JP2013006297A - Method for manufacturing inkjet head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing an inkjet head capable of preventing inflow into an ink flow path side even when a thermosetting composition provided between flow path members comprising an ink flow path is fluidized following rising temperature during heat curing.SOLUTION: The method includes: a step of forming a thermosetting composition, which arranges flow path members 3 and 1 at a predetermined mutual joint position, and forms the thermosetting composition C between joint surfaces 31c and 12a of the flow path members 3 and 1 from the ink flow path side to an external air side; and a step of heating which bonds between the flow path members 3 and 1 by heating and curing the thermosetting composition C afterwards, and seals the ink flow path between the flow path members 3 and 1. The thermosetting composition C is formed of the thermosetting composition which is temporarily fluidized following rising temperature by heating in the step of heating, and is irreversibly cured. In the step of heating, the pressure at the ink flow path side is held higher than the pressure at the external air side when the thermosetting composition is at least fluidized in the step of heating.

Description

  The present invention relates to a method for manufacturing an ink jet head, and more particularly to a method for manufacturing an ink jet head that prevents clogging of an ink flow path by a thermosetting composition that bonds between flow path members constituting the ink flow path.

  Conventionally, as an inkjet head, a manifold for supplying ink to the channel and a nozzle for discharging ink from the channel are formed on a head chip provided with a channel for applying discharge pressure to the ink. There are known ones obtained by adhering a nozzle plate.

  Patent Document 1 describes a technique for forming an adhesive portion for bonding a manifold and a head chip by thermally curing a thermosetting composition.

  On the other hand, in Patent Document 2, an elastic adhesive is bonded to a head chip and a nozzle plate using an epoxy-based elastic adhesive, and the elastic adhesive is protected by a protective layer so that the elastic adhesive can be used for humidity and gas components of outside air. It is prevented from reacting with and deteriorating.

  Patent Document 3 discloses a fluorine-based rubber composition exhibiting thermosetting properties, which includes a polymer having a fluorinated polyether skeleton in the main chain as a main component. Furthermore, Patent Document 4 describes that such a composition is mixed with silica treated with a surface treatment agent to improve the viscosity.

JP 2006-291167 A JP 2003-326708 A JP-A-9-95615 JP 2006-52386 A

  The thermosetting composition is cured by crosslinking between the polymers by heating, thereby exhibiting adhesiveness.

  This process will be described in further detail. Generally, the thermosetting composition generally tends to decrease in viscosity from the start of heating (usually room temperature) until reaching a certain temperature (curing start temperature). This is because the movement of the polymer is activated by thermal energy. When the heating is further continued and the temperature of the thermosetting composition exceeds the curing start temperature, a cross-linking reaction between the polymers starts and the viscosity increases irreversibly. That is, curing is started.

  As described above, the thermosetting composition is cured through a low viscosity state, that is, a fluidized state, so that it wets and spreads when fluidized, and the heat applied between the manifold and the head chip. There has been a problem that the curable composition easily flows into a channel provided in a narrow width on the head chip due to a capillary phenomenon. In particular, when the amount of the thermosetting composition applied is increased in order to reliably seal the ink outflow from between the manifold and the head chip, the inflow is more likely to occur.

  On the other hand, a stress caused by a difference in linear expansion coefficient between the two members acts on the bonding portion connecting the manifold and the head chip due to a temperature change. Specifically, for example, residual stress at the time of heat bonding, stress accompanying heating / cooling of ink or the like.

  When an adhesive having a high hardness is used against these stresses, the stress cannot be absorbed, so that distortion occurs between the two members, and the ink ejection accuracy may be lowered.

  Therefore, the present inventor examined using an elastic adhesive, but a general elastic adhesive is easily swelled or eluted by humidity, solvent, acid or basic ink, and a manifold and a head chip. It has been difficult to use it in places where it directly touches the outside air or ink, such as an adhesive part connecting the two.

  For example, as in Patent Document 2, even if the elastic adhesive is protected from the outside air by the protective layer, the epoxy-based elastic adhesive is difficult to obtain durability with respect to the solvent, acid or basic ink. . Providing the protective layer also complicates the process and causes a problem of reducing productivity.

  As a result of searching for an elastic adhesive particularly suitable for bonding between a manifold and a head chip in an inkjet head, the present inventor has found that a fluorine-based rubber composition exhibiting thermosetting properties, particularly preferably a fluorinated polyether skeleton. It has been found that a thermosetting composition containing as a main component a polymer having excellent resistance to humidity, a solvent, and an ink exhibiting acidity or basicity.

  However, the fluorine-based rubber composition exhibiting thermosetting property is relatively fluidized as the temperature rises during heat curing, and as described above, it is applied between the manifold and the head chip during the temperature raising process. It has been found that the problem of the thermosetting composition flowing into the channel becomes significant. As described in Patent Document 4, it has been found that even if silica treated with a surface treatment agent is blended to improve viscosity, there is a limit in preventing inflow.

  When the thermosetting composition flows into the channel, the ink flow path is blocked by the adhesive, resulting in ink ejection failure. It is extremely difficult to remove the thermosetting composition that has flowed into the ink flow path, and there is a strong demand for a technique that prevents such inflow.

  Further, not only in the case of bonding between the manifold and the head chip, but also in the case where the flow path members constituting the ink flow path are bonded through the thermosetting composition, the temperature rises during heating. The inflow of the fluidized thermosetting composition tends to cause a problem that the ink flow path is blocked.

  Therefore, an object of the present invention is to allow the thermosetting composition provided between the flow path members constituting the ink flow path to flow into the ink flow path side even when fluidized as the temperature rises during heat curing. An object of the present invention is to provide a method of manufacturing an ink jet head that can prevent the above.

  Other problems of the present invention will become apparent from the following description.

  The above problems are solved by the following inventions.

According to the first aspect of the present invention, the two flow path members constituting the ink flow path are arranged at a predetermined bonding position with each other, and heat is applied from the ink flow path side to the outside air between the bonding surfaces of the two flow path members. A thermosetting composition part forming step for forming a curable composition part;
After the thermosetting composition portion forming step, the thermosetting composition portion is heated and cured to bond the two flow path members, and the ink between the two flow path members. A heating step for sealing the flow path,
The thermosetting composition part is formed from a thermosetting composition that irreversibly cures after temporarily fluidizing with a temperature rise due to the heating in the heating step,
In the heating step, when the thermosetting composition is at least fluidized, the pressure on the ink flow path side is maintained higher than the pressure on the outside air side. .

  The invention according to claim 2 is characterized in that, in the heating step, the pressure on the ink flow path side is maintained higher than the pressure on the outside air side by flowing a fluid into the ink flow path. 1 is a method for producing an inkjet head according to item 1.

  According to a third aspect of the present invention, in the heating step, the fluid continues to flow into the ink flow path from one of the two flow path members and through the ink flow path. 3. The ink jet head manufacturing method according to claim 2, wherein the pressure on the ink flow path side is kept higher than the pressure on the outside air side by continuing to discharge the fluid from the other flow path member.

  According to a fourth aspect of the present invention, in the heating step, the other flow path member is provided with a nozzle plate in advance, and the fluid is continuously discharged through the nozzles of the nozzle plate. 3. A method for producing an ink jet head according to item 3.

  A fifth aspect of the present invention is the method of manufacturing an ink jet head according to any one of the second to fourth aspects, wherein the fluid is air or nitrogen gas.

  The invention according to claim 6 is characterized in that the heating of the thermosetting composition part is performed by making the temperature of the fluid flowing into the ink flow path different from the temperature of the outside air. Item 6. The method for producing an inkjet head according to any one of Items 2 to 5.

  According to a seventh aspect of the present invention, the temperature of the fluid that flows into the ink flow path is lower than the curing start temperature of the thermosetting resin, and the temperature of the outside air is equal to or higher than the curing start temperature of the thermosetting resin. The method of manufacturing an ink jet head according to claim 6, wherein the heating of the thermosetting composition part is performed by the outside air.

  The invention according to claim 8 is the method of manufacturing an ink jet head according to claim 7, wherein the temperature of the fluid flowing into the ink flow path is room temperature.

  According to a ninth aspect of the present invention, the temperature of the fluid that flows into the ink flow path is equal to or higher than the curing start temperature of the thermosetting resin, and the temperature of the outside air is less than the curing start temperature of the thermosetting resin. The method of manufacturing an ink jet head according to claim 6, wherein the heating of the thermosetting composition portion is performed by the fluid.

  The invention according to claim 10 is the method of manufacturing an ink jet head according to claim 9, wherein the temperature of the outside air is room temperature.

  The invention according to claim 11 is characterized in that, in the heating step, the pressure on the ink flow path side is set within a range in which the shape of the thermosetting composition portion previously formed in the thermosetting composition portion forming step is maintained. The method for manufacturing an ink jet head according to claim 1, wherein the pressure is maintained higher than the pressure on the outside air side.

  The invention according to claim 12 is characterized in that, in the thermosetting composition portion forming step, the thermosetting composition portion formed between the joint surfaces of the two flow path members is formed between the joint surfaces facing each other. It has a fillet part which protrudes, It is a manufacturing method of the ink-jet head in any one of Claims 1-11 characterized by the above-mentioned.

  According to a thirteenth aspect of the invention, the fillet portion is formed so as to protrude from the joint surfaces facing each other to the ink flow path side. It is.

  According to a fourteenth aspect of the present invention, one of the two flow path members includes a head chip having a pressure chamber for applying a discharge pressure to the ink. The pressure chamber is open at the joint surface of the passage member, and the thermosetting composition portion formed between the joint surface of the other flow path member surrounds the opening of the pressure chamber. The method of manufacturing an ink jet head according to claim 1, wherein the ink jet head is formed as follows.

  According to a fifteenth aspect of the present invention, the other flow path member includes a manifold, and the manifold forms the joint surface of the other flow path member. It is a manufacturing method of a head.

  The invention according to claim 16 is characterized in that, in the thermosetting composition portion forming step, after the other flow path member is arranged at a predetermined bonding position with respect to the one flow path member, the space between the bonding surfaces is set. The method according to claim 15, wherein the thermosetting composition portion is formed by attaching the thermosetting composition from the outside air side.

  The invention according to claim 17 is the thermosetting composition part forming step, wherein after the thermosetting composition is attached to the manifold provided in the other flow path member, the other flow path member is After being disposed at a predetermined joining position with respect to one flow path member, and sandwiching the thermosetting composition with the joint surface of the one flow path member, further, between the joint surfaces 16. The method of manufacturing an ink jet head according to claim 15, wherein the thermosetting composition portion is formed by attaching an additional thermosetting composition from the outside air side.

  The invention according to claim 18 is characterized in that the thermosetting composition is a fluorine-based rubber composition exhibiting thermosetting properties. It is.

  The invention according to claim 19 is characterized in that the thermosetting fluorinated rubber composition contains as a main component a polymer having a fluorinated polyether skeleton in the main chain. It is a manufacturing method of a head.

According to a twentieth aspect of the invention, the fluorinated polyether skeleton is a perfluoropolyether repeating unit (—C _a F _{2 × a} O— [a is an integer in the range of 1 to 6]]. The inkjet head manufacturing method according to claim 19, wherein the inkjet head is a perfluoropolyether skeleton containing an integer number of times in the range of 20 to 600.

  The invention according to claim 21 is the manufacture of an ink jet head according to any one of claims 1 to 20, wherein the thermosetting composition has a curing start temperature in a range of 40 ° C to 120 ° C. Is the method.

  The invention according to claim 22 is characterized in that the thermosetting composition contains 1 to 30 parts by weight of finely divided silica surface-treated with a surface treatment agent. A method for producing an inkjet head according to any one of the above.

  The invention according to claim 23 is the method of manufacturing an ink jet head according to claim 22, wherein the surface treatment agent is a silane-based surface treatment agent.

  According to the present invention, the thermosetting composition provided between the flow path members constituting the ink flow path is prevented from flowing into the ink flow path side even when fluidized as the temperature rises during heat curing. An inkjet head manufacturing method that can be provided can be provided.

The perspective view which shows the longitudinal cross-section of an example of the inkjet head obtained by the manufacturing method of the inkjet head which concerns on this invention Sectional drawing which shows the 1st aspect of a thermosetting composition part formation process. Sectional drawing which shows the 2nd aspect of a thermosetting composition part formation process. Sectional drawing explaining an example of a heating process The figure which shows an example of the viscosity change of the thermosetting composition part accompanying the elapsed time at the time of heat-curing The figure which shows the other example of the viscosity change of the thermosetting composition part accompanying the elapsed time at the time of heat-curing Plan view of FIG. Sectional drawing which shows the other example of the inkjet head obtained by the manufacturing method of the inkjet head which concerns on this invention Sectional drawing which shows the further another example of the inkjet head obtained by the manufacturing method of the inkjet head which concerns on this invention. Sectional drawing which shows an example between the flow path members which can be adhere | attached with the manufacturing method of the inkjet head which concerns on this invention

  The ink jet head to which the ink jet head manufacturing method according to the present invention can be applied is specific as long as it includes at least two flow path members that form an ink flow path by being bonded to each other. Any structure is acceptable.

  For example, a large number of channels and a large number of partition walls formed in a groove shape are alternately arranged, and at least a part of the partition walls is formed of a piezoelectric material. An inkjet head having a structure for applying pressure for ejecting ink from nozzles, and a wall of a pressure chamber containing ink as a vibration plate, a piezoelectric material is laminated on the vibration plate, and mechanical deformation of the piezoelectric material An ink-jet head having a structure for applying pressure for ejecting ink in the pressure chamber from the nozzle by vibrating the diaphragm by the operation, an electrothermal conversion element disposed in the pressure chamber containing the ink, Bubbles are generated by heating the ink by energization, and pressure is applied to discharge the ink in the pressure chamber from the nozzles by the bursting action of the bubbles. To have an ink-jet head or the like of the structure, the present invention can also be applied to the production of any of the ink jet head.

  In the present invention, the ink flow path refers to an ink supply path inside such an ink jet head, and specifically, from an ink supply pipe through which ink is supplied into the ink jet head to each channel or each pressure chamber. On the other hand, it refers to a flow path of ink formed through an ink chamber for supplying ink in common to each channel or each pressure chamber and further from each channel or each pressure chamber to each nozzle.

  In the present invention, the flow path member is a member constituting the wall surface of the ink flow path in contact with the ink flow path in the ink jet head. Specifically, the ink supply pipe and the ink chamber are formed. For example, a member (hereinafter referred to as a manifold), a head chip having a channel or a pressure chamber, a nozzle plate on which nozzles are formed, and the like can be exemplified. In terms of the head chip, each of the substrate constituting the channel or the pressure chamber and the substrate forming the wall surface of the channel or the pressure chamber can be regarded as one flow path member.

  In the present invention, in order to form an ink flow path, such two flow path members are bonded using a thermosetting composition, and the ink flow path is sealed between the flow path members. It is suitably applied to.

  Hereinafter, an example of the manufacturing method of the ink jet head according to the present invention will be described. Here, as the inkjet head, a large number of channels and a large number of partition walls formed in a groove shape are alternately arranged, and at least a part of the partition walls is formed of a piezoelectric material, and the partition walls are deformed by the piezoelectric effect. Thus, an ink jet head having a structure for applying pressure for ejecting ink in a channel from a nozzle will be described as an example.

  FIG. 1 is a perspective view showing an inkjet head in a longitudinal section.

  In FIG. 1, H1 is an ink-jet head, and the ink-jet head H1 is formed by integrally joining a head chip 1, a nozzle plate 2, and a manifold 3.

  The head chip 1 includes a channel substrate 11 and a cover substrate 12.

  The channel substrate 11 includes channels 110 that are pressure chambers for applying discharge pressure to the ink and partition walls 111 alternately.

  Here, the partition 111 made of a piezoelectric material such as PZT is driven in response to an electric signal so that an ejection pressure for ejecting ink into the channel 110 is generated.

  The cover substrate 12 is laminated on the upper surface of the channel substrate 11 so as to cover the channel 110.

  The cover substrate 12 includes an opening 120. The channel 110 forms a channel inlet 110 a for introducing ink into the channel 110 at the position of the opening 120 of the cover substrate 12.

  On the other hand, the channel 110 forms a channel outlet 110 b for discharging ink on the front surface of the head chip 1.

  The nozzle plate 2 includes nozzles 21 for ejecting ink. The nozzle 21 is provided adjacent to the channel outlet 110b.

  In this way, when an ejection pressure is applied to the ink in the channel 110, the pressurized ink is ejected from the nozzle 21 via the channel outlet 110b.

  The manifold 3 includes a box-shaped manifold main body 31 composed of an upper wall 31a and a side wall 31b, an ink chamber 32 in the manifold main body 31, and an ink supply port 33 for supplying ink into the ink chamber 32. I have. An ink supply pipe 34 is connected to the ink supply port 33 and supplies ink into the ink chamber 32 through the ink supply port 33.

  The manifold 3 is bonded to the head chip 1 so as to cover the ink introduction port 110 a exposed from the opening 120 of the cover substrate 12. Here, in the manifold 3, the entire end surface 31 c which is an adhesive surface is bonded to the upper surface 12 a of the cover substrate 12. Thereby, ink is supplied from the upper surface side of the head chip 1 to the channel 110 through the ink introduction port 110a.

  Here, as two flow path members, a head chip 1 having a large number of channels 110 and a manifold 3 forming an ink chamber 32 for supplying ink in common to the channels 110 are thermally cured. The case where it adhere | attaches using an adhesive composition is demonstrated.

  In FIG. 1, B is an adhesive portion that bonds the manifold 3 and the head chip 1, each of which is a flow path member, and at the same time, has a function of sealing ink outflow from between the manifold 3 and the head chip 1. is doing.

  The adhesion part B is formed by heat-curing a thermosetting composition.

  First, the 1st aspect of the thermosetting composition part formation process for forming the adhesion part B using a thermosetting composition is demonstrated with reference to FIG.

  As shown in FIG. 2A, in the first aspect of the thermosetting composition portion forming step, first, the manifold 3 is positioned and arranged at a predetermined bonding position on the head chip 1.

  Next, as shown in FIG. 2B, the thermosetting composition is applied from the outside of the manifold 3 so as to satisfy the corners of the upper surface 12 a of the cover substrate 12 and the outer surface of the side wall 31 b outside the manifold 3. The applied thermosetting composition permeates between the end surface 31c of the manifold 3 and the upper surface 12a of the cover substrate 12 by capillary action.

  Further, a part of the applied thermosetting composition has a surface extending from the upper surface 12a of the cover substrate 12 to the outer surface of the side wall 31b so as to satisfy an angle between the upper surface 12a of the cover substrate 12 and the outer surface of the side wall 31b. A smooth curved surface is formed. In this specification, the portion Cf of the thermosetting composition that protrudes between the joint surfaces facing each other, that is, between the end surface 31c of the manifold 3 and the upper surface 12a of the cover substrate 12 is defined as the fillet portion. Called.

  In this manner, the thermosetting composition portion C is formed in the gap between the manifold 3 and the head chip 1 from the ink flow path side to the outside air side.

  When the thermosetting composition part C has the fillet part Cf, the pressure resistance against the ink pressure can be suitably imparted to the adhesive part B after the thermosetting composition part C is cured. That is, there is an effect that ink leakage from the gap between the manifold 3 and the head chip 1 can be more reliably sealed.

  In the 1st aspect of the above-mentioned thermosetting composition part formation process, there exists an effect which can form easily the fillet part Cf which protrudes to the outside air side between joining surfaces.

  Next, the 2nd aspect of a thermosetting composition part formation process is demonstrated with reference to FIG.

  As shown in FIG. 3A, in the second aspect of the thermosetting composition part forming step, before the manifold 3 is placed on the head chip 1, heat is applied in advance from the end surface 31c of the manifold 3 to the inner surface of the side wall 31b. A curable composition is applied.

  Next, as shown in FIG. 3 (b), the manifold 3 is positioned and arranged at a predetermined joining position on the head chip 1. At this time, since the thermosetting composition is applied in advance from the end surface 31c of the manifold 3 to the inner surface of the side wall 31b, the angle between the upper surface 12a of the cover substrate 12 and the inner surface of the side wall 31b on the ink chamber 32 side of the manifold 3 is obtained. The thermosetting composition is deformed to satisfy the above. The surface of the deformed thermosetting composition forms a smooth curved surface from the upper surface 12a of the cover substrate 12 to the inner surface of the side wall 31b. That is, a fillet portion Cf that protrudes from the joint surface to the ink flow path side is formed.

  Next, as shown in FIG. 3C, the thermosetting composition is applied from the outside of the manifold 3 so as to fill the corners of the upper surface 12 a of the cover substrate 12 and the outer surface of the side wall 31 b outside the manifold 3. The applied thermosetting composition permeates between the end surface 31c of the manifold 3 and the upper surface 12a of the cover substrate 12 by capillary action.

  Further, a part of the applied thermosetting composition has a surface extending from the upper surface 12a of the cover substrate 12 to the outer surface of the side wall 31b so as to satisfy an angle between the upper surface 12a of the cover substrate 12 and the outer surface of the side wall 31b. A smooth curved surface is formed. That is, a fillet portion Cf that protrudes between the joint surfaces to the outside air side is formed.

  In this manner, the thermosetting composition portion C is formed in the gap between the manifold 3 and the head chip 1 from the ink flow path side to the outside air side.

  In the second aspect of the thermosetting composition portion forming step, since the fillet portion Cf that protrudes from the joint surface to the ink flow path side can be easily formed, both sides between the joint surfaces can be combined with the fillet portion Cf that protrudes to the outside air side. It is easy to provide the fillet portions Cf and Cf.

  Since the thermosetting composition part C has the fillet parts Cf and Cf on both sides between the joining surfaces, the adhesive part B after the thermosetting composition part C is cured is more suitably resistant to ink pressure. Can be granted. That is, there is an effect that ink leakage from the gap between the manifold 3 and the head chip 1 can be sealed even more reliably.

  As explained in the first and second aspects of the thermosetting composition part forming step, when the thermosetting composition part C has a fillet part Cf, although it has excellent ink sealing properties, In the prior art, the problem that the thermosetting composition fluidized at the time of heat curing tends to flow into the ink flow path side increases. In particular, as described in the second embodiment, when the thermosetting composition portion C has a fillet portion Cf that protrudes to the ink flow path side, it easily flows into the ink flow path side.

  On the other hand, in the heating process performed after the thermosetting composition part forming process, even when the thermosetting composition part C includes the fillet part Cf, the thermosetting composition part formation is performed. The thermosetting composition part C can be cured while suitably maintaining the shape of the thermosetting composition part C formed in the process.

  In the following description, the thermosetting composition portion C is disposed in a state where the manifold 3 is aligned with a predetermined bonding position on the head chip 1 by the thermosetting composition portion forming step, and between the bonding surfaces. An assembly of the flow path members in a state where is formed may be referred to as an inkjet head precursor.

  Below, a heating process is demonstrated with reference to FIG.

  As shown in FIG. 4, in the heating step, the manifold 3 is arranged in a state where the manifold 3 is aligned with a predetermined bonding position on the head chip 1 by the previous thermosetting composition portion forming step, and the bonding surface The thermosetting composition part C is formed between them (inkjet head precursor). In the heating step, in this state, heating is started to cure the thermosetting composition part. In addition, the thing which has the fillet part Cf by a thermosetting composition in the both sides between joining surfaces is illustrated by the thermosetting composition part formation process which concerns on a 2nd aspect here.

  The heating means is not particularly limited as long as the thermosetting composition part C can be heated to the curing start temperature or higher, and for example, a baking furnace or the like can be preferably exemplified.

  In the present invention, in the heating step, the pressure on the ink flow path side is maintained higher than the pressure on the outside air side during heating.

  Thus, the manifold 3 and the head chip 1 are bonded together in a state where the pressure in the ink chamber 32 is maintained higher than the pressure on the outside air side. Here, the outside air side is the outside of the ink flow path, and refers to the space side that surrounds the manifold 3 and the head chip 1 from the outside. Specifically, the space in the baking furnace that houses the head chip 1 and the manifold 3 is used. And so on.

  In the illustrated example, the fluid in the ink chamber 32 is caused to flow so that the pressure in the ink chamber 32 becomes higher than the pressure on the outside air side.

  The fluid is not particularly limited, and a gas or a liquid can be used, but a gas is preferably used. If it is gas, elution of the thermosetting composition part C into the fluid can be suitably prevented, and there is no need to provide a drying step after the heating step.

  Although it does not specifically limit as gas, Air or inert gas, such as nitrogen and argon, can be illustrated preferably. In the case of using air, the effect of preventing wetting and spreading of the thermosetting composition part C can be obtained preferably by using dry air having a relative humidity of 30% or less.

  The flow path of the fluid into the ink chamber 32 is not particularly limited, and may be from the channel outlet 110b side or from the ink supply port 33. However, as shown in the drawing, the ink chamber 33 is connected to the ink chamber. Preferably, the fluid is allowed to flow into 32. Specifically, the fluid can be caused to flow into the ink chamber 32 through an ink tube (not shown) connected to the ink supply port 33.

  FIG. 5 is a diagram illustrating an example of a change in viscosity of the thermosetting composition portion with the elapsed time during heat curing.

  In the figure, the curve indicated by V indicates the viscosity change of the thermosetting composition part C.

  In the present invention, the thermosetting composition part C is cured by crosslinking between the polymers by heating, thereby forming an adhesive part B having adhesiveness.

  As described above, this process will be described in more detail. Generally, the thermosetting composition generally decreases in viscosity from the start of heating (usually room temperature) until reaching a certain temperature (curing start temperature). In other words, it tends to fluidize. This is because the movement of the polymer is activated by thermal energy. When the heating is further continued and the temperature of the thermosetting composition exceeds the curing start temperature, a cross-linking reaction between the polymers is started, and the viscosity increases irreversibly. That is, curing is started.

  That is, as shown by the curve V, the thermosetting composition exhibits a property of irreversibly curing after fluidizing temporarily with the elapsed time of heating.

  Therefore, according to the present invention, as described above, during the heating, the pressure on the ink flow path side is kept higher than the pressure on the outside air side, so that the thermosetting composition part C is heated in the temperature rising process during the heat curing. Since the pressure in the ink chamber 32 is higher than the pressure on the outside air side, the thermosetting composition portion is pressed from the ink chamber 32 side toward the outside air side to the ink flow path side. Therefore, inflow of the thermosetting composition into the channel 110 is prevented.

  In FIG. 5, the time for the thermosetting composition to reach the curing start temperature is indicated by Ts. That is, at the time Ts, the thermosetting composition has the lowest viscosity, that is, the most fluidized composition.

  In the present invention, it is preferable that the pressure on the ink flow path side is kept higher than the pressure on the outside air side at least near the time Ts after the start of heating. Furthermore, it is more preferable to keep the pressure on the ink flow path side higher than the pressure on the outside air side at least as long as the viscosity is equal to or lower than a predetermined value after the time Ts has elapsed after the start of heating. Alternatively, it is also preferable to keep the pressure on the ink flow path side higher than the pressure on the outside air side from the start of heating to the end of heating. In the cooling stage after the heating is finished, it is not always necessary to maintain the pressure on the ink flow path side higher than the pressure on the outside air side.

  In the present invention, the pressure difference between the pressure on the ink flow path side and the pressure on the outside air side is preferably a thermosetting composition in consideration of the viscosity of the thermosetting composition forming the thermosetting composition portion C. It is preferable to keep the pressure on the ink flow path side higher than the pressure on the outside air side within a range appropriately set so that the shape of the portion C can be maintained. Thereby, the effect which can block | close the ink flow path by the deformation | transformation and scattering of the thermosetting composition part C is acquired. Specifically, the injection pressure into the ink flow path is preferably in the range of 0.01 MPa to 0.20 MPa.

  In the present invention, it is preferable that the temperature of the fluid flowing from the ink supply port 33 has a temperature difference with respect to the temperature of the outside air. Thus, a difference in temperature rise timing can be provided between the thermosetting composition portion Cin on the ink chamber 32 side and the thermosetting composition portion Cout on the outside air side. This effect will be described below.

  FIG. 6 is a diagram showing another example of the viscosity change of the thermosetting composition portion with the elapsed time at the time of heat curing, in which the temperature of the fluid flowing from the ink supply port 33 is a temperature relative to the temperature of the outside air. It is a figure explaining the effect by having a difference.

  In the figure, a curve indicated by Vin indicates a change in viscosity of the thermosetting composition portion Cin on the ink chamber 32 side, and a curve indicated by Vout indicates a change in viscosity of the thermosetting composition portion Cout on the outside air side. Is shown.

  Here, a case where the temperature of the fluid flowing from the heated ink supply port 33 is lower than the temperature of the outside air will be described as an example.

  That is, since the temperature of the fluid flowing from the heated ink supply port 33 is lower than the temperature of the outside air, the temperature rise timing of the thermosetting composition portion Cin on the ink chamber 32 side is the thermosetting composition on the outside air side. A delay occurs with respect to the object part Cout.

  As a result, as shown in FIG. 6, the curve Vin changes in viscosity at a timing later than the curve Vout. That is, a low-viscosity state (fluidized state) is alternately formed at different timings between the thermosetting composition parts Cin and Cout. As a result, the thermosetting composition parts Cin and Cout are prevented from fluidizing all at once, and the shape of the thermosetting composition parts Cin and Cout, such as the layer thickness, is stabilized in the temperature rising process and spreads wet. And is prevented from flowing into the channel 110 by the fluidized thermosetting composition.

  In the above description, the case where the temperature of the fluid flowing from the ink supply port 33 is lower than the temperature of the outside air has been described as an example. However, in the present invention, the temperature of the fluid flowing from the heating ink supply port 33 is the outside air. It may be a case where the temperature is higher. That is, in any case, it is sufficient that the thermosetting composition parts Cin and Cout can be cured.

  For example, in the present invention, the temperature of the fluid flowing from the ink supply port 33 is less than the curing start temperature of the thermosetting composition, the temperature of the outside air is equal to or higher than the curing start temperature of the thermosetting composition, It is preferable to heat the thermosetting composition part C with outside air. At this time, the temperature of the fluid flowing from the ink supply port 33 is preferably room temperature.

  Alternatively, in the present invention, the temperature of the fluid flowing from the ink supply port 33 is equal to or higher than the curing start temperature of the thermosetting composition, and the temperature of the outside air is lower than the curing start temperature of the thermosetting composition, It is also preferable to heat the thermosetting composition part C with a fluid. At this time, the temperature of the outside air is preferably room temperature.

  Furthermore, in the present invention, it is more preferable to cure the thermosetting composition portion C by heating while replacing the fluid in the ink chamber 32 with a new fluid from the ink supply port 33. For example, as shown in FIG. 4, the fluid in the ink supply port 33 is caused to flow in and the fluid is discharged from the channel outlet 110 b side, whereby the fluid in the ink chamber 32 is changed to a new fluid from the ink supply port 33. Can be substituted. In the illustrated example, the fluid is discharged through the nozzle 21.

  By performing such replacement, even if the temperature of the outside air propagates into the ink chamber 32, the temperature difference between the fluid in the ink chamber 32 and the outside air can be suitably maintained. Thereby, there is an effect that the inflow of the thermosetting composition into the channel 110 is further prevented.

  In the present invention, the pressure formed in the ink chamber 32 can be mainly formed from two pressure elements. That is, the pressure depending on the pressure of the fluid itself and the flow velocity of the fluid.

  The pressure of the fluid itself is generated, for example, when the fluid itself is pressurized by a resistance received by the fluid in an ink flow path formed from the ink chamber 32 to the nozzle 21 through the channel 110. The pressure of the fluid itself can be formed even when the flow rate of the fluid is substantially zero by sealing the nozzle 21 with some sealing means, for example. Hereinafter, the pressure of the fluid itself may be referred to as static pressure.

  On the other hand, the pressure that depends on the flow rate of the fluid does not occur when the flow rate of the fluid is zero, but increases as the flow rate increases. That is, the pressure generated due to the kinetic energy of the fluid having mass. Hereinafter, the pressure depending on the flow rate of the fluid may be referred to as dynamic pressure.

  In the present invention, as long as the pressure in the ink chamber 32 can be higher than the pressure on the outside air side, it may be due to static pressure or due to dynamic pressure.

  Note that the fluid that has flowed in from the ink supply port 33 has a property of flowing in a direction in which it easily flows, and thus the flow velocity tends to vary depending on the location in the ink chamber 32. For this reason, if the ratio of the dynamic pressure to the static pressure in the ink chamber 32 is high, the pressure in the ink chamber 32 tends to become non-uniform. In addition, the dynamic pressure acts largely in the fluid flow direction and acts small in the direction orthogonal to the fluid flow direction. This also causes non-uniform pressure in the ink chamber 32.

  Therefore, from the viewpoint of pressing the fluidized thermosetting composition portion C, the flow rate of the fluid is decreased, and the pressure in the ink chamber 32 is made higher than the pressure on the outside air mainly by static pressure. preferable. Thereby, it is possible to make the pressure for pressing the thermosetting composition portion C exposed in the ink chamber 32 uniform over the entire circumference.

  However, in the present invention, from the viewpoint of not only pressing the fluidized thermosetting composition portion C but also ensuring the temperature difference between the fluid in the ink chamber 32 and the outside air as described above. It is preferable to replace the fluid in the ink chamber 32 while maintaining a certain flow rate in the fluid.

  In other words, in the present invention, it is preferable to increase the ratio of the static pressure to the fluid dynamic pressure and maintain a certain flow rate for fluid replacement in the ink chamber 32.

  In order to suitably realize this, in the present invention, it is preferable to cure the thermosetting composition part C by heating in a state where the nozzle plate 2 is attached to the head chip 1 in advance. That is, as shown in FIG. 4, it is preferable that the fluid flowing in from the ink supply port 33 is discharged through the nozzle 21 having a relatively small diameter.

  Here, the head chip 1 and the nozzle plate 2 may be attached in advance by bonding with an adhesive, or may be attached in advance by the adhesive force of the thermosetting composition before curing. Good. In order to obtain stability against the pressure from the fluid, it is preferable that the two are bonded in advance by an adhesive before the heating step. It is also preferable that the two are bonded in advance by curing the thermosetting composition.

  FIG. 7 is a plan view of FIG. 4, and is a diagram for explaining the effect of the fluid flowing in from the ink supply port 33 being discharged through the nozzle 21. As shown in FIG. 7, the plurality of channels 110 formed in the head chip 1 have a nozzle 21 at the channel outlet 110b.

  The nozzle 21 formed with a smaller diameter than the width of the channel 110 formed with a narrow width has a flow resistance against the fluid transferred from the channel 110, so the flow rate of the fluid flowing in from the ink supply port 33 Even in a state where the pressure is lowered, the fluid in the ink chamber 32 can be pressurized. That is, it is possible to increase the ratio of the static pressure to the dynamic pressure.

  Furthermore, since the flow velocity can be reduced, the range of variation in the flow velocity depending on the location in the ink chamber 32 can be reduced. As a result, an effect that the static pressure can be made uniform can be obtained.

  In particular, in the present invention, since the shapes of the nozzles 21 provided for each of the plurality of channels 110 are the same, resistance to the fluid is equally generated for each of the plurality of channels 110. As a result, the amount of fluid flowing into each channel 110 from the plurality of channel inlets 110a is made uniform. Thereby, the static pressure is further uniformized.

  As a result, the inside of the ink chamber 32 can be pressurized in a state where the pressure is made uniform over the entire inside of the ink chamber 32. Thereby, it becomes possible to equalize the pressure which presses this over the perimeter of the thermosetting composition part C accurately. That is, since a strong pressure can be prevented from acting locally on the thermosetting composition portion C, an effect of remarkably preventing the inflow of the thermosetting composition into the channel 110 can be obtained.

  Furthermore, simultaneously with these effects, the fluid in the ink chamber 32 is replaced by discharging the fluid from the nozzle 21, and a temperature difference between the fluid in the ink chamber 32 and the outside air is ensured. A low-viscosity state (fluidized state) is alternately formed between the composition parts Cin and Cout at different timings, and the inflow of the thermosetting composition into the channel 110 is further prevented.

  Further, since the head chip 1 includes the nozzle plate 2, pressurization is facilitated even if the flow rate is slowed down, so that the thermosetting composition part C is deformed or scattered by the collision of fluid. Can be prevented. As a result, the effect that the shape of the thermosetting composition part C can be suitably maintained in the shape formed in the thermosetting composition part forming step is obtained. In particular, when the thermosetting composition portion C includes the fillet portion Cf in the ink chamber 32, deformation and scattering are relatively likely to occur. Even in such a case, the head chip 1 includes the nozzle plate 2. Then, deformation and scattering can be suitably prevented.

  In the above description, the case where the manifold 3 is the ink-jet head H1 formed by being bonded only to the upper surface 12a of the cover substrate 12 of the head chip 1 has been described, but the ink-jet head obtained by the present invention is limited to this. It is not a thing.

  For example, as shown in FIG. 8, the manifold 3 is bonded across the upper surface 12 a of the cover substrate 12 and the upper surface 11 a of the piezoelectric substrate 11 so as to cover the channel inlet 110 a exposed from the end of the cover substrate 12. The present invention can also be preferably applied to the method of manufacturing the inkjet head H2, and the same effects as those of the inkjet head H1 described above can be obtained.

  Further, in the above description, an ink jet head of a type in which ink is supplied to the channel 110 from the direction intersecting the length direction of the channel 110 via the ink introduction port 110 a provided on the upper surface side of the head chip 1. Although the case of H1 or H2 has been described, for example, as shown in FIG. 9, it can be suitably applied to the case of manufacturing a so-called harmonica type inkjet head H3 in which ink is supplied along the length direction of the channel 110. The same effects as those of the ink jet head H1 or H2 described above can be obtained.

  That is, as shown in FIG. 9, in the harmonica type inkjet head H3, the channel inlet 110a is formed on the rear surface of the head chip 1.

  A wiring substrate 4 having an opening 40 is bonded to the rear surface of the head chip 1 at a position corresponding to the channel inlet 110a. The wiring board 40 includes wiring (not shown) for applying a driving potential for each channel 110.

  The manifold 3 is bonded to the upper surface 4 a of the wiring board 4 so as to cover the channel inlet 110 a exposed from the opening 40 of the wiring board 4. That is, the manifold 3 is bonded to the head chip 1 via the wiring board 4.

  Further, the flow path member to be bonded by the method of manufacturing an inkjet head of the present invention is not limited to the case of the manifold 3 and the head chip 1 described above.

  FIG. 10 is a cross-sectional view showing an example between flow path members that can be bonded by the method of manufacturing an inkjet head according to the present invention.

  In the illustrated example, the heating process is shown, and the two head chips 1 and 1 are arranged so that the back surfaces of the channel substrates 11 and 11 face each other. In addition, on the front surface of each head chip 1, 1 (surface oriented downward in the illustrated example), the nozzles 21 are provided one row at a position corresponding to each channel 110 row of both head chips 1, 1. A single nozzle plate 2 is arranged.

  For each head chip 1, 1, manifolds 3, 3 are arranged so as to cover the ink inlet 110 a.

  That is, in the illustrated example, an example of a method for manufacturing the inkjet head H4 including two rows of nozzles 21 is shown.

  Furthermore, 5 is a box-shaped housing for fixing and storing the inkjet head H4, and is made of, for example, aluminum.

  In the illustrated example, the thermosetting composition is previously formed not only between the manifold 3 and the head chip 1 but also between other flow path members in the former thermosetting composition portion forming step. .

  That is, first, in the drawing, C1 and C1 indicate thermosetting composition portions formed between the manifold 3 and the head chip 1.

  In this example, the thermosetting composition parts C <b> 1 and C <b> 1 are continuously formed from between the manifold 3 and the head chip 1 to between the manifold 3 and the inner surface of the housing 5. In other words, the thermosetting composition portions C1 and C1 are provided to bond the ink between the manifold 3 and the head chip 1 to seal the ink, and to fix the ink jet head H4 to the housing 5 for storage. ing.

  C2 indicates a thermosetting composition portion formed between the head chips 1 and 1 and the nozzle plate 2.

  C3 and C3 indicate thermosetting composition portions formed in the ink supply port 33 and the ink supply pipe 34 of the manifold 3.

  Further, C4 and C4 indicate thermosetting composition portions formed between the channel substrate 11 and the cover substrate 12 constituting the head chip 1.

  Heat curing of the thermosetting composition portions C1 to C4 provided between the flow path members may be performed after all the thermosetting composition portions C1 to C4 are formed in advance, or the head chip H4 is assembled. In this stage, a thermosetting composition portion is sequentially provided between one or two or more flow path members, and then heat-cured and bonded. By repeating this, all the thermosetting composition portions C1 to C1 are provided. C4 may be cured by heating.

  As described above, even in a case other than between the manifold 3 and the head chip 1, the pressure of the thermosetting composition portion C by heating is maintained in a state where the pressure on the ink flow path side is kept higher than the pressure on the outside air side. By performing the curing, an effect of preventing the thermosetting composition from flowing into the ink flow path side can be obtained.

  In particular, as shown in the figure, when the thermosetting composition portion C1 is continuously formed between the manifold 3 and the head chip 1 and between the manifold 3 and the housing 5, the thermosetting composition is used. However, according to the present invention, it is possible to suitably prevent the inflow even in such a case.

  Further, in the case of the harmonica type head chip H3 shown in FIG. 9, the adhesion between the head chip 1 and the wiring board 4 is the same as in the case of the thermosetting composition parts C1 to C4 described above. The present invention can be preferably applied, and the effect of preventing the thermosetting composition from flowing into the ink flow path side, particularly into the channel 110 can be obtained.

  In the present invention, the thermosetting composition is not particularly limited. However, as described above, the thermosetting composition can be cured as long as the thermosetting composition exhibits the property of being cured after being reduced in viscosity with increasing temperature. Can be remarkably obtained, which is preferable.

  By using a fluorine-based rubber composition exhibiting thermosetting as such a thermosetting composition, elasticity can be imparted to the cured adhesive layer, and further, humidity, solvent, acid / basic ink can be provided. It is preferable because it can impart resistance to.

  The fluorine-based rubber composition is not particularly limited, but the main component is a polymer having a fluorinated polyether skeleton in the main chain, and has excellent elasticity after curing, and humidity, solvent, acid / basic ink. It is particularly suitable because it can impart high resistance to the above.

As the fluorinated polyether skeleton, a perfluoropolyether repeating unit (—C _a F _{2 × a} O— [a is an integer in the range of 1 to 6]] is an integer in the range of 20 to 600. Preferred examples include perfluoropolyether skeletons repeatedly included. As a thermosetting composition mainly composed of a polymer having such a fluorinated polyether skeleton, commercially available products such as “SIFEL 2614” manufactured by Shin-Etsu Chemical Co., Ltd. and “X-71-6046” manufactured by Shin-Etsu Chemical Co., Ltd. Etc. "can be preferably used.

  The thermosetting composition has a cross-linking reactive group in the polymer, and thus heat-cures to develop adhesiveness. The crosslinking reactive group is not particularly limited as long as the polymers can be crosslinked by heating, and may include one or more of silicon-containing groups such as hydrosilyl groups and alkenyl groups such as vinyl groups. .

  In the present invention, the thermosetting composition is preferably one that cures at a high temperature in order to shorten the heat curing step. However, when cured at a high temperature, depolarization occurs in the piezoelectric material, and Performance decreases. Therefore, specifically, the curing start temperature is preferably in the range of 40 ° C. or higher and 120 ° C. or lower. Thereby, the time which a process requires can be shortened and the effect which improves productivity is acquired.

  In the present invention, a thermosetting composition having a curing start temperature of room temperature or lower can also be used. In this case, although not limited, for example, by allowing a cooling fluid below room temperature or a heating fluid above room temperature to flow into the ink flow path, the thermosetting composition is cured at room temperature, The present invention can be preferably applied.

  In the present invention, the thermosetting composition preferably contains finely divided silica in the range of 1 to 30 parts by weight. Thereby, the effect which prevents the wetting spread of a thermosetting composition part, a deformation | transformation, and scattering is acquired.

  As finely divided silica, those subjected to surface treatment can be preferably used. In particular, finely divided silica surface-treated with a silane-based surface treatment agent enhances the cohesive strength of the thermosetting composition, prevents deformation and scattering of the thermosetting composition portion, and enters the ink flow path. This has the effect of preventing the inflow.

  Examples of the present invention will be described below, but the present invention is not limited to such examples.

Example 1
<Thermosetting composition part formation process>
“SIFEL 2614” (manufactured by Shin-Etsu Chemical Co., Ltd.) as a thermosetting composition (mainly a polymer having a fluorinated polyether skeleton, the fluorinated polyether skeleton is (—C _a F _{2 × a} O— [a is 3 ]) Repeating unit of perfluoropolyether represented by 88), fine silica content: less than 1 part by weight, viscosity: 20 [Pa · s], curing start temperature: 100 ° C.) In accordance with the first aspect of the thermosetting composition portion forming step shown in FIG. 2, a thermosetting composition portion having a fillet portion on the outside air side is placed between the head chip on which the nozzle plate is previously attached and the manifold. The head chip precursor was obtained.

<Heating process>
As shown in FIG. 4, the obtained head chip precursor was placed in an oven maintained at 100 ° C., and 10 L of normal temperature (25 ° C.) air was supplied from the ink supply port of the manifold 3 into the ink flow path. Injection pressure at a flow rate of / min. While flowing at 0.1 MPa and discharging from the nozzle, the thermosetting composition was cured by heating for 4 hours to obtain an ink jet head.

[Evaluation method]
1. Emission test The obtained inkjet head was subjected to an emission test using a dummy ink for evaluation of emission that does not contain a coloring material (consisting of 90% by weight of 2-butoxyethyl acetate and 10% by weight of cyclohexanone). Each emission speed from a plurality of nozzles provided was measured.

1-1. Evaluation Criteria First, the head when the ejection speed from the plurality of nozzles included in the inkjet head has a maximum and minimum difference of 8% or less between the nozzles is determined to be acceptable, and the head when the difference exceeds the maximum is determined to be rejected. Judgment is performed for the obtained 10 inkjet heads.
A: 10 out of 10 heads passed.
○: Only 8 to 9 heads out of 10 pass.
Δ: Only 5 to 7 heads out of 10 pass.
X: Only less than 5 heads out of 10 pass.

2. Pressure / Leak Test Water was introduced by applying a pressure of 0.2 MPa from an ink supply port of a manifold provided in the obtained ink jet head, and water was allowed to flow out from all nozzle holes for 1 minute.

  Next, after water in the ink flow path was extruded and dried with air, an adhesive tape was attached to the nozzle plate to close all nozzle holes.

  Attach a syringe to the ink supply port via a rubber tube, pull the piston of the syringe to a scale of 5 ml, depressurize the inside of the flow path, release the piston, and check whether the syringe returns to the original position scale of 0 ml Then, the presence or absence of a leak was examined.

2-1. Evaluation criteria ○: No leak (the syringe returned to its original position)
X: Leakage occurred (the syringe did not return to the original position)

3. Solvent durability test An ink consisting only of N-methylpyrrolidinone (NMP) was introduced into the ink flow path of the obtained inkjet head.

  The ink supply port of the manifold was capped, and the nozzle plate was capped to close the nozzle, and stored in an oven at 60 ° C. for 1 month.

  One month later, the plug of the ink supply port and the lid of the nozzle plate were removed, water was introduced from the ink supply port at a pressure of 0.2 MPa, and water was allowed to flow out from all nozzle holes for 1 minute.

  Next, the water in the ink flow path was extruded with air and dried, and then an adhesive tape was applied to the nozzle plate to close all the nozzle holes.

  Attach a syringe to the ink supply port via a rubber tube, pull the piston of the syringe to a scale of 5 ml, depressurize the inside of the flow path, release the piston, and observe whether the syringe returns to the original position scale of 0 ml Then, the presence or absence of a leak was examined.

  The above operation was repeated 6 times until the storage period at 60 ° C. reached 6 months.

3-1. Evaluation criteria ◎◎: No leak until 6 months ◎: Leakage occurred at 6th month ○: Leakage occurred at 5th month △: Leakage occurred at 3rd to 4th month ×: Leakage occurred at 1st to 2nd month

  The above evaluation results are shown in Table 1.

(Example 2)
In Example 1, instead of the first mode of the thermosetting composition portion forming step, fillets are formed on both sides of the outside air side and the ink flow path side according to the second mode of the thermosetting composition portion forming step shown in FIG. An ink jet head was obtained in the same manner as in Example 1 except that a thermosetting composition part having a part was formed, and evaluated by the same evaluation method as in Example 1. The evaluation results are shown in Table 1.

(Example 3)
In Example 1, “X-71-6046” (manufactured by Shin-Etsu Chemical Co., Ltd.) (a polymer having a fluorinated polyether skeleton as a main component, the fluorinated polyether skeleton being (—C _a F _{2 × a 2} O— [a is 3])) perfluoropolyether repeating unit represented by 90 times, fine silica content: 5 parts by weight, viscosity: 220 [Pa · s], start of curing Temperature: 100 ° C.) and in place of the first mode of the thermosetting composition part forming step, according to the second mode of the thermosetting composition part forming step shown in FIG. An ink jet head was obtained in the same manner as in Example 1 except that a thermosetting composition part having a fillet part was formed on both sides on the ink flow path side, and evaluated by the same evaluation method as in Example 1. The evaluation results are shown in Table 1.

Example 4
In Example 1, instead of using “X-71-6046” manufactured by Shin-Etsu Chemical Co., Ltd. as the thermosetting composition, and instead of the first embodiment of the thermosetting composition part forming step, shown in FIG. According to the second aspect of the thermosetting composition portion forming step, the thermosetting composition portion having the fillet portions on both the outside air side and the ink flow path side is formed, and air is supplied as the fluid flowing from the ink supply port. An ink jet head was obtained in the same manner as in Example 1 except that nitrogen was used in place of, and evaluated by the same evaluation method as in Example 1. The evaluation results are shown in Table 1.

(Comparative Example 1)
In Example 1, an ink jet head was obtained in the same manner as in Example 1 except that air was not introduced from the ink supply port during heating, and evaluation was performed in the same evaluation method as in Example 1. The evaluation results are shown in Table 1.

(Reference Example 1) * Comparison of solvent durability In Example 1, 60% by weight of “Epicoat 807” (composition: bisphenol F type epoxy resin) manufactured by Japan Epoxy Resin and “Epicoat” manufactured by Japan Epoxy Resin as the thermosetting composition 152 ”(composition: phenol novolac epoxy resin) 40 wt% of an epoxy adhesive (viscosity: 25 [Pa · s], curing start temperature 40 ° C.) obtained by adding an imidazole curing agent was used. In addition, an ink jet head was obtained in the same manner as in Example 1 except that the temperature in the oven was set to 60 ° C. and air was not allowed to flow from the ink supply port during heating. The same solvent durability test was evaluated. The evaluation results are shown in Table 1.

(Reference Example 2) * Comparison of solvent durability In Example 1, as a thermosetting composition, "FE-61" (fluorinated silicone (fluorosilicone) made by Shin-Etsu Chemical Co., Ltd.) as a main component. Viscosity: 60 The ink jet head was obtained in the same manner as in Example 1 except that [Pa · s], curing start temperature: 100 ° C.) was used, and air was not allowed to flow from the ink supply port during heating. Evaluation was made in the same solvent durability test as in Example 1. The evaluation results are shown in Table 1.

(Reference Example 3) * Comparison of solvent durability In Example 1, “KE4895” (silicone adhesive, viscosity: 5 [Pa · s], room temperature curing type) manufactured by Shin-Etsu Chemical Co., Ltd. was used as the thermosetting composition. In addition, the ink jet head was obtained in the same manner as in Example 1 except that the curing was performed at room temperature and no air was allowed to flow from the ink supply port during the curing, and the same solvent as in Example 1 was obtained. It was evaluated by a durability test. The evaluation results are shown in Table 1.

<Evaluation>
From the results of the ejection test in Table 1, in Examples 1 to 4 in which the fluid was allowed to flow from the ink supply port during the heat curing, the ink ejection speed abnormality may occur compared to Comparative Example 1 in which the inflow was not performed. It can be seen that it is prevented. This shows that the flow of the thermosetting composition to the ink flow path side is suitably prevented.

  Further, in Examples 2 to 4 in which the thermosetting composition part having fillet parts on both the outside air side and the ink flow path side was formed according to the second aspect of the thermosetting composition part forming step, the solvent durability was excellent. I understand that.

  Furthermore, in Examples 3 and 4 in which the thermosetting composition is formulated with 5 parts by weight of finely divided silica, it is even better in the emission test than Examples 1 and 2 in which the amount of finely divided silica is less than 1 part by weight It can be seen that the results are correct.

  On the other hand, from Table 1, when comparing the solvent durability of Comparative Example 1 and Reference Examples 1 to 3 in which no fluid was introduced during heating, the polymer having a fluorinated polyether skeleton was the main component. In Comparative Example 1 using the thermosetting composition as described above, Reference Example 1 using another thermosetting composition (Reference Example 1: Epoxy, Reference Example 2: Fluorinated Silicone, Reference Example 3: Silicone) It can be seen that with respect to ˜3, the solvent durability is improved.

  According to the present invention, the solvent durability of the thermosetting composition mainly composed of a polymer having such a fluorinated polyether skeleton is utilized very effectively as shown in Examples 1 to 3. And the effect that the inflow of the thermosetting composition into the ink flow path can be remarkably prevented.

1: Head chip (channel member)
11: Channel substrate 110: Channel (pressure chamber, ink flow path)
110a: channel inlet 110b: channel outlet 12: cover substrate 12a: upper surface (bonding surface)
120: Opening (ink channel)
2: Nozzle plate 21: Nozzle 3: Manifold (channel member)
31: Manifold body 31a: Upper wall 31b: Side wall 31c: End face (joint face)
32: Ink chamber (channel member)
33: Ink supply port 34: Ink supply tube 4: Housing B: Adhesive part C: Thermosetting composition part H1-H4: Inkjet head

Claims (23)

The two flow path members constituting the ink flow path are arranged at predetermined joining positions with each other, and a thermosetting composition portion is formed between the joint surfaces of the two flow path members from the ink flow path side to the outside air side. A thermosetting composition part forming step;
After the thermosetting composition portion forming step, the thermosetting composition portion is heated and cured to bond the two flow path members, and the ink between the two flow path members. A heating step for sealing the flow path,
The thermosetting composition part is formed from a thermosetting composition that irreversibly cures after temporarily fluidizing with a temperature rise due to the heating in the heating step,
A method of manufacturing an ink jet head, wherein the pressure on the ink flow path side is maintained higher than the pressure on the outside air side when the thermosetting composition is in a fluidized state in the heating step.   2. The method of manufacturing an ink jet head according to claim 1, wherein, in the heating step, the pressure on the ink flow path side is maintained higher than the pressure on the outside air side by flowing a fluid into the ink flow path. .   In the heating step, the fluid continues to flow into the ink flow path from one of the two flow path members and from the other flow path member through the ink flow path. 3. The method of manufacturing an ink jet head according to claim 2, wherein the pressure on the ink flow path side is kept higher than the pressure on the outside air side by continuing to discharge the water.   4. The method of manufacturing an ink jet head according to claim 3, wherein, in the heating step, the other flow path member is provided with a nozzle plate in advance, and the fluid is continuously discharged through the nozzles of the nozzle plate. .   The ink jet head manufacturing method according to claim 2, wherein the fluid is air or nitrogen gas.   The temperature of the fluid flowing into the ink flow path and the temperature of the outside air are made different to perform the heating of the thermosetting composition part. The manufacturing method of the inkjet head of description.   The temperature of the fluid flowing into the ink flow path is lower than the curing start temperature of the thermosetting resin, the temperature of the outside air is equal to or higher than the curing start temperature of the thermosetting resin, and the thermosetting is performed by the outside air. The method of manufacturing an ink jet head according to claim 6, wherein the heating of the composition part is performed.   8. The method of manufacturing an ink jet head according to claim 7, wherein the temperature of the fluid flowing into the ink flow path is room temperature.   The temperature of the fluid flowing into the ink flow path is equal to or higher than the curing start temperature of the thermosetting resin, the temperature of the outside air is lower than the curing start temperature of the thermosetting resin, and the thermosetting is performed by the fluid. The method of manufacturing an ink jet head according to claim 6, wherein the heating of the composition part is performed.   10. The method of manufacturing an ink jet head according to claim 9, wherein the temperature of the outside air is room temperature.   In the heating step, the pressure on the ink flow path side is maintained higher than the pressure on the outside air side within a range in which the shape of the thermosetting composition portion previously formed in the thermosetting composition portion forming step is maintained. The method for manufacturing an ink jet head according to claim 1, wherein:   In the thermosetting composition part forming step, the thermosetting composition part formed between the joint surfaces of the two flow path members has a fillet part protruding from between the joint surfaces facing each other. The method for producing an ink jet head according to claim 1, wherein   13. The method of manufacturing an ink jet head according to claim 12, wherein the fillet portion is formed so as to protrude to the ink flow path side from between the joint surfaces facing each other.   Of the two flow path members, one of the flow path members includes a head chip having a pressure chamber for applying ejection pressure to the ink, and the joint surface of the one flow path member The pressure chamber is open, and the thermosetting composition portion formed between the joint surface of the other flow path member is formed so as to surround the opening of the pressure chamber. The manufacturing method of the inkjet head in any one of Claims 1-13.   15. The method of manufacturing an inkjet head according to claim 14, wherein the other flow path member includes a manifold, and the manifold forms the joint surface of the other flow path member.   In the thermosetting composition part forming step, after the other flow path member is disposed at a predetermined bonding position with respect to the one flow path member, the thermosetting from the outside air side between the bonding surfaces. The method of manufacturing an ink jet head according to claim 15, wherein the thermosetting composition portion is formed by adhering an adhesive composition.   In the thermosetting composition portion forming step, after the thermosetting composition is attached to the manifold included in the other channel member, the other channel member is attached to the one channel member. After being disposed at a predetermined bonding position and sandwiching the thermosetting composition with the bonding surface of the one flow path member, additional thermosetting is performed from the outside air side between the bonding surfaces. The method of manufacturing an ink jet head according to claim 15, wherein the thermosetting composition portion is formed by adhering an adhesive composition.   The method of manufacturing an ink jet head according to claim 1, wherein the thermosetting composition is a fluorine-based rubber composition exhibiting thermosetting.   19. The method of manufacturing an ink jet head according to claim 18, wherein the fluorine-based rubber composition exhibiting thermosetting contains a polymer having a fluorinated polyether skeleton in the main chain as a main component. The fluorinated polyether skeleton includes perfluoropolyether repeating units (—C _a F _{2 × a} O— [a is an integer in the range of 1 to 6]] in the range of 20 to 600. 20. The method of manufacturing an ink jet head according to claim 19, wherein the perfluoropolyether skeleton is repeatedly contained.   21. The method of manufacturing an ink jet head according to claim 1, wherein the thermosetting composition has a curing start temperature in a range of 40 ° C. or higher and 120 ° C. or lower.   The said thermosetting composition contains the fine powder silica surface-treated with the surface treating agent in the range of 1 to 30 parts by weight, The inkjet head according to any one of claims 1 to 21 Production method.   The method of manufacturing an ink jet head according to claim 22, wherein the surface treatment agent is a silane-based surface treatment agent.

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