JP2016030402A - Manufacturing method of liquid jet head, and liquid jet head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method of a liquid jet head which can secure electrical connection between an electrode terminal and a wiring terminal by reducing positional deviation between the electrode terminal of a head chip and the wiring terminal of a flexible substrate.SOLUTION: A manufacturing method of a liquid jet head includes: a preparation process S1 of preparing a head chip with a plurality of electrode terminals arrayed, and a flexible substrate having a terminal region with a plurality of wiring terminals arrayed; an arrangement process S2 of causing the plurality of electrode terminals to face the plurality of wiring terminals respectively and arranging the flexible substrate on the head chip; a temporary crimping process S3 of fixing the flexible substrate to the head chip by thermally compressing peripheries of both ends of the terminal region in a direction of arraying the wiring terminals; and a main crimping process S4 of electrically connecting the plurality of electrode terminals and the plurality of wiring terminals respectively by thermally compressing the flexible substrate to the head chip.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a liquid ejecting head and a liquid ejecting head that perform recording by discharging droplets onto a recording medium.

  In recent years, an ink jet type liquid ejecting head has been used in which ink droplets are ejected onto recording paper or the like to record characters and figures, or a liquid material is ejected onto the surface of an element substrate to form a functional thin film. In this method, a liquid such as ink or a liquid material is guided from a liquid tank to a pressure chamber via a supply pipe, pressure is applied to the liquid filled in the pressure chamber, and the liquid is discharged from a nozzle communicating with the pressure chamber. When the liquid is ejected, the liquid ejecting head or the recording medium is moved to record characters or figures, or a functional thin film or a three-dimensional structure having a predetermined shape is formed.

  This type of liquid jet head includes a head chip in which a plurality of channels are arranged. The head chip includes electrode terminals for inputting drive signals for independently driving a plurality of channels. The plurality of electrode terminals are arranged on the surface of the head chip, and a flexible substrate is connected to the surface. The flexible substrate includes a plurality of wirings that transmit a drive signal and a plurality of wiring terminals that are ends of the wirings. The plurality of wiring terminals of the flexible substrate are electrically connected to the plurality of electrode terminals of the head chip, respectively. Therefore, the drive signal is independently supplied to each channel via the wiring of the flexible substrate, the wiring terminal, and the electrode terminal of the head chip. The flexible substrate is connected to the head chip by thermocompression bonding. Specifically, an anisotropic conductive sheet is interposed between the head chip and the flexible substrate, and each electrode terminal of the head chip and each wiring terminal of the flexible substrate are opposed to each other and connected together by thermocompression bonding. . Thereby, each electrode terminal and each wiring terminal are electrically connected independently.

Japanese Patent Laid-Open No. 06-97615

  In recent years, as the number of nozzles of a liquid jet head increases and the recording density becomes higher, the number of electrode terminals increases and the arrangement pitch of electrode terminals becomes narrower. On the other hand, when thermocompression bonding a large number of electrode terminals and a large number of wiring terminals, misalignment occurs between the electrode terminals and the wiring terminals due to the difference in thermal expansion between the head chip and the flexible substrate, resulting in poor connection and reliability. It is also the cause of the decline.

  For example, in Patent Document 1, when an FPC (flexible printed circuit board) is connected to an LCD (liquid crystal display) by thermocompression bonding, due to the difference in coefficient of linear expansion between the glass for LCD and the polyimide film for FPC, It is described that pattern deviation occurs. In order to improve this, in patent document 1, the material which reduced the linear expansion coefficient is used as a film for FPC. However, the head chip of the liquid jet head is different from the glass for LCD. Further, the thermal expansion of the FPC is easily influenced by the conductor material and pattern shape used for the FPC.

  The method of manufacturing a liquid jet head according to the present invention includes a preparation step of preparing a head chip in which a plurality of electrode terminals are arranged and a flexible substrate having a terminal region in which a plurality of wiring terminals are arranged, the plurality of electrode terminals, and the plurality of electrode terminals. Each of the wiring terminals is opposed to each other, and the flexible substrate is disposed on the head chip, and the flexible substrate and the head chip are bonded by thermocompression bonding in the vicinity of both ends of the terminal region in the direction in which the wiring terminals are arranged. A temporary crimping step of fixing, and a main crimping step of thermally connecting the flexible substrate to the head chip to electrically connect the plurality of electrode terminals and the plurality of wiring terminals, respectively.

  Further, the arranging step includes a temporary fixing step of heating the terminal region and temporarily fixing the flexible substrate and the head chip after performing alignment between the flexible substrate and the head chip. .

  In addition, the region fixed in the temporary press-bonding step is defined as a fixed region, and the main press-bonding step is performed by thermo-compressing a region between the fixed regions and in contact with the fixed region.

  Further, in the main press bonding step, a part of the fixed region is overlapped and thermocompression bonded.

  Moreover, the heating temperature in the temporary press-bonding step is higher than the heating temperature in the main press-bonding step.

  Further, in the arranging step, the flexible substrate in the vicinity of at least one end of the terminal region is arranged on a side surface of the head chip, and in the temporary crimping step, the flexible substrate in the vicinity of the end is arranged on the side surface of the head chip. It was decided to fix by thermocompression.

  In addition, the flexible substrate has a convex region corresponding to the terminal region and protruding from a surface opposite to a surface on which the wiring terminals are arranged, and the main crimping step includes an upper end surface of the convex region. Was subjected to thermocompression bonding.

  The electrode terminals include a common electrode terminal and individual electrode terminals, the plurality of common electrode terminals and the plurality of individual electrode terminals are arranged in parallel, and the wiring terminals include a common wiring terminal and individual wiring terminals. The common wiring terminal and the plurality of individual wiring terminals are arranged in parallel, and the preparing step includes a plurality of the common electrode terminals, the plurality of common wiring terminals, a plurality of the individual electrode terminals, and the plurality of the individual wiring terminals. Each of the plurality of the common electrode terminals, the plurality of the common wiring terminals, and the plurality of the individual electrode terminals and the plurality of the individual wiring terminals. It was decided to be a process of connecting them.

  Further, the flexible substrate includes a common wiring that is long in the arrangement direction between the arrangement of the common wiring terminals and the arrangement of the individual wiring terminals in the terminal region.

  The liquid ejecting head of the present invention has a terminal region in which a plurality of wiring terminals are arranged, a flexible region having a convex region corresponding to the terminal region and protruding from a surface opposite to the surface on which the wiring terminals are arranged. A substrate was provided.

  The method of manufacturing a liquid jet head according to the present invention includes a preparation step of preparing a head chip in which a plurality of electrode terminals are arranged, a flexible substrate having a terminal region in which a plurality of wiring terminals are arranged, a plurality of electrode terminals, and a plurality of electrode terminals Arrangement step for arranging the flexible substrate on the head chip with the wiring terminals facing each other, a temporary crimping step for fixing the flexible substrate and the head chip by thermocompressing the vicinity of both ends in the direction in which the wiring terminals in the terminal area are arranged, and flexible And a main pressure bonding step in which the substrate and the head chip are thermocompression bonded to electrically connect the plurality of electrode terminals and the plurality of wiring terminals, respectively. Thereby, when the flexible substrate is thermocompression bonded to the head chip, the positional deviation between the electrode terminal and the wiring terminal is reduced, and the electrical connection between the electrode terminal and the wiring terminal can be reliably performed.

FIG. 6 is a process diagram illustrating a method of manufacturing a liquid jet head according to the first embodiment of the present invention. It is explanatory drawing of the manufacturing method of the liquid jet head which concerns on 1st embodiment of this invention. It is explanatory drawing of the manufacturing method of the liquid jet head which concerns on 1st embodiment of this invention. It is explanatory drawing of the manufacturing method of the liquid jet head which concerns on 1st embodiment of this invention. It is explanatory drawing of the manufacturing method of the liquid jet head which concerns on 2nd embodiment of this invention. FIG. 10 is an explanatory diagram of a method for manufacturing a liquid jet head according to a third embodiment of the present invention. It is explanatory drawing of the manufacturing method of the liquid jet head which concerns on 4th embodiment of this invention. It is explanatory drawing of the manufacturing method of the liquid jet head which concerns on 5th embodiment of this invention. It is a cross-sectional schematic diagram of the discharge groove direction showing the modification of 5th embodiment of this invention.

(First embodiment)
FIG. 1 is a process diagram illustrating a method of manufacturing a liquid jet head according to the first embodiment of the invention. 2 to 4 are explanatory views of the method of manufacturing the liquid jet head according to the first embodiment of the invention. FIG. 2A is an explanatory diagram of the preparation process, and is a schematic perspective view of the head chip 2 and the flexible substrate 4. FIG. 2B is an explanatory diagram of the arrangement step S <b> 2, and is a schematic perspective view in a state where the flexible substrate 4 is arranged on the head chip 2. 3A and 3B are explanatory diagrams of the provisional pressure bonding step S3, in which FIG. 3A is a schematic top view, and FIG. 3B is a schematic cross-sectional view of the portion AA. FIG. 4 is an explanatory view of the main press-bonding step S4 and represents a cross section of the portion AA.

  As shown in FIG. 1, the method of manufacturing a liquid jet head according to the present invention includes a preparation step S <b> 1 for preparing a head chip 2 and a flexible substrate 4, an arrangement step S <b> 2 for arranging the flexible substrate 4 on the head chip 2, and a flexible substrate. 4 includes a temporary crimping step S3 for fixing 4 to the head chip 2 and a final crimping step S4 for thermocompression bonding the flexible substrate 4 to the head chip 2. Hereinafter, it demonstrates concretely using FIGS.

  In the preparation step S1, as shown in FIG. 2A, a flexible substrate 4 having a head chip 2 in which a plurality of electrode terminals 3 are arranged and a terminal region TR in which a plurality of wiring terminals 5 are arranged is prepared. The head chip 2 includes an actuator substrate 10 made of a piezoelectric material such as PZT (lead zirconate titanate) ceramics, a cover plate 11 bonded to the upper surface US of the actuator substrate 10, and the actuator substrate 10 and the front end face Ta of the cover plate 11. And a nozzle plate 12 to be joined to each other. The head chip 2 includes electrode terminals 3 arranged in the reference direction K on the upper surface US near the rear end surface Tb of the actuator substrate 10. The cover plate 11 is bonded to the upper surface US of the actuator substrate 10 with an adhesive so that the electrode terminals 3 are exposed. The flexible substrate 4 includes a terminal region TR in which a plurality of wiring terminals 5 are arranged on the lower side, and a plurality of wirings 13 extending from the plurality of wiring terminals 5. The flexible substrate 4 uses a flexible film, for example, a polyimide film having a thickness of 10 μm to 50 μm, and the wiring terminal 5 and the wiring 13 use a copper foil having a thickness of several μm to 20 μm. Further, the surfaces of the copper foil and the flexible film other than the wiring terminals 5 are covered with an insulating protective film having a thickness of 10 μm to 50 μm.

  Next, in the arranging step S2, as shown in FIG. 2B, the plurality of electrode terminals 3 and the plurality of wiring terminals 5 are opposed to each other with an anisotropic conductive sheet 6 interposed therebetween, and the flexible substrate 4 is moved to the head. Place on chip 2. The anisotropic conductive sheet 6 is made of a thermosetting resin having a thickness of about 30 μm, and conductive particles, for example, Ni particles are dispersed therein. Here, the method of electrically connecting the electrode terminal 3 and the wiring terminal 5 with the anisotropic conductive sheet 6 interposed between the electrode terminal 3 and the wiring terminal 5 is used. However, the present invention is not limited to this embodiment. I can't. For example, an anisotropic conductive paste obtained by diffusing conductive particles in a resin without using a film is interposed between the electrode terminal 3 and the wiring terminal 5 and applied with heat, whereby the electrode terminal 3 and the wiring terminal are applied. It is also possible to electrically connect 5.

  Next, in the temporary crimping step S3, as shown in FIGS. 3A and 3B, the vicinity of both ends in the reference direction K in which the wiring terminals 5 in the terminal region TR are arranged is thermocompression bonded to the flexible substrate 4 and the head chip. 2 is fixed. Specifically, the heated crimping head is brought into contact with the vicinity of both ends of the terminal region TR of the flexible substrate 4, and the vicinity of both ends of the terminal region TR is fixed to the head chip 2. The heating temperature is 260 ° C to 350 ° C, preferably 290 ° C to 310 ° C, and the heating time is about 10 seconds. This fixed region is represented by a stippling as a fixed region KR. Note that the fixed region KR in the present embodiment is a position where the electrode terminal 3 and the wiring terminal 5 are not formed in the vicinity of both ends of the terminal region TR (see FIGS. 3 and 4). By doing in this way, the flexible substrate 4 can be simply fixed without bonding terminals together.

  Next, in the main crimping step S4, as shown in FIG. 4, the flexible substrate 4 is thermocompression bonded to the head chip 2 to electrically connect the plurality of electrode terminals 3 and the plurality of wiring terminals 5, respectively. Specifically, the flexible substrate 4 in the main press bonding region HR between the two fixed regions KR is pressed against the head chip 2 while being heated by the press bonding head 14. The anisotropic conductive sheet 6 electrically connects the electrode terminal 3 and the wiring terminal 5 that are opposed to the conductive particles that are crushed and dispersed inside, and bonds the flexible substrate 4 and the head chip 2 together. At this time, even when there is a difference in thermal expansion between the flexible substrate 4 and the head chip 2, the positional deviation in the reference direction K between the electrode terminal 3 and the wiring terminal 5 is not integrated on one side or the other side of the terminal region TR. . As a result, the positional deviation between the electrode terminal 3 and the wiring terminal 5 is reduced, and electrical connection can be reliably performed. The heating temperature at the time of thermocompression bonding is 200 ° C. to 260 ° C., and the heating time is about 1 minute.

  Here, thermocompression bonding is performed so that there is no gap between the crimping head 14 and the two fixed regions KR. That is, in the main press-bonding step S4, the region between the fixed regions KR and in contact with the fixed region KR (the main press-bonded region HR) is subjected to thermocompression bonding. If there is a gap between the crimping head 14 and the fixed region KR, the expansion and contraction due to the difference in thermal expansion between the head chip 2 and the flexible substrate 4 is reduced to this gap, and a positional deviation occurs between the electrode terminal 3 and the wiring terminal 5. It tends to occur. Therefore, the width of the crimping head 14 in the reference direction K has a width between at least two fixed regions KR. Moreover, it is preferable that the heating temperature in the main press-bonding step S4 is lower than the heating temperature in the temporary press-bonding step S3 to prevent the fixing effect from being lowered.

  In addition, after performing alignment between the flexible substrate 4 and the head chip 2 in the arrangement step S2 of the present embodiment, a temporary fixing step of temporarily fixing the flexible substrate 4 and the head chip 2 by heating the terminal region TR. Can be included. Specifically, the alignment between the flexible substrate 4 and the head chip 2 is performed with the anisotropic conductive sheet 6 interposed and the plurality of electrode terminals 3 and the plurality of wiring terminals 5 facing each other. Next, a temporary fixing step of temporarily fixing a plurality of portions of the terminal region TR at a low temperature, for example, at a temperature of about 100 ° C. is performed. For example, using a heated soldering iron, the flexible substrate 4 is temporarily fixed to the head chip 2 by tracing a plurality of portions of the terminal region TR or a part or all of the terminal region TR in a straight line. In this way, by temporarily fixing the flexible substrate 4 and the head chip 2 at a relatively low temperature, even if a positional displacement occurs between the flexible substrate 4 and the head chip 2 later, the positional displacement is corrected by reheating. can do.

  In the present embodiment, the vicinity of both ends in the reference direction K of the terminal region TR is fixed in the temporary crimping step S3. However, in addition to this, other portions may be fixed. For example, in the temporary crimping step S3, in addition to the vicinity of both ends in the reference direction K of the terminal region TR, the vicinity of the center in the reference direction K of the terminal region TR and other portions may be fixed. This is particularly effective when the number of terminals included in the terminal region TR is large or when the terminal region TR is long in the reference direction K.

  Further, the liquid jet head manufactured by the manufacturing method of the present invention is not limited to the edge shoot type that discharges droplets in the vertical direction of the front end surface Ta of the head chip 2, but in the vertical direction of the lower surface DS of the head chip 2. A side chute type for discharging droplets may also be used.

(Second embodiment)
FIG. 5 is an explanatory diagram of the method of manufacturing the liquid jet head according to the second embodiment of the present invention. Fig.5 (a) is explanatory drawing of this crimping | compression-bonding process S4, FIG.5 (b) is a plane schematic diagram. In FIG.5 (b), the fixed area | region KR is represented by stippling, and this crimping | compression-bonding area | region HR is represented by white. A different point from the first embodiment is the main press-bonding step S4, and the preparation step S1 to the temporary press-bonding step S3 are the same as those in the first embodiment, and the description thereof is omitted. The same portions or portions having the same function are denoted by the same reference numerals.

  As shown in FIG. 5, in the main compression bonding step S <b> 4, a part of the fixed region KR is overlapped and thermocompression bonded. That is, in the main press-bonding step S4, thermocompression bonding is performed between the two fixed regions KR, and a part of each of the two fixed regions KR is overlapped and thermocompression bonded. That is, there is no room for a gap to be present between the two fixed regions KR and the region where the main press bonding is performed. As a result, the positional deviation between the electrode terminal 3 and the wiring terminal 5 is reduced, and the electrical connection between the electrode terminal 3 and the wiring terminal 5 can be more reliably performed. In addition, alignment of the crimping head 14 with respect to the flexible substrate 4 in the reference direction K is facilitated.

  In the main crimping step S4, when the crimping head 14 is thermocompression bonded over the two fixed regions KR, the anisotropic conductive sheet 6 in the fixed region KR is remelted, and the flexible substrate 4 and the head chip 2 are bonded. Cause misalignment. Therefore, the entire fixing region KR is not overlapped, but a part of the fixing region KR is overlapped and thermocompression bonded. The heating temperature and heating time in the temporary pressure bonding step S3 and the main pressure bonding step S4 are the same as those in the first embodiment. Here, in order to maintain the fixed state of the flexible substrate 4 and the head chip 2 in the fixing region KR, it is preferable that the heating temperature in the temporary press-bonding step S3 is higher than the heating temperature in the main press-bonding step S4. When the heating temperature in the main crimping step S4 is the same as the heating temperature in the temporary crimping step S3 or higher than the heating temperature in the temporary crimping step S3, a part of the anisotropic conductive sheet 6 in the fixed region KR is re-applied in the main crimping step S4. It melts and the fixing effect decreases.

  In the present embodiment, the fixed region KR does not include the wiring terminal 5 or the electrode terminal 3, but instead, the wiring terminal 5 or the electrode terminal 3 located at the end of the terminal region TR is used as the fixed region KR. Can be included. Even in this case, in the main crimping step S4, the wiring terminals 5 and the electrode terminals 3 included in the fixed region KR are thermocompression bonded and electrically connected. That is, the wiring terminals 5 and the electrode terminals 3 included in the fixed region KR may be included in the main crimping region HR.

(Third embodiment)
FIG. 6 is an explanatory diagram of a method for manufacturing a liquid jet head according to the third embodiment of the present invention. 6A is a schematic perspective view of the head chip 2 and the flexible substrate 4 in the placement step S2, and FIG. 6B is a schematic cross-sectional view of the portion BB in the temporary press-bonding step S3. (C) is a cross-sectional schematic diagram of the part BB in the main press-bonding step S4. The difference from the first and second embodiments is that the flexible substrate 4 is fixed to the side surfaces SSa and SSb of the head chip 2 in the temporary pressure bonding step S3. The same portions or portions having the same function are denoted by the same reference numerals.

  First, in the preparation step S1, a head chip 2 in which a plurality of electrode terminals 3 are arranged and a flexible substrate 4 having a terminal region TR in which a plurality of wiring terminals 5 are arranged are prepared. Next, as shown in FIG. 6A, in the placement step S2, the plurality of electrode terminals 3 and the plurality of wiring terminals 5 are opposed to each other with the anisotropic conductive sheet 6 interposed therebetween, and the flexible substrate 4 is moved to the head. Place on chip 2. In this case, the flexible substrate 4 near at least one end of the terminal region TR is bent and disposed on the side surfaces SSa and SSb of the head chip 2 (actuator substrate 10). It is the same as that of 1st embodiment that a temporary fixing process can be included in arrangement | positioning process S2. In the present embodiment, the bent portions BNa and BNb obtained by bending the flexible substrate 4 near both ends of the terminal region TR are arranged on the side surfaces SSa and SSb of the head chip 2 (actuator substrate 10).

  Next, as shown in FIG. 6B, in the temporary crimping step S3, the bent portions BNa and BNb of the flexible substrate 4 near both ends of the terminal region TR are thermocompression bonded to both side surfaces SSa and SSb of the head chip 2, respectively. And fix. Specifically, for example, a crimping head heated to 300 ° C. is brought into contact with the bent portions BNa and BNb and fixed. At this time, both bent portions BNa and BNb are fixed to both side surfaces SSa and SSb of the head chip 2, respectively, and the upper surface US of the head chip 2 and each corner portion of the both side surfaces SSa and SSb and both bent portions BNa and BNb of the head chip 2 are fixed. Securely fix both bent corners.

  Next, as shown in FIG. 6C, the flexible substrate 4 and the head chip 2 are thermocompression bonded to electrically connect the plurality of electrode terminals 3 and the plurality of wiring terminals 5, respectively. Specifically, the pressure bonding head 14 is brought into contact with the flexible substrate 4 on the upper surface US side of the head chip 2 and thermocompression bonded. The crimping head 14 has the same width as the width in the reference direction K of the head chip 2 (actuator substrate 10) or a width wider than the width in the reference direction K. Therefore, the region to be thermocompression-bonded and the fixed region KR are continuous in the main crimping step S4, and no gap is generated. Will not be accumulated. As a result, the positional deviation between the electrode terminal 3 and the wiring terminal 5 is reduced, and electrical connection can be reliably performed. In addition, the heating temperature, heating time, etc. in the temporary press-bonding step S3 and the main press-bonding step S4 are the same as those in the first embodiment.

  In the present embodiment, since the flexible substrate 4 is fixed to both side surfaces SSa and SSb of the head chip 2, there is no need to provide the fixing region KR on the upper surface US of the head chip 2, and the upper surface US of the head chip 2 is widely used. Thus, the electrode terminal 3 can be arranged.

(Fourth embodiment)
FIG. 7 is an explanatory diagram of the method of manufacturing the liquid jet head according to the fourth embodiment of the present invention. FIG. 7A is a schematic plan view of the flexible substrate 4, and FIG. 7B is a schematic cross-sectional view for explaining the main crimping step S4. The difference from the first to third embodiments is that the surface opposite to the surface on which the wiring terminals 5 are arranged corresponds to the terminal region TR of the flexible substrate 4 and protrudes in a convex shape. Other configurations are the same as those of the other embodiments. The same portions or portions having the same function are denoted by the same reference numerals.

  As shown in FIG. 7A, the flexible substrate 4 has a convex region 7 corresponding to the terminal region TR and protruding from the surface opposite to the surface on which the wiring terminals 5 are arranged. Then, in the main crimping step S4, as shown in FIG. 7B, the head chip 2 and the flexible substrate 4 are thermocompression bonded with the crimping head 14 in contact with the upper end surface of the convex region 7, and a plurality of electrode terminals 3 and the plurality of wiring terminals 5 are electrically connected to each other.

  Here, the convex region 7 is arranged so as to be in contact with the two fixed regions KR or a part of the two fixed regions KR. If the width of the crimping head 14 is larger than the width of the convex region 7 in the reference direction K, even if the crimping head 14 is slightly displaced in the reference direction K with respect to the head chip 2 or the flexible substrate 4, The crimping head 14 is always in contact with the convex region 7, and the crimping head 14 and the flexible substrate 4 can be easily aligned in the final crimping step S <b> 4. In addition, the convex area | region 7 may form the area | region which changed thickness in the flexible substrate 4 previously, affixing a convex member between preparation process S1-temporary pressure bonding process S3, and convex shape Region 7 may be formed.

(Fifth embodiment)
FIG. 8 is an explanatory diagram of a method of manufacturing a liquid jet head according to the fifth embodiment of the present invention. FIG. 8A is an explanatory view of the preparation step S1 and the placement step S2, and FIG. 8B is an explanatory view of the provisional pressure bonding step S3 and the main pressure bonding step S4. The same portions or portions having the same function are denoted by the same reference numerals.

  As shown in FIG. 8A, the head chip 2 prepared in the preparation step S1 includes an actuator substrate 10, a cover plate 11 joined to the upper surface US of the actuator substrate 10, and the front end surfaces of the actuator substrate 10 and the cover plate 11. And a nozzle plate 12 bonded to Ta. The actuator substrate 10 includes, on its upper surface US, ejection grooves 10a and non-ejection grooves 10b that are partitioned by side walls 10c and are alternately arranged in the reference direction K. The ejection grooves 10 a and the non-ejection grooves 10 b have a depth that does not reach the lower surface DS of the actuator substrate 10. The non-ejection groove 10 b is a straight groove extending from the front end face Ta to the rear end face Tb of the actuator substrate 10. The discharge groove 10a opens in the front end face Ta of the actuator substrate 10, is cut up before reaching the rear end face Tb, and terminates at the upper surface US.

  The side wall 10c includes a drive electrode 10d on the side surface on the ejection groove 10a side and a drive electrode 10e on the side surface on the non-ejection groove 10b side. The drive electrodes 10d and 10e are indicated by hatching. Each drive electrode 10d, 10e has a width that is approximately ½ of each groove from the upper surface US. The actuator substrate 10 is an upper surface US on the rear end surface Tb side, and includes an individual electrode terminal 3b between two adjacent non-ejection grooves 10b. The actuator substrate 10 includes a common electrode terminal 3a on the upper surface US on the front side of the individual electrode terminal 3b. The common electrode terminal 3a and the individual electrode terminal 3b are indicated by hatching. The actuator substrate 10 further includes a shallow groove 10f that is shallower than the non-ejection groove 10b between the common electrode terminal 3a and the individual electrode terminal 3b. The shallow groove 10f extends in the reference direction K of the upper surface US. The actuator substrate 10 includes a step surface 10g that is lower than the upper surface US at corners of the upper surface US and the rear end surface Tb. The common electrode terminal 3a is electrically connected to drive electrodes 10d installed on both side surfaces of the ejection groove 10a. The individual electrode terminal 3b is electrically connected to the drive electrode 10e installed on the side surface of the adjacent two non-ejection grooves 10b on the ejection groove 10a side.

  The cover plate 11 is joined to the upper surface US of the actuator substrate 10 so that the common electrode terminal 3a and the individual electrode terminal 3b are exposed. The cover plate 11 includes a liquid supply chamber 11a and a slit 11b penetrating from the bottom surface of the liquid supply chamber 11a to the surface of the cover plate 11 on the actuator substrate 10 side. The slit 11b communicates with the rear side of the ejection groove 10a and does not communicate with the non-ejection groove 10b. Accordingly, the non-ejection groove 10b and the liquid supply chamber 11a do not communicate with each other. The nozzle plate 12 is bonded to the actuator substrate 10 and the front end face Ta of the cover plate 11. The nozzle plate 12 includes a nozzle 12a communicating with the discharge groove 10a.

  Accordingly, the head chip 2 according to the fifth embodiment includes two electrode terminal arrays, that is, a plurality of common electrode terminals 3 a arranged in the reference direction K and a plurality of individual electrode terminals 3 b arranged in the reference direction K.

  As shown in FIG. 8A, the flexible substrate 4 prepared in the preparation step S1 corresponds to each of the plurality of common electrode terminals 3a, and includes a plurality of common wiring terminals 5a arranged in the reference direction K and a plurality of individual electrodes. Corresponding to each of the electrode terminals 3b, two wiring terminal rows including a plurality of individual wiring terminals 5b arranged in the reference direction K are provided. The flexible substrate 4 further includes a common wiring 13a electrically connected to each common wiring terminal 5a between two wiring terminal rows, and a plurality of individual wirings 13b electrically connected to each of the plurality of individual wiring terminals 5b. Is provided. The common wiring terminal 5a, the individual wiring terminal 5b, the common wiring 13a, and the individual wiring 13b are shown in white. Therefore, the flexible substrate 4 of the present embodiment includes two wiring terminal rows arranged in the reference direction K, and a common wiring 13a extending in the reference direction K between the two wiring terminal rows. Here, two wiring terminal rows arranged in the reference direction K constitute a terminal region TR. The materials and thicknesses of the actuator substrate 10 and the flexible substrate 4 are the same as in the first embodiment.

  FIG. 8B is a schematic plan view showing a part of the state in which the flexible substrate 4 is arranged on the head chip 2. The flexible substrate 4 includes common wiring terminals 5a, individual wiring terminals 5b, and common wirings 13a in the terminal region TR.

  In the placement step S2, the plurality of common electrode terminals 3a and the plurality of common wiring terminals 5a are opposed to each other, and the plurality of individual electrode terminals 3b and the plurality of individual wiring terminals 5b are opposed to each other with the anisotropic conductive sheet 6 interposed therebetween. Thus, the flexible substrate 4 is arranged on the head chip 2. The common wiring 13a is located in the opening of the shallow groove 10f in a region between the wiring terminal row of the common wiring terminals 5a and the wiring terminal row of the individual wiring terminals 5b. Therefore, even after the common electrode terminal 3a and the common wiring terminal 5a and the individual electrode terminal 3b and the individual wiring terminal 5b are electrically connected in the main crimping step S4, both side surfaces of the common wiring 13a and the non-ejection groove 10b. There is no electrical short circuit with the drive electrode 10e positioned at the position. In addition, the temporary fixing process can be included in arrangement | positioning process S2. That is, after the alignment between the flexible substrate 4 and the head chip 2 is performed, the terminal region TR is heated to temporarily fix the flexible substrate 4 and the head chip 2. For example, using a heated soldering iron, the flexible substrate 4 is temporarily fixed to the head chip 2 by tracing a plurality of portions of the terminal region TR or a part or all of the terminal region TR in a straight line.

  In the temporary crimping step S3, as shown in FIG. 8B, the flexible substrate 4 is attached to the head chip 2 by thermocompression bonding in the vicinity of both ends in the reference direction K of the terminal region TR in which the common wiring terminals 5a and the individual wiring terminals 5b are arranged. (Fixed region KR represented by a two-dot chain line). Here, the fixed region KR is a region on the outer peripheral side with respect to the non-ejection groove 10b located at the end of the groove row composed of the ejection groove 10a and the non-ejection groove 10b. The fixed region KR is located on the outer peripheral side of the non-ejection groove 10b located at the end of the groove row and between the non-ejection groove 10b located at the end of the groove row and the non-ejection groove 10b located next thereto. May be added. In the temporary press-bonding step S3, the heating temperature and the heating time when the flexible substrate 4 is thermo-bonded to the head chip 2 are the same as those in the first embodiment.

  Next, in the main crimping step S4, the flexible substrate 4 in the main crimping region HR (represented by a one-dot chain line) shown in FIG. The common wiring terminal 5a is electrically connected to the plurality of individual electrode terminals 3b and the plurality of individual wiring terminals 5b. In the main press bonding step S4, the temperature at which the flexible substrate 4 is thermocompression bonded to the head chip 2 is preferably lower than the temperature of the thermocompression bonding in the temporary press bonding step S3. Here, when the fixed region KR is located in a region on the outer peripheral side of the non-ejection groove 10b located at the end of the groove row, the main crimping step S4 is performed in the fixed region located in the region on the outer peripheral side of the non-ejection groove 10b. A part of KR is overlapped and thermocompression bonded. That is, thermocompression bonding is performed so that a part of the fixed region KR overlaps with the main pressure bonding region HR.

  When the fixing region KR extends from the outer peripheral side of the actuator substrate 10 of the non-ejection groove 10b located at the end of the groove row to the ejection groove 10a adjacent to the non-ejection groove 10b, the main crimping step S4 Thermocompression bonding can be performed on a part of the region KR. When the fixed region KR extends between the non-ejection groove 10b located at the end of the groove row and the ejection groove 10a adjacent to the non-ejection groove 10b, the fixed region KR is between the non-ejection groove 10b and the ejection groove 10a. The region may be subjected to thermocompression bonding in the main compression bonding step S4. In other words, in the main press-bonding step S4, a part of the fixed region KR excluding the region where the non-ejection groove 10b opens to the upper surface US is overlapped and thermocompression bonded. In the main crimping step S4, the heating temperature and the heating time when the flexible substrate 4 is thermocompression bonded to the head chip 2 are the same as those in the first embodiment.

  In the present embodiment, the common wiring 13a continuously extends in the reference direction K between the two wiring terminal rows of the common wiring terminal 5a and the individual wiring terminal 5b of the flexible substrate 4. The common wiring 13a is made of a conductive material such as copper foil, and has a larger linear expansion coefficient than the flexible substrate 4 made of a synthetic resin such as a polyimide film. Therefore, when the flexible substrate 4 is thermocompression bonded to the head chip 2, the displacement of the wiring terminal 5 with respect to the electrode terminal 3 further increases. However, as in the present invention, in the temporary crimping step S3, the vicinity of both ends of the terminal region TR of the flexible substrate 4 is fixed to the head chip 2, and then in the final crimping step S4, between the two fixed regions KR or two By subjecting each part of the fixed region KR to overlap-bonding, the positional deviation between the electrode terminal 3 and the wiring terminal 5 is reduced, and the electrical connection between the electrode terminal 3 and the wiring terminal 5 is ensured. Can be done.

(Modification)
FIG. 9 is a schematic cross-sectional view in the ejection groove direction showing a modification of the fifth embodiment of the present invention. The same portions or portions having the same function are denoted by the same reference numerals. In the fifth embodiment, the common wiring 13a is installed on the same surface as the common wiring terminal 5a and the individual wiring terminal 5b. In addition to this, the upper common wiring 13c is arranged on a different surface from the common wiring terminal 5a and the individual wiring terminal 5b. Install. Then, the common wiring 13 a and the upper common wiring 13 c are electrically connected by the through electrode 8. As a result, the common wiring 13a and the upper common wiring 13c are arranged in parallel, and a large current can be passed. The other configurations of the actuator substrate 10 and the flexible substrate 4 are the same as those in the fifth embodiment, and thus the description thereof is omitted.

2 Head chip 3 Electrode terminal, 3a Common electrode terminal, 3b Individual electrode terminal 4 Flexible substrate 5 Wiring terminal, 5a Common wiring terminal, 5b Individual wiring terminal 6 Anisotropic conductive sheet 7 Convex region 8 Through electrode 10 Actuator substrate, 10a Discharge groove, 10b Non-discharge groove, 10c Side wall 10d Drive electrode, 10e Drive electrode, 10f Shallow groove, 10g Step surface 11 Cover plate, 11a Liquid supply chamber, 11b Slit 12 Nozzle plate, 12a Nozzle 13a Common wiring, 13b Individual wiring, 13c Upper common wiring 14 Crimp head Ta Front end surface, Tb Rear end surface, K Reference direction, KR fixing region, HR Main crimp region TR Terminal region, US upper surface, SS, SSa, SSb side surface, DS lower surface BN, BNa, BNb Bending portion

Claims (10)

Preparing a head chip in which a plurality of electrode terminals are arranged and a flexible substrate having a terminal region in which a plurality of wiring terminals are arranged;
A plurality of electrode terminals and a plurality of wiring terminals facing each other, and arranging the flexible substrate on the head chip; and
A temporary crimping step of fixing the flexible substrate and the head chip by thermocompression bonding in the vicinity of both ends of the terminal region in the direction in which the wiring terminals are arranged;
A liquid bonding head manufacturing method comprising: a main pressure bonding step of thermally connecting the flexible substrate to the head chip and electrically connecting the plurality of electrode terminals and the plurality of wiring terminals, respectively.   The positioning step includes a temporary fixing step of temporarily fixing the flexible substrate and the head chip by heating the terminal region after positioning between the flexible substrate and the head chip. Manufacturing method of liquid jet head of As an area fixed in the temporary crimping step,
The method of manufacturing a liquid jet head according to claim 1, wherein the main press-bonding step is performed by thermo-compression of a region between the fixed regions and in contact with the fixed region.   The method of manufacturing a liquid jet head according to claim 3, wherein the main press-bonding step performs thermo-compression by overlapping a part of the fixed region.   5. The method of manufacturing a liquid jet head according to claim 1, wherein a heating temperature in the temporary press-bonding step is higher than a heating temperature in the main press-bonding step. The arranging step arranges the flexible substrate in the vicinity of at least one end of the terminal region on a side surface of the head chip,
6. The method of manufacturing a liquid jet head according to claim 1, wherein the temporary pressing step fixes the flexible substrate in the vicinity of the end to the side surface of the head chip by thermocompression bonding. The flexible substrate has a convex region corresponding to the terminal region and protruding from the surface opposite to the surface on which the wiring terminals are arranged,
The method of manufacturing a liquid jet head according to claim 1, wherein the main press-bonding step includes thermocompression bonding of an upper end surface of the convex region. The electrode terminal includes a common electrode terminal and individual electrode terminals, the plurality of common electrode terminals and the plurality of individual electrode terminals are arranged in parallel,
The wiring terminals include common wiring terminals and individual wiring terminals, and the plurality of common wiring terminals and the plurality of individual wiring terminals are arranged in parallel,
The preparation step is a step of facing the plurality of common electrode terminals and the plurality of common wiring terminals, and the plurality of individual electrode terminals and the plurality of individual wiring terminals, respectively.
The main crimping step is a step of electrically connecting the plurality of common electrode terminals and the plurality of common wiring terminals, and the plurality of individual electrode terminals and the plurality of individual wiring terminals, respectively. The method for manufacturing a liquid jet head according to claim 7.   The liquid ejecting head according to claim 8, wherein the flexible substrate includes a common wire that is long in a direction in which the wiring terminals are arranged between the common wiring terminals and the individual wiring terminals in the terminal region. Method. A terminal region in which a plurality of wiring terminals are arranged;
A liquid ejecting head including a flexible substrate having a convex region corresponding to the terminal region and protruding from a surface opposite to a surface on which the wiring terminals are arranged.

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