JPWO2015080033A1 - Wiring board and inkjet head - Google Patents

Abstract

The flatness of the surface on which the wiring is formed is improved. A wiring board 6 is disposed so that the wiring surface 600 on which the lower wiring 6g for transmitting electricity is formed is opposed to another member, and the lower wiring is formed on the wiring surface of the board body. And a non-wiring area A2 in which an inlet 6i is provided so that an opening faces the other member side, and the non-wiring area and the wiring area are the other areas. The relative positions with respect to the members are substantially equal.

Description

  The present invention relates to a wiring board on which wiring is formed and an inkjet head.

2. Description of the Related Art Conventionally, an inkjet head is known that includes a wiring board on which wiring for supplying power to an actuator that discharges ink from nozzles is formed (see, for example, Patent Document 1). Specifically, the inkjet head is configured by laminating a wiring substrate with an adhesive on a head chip having a nozzle substrate having nozzles, a pressure chamber substrate having pressure chambers, and the like.
Some wiring boards have an ink flow path in addition to the wiring, and are bonded after being positioned with respect to the corresponding position of the head chip.

JP 2012-126029 A

  Incidentally, an insulating film such as polyimide or silicon oxide is formed on one surface of the wiring board. However, since the thickness is different between the wiring region where the wiring is formed on one surface of the wiring substrate and the non-wiring region where the wiring is not formed, the surface of the substrate is covered with an insulating film. It is not easy to ensure flatness. In particular, when the adhesion between the peripheral area of the ink flow path in the non-wiring area of the wiring board and the head chip is lowered, there is a possibility that ink leakage from the ink flow path occurs.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a wiring board and an ink jet head capable of improving the flatness of the surface on which the wiring is formed.

In order to solve the above problems, the wiring board according to the first aspect of the present invention provides:
A wiring board disposed with a wiring surface on which wiring for transmitting electricity is formed facing another member,
The wiring surface includes a wiring region where the wiring is formed, and a non-wiring region where the wiring is not formed and a liquid flow path is provided so as to face an opening on the other member side,
The non-wiring area and the wiring area are configured such that their relative positions with respect to the other members are substantially equal.

The invention according to claim 2 is the wiring board according to claim 1,
In the non-wiring area, a thickness adjusting member having substantially the same thickness as the wiring in the wiring area is provided.

The invention according to claim 3 is the wiring board according to claim 2,
The thickness adjusting member is provided in a peripheral region of the liquid channel opening in the non-wiring region.

The invention according to claim 4 is the wiring board according to claim 2 or 3,
The thickness adjusting member has a linear shape,
A plurality of the thickness adjusting members are arranged in almost all the non-wiring region.

Invention of Claim 5 is a wiring board as described in any one of Claims 2-4,
The thickness adjusting member includes a pseudo wiring that is not electrically connected.

The invention according to claim 6 is the wiring board according to claim 5,
The width of the pseudo wiring is substantially equal to the width of the wiring.

The invention according to claim 7 is the wiring board according to claim 5 or 6,
A plurality of the wirings and the pseudo wirings are provided,
An interval between adjacent ones of the plurality of pseudo wires is approximately equal to an interval between adjacent ones of the plurality of wires.

The invention according to claim 8 is the wiring board according to any one of claims 1 to 7,
The wiring surface is covered with an insulating film.

The inkjet head of the invention according to claim 9 is
The wiring board according to any one of claims 1 to 8,
A head chip in which one surface facing the wiring surface is bonded to the wiring surface of the wiring substrate via an adhesive;
It is characterized by having.

  According to the present invention, the flatness of the surface on which the wiring is formed can be improved.

It is a fragmentary sectional view showing a schematic structure of an ink jet head of one embodiment to which the present invention is applied. It is a figure which shows typically the state which isolate | separated the head chip and wiring board which comprise the inkjet head of FIG. It is a figure which shows typically the wiring surface of the wiring board of FIG. It is a figure which shows typically the cross section of the part shown by the IV-IV line of the wiring board of FIG. It is a figure which shows typically the wiring surface of the wiring board of the modification 1. FIG. It is a figure which shows typically the wiring surface of the wiring board of the modification 2.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a partial cross-sectional view showing a schematic configuration of an inkjet head 100 according to an embodiment to which the present invention is applied. FIG. 2 is a diagram schematically showing a state where the head chip 100A and the wiring board 6 constituting the ink jet head are separated.
The inkjet head 100 is generally provided with a plurality of nozzles 1a, but FIG. 1 schematically shows only the components related to one nozzle 1a.

  As shown in FIG. 1, the inkjet head 100 includes a nozzle substrate 1, a first bonding substrate 2, a pressure chamber substrate 3, a second bonding substrate 4, a piezoelectric element 5, and a wiring substrate 6 that are stacked in this order. It is configured. The nozzle substrate 1, the first bonding substrate 2, the pressure chamber substrate 3, the second bonding substrate 4 and the piezoelectric element 5 constitute a head chip 100 </ b> A.

The nozzle substrate 1 is located in the lowermost layer of the inkjet head 100. The nozzle substrate 1 is, for example, a silicon substrate. The nozzle substrate 1 is formed with a plurality of nozzles 1a (only one is shown in FIG. 1).
The nozzles 1a are arranged on the nozzle surface so as to have a substantially matrix shape, for example.

The first bonding substrate 2 is laminated on the upper surface of the nozzle substrate 1 and bonded via an adhesive (not shown). The first bonding substrate 2 is, for example, a glass substrate. The first bonding substrate 2 is formed with a through hole 2a that communicates with the nozzle 1a of the nozzle substrate 1 and forms an ink flow path.
Further, the pressure chamber substrate 3 is laminated and bonded on the upper surface of the first bonding substrate 2.

The pressure chamber substrate 3 is composed of a pressure chamber layer 3a and a diaphragm 3b.
The pressure chamber layer 3a is laminated on the upper surface of the first bonding substrate 2 and bonded thereto. The pressure chamber layer 3a is made of a silicon substrate. In the pressure chamber layer 3a, a pressure chamber 3c that applies a discharge pressure to the ink discharged from the nozzle 1a is formed so as to penetrate the pressure chamber layer 3a.
The pressure chamber 3c is provided above the through hole 2a and the nozzle 1a, and communicates with the through hole 2a and the nozzle 1a.
The diaphragm 3b is laminated and bonded to the upper surface of the pressure chamber layer 3a so as to cover the opening of the pressure chamber 3c. That is, the diaphragm 3b constitutes the upper wall portion of the pressure chamber 3c. Moreover, for example, an oxide film is formed on the surface of the diaphragm 3b.
A second bonding substrate 4 is laminated and bonded on the upper surface of the vibration plate 3b.

  The second bonding substrate 4 is laminated on the upper surface of the vibration plate 3b and bonded via an adhesive G (see FIG. 2). The second bonding substrate 4 is made of, for example, a photosensitive resin. A space 4 a for accommodating the piezoelectric element 5 is formed inside the second bonding substrate 4. The space 4a is formed above the pressure chamber 3c so as to penetrate the second bonding substrate 4.

  The piezoelectric element 5 is formed in substantially the same plan view shape as the pressure chamber 3c, and is provided at a position facing the pressure chamber 3c with the diaphragm 3b interposed therebetween. The piezoelectric element 5 is an actuator made of PZT (lead zirconium titanate) for deforming the diaphragm 3b. An electrode (not shown) provided on the lower surface of the piezoelectric element 5 is connected to the diaphragm 3b.

Further, the second bonding substrate 4 is formed with a through hole 4b communicating with the communication hole 3d of the pressure chamber substrate 3 independently of the space portion 4a.
A wiring substrate 6 is laminated and bonded on the upper surface of the second bonding substrate 4.

The wiring board 6 includes an interposer 6a that is a silicon substrate, for example.
The interposer 6a is formed in a plate shape having a thickness substantially equal to the stacking direction of the substrates. The lower surface of the interposer 6a is covered with two insulating layers 6b and 6c, and the upper surface is covered with a single insulating layer 6d. The insulating layers 6b to 6d are made of an insulating material such as polyimide or silicon oxide, for example. Of the two insulating layers 6b and 6c below the interposer 6a, the lower insulating layer 6c is laminated on the upper surface of the second bonding substrate 4 and bonded thereto.
The interposer 6a has a through hole 6e formed in the stacking direction, and a through electrode 6f is inserted into the through hole 6e. One end of a lower wiring 6g extending in the horizontal direction is connected to the lower end of the through electrode 6f. The other end of the lower wiring 6g is provided with a stud bump 6h exposed in the space 4a and connected to a solder 5a provided on an electrode (not shown) on the upper surface of the piezoelectric element 5. The lower wiring 6g is protected by being sandwiched between two insulating layers 6b and 6c on the lower side of the interposer 6a. That is, the wiring surface 600 on which the lower wiring 6g of the wiring board 6 is formed is covered with an insulating film.
The interposer 6a is formed with an inlet 6i that communicates with the through hole 4b of the second bonding substrate 4 so as to penetrate the interposer 6a in the vertical direction. That is, the inlet 6i is provided so that the opening faces the second bonding substrate 4 side.

Further, on the upper surface of the wiring board 6, an upper wiring 6j having one end connected to the upper end of the through electrode 6f and the other end connected to an electrical connector (not shown) via a relay board (not shown) or the like. It is arranged.
An adhesive layer 6k is formed so as to cover the upper wiring 6j on the upper surface of the wiring substrate 6 and the upper surface of the insulating layer 6d of the interposer 6a. The adhesive layer 6k is made of, for example, a photosensitive resin for bonding the inkjet head 100 to a holding plate (not shown). The adhesive layer 6k constitutes a protective layer that protects the upper wiring 6j. The adhesive layer 6k is formed with a through hole 61 that communicates with the inlet 6i.

The wiring board 6 having such a configuration is bonded via the adhesive G with the wiring surface 600 on which the lower wiring 6g is formed facing the upper surface of the second bonding substrate 4 of the head chip 100A. (See FIG. 2).
A specific configuration of the wiring surface 600 of the wiring board 6 will be described later.

  The communication hole 3d, the through holes 2a, 4b, 6l and the inlet 6i of the ink jet head 100 constitute an ink flow path, and ink in an ink chamber (not shown) is supplied to the nozzle 1a through the ink flow path.

Next, a specific configuration of the wiring board 6 will be described with reference to the drawings.
FIG. 3 is an enlarged view schematically showing a part of the wiring surface 600 of the wiring board 6, and FIG. 4 is an enlarged view schematically showing a cross section of the portion indicated by the IV-IV line of the wiring board 6. FIG.
In FIG. 4, illustration of the insulating layer 6c and the adhesive G is omitted.

  As shown in FIGS. 3 and 4, a lower wiring 6g is formed in a partial region of the wiring surface 600 of the wiring substrate 6, and a region where the lower wiring 6g is formed constitutes a wiring region A1. The region where the lower wiring 6g is not formed constitutes the non-wiring region A2.

  As shown in FIG. 4, an insulating layer 6 b is formed on the surface of the interposer 6 a of the wiring board 6 on the second bonding substrate 4 side (lower end surface in FIG. 4). The insulating layer 6b is formed in a region other than a portion provided with, for example, an inlet 6i, a through hole 6e, a through electrode 6f, or the like constituting the ink flow path on the surface of the interposer 6a on the second bonding substrate 4 side. Has been. The insulating layer 6b has a thickness that is substantially equal to the stacking direction of the substrates.

A plurality of lower wirings 6g are arranged on the surface of the insulating layer 6b on the second bonding substrate 4 side (lower end surface in FIG. 4). The plurality of lower wirings 6g,... Are arranged so as to avoid, for example, the inlet 6i, the through hole 6e, the through electrode 6f, and the like constituting the ink flow path. Specifically, for example, as shown in FIG. 3, in the vicinity of the inlet 6i of the non-wiring region A2 (on the right end side in FIG. 3), a plurality of lower wirings 6g,. They are arranged side by side with a substantially equal interval S1.
The plurality of lower wirings 6g,... Have a shape that increases the interval between adjacent ones on the left end side in FIG.

In addition, each of the plurality of lower wirings 6g,... Has a predetermined thickness T1 in the substrate stacking direction, and a direction in which most of the lower wiring 6g extends (for example, the X direction). A predetermined width W1 is provided in a direction substantially orthogonal to (for example, the Y direction).
Note that the thickness T1, the width W1, and the interval S1 between the wirings of the lower wiring 6g can be arbitrarily changed as appropriate. Further, for example, the width W1 of the lower wiring 6g and the interval S1 between the wirings may be set to have a predetermined ratio.

In the non-wiring area A2, a pseudo wiring 700 having a thickness substantially equal to that of the lower wiring 6g is disposed.
The pseudo wiring 700 is a linear wiring that is not electrically connected, and a plurality of pseudo wirings 700 are provided in almost all areas of the non-wiring area A2. Specifically, in the non-wiring region A2, for example, a plurality of linear pseudo wirings that are linearly formed so as to extend in a direction substantially equal to the plurality of lower wirings 6g,. 701, ... are provided. The plurality of linear pseudo wires 701,... Are arranged in parallel with a predetermined interval S2 substantially equal to the interval between the lower wires 6g.
Further, in the non-wiring area A2, for example, two arc-shaped pseudo wirings 702 and 702 formed in an arc shape are provided in the peripheral area of the opening of each inlet 6i in the non-wiring area A2. These two arc-shaped pseudo wires 702 and 702 are arranged so as to sandwich the opening of the inlet 6i in the X direction.

Further, each of the linear pseudo wiring 701 and the arc-shaped pseudo wiring 702 has a predetermined thickness T2 substantially equal to the lower wiring 6g. Further, each of the straight pseudo wiring 701 and the arc pseudo wiring 702 has a predetermined width W2 substantially equal to the lower wiring 6g.
Note that the thickness T2, the width W2, and the interval S2 between the wirings of the pseudo wiring 700 can be arbitrarily changed as appropriate. Further, for example, the width W2 of the pseudo wiring 700 and the distance S2 between the wirings may be set to have a predetermined ratio.

As described above, the pseudo wiring 700 disposed in the non-wiring area A2 constitutes a thickness adjusting member having a thickness substantially equal to that of the lower wiring 6g of the wiring area A1. Thereby, the distances from the respective surfaces (the lower end surface in FIG. 4) of the pseudo wiring 700 in the non-wiring area A2 and the lower wiring 6g of the wiring area A1 to the second bonding substrate 4 are substantially equal.
That is, the non-wiring region A2 and the wiring region A1 including the peripheral region of the opening of the inlet (liquid channel) 6i are substantially equal in relative position to the second bonding substrate (other member) 4 in the substrate stacking direction. Has been.

  In addition, as a material of the lower wiring 6g and the pseudo wiring 700, for example, Cu, Au or the like can be cited, and it is preferable that the lower wiring 6g and the pseudo wiring 700 are made of the same material.

As described above, according to the inkjet head 100 of the present embodiment, the wiring region A1 in which the lower wiring 6g is formed and the lower wiring 6g are not formed on the wiring surface 600 in the substrate body of the wiring substrate 6. A non-wiring region A2 provided with an inlet 6i so that the opening faces the second bonding substrate 4 side of the head chip 100A. The non-wiring region A2 and the wiring region A1 are the second bonding substrate. Since the relative position with respect to (other member) 4 is substantially equal, the surface shape (particularly the thickness) of the non-wiring region A2 provided with the inlet 6i and the lower wiring 6g are formed. The surface shape of the wiring area A1 can be made more similar. Thereby, even if the insulating layer 6c is formed on the wiring surface 600 of the wiring substrate 6, the surface shape of the non-wiring region A2 and the surface shape of the wiring region A1 can be made similar. In particular, for example, even when the insulating layer 6c is made of fluid polyimide or the like, the non-wiring region A2 and the wiring region A1 have substantially the same cured state of the insulating layer (for example, polyimide) 6c. can do.
Therefore, it is possible to improve the flatness of the region from the wiring region A1 where the lower wiring 6g is formed on the wiring surface 600 of the wiring substrate 6 to the non-wiring region A2 where the inlet 6i is provided. As a result, even if the head chip 100A is bonded to the wiring surface 600 of the wiring board 6 via the adhesive G, the adhesiveness between the non-wiring area A2 of the wiring board 6 and the head chip 100A decreases or the adhesive G Cracks and the like can be suppressed, and ink leakage from the ink flow path can be made difficult to occur.
In particular, the opening of the inlet 6i in the non-wiring area A2 by the thickness adjusting member (for example, the arcuate pseudo wiring 702) provided in the peripheral area of the opening of the inlet 6i in the non-wiring area A2 on the wiring surface 600. As a result, it is possible to suitably suppress a decrease in adhesion between the peripheral region of the head and the head chip 100A, a crack in the adhesive G, and the like, and as a result, it is possible to appropriately suppress ink leakage from the ink flow path.

Specifically, since the pseudo wiring 700 as a thickness adjusting member having a thickness substantially equal to the lower wiring 6g of the wiring area A1 is disposed in the non-wiring area A2 of the wiring surface 600 of the wiring board 6, By using the pseudo wiring 700, each surface (lower end surface in FIG. 4) of the pseudo wiring 700 (linear pseudo wiring 701, arc-shaped pseudo wiring 702) in the non-wiring area A2 and the lower wiring 6g of the wiring area A1. To the second bonding substrate 4 can be easily adjusted at low cost. That is, when the lower wiring 6g is disposed on the wiring substrate 6, for example, the pseudo wiring 700 made of the same material as the lower wiring 6g can be efficiently formed.
In addition, since a plurality of pseudo wirings 700 as thickness adjusting members are provided in almost all areas of the non-wiring area A2, the non-wiring area A2 is a wiring area in which a plurality of lower wirings 6g are formed. It can be set as the structure substantially the same as A1.
In particular, the width W2 of the pseudo wiring 700 is substantially equal to the width W1 of the lower wiring 6g, or the interval S2 between adjacent ones of the plurality of pseudo wirings 700 is adjacent to the plurality of lower wirings 6g,. By making the interval S1 between the two substantially equal, the surface shape of the non-wiring region A2 and the surface shape of the wiring region A1 can be made more similar.

The present invention is not limited to the above-described embodiment, and various improvements and design changes may be made without departing from the spirit of the present invention.
Below, the modification of arrangement | positioning of the thickness adjustment member in the wiring surface 600 of the wiring board 6 is demonstrated.
Further, in the modified example described below, points other than the arrangement of the pseudo wiring 700 as the thickness adjusting member are substantially the same as those in the above embodiment, and detailed description thereof is omitted.

<Modification 1>
FIG. 5 is a diagram schematically showing an enlarged part of the wiring surface 600 of the wiring board 106 according to the first modification.
As shown in FIG. 5, in the non-wiring area A2 on the wiring surface 600 of the wiring board 106 of the first modification, one end portion extends to the peripheral area of the opening of the inlet 6i as a thickness adjusting member. A plurality of linear pseudo wires 701,... Are provided.

  That is, a plurality of linear pseudo wires 701,... Are provided in the non-wiring region A2, and among these, a predetermined number of linear pseudo wires 701 sandwiching the opening of the inlet 6i in the X direction are provided on the inlet 6i side. The end extends to the peripheral region of the opening of the inlet 6i. In other words, in the non-wiring area A2, instead of the arc-shaped pseudo wiring 702 in the above embodiment, a plurality of linear pseudo wirings having one end extending to the peripheral area of the opening of the inlet 6i. 701 are arranged.

  Even in such a configuration, the surface shape of the non-wiring region A2 on the wiring surface 600 of the wiring substrate 106 can be made more similar to the surface shape of the wiring region A1, and the lower wiring 6g on the wiring surface 600 of the wiring substrate 106 can be made. It is possible to improve the flatness of the region extending from the wiring region A1 in which is formed to the non-wiring region A2 in which the inlet 6i is provided. As a result, even if the head chip 100A is bonded to the wiring surface 600 of the wiring board 106 via the adhesive G, the adhesiveness between the non-wiring area A2 of the wiring board 106 and the head chip 100A is reduced or the adhesive G is used. Cracks and the like can be suppressed, and ink leakage from the ink flow path can be made difficult to occur.

<Modification 2>
FIG. 6 is a diagram schematically showing an enlarged part of the wiring surface 600 of the wiring board 206 of the second modification.
As shown in FIG. 6, in the non-wiring area A2 on the wiring surface 600 of the wiring board 206 of the second modification, the arc-shaped pseudo wiring 702 in the above embodiment is not provided as a thickness adjusting member, Only the linear pseudo wires 701,... Are provided.

  That is, the wiring board 206 of Modification 2 includes a plurality of linear pseudo wirings 701,... And a plurality of arcuate pseudo wirings 702 disposed in the non-wiring area A2 of the wiring surface 600 of the wiring board 6 of the above embodiment. ,... Are only arranged in the non-wiring region A2.

Thus, in the non-wiring area A2 of the wiring surface 600 of the wiring board 206, the thickness of the pseudo wiring 700 (for example, the linear pseudo wiring 701 or the arc pseudo wiring 702) is not necessarily provided in the peripheral area of the opening of the inlet 6i. Even without the adjustment member, the flatness of the region from the wiring region A1 where the lower wiring 6g is formed on the wiring surface 600 of the wiring substrate 206 to the non-wiring region A2 where the inlet 6i is provided is improved. be able to.
As a result, even if the head chip 100A is bonded to the wiring surface 600 of the wiring board 206 via the adhesive G, the adhesiveness between the non-wiring area A2 of the wiring board 206 and the head chip 100A is reduced or the adhesive G is used. Cracks and the like can be suppressed, and ink leakage from the ink flow path can be made difficult to occur.

  Moreover, in the said embodiment and the modifications 1 and 2, although the several pseudo wiring 700 formed in linear form was illustrated as a thickness adjustment member, for example, it is an example and it is not restricted to this, For example, Further, it may be formed in a flat plate shape extending in a direction substantially orthogonal to the stacking direction of the substrates. Further, the thickness adjusting member is set so that the relative positions of the non-wiring region A2 (particularly, the peripheral region of the opening of the inlet 6i) and the wiring region A1 with respect to the second bonding substrate (other member) 4 are substantially equal. The pseudo wiring 700 is not necessarily required as long as it is for adjustment.

  Further, in the above embodiment, the thickness adjusting member such as the pseudo wiring 700 is arranged in the non-wiring region A2 of the wiring board 6 to adjust the thickness. However, the thickness is adjusted only as an example. For example, the relative position of the portion corresponding to the non-wiring region A2 of the interposer 6a with respect to the second bonding substrate 4 is substantially equal to the relative position of the lower wiring 6g with respect to the second bonding substrate 4. Alternatively, the interposer 6a may be processed in advance. Further, for example, the portion itself corresponding to the non-wiring region A2 of the second bonding substrate 4 bonded to the wiring substrate 6 may be processed in advance so as to have a thickness substantially equal to the lower wiring 6g.

  Furthermore, it is needless to say that other specific detailed structures can be appropriately changed. For example, in the above embodiment, the width W2 of the pseudo wiring 700 is set to be substantially equal to the width W1 of the lower wiring 6g. However, the width is not limited to this example and can be arbitrarily changed. Further, for example, the interval S2 between the linear pseudo wires 701 is substantially equal to the interval S1 between the lower wires 6g. However, the interval S2 is not limited to this example, and can be arbitrarily changed as appropriate. .

  In addition, it should be thought that embodiment disclosed this time is an illustration and restrictive at no points. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  The present invention can be used for a wiring board on which wiring is formed and an inkjet head.

100 inkjet head 100A head chip 1 nozzle substrate 2 first bonding substrate 3 pressure chamber substrate 4 second bonding substrate 5 piezoelectric elements 6, 106, 206 wiring substrate 6g lower wiring 600 wiring surface 700 pseudo wiring 701 linear pseudo wiring 702 Arc-like pseudo wiring A1 Wiring area A2 Non-wiring area

Claims (9)

A wiring board disposed with a wiring surface on which wiring for transmitting electricity is formed facing another member,
The wiring surface includes a wiring region where the wiring is formed, and a non-wiring region where the wiring is not formed and a liquid flow path is provided so as to face an opening on the other member side,
The wiring board, wherein the non-wiring region and the wiring region are configured so that their relative positions with respect to the other members are substantially equal.   The wiring board according to claim 1, wherein a thickness adjusting member having a thickness substantially equal to that of the wiring in the wiring region is disposed in the non-wiring region.   The wiring board according to claim 2, wherein the thickness adjusting member is disposed in a peripheral region of the opening of the liquid channel in the non-wiring region. The thickness adjusting member has a linear shape,
4. The wiring board according to claim 2, wherein a plurality of the thickness adjusting members are disposed in substantially all areas of the non-wiring area. 5.   The wiring board according to claim 2, wherein the thickness adjusting member includes a pseudo wiring that is not electrically connected.   The wiring board according to claim 5, wherein a width of the pseudo wiring is substantially equal to a width of the wiring. A plurality of the wirings and the pseudo wirings are provided,
The wiring board according to claim 5, wherein an interval between adjacent ones of the plurality of pseudo wires is substantially equal to an interval between adjacent ones of the plurality of wires.   The wiring board according to claim 1, wherein the wiring surface is covered with an insulating film. The wiring board according to any one of claims 1 to 8,
A head chip in which one surface facing the wiring surface is bonded to the wiring surface of the wiring substrate via an adhesive;
An ink jet head comprising:

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