JP2013059886A - Liquid droplet ejection head, liquid droplet ejection device, inkjet head and image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce variations in liquid droplet ejection characteristics.SOLUTION: Even in such a case that a sealant 231 for protecting a drive IC 221 from the outside environment such as an outside air temperature, moisture, and mechanical stress is applied before a heat dissipation member 232 is adhered on the outer surface of the drive IC 221, lyophobic treatment is applied to the adhesion part of the outer surface of the drive IC 221 to be adhered to the adhesion surface of the heat dissipation member 232 before the heat dissipation member 232 is adhered to the outer surface of the drive IC 221. Accordingly, the sealant 231 is prevented from entering the adhesion part.

Description

  The present invention relates to a droplet discharge head, a droplet discharge device, an inkjet head, and an image forming apparatus.

  Conventionally, an electromechanical conversion element configured such that an electromechanical conversion film is sandwiched between electrodes includes, for example, a liquid discharge head that discharges ink droplets, and forms an image by adhering ink droplets to a sheet while conveying a medium. Used in an ink jet recording apparatus. The medium here is also referred to as “paper”, but the material is not limited, and a recording medium, a recording medium, a transfer material, a recording paper, and the like are also used synonymously. The image forming apparatus means an apparatus for forming an image by discharging a liquid onto a medium such as paper, thread, fiber, fabric, leather, metal, plastic, glass, wood, ceramics. The image formation is not only giving an image having a meaning such as a character or a figure to the medium but also giving an image having no meaning such as a pattern to the medium (simply ejecting a droplet). Also means. The ink is not limited to so-called ink, and is not particularly limited as long as it becomes liquid when ejected. For example, the ink is a generic term for liquids including DNA samples, resists, pattern materials, and the like. Use.

  The ink jet recording apparatus mainly includes a nozzle that discharges ink droplets, a discharge chamber that communicates with the nozzle, a liquid chamber called a pressurized liquid chamber, a pressure chamber, and an ink flow path chamber, and ink in the liquid chamber. And pressure generating means for discharging. As this pressure generating means, a piezo-type pressure generating means that is deformed and displaced in accordance with an applied voltage is known. The electromechanical conversion element (pressure generation element) used for the piezoelectric pressure generating means is a laminate of a common electrode, an electromechanical conversion layer, and an individual electrode. In this electromechanical conversion element, the common electrode is grounded (earthed), and a droplet discharge signal from the driving IC is supplied to the individual electrode via wiring deposited on the substrate. The electromechanical conversion element deforms and displaces the diaphragm forming the wall surface of the discharge chamber, thereby increasing the internal pressure of the pressurized liquid chamber and discharging ink droplets from the nozzles.

  In recent years, there has been an increasing demand for miniaturization in ink jet recording apparatuses. As one method for meeting this requirement, there is a method in which a drive IC (drive element) is provided in the vicinity of the electromechanical conversion element and the wiring length of the wiring board is shortened. When the drive IC (drive element) is provided in the vicinity of the electromechanical conversion element in this way, heat generated by the heat generated by the drive IC is easily transmitted to the electromechanical conversion element. Also transmitted to ink. For this reason, there is a possibility that the viscosity of the ink in the individual liquid chamber changes and the droplet discharge characteristics vary. In order to suppress variations in droplet discharge characteristics while reducing the size, it is necessary to release heat due to heat generated by the driving IC.

  As a heat dissipation method for this drive IC, the one described in Patent Document 1 is known. In this heat dissipation method of Patent Document 1, heat generated by the heat generation of the drive IC is released to the surface of the drive IC opposite to the surface of the drive IC provided with a connection terminal for electrical connection with the wiring of the wiring board. The metal plate (heat radiating member) to be bonded is adhered. The heat generated by the heat generated by the drive IC is transferred to the metal plate bonded to the drive IC, and is released from the exposed surface of the metal plate. In addition, a low-viscosity liquid sealant in which a sealing material for protecting the drive IC from outside temperature, moisture and mechanical stress is dissolved in a solvent is applied so as to cover the drive IC leaving the surface of the metal plate exposed. Is done.

  In the heat dissipation method of Patent Document 1, a driving IC is mounted on a wiring board, electrical connection is made between the wiring of the wiring board and a connection terminal of the driving IC, and then a metal plate is bonded onto the driving IC. Finally, a sealant is applied. On the other hand, when pursuing the downsizing of the droplet discharge head, which is a recent request as described above, the size of the driving IC is reduced. In order to suppress variations in droplet discharge characteristics, it is desirable to reduce the desired heat dissipation effect on the metal plate of the heat dissipation member as much as possible. Therefore, the size of the metal plate of the heat dissipation member cannot be reduced. As a result, the size of the metal plate of the heat dissipation member is larger than the size of the drive IC. And in the mounting process in that case, it mounts in order with a small size of a structural member from the ease of work. First, the driving IC is mounted on the wiring board, the wiring of the wiring board is electrically connected to the connection terminal of the driving IC, then the sealing agent is applied, and finally the metal plate is attached at the bonding position of the driving IC. Glue. In the case of this mounting process, since the contact between the drive IC and the metal plate becomes sufficient, the sealant is not applied to the bonding portion between the drive IC and the metal plate. On the other hand, in order to sufficiently perform the above function of the sealant, it is necessary to cover the entire driving IC with the sealant as much as possible. Therefore, it is desirable to apply the sealant to a location close to the end of the metal plate when the metal plate is bonded to the bonding location. However, even if the sealant is applied to a position close to the end of the metal plate, the sealant may penetrate into the bonding portion due to the wettability (lyophilicity) of the outer surface of the drive IC. If the metal plate is bonded to the bonding position of the driving IC with the sealing agent intruding into the bonding position, the sealing agent is interposed between the outer surface of the driving IC and the bonding surface of the metal plate. . For this reason, there is a problem in that the contact area between the driving IC and the metal plate is reduced by the area where the sealant enters, and the heat dissipation effect by the metal plate is reduced. Therefore, it is impossible to prevent the heat generated by the driving IC from being transmitted to the ink in the individual liquid chamber, and to solve the above problem that the viscosity of the ink in the individual liquid chamber changes and the droplet discharge characteristics vary. I couldn't.

  The present invention has been made in view of the above problems, and its purpose is to prevent the sealing agent from entering the contact portion between the driving IC and the heat radiating member and to prevent the heat radiating effect of the heat radiating member from being lowered. Accordingly, it is an object to provide a droplet discharge head, a droplet discharge device, an inkjet head, and an image forming apparatus that can reduce variations in droplet discharge characteristics.

  In order to achieve the above object, the invention of claim 1 includes at least a nozzle plate provided with nozzles for discharging droplets, and a pressurized liquid chamber which is joined to the nozzle plate and contains liquid therein. A liquid chamber plate to be formed; a pressure generating element for increasing the internal pressure in the pressurized liquid chamber to discharge liquid from the nozzle; and a drive element for supplying a droplet discharge signal to the pressure generating element; In the droplet discharge head that adheres a heat radiating member to the outer surface of the drive element that forms the structure, and releases heat generated by the heat generated by the drive element to the outside through the heat radiating member, the drive element that faces the adhesive surface of the heat radiating member The lyophobic treatment is performed on the bonding portion that is bonded to the bonding surface of the heat radiating member on the outer surface. The lyophobic treatment here is a manifestation reforming treatment that makes it difficult to mix with or dissolve in a liquid containing water and increases the contact angle of the liquid.

  In the present invention, as described above, even if the sealing agent for protecting the driving element is applied to the portion close to the adhesive portion before the heat radiating member is bonded to the outer surface of the driving element, the heat radiating member is attached to the driving element. If the lyophobic treatment is applied to the bonding portion of the driving element to be bonded to the bonding surface of the heat dissipation member before bonding to the outer surface, the sealing agent does not enter the bonding portion. As a result, the bonding surface of the heat dissipation member and the outer surface of the drive element facing the bonding surface are directly contacted and bonded at the bonding portion, thereby suppressing a decrease in the heat dissipation effect of the heat dissipation member. it can. Therefore, a droplet discharge head that can reduce the influence of heat on the liquid in the pressurized liquid chamber due to the heat generated by the drive element provided in the vicinity of the pressurized liquid chamber, and can reduce variations in droplet discharge characteristics. Can provide.

  According to the present invention, it is possible to reduce the variation in droplet discharge characteristics.

It is a schematic block diagram which shows the example of 1 structure of the droplet discharge apparatus of this invention. It is a schematic perspective view of a droplet discharge device. It is sectional drawing of the inkjet head which concerns on embodiment of this invention. It is process sectional drawing which shows the installation process of the heat radiating member in the droplet discharge head of this embodiment. It is process sectional drawing which shows the installation process of the heat radiating member in the droplet discharge head as a 1st modification of this embodiment. It is process sectional drawing which shows the installation process of the heat radiating member in the droplet discharge head as a 2nd modification of this embodiment. It is process sectional drawing which shows the installation process of the heat radiating member in the droplet discharge head as a 3rd modification of this embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a schematic configuration diagram showing a configuration example of a droplet discharge device of the present invention. FIG. 2 is a schematic perspective view of the droplet discharge device. An ink jet recording apparatus 100 as an example of the droplet discharge apparatus of the present invention shown in both figures mainly includes a carriage 101 that can move in the main scanning direction inside the recording apparatus main body, and the present invention mounted on the carriage 101. The printing mechanism unit 104 is configured to include a recording head 102 including an inkjet head, which is an example of a liquid droplet ejection head manufactured as described above, and an ink cartridge 103 that supplies ink to the recording head 102. In addition, a sheet feeding cassette 106 capable of stacking a large number of sheets 105 can be detachably attached to the lower part of the apparatus main body from the front side, and a manual feed tray 107 for manually feeding sheets 105 is provided. The paper 105 fed from the paper feed cassette 106 or the manual feed tray 107 can be taken in, and a required image is recorded by the printing mechanism 104, and then discharged to a paper discharge tray 108 mounted on the rear side. Make paper.

  The printing mechanism unit 104 holds a carriage 101 slidably in the main scanning direction by a main guide rod 109 and a sub guide rod 110 which are guide members horizontally mounted on left and right side plates (not shown). (Y), cyan (C), magenta (M), and black (Bk) ink droplets are ejected from a recording head 102, which is an example of a droplet ejection head according to the present invention that ejects ink droplets of each color. Outlets (nozzles) are arranged in a direction crossing the main scanning direction, and are mounted with the ink droplet ejection direction facing downward. In addition, each ink cartridge 103 for supplying ink of each color to the recording head 102 is replaceably mounted on the carriage 101. The ink cartridge 103 has an air port that communicates with the atmosphere upward, a supply port that supplies ink to the recording head 102 below, and a porous body filled with ink inside. The ink supplied to the recording head 102 by the force is maintained at a slight negative pressure.

  Further, although the heads of the respective colors are used here as the recording heads 102, a single head having nozzles for ejecting ink droplets of the respective colors may be used. Here, the carriage 101 is slidably fitted to the main guide rod 109 on the rear side (downstream side in the paper conveyance direction), and is slidably mounted on the sub guide rod 110 on the front side (upstream side in the paper conveyance direction). doing. In order to move and scan the carriage 101 in the main scanning direction, a timing belt 114 is stretched between a driving pulley 112 and a driven pulley 113 that are rotationally driven by a main scanning motor 111, and the timing belt 104 is moved to the carriage 101. The carriage 101 is reciprocally driven by forward and reverse rotations of the main scanning motor 111.

  On the other hand, in order to convey the paper 105 set in the paper feed cassette 106 to the lower side of the recording head 102, the paper feed roller 115 and the friction pad 116 for separating and feeding the paper 105 from the paper feed cassette 106 and the paper 105 are guided. A guide member 117 that rotates, a conveyance roller 118 that reverses and conveys the fed paper 105, a conveyance roller 119 that is pressed against the peripheral surface of the conveyance roller 118, and a feeding angle of the sheet 105 from the conveyance roller 118. A tip roller 120 is provided. The transport roller 118 is rotationally driven by a sub-scanning motor 121 through a gear train. A printing receiving member 122 is provided as a paper guide member that guides the paper 105 fed from the transport roller 118 on the lower side of the recording head 102 corresponding to the movement range of the carriage 101 in the main scanning direction. A conveyance roller 123 and a spur 124 that are rotationally driven to send the paper 105 in the paper discharge direction are provided on the downstream side of the printing receiving member 122 in the paper conveyance direction, and the paper 105 is further delivered to the paper discharge tray 108. A roller 125 and a spur 126, and guide members 127 and 128 that form a paper discharge path are disposed.

  At the time of recording, the recording head 102 is driven in accordance with the image signal while moving the carriage 101, thereby ejecting ink onto the stopped paper 105 to record one line. Record the line. Upon receiving a recording end signal or a signal that the trailing edge of the paper 105 has reached the recording area, the recording operation is terminated and the paper 105 is discharged.

  Further, a recovery device 129 for recovering the ejection failure of the recording head 102 is disposed at a position outside the recording area on the right end side in the movement direction of the carriage 101. The recovery device 129 includes a cap unit, a suction unit, and a cleaning unit. The carriage 101 is moved to the recovery device 129 side during printing standby, and the recording head 102 is capped by the capping means, and the ejection port portion is kept in a wet state to prevent ejection failure due to ink drying. Further, by ejecting ink that is not related to recording during recording or the like, the ink viscosity of all the ejection ports is made constant and stable ejection performance is maintained.

  FIG. 3 is a cross-sectional view of the inkjet head according to the embodiment of the present invention. The ink jet head 200 shown in the figure shows a detailed configuration of four color head parts, a yellow head part 201Y, a magenta head part 201M, a cyan head part 201C, and a black head part 201K. The inkjet head 200 includes a nozzle substrate 203 on which nozzles 202 for ejecting ink are formed, a restrictor 204 that prevents backflow of ink, and an individual channel plate 206 on which individual channels 205 are provided for each nozzle. It is comprised including. Then, the vibration plate 207 for pushing the ink in the individual flow path 205 to eject it from the nozzle 202, the vibration plate 207 to be deformed to push the ink, and the pressure generation comprising the individual electrode 208 and the PZT which is the electromechanical conversion element A pressure generating unit including the element 209 and the common electrode 210, an insulating layer 211 for preventing a short circuit between the individual electrode 208 and the common electrode 210, a support member 212 for the pressure generating unit, and four common flow path forming members 213, 214, 215, and 216 It is comprised including. Then, the common flow paths 217, 218, 219, and 220 formed by the common flow path forming members 213, 214, 215, and 216, the drive IC 221 that drives the inkjet head, and the drive signal from the drive IC 221 are the individual electrodes of the pressure generating unit. Solder balls 222 and 223 to be supplied to 208, a heat radiating member 224 that dissipates heat due to heat generated by the drive IC 221, and a sealant 225 that seals the drive IC 221. The common flow paths 217, 218, 219, and 220 are filled with inks of four colors, yellow, magenta, cyan, and black, respectively.

  The drive IC 221 outputs a drive signal for driving the inkjet head. Four color ink ejection control is performed by two drive ICs 221. The drive IC 221 generates heat when a drive signal is output to the pressure generator. Therefore, there is a possibility that the drive IC 221 itself is destroyed due to heat generated by the drive IC 221. In addition, when the heat generated from the drive IC 221 is transmitted to the ink in the individual liquid chamber in which the electromechanical conversion element is provided, the viscosity of the ink changes and the discharge characteristics vary. For this reason, it is necessary to release the heat generated from the driving IC. In order to prevent the destruction of the drive IC 221 and the fluctuation of the discharge characteristics, it is necessary to dissipate heat due to the heat generated by the drive IC 221.

FIG. 4 is a process cross-sectional view illustrating a process of installing a heat radiating member in the droplet discharge head of the present embodiment. In the figure, the same reference numerals as those in FIG. 3 denote the same components.
As shown to (a) of the figure, the hydrophobic film 230 is formed in the surface (installation surface of a heat radiating member) on the opposite side to the joint surface connected with the wiring board of drive IC221. The width of the area subjected to the lyophobic process (the width in the direction perpendicular to the nozzle row) is the entire width of the installation surface of the drive IC 221. The hydrophobic film 230 is formed of a thiol group solvent such as dodecanethiol or a silane coupling agent such as tetrahydrodecyltriethoxysilane. Here, it is known that when a liquid is applied to the boundary between the hydrophobic film and the hydrophilic film at a portion where the hydrophobic film and the hydrophilic film are continuous, the liquid moves from the hydrophobic film side to the hydrophilic film side due to surface tension. . Based on this principle, as shown in FIG. 5B, a sealant 231 is applied to the peripheral portion and the lower portion of the drive IC 221. At this time, since the lyophobic treatment is performed on the installation surface of the drive IC 221, the sealant 231 is not applied to the installation surface of the drive IC 221. This hydrophobic treatment is a manifestation reforming treatment that makes it difficult to mix or dissolve in water and increases the contact angle of water, but it also has the same effect on liquids other than water. Including treatment (lyophobic treatment). Next, as shown in FIG. 3C, a heat radiating member 232 for radiating heat generated by the heat generated by the drive IC 221 is provided in close contact with the installation surface of the drive IC 221. The width of the flat surface portion of the heat radiating member 232, that is, the surface that is in close contact with the installation surface of the drive IC 221 (indicated by W1 in FIG. 4) is greater than the entire width of the installation surface of the drive IC 221 (indicated by W2 in FIG. 4). It is narrower. As a result, the heat generated by the driving IC 221 can be effectively radiated from the heat radiating member 232. Then, as shown in FIG. 4D, a sealant 231 is applied so as to cover a part other than the part (exposed part to the space) of the heat radiating member 232 so that part of the heat radiating member 232 is exposed. To do. The heat dissipating member 232 is preferably made of a material having high thermal conductivity such as copper or aluminum. Further, since the width W1 of the flat surface portion of the heat radiation member 232 is narrower than the entire width W2 of the installation surface of the drive IC 221 (W1 <W2), the flat surface portion of the heat radiation member 232 is in close contact with at least the installation surface of the drive IC 121.

FIG. 5 is a process cross-sectional view illustrating a process of installing a heat radiating member in the droplet discharge head of the first modification of the present embodiment. In the figure, the same reference numerals as those in FIG. 4 denote the same components.
As shown to (a) of the figure, the hydrophobic film 230 is formed in the surface (installation surface of a heat radiating member) on the opposite side to the joint surface connected with the wiring board of drive IC221. The width of the lyophobized area is smaller than the entire width of the installation surface of the drive IC 221. Then, as shown in FIG. 5B, a sealant 231 is applied to the peripheral portion, the lower portion of the drive IC 221, and the surface where the hydrophobic film 230 is not formed. At this time, since a part of the installation surface of the drive IC 221 is subjected to lyophobic treatment, the sealant 231 is not applied to a part of the installation surface of the drive IC 221. Next, as shown in FIG. 3C, a heat radiating member 232 for radiating heat generated by the heat generated by the drive IC 221 is provided in close contact with the installation surface of the drive IC 221. The width of the flat surface portion of the heat radiating member 232, that is, the surface closely contacting the installation surface of the drive IC 221 (indicated by W3 in FIG. 5) is narrower than the entire width of the installation surface of the drive IC 221 (indicated by W4 in FIG. 5). It has become. As a result, the heat generated by the driving IC 221 can be effectively radiated from the heat radiating member 232. Then, as shown in FIG. 4D, a sealant 231 is applied so as to cover a part other than the part (exposed part to the space) of the heat radiating member 232 so that part of the heat radiating member 232 is exposed. To do. The heat dissipating member 232 is preferably made of a material having high thermal conductivity such as copper or aluminum. Further, since the width W3 of the flat surface portion of the heat radiation member 232 is narrower than the entire width W4 of the installation surface of the drive IC 221 (W3 <W4), the flat surface portion of the heat radiation member 232 is in close contact with at least the installation surface of the drive IC 121.

  FIG. 6 is a process cross-sectional view illustrating a process of installing a heat radiating member in a droplet discharge head according to a second modification of the present embodiment. In the figure, the same reference numerals as those in FIG. 4 denote the same components. As shown in FIG. 6A, a hydrophobic film 230 is formed continuously on a part of the installation surface of the heat radiation member opposite to the joint surface connected to the wiring substrate of the driving IC 221 and a substantially vertical surface (side surface). It is formed. Then, as shown in FIG. 5B, a sealant 231 is applied to the peripheral portion and the lower portion of the drive IC 221. At this time, since the lyophobic treatment is performed on the installation IC and a part of the side surface of the drive IC 221, the sealant 231 is not applied to the installation surface and part of the side surface of the drive IC 221. Next, as shown in FIG. 3C, a heat radiating member 232 for radiating heat generated by the heat generated by the drive IC 221 is provided in close contact with the installation surface of the drive IC 221. The width of the flat portion of the heat radiating member 232 (indicated by W5 in FIG. 6) is wider than the width of the region subjected to the lyophobic treatment (indicated by W6 in FIG. 6) on the installation surface of the drive IC 221. Then, as shown in FIG. 4D, a sealant 231 is applied so as to cover a part other than the part (exposed part to the space) of the heat radiating member 232 so that a part of the heat radiating member 232 is exposed. To do. As a result, the heat generated by the driving IC 221 can be effectively radiated from the heat radiating member 232. Further, since the width W5 of the flat surface portion of the heat radiating member 232 is wider than the width W6 of the lyophobic region of the driving IC 221 (W5> W6), the flat surface portion of the heat radiating member 232 is in close contact with all the surfaces of the installation surface of the driving IC 221. doing.

  FIG. 7 is a process cross-sectional view illustrating a process of installing a heat radiating member in a droplet discharge head as a third modification of the present embodiment. In the figure, the same reference numerals as those in FIG. 4 denote the same components. As shown in FIG. 6A, a hydrophobic film 230 is formed continuously on a part of the installation surface of the heat radiation member opposite to the joint surface connected to the wiring substrate of the driving IC 221 and a substantially vertical surface (side surface). It is formed. Then, as shown in FIG. 5B, a sealant 231 is applied to the peripheral portion and the lower portion of the drive IC 221. At this time, since the lyophobic treatment is performed on the installation IC and a part of the side surface of the drive IC 221, the sealant 231 is not applied to the installation surface and part of the side surface of the drive IC 221. Next, as shown in FIG. 3C, a heat radiating member 232 for radiating heat generated by the heat generated by the drive IC 221 is provided in close contact with the installation surface of the drive IC 221. The width of the planar portion of the heat radiating member 232 (indicated by W7 in FIG. 7) is narrower than the width of the region subjected to the lyophobic treatment (indicated by W8 in FIG. 7) on the installation surface of the drive IC 221. Then, as shown in FIG. 4D, a sealant 231 is applied so as to cover a part other than the part (exposed part to the space) of the heat radiating member 232 so that a part of the heat radiating member 232 is exposed. To do. As a result, the heat generated by the driving IC 221 can be effectively radiated from the heat radiating member 232. Further, since the width W7 of the flat surface portion of the heat radiating member 232 is narrower than the width W8 of the lyophobic region of the drive IC 221 (W7 <W8), the flat surface portion of the heat radiating member 232 is in close contact with at least the installation surface of the drive IC 221. .

  In the embodiment described above, the case where the pressure generating element is an electromechanical conversion element has been described, but an electrothermal conversion element may be used. Further, although the case of an ink jet head integrated with four colors has been described, the same effect can be obtained even in the case of an ink jet head integrated with two colors.

What has been described above is merely an example, and the present invention has a specific effect for each of the following modes.
(Aspect A)
A lyophobic treatment is performed on an adhesive portion that adheres to the adhesive surface of the heat dissipation member on the outer surface of the drive element facing the adhesive surface of the heat dissipation member. According to this, as described in the above embodiment, even if the sealing agent 231 for protecting the drive IC 221 is applied before the heat dissipation member 232 is bonded to the outer surface of the drive IC 221, the heat dissipation member 232 is connected to the drive IC 221. If the lyophobic treatment is applied to the outer surface of the driving IC 221 to be bonded to the bonding surface of the heat radiating member 232 before bonding to the outer surface, the sealant 231 does not enter the bonding portion. . As a result, the adhesive surface of the heat dissipation member 232 and the outer surface of the drive IC 221 facing the adhesive surface are in direct contact with each other without the sealant 231 interposed therebetween, and the heat dissipation effect of the heat dissipation member 232 is prevented from being lowered. be able to. Therefore, it is possible to provide a droplet discharge head that can reduce the influence of heat due to heat generated by the drive IC 221 provided in the vicinity of the pressurized liquid chamber and can reduce variations in droplet discharge characteristics.
(Aspect B)
In (Aspect A), the longitudinal width of the outer surface of the lyophobic driving element is substantially the same as or wider than the longitudinal width of the bonding surface of the heat dissipation member. According to this, as described in the above embodiment, the first modified example, the second modified example, and the third modified example, the adhesive portion between the adhesive surface of the heat radiating member 232 and the outer surface of the drive IC 221 is sealed. Stopper 231 cannot penetrate. Thereby, the heat dissipation effect from the heat radiating member 232 is not lowered.
(Aspect C)
In (Aspect A) or (Aspect B), a lyophobic treatment is performed on the entire or central portion of the outer surface of the drive element where there is a contact point with the heat radiating member. According to this, as described in the above embodiment and the first modification, the sealant 231 cannot enter the bonded portion between the bonding surface of the heat dissipation member 232 and the outer surface of the drive IC 221. Thereby, the heat dissipation effect from the heat radiating member 232 is not lowered.
(Aspect D)
In (Aspect A), the pressure generating element is an electromechanical conversion element. According to this, since the heat dissipation effect of the heat radiating member does not decrease as described in the above embodiment, the influence of heat on the liquid in the pressurized liquid chamber is reduced. Thereby, it does not change from the droplet discharge characteristic by raising the internal pressure of the pressurized liquid chamber due to the deformation displacement of the electromechanical transducer.
(Aspect E)
The liquid droplet ejection head according to any one of (Aspect A) to (Aspect D) is provided. According to this, as described in the above embodiment, the heat radiation effect of the heat radiating member is not reduced, so that the influence of heat on the ink in the pressurized liquid chamber is reduced. Accordingly, it is possible to provide a droplet discharge device that can reduce variations in droplet discharge characteristics and can perform stable droplet discharge.
(Aspect F)
The recording liquid is discharged onto a recording medium using the droplet discharge head according to any one of (Aspect A) to (Aspect D). According to this, as described in the above embodiment, the heat radiation effect of the heat radiating member is not reduced, so that the influence of heat on the ink in the pressurized liquid chamber is reduced. Thus, the recording liquid droplet discharge characteristics are not changed, and stable recording liquid droplet discharge can be performed.
(Aspect G)
The ink jet head of (Aspect F) is provided. According to this, as described in the above embodiment, the heat radiation effect of the heat radiating member is not reduced, so that the influence of heat on the ink in the pressurized liquid chamber is reduced. As a result, it is possible to provide an image forming apparatus capable of forming a high-quality image by discharging droplets of the recording liquid stably without changing the discharge characteristics of the recording liquid.

DESCRIPTION OF SYMBOLS 100 Inkjet recording apparatus 200 Inkjet head 201 Head part 202 Nozzle 203 Nozzle plate 204 Restrictor 205 Individual flow path 206 Individual flow path plate 207 Vibration plate 208 Individual electrode 209 Pressure generating element 210 Common electrode 211 Insulating layer 212 Support member 213 Common flow path Forming member 214 common channel forming member 215 common channel forming member 216 common channel forming member 217 common channel 218 common channel 219 common channel 220 common channel 221 driving IC
222 Solder ball 223 Solder ball 224 Heat dissipation member 225 Sealant 230 Hydrophobic film 231 Sealant 232 Heat dissipation member

JP 2004-327556 A

Claims (7)

A nozzle plate provided with a nozzle for discharging liquid droplets, a liquid chamber plate joined to the nozzle plate and containing at least a pressurized liquid chamber for containing a liquid therein, and an internal pressure in the pressurized liquid chamber A pressure generating element that raises the pressure and discharges the liquid from the nozzle; and a driving element that supplies a droplet discharge signal to the pressure generating element; and a heat dissipation member is bonded to the outer surface of the driving element having a substantially flat plate shape, In the droplet discharge head that discharges heat generated by the heat generated by the drive element to the outside via the heat dissipation member,
A liquid droplet ejection head, wherein a lyophobic treatment is performed on an adhesive portion that adheres to an adhesive surface of the heat radiating member on an outer surface of the drive element facing the adhesive surface of the heat radiating member. The droplet discharge head according to claim 1,
The droplet discharge head according to claim 1, wherein a width in the longitudinal direction of the outer surface of the drive element subjected to the lyophobic treatment is substantially the same as or wider than a width in the longitudinal direction of the adhesive surface of the heat radiating member. The droplet discharge head according to claim 1 or 2,
A liquid discharge head, wherein a lyophobic treatment is performed on all or a central portion of the outer surface of the drive element where the contact point with the heat radiating member is located. The droplet discharge head according to claim 1,
The droplet discharge head, wherein the pressure generating element is an electromechanical conversion element.   A droplet discharge apparatus comprising the droplet discharge head according to claim 1.   An ink jet head that discharges a recording liquid onto a recording medium using the droplet discharge head according to claim 1.   An image forming apparatus comprising the inkjet head according to claim 6.

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