JP2022075335A - Liquid discharge head - Google Patents

Abstract

To provide a liquid discharge head capable of securing strength of a substrate, while preventing liquid consumption amounts from deviating between liquid supply ports.SOLUTION: A liquid discharge head comprises: a discharge port forming member 4 forming discharge ports 5 for discharging liquid; a substrate 1 having a plurality of liquid supply ports 7 for supplying liquid to the discharge ports 5 and partition walls 19 formed between the plurality of liquid supply ports; and a support member 18 for supporting the substrate 1. In a view from a position opposite to a main surface 20 of the substrate 1, the liquid supply port 7 extends in a longitudinal direction of the substrate 1, and the plurality of liquid supply ports 7 are arrayed in a shorter direction of the substrate 1. At least a part of the partition walls 19 are non-abutting portions 19a not abutting on the support member 18. In a view from a position opposite to the main surface 20 of the substrate 1, also an opening width at any place of the liquid supply port 7 is equal to or smaller than an opening width on a side of the liquid supply port 7.SELECTED DRAWING: Figure 3

Description

The present invention relates to a liquid discharge head.

An inkjet printer is mentioned as an example of a liquid ejection device (recording apparatus) that ejects a liquid onto a recording medium such as paper to perform recording. The inkjet printer includes a liquid ejection head which is a portion for ejecting a liquid (ink). A liquid discharge head is generally a recording element having a discharge port forming member in which a plurality of discharge ports for discharging liquid are formed, and a substrate in which a liquid supply port for supplying liquid to the discharge port is formed. It has a board.

Patent Document 1 discloses a recording element substrate in which a plurality of liquid supply ports are individually and independently formed on the substrate, as shown in FIG. 8 (a) is a plan view when the substrate is viewed from a position facing the main surface 20 of the substrate 1, and FIG. 8 (b) is a cross section in the AA'cross section shown in FIG. 8 (a). It is a figure. The liquid is supplied from the ink tank containing the liquid (ink) to the discharge port 5 via the liquid supply port 7.

Japanese Unexamined Patent Publication No. 2007-269016

Depending on the recording pattern (printing pattern), a large amount of liquid may be discharged from a specific discharge port. In this case, if a plurality of liquid supply ports as shown in FIG. 8 are formed independently of each other, more liquid is consumed from the liquid supply port communicating with the specific discharge port. As a result, the liquid in the ink tank connected to the liquid supply port runs out of ink earlier than other ink tanks. Therefore, even though the other ink tanks are sufficiently filled with liquid, the liquid cannot be discharged from a specific ejection port, so the liquid ejection head itself is replaced with a new one. You may have to.

Therefore, a configuration in which a plurality of liquid supply ports 7 are communicated with each other as shown in FIG. 9 can be considered. 9 (a) is a plan view corresponding to FIG. 8 (a), and FIG. 9 (b) is a cross-sectional view taken along the line AA'shown in FIG. 9 (a). As shown in FIG. 9B, a plurality of liquid supply ports 7 communicate with each other. This communication between the liquid supply ports occurs over the longitudinal direction (Y direction) of the substrate 1. By communicating the plurality of liquid supply ports 7 with each other, even if the consumption of the liquid from the specific discharge port is intense, the liquid can be supplied from the other liquid supply ports 7. Therefore, it is possible to avoid a case where the liquid consumption becomes intense only in a specific ink tank. However, in the configuration shown in FIG. 9, in order to allow the plurality of liquid supply ports 7 to communicate with each other, the partition wall 19 formed between the liquid supply ports is scraped and removed by etching or the like, so that the strength of the substrate 1 is strong. Decreases. When the strength of the substrate 1 is lowered, cracks 12 may occur in the substrate 1 when an external force 13 or the like is applied to the substrate 1.

Therefore, in view of the above problems, it is an object of the present invention to provide a liquid discharge head capable of ensuring the strength of the substrate while suppressing the bias of the liquid consumption between the liquid supply ports.

In order to solve the above problems, the present invention comprises a discharge port forming member that forms a discharge port for discharging a liquid, a plurality of liquid supply ports for supplying liquid to the discharge port of the discharge port forming member, and the above. A liquid discharge head including a substrate having a partition wall formed between a plurality of liquid supply ports and a support member for supporting the substrate, when viewed from a position facing the main surface of the substrate. The liquid supply port extends along the longitudinal direction of the substrate, and when viewed from a position facing the main surface of the substrate, the plurality of liquid supply ports extend along the lateral direction of the substrate. At least a part of the partition wall is a non-contact portion that does not abut on the support member, and the liquid supply ports formed adjacent to each other among the plurality of liquid supply ports are located between the liquid supply ports. , The non-contact portion and the support member communicate with each other, and when the cross section of the liquid supply port in the lateral direction is viewed, the opening width at any of the liquid supply ports is also the liquid supply. It is characterized in that it is equal to or less than the opening width of the mouth on the support member side.

According to an object of the present invention, it is an object of the present invention to provide a liquid discharge head capable of ensuring the strength of a substrate while suppressing a bias in the amount of liquid consumed between liquid supply ports.

The perspective view which shows the liquid discharge head. The perspective view which shows the recording element substrate. Schematic diagram of a recording element substrate. The schematic diagram which shows each process of the manufacturing method of a recording element substrate. The schematic diagram which shows the recording element substrate in 2nd Embodiment. The schematic diagram which shows the recording element substrate in 2nd Embodiment. The schematic diagram which shows the modification of the recording element substrate in 2nd Embodiment. The schematic diagram which shows the recording element substrate of the conventional example. The schematic diagram which shows the recording element substrate of the comparative example.

Hereinafter, embodiments of the present invention will be described in detail.

(First Embodiment)
The first embodiment will be described with reference to FIGS. 1 to 4. FIG. 1 is a perspective view showing the liquid discharge head 16 of the present embodiment. As shown in FIG. 1, the liquid discharge head 16 accommodates a recording element substrate 15 having a discharge port 5 (FIG. 2) for discharging liquid, a flexible wiring board 17, and ink to be supplied to the discharge port 5. It is mainly composed of a housing 18. The flexible wiring board 17 has wiring for supplying electric power to the recording element board 15. Since the housing 18 is also a member that supports the recording element substrate 15, it may be referred to as a support member in the following description.

FIG. 2 is a perspective view showing the recording element substrate 15. The recording element substrate 15 is formed with energy generating elements 14 that generate energy for discharging the liquid from the ejection port 5 at a predetermined pitch. Further, the substrate 1 is formed with a plurality of liquid supply ports 7 for supplying the liquid from the housing 18 to the discharge port 5. The substrate 1 is made of, for example, silicon. In particular, a silicon single crystal substrate is preferable. A discharge port 5 corresponding to each energy generating element 14 is formed on the substrate 1 by the discharge port forming member 4. The discharge port forming member 4 is required to have high mechanical strength as a structural material, adhesion to a substrate, ink resistance, and resolution for patterning a fine pattern as the discharge port 5. Is preferable. Examples of the material satisfying these characteristics include a cationically polymerized epoxy resin composition. Examples of the epoxy resin include a reaction product of bisphenol A and epichlorohydrin, and a reaction product of bromo-containing bisphenol A and epichlorohydrin. In addition, phenol novolak or a reaction product of o-cresol novolak and epichlorohydrin can be mentioned. The epoxy resin preferably has an epoxy equivalent of 2000 or less, and more preferably an epoxy equivalent of 1000 or less.

Examples of the photocationic polymerization initiator for curing the epoxy resin include compounds that generate an acid by light irradiation. For example, aromatic sulfonium salt and aromatic iodinenium salt can be mentioned. Further, a wavelength sensitizer may be added if necessary. Examples of the wavelength sensitizer include SP-100 commercially available from ADEKA CORPORATION.

In addition to being manufactured of such a resin, the discharge port forming member 4 can also be formed of, for example, a silicon substrate, a metal layer, or an inorganic film such as SiN.

FIG. 3A is a plan view of the recording element substrate 15 as viewed from the substrate 1 side. FIG. 3B is a cross-sectional view taken along the line AA'shown in FIG. 3A. As shown in FIG. 3A, a plurality of liquid supply ports are arranged along the lateral direction (X direction) of the substrate 1, and a partition wall 19 is formed between the liquid supply ports. The partition wall 19 is a part of the substrate. In the cross section shown in FIG. 3B, since a part of the partition wall 19 is removed, the liquid supply ports communicate with each other. That is, when viewed from a position facing the main surface 20 of the substrate 1, the liquid supply port 7 extends in the longitudinal direction (Y direction) of the substrate 1, and at least a part of the partition wall 19 is the support member 18. Is a non-contact portion 19a which is a portion that does not abut. FIG. 3 shows an example in which the entire partition wall 19 is a non-contact portion 19a. Therefore, in FIG. 3, this communication between the liquid supply ports occurs in the longitudinal direction (Y direction) of the substrate 1.

A gap 2 is formed between the non-contact portion 19a of the partition wall 19 and the support member 18. Since the liquid can flow in this gap 2, for example, even if a large amount of liquid is discharged from the discharge port communicating with the liquid supply port 7 located at the left end shown in FIG. 3, the liquid located at the center or the right end. The liquid in the supply port 7 flows into the liquid supply port 7 at the left end. As a result, even if a large amount of liquid is consumed only from a specific ejection port, ink is supplied from other liquid supply ports, so that it becomes difficult to supply the liquid at an early stage only to the specific ejection port. It can be suppressed. Then, as shown in FIG. 3B, when the cross section of the liquid supply port 7 in the lateral direction (X direction) is viewed, the opening width d at any position of the liquid supply port 7 is also the liquid supply port 7. It is less than or equal to the opening width (d1 or less) on the support member side of. Since the liquid supply port 7 has a shape satisfying such a condition, the substrate 1 can have a larger portion remaining than the substrate 1 shown in FIG. 9 of the comparative example, and the rigidity of the substrate 1 can be obtained. Will be able to be secured. Therefore, the deformation of the recording element substrate 15 can be suppressed.

Next, a method of manufacturing the recording element substrate 15 of the present embodiment will be described with reference to FIG. FIG. 4 is a schematic view showing each step of the manufacturing method of the recording element substrate 15, and shows the cross section of AA'shown in FIG. 3 in each step. First, as shown in FIG. 4A, the substrate 1 is a silicon single crystal substrate in which the adhesion improving layer 3 and the flow path forming member 10 are formed on the front surface, and the polyether amide resin which is the mask layer 9 is formed on the back surface. I prepared. At this time, regarding the dimensions of the opening of the liquid supply port 7 of the mask layer 9, the dimension of the substrate 1 in the lateral direction (X direction) was 750 um, and the dimension in the longitudinal direction (Y direction) was 9000 um. The longitudinal dimension of the non-contact portion was 400 um, and the longitudinal dimension of the contact portion was 600 um. As shown in FIG. 4A, the mask layer 9 is not formed between the adjacent liquid supply ports for the non-contact portion that allows the adjacent liquid supply ports to communicate with each other in the lateral direction.

Next, as shown in FIG. 4B, the discharge port forming member 4 was formed on the flow path forming member 10 with a cationically polymerized epoxy resin. Then, in order to form the liquid supply port, the non-penetrating hole 11 was formed in the substrate 1 by using the laser beam of the triple wave (THG: wavelength 355 nm) of the YAG laser.

Next, as shown in FIG. 4C, anisotropic etching is performed from the back surface of the substrate 1. TMAH (tetramethylammonium hydroxide) was used as the etching solution used for anisotropic etching, and etching was performed at a solution temperature of 80 ° C. and an etching time of 8.5 hr. By this etching, a liquid supply port 7 in which the liquid supply ports 7 communicate with each other was formed. The etching liquid enters the inside of the plurality of non-penetrating holes 11 formed on the back surface side of the substrate 1, and the etching proceeds, so that the opening in which the etching mask layer 9 is not formed and the adjacent liquid supply port 7 Part of the partition is etched. As the etching progresses on the surface of the substrate, the inside of the liquid supply port 7 also expands in the lateral direction to obtain a desired opening.

Next, as shown in FIG. 4D, the mask layer 9 on the back surface of the substrate 1 and the flow path forming member 10 on the surface of the substrate 1 were removed. Finally, the substrate 1 is cut and separated by dicing or the like to form the recording element substrate 15, and the recording element substrate 15 is joined to the electric wiring connection and the support member 18 to complete the liquid discharge head 16.

(Second embodiment)
The second embodiment will be described with reference to FIG. The same parts as those in the first embodiment are designated by the same reference numerals, and the description thereof will be omitted. FIG. 5 shows the recording element substrate 15 in this embodiment. FIG. 5A is a plan view seen from the back surface side of the substrate 1. 5 (b) is a cross-sectional view taken along the line AA'shown in FIG. 5 (a). 5 (c) is a cross-sectional view taken along the line BB'shown in FIG. 5 (a). In the present embodiment, as shown in FIG. 5, the partition wall 19 has a non-contact portion 19a that does not abut on the support member 18 and a contact portion 19b that abuts on the support member 18. That is, in the present embodiment, only a part of the partition wall 19 is a non-contact portion 19a.

Since the partition wall 19 has an abutting portion 19b that abuts on the support member 18, the support member 18 and the substrate 1 are joined by an adhesive in the abutting portion 19b, and the strength of the substrate 1 can be ensured. As a result, deformation of the recording element substrate 15 can be suppressed. Furthermore, since the contact portion 19b is formed, more of the substrate 1 can be left, so that the rigidity of the substrate 1 can be maintained. Therefore, according to the present embodiment, the liquid flows through the gap 2 between the non-contact portion 19a and the support member 18, so that the strength of the substrate is further increased while suppressing the bias of the liquid consumption between the liquid supply ports. Can be secured.

Further, in the lateral direction (X direction) of the substrate 1, the opening width of the central portion of the liquid supply port 7 formed at a position adjacent to the non-contact portion 19a in the substrate thickness direction is b. Then, let a be the opening width of the central portion of the liquid supply port 7 formed at a position adjacent to the contact portion 19b in the substrate thickness direction. In this case, it is preferable to form the liquid supply port 7 so that the relationship is a <b. Since the gap 2 with the non-contact portion 19a support member 18 is a minute space, the resistance of the fluid is larger than that of the liquid supply port 7. Therefore, it may be difficult to smoothly supply the liquid from another liquid supply port to the liquid supply port 7 which consumes a large amount of liquid. Therefore, as shown in FIGS. 5 (b) and 5 (c), it is preferable that the liquid supply port of the portion adjacent to the gap 2 is formed so as to satisfy the above-mentioned relationship of a <b. As a result, the liquid can flow more smoothly between the liquid supply ports.

(Third embodiment)
The third embodiment will be described with reference to FIGS. 6 and 7. FIG. 6 is a schematic view showing the recording element substrate 15 in the present embodiment, and FIG. 6A is a plan view corresponding to FIG. 3A. FIG. 6B is a cross-sectional view taken along the line AA'shown in FIG. 6A. FIG. 6 (c) is a cross-sectional view taken along the line BB'shown in FIG. 6 (a). In the present embodiment, the contact portion 19b of the partition wall 19 is formed in the central portion having the lowest rigidity in the longitudinal direction (Y direction) of the substrate 1. Thereby, the strength of the substrate 1 can be further secured. Here, the central portion of the partition wall 19 is a region surrounded by a circle having a radius d / 5 (d is the total length in the longitudinal direction of the partition wall 19) around the center of gravity in the longitudinal direction (Y direction) of the partition wall 19. To say. In this embodiment as well, as in the second embodiment, it is more preferable that the opening width of the liquid supply port satisfies the relationship of a <b.

FIG. 7 is a modification of the recording element substrate 15 in the present embodiment, and FIG. 7A is a plan view corresponding to FIG. 6A. 7 (b) is a cross-sectional view taken along the line AA'shown in FIG. 7 (a). 7 (c) is a cross-sectional view taken along the line BB'shown in FIG. 7 (a). In the recording element substrate 15 shown in FIG. 7, it is recorded in FIG. 6 that not only the contact portion 19b of the partition wall 19 is provided at the central portion in the longitudinal direction (Y direction) but also the abutting portion 19b is formed at the end portion. This is different from the element substrate 15. Here, the end portion of the partition wall 19 refers to a region from the end of the partition wall 19 in the longitudinal direction (Y direction) to d / 5 (d is the total length of the partition wall 19 in the longitudinal direction).

From the viewpoint of increasing the strength of the partition wall 19, it is preferable that the contact portion 19b is formed at the central portion in the longitudinal direction of the partition wall 19. Then, by forming the contact portion 19b not only in the central portion but also in the end portion in the longitudinal direction of the partition wall 19, the strength of the partition wall 19 can be further secured.

Further, in the second embodiment and the third embodiment, the non-contact portion 19a is arranged in the lateral direction (X direction) of the substrate 1 when viewed from the position facing the main surface 20 of the substrate 1. However, the second embodiment and the third embodiment are not limited to this. That is, the non-contact portion 19a and the contact portion 19b may be formed side by side in the lateral direction. Further, the non-contact portion 19a and the contact portion 19b may be arranged in a staggered manner when viewed from a position facing the main surface 20 of the substrate 1. Due to the staggered arrangement, the rigidity of the recording element substrate 15 is kept uniform regardless of the location. As a result, there are no more places where the rigidity is locally low. Therefore, for example, even if a force is applied to the recording element substrate 15 from any direction, it is possible to suppress the deformation of the recording element substrate 15. ..

1 Board 2 Gap 4 Discharge port forming member 5 Discharge port 7 Liquid supply port 18 Support member 19 Partition wall 19a Non-contact part 20 Main surface of the board

Claims (12)

A discharge port forming member that forms a discharge port that discharges liquid,
A substrate having a plurality of liquid supply ports for supplying liquid to the discharge port of the discharge port forming member, and a partition wall formed between the plurality of liquid supply ports.
A support member that supports the substrate and
In a liquid discharge head equipped with
When viewed from a position facing the main surface of the substrate, the liquid supply port extends along the longitudinal direction of the substrate.
When viewed from a position facing the main surface of the substrate, the plurality of liquid supply ports are arranged along the lateral direction of the substrate.
At least a part of the partition wall is a non-contact portion that does not abut on the support member.
Of the plurality of liquid supply ports, the liquid supply ports formed adjacent to each other communicate with each other by a gap between the non-contact portion and the support member.
When the cross section of the liquid supply port in the lateral direction is viewed, the opening width at any of the liquid supply ports is equal to or less than the opening width of the liquid supply port on the support member side. head. The liquid discharge head according to claim 1, wherein the partition wall further has a contact portion that comes into contact with the support member. The liquid discharge head according to claim 2, wherein the contact portion is joined to the support member by an adhesive. The liquid discharge head according to claim 1, wherein the entire partition wall is the non-contact portion. The liquid discharge head according to claim 2 or 3, wherein only a part of the partition wall is the non-contact portion. Of the liquid supply ports extending along the longitudinal direction, the opening width of the central portion in the substrate thickness direction of the portion adjacent to the abutting portion in the lateral direction is a, the non-contact portion and the non-contact portion. The liquid discharge head according to claim 2 or 3, wherein a <b is satisfied when the opening width of the central portion in the substrate thickness direction of the portion adjacent to the lateral direction is b. The liquid discharge head according to any one of claims 1 to 5, wherein a plurality of non-contact portions are formed side by side in the lateral direction when viewed from a position facing the main surface of the substrate. The liquid discharge head according to claim 2 or 3, wherein the non-contact portion and the contact portion are formed side by side in the lateral direction when viewed from a position facing the main surface of the substrate. The liquid discharge head according to claim 2 or 3, wherein the contact portions are formed in a staggered manner when viewed from a position facing the main surface of the substrate. The liquid discharge head according to claim 2 or 3, wherein the contact portion is formed in a central portion of the partition wall. The liquid discharge head according to claim 10, wherein the contact portion is also formed at an end portion of the partition wall. The liquid discharge head according to any one of claims 1 to 11, wherein the substrate is a silicon substrate.

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