JP2016221695A - Liquid discharge head and liquid discharge device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid discharge head that has high reliability by suppressing entrainment of an air bubble when a sealing medium is poured in, and a liquid discharge device.SOLUTION: A corner part C of a sealing medium reservoir, into which a sealing medium 7 is to be poured, comprises a member 10 for filling a corner part space Cs of the sealing medium reservoir positioned at the corner part C.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a liquid discharge head and a liquid discharge apparatus capable of discharging a liquid such as ink.

  A liquid discharge apparatus typified by an ink jet recording apparatus has a liquid discharge head. Patent Document 1 describes this type of liquid discharge head. On the support member of the recording head described in Patent Document 1, a recording element substrate and a wiring substrate having an opening in which the recording element substrate fits are bonded and fixed. The electrode of the recording element substrate located in the opening of the wiring board and the lead wire located at the edge of the opening of the wiring board are electrically connected, and a sealing material for sealing those connecting portions is sealed It is poured into the lumber pool.

JP 2006-289720 A

  In the configuration described in Patent Document 1, when the sealing material is poured into the sealing material reservoir, bubbles are likely to be caught in the corners of the sealing material reservoir. When such bubbles are generated, when the sealing material is thermoset, the sealing material is pushed out by the expansion of the bubbles, and the optimal sealing material configuration for electrical insulation is maintained. It may not be possible.

  An object of the present invention is to provide a liquid ejection head and a liquid ejection apparatus with high reliability by suppressing entrainment of bubbles when a sealing material is poured.

  The liquid ejection head of the present invention includes an element substrate provided with an ejection energy generating element for ejecting liquid from an ejection port, a wiring substrate electrically connected to the element substrate, the element substrate, and the wiring substrate. A liquid ejection head comprising: a supporting member for supporting; and a sealing material that seals the element substrate and the wiring substrate with a sealing material reservoir between the element substrate and the wiring substrate. The stop material reservoir includes a corner space located at a corner of the sealant reservoir, and includes a member that at least partially fills the corner space in the corner.

  According to the present invention, by providing a member for filling the corner space of the sealing material reservoir, when the sealing material is poured into the sealing material reservoir, the entrainment of bubbles in the corner space is suppressed, A highly reliable liquid discharge head can be provided.

FIG. 3 is an explanatory diagram of a main part of a recording head according to the first embodiment of the present invention. It is explanatory drawing of the corner | angular part space of the sealing material pool in the 1st Embodiment of this invention. It is explanatory drawing of the corner | angular part space of the sealing material pool as a comparative example. It is explanatory drawing of the corner | angular part space of the sealing material pool in the 2nd Embodiment of this invention. It is explanatory drawing of the corner | angular part space of the sealing material pool in the 3rd Embodiment of this invention. FIG. 2 is an explanatory diagram of a configuration example of a recording apparatus to which the recording head of FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The liquid discharge head in the following embodiments is an application as an inkjet recording head capable of discharging ink as liquid.

(First embodiment)
FIG. 1A is a perspective view of a main part of the ink jet recording head in the present embodiment. In the case of this example, two recording element substrates 2 are disposed on the first support member 1, and these two recording element substrates (element substrates) 2 are disposed on the wiring substrate 4 disposed on the second support member 3. A fitting opening H is formed. FIG. 1B is an enlarged plan view of a connection portion between the recording element substrate 2 and the wiring substrate 4, and FIG. 1C is a cross-sectional view taken along line 1c-1c in FIG. The recording element substrate 2 is formed with an ejection port 2A. Ink is supplied through an ink flow path (not shown), and is ejected from the ejection port 2A by an ejection energy generating element such as an electrothermal conversion element (heater) or a piezoelectric element. Discharged. The first support member 3 is provided with an electrode pad 5 connected to an ejection energy generating element or the like in the recording element substrate 2, and the inner lead 6 of the wiring substrate 4 is connected to the electrode pad 5. . A space between the recording element substrate 2 and the wiring substrate 4 in the opening H is sealed with a lower sealing material 7, and a connection portion between the electrode pad 5 and the inner lead 6 is sealed with an upper sealing material 8. ing. In this example, the planar shape of the opening H is a quadrangle corresponding to the planar shape of the recording element substrate 2 and includes four corners.

  When assembling the components of these recording heads, first, the first support member 1, the recording element substrate 2 and the second support member 3 are bonded, and then the wiring substrate 4 is bonded to the second support member 3. To do. Then, a lower sealing material 7 for insulation protection is poured into a sealing material reservoir formed by the first support member 3, the second support member 3, and the wiring substrate 4, and is thermally cured (thermal cure). ) Thereafter, the upper sealing material 8 is poured into the connection portion between the electrode pad 5 and the inner lead 6, and is thermally cured. The second support member 3 is bonded and fixed to the recording head main body, thereby forming a recording head that can be mounted on the ink jet recording apparatus.

  FIG. 6A is a perspective view for explaining an example of the recording head configured as described above. The wiring board 4 is a flexible wiring board, and is provided with connection pads 9 for exchanging control signals and the like with the recording apparatus main body. Such a recording head can be mounted on the carriage 101 of the serial scan type inkjet recording apparatus 100 as shown in FIG. The carriage 101 is guided by a guide shaft 102 so as to be movable in the main scanning direction indicated by an arrow X, and is moved in the main scanning direction together with the recording head by a moving mechanism including a belt 103 and the like. A recording medium (not shown) stacked on the tray 104 is transported in the sub-scanning direction indicated by an arrow Y that intersects the main scanning direction (orthogonal in this example) by a transport mechanism having transport rollers and the like.

  2A is an enlarged view of a portion IIa in FIG. 1B, and FIG. 2B is a cross-sectional view taken along line IIb-IIb in FIG. 2A. The portion IIa in FIG. 1B corresponds to one of the four corners of the opening H in the wiring board 4 of this example. 4 A of inner peripheral surfaces of the opening part H in the wiring board 4 are projected inside the opening part H rather than the wall surface 3A of the 2nd supporting member 3 located in the lower side. The inner peripheral surface 4A bulges inside the opening H at the corner of the opening H, whereby the wiring board 4 forms a first bulging portion 4B having a planar square shape. Similarly, the wall surface 3A bulges inside the opening H at the corner of the opening H, whereby the second support member 3 forms a second bulging portion 3B having a planar quadrangle. . Such bulging portions 3B and 4B are formed to prevent the upper sealing material 8 from dropping downward.

  In a plurality of printed wirings formed on the wiring board 4, the wiring 4 </ b> C closest to the end of the wiring board 4 is formed with a predetermined clearance from the end of the wiring board 4. An insulating layer (not shown) is formed on the surface of the wiring board 4 on which such wiring is formed. A gap having substantially the same thickness as the wiring 4C is formed between the bulging portions 3B and 4B. Specifically, the thickness of the gap is preferably 0.8 to 1.2 times the thickness of the wiring 4C. The thickness means the height in the vertical direction. The lower sealing material 7 is poured into a sealing material reservoir between the element substrate 2 and the wiring substrate 4 and arranged. The lower sealing material 7 seals the element substrate 2 and the wiring substrate 4 with a sealing material reservoir. The encapsulating material reservoir includes a corner space Cs located at the corner C thereof. The corner C of the sealing material reservoir is located at the corner of the opening H. Here, the corner space Cs is a gap between the bulging portions 3B and 4B.

  In the present embodiment, when pouring the lower sealing material 7, in particular, in order to suppress the occurrence of air bubble containment between the bulging portions 3B, 4B, the member 10 for filling the space between them is provided. I have. That is, a member that at least partially fills the corner space Cs is provided in the corner portion C of the sealing material reservoir. The member 10 may be provided integrally with the wiring board 4 or may be provided separately. This member 10 ensures a gap between the second support member 3 and the peripheral portion of the opening H in the wiring board 4 by contacting the second support member 3.

  By providing such a member 10, the lower sealing material 7 can easily flow into the region between the wiring board 4 and the second support substrate, and the lower sealing material between the bulging portions 3B and 4B. 7 inflow range can be reduced. The lower sealing material 7 flows between the wiring board 4 and the second supporting board as indicated by a line L1 in FIG. As a result, entrapment of bubbles when the lower sealing material 7 flows between the wiring substrate 4 and the second support substrate, and containment of bubbles by the lower sealing material 7 between the bulging portions 3B and 4B. Generation can be suppressed. Thereby, the lower sealing material 7 can express an insulating protection function satisfactorily.

  3A and 3B are explanatory views of a comparative example that does not include the member 10. In this comparative example, the lower sealing material 7 flows between the wiring board 4 and the second support board as shown by lines L11 to L12 in FIG. 3A, and between the bulging portions 3B and 4B. Containment of the bubble A occurs in FIG. The bubbles A thus encapsulated may expand during the thermosetting of the lower sealing material 7 and push the lower sealing material 7 to the outside. In this case, the optimal form after the thermosetting of the lower sealing material 7 cannot be maintained, and the insulating protection function of the lower sealing material 7 may be impaired. In addition, as the thickness of the wiring formed on the wiring substrate 4 increases, the amount of the lower sealing material 7 flowing into the space between the wiring substrate 4 and the second support substrate increases. It becomes higher and the bubble A becomes larger.

  The member 10 may be made of metal. In this case, the member 10 can be efficiently provided by forming the member 10 simultaneously with the step of forming the printed wiring on the wiring board 4. The metal member 10 may be a wiring (main wiring) itself formed on the wiring board 4. In this case, the clearance between the end of the wiring board 4 and the member 10 needs to be equal to the clearance between the end of the wiring board 4 and the wiring. Further, the metal member 10 may be formed separately from the wiring (main wiring) on the wiring board 4. In this case, the boundary which controls the inflow range of the lower sealing material 7 can be determined by the member 10 separated from the wiring. As a result, the lower sealing material 7 more reliably exhibits an insulation protection function, and more reliably suppresses contact between foreign matter such as ink and the wiring of the wiring board 4, thereby further improving the reliability of the recording head. Can be improved.

(Second Embodiment)
As shown in FIGS. 4A and 4B, the deployment position of the member 10 in the present embodiment is the position on the left side in FIG. 4A between the bulging portions 3B and 4B, that is, in FIG. Thus, it is limited to the position on the side where the inner leads 6 are arranged. Between the first support member 1 and the wiring substrate 4, the electrode pads 5 and the inner leads 6 are arranged along the vertical direction in FIG. The lower sealing material 7 tends to flow into the corner portion of the opening H from the electrode pad 5, the inner lead 6, and the connection portion side. The member 10 of this example can effectively suppress such a flow of the lower sealing material 7. Moreover, it can also be efficiently provided by making the member 10 small.

(Third embodiment)
In the present embodiment, as shown in FIGS. 5A and 5B, the slit S is formed in the member 10 in the first embodiment. In the case of this example, the member 10 is divided into two portions 10A and 10B, and a groove portion into which the lower sealing material 7 flows is formed by a slit S between them. With such a slit S, the lower sealing material 7 can be wound around a predetermined position.

(Fourth embodiment)
In the first, second, and third embodiments, the member 10 is provided on the wiring board 4. However, the same member 10 as those embodiments may be provided on the second support member 3. In this case, for example, a protrusion having the same form as that of the member 10 can be provided on the second support member 3.

(Other embodiments)
The first and second support members in the above-described embodiments may be integrated, or a combination of three or more members. In short, it is sufficient that the recording element substrate 2 and the wiring substrate 4 that are electrically connected can be supported. Further, the shape of the sealing material reservoir is not limited to the planar square frame shape as in the above-described embodiment. In the case where the encapsulating material reservoir has a planar square frame shape, the corner may be a portion of four corners, or may be located on one side of two sides forming the corner. Further, the member for filling the corner space of the sealing material reservoir can be provided on at least one of the recording element substrate, the wiring substrate, and the support member. In short, any member that can at least partially fill the corner space may be used.

  The present invention is applicable not only to a recording head that ejects ink but also to a liquid ejection head that ejects various liquids. Such a liquid discharge head can be provided in a liquid discharge apparatus that executes various processes for discharging liquid.

DESCRIPTION OF SYMBOLS 1 1st support member 2 Recording element board | substrate 3 2nd support member 4 Wiring board 7 Lower sealing material 8 Upper sealing material 10 Member C Corner | edge part Cs Corner | edge part space

Claims (13)

An element substrate provided with an ejection energy generating element for ejecting liquid from an ejection port, a wiring substrate electrically connected to the element substrate, a support member for supporting the element substrate and the wiring substrate, and the element A sealing material that seals between a substrate and the wiring substrate with a sealing material reservoir between the element substrate and the wiring substrate, and a liquid ejection head comprising:
The sealing material reservoir includes a corner space located at a corner of the sealing material reservoir,
A liquid ejection head comprising: a member that at least partially fills the corner space in the corner.   The liquid ejection head according to claim 1, wherein the member is provided on at least one of the element substrate, the wiring substrate, and the support member that are positioned at the corner.   3. The liquid ejection head according to claim 1, wherein the corner space includes a gap between the wiring board located at the corner and the support member.   The said clearance gap is formed between the 1st bulging part of the said wiring board located in the said corner | angular part, and the 2nd bulging part of the said supporting member located in the said corner | angular part. Liquid discharge head. The wiring board has a wiring formed on a surface bonded to the support member,
5. The liquid ejection head according to claim 3, wherein a thickness of the gap is not less than 0.8 times and not more than 1.2 times the thickness of the wiring.   The liquid ejection head according to claim 1, wherein the member is configured by wiring formed on the wiring board.   The liquid ejection head according to claim 6, wherein the wiring constituting the member is a wiring electrically connected to the element substrate.   The liquid ejection head according to claim 6, wherein the wiring constituting the member is a wiring that is not electrically connected to the element substrate.   The liquid discharge head according to claim 1, wherein the member is a metal.   The liquid ejection head according to claim 1, wherein the member has a groove portion into which the sealing material flows. The support member includes a first support member that supports the element substrate, and a second support member that supports the wiring substrate and the first support member,
11. The liquid ejection head according to claim 1, wherein the sealing material reservoir includes a space between the first support member and the second support member.   The liquid according to any one of claims 1 to 11, wherein the sealing material includes a lower sealing material poured into a sealing material reservoir and an upper sealing material positioned on the lower sealing material. Discharge head.   A liquid discharge apparatus comprising the liquid discharge head according to claim 1.