JP4470458B2 - Method for manufacturing liquid discharge head - Google Patents

Description

  The present invention relates to a method for manufacturing a liquid discharge head used in an inkjet printer or the like. Specifically, the present invention relates to a method for manufacturing a liquid discharge head suitable for use in a line head at low cost and with high accuracy.

Conventionally, an ink jet printer has been known as an example of a liquid ejecting apparatus, and various techniques have been disclosed for a printer head (liquid ejecting head) of an ink jet printer.
For example, Patent Literature 1 and Patent Literature 2 disclose a technique for forming a line head by a plurality of head chips.
JP 2002-127427 A JP 2003-25579 A

  In the techniques of Patent Literature 1 and Patent Literature 2 described above, a large number of nozzles (ink ejection ports) are provided in one nozzle forming member made of nickel formed by electroforming. A plurality of head chips are attached to the one nozzle forming member. Further, a head frame in which holes are formed so as to surround the attached head chip is bonded to the nozzle sheet, and the nozzle sheet is supported.

  Note that heating resistors are arranged on the head chip, and the head chip is attached to the nozzle sheet so that each heating resistor corresponds to each nozzle. An ink liquid chamber is provided between the heating resistor and the nozzle.

Also, a technique is known in which a plurality of print head dies 40 (head chips) are provided as one ink jet print head module 90, and the ink jet print head modules 90 can be connected and extended (for example, Patent Document 3 ( In particular, see FIG.
JP 2002-86695 A

  However, in the techniques of Patent Document 1 and Patent Document 2 described above, the nozzle forming member is formed with nozzles corresponding to all the head chips, and thus increases in size. There is a problem that it is required to affix the head chip in a state in which flatness is ensured, resulting in an increase in assembly cost.

On the other hand, in the technique of Patent Document 3, a line head can be formed by connecting a plurality of ink jet print head modules 90, so that productivity can be improved.
However, there is no mention of how to ensure the positional accuracy of the nozzle openings 472 between the plurality of print head dies 40. For example, if the nozzles of all the head chips are formed on one nozzle forming member as in Patent Document 1 and Patent Document 2, there is almost no relative displacement between the nozzles. On the other hand, when a plurality of print head dies 40 are arranged as in Patent Document 3, if a relative position shift occurs between the print head dies 40, a nozzle position shift occurs.

In the technique of Patent Document 3, there is no mention of how to ensure the flatness of the ink ejection surface between the plurality of print head dies 40.
Here, when ink is ejected accurately and perpendicularly to the ink landing surface of the recording medium, even if there is a slight misalignment on the formation surface of each nozzle opening 472, there is no significant effect on the print quality. For example, when the ink ejection direction is not completely perpendicular to the ink landing surface of the recording medium, the ink landing position changes if the positions of the formation surfaces of all the nozzle openings 472 do not match. .

In particular, the applicant of the present application has disclosed the undisclosed prior application technologies of Japanese Patent Application 2003-037343, Japanese Patent Application 2002-360408, Japanese Patent Application 2003-55236, and the like in a plurality of directions. We have already proposed a technique that makes it possible to make high-quality printing by making the landing position of droplets inconspicuous by making it variable.
As described above, when using a technique for positively changing the discharge direction of the droplets discharged from the nozzle, the position accuracy of the nozzle surface, that is, the formation surface of the nozzle opening 472 in Patent Document 3, is high. Required.

  Furthermore, in the technique of Patent Document 3, when a plurality of ink jet print head modules 90 are connected and extended, the ink jet print head module 90 is positioned by the reference body 70. However, this method has a problem that the manufacturing cost increases because the reference body 70 itself must be processed and arranged with high accuracy.

  Therefore, the problem to be solved by the present invention is to manufacture a liquid discharge head suitable for use in a line head at low cost and with high accuracy.

The present invention solves the above-described problems by the following means.
A first aspect of the present invention is a nozzle having a head chip in which a plurality of energy generating elements are arranged in one direction at regular intervals, and a nozzle row in which a plurality of nozzles for discharging droplets are arranged. A liquid chamber forming member for forming a liquid chamber between each of the energy generating elements and each of the nozzles, the sheet being stacked between the sheet and the surface of the head chip on which the energy generating elements are formed and the nozzle sheet; A hole for supporting the nozzle sheet by being bonded to one surface of the nozzle sheet and arranging the head chip therein, and when the head chip is arranged in the region, A module frame having a head chip arrangement hole in which the nozzle row is positioned at a position facing each energy generating element of the head chip, and the energy The raw element forms a plurality of head modules for discharging the liquid in the liquid chamber from the nozzles, and a head module arrangement hole for arranging the plurality of head modules arranged in series inside the head module. A method of manufacturing a liquid discharge head comprising a head frame joined to each of the head modules arranged in an arrangement hole, the first step of joining the module frame to one surface of the nozzle sheet, The nozzle is arranged at a position facing each energy generating element of the head chip when the head chip is arranged in the area of the head chip arrangement hole in the nozzle sheet in the area of the head chip arrangement hole. A second step of forming the nozzle row and generating each energy of the head chip The head chip provided with the liquid chamber forming member in the head chip placement hole so that the nozzle and each nozzle formed in the nozzle sheet in the region of the head chip placement hole face each other. A plurality of the head modules are formed by a step including a third step of arranging and bonding, and the pressure-sensitive adhesive layer of the holding plate provided with a plurality of the head modules and a flat surface having at least a surface made of the pressure-sensitive adhesive layer. A fourth step of positioning the head modules by the adhesive force of the pressure-sensitive adhesive layer and positioning the head modules in series, and from above the plurality of head modules arranged by the fourth step By mounting a head frame, a plurality of the head modules arranged in series are connected to the head module of the head frame. A fifth step of bonding the head frame and each of the head modules, and after bonding in the fifth step, the adhesive force of the pressure-sensitive adhesive layer is lost, and the head frame And a sixth step of separating the bonded head module from the pressure-sensitive adhesive layer.

  In the said invention, a nozzle sheet | seat and a module frame are joined (1st process). A head chip arrangement hole is formed in the module frame, and a nozzle row is formed on the nozzle sheet in the head chip arrangement hole (second step). Next, the head chip provided with the liquid chamber forming member is arranged in the head chip arrangement hole and bonded so that the energy generating element of the head chip and the nozzle face each other (third step).

The droplet ejection surface of the head module formed in this way (the surface opposite to the surface of the nozzle sheet bonded to the module frame) is placed on the adhesive layer provided on the holding plate, and a plurality of The head modules are positioned in a state where they are arranged in series (fourth step). Here, since the adhesive layer is formed on the holding plate, each head module is held by the adhesive force. Therefore, once the head module is positioned on the adhesive layer of the holding plate, the position is held. The plurality of head modules arranged in series positioned as described above are arranged in the head module arrangement hole of the head frame, and the module frame and the head frame of each head module are joined (fifth step). .
Next, the adhesive force of the pressure-sensitive adhesive layer is lost, and the head frame and the head module joined together are separated from the pressure-sensitive adhesive layer (sixth step).

The energy generating element of the present invention may be a heating resistor such as a heater, a piezoelectric element such as a piezo element, MEMS, or the like, but the heating resistor 22 corresponds in the following embodiments. In addition, the liquid chamber forming member of the present invention corresponds to the barrier layer 12 in the embodiment. Furthermore, in the embodiment, four head chip arrangement holes 11 b are formed in the module frame 11, and four head chips 20 are provided in one head module 10. Then, four head modules 10 are connected in series to make the length of the A4 plate, and four rows are provided, and Y (yellow), M (magenta), C (cyan), and K (black) are provided. The liquid discharge head 1 which is a four-color color line head is formed.
Moreover, the adhesive layer formed in the holding | maintenance plate of this invention lose | disappears the adhesive force by irradiation of an ultraviolet-ray in embodiment, and is provided in the adhesive sheet C3.

According to the present invention, since only the head chip is adhered to the nozzle sheet in the head chip arrangement hole, unnecessary stress is hardly applied to the nozzle surface, and the flatness and positional accuracy of the nozzle surface are easily secured. be able to.
In addition, when a plurality of head modules arranged in series is incorporated into the head module placement hole of the head frame, each head module is held by the adhesive force of the adhesive layer. Each head module can be reliably positioned before and after joining.

  Furthermore, after the head frame and the head module are joined, the adhesive strength of the adhesive layer can be lost, so that the joint of the head frame and the head module is separated from the adhesive layer without applying a load. be able to. Therefore, the liquid discharge head using the head module can be easily manufactured with high accuracy and at low cost.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
In addition, the following terms in this specification and claims are used in the following meanings.
“Bonding” means permanent bonding not premised on separation (or peeling), (1) bonding members through an adhesive, and (2) applying thermocompression bonding and ultrasonic vibration. This includes both joining (bonding) without using an adhesive (without an adhesive between the two members) by ultrasonic bonding or welding.
In addition, “adhesion” is a kind of the above-mentioned joining, and means that members are bonded (bonded) via an adhesive (with an adhesive interposed between the members), and separated (or peeled). ) For the purpose of permanent connection without premise.

  Furthermore, “adhesion” is a term for permanent adhesion, refers to temporary adhesion on the premise of separation (or peeling) after bonding, and bonds (bonds) members together using an adhesive. That means. Moreover, as an adhesive used for adhesion, for example, (1) It has weak adhesive force, and after adhering members, it can separate members adhered by applying separation (peeling) force And (2) those capable of separating the adhered members by irradiating ultraviolet rays or applying thermal energy so that the adhesive force of the adhesive is lost. Some pressure-sensitive adhesives are permanently bonded by post-treatment.

  FIG. 1 is a plan view showing a liquid discharge head 1 according to an embodiment of the present invention, and a side view (cross-sectional view) in the direction of arrow X in this plan view. FIG. 2 is a side cross-sectional view showing the head chip 20 mounted in the liquid ejection head 1 and the surrounding structure, and a plan view seen from the bottom.

  The liquid discharge head 1 is used as a head mounted on a liquid discharge apparatus (in this embodiment, a color line inkjet printer). As shown in FIG. 1, the liquid ejection head 1 includes a head frame 2, a printed circuit board 3, and a plurality of head modules 10. In the plan view of FIG. 1, four head modules 10 are connected in series in the longitudinal direction, and four head modules 10 connected in series are provided in four rows. One head is printed by four head modules 10 connected in series. In this embodiment, a liquid discharge head 1 (line head) of four colors (Y, M, C, and K) is formed. ing.

Each head module 10 is provided with four head chips 20. FIG. 2 shows one head chip 20.
The head chip 20 includes a semiconductor substrate 21 made of silicon or the like, and a heating resistor 22 (corresponding to an energy generating element in the present invention) deposited on one surface of the semiconductor substrate 21. A connection pad 23 made of aluminum is formed on the edge of the semiconductor substrate 21 on the same side as the surface on which the heating resistor 22 is formed and opposite to the edge on which the heating resistor 22 is formed. . The heating resistor 22 and the connection pad 23 are connected via a conductor portion (not shown) formed on the semiconductor substrate 21.

  The side of the head chip 20 on which the heating resistor 22 is formed is laminated on the nozzle sheet 13 via the barrier layer 12 (corresponding to the liquid chamber forming member in the present invention). The barrier layer 12 is for forming the side wall of the ink liquid chamber 14 and is made of, for example, a photosensitive cyclized rubber resist or an exposure-curing dry film resist, and the heating resistance of the semiconductor substrate 21 of the head chip 20. After the body 22 is stacked on the entire surface, unnecessary portions are removed by a photolithography process.

  In FIG. 2, the plan view shows one heating resistor 22 and the barrier layer 12 provided around the heating resistor 22. The barrier layer 12 is formed in a substantially concave shape when viewed in plan so as to surround the vicinity of the three sides of the heating resistor 22.

  Furthermore, the nozzle sheet 13 is formed with a plurality of nozzles 13a. For example, the nozzle sheet 13 is formed by an electroforming technique using nickel, so that the position of the nozzle 13a matches the position of the heating resistor 22, that is, the nozzle 13a. More specifically, the center axis of the nozzle 13a and the center of the heating resistor 22 coincide with each other so as to face the heating resistor 22 (see the plan view of FIG. 2). The barrier layer 12 is bonded.

  The ink liquid chamber 14 is composed of the semiconductor substrate 21, the barrier layer 12, and the nozzle sheet 13 so as to surround the heating resistor 22. The ink liquid chamber 14 is filled with ink to be ejected, and ink is applied when ink is ejected. It becomes a pressure chamber. The surface of the semiconductor substrate 21 on which the heat generating resistor 22 is formed constitutes the bottom wall of the ink liquid chamber 14, and the portion of the barrier layer 12 surrounding the heat generating resistor 22 in a substantially concave shape forms the side wall of the ink liquid chamber 14. The nozzle sheet 13 constitutes the top wall of the ink liquid chamber 14. The ink liquid chamber 14 communicates with a flow path 16 formed by a gap between the head module 11 and the semiconductor substrate 21 as shown in the plan view of FIG.

  The one head chip 20 is usually provided with heating resistors 22 in units of 100, and each of the heating resistors 22 is uniquely selected by a command from a control unit (not shown) of the printer. Ink in the ink liquid chamber 14 corresponding to the heating resistor 22 can be ejected from the nozzle 13 a facing the ink liquid chamber 14.

  That is, when the ink liquid chamber 14 is filled with ink, the heating resistor 22 is rapidly heated by passing a pulse current through the heating resistor 22 for a short time, for example, 1 to 3 μsec. As a result, a gas-phase ink bubble is generated at a portion in contact with the heating resistor 22, and a certain volume of ink is pushed away (the ink boils) due to the expansion of the ink bubble. As a result, a volume of ink equivalent to the pushed ink in the portion in contact with the nozzle 13a is ejected from the nozzle 13a as an ink droplet. The droplets are landed on the photographic paper to form dots (pixels).

Next, a more detailed structure and manufacturing process of the head module 10 will be described.
FIG. 3 is a plan view and a front view showing one head module 10. The head module 10 according to this embodiment includes four head chips 20 arranged inside, a module frame 11, a nozzle sheet 13, and a buffer tank 15.

  FIG. 4 is a plan view showing the nozzle sheet 13 and the module frame 11 in an exploded manner. The module frame 11 is formed in a substantially rectangular shape when viewed in a plan view, and has engaging portions 11a cut out in a substantially L shape on both left and right ends. As is apparent from FIG. 4, when the nozzle sheet 13 and the module frame 11 are overlapped, the shapes of both are formed so as to substantially overlap except for the wiring pattern portion 13 b of the nozzle sheet 13.

  The wiring pattern portion 13b is a portion of the nozzle sheet 13 that does not overlap the module frame 11, and is formed by forming a so-called sandwich structure in which a copper foil is sandwiched from both sides with polyimide or the like. As shown in FIG. 12 to be described later, the wiring pattern portion 13b is wired up to an area in each head chip arrangement hole 11b, and when the head chip 20 is arranged in the head chip arrangement hole 11b, the head chip is arranged. It is formed so that electrical connection with 20 is possible.

  The module frame 11 is formed of invar steel, alumina ceramics, or the like having a thickness of about 0.5 mm. In this embodiment, substantially rectangular head chip arrangement holes 11b are formed at four locations. . The head chip placement hole 11b has a hole shape slightly larger than the outer shape of the head chip 20, so that the head chip 20 can be completely placed inside.

  FIG. 5 is a plan view and a front view showing a state in which the module frame 11 is disposed on the nozzle sheet 13. In this embodiment, it joins by hot-pressing both by hot press (1st process). Thereby, the module frame 11 substantially overlaps the area of the nozzle sheet 13 excluding the wiring pattern portion 13b. In other words, only the region where the wiring pattern portion 13 b of the nozzle sheet 13 is formed does not overlap the region of the module frame 11. Further, the nozzle sheet 13 located below the head chip arrangement hole 11b can be seen.

  The module frame 11 and the nozzle sheet 13 are joined at the highest temperature (for example, about 150 ° C.) in the manufacturing process of the head module 10 and the liquid ejection head 1. When the module frame 11 and the nozzle sheet 13 are compared, the nozzle sheet 13 has a larger linear expansion coefficient (easily expands and contracts due to temperature changes). Below this temperature, the nozzle sheet 13 is stretched by the module frame 11. That is, the expansion and contraction due to the temperature change of the nozzle sheet 13 is governed by the module frame 11 after the nozzle sheet 13 and the module frame 11 are joined.

  Therefore, in order to ensure the rigidity of the module frame 11 as much as possible, it is preferable that the opening area of the head chip arrangement hole 11b of the module frame 11 is minimized. That is, after the placement of the head chip 20 in the head chip placement hole 11b, a flow path 16 is formed between the common liquid flow path 15a in the buffer tank 15 described later and the ink liquid chamber 14, and the nozzle sheet 13 is also formed. It is preferable to set the opening area to a minimum, on the condition that the positional deviation when the head chip 20 is arranged in accordance with the nozzle 13a formed in the above can be absorbed.

  Subsequently, a nozzle 13a row in which a number of nozzles 13a opposite to the number of heating resistors 22 in one head chip 20 are aligned in one direction with respect to the nozzle sheet 13 in the area of the head chip arrangement hole 11b. Form (second step). FIG. 6 is a plan view showing a state in which the nozzle 13a row is formed on the nozzle sheet 13 in the head chip arrangement hole 11b.

The nozzle 13a is formed by an excimer laser. Further, since the nozzle 13a formed by the laser beam is tapered, the laser beam is irradiated from the module frame 11 side to form the nozzle 13a. As a result, the nozzle 13a becomes a hole having a taper so that the opening diameter gradually decreases as it approaches the ink ejection surface (the outer surface of the nozzle sheet 13).
Further, the pitch between the nozzles 13a of the nozzle 13a row formed in each head chip arrangement hole 11b is the same as the arrangement pitch of the heating resistors 22 of the head chip 20 (in the case of the head module 10 having a resolution of 600 dpi, And about 42.3 μm).

  Furthermore, as shown in FIG. 6, the nozzle 13a row in each head chip arrangement hole 11b is considered to be a line connecting the nozzles 13a row in each head chip arrangement hole 11b (a line passing through the center of each nozzle 13a). Sometimes, the line is formed on the center line side of the module frame 11 drawn parallel to the longitudinal direction of the module frame 11. Further, assuming that each head chip arrangement hole 11b is “N”, “N + 1”, “N + 2”, “N + 3” in order from the left side, the nozzles in the “N” -th and “N + 2” -th head chip arrangement holes 11b. The 13a row is formed so as to be aligned on a straight line parallel to the center line. The same applies to the “N + 1” th and “N + 3” th.

Therefore, the nozzles 13a in the adjacent head chip arrangement holes 11b, for example, the nozzles 13a in the “N” th and “N + 1” th head chip arrangement holes 11b are on two straight lines parallel to the center line. Align.
In this embodiment, four head chip arrangement holes 11b are formed for one module frame 11. However, even when more head chip arrangement holes 11b are formed than in this embodiment, the above relationship is satisfied. Like that.

  Next, as shown in FIG. 7, the head chip 20 in which the barrier layer 12 is laminated is arranged and bonded in each head chip arrangement hole 11b (third step). Here, the head chip 20 is bonded to the nozzle sheet 13 by thermocompression bonding while being aligned using a chip mounter. Further, in this case, thermocompression bonding is performed with an accuracy of, for example, about ± 1 μm so that the nozzle 13a is positioned directly below the heating resistor 22 of the head chip 20.

  Thus, when the head chip 20 on which the barrier layer 12 is formed is arranged in the head chip arrangement hole 11b and the nozzle sheet 13 and the head chip 20 are joined, the surface of the nozzle sheet 13 on the head chip 20 side, The ink liquid chamber 14 is formed by the barrier layer 12 and the surface of the head chip 20 on which the heating resistor 22 is formed as described above.

  Subsequently, the connection pads 23 provided on the head chip 20 side are electrically connected to the electrodes 13c (plating layer formed of gold on the outermost surface) of the wiring pattern portion 13b on the nozzle sheet 13 side. FIG. 8 is a plan view showing the arrangement of the connection pads 23 on the head chip 20 side. In FIG. 8, the nozzle 13a and the connection pad 23 are shown by solid lines. As shown in FIG. 8, one head chip 20 is provided with a plurality of connection pads 23 in advance along the longitudinal direction of the head chip 20. In addition, in FIG. 2 mentioned above, the positional relationship between the connection pad 23 and the wiring pattern portion 13b of the nozzle sheet 13 is illustrated in a sectional view.

FIG. 9 is a side cross-sectional view illustrating a method for connecting the connection pads 23 of the head chip 20 and the electrodes 13c of the wiring pattern portion 13b with the nozzle sheet 13.
As shown in FIGS. 2 and 9, an electrode 13c is provided at the tip of the wiring pattern portion 13b in the nozzle sheet 13 in the region of the head chip arrangement hole 11b of the module frame 11. Further, an opening 13 d is formed around the electrode 13 c of the nozzle sheet 13.

  Then, as shown in FIG. 9, a pin-like vibration tool T is inserted from the opening 13d on the surface opposite to the surface to which the module frame 11 of the nozzle sheet 13 is bonded. By applying sonic vibration, the connection pad 23 and the electrode 13c of the wiring pattern portion 13b are metal-bonded by ultrasonic waves. Then, after joining, the opening 13d is sealed with resin (see FIG. 2). As shown in FIG. 2, after sealing, the resin is made to substantially coincide with the surface of the nozzle sheet 13 (so as not to rise from the surface of the nozzle sheet 13).

  As shown in FIG. 2, a printed circuit board 31 is provided on the wiring pattern portion 13b of the nozzle sheet 13, and a conductor 31a is formed on the surface of the printed circuit board 31 that faces the wiring pattern portion 13b. ing. And this conductor 31a and the wiring of the wiring pattern part 13b are electrically connected. Thereby, the heating resistor 22 and the printed circuit board 31 (the heating resistor 22 and the connection pad 23, the connection pad 23 and the wiring pattern portion 13b, and the wiring pattern portion 13b and the printed circuit board 31) are electrically connected. Become.

  FIG. 10 is a side sectional view showing another embodiment of ultrasonic bonding. The example of FIG. 10 shows an example in which an opening for ultrasonic bonding is not formed in the nozzle sheet 13. In this case, as shown in FIG. 10, the vibration tool T is directly applied to the head chip 20 from the module frame 11 side via the head chip arrangement hole 11 b, and ultrasonic waves are applied to the head chip 20. To do. Even in this case, similarly to the above, the connection pads 23 of the head chip 20 and the electrodes 13c of the wiring pattern portion 13b can be ultrasonically bonded.

  Next, the buffer tank 15 is attached from the module frame 11 side. FIG. 11 is a plan view and a front view showing a state in which the buffer tank 15 is attached. FIG. 12 is a side sectional view showing a state in which the buffer tank 15 is attached.

  One buffer tank 15 is provided for one head module 10. As shown in FIG. 11, the buffer tank 15 has a shape slightly smaller than the module frame 11 when viewed in a plan view, but is substantially similar to the module frame 11. Further, as shown in FIG. 12, a common liquid flow path 15 a that is a cavity is formed inside the buffer tank 15. In particular, the buffer tank 15 of the present embodiment is formed such that the lower surface side (bonding surface side with the module frame 11) is opened, the side wall and the top wall are formed with the same thickness, and the cross section is substantially reverse concave. As a result, the common liquid channel 15a is formed.

  As shown in FIG. 12, the edge of the lower surface side of the buffer tank 15 and the module frame 11 are bonded together with an adhesive. When the buffer tank 15 is mounted on the module frame 11, as shown in FIG. 11, all the head chip arrangement holes 11b are covered. Further, as shown in FIG. 12, the common liquid flow path 15a of the buffer tank 15 and the ink liquid chamber 14 of each head chip 20 are connected via the flow path 16 between the head chip arrangement hole 11b and the head chip 20. Communicated. As a result, the buffer tank 15 forms a common liquid channel 15 a for all the head chips 20 in the head module 10.

  Further, as shown in FIG. 11, a hole 15b is formed in the top wall of the buffer tank 15, and ink is supplied from the ink tank (not shown) into the common liquid flow path 15a through the hole 15b. Is done.

  Here, as shown in FIG. 12, the inner edge (A portion in FIG. 12) on the lower surface side of the buffer tank 15 is formed in a convex section, and this convex section is in contact with the module frame 11. . Then, an adhesive is put on and bonded (joined) to the outside of this convex portion (the portion which is a step with respect to the convex portion, part B in FIG. 12). Thereby, both can be easily bonded, and the shape of the buffer tank 15 can be simplified. Further, on the lower surface side of the buffer tank 15, the adhesive portion enters the inside (on the side of the common liquid flow path 15 a or the head chip 20) due to the convex portion of the inner edge contacting the module frame 11. Can be prevented.

  In the case where the common liquid channel 15a is formed in the upper part of the head chip 20 and the upper part of the head chip 20 is sealed, for example, if there is too much adhesive, the adhesive enters the ink liquid chamber 14 and ink. There is a risk of clogging the liquid chamber. On the other hand, if the amount of the adhesive is too small, the upper part of the head chip 20 cannot be completely sealed, and ink leakage may occur. For this reason, it was necessary to sufficiently manage the amount of adhesive applied.

  However, in this embodiment, as described above, the buffer tank 15 enters the head chip placement hole 11b of the module frame 11 and is not bonded to the head chip 20 or the nozzle sheet 13, but only to the module frame 11. The By adopting such a shape, an advanced adhesive application technique is not required, and the adhesive application management is facilitated. Moreover, the frequency of occurrence of defects due to the application of the adhesive can be reduced.

  The head module 10 is completed as described above. In the head module 10 of the present embodiment, the nozzle sheet 13 in the head chip arrangement hole 11b does not come into contact (adhere) with parts other than the head chip 20, so that unnecessary stress is not applied to the nozzle sheet 13. Therefore, it is possible to ensure the flatness of the surface of the nozzle 13a and the high positional accuracy of the nozzle 13a.

  Furthermore, in the present embodiment, one liquid discharge head 1 is formed by using a plurality of the head modules 10. FIG. 13 is a plan view (upper side) and a front view (lower side) showing a state in which a plurality of head modules 10 are arranged side by side.

  The base jig C is made of a translucent material (for example, glass) and holds a holding plate C1 having a flat upper surface by a support frame C2. Further, an adhesive sheet C3 is bonded to the upper surface of the holding plate C1 (the surface on which the head module 10 is placed). The surface of this adhesive sheet C3 is also a flat surface. In the present embodiment, the pressure-sensitive adhesive sheet C3 is a UV sheet (a sheet provided with a pressure-sensitive adhesive layer having a function of losing adhesive force by irradiation with ultraviolet rays).

In the present embodiment, the four head modules 10 are aligned in series on the adhesive sheet C3 of the base jig C using a mounter (fourth step). Here, an alignment mark (not shown) is provided on the base jig C, and each head module 10 is disposed at a predetermined position with reference to the alignment mark. In this case, the engaging portions 11 a at both ends of each head module 10, that is, the portions cut out in a substantially L shape are engaged (coupled) with each other.
Further, the head module 10 placed on the base jig C is held at the placed position by the adhesive force of the adhesive sheet C3. That is, the nozzle sheet 13 of the head module 10 and the adhesive sheet C3 are adhered.

  By aligning the four head modules 10 in a row as described above, an A4-compatible line head is formed. Furthermore, four rows of the head modules (consisting of four head modules 10) are arranged in four rows (in the plan view of FIG. 13, three rows of head modules are arranged, and the bottom row of head modules 10 rows). 3 shows the state when three head modules 10 are already placed on the base jig C and the last one head module 10 is placed), Y, M, C, and K A color line head corresponding to four colors is formed.

  Further, when the plurality of head modules 10 are placed on the base jig C in this way, the ink droplet ejection surface (the surface on which the module frame 11 is bonded) of the nozzle sheet 13 in each head module 10. The opposite surface is located on the same plane (the surface on the adhesive sheet C3 of the base jig C).

  The two head modules 10 connected in series are respectively referred to as a head module “N” (left side) and a head module “N + 1” (right side), and the four head chips 20 in the head modules “N” and “N + 1”. Are 20A, 20B, 20C, and 20D in order from the left side, the head chip 20D of the head module “N” and the head chip 20A of the head module “N + 1” include at least one nozzle 13a. It arrange | positions so that it may overlap in a row direction. That is, among the head chips 20D of the head module “N”, the nozzle 13a that is closest to the head module “N + 1” is more than the nozzle that is closest to the head module “N” among the head chips 20A of the head module “N + 1”. Are also arranged on the right side.

As described above, after arranging four head modules 10 in one row, the head frame 2 and the head module 10 are bonded (fifth step). FIG. 14 is a plan view showing the head frame 2 immediately before being bonded to the head module 10.
The head frame 2 is made of a highly rigid metal plate or the like, and is formed with four head module arrangement holes 2a in which four head modules 10 arranged in series can be arranged. That is, with respect to the four head modules 10 arranged in series as shown in FIG. 13, when the head frame 2 is arranged from the upper side, the four head modules 10 are arranged inside. The hole 2a is formed.

  Further, as shown in FIG. 14, before the head frame 2 is bonded to the head module 10, the printed circuit board 3 is bonded to one surface side (the back surface side in FIG. 14) of the head frame 2 in a separate process. Has been. In FIG. 14, the outer shape of the printed circuit board 3 is illustrated by a dotted line. The printed circuit board 3 is formed so as to avoid the head module arrangement hole 2a of the head frame 2 when viewed in plan.

  Further, as shown in FIG. 14, a silicone (resin-based) adhesive D is applied in advance to the peripheral edge portion of the head chip arrangement hole 2 a on the lower surface side (printed circuit board 3 side) of the head frame 2. In FIG. 14, the area | region where the silicone adhesive D was apply | coated is shown by hatching.

  FIG. 15 is a front view showing a state when the head frame 2 is arranged from above with respect to the head module 10 arranged as shown in FIG. 13. When the head frame 2 is arranged in this way, as shown in FIG. 16, four head modules 10 arranged in series are arranged in each head module arrangement hole 2 a of the head frame 2. When the head frame 2 is arranged in this manner, the head frame 2 and the module frame 11 of the head module 10 come into contact with each other as shown in the side view in the X direction in FIG. Bonded with silicone adhesive. In the present embodiment, both are bonded by an adhesive, but a bonding method not using an adhesive may be used.

  In the above bonding, the buffer tank 15 of each head module 10 does not come into contact with the head module placement hole 2a as shown in the side view in the X direction in FIG. 1, the printed circuit board 3 is disposed between the module frames 11 of the head modules 10 without contacting the module frames 11 of the head modules 10.

  FIG. 17 is a front view showing the steps after the bonding. When the bonding between the head frame 2 and the head module 10 is completed, ultraviolet rays are irradiated from the back surface side of the holding plate C1 as shown in FIG. 17 (sixth step). In FIG. 17, the state of ultraviolet irradiation is shown by arrows. By this ultraviolet irradiation, the adhesive strength of the adhesive sheet C3 (adhesive) disappears. In addition, as the pressure-sensitive adhesive sheet C3 having such characteristics, a trade name “Selfa” manufactured by Sekisui Chemical Co., Ltd. may be mentioned. This pressure-sensitive adhesive sheet is a self-peeling pressure-sensitive adhesive tape, and its adhesive strength is reduced by irradiating with ultraviolet rays. At the same time, gas is generated at the adhesive interface between the pressure-sensitive adhesive tape and the adherend, and the pressure-sensitive adhesive sheet is filled. The tape has the property of peeling off itself.

  FIG. 18 is a front view showing a state in which the integrated head frame 2 and head module 10 are separated from the base jig C after the adhesive strength of the adhesive sheet C3 is lost as described above. After the adhesive strength of the adhesive sheet D is lost, the integrated head frame 2 and head module 10 can be easily separated from the base jig C (on the adhesive layer of the adhesive sheet C3).

  If the adhesive on both sides of the adhesive sheet C3 is of the same type, the adhesive force between the adhesive sheet C3 and the holding plate C1 also disappears due to the irradiation of the ultraviolet rays, so that the adhesive sheet C3 is removed from the holding plate C1. It can be easily separated. On the other hand, even if the adhesive between the adhesive sheet C3 and the holding plate C1 does not lose its adhesive strength by irradiation with ultraviolet rays, the adhesive sheet C3 can be peeled from the holding plate C1 after use. I just need it. When the process shown in FIG. 13 is performed again, the adhesive sheet C3 after use is peeled off from the holding plate C1, and a new adhesive sheet C3 may be attached to the holding plate C1.

The following process will be briefly explained. The wiring part of the printed circuit board 3 and the wiring pattern part 13b of the nozzle sheet 13 are overlapped by the adhesion between the head frame 2 and the head module 10 described above. Thus, the wiring process is performed. Next, the terminal portion soldered so as to surround the edge of the wiring pattern portion 13b is resin-coated (sealed) with a resin coating agent.
Through the above steps, the state shown in FIG. 1 is obtained, and the liquid discharge head 1 is formed.

Although one embodiment of the present invention has been described above, the present invention is not limited to the above-described embodiment, and various modifications such as the following are possible.
(1) In this embodiment, in order to fix the position of the head module 10 placed on the base jig C, the pressure-sensitive adhesive sheet C3 that loses the adhesive force by irradiation with ultraviolet rays is used. Various pressure-sensitive adhesives can be used. For example, you may use the adhesive which lose | disappears adhesive force by provision of heat (energy). Then, after the head frame 2 and the head module 10 are joined, heat (energy) is applied to the pressure-sensitive adhesive layer to eliminate the adhesive force of the pressure-sensitive adhesive layer, and the head frame 2 and the head module 10 are joined. Things may be separated from the adhesive layer.

  (2) Four head chip placement holes 11 b are formed in the module frame 11 so that four head chips 20 are mounted on one head module 10. However, the present invention is not limited to this, and any number of head chips 20 may be mounted on one head module 10.

  (3) In the case where the liquid discharge head 1 is formed as a line head, in this embodiment, four rows of head modules 10 in which four head modules 10 are connected in series are provided. The number of head modules 10 of one liquid discharge head 1 can be increased or decreased according to the use of the discharge head 1 and the number of colors.

FIG. 2 is a plan view showing an embodiment of a liquid discharge head according to the present invention and a side view (cross-sectional view) in the direction of the arrow in the X direction. FIG. 4 is a cross-sectional view showing a head chip mounted in a liquid discharge head and a configuration around the head chip and a plan view seen from the bottom surface. It is the top view and front view which show one head module. It is a top view which decomposes | disassembles and shows a nozzle sheet and a module frame. It is the top view and front view which show the state which has arrange | positioned the module frame on the nozzle sheet | seat. It is a top view which shows the state by which the nozzle row | line was formed in the nozzle sheet | seat in a head chip arrangement | positioning hole. It is a figure which shows the state which has arrange | positioned and fixed the head chip which laminated | stacked the barrier layer in each head chip arrangement | positioning hole. It is a top view which shows arrangement | positioning of the connection pad by the side of a head chip. It is side surface sectional drawing explaining the connection method of the connection pad of a head chip, and the electrode of the wiring pattern part with a nozzle sheet. It is sectional drawing of the side surface which shows other embodiment of ultrasonic bonding. It is the top view and side view which show the state which attached the buffer tank to the head module. It is sectional drawing of the side surface which shows the state in which the buffer tank was attached. It is the top view and front view which show the state which arranged the some head module side by side. It is a top view which shows the head frame just before adhere | attaching with a head module. It is a front view which shows a mode when a head frame is arrange | positioned from upper direction with respect to the head module arrange | positioned like FIG. It is a top view which shows the state by which the head module was arrange | positioned in each head module arrangement | positioning hole of a head frame. It is a front view which shows a mode that an ultraviolet-ray is irradiated from the back surface side of a holding plate. It is a front view which shows a mode that the head frame and head module which were united from the base jig | tool are isolate | separated.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Liquid discharge head 2 Head frame 2a Head module arrangement hole 3 Printed circuit board 10 Head module 11 Module frame 11a Engagement part 11b Head chip arrangement hole 12 Barrier layer 13 Nozzle sheet 13a Nozzle 13b Wiring pattern part 14 Ink liquid chamber 15 Buffer tank 15a Common liquid flow path 15b Hole 16 Flow path 20 Head chip 21 Semiconductor substrate 22 Heating resistor C Base jig C1 Holding plate C2 Support frame C3 Adhesive sheet D Silicone adhesive

Claims (5)

A head chip in which a plurality of energy generating elements are arranged in one direction at regular intervals;
A nozzle sheet formed with a nozzle array in which a plurality of nozzles for discharging droplets are arranged;
A liquid chamber forming member that is stacked between the formation surface of the energy generating element of the head chip and the nozzle sheet, and forms a liquid chamber between each of the energy generating elements and each of the nozzles;
A hole for supporting the nozzle sheet by being bonded to one surface of the nozzle sheet and arranging the head chip therein, and when the head chip is arranged in the region, the head A module frame having a head chip arrangement hole in which the nozzle row is located at a position facing each energy generating element of the chip;
A plurality of head modules for discharging the liquid in the liquid chamber from the nozzle by the energy generating element;
A liquid ejection device comprising: a head frame formed with a head module disposition hole for disposing a plurality of the head modules disposed in series inside, and a head frame joined to each of the head modules disposed in the head module disposition hole. A method of manufacturing a head,
A first step of joining the module frame to one surface of the nozzle sheet;
When the head chip is arranged in the area of the head chip arrangement hole, the nozzle is located at a position facing each energy generating element of the head chip in the nozzle sheet in the area of the head chip arrangement hole. A second step of forming the nozzle row to be disposed;
The liquid chamber is formed in the head chip arrangement hole so that each energy generating element of the head chip and each nozzle formed in the nozzle sheet in the area of the head chip arrangement hole face each other. A plurality of head modules are formed by a step including a third step of arranging and bonding the head chip provided with a member,
The plurality of head modules are positioned in a state where they are arranged in series on the pressure-sensitive adhesive layer of a holding plate provided with a flat surface having at least a surface made of the pressure-sensitive adhesive layer, and each head is controlled by the adhesive force of the pressure-sensitive adhesive layer A fourth step of maintaining the position of the module;
By mounting the head frame from above the plurality of head modules arranged in the fourth step, the plurality of head modules arranged in series are arranged in the head module arrangement hole of the head frame, and A fifth step of joining the head frame and each of the head modules;
After the joining in the fifth step, the sixth step of eliminating the adhesive force of the pressure-sensitive adhesive layer and separating the joined head frame and each head module from the pressure-sensitive adhesive layer. A method of manufacturing a liquid discharge head, which is characterized. In the manufacturing method of the liquid discharge head according to claim 1,
The method for manufacturing a liquid discharge head, wherein the pressure-sensitive adhesive layer used in the fourth step is provided with a film-like pressure-sensitive adhesive sheet on the surface of the holding plate. In the manufacturing method of the liquid discharge head according to claim 1,
An arrangement surface of at least the head module of the holding plate is formed from a translucent material,
The pressure-sensitive adhesive layer is one that loses adhesive strength by irradiation with ultraviolet rays,
The sixth step is a step of irradiating ultraviolet rays from the surface of the holding plate opposite to the surface on which the head module is disposed to eliminate the adhesive force of the adhesive layer. Production method. In the manufacturing method of the liquid discharge head according to claim 1,
The pressure-sensitive adhesive layer used in the fourth step is a film-like pressure-sensitive adhesive sheet provided on the surface of the holding plate, and loses the adhesive strength by irradiation with ultraviolet rays.
An arrangement surface of at least the head module of the holding plate is formed from a translucent material,
The sixth step is a step of irradiating ultraviolet rays from the surface of the holding plate opposite to the surface on which the head module is disposed to eliminate the adhesive force of the adhesive layer,
The method for manufacturing a liquid discharge head, wherein the pressure-sensitive adhesive sheet is formed so as to be peelable from the holding plate by irradiation with ultraviolet rays in the sixth step. In the manufacturing method of the liquid discharge head according to claim 1,
The pressure-sensitive adhesive layer loses the adhesive strength by applying energy,
The sixth step is a step of eliminating the adhesive force of the pressure-sensitive adhesive layer by applying energy to the pressure-sensitive adhesive layer.