JP2014111346A - Ink jet print head and ink jet print head manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ink jet print head and an ink jet print head manufacturing method.SOLUTION: The ink jet print head may comprise a vibrating substrate, an actuator formed on the vibrating substrate, and a reinforcement member formed around the circumference of the actuator.

Description

  The present invention relates to an inkjet print head and an inkjet print head manufacturing method, and more particularly to an inkjet print head and an inkjet print head manufacturing method that can reduce a phenomenon that a diaphragm is damaged by an external impact.

  Inkjet printheads are widely used for office and industrial purposes. In addition, as the range of use of the ink jet print head is further expanded, the performance of the ink jet print head is also being improved.

  As an example, the number of nozzles per unit length of the inkjet print head is gradually increased from 512 to 1024. However, such a high-density ink jet print head may cause the following problems.

  First, print quality may be degraded by overheating of the inkjet printhead.

  1024 heads (inkjet printheads with 1024 nozzles per unit length) have actuators arranged more densely than 512 heads (inkjet printheads with 512 nozzles per unit length). Therefore, it is easy to overheat in the ink discharge operation state. However, the heat generated from the ink jet print head can change the viscosity of the ink and reduce the print quality of the ink.

  Secondly, the vibration substrate is easily damaged.

  Since 1024 heads have more actuators than 512 heads in the same unit length, the amount of pressure applied per unit area of the vibration substrate is also large. However, the thickness of the vibration substrate is optimized according to the operating frequency of the actuator, and it is difficult to increase the thickness of the vibration substrate in proportion to the increased pressure. Therefore, in the 1024 head, when an external impact is applied during the operation of the actuator, or when a large number of actuators are operated for a long time, a phenomenon that the vibration substrate is damaged easily occurs.

  Third, current consumption is large.

  Since a large number of actuators are arranged in the same unit length in the 1024 head, the amount of current consumption required for the operation of the actuator is large. Accordingly, there is a disadvantage in that the operation efficiency of a high-density inkjet print head such as 1024 heads is lower than that of other inkjet print heads.

  Accordingly, there is an urgent need to develop a new type of inkjet print head to solve the above-described problems.

  On the other hand, Patent Document 1 and Patent Document 2 are given as prior art relating to an ink jet print head. However, these Patent Documents 1 and 2 do not specifically present any configuration for solving the above-described problems.

KR2007-083030 A JP 2006-315323 A

  SUMMARY An advantage of some aspects of the invention is to provide an ink jet print head that can reduce the thickness of the ink jet print head and a method of manufacturing the ink jet print head.

  Another object of the present invention is to provide an ink jet print head and a method of manufacturing the ink jet print head that can reduce the phenomenon that the diaphragm is damaged due to external impact and actuator operation.

  To achieve the above object, an inkjet printhead according to an embodiment of the present invention may include a vibration substrate, an actuator formed on the vibration substrate, and a reinforcing member formed on the periphery of the actuator.

  In the ink jet print head according to an embodiment of the present invention, the reinforcing member may be made of a dry film resist.

  In the inkjet print head according to an embodiment of the present invention, the reinforcing member may be formed at the same height as the actuator.

  In the inkjet print head according to an embodiment of the present invention, the reinforcing member may be formed at a height different from the thickness of the actuator.

  In the inkjet print head according to an embodiment of the present invention, the reinforcing member may be formed higher than the thickness of the actuator.

  In the ink jet print head according to the embodiment of the present invention, the thickness of the vibration substrate may be 2 μm or less.

  In the ink jet print head according to an embodiment of the present invention, the reinforcing member may be formed over the entire area of the vibration substrate other than the portion where the actuator is formed.

  To achieve the above object, an inkjet print head according to another embodiment of the present invention includes a flow path forming substrate on which a pressure chamber and an ink inlet are formed, and is coupled to the flow path forming substrate and connected to the ink inlet. A vibration substrate on which the through hole is formed, an actuator formed on the vibration substrate, a first reinforcing member formed on the periphery of the actuator, and a second reinforcing member formed on the periphery of the through hole , Can be included.

  In the inkjet print head according to another embodiment of the present invention, the first and second reinforcing members may be made of a dry film resist.

  In the inkjet print head according to another embodiment of the present invention, the first reinforcing member may be formed at the same height as the thickness of the actuator.

  In the inkjet print head according to another embodiment of the present invention, the first reinforcing member may be formed at a height different from the thickness of the actuator.

  In the inkjet print head according to another embodiment of the present invention, the first reinforcing member may be formed higher than the thickness of the actuator.

  In the inkjet print head according to another embodiment of the present invention, the thickness of the vibration substrate may be 2 μm or less.

  In the inkjet print head according to another embodiment of the present invention, the first and second reinforcing members may be formed over the entire area of the vibration substrate other than the portion where the actuator and the through hole are formed.

  In order to achieve the above object, a method of manufacturing an inkjet print head according to an embodiment of the present invention includes a step of forming a vibration substrate on a flow path forming substrate, a step of forming an actuator on the vibration substrate, and reinforcing the periphery of the actuator. Forming a member.

  In the method of manufacturing an ink jet print head according to an embodiment of the present invention, the actuator may be formed by thin film deposition or a sol-gel process.

  In the method of manufacturing an ink jet print head according to an embodiment of the present invention, the thickness of the vibration substrate may be 2 μm or less.

  The present invention makes it possible to reduce the thickness of an ink jet print head.

  In addition, the present invention can reduce the damage phenomenon of the vibration substrate due to external impact and long-time operation of the actuator.

1 is a perspective view of an inkjet print head according to an embodiment of the present invention. FIG. 2 is a cross-sectional view of the inkjet print head shown in FIG. 1 taken along the line AA. FIG. 2 is a cross-sectional view taken along the line BB of the ink jet print head illustrated in FIG. 1. FIG. 6 is a cross-sectional view taken along the line BB for explaining another form of the ink jet print head shown in FIG. 1. FIG. 6 is a cross-sectional view taken along the line BB for explaining another form of the ink jet print head shown in FIG. 1. FIG. 6 is a perspective view of an inkjet print head according to another embodiment of the present invention. FIG. 7 is a CC cross-sectional view of the ink jet print head illustrated in FIG. 6. FIG. 6 is a perspective view of an inkjet print head according to still another embodiment of the present invention. It is a work process figure for demonstrating the manufacturing method of the inkjet print head by one Example of this invention.

  It is an object of the present invention to reduce the size and thickness of an inkjet print head.

  For this reason, according to the present invention, the thickness of the actuator can be made thinner than before. In this case, the amount of current consumption required for driving the actuator can be greatly reduced, and the thickness of the vibration substrate can be reduced.

  Meanwhile, the present invention may further include a reinforcing member. The reinforcing member is formed on the vibration substrate, and the phenomenon that the vibration substrate is damaged by an external impact can be reduced.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

  In the following description of the present invention, the terms indicating the components of the present invention are named in consideration of the functions of the respective components, and are understood to limit the technical components of the present invention. must not.

  FIG. 1 is a perspective view of an ink jet print head according to an embodiment of the present invention, FIG. 2 is a cross-sectional view of the ink jet print head taken along line AA in FIG. 1, and FIG. FIG. 4 is a cross-sectional view taken along the line BB of the print head. FIGS. 4 and 5 are cross-sectional views taken along the line BB for explaining another embodiment of the inkjet print head shown in FIG. 1, and FIG. FIG. 7 is a cross-sectional view of the inkjet print head shown in FIG. 6, and FIG. 8 is a cross-sectional view of the inkjet print head according to another embodiment of the present invention. FIG. 9 is a work process diagram for explaining a method of manufacturing an ink jet print head according to an embodiment of the present invention.

  An ink jet print head according to an embodiment of the present invention will be described with reference to FIGS.

  The inkjet print head 100 can include a nozzle forming substrate 110, a flow path forming substrate 120, a vibration substrate 130, an actuator 140, and a reinforcing member 150. Here, the nozzle formation substrate 110, the flow path formation substrate 120, and the vibration substrate 130 can be sequentially stacked along the vertical direction (reference direction in FIG. 1).

  The nozzle forming substrate 110 may be a single crystal silicon substrate. However, the nozzle forming substrate 110 may be formed of an SOI (Silicon on Insulator) substrate as necessary. In this case, the nozzle forming substrate 110 may be a stacked structure in which a silicon substrate and a large number of insulating members are stacked.

  A number of nozzles 210 may be formed on the nozzle forming substrate 110. More specifically, the nozzle 210 can completely penetrate the nozzle forming substrate 110 in the vertical direction. That is, the depth of the nozzle 210 may be the same as or smaller than the thickness of the nozzle forming substrate 110. When the nozzle depth is smaller than the nozzle forming substrate 110, another flow path larger than the nozzle diameter and smaller than the pressure chamber width is formed to prevent a rapid pressure drop from the chamber toward the nozzle during ink ejection. be able to. The size of the cross section of the nozzle 210 may be the same along the thickness direction of the nozzle forming substrate 110 as shown in FIG. However, the cross-sectional size of the nozzle 210 is not limited to such a shape. For example, the size of the cross section of the nozzle 210 may be different along the thickness direction of the nozzle forming substrate 110. That is, the size of the cross section of the nozzle 210 can be gradually reduced from the upper surface to the lower surface of the nozzle forming substrate 110. The nozzles 210 thus formed can be formed at intervals along one direction of the nozzle forming substrate 110 (X-axis direction with reference to FIG. 1).

  A restrictor 230 may be further formed on the nozzle forming substrate 110. The restrictor 230 is formed to a predetermined depth, and can connect the pressure chamber 220 and the manifold 240 as shown in FIG. On the other hand, in this embodiment, it is described that the restrictor 230 is formed on the nozzle forming substrate 110, but the restrictor 230 can be formed on the flow path forming substrate 120 as necessary.

  The flow path forming substrate 120 can be made of a single crystal silicon substrate, like the nozzle forming substrate 110. However, the flow path forming substrate 120 can be made of an SOI (Silicon on Insulator) substrate as required. In this case, the flow path forming substrate 120 may be a laminated structure in which a silicon substrate and a large number of insulating members are laminated. The flow path forming substrate 120 configured as described above can be formed on one surface (upper surface) of the nozzle forming substrate 110.

  A pressure chamber 220 and a manifold 240 may be formed on the flow path forming substrate 120.

  The pressure chamber 220 may have a predetermined volume. More specifically, the pressure chamber 220 may have a volume that is equal to or greater than the volume of ink that can be ejected by a single actuation of the actuator 140. Here, the former can be advantageous for quantitative ink ejection, and the latter can be advantageous for continuous ejection of the inkjet print head 100.

  The manifold 240 is formed at a predetermined distance from the pressure chamber 220 and can be connected to the pressure chamber 220 by a restrictor 230. The manifold 240 can be formed long along the length direction of the flow path forming substrate 120 (X-axis direction with reference to FIG. 1). That is, the manifold 240 is integrally formed along the length direction of the flow path forming substrate 120 and can be connected simultaneously with the multiple pressure chambers 220. The manifold 240 is not shown in the drawing, but can be connected to an ink supply tank. Accordingly, the ink in the ink supply tank can be supplied to each pressure chamber 220 via the manifold 240.

  Meanwhile, the pressure chamber 220 and the manifold 240 can be formed to the same depth as the flow path forming substrate 120. In this case, the pressure chamber 220 and the manifold 240 can be easily formed by an etching process.

  The vibration substrate 130 can be formed on the flow path forming substrate 120. More specifically, the vibration substrate 130 can be formed on one surface (upper surface) of the flow path forming substrate 120. The vibration substrate 130 may include a vibration layer 132 and an antioxidant layer 134. The vibration layer 132 can be made of single crystal silicon. The anti-oxidation layer 134 can prevent the ceramic material of the piezoelectric element formed on the upper surface of the anti-oxidation layer 134 from diffusing into the vibration layer 132. The vibration substrate 130 configured as described above can transmit the driving force generated by the actuator 140 to the pressure chamber 220.

  On the other hand, the thickness (or height) of the vibration substrate 130 may be 2 μm or less. Thus, when the thickness of the vibration substrate 130 is changed to 2 μm or less, the driving force of the actuator 140 can be effectively transmitted to the pressure chamber 220 even if the height of the actuator 140 is reduced. Therefore, the overall height of the ink jet print head 100 can be greatly reduced, whereby the ink jet print head 100 can be reduced in size and thickness.

  The actuator 140 may be formed on the vibration substrate 130. The actuator 140 may have a size corresponding to the length L2 and the width W2 of the pressure chamber 220. In detail, the length L1 of the actuator 140 may be the same as the length L2 of the pressure chamber 220 as illustrated in FIG. 2, and the width W1 of the actuator 140 is illustrated in FIG. Thus, the width W2 of the pressure chamber 220 may be the same. However, the length L1 and width W1 of the actuator 140 can be made larger than the length L2 and width W2 of the pressure chamber 220 for easy connection between the actuator 140 and the electrode.

  The actuator 140 can include a lower electrode 142, a piezoelectric element 144, and an upper electrode 146. The lower electrode 142 may be formed on the vibration substrate 130. In detail, the lower electrode 142 may be formed on the entire upper surface of the antioxidant layer 134. The piezoelectric element 144 may be formed on the lower electrode 142. In detail, the piezoelectric element 144 may be formed in a portion corresponding to the pressure chamber 220. Here, the length L1 and the width W1 of the piezoelectric element 144 may be the same as the length L2 and the width W2 of the pressure chamber 220. The upper electrode 146 may be formed on the piezoelectric element 144. Here, the size of the upper electrode 146 may be the same as the size of the piezoelectric element 144. However, the upper electrode 146 can be formed smaller than the piezoelectric element 144 in order to prevent a short circuit between the upper electrode 146 and the lower electrode 142.

  The actuator 140 configured as described above can generate a driving force by deforming the piezoelectric element 144 by a current signal supplied through the lower electrode 142 and the upper electrode 146.

  On the other hand, the size (height, length, width) of the actuator 140 referred to in the present specification and claims refers to a portion other than the lower electrode 142.

  The reinforcing member 150 can be formed on the vibration substrate 130. In detail, the reinforcing member 150 may be formed on the lower electrode 142 and may have the same height as the actuator 140. That is, the height h2 of the reinforcing member 150 may be the same as the height h1 of the actuator 140.

  The reinforcing member 150 can be limited to the periphery of the actuator 140. However, if necessary, the reinforcing member 150 can be formed in all regions of the vibration substrate 130 other than the portion where the actuator 140 is formed.

  The reinforcing member 150 may be made of a negative photoresist, a positive photoresist, or a dry film resist. However, the material of the reinforcing member 150 is not limited to the dry film resist, and may be changed to any material as long as the material can reinforce the strength of the vibration substrate 130.

  The reinforcing member 150 formed in this way can improve the strength of the vibration substrate 130. In particular, in the present embodiment, the reinforcing member 150 is formed on the periphery of the actuator 140, so that the impact transmitted from the actuator 140 can be effectively dispersed, and the driving force of the actuator 140 is adjacent to the pressure chamber 220. Can be blocked from being transmitted to.

  Therefore, according to the present embodiment, the ink discharge quality and performance of the ink jet print head can be improved.

  Meanwhile, the reinforcing member 150 may be formed lower than the height h1 of the actuator 140 or higher than the height h1 of the actuator 140, as shown in FIGS. Here, the former can improve the vibration efficiency of the vibration substrate 130, and the latter has an advantage that an external impact can be effectively blocked from being transmitted to the vibration substrate 130 or the actuator 140. Further, the latter can prevent the wire bonding apparatus from damaging the actuator due to malfunction or the occurrence of a short circuit due to incorrect connection of the wires in the electrical connection process of the actuator by wire bonding.

  Next, an inkjet print head according to another embodiment of the present invention will be described with reference to FIGS. For reference, the same components in the present embodiment as those in the embodiment described above are denoted by the same reference numerals, and detailed description thereof will be omitted.

  The inkjet print head 100 according to the present embodiment may further include a second reinforcing member 160. More specifically, the first reinforcing member 150 may be formed on the periphery of the actuator 140, and the second reinforcing member 160 may be formed on the periphery of the ink inlet 250. Here, as described above, in the first reinforcing member 150, the vibration substrate 130 is damaged by driving the actuator 140, or the vibration substrate 130 around the actuator 140 is damaged by an external impact during a subsequent process such as packaging. That can be reduced. Similarly, the second reinforcing member 160 can increase the strength of the ink inlet 250 and reduce the damage of the vibration substrate 130 of the ink inlet 250 due to an external impact. Here, a through hole 260 having a shape corresponding to the ink inlet 250 may be formed in the second reinforcing member 160.

  In the inkjet print head 100 according to the present embodiment, the flow path forming substrate 120 may be composed of a plurality of substrates. More specifically, the flow path forming substrate 120 may include a first flow path forming substrate 122 and a second flow path forming substrate 124. Here, a damper 212 and a restrictor 230 may be formed on the first flow path forming substrate 122, and a pressure chamber 220 and a manifold 240 may be formed on the second flow path forming substrate 124. Meanwhile, the manifold 240 may be connected to an ink supply tank through an ink inlet 250 that penetrates the vibration substrate 130.

  In the inkjet print head 100 configured as described above, the strength around the ink inlet 250 is reinforced by the second reinforcing member 160, so that the ink inlet 250 can be attached to or detached from the ink inlet 250. The phenomenon that the shape of 250 is damaged or broken can be reduced.

  Further, in the inkjet print head 100 of the present invention, the flow path forming substrate 120 is divided into a plurality of substrates, and the damper 212 and the restrictor 230 can be easily formed by wet etching.

  On the other hand, in this embodiment, the reinforcing members are classified into the first reinforcing member 150 and the second reinforcing member 160. However, as shown in FIG. It can be formed integrally. Further, the reinforcing member 150 can be formed on the entire upper surface of the vibration substrate 130.

  Next, a method for manufacturing an ink jet print head according to an embodiment of the present invention will be described with reference to FIG.

  The method of manufacturing an inkjet print head according to an embodiment of the present invention may include a step of forming the vibration substrate 130, a step of forming the actuator 140, and a step of forming the reinforcing member 150.

1) Formation Step of the Vibration Substrate 130 This step can be a step of forming the vibration substrate 130. More specifically, this step may be a step of forming the vibration substrate 130 on the upper part of the flow path forming substrate 120. This step can include all of the step of forming the vibration layer 132 and the step of forming the antioxidant layer 134. In other words, this stage can be composed of two processes in which the vibration layer 132 is formed on the upper part of the flow path forming substrate 120 and the antioxidant layer 134 is formed on the vibration layer 132. For reference, the thickness of the vibration substrate 130 formed at this stage may be 2 μm or less.

2) Formation Step of Actuator 140 This step can be a step of forming the actuator 140. More specifically, this step may be a step of forming the actuator 140 on the vibration substrate 130. This step may include all of the step of forming the lower electrode 142, the step of forming the piezoelectric element 144, and the step of forming the upper electrode 146. Here, the piezoelectric element 144 may be formed by thin film deposition or sol-gel process. When the piezoelectric element 144 is formed by such a method, the thickness (2 μm or less) of the piezoelectric element 144 can be significantly reduced. However, the method for forming the piezoelectric element 144 is not limited to the two methods described above, and the piezoelectric element 144 can be formed by other methods.

3) Formation Step of Reinforcing Member 150 This step can be a step of forming the reinforcing member 150 on the vibration substrate 130. In detail, this step may be a step of forming the reinforcing member 150 on the periphery of the actuator 140. The reinforcing member 150 can be a dry film resist. For example, the reinforcing member 150 may be made of a mask layer (usually a photoresist) used in the process of forming the piezoelectric element 144 or the upper electrode 146 on the vibration substrate 130, or may be made of a part of the mask layer. However, the reinforcing member 150 is not composed of only the mask layer, and the reinforcing member 150 can be formed on the vibration substrate 130 by another process as necessary.

  The reinforcing member 150 may be formed to have the same thickness as the actuator 140 or a thickness different from that of the actuator 140. Here, the thickness of the reinforcing member 150 may vary depending on the method of forming the reinforcing member 150 or the type of the inkjet print head 100 to be manufactured.

  The present invention is not limited only to the embodiments described above, and any person having ordinary knowledge in the technical field to which the present invention pertains will have the technical idea of the present invention described in the following claims. Various changes can be made without departing from the gist.

DESCRIPTION OF SYMBOLS 100 Inkjet print head 110 Nozzle formation board 120 Flow path formation board 130 Vibration board 140 Actuator 150, 160 Reinforcement member 210 Nozzle 220 Pressure chamber 230 Restrictor 240 Manifold 250 Ink inlet 260 Through-hole

Claims (17)

A vibration substrate;
An actuator formed on the vibration substrate;
An ink jet print head comprising: a reinforcing member formed on a peripheral edge of the actuator.   The inkjet print head of claim 1, wherein the reinforcing member is made of a negative photoresist, a positive photoresist, or a dry film resist.   The ink jet print head according to claim 1, wherein the reinforcing member is formed at a height equal to a thickness of the actuator.   The inkjet print head according to claim 1, wherein the reinforcing member is formed at a height different from a thickness of the actuator.   The ink jet print head according to claim 4, wherein the reinforcing member is formed higher than a thickness of the actuator.   The ink jet print head according to claim 1, wherein the vibration substrate has a thickness of 2 μm or less.   The ink jet print head according to claim 1, wherein the reinforcing member is formed over the entire area of the vibration substrate other than a portion where the actuator is formed. A flow path forming substrate on which a pressure chamber and an ink inlet are formed;
A vibration substrate coupled to the flow path forming substrate and having a through hole connected to the ink inlet;
An actuator formed on the vibration substrate;
A first reinforcing member formed on the periphery of the actuator;
An ink jet print head comprising: a second reinforcing member formed at a peripheral edge of the through hole.   The inkjet print head of claim 8, wherein the first reinforcing member and the second reinforcing member are made of a negative photoresist, a positive photoresist, or a dry film resist.   The ink jet print head according to claim 8, wherein the first reinforcing member is formed at a height equal to a thickness of the actuator.   The ink jet print head according to claim 8 or 9, wherein the first reinforcing member is formed at a height different from a thickness of the actuator.   The ink jet print head according to claim 11, wherein the first reinforcing member is formed higher than a thickness of the actuator.   The inkjet print head according to any one of claims 8 to 12, wherein a thickness of the vibration substrate is 2 µm or less.   14. The inkjet print according to claim 8, wherein the first reinforcing member and the second reinforcing member are formed over the entire area of the vibration substrate other than a portion where the actuator and the through hole are formed. head. Forming a vibration substrate on the flow path forming substrate;
Forming an actuator on the vibration substrate; and
Forming a reinforcing member on a peripheral edge of the actuator.   The method of manufacturing an ink jet print head according to claim 15, wherein the actuator is formed by thin film deposition or a sol-gel process.   The method of manufacturing an ink jet print head according to claim 15 or 16, wherein the vibration substrate has a thickness of 2 m or less.

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