JP2009061710A - Inkjet recording head and method for manufacturing it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a recording head capable of integrating a supporting member with a low linear expansion coefficient and a holding member, having a good quality of printing and printing at a high speed. <P>SOLUTION: In the recording head, a recording element substrate 34 is fixed on the holding member 31 through the supporting member 32. The supporting member 32 has the back face 32m on which the recording element substrate 34 is fixed, the front 32n positioned on the opposite side of the back face 32m and opposing to the holding member 31 and a plurality of side faces continuous to the front and the back faces. In addition, at least one side face 32t among a plurality of the side faces of the supporting member 32 is inclined so that it is separated from the other side faces opposing as it approaches the back face 32m. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an ink jet recording head (hereinafter sometimes referred to as “recording head”) mounted on an ink jet recording apparatus, and a method for manufacturing the same.

  As an effective means for improving the printing speed of the ink jet recording apparatus, the number of prints per scan (by extending the length of the recording element substrate in the longitudinal direction (discharge port array direction) and increasing the number of discharge ports ( A method for increasing the recording area) is mentioned.

  However, when the recording element substrate is lengthened in order to further increase the speed, the stress increases due to the difference in linear expansion coefficient between the material constituting the recording element substrate and the material constituting the holding member. It becomes a problem. Specifically, when the temperature rises during printing, stress is generated on the joint surface between the recording element substrate and the holding member due to the difference in linear expansion coefficient. As a result, the recording element substrate is deformed or damaged, and printing failure occurs.

  Therefore, a method is conceivable in which a support member having a low linear expansion coefficient is prepared on the support surface (fixed surface) of the recording element substrate of the holding member, and the support member is assembled and fixed to the holding member.

  As a method for fixing the support member and the holding member, a fixing method using an insert molding method can be considered in addition to fixing by an adhesive. Specifically, after the support member is inserted into the mold before the holding member is molded, the material resin of the holding member is poured into the mold, and the support member and the holding member are integrally molded, thereby supporting the support member. The member is fixed to the holding member.

Further, when the support member having a low linear expansion coefficient is a resin such as PPS to which carbon or glass is added, a two-color molding method can be used. For example, the support member can be fixed to the holding member by forming the support member by primary molding and then molding the holding member by secondary molding and integrally molding the support member.
JP 10-44420 A

  However, when trying to obtain a joined body of a support member and a holding member by an insert molding method or a two-color molding method, the following problems occur. That is, as shown in FIG. 5, when an assembly of the support member 200 and the holding member 150 is obtained by an insert molding method or the like, the material resin P of the holding member 150 is exposed on the support member 200. As a result, the surface 201 of the support member 200 to which the recording element substrate is fixed later may be covered with the material resin P. Such a phenomenon occurs when the material resin P enters between the surface 201 and the mold surface (cavity forming surface) during molding.

  When the support member 200 is covered with the material resin P, not only the linear expansion of the surface 201 of the support member 200 is hindered, but also the surface 201 is uneven and the flatness is also lowered. Further, the support member 200 inserted into the mold (into the cavity) is fixed in the mold by suction or mechanical clamp when integral molding is performed. When insert molding is performed by these fixing methods, In addition, the following problems may occur.

[When fixing by adsorption]
When the support member 200 is fixed in the mold by suction, the support member 200 is fixed to the mold by the surface 201 being sucked through the suction holes provided in the mold. When the intrusion of the resin as described above (the intrusion of the material resin P between the surface 201 on which the recording element substrate is supported and fixed) and the mold surface occurs, the resin reaches the adsorption hole of the mold. May cause clogging.

[When fixing with mechanical clamp]
When the support member 200 is fixed in the mold by the mechanical clamp, the side surface of the support member 200 is fixed by the fixing mechanism by the mechanical clamp provided in the mold and is fixed to the mold. At this time, the support member 200 may be deformed or cracked by an external force applied to the side surface by the mechanical clamp.

  From the above, it is necessary to fix the support member in the mold and perform integral molding with the holding member, regardless of the suction method or the mechanical clamp method.

  An object of the present invention is to make it possible to integrate a support member and a holding member having a low linear expansion coefficient while avoiding the above-mentioned problems, and to have a good print quality and capable of high-speed printing. Is to realize the head.

  The ink jet recording head of the present invention is an ink jet recording head in which at least one recording element substrate having ink ejection means is fixed to a holding member via a support member. The support member has a back surface to which the recording element substrate is fixed, a surface that is located on the opposite side of the back surface and that faces the holding member, and a plurality of side surfaces that are continuous with the front and back surfaces. Furthermore, at least one of the plurality of side surfaces of the support member is inclined so as to be separated from the other side surfaces facing each other as it approaches the back surface.

An ink jet recording head manufacturing method according to the present invention is a method for manufacturing an ink jet recording head in which at least one recording element substrate provided with an ink discharge means is fixed to a holding member via a support member. (1) It has the process of (2).
(1) It has a back surface to which the recording element substrate is fixed, a surface opposite to the back surface, and a plurality of side surfaces continuous to the front and back surfaces, so that at least one of the side surfaces is separated from the facing side surface as it approaches the back surface. The step of disposing the inclined support member in the mold so that the back surface faces the mold surface (2) Supplying the material resin of the holding member into the mold in which the support member is disposed, along the back surface The process of integrally molding the support member and the holding member while pressing the support member against the mold surface by the pressure of the flowing material resin

  According to the present invention, at least one of the above-mentioned problems can be solved and the intended purpose can be achieved.

  Hereinafter, an example of an embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is an exploded perspective view showing the configuration of the recording head 3 according to the present embodiment. FIG. 2 is an explanatory view showing the support member 32 provided in the recording head 3 shown in FIG. FIG. 3A is a schematic cross-sectional view showing a part of the manufacturing process of the recording head 3 shown in FIG.

  In the recording head 3 shown in FIG. 1, a recording element substrate H34 is bonded and fixed with a first adhesive to an ink supply assembly 33 in which a holding member 31 and a support member 32 having a low linear expansion coefficient are integrated. Yes.

  The basic structure of the recording element substrate 34 is the same as a known recording element substrate. That is, a plurality of ejection openings capable of ejecting the recording liquid are arranged along the long side of the ink supply opening. However, the recording element substrate 34 is longer in the direction of the discharge port array than the conventional general substrate, and has more discharge ports. Specifically, the recording element substrate 34 has a width of 2 to 3 mm, a length (discharge port direction) of 25 to 35 mm, and a thickness of 0.5 to 0.8 mm.

  As described above, the support member 32 having a low linear expansion coefficient is integrated with the holding member 31. Specifically, the support member 32 is integrated with the holding member 31 so that a first surface 32m (hereinafter referred to as “back surface 32m”) to which the recording element substrate 34 is bonded and fixed is exposed, and ink supply is performed. The joined body 33 is configured.

  The recording element substrate 34 is bonded and fixed to the ink supply assembly 33 with high accuracy by a first adhesive. At this time, the ink supply port (not shown) of the recording element substrate 34, the ink supply port 32s of the support member 32, and the ink supply port 31s of the holding member 31 are all arranged and fixed so as to communicate with each other. With the above configuration, the recording liquid stored in the holding member 31 is supplied to the recording element substrate 34 and discharged from the discharge port.

  The support member 32 will be described in more detail with reference to FIGS. 1 and 2. The support member 32 is a member having a substantially rectangular planar shape and a thickness (t) of 1 to 3 mm, and the recording element substrate 34 is bonded and fixed to the back surface 32m. That is, the back surface 32 m is a support surface that supports the recording element substrate 34. Here, for convenience of explanation, the second surface opposite to the back surface 32m, which is the support surface of the recording element substrate 34, is defined as the front surface 32n. A third surface connecting the back surface 32m and the front surface 32n is defined as a side surface 32t.

  Based on the above definition, the shape of the support member 32 will be described in more detail. As shown in FIGS. 1 and 2, the pair of opposing side surfaces 32t of the support member 32 are inclined so as to be separated from each other as the back surface 32m is approached. In other words, the cross section parallel to the longitudinal direction (substrate discharge port array direction) of the support member 32 has a substantially trapezoidal shape that gradually expands from the front surface 32n side to the back surface 32m side. However, only one of the pair of side surfaces 32t may be inclined so as to gradually move away from the other as it approaches the back surface 32m.

  As shown in FIG. 2, the side surface 32t of the support member 32 is inclined such that the inclination angle (θ) with respect to the back surface 32m is 70 ° to 85 °. The width (w) of the support member 32 is 2.5 to 4.0 mm, and the length (L) in the discharge port array direction is 26.0 to 37.0 mm. Further, the above-described ink supply port 32 s is formed at the center of the support member 32. The width (wl) of the ink supply port 32s is 1.0 to 1.5 mm, and the supply port length (Ls) is 23.0 to 33.0 mm.

As the material of the support member 32, a material having a low coefficient of linear expansion (desirably 25 ppm or less) and a material that does not easily corrode even when in contact with the recording liquid is selected. Specific examples of such materials include Al ₂ O ₃ (alumina), ZrO ₂ (zirconia), Si ₃ N ₄ (silicon nitride), SiC (silicon carbide), or AlN (nitriding). (Aluminum-based) ceramics. Moreover, metals such as SUS316, Cu, Ag, and Au, and PPS, PET, and PP resins are also included. In addition, SiO ₂ (quartz) is an example of the material of the support member 32. When the support member 32 is formed of resin, carbon, ceramic, glass, or the like may be mixed to improve the shape rigidity. The support member 32 can be manufactured by injection molding, compression molding, or cutting.

  Next, a method for manufacturing the recording head 3 shown in FIG. 1 will be described. Of course, the description of the manufacturing process of the recording head 3 that is the same as the conventional process is omitted, and only the characteristic process of the manufacturing method of the recording head of the present invention is described. That is, a process of obtaining the ink supply joined body 33 by integrating (integral molding) the holding member 31 and the support member 32 will be described below.

  As described above, the ink supply joined body 33 can be manufactured by an insert molding method or a two-color molding method. Fig.3 (a) is the schematic diagram which showed the state at the time of integrating the support member 32 and the holding member 31 by the insert molding method.

  The support member 32 formed in advance has a back surface 32m serving as a support surface of the recording element substrate 34 in a direction facing the mold surface (cavity forming surface) C1 of the first mold C. Inserted into the cavity. At this time, the mold protrusion C2 of the first mold C is inserted into the ink supply port 32s (FIG. 1) of the support member 32, and the position is determined. Further, at the time of molding, the back surface 32m of the support member 32 to which the recording element substrate 34 is fixed is brought into contact with the mold surface C1. Since the back surface 32m of the support member 32 is required to have high flatness, it is desirable that the mold surface C1 is suppressed to a flatness of 5 μm or less. The clearance between the support member 32 and the second mold D is 0.02 to 0.07 mm when the mold is closed. When there is no clearance, when the mold is closed, a load due to the clamping force is applied to the support member 32, and the support member 32 is deformed or damaged.

  After the support member 32 is inserted into the first mold C, the mold is closed, and the material resin of the holding member 31 is supplied from the gate 15g. The material resin supplied from the gate 15g spreads in the mold in accordance with the flow direction FD and reaches the inserted support member 32. The material resin that has reached the support member 32 flows along the inclined side surface 32 t of the support member 32. When the material resin flows along the inclined side surface 32t, a pressing force N in the mold direction is applied to the side surface 32t by the resin pressure, and the back surface 32m of the support member 32 is pressed against the mold surface C1. . As a result, intrusion of the material resin into the gap between the mold surface C1 and the back surface 32m of the support member 32 is prevented.

  Here, when the side surface 32m of the support member 32 is not inclined, the pressing force N in the mold direction is not generated, and the support member 32 is displaced by the resin pressure. Then, the material resin enters the gap between the mold surface C1 and the back surface 32m of the support member 32. As a result, the material resin is exposed on the back surface 32m of the support substrate 32 to which the recording element substrate 34 is fixed (see FIG. 5).

  In order to generate the above-described operational effects, that is, the pressing force N in the mold direction that only prevents the intrusion of the material resin, the inclination angle (θ) of the side surface 32m of the support member 32 needs to be 85 ° or less. There is. On the other hand, if the inclination angle (θ) is excessively small, the pressing force N in the mold direction generated by the resin pressure becomes excessive, and the rigidity of the support member 32 decreases due to the thinning. As an influence thereof, a bending wa occurs on the back surface 32m to which the recording element substrate 34 is fixed (see FIG. 3B). Considering the above, the inclination angle (θ) of the side surface 32t of the support member 32 is desirably 70 to 85 °.

  Next, among the plurality of side surfaces of the support member 32, it is desirable to incline the set of side surfaces 32t intersecting the discharge port array direction as described above. The reason will be described below.

  As described above, the support substrate 32 is formed with the ink supply port 32s (FIG. 1). The ink supply port 32s is an elongated hole along the discharge port array direction. Accordingly, the support member 32 is less rigid with respect to a force from a direction (short direction) perpendicular to the discharge port array than in a direction (longitudinal direction) parallel to the discharge port array. As a result, when the above-mentioned inclination is provided on the side surface parallel to the discharge port array direction, as shown in FIG. 3C, when the resin pressure is applied at the time of molding, a deflection wa occurs, and the flatness of the back surface 32m is lowered. May end up. Therefore, among the four side surfaces of the support member 32, it is desirable to incline the side surface 32t perpendicular to the discharge port array direction as described above.

  As described above, by inclining the side surface 32t of the support member 32, the intrusion of the resin between the back surface 32m and the mold surface C1 is prevented, and the ink supply joined body 33 having no resin exposure is formed on the back surface 32m. Can be obtained (see FIG. 4). As a result, in the ink supply assembly 33, the surface on which the recording element substrate 34 is supported and fixed (the back surface 32m of the supporting member) is reduced in linear expansion, and the elongated recording element substrate 34 can also be mounted. .

  Since it becomes possible to mount the elongated recording element substrate 34, it is possible to realize an ink jet recording head having good printing quality and capable of high-speed printing.

  At the same time, since the support member 32 can be brought into contact with the mold surface C1 by the resin pressure at the time of molding, the suction mechanism and the clamp mechanism for fixing the support member 32 in the mold can be fixed. A mechanism is also unnecessary.

  The present invention is effective not only for black recording heads but also for color recording heads, and is applicable to both recording heads. Further, not only when the support member and the holding member are integrally molded by the insert molding method, but also when the members are integrally molded by the two-color molding method, the same effect as described above can be obtained. . When the support member and the holding member are integrally formed by the two-color molding method, the holding member is formed by using all or part of the mold used for forming the support member as it is.

FIG. 3 is an exploded perspective view illustrating an example of an embodiment of a recording head of the present invention. It is an enlarged view of the branch member shown in FIG. (A) is typical sectional drawing which shows a part of manufacturing process of the recording head shown in FIG. (B) (c) is explanatory drawing which shows a mode that bending arises in a supporting member. It is explanatory drawing which shows one of the effects by this invention. It is a perspective view which shows the state which resin exposed to the support surface of the support member.

Explanation of symbols

31 holding member 32 support member 32m back surface 32n surface 32t side surface 34 recording element substrate C first mold C1 mold surface D second mold

Claims (11)

In an ink jet recording head in which at least one recording element substrate provided with ink ejection means is fixed to a holding member via a support member,
The support member has a back surface to which the recording element substrate is fixed, a surface that is located on the opposite side of the back surface and that faces the holding member, and a plurality of side surfaces that are continuous with the back surface and the surface,
At least one of the plurality of side surfaces is inclined so as to be separated from other opposing side surfaces as the back surface is approached.   An inkjet recording head characterized in that at least one pair of side surfaces facing each other among the plurality of side surfaces are inclined so as to be separated from each other as they approach the back surface.   3. The ink jet recording head according to claim 1, wherein the inclined side surface is a side surface intersecting with a longitudinal direction of the recording element substrate.   The inkjet recording head according to claim 1, wherein the support member has a linear expansion coefficient of 25 ppm or less. Said support member, Al ₂ O ₃ system, ZrO ₂ system, Si ₃ N ₄ system, the ink jet recording head according to claim 4, characterized in that it is formed of a ceramic of SiC-based or AlN-based.   5. The ink jet recording head according to claim 4, wherein the support member is made of a PPS, PET, or PP resin.   5. The ink jet recording head according to claim 4, wherein the supporting member is made of any one of SUS, Cu, Ag, and Au. The ink jet recording head according to claim 4, wherein the supporting member is made of SiO ₂ .   The ink jet recording head according to claim 6, wherein carbon, ceramic, or glass is mixed in the resin. In a method for manufacturing an ink jet recording head, wherein at least one recording element substrate having ink ejection means is fixed to a holding member via a support member.
A back surface to which the recording element substrate is fixed; a surface positioned on the opposite side of the back surface; and the back surface and a plurality of side surfaces connected to the surface. At least one of the plurality of side surfaces is on the back surface The step of disposing the support member that is inclined so as to be separated from the other side surface facing as it approaches, in the mold such that the back surface faces the mold surface;
Supplying the material resin of the holding member into the mold in which the support member is disposed, and pressing the support member against the mold surface by the pressure of the material resin flowing along the back surface, And a step of integrally forming the holding member. A method of manufacturing an ink jet recording head, comprising: In a method for manufacturing an ink jet recording head, wherein at least one recording element substrate having ink ejection means is fixed to a holding member via a support member.
A back surface to which the recording element substrate is fixed; a surface positioned on the opposite side of the back surface; and the back surface and a plurality of side surfaces connected to the surface. At least one of the plurality of side surfaces is on the back surface Forming the support member that is inclined so as to be separated from other side surfaces facing as it approaches, in a mold such that the back surface faces the mold surface;
While supplying the material resin of the holding member into the mold in which the support member is molded, and pressing the support member against the mold surface by the pressure of the material resin flowing along the back surface, the support member and And a step of integrally forming the holding member. A method of manufacturing an ink jet recording head, comprising: