WO2015080265A1

WO2015080265A1 - Liquid discharge head

Info

Publication number: WO2015080265A1
Application number: PCT/JP2014/081624
Authority: WO
Inventors: 純丸林; 勝哉深谷; 光高松
Original assignee: コニカミノルタ株式会社
Priority date: 2013-11-29
Filing date: 2014-11-28
Publication date: 2015-06-04
Also published as: JP6439700B2; JPWO2015080265A1

Abstract

The purpose of the present invention is to provide a liquid discharge head in which adhesive-agent-capturing grooves of a size sufficiently large to capture surplus adhesive agent can be formed in a nozzle plate, even if nozzle density is high. Accordingly, a droplet discharge head is provided with: a head tip provided with a plurality of pressure chambers (12); and a nozzle plate (20) which is adhered to the head tip, and which is provided with nozzles (21) for discharging droplets. Openings (121) of the pressure chambers (12) are provided in a surface to be adhered to the nozzle plate (20). Adhesive-agent-capturing grooves (30) are formed in a nozzle-plate (20) surface to be adhered to the head tip, said grooves being formed in areas of said surface which overlap the openings (121) of the pressure chambers (12), and which do not overlap the nozzles (21).

Description

Liquid discharge head

The present invention relates to a liquid discharge head, and more particularly, to a liquid discharge head capable of forming an adhesive capturing groove having a size sufficient to capture excess adhesive even in a nozzle with a high density.

A liquid discharge head formed by adhering a nozzle plate having nozzles for discharging liquid to the end surface of the head chip using an adhesive is used when the nozzle plate is applied to the head chip as the nozzle density increases. It has been a problem that the low-viscosity adhesive before curing protrudes from the sticking surface and flows into the pressure chamber.

FIG. 19 is a cross-sectional view showing one pressure chamber 501 of a conventional droplet discharge head, in which 500 is a head chip, and 600 is a nozzle plate. The adhesive applied to the end surface 500a of the head chip 500 overflows and flows into the pressure chamber 501 when the nozzle plate 600 is adhered, and intersects with the inner wall surface of the pressure chamber 501 as shown in the figure. An adhesive fillet F is formed over the nozzle plate 600. As the adhesive fillet F is cured, the pressure chamber 501 is completely sealed with the nozzle plate 600.

However, if a large amount of excess adhesive flows into the pressure chamber 501, the adhesive fillet F formed between the head chip 500 and the nozzle plate 600 further increases, and the volume in the pressure chamber 501 is greatly reduced. There is a risk of letting you. In particular, in a droplet discharge head of a type that generates pressure by deforming the

walls

502 and 502 constituting the pressure chamber 501, if the adhesive fillet F enters deep into the pressure chamber 501, this wall There is a possibility that the deformation operation of 502 and 502 may be hindered and a predetermined pressure cannot be generated in the pressure chamber 501.

Further, when the adhesive fillet F is further increased in size, the end thereof reaches the nozzle 601 and may flow into the nozzle 601 to cause nozzle clogging.

Such a problem is affected by the fact that the density of the pressure chamber provided in the head chip increases as the nozzle density increases, and the opening width of the pressure chamber on the nozzle plate side becomes narrower. In addition, as the number of pressure chambers increases, the size of the head chip increases, making it difficult to uniformly apply the adhesive to the whole, and a portion where the amount of application increases partially tends to occur. It is thought that this also has an effect.

Conventionally, in order to prevent such an adhesive from flowing in, a small hole for capturing excess adhesive when attached to the head chip, in the vicinity of the nozzle of the nozzle plate of the part to be attached to the end face of the head chip It has been proposed to form a groove (Patent Document 1). This groove is smaller than the nozzle diameter and is formed in the vicinity of the nozzle.

JP-A-7-117230

As the inventors examined, as the density of the nozzle progresses, even if a groove for capturing excess adhesive is formed in the vicinity of the nozzle of the nozzle plate of the part to be attached to the end face of the head chip, It turned out that it was not able to respond enough.

That is, as the nozzle density is increased, the pressure chambers are increased in density, and the interval between adjacent pressure chambers corresponding to the end face of the head chip to which the nozzle plate is attached is also narrowed. For this reason, it is difficult to form a groove in the part of the nozzle plate corresponding to this end face, and it is necessary to form a groove with a very small diameter, and the excess adhesive is sufficiently captured. There was a problem that the adhesive that could not be caught and flowed into the pressure chamber flowed.

Therefore, the present invention has an object to provide a liquid discharge head capable of forming an adhesive capturing groove having a size large enough to capture excess adhesive even in a nozzle with a high density. And

Other problems of the present invention will become apparent from the following description.

The above problems are solved by the following inventions.

1. A head chip having a plurality of pressure chambers, and a nozzle plate having nozzles attached to the head chips and ejecting droplets, and an opening of the pressure chamber is disposed on an attachment surface with the nozzle plate. In the liquid drop ejection head,
A droplet discharge head in which an adhesive catching groove is formed in a portion of the nozzle plate that is attached to the head chip and covers the opening of the pressure chamber and does not reach the nozzle.

2. The pressure chamber is constituted by a channel formed in a groove shape,
The head chip has a configuration in which a partition between adjacent channels in a channel row configured by a plurality of the channels includes a piezoelectric material, and pressure is generated in the channel by deformation of the partition.
2. The droplet discharge head according to 1, wherein the adhesive capturing groove is formed so as to straddle at least a part of a peripheral edge of the opening of the channel.

3. The pressure chamber is constituted by a channel formed in a groove shape,
The head chip has a configuration in which a partition between adjacent channels in a channel row configured by a plurality of the channels includes a piezoelectric material, and pressure is generated in the channel by deformation of the partition, and The channels in the channel row are configured by alternately arranging drive channels that discharge droplets and dummy channels that do not discharge droplets.
The nozzle plate, the nozzle is not formed in a portion corresponding to the dummy channel,
2. The liquid droplet ejection head as described in 1, wherein the adhesive capturing groove is formed in a portion over the opening of the dummy channel.

4). The pressure chamber is constituted by a channel formed in a groove shape,
The head chip has a configuration in which a partition between adjacent channels in a channel row configured by a plurality of the channels includes a piezoelectric material, and pressure is generated in the channel by deformation of the partition, and The channels in the channel row are configured by alternately arranging drive channels that discharge droplets and dummy channels that do not discharge droplets.
The nozzle plate, the nozzle is not formed in a portion corresponding to the dummy channel,
The adhesive catching groove is formed in a portion that covers the opening of the drive channel and is formed in a portion that covers the opening of the dummy channel and the first adhesive catching groove formed in a portion that does not cover the nozzle. 2. The liquid droplet ejection head as described in 1 above, further comprising a second adhesive capturing groove.

5. 5. The liquid droplet ejection head according to any one of 1 to 4, wherein the nozzle plate is made of resin.

6. 6. The droplet discharge head according to 5, wherein the nozzle plate is polyimide.

The perspective view which cuts and shows an example of a liquid discharge head Partial front view of the liquid ejection head shown in FIG. Sectional view along line (iii)-(iii) in FIG. The figure which expands and shows the adhesive agent acquisition groove | channel of the upper side in FIG. (A) (b) is a figure explaining the other arrangement | positioning aspect of an adhesive agent capture groove | channel. 5A is an enlarged view showing the upper adhesive catching groove in FIG. 5A, and FIG. 5B is an enlarged view showing the upper adhesive catching groove in FIG. 5B. (A) (b) is a figure explaining the other arrangement | positioning aspect of an adhesive agent capture groove | channel. (A) (b) is a figure explaining the other arrangement | positioning aspect of an adhesive agent capture groove | channel. (A) (b) is a figure explaining the other arrangement | positioning aspect of an adhesive agent capture groove | channel. (A) (b) is a figure explaining the other arrangement | positioning aspect of an adhesive agent capture groove | channel. (A)-(c) is a figure explaining the other shape of an adhesive agent capture groove | channel. Partial front view showing an example of an independent drive type liquid discharge head Sectional view along line (xiii)-(xiii) in FIG. (A) (b) is a figure explaining the other arrangement | positioning aspect of the adhesive agent capture groove | channel corresponding to a dummy channel. (A) (b) is a figure explaining the other shape of the adhesive agent capture groove | channel corresponding to a dummy channel. The figure explaining an example which has arrange | positioned the adhesive capture groove | channel to the drive channel and dummy channel of an independent drive type liquid discharge head, respectively Sectional drawing which shows another example of a droplet discharge head The partial bottom view which looked at the droplet discharge head shown in FIG. 17 from the nozzle side Sectional drawing which shows one pressure chamber of the conventional droplet discharge head

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

FIG. 1 is a perspective view showing an example of a liquid discharge head according to the present invention by cutting.

In the droplet discharge head 1A, 10 is a head chip, and 20 is a nozzle plate adhered to the end surface 10a of the head chip 10 with an adhesive.

The head chip 10 is a component in which a pressure chamber is formed in the present invention, and a plurality of narrow grooves 12 which are pressure chambers are arranged in parallel on a channel substrate 11. A partition 13 functioning as a pressure applying unit is provided between the

adjacent channels

12 and 12. One partition wall 13 is shared by

adjacent channels

12 and 12. Therefore, the channel substrate 11 constitutes one channel row by arranging the channels 12 and the partition walls 13 in an alternating manner. A cover substrate 14 is provided on the upper surface of the channel substrate 11 so as to block all the channels 12 above.

One end of each channel 12 opens to the end surface 10a of the head chip 10 that is a bonding surface with the nozzle plate 20 to form an opening 121, and the other end gradually becomes a shallow groove as the distance from the nozzle plate 20 increases. The cover substrate 14 communicates with a common channel hole 15 formed in the opening. The common flow path hole 15 is opened in common to each channel 12, and supplies ink that is sent via an ink supply pipe (not shown) to each channel 12.

The nozzle plate 20 is a component that is attached to the end face 10a of the head chip 10 so as to close the opening of the pressure chamber (the opening 121 of the channel 12) in the present invention. The nozzle 21 is formed so as to be disposed in the opening 121.

In the present invention, the nozzle refers to the entire flow path that penetrates the nozzle plate and communicates the inside of the pressure chamber with the outside.

Each partition wall 13 is formed including a piezoelectric material such as PZT that functions as an electromechanical conversion means. The piezoelectric material may be part of the partition wall 13 or the entire partition wall 13 may be formed of a piezoelectric material. Drive electrodes (not shown) are formed on the wall surfaces of both partition walls 13 facing the inner surface of each channel 12. When a drive signal having a predetermined voltage is applied to each of the drive electrodes provided so as to sandwich the partition wall 13, the partition wall 13 is deformed to the outside or the inside according to the drive signal. Due to the deformation of the partition wall 13, a pressure wave is generated in the channel 12, and a pressure for ejecting from the nozzle 21 is applied to the ink supplied in the channel 12.

In this liquid ejection head 1A, an adhesive capturing groove 30 for capturing excess adhesive when the nozzle plate 20 is adhered to the adhesive surface 20a of the head chip 10 with the end surface 10a of the head chip 10 in this liquid ejection head 1A. Are formed independently for each channel.

The adhesive capturing groove 30 will be further described with reference to FIGS. FIG. 2 is a partial front view of the droplet discharge head 1A shown in FIG. 1 as viewed from the nozzle plate 20 side, and shows only two

adjacent channels

12 and 12. FIG. 3 is a cross-sectional view taken along line (iii)-(iii) in FIG. In FIG. 2, the adhesive capturing groove 30 is indicated by oblique lines. In FIG. 3, the adhesive between the head chip 10 and the nozzle plate 20 is not shown.

The adhesive capturing groove 30 is a concave groove that is recessed from the sticking surface 20a of the nozzle plate 20, and has a horizontally long rectangular shape when viewed from the front when the nozzle plate 20 is observed from the direction opposite to the droplet discharge direction. It is formed as follows. Each adhesive capturing groove 30 extends from the end face 10a of the head chip 10 to the opening 121 across the peripheral edge 122 of the opening 121 of the channel 12 and does not cover the opening 211 on the inlet side of the nozzle 21. Has been placed. That is, each of the adhesive capturing grooves 30 is located on the whole of the

edge portions

122a and 122c positioned up and down in the drawing among the four straight edges 122a to 122d of the peripheral edge 122 of the opening 121 and on the left and right in the drawing. It arrange | positions so that the both ends of the

edge parts

122b and 122d to perform may be straddled. For this reason, each adhesive capturing groove 30 overlaps with a part of the opening 121 of the channel 12, but does not overlap with the opening 211 on the inlet side of the nozzle 21. In addition, the inside of each adhesive capturing groove 30 communicates with the inside of the channel 12.

As a result, when the nozzle plate 20 is adhered to the end surface 10a of the head chip 10 to which the adhesive has been applied, excess adhesive flows between the head chip 10 and the nozzle plate 20 toward the channel 12. A part of the adhesive can be captured in the adhesive capturing groove 30 before the channel 12, and a large amount of adhesive can be prevented from flowing into the channel 12.

The adhesive capturing groove 30 extends not only from the end surface 10a of the head chip 10 to which the nozzle plate 20 is adhered, but also from the end surface 10a to the opening 121 across the peripheral edge 122 of the opening 121 of the channel 12. Since it is formed, it is possible to ensure a large volume compared to the case where it is formed only in the portion corresponding to the end face 10a of the head chip 10 between the

adjacent channels

12 and 12 as in the prior art. For this reason, even if the density is increased and the distance between the

adjacent channels

12 and 12 is narrowed, it is possible to form the adhesive capturing groove 30 having a sufficient volume for capturing excess adhesive.

In particular, as shown in the present embodiment, a liquid droplet ejection head of a type that generates a pressure for ejecting liquid droplets into the channel 12 by deforming the partition wall 13 between the

adjacent channels

12 and 12 includes a partition wall 13. If a large amount of adhesive adheres to the surface of the film and hardens, not only the volume of the channel 12 is reduced by the cured adhesive, but also the deformation operation of the partition wall 13 is hindered, and the ink in the channel 12 is lost. There is also a possibility that a predetermined pressure cannot be applied. However, since the adhesive capturing groove 30 is formed so as to extend from the end surface 10a of the head chip 10 to the opening portion 121 across the peripheral edge 122 of the opening portion 121 of the channel 12, it can be formed with a larger volume than before. And the excess adhesive flowing toward the channel 12 can be sufficiently captured.

This will be further described with reference to FIG. FIG. 4 is an enlarged view of the upper adhesive capturing groove 30 in FIG. When the adhesive G between the end face 10 a of the head chip 10 and the nozzle plate 20 flows toward the channel 12, it is captured in the adhesive capturing groove 30 before the channel 12. Since the adhesive capturing groove 30 can be formed in a larger volume compared to the conventional case, a large amount of the adhesive G can be captured, and the amount of the adhesive flowing into the channel 12 can be reduced accordingly. For this reason, a large-sized adhesive fillet due to a large amount of adhesive is not formed in the channel 12, and the volume of the channel 12 is reduced by such a large amount of adhesive, or a large amount of adhesive is applied to the partition wall 13. It is possible to drastically reduce the risk of curing by adhering to the surface and hindering the deformation operation of the partition wall 13.

In addition, the adhesive capture groove 30 makes it difficult for an adhesive fillet to be formed at a portion where the adhesive capture groove 30 is disposed, and the inner surface of the channel 12 at a portion other than the portion where the adhesive capture groove 30 is disposed. Even if an adhesive fillet is formed from the nozzle plate 20 to the nozzle plate 20, the adhesive is captured in the adhesive capturing groove 30, and the nozzle 21 is difficult to reach because the adhesive is captured. .

The size of the adhesive catching groove 30 may be such that the adhesive catching

grooves

30, 30 arranged corresponding to the

adjacent channels

12, 12 do not communicate with each other. It can be set as appropriate depending on the amount of excess adhesive. For example, the length of the adhesive capturing groove 30 along the channel row direction is not limited to the channel width (the length between the

edge portions

122b and 122d) as illustrated, You may make it not straddle the

edge parts

122b and 122d by forming the same or shorter than it.

Further, the depth of the adhesive capturing groove 30 may be a depth that does not penetrate the nozzle plate 20, and is appropriately determined depending on the size of the adhesive capturing groove 30, the amount of excess adhesive to be captured, and the like. If the depth is too deep, the strength of the nozzle plate 20 is reduced, so that the thickness of the nozzle plate 20 is preferably ½ or less.

The adhesive capturing groove 30 shown in FIGS. 1 to 4 includes the

adjacent channels

12, 12 among the peripheral edge 122 formed by the four straight edges 122 a to 122 d of the rectangular opening 121 of the channel 12. Along the two

edge portions

122a and 122c that are not sandwiched between the end surface 10a of the head chip 10 and the

edge portions

122a and 122c, respectively, and so as not to reach the opening portion 211 on the inlet side of the nozzle 21, The nozzle 21 is formed at a distance from the opening 211 on the inlet side. As a result, two adhesive capturing

grooves

30 and 30 are arranged for one nozzle 21 so as to sandwich the nozzle 21.

However, the adhesive capturing groove 30 only needs to be formed in a portion that extends from the end face 10a of the head chip 10 to the opening 121 of the channel 12 and does not cover the opening 211 on the inlet side of the nozzle 21, It is not limited to the above arrangement mode. The arrangement mode of the adhesive capturing groove 30 depends on various conditions such as the size of the opening 121 of the channel 12, the size of the nozzle 21, the distance between the

adjacent channels

12 and 12, and the amount of excess adhesive to be captured. Various changes can be made accordingly.

Hereinafter, other arrangement modes of the adhesive capturing groove 30 will be described.

5A, the adhesive capturing groove 30 is arranged in the channel row direction of the peripheral edge 122 of the opening 121 of the channel 12 (the left-right direction in FIG. 5A). It extends along the two

edge portions

122a and 122c along the same line, but is arranged at a portion where the

edge portions

122a and 122c do not straddle. The adhesive capturing groove 30 is located at a position where the groove edge 30a far from the nozzle 21 overlaps the

edges

122a and 122c of the opening 121 of the channel 12, and spreads to the nozzle 21 side from these

edges

122a and 122c. The nozzles 21 are arranged so as not to cover the nozzles 21.

Thus, even if the adhesive capturing groove 30 is disposed so as not to straddle the

edges

122a and 122c of the peripheral edge 122 of the opening 121 of the channel 12, as shown in FIG. The excess adhesive G flowing from the end face 10a toward the nozzle 21 can be captured, and the occurrence of nozzle clogging can be reduced.

Moreover, the arrangement | positioning aspect of the adhesive agent capture groove | channel 30 shown in FIG.5 (b) is two

edge part

122a, 122c along the channel row | line | column direction among the peripheral edges 122 of the opening part 121 of the channel 12 in the adhesive agent capture groove | channel 30. Are arranged between the

edge portions

122a and 122c and the nozzle 21.

In this way, even if the adhesive capturing groove 30 is disposed between the

edges

122a and 122c and the nozzle 21 without straddling the

edges

122a and 122c of the opening 121 of the channel 12, as shown in FIG. As shown, surplus adhesive G flowing toward the nozzle 21 from the end surface 10a of the head chip 10 through the sticking surface 20a of the nozzle plate 20 can be captured, and the occurrence of nozzle clogging can be reduced.

In general, the channel 12 has a height direction (vertical direction in FIGS. 5A and 5B) larger than a width direction (horizontal direction in FIGS. 5A and 5B). As shown in FIGS. 5 (a) and 5 (b), the groove 30 is disposed between the

edge portions

122a and 122c and the nozzle 21, so that a large volume can be obtained even when the interval between the

adjacent channels

12 and 12 is reduced. Can be secured.

The adhesive capturing grooves 30 shown in FIGS. 5 (a) and 5 (b) are also not shown in the figure, but the edge 122b is formed to be the same as or shorter than the channel width. , 122d may not be straddled.

The arrangement mode of the adhesive capturing groove 30 shown in FIG. 7A intersects the channel row direction (the left-right direction in FIG. 7A) of the peripheral edge 122 of the rectangular opening 121 of the channel 12. Are formed in a vertically long rectangular shape so as to straddle the

edge portions

122b and 122d from the end face 10a of the head chip 10 along the two

edge portions

122b and 122d.

Thus, even if the adhesive capturing grooves 30 are arranged between the

adjacent channels

12 and 12, each adhesive capturing groove 30 is arranged so as to extend from the end face 10 a of the head chip 10 to the opening 121 of the channel 12. Therefore, a larger volume than the conventional one can be secured, and the same effect as described above can be obtained.

Although the adhesive capturing groove 30 shown in FIG. 7A is also not shown in the drawing, the length along the

edges

122b and 122d is the same as or shorter than the

edges

122b and 122d. You may make it not straddle 122a and 122c.

In addition, when there is a margin in the channel width, the adhesive capturing groove 30 arranged so as to extend in the direction along the

edge portions

122b and 122d does not straddle the

edge portions

122b and 122d as shown in FIG. a) Similarly to (b), the groove edge 30b far from the nozzle 21 overlaps with the

edges

122a and 122c of the opening 121 of the channel 12, or is closer to the nozzle 21 than the

edges

122a and 122c. You may arrange | position so that it may become a position.

7 (b) is an arrangement in which only one adhesive catching groove 30 shown in FIG. 2 is placed for one nozzle 21. The adhesive catching groove 30 shown in FIG. In this case, in the

adjacent channels

12 and 12, as shown in the figure, the edges that the adhesive capturing groove 30 straddles are arranged on the peripheral edge 122 so that the edges that the adhesive capturing groove 30 straddles are not arranged on the same side. It is preferable to make the edge 122a and the edge 122c opposite to each other different. According to this, since the adhesive capturing

grooves

30 and 30 corresponding to the

adjacent channels

12 and 12 do not interfere with each other, the length of the adhesive capturing groove 30 (the length in the left-right direction in the figure) is as much as possible. Can be formed longer and the volume can be further increased.

Moreover, like the arrangement | positioning aspect demonstrated in FIG. 2, you may form the length of the adhesive capture | acquisition groove | channel 30 so that it may not straddle the

edge parts

122b and 122d, and is the same as FIG. 5 (a) (b). The groove edge 30a on the side farther from the nozzle 21 of the adhesive capturing groove 30 may be positioned so as to overlap with the

edges

122a and 122c or be positioned closer to the nozzle 21 than the

edges

122a and 122c. Of course it is good.

8A is an arrangement in which only one adhesive catching groove 30 shown in FIG. 7A is arranged for one nozzle 21. The adhesive catching groove 30 shown in FIG. That is, the adhesive capturing groove 30 is arranged along the

edge

122 b or 122 d of the opening 121 of the channel 12.

As shown in the drawing, when the adhesive capturing groove 30 is disposed so as to straddle the

edge

122b or 122d, it is preferable that the two adhesive capturing grooves 30 are not disposed between the

adjacent channels

12 and 12 together. . By doing so, even if the density is further increased and the distance between the

channels

12 and 12 is narrowed, the adhesive capturing groove 30 as large as possible can be arranged, and the volume can be further increased. be able to.

The arrangement mode of the adhesive capturing groove 30 shown in FIG. 8B is one in which one adhesive capturing groove 30 bent in an L shape with respect to one nozzle 21 is disposed.

Here, the left adhesive catching groove 30 is arranged so as to straddle the

edges

122a and 122b, and the end thereof is placed so as to straddle the

edges

122c and 122d, and the right adhesive catching groove 30 is formed of the edge 122b. , 122c, and the ends thereof are arranged so as to straddle the

edges

122a, 122d. As a result, the straight portions of the adhesive capturing

grooves

30 and 30 are not arranged together at the

edges

122b and 122d between the

adjacent channels

12 and 12, and the

edges

122a and 122a of the

adjacent channels

12 and 12 are connected to each other. Alternatively, the straight portions of the adhesive capturing

grooves

30 and 30 are not arranged between the

edges

122c and 122c. By doing in this way, even if the space | interval between the

channels

12 and 12 becomes narrow, the adhesive capture groove | channel 30 as large as possible can be arrange | positioned, and since it can attain a larger volume, it is preferable.

Although not shown in the figure, each adhesive capturing groove 30 shown in FIG. 8B has four edges 122a to 122d formed by preventing the end from straddling the

edges

122c, 122d or 122a, 122d. It may be arranged so as to cover only two adjacent edges, and either one or both of the two

groove edges

30a, 30b on the side far from the nozzle 21 are on the end face 10a of the head chip 10. In order not to be applied, it may be arranged so as to overlap with the edge portions 122a to 122d, or to be positioned closer to the nozzle 21 than the edge portions 122a to 122d.

9A and 9B, the adhesive capturing groove 30 is arranged in three of the peripheral edges 122 formed by the four edges 122a to 122d of the opening 121 of the channel 12 with respect to one nozzle 21. One adhesive capturing groove 30 is arranged over one edge.

In the case of FIG. 9A, as shown in the drawing, each adhesive capturing groove 30 extends over the

edge portions

122a, 122b, and 122c so as to straddle the

edge portions

122a, 122b, and 122c. It is preferable that the straight line portions of the adhesive capturing

grooves

30 and 30 are not arranged at 122b and 122d. By doing so, even if the density is further increased and the distance between the

channels

The arrangement mode of the adhesive capturing groove 30 shown in FIG. 9B is such that three edges of the peripheral edge 122 composed of the four edges 122a to 122d of the opening 121 of the channel 12 with respect to one nozzle 21. 7 is the same as FIG. 7A in that only one adhesive capturing groove 30 is disposed over the edge 122a, but here, the straight portion of the adhesive capturing groove 30 is not disposed on the

edge

122a or 122c. It is. Here, one adhesive capturing groove 30 is arranged so as to straddle the

edges

122a, 122b, 122d, and the adjacent adhesive capturing groove 30 is extended to the

edges

122b, 122c, 122d. It is arranged to straddle.

Further, although not shown, each adhesive capturing groove 30 shown in FIGS. 9A and 9B is also arranged so as to cover only any three adjacent edges of the four edges 122a to 122d. Alternatively, the three

groove edges

30a, 30a, 30b on the side far from the nozzle 21 may overlap with the edges 122a to 122d so as not to reach the end face 10a of the head chip 10, or the edges 122a to 122d. You may arrange | position so that it may become the position of the nozzle 21 side rather than 122d.

10A, the adhesive capturing groove 30 is arranged at the corner 122e of the peripheral edge 122 of the rectangular opening 121 of the channel 12 so that the rectangular adhesive capturing groove 30 is connected to the corner 122e. It is arranged so as to straddle.

The adhesive capturing groove 30 may be disposed so as to straddle at least one corner portion 122e with respect to one nozzle 21, but here, one nozzle 21 is disposed so as to straddle four corner portions 122e. On the other hand, four adhesive capturing grooves 30 are arranged. Since the adhesive capturing grooves 30 can be arranged in all the corner portions 122e, the amount of adhesive that can be captured can be increased accordingly.

The arrangement mode of the adhesive capturing groove 30 shown in FIG. 10B is that one adhesive capturing groove 30 is disposed along the entire circumference of the peripheral edge 122 of the opening 121 of the channel 12 with respect to one nozzle 21. It is a thing. That is, one nozzle 21 is completely surrounded by one rectangular adhesive capturing groove 30. Here, the adhesive capturing groove 30 is disposed so as to straddle the entire peripheral edge 122 from the end surface 10a of the head chip 10.

In this embodiment, the adhesive capturing groove 30 can be formed to the largest size, and any direction of excess adhesive flowing into the channel 12 can be captured by the adhesive capturing groove 30. The effect of suppressing the inflow of adhesive into the inside and the effect of suppressing nozzle clogging are the highest.

The adhesive capturing groove 30 arranged so as to surround the nozzle 21 in this way is not shown, but any one or two or

more groove edges

30a, 30b on the side far from the nozzle 21 are formed on the head chip 10. You may arrange | position so that it may become a position which overlaps with the edge parts 122a-122d, or the position of the nozzle 21 side rather than these edge parts 122a-122d so that it may not cover the end surface 10a.

In addition, two or more types of arrangement modes of the adhesive capturing groove 30 described above may be mixed in one droplet discharge head 1A.

The shape of the adhesive capturing groove 30 is not limited to the shape exemplified above, and can be various shapes. For example, in addition to the circular shape in front view shown in FIG. 11 (a) and the elliptical shape in front view shown in FIG. 11 (b), it can be formed to have a triangular shape in front view shown in FIG. 11 (c). In addition, although not shown, it can be formed to have a polygonal shape when viewed from the front.

In the droplet discharge head 1A described above, the channels 12 are all channels that discharge droplets, and the nozzles 21 are formed corresponding to the channels 12 respectively. In the case where the two

adjacent channels

12 and 12 share one partition wall 13 like the droplet discharge head 1A, the droplets cannot be discharged from the two

adjacent channels

12 and 12 at the same time. It is also known to divide each channel that constitutes the liquid crystal into a drive channel that discharges droplets and a dummy channel that does not discharge droplets, and an independent drive type droplet discharge head in which these channels are arranged alternately ing.

Also in such an independent drive type droplet discharge head, the adhesive capturing groove 30 can be disposed at the nozzle plate portion corresponding to the drive channel as described above.

Also, as will be described below, an adhesive capturing groove can be disposed at a site corresponding to the dummy channel.

FIG. 12 is a partial front view showing an example of an independent drive type droplet discharge head 1B, and FIG. 13 is a cross-sectional view taken along line (xiii)-(xiii) in FIG. Since the parts having the same reference numerals as those of the liquid droplet ejection head 1A described above indicate the parts having the same configuration, the detailed description thereof uses the above description and is omitted here. In FIG. 12, the adhesive capturing grooves are indicated by oblique lines. In FIG. 13, the adhesive between the head chip 10 and the nozzle plate 20 is not shown.

In the channel row of the droplet discharge head 1B, drive channels 16 and dummy channels 17 are alternately arranged. The drive channel 16 is a channel for discharging droplets in the same manner as the channel 12 of the droplet discharge head 1A described above. A nozzle 21 is formed at a portion of the nozzle plate 20 corresponding to the opening 161 of the drive channel 16. Since one dummy channel 17 is a channel that does not discharge droplets, the opening 171 is closed by the nozzle plate 20 and no nozzle is formed.

The liquid discharge head 1B has an adhesive for capturing excess adhesive when the nozzle plate 20 is attached to a portion corresponding to the opening 171 of the dummy channel 17 of the attachment surface 20a of the nozzle plate 20. A capture groove 40 is formed independently for each dummy channel 17.

The adhesive catching groove 40 is formed by a rectangular groove that is recessed from the sticking surface 20a of the nozzle plate 20 in the same manner as the adhesive catching groove 30 described above. Here, it is formed in a rectangular shape having an opening area slightly smaller than the opening area of the opening 171 of the dummy channel 17 in front view. Each of the adhesive capturing grooves 40 is disposed at a portion that covers the opening 171 of the dummy channel 17 but does not cover the nozzle 21.

Thereby, when the nozzle plate 20 is stuck to the end surface 10a of the head chip 10 to which the adhesive is applied, the excess adhesion flows between the head chip 10 and the nozzle plate 20 and flows toward the dummy channel 17. The agent is captured in the adhesive capturing groove 40. For this reason, it is possible to suppress a large amount of adhesive from flowing into the dummy channel 17. Although the dummy channel 17 is not a channel for discharging droplets, the

partition walls

13 and 13 on both sides of the dummy channel 17 are shared with the drive channel 16, so that the adhesive is prevented from flowing into the dummy channel 17, so that The possibility of hindering the deformation operation of the

partition walls

13 and 13 can be reduced.

Since the adhesive capturing groove 40 is formed by using the portion of the nozzle plate 20 corresponding to the dummy channel 17 that does not have the nozzle 21, it is not necessary to consider interference with the nozzle 21, so that it has been described above. The volume can be made larger than that of the adhesive capturing groove 30. For this reason, even if the interval between the

adjacent channels

16 and 17 becomes narrow due to the high density, the adhesive capturing groove 40 having a sufficient volume can be formed.

The size of the adhesive capturing groove 40 can be appropriately set according to the distance between the drive channel 16 and the dummy channel 17 and the amount of excess adhesive to be captured. Therefore, as shown in FIG. 14A, the dummy channel 17 may be formed to have the same opening area or shape as the opening area 171 of the opening 171 of the dummy channel 17, and the adjacent drive channel 16. As shown in FIG. 14 (b), each of the

openings

161, 161 is formed so as to have an opening area larger than the opening area of the opening 171 of the dummy channel 17, It is good also as the adhesive capture groove | channel 40 of a large volume by arrange | positioning so that it may protrude from the periphery 172. In FIG. 14B, the adhesive capturing groove 40 is disposed so as to protrude from the entire peripheral edge 172 of the opening 171, but the adhesive capturing groove 40 may be disposed so as to protrude from at least a part of the peripheral edge 172.

Further, the shape of the adhesive capturing groove 40 is not limited to a rectangular shape when viewed from the front, but is circular when viewed from the front as shown in FIG. 15A or elliptical as shown in FIG. It can also be. In addition, although not shown, it may be triangular or other polygonal shapes.

Also, the dummy channel 17 may be formed with an adhesive capturing groove having the same arrangement and shape as the adhesive capturing groove 30 formed in the above-described droplet discharge head 1A.

In such an independent drive type liquid droplet ejection head 1B, in addition to disposing the adhesive capturing groove 40 (second adhesive capturing groove) as described above in the dummy channel 17, an example is shown in FIG. As described above, an adhesive capturing groove 30 (first adhesive capturing groove) similar to that of the above-described droplet discharge head 1A may be disposed in the drive channel 16. According to this, it is possible to prevent the adhesive from flowing into both the drive channel 16 and the dummy channel 17 of the independent drive type droplet discharge head 1B.

Here, the adhesive capturing groove 30 shown in FIG. 7A is arranged in the drive channel 16 in the same manner as the channel 12 of the droplet discharge head 1A, and the adhesive capturing shown in FIG. The groove 40 is illustrated as an example, but the adhesive capturing groove 30 may have other shapes and arrangement modes shown in FIGS. 2, 5, 7 (b) and 8 to 11, The adhesive capturing groove 40 may also have other shapes and arrangement modes shown in FIGS.

In this case, the dummy channel 17 may also be formed with an adhesive capturing groove having the same arrangement and shape as the adhesive capturing groove 30 shown in FIGS. 2 and 5 to 11 described above.

In the present invention, any material that can be used for this kind of nozzle plate material may be used. For example, a synthetic resin such as a polyimide resin, a polyethylene terephthalate resin, a liquid crystal polymer, an aromatic polyamide resin, a polyethylene naphthalate resin, or a polysulfone resin, a metal material such as glass or stainless steel, or silicon can be used.

The nozzle plate may have a single layer structure made of one kind of material, or may have a multilayer structure made of two or more kinds of materials by laminating two or more layers. Among these, resin, glass, and silicon are preferable because they are inexpensive and easy to process the nozzle and the adhesive capturing groove. In particular, those having a single-layer structure made of resin that can easily process nozzles and adhesive capturing grooves by laser processing are preferable, and polyimide resin is more preferable.

Each of the droplet discharge heads 1A and 1B described above has one channel row. However, each of the droplet discharge heads 1A and 1B has a plurality of two or more channel rows. May be. In this case, the adhesive capturing

grooves

30 and 40 can be arranged in each channel row in the same manner as described above.

In the above description, the droplet discharge heads 1A and 1B are exemplified as those that generate a pressure for discharging a droplet into a channel by deforming a partition wall between adjacent channels. The droplet discharge head includes a head chip having a plurality of pressure chambers and a nozzle plate having nozzles attached to the head chip and discharging droplets, and an opening of the pressure chamber is attached to the nozzle plate. What is necessary is just to be arrange | positioned.

Accordingly, the droplet discharge head according to the present invention uses, for example, one wall surface of a pressure chamber as a wall surface that is deformed or vibrated by electromechanical conversion means such as PZT, and ejects droplets from the nozzle into the pressure chamber by deformation or vibration of the wall surface. In addition, a heater may be arranged in the pressure chamber, and droplets may be discharged from the nozzle into the pressure chamber using the liquid film boiling phenomenon caused by energizing the heater. It is also possible to generate a pressure for this purpose.

Of these, FIGS. 17 and 18 show an example of a droplet discharge head in which one wall surface of the pressure chamber is a wall surface vibrated by PZT. FIG. 17 is a cross-sectional view of the droplet discharge head, and FIG. 18 is a partial bottom view of the droplet discharge head as viewed from the nozzle side.

In this

droplet discharge head

1C, 50 is a head chip, 60 is a nozzle plate, and 70 is an ink manifold.

The head chip 50 has a plurality of pressure chambers 51 arranged in parallel. Each pressure chamber 51 constitutes a diaphragm 52 having an upper wall surface formed in a thin plate shape, and a PZT 53 is provided on the upper surface of the diaphragm 52. In addition, the inside of each pressure chamber 51 is connected to the ink flow path 54 opened on the upper surface of the head chip 50, and communicates with the inside of the ink manifold 70 provided on the upper surface of the head chip 50. As a result, the ink stored in the ink manifold 70 is supplied to each pressure chamber 51 in common.

Each pressure chamber 51 is open to the end surface 50a (the lower surface in FIG. 17) of the head chip 50. The nozzle plate 60 is adhered to the end surface 50 a so as to close the opening 511 of the pressure chamber 51 that opens to the end surface 50 a of the head chip 50.

The nozzle plate 60 has a two-layer structure including a first plate 61 disposed on the surface side of the droplet discharge head 1C and a second plate 62 disposed on the side in contact with the end surface 50a of the head chip 50. Yes. The first plate 61 can be formed of silicon, for example. The second plate 62 can be formed of glass, for example.

The nozzle plate 60 is formed with a nozzle 63 that penetrates the first plate 61 and the second plate 62 and communicates the inside of the pressure chamber 51 with the outside of the droplet discharge head 1C. In the droplet discharge head 1 </ b> C, the vibration plate 52 is vibrated by driving the PZT 53, and pressure for discharging from the nozzle 63 is applied to the ink in the pressure chamber 51.

Also in this nozzle plate 60, an adhesive capturing groove 80 is formed in a portion that is applied to the opening 511 of the pressure chamber 51 and that does not cover the nozzle 63, on the bonding surface 60 a with the end surface 50 a of the head chip 50. be able to. As a result, even when the nozzle 63 has a high density, it is possible to form the adhesive capturing groove 80 in the nozzle plate 60 that is large enough to capture excess adhesive.

Here, as shown in FIG. 18, four adhesives are captured in each pressure chamber 51 so as to straddle the peripheral edge 511a of the opening 511 of the pressure chamber 51 from the end surface 50a of the head chip 50 to the pressure chamber 51. A groove 80 is disposed. However, it goes without saying that the adhesive capturing groove 80 of the liquid droplet ejection head 1C can also be arranged in the same manner as the adhesive capturing groove 30 described above.

1A, 1B, 1C: droplet ejection head 10: head chip 10a: end face 11: channel substrate 12: channel 121: opening 122: peripheral edge 122a to 122c: edge 122e: corner 13: partition 14: cover substrate 15 : Common channel hole 16: Drive channel 161: Opening part 17: Dummy channel 171: Opening part 20: Nozzle plate 20 a: Adhering surface with the head chip 21: Nozzle 211: Opening part on the inlet side 30: Adhesive capturing groove (First adhesive capture groove)
30a, 30b: groove edge on the side far from the nozzle 40: adhesive catching groove (second adhesive catching groove)
50: head chip 50a: end face 51: pressure chamber 511: opening 511a: peripheral edge 52: diaphragm 53: PZT
54: Ink channel 60: Nozzle plate 60a: Adhering surface with the head chip 61: First plate 62: Second plate 63: Nozzle 70: Ink manifold 80: Adhesive capturing groove G: Adhesive F: Adhesive fillet

Claims

A head chip having a plurality of pressure chambers, and a nozzle plate having nozzles attached to the head chips and ejecting droplets, and an opening of the pressure chamber is disposed on an attachment surface with the nozzle plate. In the liquid drop ejection head,
A droplet discharge head in which an adhesive catching groove is formed in a portion of the nozzle plate that is attached to the head chip and covers the opening of the pressure chamber and does not reach the nozzle.
The pressure chamber is constituted by a channel formed in a groove shape,
The head chip has a configuration in which a partition between adjacent channels in a channel row configured by a plurality of the channels includes a piezoelectric material, and pressure is generated in the channel by deformation of the partition.
The droplet discharge head according to claim 1, wherein the adhesive capturing groove is formed so as to straddle at least a part of a peripheral edge of the opening of the channel.
The pressure chamber is constituted by a channel formed in a groove shape,
The head chip has a configuration in which a partition between adjacent channels in a channel row configured by a plurality of the channels includes a piezoelectric material, and pressure is generated in the channel by deformation of the partition, and The channels in the channel row are configured by alternately arranging drive channels that discharge droplets and dummy channels that do not discharge droplets.
The nozzle plate, the nozzle is not formed in a portion corresponding to the dummy channel,
The liquid droplet ejection head according to claim 1, wherein the adhesive capturing groove is formed in a portion over the opening of the dummy channel.
The pressure chamber is constituted by a channel formed in a groove shape,
The head chip has a configuration in which a partition between adjacent channels in a channel row configured by a plurality of the channels includes a piezoelectric material, and pressure is generated in the channel by deformation of the partition, and The channels in the channel row are configured by alternately arranging drive channels that discharge droplets and dummy channels that do not discharge droplets.
The nozzle plate, the nozzle is not formed in a portion corresponding to the dummy channel,
The adhesive catching groove is formed in a portion that covers the opening of the drive channel and is formed in a portion that covers the opening of the dummy channel and the first adhesive catching groove formed in a portion that does not cover the nozzle. The droplet discharge head according to claim 1, further comprising a second adhesive capturing groove.
The droplet discharge head according to any one of claims 1 to 4, wherein the nozzle plate is made of resin.
The droplet discharge head according to claim 5, wherein the nozzle plate is made of polyimide.