Patent Application
20190389217
The present application is based on, and claims priority from, JP Application Serial Number 2018-117507, filed Jun. 21, 2018, the disclosure of which is hereby incorporated by reference herein in its entirety.
The present disclosure relates to a liquid ejecting head and a liquid ejecting apparatus.
For example, the liquid ejecting head described in JP-A-2015-30153 has a structure in which a nozzle plate having a nozzle, a flow path substrate having a nozzle communication flow path coupled to the nozzle of the nozzle plate, and a pressure chamber substrate having a pressure chamber coupled to the nozzle communication flow path of the flow path substrate are laminated in order. The flow path substrate has a common liquid chamber for supplying a liquid to a plurality of pressure chambers and a supply flow path via which the common liquid chamber communicates with each pressure chamber. The liquid ejecting head ejects a liquid droplet from the nozzle by causing a pressure change in the liquid in the pressure chamber. The liquid is supplied to each pressure chamber from the common liquid chamber via the supply flow path.
When a plurality of supply flow paths are formed in the flow path substrate by etching, a wall surface of a portion from the common liquid chamber toward each supply flow path may have a “sagging shape” in which the wall surface is lowered to the supply flow path side. The term “sagging” means drooping, for example, a tip end is lowered. The sagging shape of an inlet portion of the supply flow path is a shape in which the wall surface of the inlet portion of the supply flow path is expanded.
When the inlet portion of the supply flow path has the sagging shape, a bubble adhering to the wall surface of the inlet portion of the supply flow path may be difficult to be discharged at the time of cleaning. The bubble remaining in the supply flow path affects the ejection of the liquid droplet, so that it is necessary to suppress the residual bubbles in the supply flow path.
According to an aspect of the present disclosure, there is provided a liquid ejecting head including a nozzle plate that includes a nozzle, a multilayer substrate that includes a first flow path arrangement layer and a second flow path arrangement layer in an order of arrangement from a side of the nozzle plate, and includes a nozzle communication flow path and a common liquid chamber, and a pressure chamber substrate that includes a first pressure chamber communicating with the nozzle via the nozzle communication flow path and a second pressure chamber disposed next to the first pressure chamber via a partition wall, in which the common liquid chamber communicates with the first pressure chamber and the second pressure chamber, the multilayer substrate includes a liquid chamber wall portion disposed on a side of the second flow path arrangement layer from the common liquid chamber, the liquid chamber wall portion includes a first wall surface facing the common liquid chamber, the multilayer substrate includes a supply flow path via which the common liquid chamber communicates with the first pressure chamber and has an inlet portion coupled to the first wall surface, when a direction from the common liquid chamber toward the first pressure chamber is defined as a first direction and a direction intersecting the first direction is defined as a second direction, the supply flow path includes a first portion having a first width in the inlet portion and a second portion having a second width in a first cross section along the first direction and the second direction, and the first width is narrower than the second width.
In addition, a liquid ejecting apparatus of the present disclosure has an aspect that includes the liquid ejecting head.
Hereinafter, embodiments of the present disclosure will be described. As a matter of course, the following embodiments merely exemplify the present disclosure, and not all of the features described in the embodiments are necessarily essential to the solution means of the disclosure.
First, an outline of the technology included in the present disclosure will be described with reference to the examples illustrated in
In addition, in the present application, the numerical range “Min to Max” means the minimum value Min or more and the maximum value Max or less. The compositional ratio represented by the chemical formula represents the stoichiometric ratio, and substances represented by the chemical formula include those deviating from the stoichiometric ratio.
Aspect 1
A liquid ejecting head 1 according to an aspect of the present technology includes a nozzle plate 80, a multilayer substrate 30, and a pressure chamber substrate 10. The nozzle plate 80 has a nozzle 81. The multilayer substrate 30 includes a first flow path arrangement layer 131 and a second flow path arrangement layer 132 in an order of arrangement from a side of the nozzle plate 80. The multilayer substrate 30 has a nozzle communication flow path and a common liquid chamber 40. The pressure chamber substrate 10 has a first pressure chamber 121 communicating with the nozzle 81 via the nozzle communication flow path 31 and a second pressure chamber 122 disposed next to the first pressure chamber 121 via a partition wall 12a. The common liquid chamber 40 communicates with the first pressure chamber 121 and the second pressure chamber 122.
The multilayer substrate 30 includes a liquid chamber wall portion 33 disposed on a side of the second flow path arrangement layer 132 from the common liquid chamber 40. The liquid chamber wall portion 33 has a first wall surface 33a facing the common liquid chamber 40. The multilayer substrate 30 has a supply flow path 32 via which the common liquid chamber 40 communicates with the first pressure chamber 121 and has an inlet portion coupled to the first wall surface 33a.
Here, a direction from the common liquid chamber 40 toward the first pressure chamber 121 is defined as a first direction D1, and a direction intersecting the first direction D1 is defined as a second direction D2. As exemplified in
In the above aspect 1, since the width of the supply flow path 32 is narrower than the second portion 320 at the inlet portion from the common liquid chamber 40 in the first cross section SC1, a bubble adhering to the wall surface of the inlet portion of the supply flow path 32 are likely to be discharged at the time of cleaning. Therefore, according to this aspect, it is possible to provide the liquid ejecting head that improves a discharge performance of the bubbles of the supply flow path.
Here, the nozzle is a small hole which a liquid droplet such as an ink droplet ejects.
The pressure chamber is a space for applying pressure to the liquid in the inside.
The liquid ejecting head is also called a liquid discharge head.
The above-described appendix also applies to the following aspects.
The multilayer substrate 30 may include an insulating layer 141 having a material different from a material forming the first flow path arrangement layer 131 and a material forming the second flow path arrangement layer 132 between the first flow path arrangement layer 131 and the second flow path arrangement layer 132. As exemplified in
Here, as the material forming the first flow path arrangement layer and the second flow path arrangement layer, a semiconductor such as silicon, metal, ceramics, or the like can be used. As the material forming the insulating layer, a material different from the materials forming the first flow path arrangement layer and the second flow path arrangement layer can be used from among silicon oxide, metal oxide, ceramics, synthetic resin, and the like. For example, when an SOI substrate is used for the multilayer substrate, an insulating layer can be formed from the silicon oxide layer and the first flow path arrangement layer and the second flow path arrangement layer can be formed from the silicon layers on both sides of the above-described silicon oxide layer. SOI is an abbreviation for “silicon on insulator”.
The insulating layer of the multilayer substrate is not limited to one layer and may be two or more layers.
The above-described appendix also applies to the following aspects.
In addition, the first portion 310 may include a second facing portion 312 protruding inside the supply flow path 32 from the liquid chamber wall portion 33 at a position facing the first facing portion 311. According to this aspect, it is possible to provide a technology for further improving the discharge performance of the bubbles of the supply flow path.
Furthermore, the supply flow path 32 may include a second inclined portion 350 having a third wall surface 351 inclined with respect to the first direction D1 between the second facing portion 312 and the second portion 320. According to this aspect, since the second inclined portion 350 is provided between the second facing portion 312 and the second portion 320 in the supply flow path 32, the flow of the liquid Q1 improves and the residual bubbles in the supply flow path 32 are further suppressed. Therefore, according to this aspect, it is possible to provide a technology for further improving the discharge performance of the bubbles of the supply flow path.
The fact that the wall surfaces of the first inclined portion 340 and the second inclined portion 350 are inclined with respect to the first direction D1 means that the wall surfaces of the first inclined portion 340 and the second inclined portion 350 are not along the first direction D1 and the wall surfaces of the first inclined portion 340 and the second inclined portion 350 are not orthogonal to the first direction D1.
The inclined wall surface of the supply flow path may be located between the first portion 310 and the second portion 320 in the first cross section SC1. Therefore, in a cross section along the first direction D1 and not along the second direction D2, the inclined wall surface may not be present in the supply flow path 32, or the inclined wall surface may be present in the supply flow path 32.
The above-described appendix also applies to the following aspects.
As exemplified in
In the above aspect, since the first inclined portion 340 is located at a position corresponding to the first angle AN1 when the supply flow path 32 is viewed from the first direction D1, the residual bubbles of the supply flow path 32 are further suppressed. Therefore, according to this aspect, it is possible to provide a technology for further improving the discharge performance of the bubbles of the supply flow path.
In addition, as exemplified in
In the above aspect, since the first inclined portion 340 is located at a position corresponding to the first angle AN1 and the second inclined portion 350 is located at a position corresponding to the second angle AN2 when the supply flow path 32 is viewed from the first direction D1, the residual bubbles of the supply flow path are further suppressed. Therefore, according to this aspect, it is possible to provide a technology for further improving the discharge performance of the bubbles of the supply flow path.
Furthermore, the first angle AN1 and the second angle AN2 may be acute angles. In the above aspect, since the first inclined portion 340 is located at a position corresponding to the first angle AN1 when the supply flow path 32 is viewed from the first direction D1, the residual bubbles of the supply flow path 32 are further suppressed. Therefore, according to this aspect, it is possible to provide a technology for further improving the discharge performance of the bubbles of the supply flow path.
The above-described first inclined portion 340 may be separated from a coupling portion J1 between the supply flow path 32 and the first pressure chamber 121. The aspect can further increase the rigidity of the wall of the supply flow path.
As exemplified in
The first flow path arrangement layer 131 and the second flow path arrangement layer 132 may be made of silicon. A plane index of a front surface of the multilayer substrate 30 may be (110). A plane index of a wall surface of the first inclined portion 340 may be (111). According to this aspect, it is possible to provide the liquid ejecting head suitable for improving the discharge performance of the bubbles of the supply flow path.
Here, the plane index is also called Miller index. A surface whose plane index is (110) is also called a (110) plane. A surface whose plane index is (111) is also called a (111) plane.
As exemplified in
As exemplified in
As exemplified in
Here, the liquid ejecting apparatus is also referred to as a liquid discharge apparatus.
Furthermore, the present technology also has aspects such as a manufacturing method of the multilayer substrate, a manufacturing method of the liquid ejecting head, a manufacturing method of the liquid ejecting apparatus, and the like.
The X direction, the Y direction, and the Z direction are orthogonal to each other, and these directions are also included in the present technology as long as these directions intersect with each other even when these directions are not orthogonal due to design or the like. The fact of “orthogonal” is not limited to strict 90°, and includes deviation from strict 90° due to error. In addition, the same in direction, position, and the like are not limited to strict matching, and includes deviation from strict matching due to error. Furthermore, the description of the positional relationship of each part is merely an example. Therefore, it is also included in the present technology to change a left-right direction to a vertical direction or a front-rear direction, to change the vertical direction to the left-right direction or the front-rear direction, to change the front-rear direction to the left-right direction or the vertical direction, and the like.
The liquid ejecting head 1 illustrated in
The pressure chamber substrate 10 has the pressure chamber 12 corresponding to each nozzle 81, an actuator 2 on a protective substrate side surface 10a, and an opening of the pressure chamber 12 on a multilayer substrate side surface 10b. The pressure chamber substrate 10 has two rows of pressure chambers in which multiple pressure chambers 12 are arranged in the Y direction which is the arrangement direction of the nozzles 81. That is, in the pressure chamber substrate 10, two pressure chambers 12 are disposed in the X direction which is the longitudinal direction of the pressure chamber 12. As matter of course, in addition to having two rows of pressure chambers, the pressure chamber substrate may have one row of pressure chamber or three or more rows of pressure chambers. The multilayer substrate side surface 10b is bonded to a pressure chamber substrate side surface 30a of the multilayer substrate 30. The pressure chamber substrate 10 and the multilayer substrate 30 are bonded to each other by an adhesive, for example. In the present specification, the bonding and contacting includes both presence of intervening material such as an adhesive therebetween, and absence of intervening material therebetween.
For example, the pressure chamber 12 is formed in a substantially quadrangular shape elongated in a plan view as viewed from the protective substrate side surface 10a with respect to the pressure chamber substrate 10, and is disposed in the Y direction via the partition wall 12a as illustrated in
As the material forming the pressure chamber substrate 10 except for the actuator 2, a silicon substrate, a metal such as SUS, ceramics, glass, a synthetic resin, or the like can be used. Here, SUS is an abbreviation of stainless steel. Although not particularly limited, the pressure chamber substrate 10 can be formed of a silicon monocrystalline substrate having a relatively large film thickness of, for example, approximately several hundred μm and high rigidity. The pressure chambers 12 partitioned by the plurality of partition walls 12a can be formed by anisotropic wet etching, using an alkaline solution such as KOH aqueous solution, for example.
The actuator 2 illustrated in
As the material forming the vibration plate 16, a silicon oxide represented by SiOx, a metal oxide, ceramics, a synthetic resin, or the like can be used. The vibration plate may be integrally formed with the pressure chamber substrate by modifying the front surface of the pressure chamber substrate or may be bonded to the pressure chamber substrate and laminated. Although not particularly limited, the vibration plate can be formed on the pressure chamber substrate by thermally oxidizing the silicon wafer for the pressure chamber substrate with a diffusion furnace at approximately 1000° C. to 1200° C. In addition, the vibration plate may have a laminated structure such as a structure in which a zirconium oxide layer is laminated on a silicon oxide layer.
The piezoelectric element 3 illustrated in
The electrodes 21 and 22 and the lead electrode can be formed by, for example, forming and patterning an electrode film on a vibration plate by a vapor phase method such as a sputtering method. The piezoelectric layer 23 can be formed by, for example, baking and patterning a piezoelectric precursor film formed on the first electrode by a liquid phase method such as a spin coating method or a gas phase method.
A driving element for moving the liquid from the pressure chamber to the nozzle is not limited to the above-described piezoelectric element 3, and a heating element or the like for generating a bubble in the pressure chamber by heat generation may be used. Therefore, the actuator 2 is not limited to the piezoelectric actuator including the piezoelectric element and the vibration plate, and may be an actuator including a heating element that transmits heat to the pressure chamber.
The multilayer substrate 30 illustrated in
As illustrated in
The common liquid chamber 40 stores liquid Q1 such as ink. The inflow flow path 38 has a hole shape penetrating in the Z direction with respect to the second flow path arrangement layer 132 and allows the liquid Q1 to pass from the second common liquid chamber 72 of the case head 70 to the common liquid chamber 40. An inlet port 42, which is an outlet portion of the inflow flow path 38, is an opening portion of the inflow flow path 38 formed in the common liquid chamber 40. The position of the inflow port is aligned with the surface of the second flow path arrangement layer 132 on the side of the insulating layer 141. The supply flow path 32 has a hole shape penetrating in the Z direction with respect to the second flow path arrangement layer 132, and is an individual flow path arranged for each pressure chamber 12. Therefore, the liquid flow path branches from the common liquid chamber 40 into a plurality of supply flow paths 32. Each supply flow path 32 passes the liquid Q1 from the common liquid chamber 40 to the corresponding pressure chamber 12. A supply port 44 which is an inlet portion of the supply flow path 32 is an opening portion of the supply flow path 32 formed in the common liquid chamber 40, and is coupled to the first wall surface 33a of the liquid chamber wall portion 33 and the insulating layer 141. The plurality of supply ports 44 in each common liquid chamber 40 are arranged in the Y direction which is the arrangement direction of the pressure chambers 12. The position of each supply ports 44 is aligned with the surface of the second flow path arrangement layer 132 on side of the insulating layer 141. The nozzle communication flow path 31 has a hole shape that penetrates the entire multilayer substrate 30 in the first direction D1 which is the Z direction, and is an individual flow path arranged for each pressure chamber 12. Therefore, the nozzle communication flow path 31 has a hole shape that penetrates the first flow path arrangement layer 131, the insulating layer 141, and the second flow path arrangement layer 132. Each nozzle communication flow path 31 passes the liquid Q1 from the pressure chamber 12 to the nozzle 81. The multilayer substrate 30 has two rows of nozzle communication flow paths 31 aligned with the pressure chamber rows. In each row of the nozzle communication flow path 31, as illustrated in
As will be described in detail later, projection portions 300 are arranged in the inlet portion coupled to the first wall surface 33a and the insulating layer 141 in the supply flow path 32. In this specific example, projection portions 300 are also arranged in the nozzle communication flow path 31.
As the materials forming the first flow path arrangement layer 131 and the second flow path arrangement layer 132, semiconductors such as silicon represented by Si, metals, ceramics, and the like can be used. As the material forming the insulating layer 141, silicon oxide, metal oxide, ceramics, synthetic resin, or the like can be used. Although not particularly limited, when an SOI substrate is used for the multilayer substrate 30, the first flow path arrangement layer 131 and the second flow path arrangement layer 132 are made of silicon and the insulating layer 141 is made of silicon oxide. As the SOI substrate, for example, it is possible to use a multilayer substrate in which the first flow path arrangement layer 131 and the second flow path arrangement layer 132 are silicon single crystal substrates and whose surface is the (110) plane.
The liquid flow path of the multilayer substrate 30 can be formed by, for example, anisotropic wet etching using an alkaline solution such as KOH aqueous solution or the like.
As illustrated in
When the actuator 2 is protected by the case head or the like, it is possible to omit the protective substrate 50 from the liquid ejecting head 1.
As illustrated in
A drive circuit 65 illustrated in
As illustrated in
As the material forming the nozzle plate 80, a metal such as stainless steel, a semiconductor such as glass, ceramics, synthetic resin, silicon, or the like can be used. Although not particularly limited, the nozzle plate 80 can be formed of glass ceramics having a thickness of, for example, approximately 0.01 to 1 mm.
The sealing plate 90 illustrated in
In the liquid ejecting head 1 having the above-described structure, the liquid Q1 sequentially passes through the liquid introduction portion 73, the second common liquid chamber 72, the inflow flow path 38, the common liquid chamber 40, the supply flow path 32, the pressure chamber 12, and the nozzle communication flow path 31, and is ejected as a droplet Q0 from the nozzle 81 by the operation of the actuator 2. Here, the liquid introduction portion 73, the second common liquid chamber 72, the inflow flow path 38, and the common liquid chamber 40 are common flow paths for the plurality of pressure chambers 12. The supply flow path 32, the pressure chamber 12, the nozzle communication flow path 31, and the nozzle 81 are individual flow paths corresponding to each pressure chambers 12. Therefore, the liquid Q1 in the common liquid chamber 40 is divided into individual supply flow paths 32 and flows out. When the drive circuit 65 applies a voltage between the first electrode 21 and the second electrode 22 to bend the actuator 2 toward the pressure chamber 12 side, the liquid Q1 in the pressure chamber 12 flows to the nozzle 81 via the nozzle communication flow path 31. As a result, the droplet Q0 is ejected from the nozzle 81. In addition, when the drive circuit 65 stops applying the above-described voltage, the actuator 2 moves to the side opposite to the pressure chamber 12, so that the liquid Q1 in the common liquid chamber 40 flows into the pressure chamber 12 via the supply flow path 32. Therefore, the actuator 2 can repeatedly eject the droplet Q0 from the nozzle 81.
When a plurality of droplets Q0 ejected by the liquid ejecting head 1 land on a print substrate, dots of the plurality of droplets Q0 are formed on the print substrate, and a printing image of a plurality of dots is expressed on the print substrate. Here, the print substrate is a material that holds a printed image, and has various two-dimensional shapes such as a polygon and a circle, and various three-dimensional shapes such as prismatic and spherical. As the material forming the print substrate, paper, synthetic resin, metal, ceramics, and the like can be used. Dots are the smallest unit of recording results formed by the liquid droplets on the print substrate. In order to increase the resolution of the printed image, it is necessary to make the nozzle pitch finer, for example, 300 dpi or more. In order to make the nozzle pitch finer, it is necessary to narrow the interval between the adjacent nozzles 81, and it is necessary to narrow the interval between the adjacent supply flow paths 32.
First, in a thermal oxidation step ST91, a treatment of thermally oxidizing the surface of the base substrate at 1000° C. to 1200° C. is performed. By this treatment, as illustrated in
Next, in a through-hole forming step ST92, a portion of the hard mask film 951 corresponding to a supply flow path corresponding region 932a and an inflow flow path corresponding region 938a is removed, and an anisotropic wet etching is performed with an alkaline aqueous solution. By this treatment, as illustrated in
Next, in a common liquid chamber forming step ST93, a portion of the hard mask film 951 corresponding to a common liquid chamber corresponding region 940a of the nozzle plate side surface 30b is removed and an anisotropic wet etching is performed with an alkaline aqueous solution. By this treatment, as illustrated in
When anisotropic wet etching is performed around the through-hole after forming the through-hole, the wall in the vicinity of the opening of the through-hole is obliquely etched. Therefore, the wall surface of the inlet portion from the common liquid chamber 940 toward the supply flow path 932 has a sagging shape 932b which is lowered to the supply flow path 932 side. In addition, a sagging shape 932c which is lowered to the supply flow path 932 side is formed also in the partition wall between the supply flow paths 932. Here, the depth of the sagging shape of the supply flow path 932 is set to a depth deeper among the depth of the sagging shape 932b and the depth of the sagging shape 932c.
The depth of sagging shape of the supply flow path 932 varies depending on anisotropic wet etching time, temperature and alkali concentration of the etchant, impurities contained in the etchant, and the like. Therefore, it is difficult to make the depth of the sagging shape of the supply flow path 932 constant. Such a problem is more conspicuous when narrowing the interval between the adjacent supply flow paths 32 in order to increase the resolution of the printed image.
When the depth of the sagging shape varies, the supply side inertance varies, which is the inertance of the liquid flow path on the side supplying the liquid to the pressure chamber. When the supply side inertance varies, it is difficult to control the weight of the liquid droplet ejected from the nozzle.
Inertance is a parameter representing fluid movement difficulty. When the liquid ejecting head has the vibration plate, the amount of liquid movement with respect to volume change of the vibration plate is determined by inertance.
In general, inertance is defined by the following equation.
M=ρL/S (1)
Where, M represents inertance, p represents the density of the fluid, L represents the length of the flow path, and S represents the cross-sectional area of the flow path.
According to Equation (1), as the liquid flow path is narrowed, the inertance M increases and the liquid is unlikely to flow. As the liquid flow path is longer, the inertance M increases and the liquid is unlikely to flow.
The weight of the liquid droplet from the nozzle is determined by the volume change amount of the vibration plate and the following discharge efficiency.
E=Ms/(Mn+Ms) (2)
Where, E represents the discharge efficiency, Ms represents the supply side inertance, and Mn represents the nozzle side inertance which is the inertance of the liquid flow path on the side from which the liquid is sent from the pressure chamber to the nozzle.
According to Equation (2), for example, when the nozzle side inertance Mn decreases by expanding the liquid flow path on the nozzle side, the discharge efficiency E increases, and when the supply side inertance Ms increases by narrowing the liquid flow path on the supply side, the discharge efficiency E increases.
When a liquid droplet is ejected from the nozzle, the liquid corresponding to the liquid droplet is supplied to the pressure chamber. Delay in supply of the liquid to the pressure chamber may occur due to the flow path resistance of the liquid flow path on the supply side. When the flow path resistance of the liquid flow path on the supply side is large and the liquid droplet is repeatedly ejected from the nozzle, the supply of the liquid to the pressure chamber cannot be made in time, and the weight of the liquid droplet ejected from the nozzle is small. When the cross-sectional area of the liquid flow path on the supply side is made small in order to increase the supply side inertance Ms, the flow path resistance of the liquid flow path on the supply side increases, so that there is a possibility that the above-described weight reduction occurs. When the cross-sectional area of the liquid flow path on the supply side is increased, although the flow path resistance of the liquid flow path on the supply side is decreased, there is a possibility that the discharge performance of the bubbles may decrease due to a decrease in the flow speed of the liquid. Therefore, in order to achieve both high supply side inertance Ms and good discharge performance of the bubbles, it is preferable to keep constant the shape of the liquid flow path on the supply side.
In the specific example, by using the insulating layer 141 of the multilayer substrate 30, the sagging shape of the supply flow path 32 is suppressed, and variations in supply side inertance are reduced. In addition, by allowing the inlet portion of the supply flow path 32 to be narrower than the other portions, the bubble attached to the wall surface of the inlet portion of the supply flow path 32 is likely to be discharged at the time of cleaning.
When bonding a substrate having a supply flow path which has not sagging shaped to a substrate having a common liquid chamber with an adhesive, it is required to bond these substrates so that the mass of adhesive does not get mixed in the liquid flow path, and a treatment for managing the accuracy of the bonding position is required. As the number of manufacturing steps for that purpose increases, the manufacturing cost increases, and it is also expected to increase the cost because the yield of the substrate decreases to ensure the accuracy of the bonding position.
Here, Reference numeral D2 is a second direction that intersects with the first direction D1. The second direction D2 of the specific example is a direction included in the direction along the multilayer substrate 30, a direction passing through two projection portions 300 which face each other in a plan view as illustrated in
In a plan view illustrated in
As illustrated in
The first portion 310 includes the first facing portion 311 protruding toward the inside of the supply flow path 32 from the second portion 320 in a facing wall portion facing the liquid chamber wall portion 33 across the supply flow path 32. The first facing portion 311 is at a position including the insulating layer 141 in the facing wall portion 34. In addition, the first portion 310 includes the second facing portion 312 protruding toward the inside of the supply flow path 32 from the second portion 320 in the liquid chamber wall portion 33. The second facing portion 312 is at a position facing the first facing portion 311.
The supply flow path 32 includes the first inclined portion 340 having the second wall surface 341 inclined with respect to the first direction D1 between the first facing portion 311 and the second portion 320. The first inclined portion 340 has an inclination inside the supply flow path as the first inclined portion 340 approaches the first facing portion 311. In addition, the supply flow path 32 includes the second inclined portion 350 having the third wall surface 351 inclined with respect to the first direction D1 between the second facing portion 312 and the second portion 320. The second inclined portion 350 has an inclination inside the supply flow path 32 as the second inclined portion approaches the second facing portion 312. In the specific example, the pressure chamber substrate side surface 30a, which is the front surface of the second flow path arrangement layer 132 made of silicon single crystal, is a (110) plane and both the second wall surface 341 and the third wall surface 351 are (111) planes. The first inclined portion 340 is separated from the coupling portion J1 between the supply flow path 32 and the pressure chamber 12 and the second portion 320 is provided between the first inclined portion 340 and the coupling portion J1. The second inclined portion 350 is separated from the coupling portion J1 between the supply flow path 32 and the pressure chamber 12 and the second portion 320 is provided between the second inclined portion 350 and the coupling portion J1.
The range 345 from the insulating layer 141 to the first inclined portion 340 in the supply flow path 32 includes the intermediate position 346 in the first direction D1 in the multilayer substrate 30. In the example illustrated in
As described above, the combination of the first inclined portion 340 and the first facing portion 311 and the combination of the second inclined portion 350 and the second facing portion 312 constitute the projection portion 300 protruding from the second portion 320 to the inside of the supply flow path 32. As described above, the range of the projection portion 300 in the first direction D1 in the multilayer substrate 30 includes the intermediate position 346 in the first direction D1 in the multilayer substrate 30.
An extension wall portion 35 arranged in the direction D3 opposite to the first direction D1 from the facing wall portion 34 is a portion of the wall of the common liquid chamber 40. The extension wall portion 35 illustrated in
As illustrated in
In addition, since the second width W2 of the second portion 320 of the supply flow path 32 is wider than the first width W1 of the first portion 310 in the inlet portion, the flow path resistance of the supply flow path 32 does not excessively increase and the weight of the liquid droplet Q0 is suppressed from decreasing even when the liquid droplet now abandoned Q0 is repeatedly ejected from the nozzle 81.
As illustrated in
As illustrated in
When the bubble remains in the supply flow path 32 as described above, the bubble affects the ejection of the liquid droplet Q0, so that a treatment of removing the bubble from the liquid flow path is performed by a cleaning device (not illustrated). The cleaning device has a cap that covers the nozzle surface 80b, sucks air in the cap, and applies a negative pressure of, for example, approximately −20 kPa to −60 kPa to the nozzle surface 80b to forcibly suck the liquid Q1 from the nozzle 81. As a result, the flow of the liquid Q1 in the first direction D1 occurs in the supply flow path 32.
In this specific example, since there are the first inclined portion 340 and the second inclined portion 350 that gradually expand from the narrow first portion 310 toward the second portion 320 in the supply flow path 32, the liquid Q1 is unlikely to stagnate between the first portion 310 and the second portion 320 when the liquid Q1 flows in the supply flow path 32 in the first direction D1 at the time of cleaning or the like. In particular, the first angle AN1 and the second angle AN2 are acute angles, and the flow of the liquid Q1 is likely to be slow in the vicinity of these angles AN1 and AN2. The first inclined portion 340 is disposed in the direction D3 opposite to the first direction D1 from the first angle AN1, and the second inclined portion 350 is disposed in the direction D3 opposite to the first direction D1 from the second angle AN2. Therefore, stagnation of the liquid Q1 is effectively suppressed, the flow of the liquid Q1 is improved, and the bubble is likely to flow out. Therefore, the residual bubbles in the supply flow path 32 are suppressed.
In addition, as illustrated in
Furthermore, since there is the third inclined portion 360 that gradually extends toward the inside of the common liquid chamber 40 from the third portion 330 toward the first portion 310 on the extension wall portion 35 of the common liquid chamber 40. Therefore, when the liquid Q1 flows from the common liquid chamber 40 to the supply flow path 32 at the time of cleaning or the like, the flow improves and the bubbles are guided by the third inclined portion 360 and are likely to get over the first portion 310. Therefore, the bubbles remaining in the inlet portion of the supply flow path 32 are suppressed.
As described above, in the specific example, it is possible to reduce the variation of the supply side inertance, to suppress the weight variation of the liquid droplet Q0 from the nozzle 81, to suppress the decrease in the weight of the liquid droplet Q0 when repeatedly ejecting the liquid droplet Q0 from the nozzle 81, and to improve the discharge performance of the bubbles in the supply flow path.
Next, with reference to
First, in a hard mask forming step ST1, a treatment is performed of forming a hard mask film 151 on the entire surface of the pressure chamber substrate side surface 30a and the nozzle plate side surface 30b, which are the front surfaces of the base substrate 100.
Next, in a first patterning step ST2, as illustrated in
Next, in the second patterning step ST3, as illustrated in
Next, in an ICP mask forming step ST4, as illustrated in
The ICP mask forming step ST4 may include a third photoresist forming step and a third photoresist patterning step. In the third photoresist forming step, a treatment is performed of applying photoresist on both surfaces of the substrate 101 being processed. In the third photoresist patterning step, a treatment is performed of removing the third photoresist in regions corresponding to the first prepared hole 153a and the second prepared hole 153b in the photoresist by exposure or the like.
Next, in a prepared hole formation step ST5, as illustrated in
For forming the first prepared hole 153a and the second prepared hole 153b, ICP, laser, or the like can be used. In an etching apparatus using ICP, a material to be etched is processed by etching using plasma. When the material to be etched is silicon, gases such as tetrafluoromethane represented by the molecular formula CF4, trifluoromethane represented by the molecular formula CHF3, and the like can be used as the etchant. Although not particularly limited, when forming the first prepared hole 153a, and ICP treatment is performed on the side of the nozzle plate side surface 30b, it is possible to form the first prepared holes 153a reaching the insulating layer 141 with respect to the first flow path arrangement layer 131. When forming the second prepared hole 153b, and ICP treatment is performed on the side of the pressure chamber substrate side surface 30a, it is possible to form the second prepared hole 153b reaching the insulating layer 141 with respect to the second flow path arrangement layer 132. In the treatment of ICP, the insulating layer 141 remains without being etched. For forming the first prepared hole 153a and the second prepared hole 153b, a laser may be used in combination with ICP.
When performing anisotropic wet etching on silicon crystals, the etching rate of the (111) plane is lower than that of the (110) plane and the (100) plane, and etching is difficult. The front surface of the side wall in the first prepared hole 153a and the front surface of the side wall in the second prepared hole 153b are aligned with the (111) plane along the first direction D1. When anisotropic wet etching is performed on the first flow path arrangement layer 131 and the second flow path arrangement layer 132 in a later step, in a direction orthogonal to the first direction D1, the side walls of the first prepared hole 153a and the second prepared hole 153b are only etched slowly after expanding in accordance with the position of the hard mask film 151. In addition, since the insulating layer 141 remains in the above-described anisotropic wet etching, a (111) plane inclined with respect to the first direction D1 appears in a portion of the hole wall in the vicinity of the insulating layer 141. Therefore, the first prepared hole 153a and the second prepared hole 153b are formed in the substrate 101 being processed, so that the projection portion 300 having the inclined surface of the (111) plane with respect to the nozzle communication flow path 31 and the supply flow path 32 is formed more reliably in a later step.
Next, in an ICP mask removal step ST6, as illustrated in
Next, in a first liquid flow path forming step ST7, as illustrated in
Since the surfaces of the first flow path arrangement layer 131 and the second flow path arrangement layer 132 are (110) planes, portions which are not covered with the hard mask film 151 are etched relatively quickly. In
In the hole expanding from the first prepared hole 153a and the second prepared hole 153b, the front surface of the side wall is along the first direction D1 and is a (111) plane which is hard to etch. In addition, since the insulating layer 141 remains in the anisotropic wet etching, a (111) plane inclined with respect to the first direction D1 appears in a portion of the hole wall in the vicinity of the insulating layer 141. The inclined (111) plane appearing in the second flow path arrangement layer 132 is the second wall surface 341 of the first inclined portion 340 and the third wall surface 351 of the second inclined portion 350 illustrated in
Next, in a third hard mask removing step ST8, as illustrated in
Next, in a second liquid flow path forming step ST9, as illustrated in
Regarding the hole formed in the supply flow path corresponding region 151b of the second flow path arrangement layer 132 illustrated in
Next, in a fourth hard mask removing step ST10, as illustrated in
Thereafter, in order to protect the liquid flow path formed on the multilayer substrate 30 from the liquid, although not illustrated, a protective film forming step may be performed of forming a protective film on the front surface of the liquid flow path formed in the multilayer substrate 30. As the protective film, a material having liquid resistance such as ink resistance, for example, a material having alkali resistance such as tantalum oxide represented by TaOx can be used. The thickness of the protective film is not particularly limited, and can be set to approximately 30 to 70 nm.
In order to manufacture the liquid ejecting head 1 from the obtained multilayer substrate 30, for example, a pressure chamber substrate bonding step, a protective substrate bonding step, a case head bonding step, a nozzle plate bonding step, and a sealing plate bonding step are sufficient. In the pressure chamber substrate bonding step, a treatment is performed of bonding the pressure chamber substrate side surface 30a of the multilayer substrate 30 to the multilayer substrate side surface 10b of the pressure chamber substrate 10. In the protective substrate bonding step, a treatment is performed of bonding the protective substrate side surface 10a of the pressure chamber substrate 10 to the protective substrate 50. In the case head bonding step, a treatment is performed of bonding the pressure chamber substrate side surface 30a of the multilayer substrate 30 to the case head 70. In the nozzle plate bonding step, a treatment is performed of bonding the nozzle plate side surface 30b of the multilayer substrate 30 to the nozzle plate 80. In the sealing plate bonding step, a treatment is performed of bonding the nozzle plate side surface 30b of the multilayer substrate 30 to the sealing plate 90. These bonding can be performed using, for example, an adhesive.
By using the SOI substrate for forming the multilayer substrate 30, the first facing portion 311 including the insulating layer 141 and the second facing portion 312 are formed in the supply flow path 32, and the inlet portion of the supply flow path 32 protrudes inward compared with the second portion 320. Since the first wall surface 33a and the second facing portion 312 of the liquid chamber wall portion 33 are aligned with the position of the insulating layer 141 in the first direction D1, the wall surface of the inlet portion of the supply flow path 32 does not have the sagging shape. As a result, since the sagging shape, which is a factor that the supply side inertance varies, is not formed in the supply flow path 32, the variation of the supply side inertance is reduced, and as a result, the weight variation of the liquid droplet Q0 from the nozzle 81 is suppressed. Here, when bonding the substrate having the liquid flow path in the first flow path arrangement layer 131 to the substrate having the liquid flow path in the second flow path arrangement layer 132 with an adhesive, it is required to bond these substrates so that the mass of adhesive does not get mixed in the liquid flow path, and a treatment for managing the accuracy of the bonding position is required. By using the SOI substrate for forming the multilayer substrate 30, the possibility of the mass of adhesive being mixed in the liquid flow path is eliminated, the accuracy of the position of the liquid flow path is also improved, and the manufacturing cost is suppressed. Furthermore, since the projection portion 300 is aligned with the position of the insulating layer 141, the dimensional accuracy of the supply flow path 32 is improved, and the characteristics of the liquid ejecting head 1 ejecting the liquid droplet Q0 are more stabilized. In addition, by adjusting the position of the insulating layer 141 in the first direction D1, it is possible to dispose the projection portion 300 at a desired position.
In addition, since the second width W2 of the second portion 320 in the supply flow path 32 is wider than the first width W1 of the first portion 310 of the inlet portion, the flow path resistance of the supply flow path 32 does not excessively increase and weight reduction of the liquid droplet Q0 repeatedly ejected from the nozzle 81 is suppressed.
Furthermore, since the first width W1 of the inlet portion of the supply flow path 32 is narrower than the second width W2 of the second portion 320 in the first section SC1 along the first direction D1 and the second direction D2, the bubble adhering to the wall surface of the inlet portion of the supply flow path 32 is likely to be discharged at the time of cleaning. In addition, since the first inclined portion 340 coupled to the first facing portion 311 is present in the supply flow path 32, the residual bubbles in the supply flow path 32 are suppressed, and since the second inclined portion 350 coupled to the second facing portion 312 is present in the supply flow path 32, the residual bubbles in the supply flow path 32 are suppressed. Since the third inclined portion 360 coupled to the first facing portion 311 is present in the extension wall portion 35 of the common liquid chamber 40, the residual bubbles in the inlet portion of the supply flow path 32 are suppressed.
As described above, according to the manufacturing method of the specific example, variations in the supply side inertance is reduced to suppress the weight variation of the liquid droplets from the nozzle, the decrease in the weight of the liquid droplet repeatedly ejected from the nozzle is suppressed, and the liquid ejecting head which improves the discharge performance of the bubbles of the supply flow path can be obtained.
Various manufacturing methods for forming the projection portion 300 illustrated in
For example, as in the manufacturing method illustrated in
The cross section of the substrate 101 being processed immediately after performing the above-described steps ST1 to ST3 is as illustrated in
Thereafter, the multilayer substrate 30 as illustrated in
In addition, as in the manufacturing method illustrated in
The cross section of the substrate 101 being processed immediately after the hard mask forming step ST1 is performed is as illustrated in
Thereafter, in the steps ST4 to ST6 described above, as illustrated in
In the manufacturing method illustrated in
As matter of course, the ink jet type recording apparatus may be a line printer or the like having a line head in which a plurality of nozzles are arranged over the entire width of the print substrate.
In the example illustrated in
Even when the plurality of insulating layers 141 are disposed on the multilayer substrate 30, it is possible to obtain the effect of reducing variations in the supplying side inertance, the effect of suppressing decrease in the weight of the liquid droplet repeatedly ejected from the nozzle, and the effect of improving the discharge performance of the bubbles of the supply flow path.
The liquid ejecting head 1 of another example described above can also be used in the liquid ejecting apparatus 200 illustrated in
First, in the hard mask forming step ST1, a treatment is performed of forming a hard mask film 151 on the pressure chamber substrate side surface 30a and the nozzle plate side surface 30b, which are front surfaces of the base substrate 100. Next, in the first patterning step ST2, a treatment is performed of removing the hard mask film in the nozzle communication flow path corresponding region 151a corresponding to the nozzle communication flow path 31, the supply flow path corresponding region 151b corresponding to the supply flow path 32, and the inflow flow path corresponding region 151c corresponding to the inflow flow path 38 in the hard mask film 151. Next, in the second patterning step ST3, as illustrated in
Next, in the ICP mask forming step ST4, a treatment is performed of disposing the third photoresist 153 on a portion of the pressure chamber substrate side surface 30a and the nozzle plate side surface 30b which is the front surface of the substrate 101 being processed, except for the plurality of prepared holes. Next, in the prepared hole forming step ST5, as illustrated in
Between the first prepared hole 153a and the second prepared hole 153b, the insulating layer 141, the second flow path arrangement layer 132, and the second insulating layer 142 are left. Therefore, in the laser processing step ST31, as illustrated in
Next, in the first liquid flow path forming step ST7, as illustrated in
Next, in the third hard mask removing step ST8, as illustrated in
Next, in the second liquid flow path forming step ST9, as illustrated in
Next, in the fourth hard mask removing step ST10, as illustrated in
Even with the above-described manufacturing method, variations in supply side inertance are reduced, a reduction in weight of liquid droplets repeatedly ejected from the nozzles is suppressed, and the discharge performance of the bubbles in the supply flow path is improved.
The present disclosure can be applied to various applications and various modifications.
For example, the liquid ejecting apparatus is not limited to a printing apparatus dedicated to printing, and may be a facsimile apparatus, a copying apparatus, a multifunction machine having a function other than printing such as facsimile or copying, or the like.
The liquid ejected from the fluid ejecting head includes a fluid such as a solution in which a solute such as a dye is dissolved in a solvent and a sol in which solid particles such as a pigment or a metal particle are dispersed in a dispersion medium. Such liquids include ink, liquid crystal, and the like. The liquid ejecting apparatus includes an apparatus for manufacturing a color filter for a liquid crystal display, an apparatus for manufacturing an electrode for an organic EL display, a biochip manufacturing apparatus, a manufacturing apparatus for forming wiring of a wiring substrate, and the like, in addition to the image recording apparatus such as a printer. Here, the organic EL is an abbreviation for organic electroluminescence.
In the above-described embodiment, although both the first facing portion 311 and the second facing portion 312 protrude inward compared with the second width W2 in the supply flow path 32, one of the first facing portion 311 and the second facing portion 312 may not protrude inward. As long as the first width W1 of the first portion 310 is narrower than the second width W2 of the second portion 320, the bubble attached to the wall surface of the inlet portion of the supply flow path 32 is likely to be discharged at the time of cleaning.
In the above-described embodiment, although the first inclined portion 340 and the second inclined portion 350 are disposed in the supply flow path 32, and the third inclined portion 360 is disposed in the common liquid chamber 40, a case where a portion or all of these inclined portions 340, 350, and 360 is absent is also included in the present technology. Even in this case, as long as the first width W1 of the first portion 310 is narrower than the second width W2 of the second portion 320, the bubble attached to the wall surface of the inlet portion of the supply flow path 32 is likely to be discharged at the time of cleaning.
In the above-described embodiment, although the second wall surface 341 of the first inclined portion 340, the third wall surface 351 of the second inclined portion 350, and the fourth wall surface 361 of the third inclined portion 360 are the (111) planes, a case where these wall surfaces 341, 351, and 361 deviate from the (111) plane is also included in the present technology. Even in this case, as long as the first width W1 of the first portion 310 is narrower than the second width W2 of the second portion 320, the bubble attached to the wall surface of the inlet portion of the supply flow path 32 is likely to be discharged at the time of cleaning. The first angle AN1 and the second angle AN2 for specifying the position of the first portion 310 are not limited to acute angles and may be right angle or obtuse angle. Even when these angles AN1, AN2 are right angles or obtuse angles, the cross section shape of the inlet portion of the supply flow path 32 is close to a circle due to the existence of the first portion 310, so that the residual bubbles in the supply flow path 32 are suppressed.
In the above-described embodiment, although the insulating layer 141 is not left in the first wall surface 33a and the second facing portion 312, a case where the insulating layer 141 remains in the first wall surface 33a and the second facing portion 312 is also included in the present technology. Even in this case, as long as the first width W1 of the first portion 310 is narrower than the second width W2 of the second portion 320, the bubble attached to the wall surface of the inlet portion of the supply flow path 32 is likely to be discharged at the time of cleaning.
The present technology also has the following additional aspects. The parenthesis written in the additional aspect illustrates the reference numeral of the element corresponding to the above-described specific example. As matter of course, each element of the additional aspect is not limited to the specific example indicated by the reference numeral.
A manufacturing method of a flow path substrate (30) having the nozzle communication flow path 31 disposed between the nozzle plate 80 having the nozzle 81 and the pressure chamber substrate 10 having the first pressure chamber 121 to allow the first pressure chamber 121 and the nozzle 81 communicate with each other, in which the pressure chamber substrate 10 has the second pressure chamber 122 disposed next to the first pressure chamber 121 via the partition wall 12a, the flow path substrate (30) has the common liquid chamber 40 communicating with the first pressure chamber 121 and the second pressure chamber 122, the base substrate 100 for forming the flow path substrate (30) includes the first flow path arrangement layer 131, the insulating layer 141 having a material different from a material forming the first flow path arrangement layer 131, and the second flow path arrangement layer 132 having a material different from a material forming the insulating layer 141, in order of arrangement from the nozzle plate 80 side, the flow path substrate (30) includes the liquid chamber wall portion 33 disposed on the side of the second flow path arrangement layer 132 from the common liquid chamber 40, the flow path substrate (30) has the supply flow path 32 via which the common liquid chamber 40 communicates with the first pressure chamber 121, the direction from the common liquid chamber 40 to the first pressure chamber 121 is defined as the first direction D1, and the direction intersecting the first direction D1 is defined as the second direction D2, the method includes a first forming step of forming the substrate 101 being processed having the prepared holes (153a, 153b) thinner than the supply flow path 32 in the region (151b) corresponding to the supply flow path 32 from the base substrate 100, and a second forming step of forming the first portion 310 having the first width W1 at the inlet portion of the supply flow path and the second portion 320 having the second width W2 wider than the first width W1 in the first cross section SC1 along the first direction D1 and the second direction D2 of the supply flow path 32, by aligning the position of the inlet portion of the supply flow path 32 from the common liquid chamber 40 with the position of the insulating layer 141 by performing anisotropic wet etching on the substrate 101 being processed.
Here, the first forming step corresponds to steps ST1 to ST6 illustrated in
According to above Additional Aspect 1, it is possible to provide the flow path substrate for the liquid ejecting head that improves the discharge performance of the bubbles of the supply flow path.
A manufacturing method of a liquid ejecting head 1 including a pressure chamber substrate bonding step of bonding the pressure chamber substrate 10 to the front surface (30a) of the flow path substrate (30) on the side of the pressure chamber substrate 10 obtained by the manufacturing method according to Additional Aspect 1, and a nozzle plate bonding step of bonding the nozzle plate 80 to the front surface (30b) on the side of the nozzle plate 80 of the flow path substrate (30).
According to above Additional Aspect 2, it is possible to provide the liquid ejecting head that improves the discharge performance of the bubbles of the supply flow path.
A manufacturing method of a liquid ejecting apparatus 200, including a liquid ejecting head incorporating step of incorporating the liquid ejecting head obtained by the manufacturing method according to Additional Aspect 2 into the liquid ejecting apparatus 200.
According to above Additional Aspect 3, it is possible to provide the liquid ejecting apparatus including the liquid ejecting head for improving the discharge performance of the bubbles of the supply flow path.
As described above, according to the present disclosure, it is possible to provide a technology such as the liquid ejecting head that improves the discharge performance of the bubbles of the supply flow path according to various aspects. As matter of course, the basic operation and effect described above can be obtained even with a technology formed only of the constituent features according to the independent aspect.
In addition, a configuration in which each of the configurations disclosed in the above examples are mutually replaced or the combination is changed, a configuration in which each of the configurations disclosed in the related art and the above examples are mutually replaced or the combination is changed, and the like can also be implemented. The present disclosure includes these configurations and the like.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2018-117507 | Jun 2018 | JP | national |
