesion of ink to the edge portion 2a of the surface of the recording element substrate 2 facing the support member 3.

As shown in FIG. 2, it is preferable that the gap 11 has a shape that widens toward the outside (direction away from the joint portion between the recording element substrate 2 and the first support member 3). As a result, the sealing agent 8 easily enters the gap 11 between the edge portion 2a of the recording element substrate 2 and the first support member 3, and the sealing agent 8 for the exposed portion of the edge portion 2a of the recording element substrate 2. This is because good coating is possible. Such a shape can be formed, for example, by C chamfering at least a part of the ridge line forming the surface of the first support member 3 facing the recording element substrate 2.

As the sealing agent 8, it is preferable to use a liquid epoxy resin, acrylic resin, epoxy acrylate resin, imide resin, amide resin or the like. Further, the sealant 8 has a low viscosity so that the exposed portion of the resin film 9 can be covered by flowing the joint surface between the recording element substrate 2 and the first support member 3 by surface tension. desirable. Specifically, the viscosity of the sealant 8 is preferably about 0.1 to 100 Pa · s, more preferably about 1 to 80 Pa · s. Further, as the sealing agent 8, it is preferable to use a material having higher corrosion resistance to liquid than the resin film 9. Further, from the viewpoint of cost, it is preferable to use a material common to the sealing agent that seals the electrical connection portion between the recording element substrate 2 and the wiring substrate 5. In particular, in a configuration in which two types of sealants are used for the electrical connection portion, since the sealant provided on the lower side of the wire or the like has a low viscosity, this and the sealant 8 should be used as a common material. Is preferable.

Next, a method of applying the sealant 8 will be described. In order to cover the exposed edge 2a of the recording element substrate 2 with the sealing agent 8, the sealing agent 8 is applied to the entire gap between the edge 2a of the recording element substrate 2 and the first support member 3. A method is conceivable. However, it is difficult to directly apply the sealant 8 to such a fine gap portion over the entire area, and a device for realizing high-definition coating is required, so that there is a concern that the cost will increase. There is.

Further, it is also conceivable to apply the required amount of the sealing agent 8 to the gap portion by dividing it into several places and applying it in dots. In this method, the sealing agent 8 flows through the gap portion due to surface tension, and the sealing agents 8 which are divided and applied to a plurality of places flow and merge with each other, and the edge portion 2a of the recording element substrate 2 is sealed. It is coated with a stop agent 8. However, it is uncertain whether the point-coated sealant 8 flows in the left-right direction with respect to the gap. When the sealant 8 first comes into contact with the sealant 8 applied to the adjacent one-sided portion, it becomes easier to flow toward the contacted side and less likely to flow to the other side. Then, the sealing agent 8 is not connected to the sealing agent 8 applied to the adjacent other side portion, and an exposed portion remains without being covered with the sealing agent 8 at the edge portion 2a of the recording element substrate 2. There is a fear. Therefore, there is a possibility that the load on the manufacturing process may increase, such as checking the presence or absence of the exposed portion or separately applying the sealing agent 8 to the exposed portion. On the other hand, if the amount of the sealant 8 is increased in order to prevent the occurrence of such an exposed portion, the sealant 8 protrudes and the sealant 8 adheres to an unnecessary portion of the recording element substrate 2. There is a risk of doing.

Therefore, in the present embodiment, a groove 7 is provided on the side surface of the first support member 3, and the edge 2a of the recording element substrate 2 is covered with the sealing agent 8 by using the groove 7. FIG. 3 is an enlarged view of the region B of FIG. 1 (b), FIG. 3 (a) shows a state before the sealant 8 is applied to the groove 7, and FIGS. 3 (b) to 3 (d) are shown. It is a figure which shows the state that the sealing agent 8 applied to a groove 7 flows into a gap 11.

The groove 7 extends in a direction inclined with respect to the extending direction of the edge portion 2a of the recording element substrate 2 (direction of arrow C in FIG. 3A). When the sealing agent 8 is applied to the inside of the groove 7 (FIG. 3B), the sealing agent 8 flows along the inclination direction of the groove 7, and further, from the groove 7, the edge 2a of the recording element substrate 2 and the second It reaches the gap 11 between the support member 3 of 1 and the support member 3. The sealant 8 that has reached the gap 11 stays in the gap 11 due to its surface tension and flows through the gap 11 (FIG. 3 (c)). At this time, the sealing agent 8 is difficult to flow in the direction in which the angle formed by the groove 7 and the gap 11 (the angle formed by the groove 7 and the edge portion 2a) is an acute angle, and easily flows in the direction in which the angle is obtuse. Therefore, after reaching the gap 11, the sealing agent 8 tends to flow in the right direction of FIG. 3C. Then, the gap 11 is filled with the sealing agent 8, and the edge portion 2a of the recording element substrate 2 including the resin film 9 described above is covered with the sealing agent 8. In this state, since a small amount of the sealant 8 remains in a part of the groove 7, the sealant 8 inside the groove 7 and the sealant 8 provided in the gap 11 are connected (FIG. 3 (d)). ).

In this way, by providing a groove 7 that is inclined with respect to the edge portion 2a of the recording element substrate 2 and flowing the sealing agent 8 through the groove 7, the sealing agent is directed in a predetermined direction by utilizing the inclination of the groove 7. 8 can be flowed. As a result, the sealant 8 can easily flow through the gap 11 between the edge portion 2a of the recording element substrate 2 and the first support member 3, and the edge portion 2a of the recording element substrate 2 can be easily formed by the sealant 8. Can be covered.

Further, by aligning the inclination directions of the plurality of grooves 7 as in the present embodiment, the sealing agent 8 that has reached the gap 11 from the grooves 7 can easily flow in a certain direction. In the present embodiment, as an example, five grooves 7 having a width of 1 mm and a pitch of 4 mm are provided so that the inclination angle D is about 45 °. Here, the inclination angle refers to an acute angle among the angles formed by the extending direction of the edge portion 2a of the recording element substrate 2 and the extending direction of the groove 7. Here, in order to utilize the above-mentioned phenomenon that the sealing agent 8 easily flows to the obtuse angle side, it is preferable that the inclination angle D of the groove 7 with respect to the extending direction of the edge portion 2a is 70 ° or less. Further, in order to facilitate the flow of the sealant 8 from the groove 7 toward the gap 11 without accumulating the sealant 8 in the groove 7, the inclination angle D is preferably 20 ° or more. The number, width, inclination angle, etc. of the grooves 7 are not limited to the configuration of the present embodiment, and the grooves 7 may be provided as appropriate according to the dimensions of the portion where the sealant 8 needs to be applied, the volume of the gap, and the like. good.

In the configuration in which the plurality of grooves 7 are provided as in the present embodiment, the adjacent sealing agents 8 can be easily connected to each other, so that the gap between the edge portion 2a of the recording element substrate 2 and the first support member 3 is provided. This is preferable because the sealing agent 8 can easily flow over the entire area of 11. Further, in order to make it difficult for the applied sealing agent 8 to embrace bubbles, it is preferable that the groove 7 has an R shape.

FIG. 4 shows a modified example of this embodiment. FIG. 4 shows a side view of the inkjet recording head 1, and is a view corresponding to FIG. 1 (b). In FIG. 4A, the direction and angle of inclination of the groove 7 differ depending on the position of the groove 7. Specifically, the grooves 7 are provided so that the plurality of grooves 7 are inclined toward the central portion in the extending direction of the edge portion 2a of the recording element substrate 2. Such a configuration is advantageous when a portion not covered by the sealant 8 is likely to occur in the central portion. FIG. 4B has a shape in which the width of the groove 7 narrows toward the gap 11, and such a shape makes it easier for the sealant 8 to flow from the groove 7 to the gap 11. ..

Further, the work in which the recording element substrate 2 and the first support member 3 are joined is placed on the surface of the recording element substrate 2 (first support member) so that the sealant 8 can easily flow from the groove 7 to the gap 11. It is preferable to apply the sealant 8 to the groove 7 in a posture in which the back surface of the surface facing the surface of the groove 7 faces downward. Further, it is preferable to apply the sealant 8 to the groove 7 in a posture in which the surface of the recording element substrate 2 is tilted from the horizontal state so that the sealant 8 can be easily applied from the needle 12 (FIG. 5). Therefore, it is more preferable to apply the sealant 8 to the groove 7 in a posture in which the surface of the recording element substrate 2 is tilted at 30 ° or more and 60 ° or less, and it is possible to apply the sealing agent 8 in a posture in which the surface is tilted by about 45 °. More preferred.

After applying the sealant 8, the sealant 8 is cured by heat treatment. In this curing step, it is preferable that the surface of the recording element substrate 2 faces downward (horizontal state). If thermosetting is performed in an inclined posture, the sealing agent 8 flows downward due to gravity, and the sealing agent 8 cannot cover the desired region, or the sealing agent 8 adheres to unnecessary parts. This is because there is a risk of it.

1 Inkjet recording head 2 Recording element substrate 3 First support member 7 Groove 8 Encapsulant 9 Resin film 10 Adhesive

Claims (9)

An element substrate provided with an element that imparts energy for discharging the liquid to the liquid, and
With the support member to which the element substrate is bonded via an adhesive,
In the liquid discharge head having
The edge of the surface of the element substrate facing the support member is not joined to the support member via the adhesive, and in the gap between the edge portion of the element substrate and the support member. , A resin agent is provided so as to cover the edge portion of the element substrate.
A groove extending in a direction inclined with respect to the extending direction of the edge portion of the element substrate is provided on the side surface of the support member.
A liquid discharge head characterized in that the resin agent is provided so as to be connected to the gap from the inside of the groove. The liquid discharge head according to claim 1, wherein a plurality of the grooves are provided on the side surface of the support member. The liquid discharge head according to claim 2, wherein the plurality of grooves are oriented so as to incline with each other. The liquid discharge head according to any one of claims 1 to 3, wherein the inclination angle of the groove with respect to the extending direction of the edge portion is 70 ° or less. The liquid discharge head according to any one of claims 1 to 4, wherein the inclination angle of the groove with respect to the extending direction of the edge portion is 20 ° or more. The element substrate is provided with a resin film on a surface facing the support member.
The liquid discharge head according to any one of claims 1 to 5, wherein the resin agent covers the resin film located at the edge portion of the element substrate. The liquid discharge head according to any one of claims 1 to 6, wherein the gap widens toward a direction away from the joint portion between the element substrate and the support member. An element substrate provided with an element that imparts energy for discharging the liquid to the liquid, and
With the support member to which the element substrate is bonded via an adhesive,
In the method of manufacturing a liquid discharge head having
The edge of the surface of the element substrate facing the support member is not joined to the support member via the adhesive.
A groove extending in a direction inclined with respect to the extending direction of the edge portion of the element substrate is provided on the side surface of the support member.
A method for manufacturing a liquid discharge head, which comprises applying a resin agent to the groove and flowing the resin agent from the groove into a gap between the edge portion of the element substrate and the support member. The method for manufacturing a liquid discharge head according to claim 8, wherein the resin agent is applied to the groove in a state where the back surface of the element substrate facing the support member is tilted downward.

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