JP2011046041A - Method of manufacturing liquid ejection head, and liquid ejection head - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing a liquid ejection head including a nozzle group formed by juxtaposing a plurality of nozzles, the method reducing variations in ejection characteristics of each nozzle, and to provide the liquid ejection head manufactured by the method. <P>SOLUTION: In a recording head including a nozzle row (nozzle group) formed by juxtaposing the plurality of nozzles, a plurality of pressure chambers formed so as to correspond to the respective nozzles, and a plurality of piezoelectric elements (pressure generating means) disposed so as to correspond to the respective pressure chambers and varying the volume of the pressure chamber, the bore of each nozzle is set based on a displacement amount or frequency characteristics of the corresponding piezoelectric element. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a method of manufacturing a liquid jet head such as an ink jet recording head, and a liquid jet head manufactured by the method, and in particular, a liquid jet having a nozzle group in which a plurality of nozzles are arranged. The present invention relates to a head manufacturing method and a liquid jet head.

  For example, a liquid ejecting apparatus is an apparatus that includes a liquid ejecting head capable of ejecting liquid from a nozzle and ejects various liquids from the liquid ejecting head. A typical example of this liquid ejecting apparatus includes an ink jet recording head (hereinafter simply referred to as a recording head) as a liquid ejecting head, and liquid ink is ejected from a nozzle of the recording head to a recording medium such as recording paper (ejection). An image recording apparatus such as an ink jet printer (hereinafter simply referred to as a printer) that records an image or the like by jetting and landing on a target) can be given. In recent years, liquid ejecting apparatuses have been applied not only to this image recording apparatus but also to various manufacturing apparatuses such as a manufacturing apparatus for color filters such as liquid crystal displays.

  In the recording head, a plurality of nozzles for ejecting ink are provided to form a nozzle row, and a part of the pressure chamber communicating with the nozzle is constituted by a vibration plate, and the vibration plate is deformed by a piezoelectric element as pressure generating means. There is a configuration in which pressure fluctuation is generated in the pressure chamber, and ink is ejected from the nozzle using this pressure vibration. As the pressure generating means, a so-called longitudinal vibration mode piezoelectric element corresponding to each pressure chamber is provided as a unit, or a so-called flexural vibration mode piezoelectric element provided individually for each pressure chamber is used. ing. The piezoelectric element is configured by laminating a piezoelectric material made of PZT (lead zirconate titanate) and an electrode material, and is displaced by applying a voltage between the drive electrode and the common electrode.

  In this type of recording head, there is a high-density nozzle having a nozzle formation pitch of 360 dpi or more in response to a demand for recording a finer and higher-resolution image, and the piezoelectric element corresponding to each nozzle is also formed by extremely fine processing. ing. For this reason, the displacement of the piezoelectric element corresponding to each nozzle may vary, and in this case, the ejection characteristics such as the amount (weight / volume) of the ejected ink and the flying speed of the ink are different between the nozzles. There is a problem that is different. Conventionally, when the variation in displacement of the piezoelectric element is too large to be corrected, the piezoelectric element has been discarded as a defective product. In addition, when the variation in displacement is not so great as to be a defective product, a configuration is proposed in which a correction circuit having a capacitor is electrically connected to the piezoelectric element and the capacitance is adjusted by controlling the correction circuit. (See Patent Document 1).

JP 2000-351209 A

  However, in the configuration in which the correction circuit is connected to the piezoelectric element as described above, there are problems that the cost is increased and the head size is increased.

  The present invention has been made in view of such circumstances, and an object thereof is to reduce variation in ejection characteristics of each nozzle in a liquid ejection head including a nozzle group in which a plurality of nozzles are arranged in a row. It is an object of the present invention to provide a method of manufacturing a liquid ejecting head capable of performing the above and a liquid ejecting head manufactured by the method.

The present invention has been proposed in order to achieve the above object, and includes a nozzle group in which a plurality of nozzles are arranged, a plurality of pressure chambers formed corresponding to each nozzle, and each pressure chamber. A plurality of pressure generating means arranged correspondingly and changing the volume of the pressure chamber, and driving the pressure generating means to change the volume of the pressure chamber to eject liquid from the corresponding nozzle A method for manufacturing an ejection head, comprising:
A characteristic measuring step of measuring a displacement amount or a frequency characteristic as a characteristic of each pressure generating means;
A nozzle forming step of forming, on the nozzle substrate, a nozzle having an opening diameter determined based on the characteristics of the corresponding pressure generating means;
It is characterized by including.

  According to the above configuration, the nozzle having the opening diameter determined based on the characteristics of the corresponding pressure generating means is formed on the nozzle substrate, that is, the nozzles constituting the nozzle group are opened according to the characteristics of the pressure generating means. Since the diameters are different, it is possible to suppress variations in ejection characteristics between the nozzles due to variations in characteristics between the pressure generating means.

Further, the present invention provides a nozzle group in which a plurality of nozzles are arranged,
A plurality of pressure chambers formed corresponding to each nozzle;
A plurality of pressure generating means arranged corresponding to each pressure chamber and changing the volume of the pressure chamber;
A liquid ejecting head that ejects liquid from a corresponding nozzle by driving the pressure generating means to vary the volume of the pressure chamber,
The opening diameter of each nozzle is determined based on the displacement amount or frequency characteristic of the corresponding pressure generating means.

  According to the above configuration, since the opening diameter of each nozzle is determined based on the displacement amount or frequency characteristic of the corresponding pressure generating means, the variation in the ejection characteristics between the nozzles due to the characteristic variation between the pressure generating means. Is suppressed.

Further, the present invention provides a nozzle group in which a plurality of nozzles are arranged, a plurality of pressure chambers formed corresponding to each nozzle, and a volume of the pressure chambers arranged corresponding to each pressure chamber. A method of manufacturing a liquid ejecting head that ejects liquid from a corresponding nozzle by driving the pressure generating means to vary the volume of the pressure chamber.
And a nozzle forming step of forming, on the nozzle substrate, a nozzle having an opening diameter determined based on a predetermined angle of the nozzle forming surface with respect to the bottom surface of the device when the liquid jet head is attached to the liquid jet device.

  According to the above configuration, since the nozzle having an opening diameter determined based on the expected mounting angle of the nozzle forming surface with respect to the apparatus bottom surface is formed on the nozzle substrate, regardless of the mounting posture of the liquid ejecting head with respect to the liquid ejecting apparatus, It is possible to suppress variations in ejection characteristics between nozzles.

Furthermore, the present invention provides a nozzle group in which a plurality of nozzles are arranged,
A plurality of pressure chambers formed corresponding to each nozzle;
A plurality of pressure generating means arranged corresponding to each pressure chamber and changing the volume of the pressure chamber;
A liquid ejecting head that ejects liquid from a corresponding nozzle by driving the pressure generating means to vary the volume of the pressure chamber,
The opening diameter of each nozzle is determined based on a predetermined angle of the nozzle forming surface with respect to the bottom surface of the device when the liquid ejecting head is attached to the liquid ejecting device.

  According to the above configuration, since the opening diameter of each nozzle is determined based on the planned mounting angle of the nozzle forming surface with respect to the bottom surface of the liquid ejecting head, regardless of the mounting posture of the liquid ejecting head with respect to the liquid ejecting device, It is possible to suppress variations in ejection characteristics between nozzles.

FIG. 3 is a perspective view illustrating a configuration of a printer. FIG. 2 is an exploded perspective view illustrating a configuration of a recording head. FIG. 3 is a cross-sectional view of a main part for explaining the configuration of a recording head. It is a perspective view explaining the structure of a vibrator | oscillator unit. It is a principal part top view explaining the structure of a nozzle substrate. It is a graph explaining the difference in line width when a ruled line is printed using each nozzle. It is a figure explaining a nozzle formation process. It is the table | surface which showed the example about adjustment of a nozzle opening diameter. It is sectional drawing explaining the structure of the printer in 2nd Embodiment. It is the table | surface which showed the example about adjustment of the nozzle opening diameter in 2nd Embodiment.

  Hereinafter, an embodiment for carrying out the present invention will be described with reference to the accompanying drawings. In the embodiments described below, various limitations are made as preferred specific examples of the present invention. However, the scope of the present invention is not limited to the following description unless otherwise specified. However, the present invention is not limited to these embodiments. In the following, an ink jet recording head (hereinafter referred to as a recording head) mounted on an ink jet recording apparatus (hereinafter referred to as a printer) will be described as an example of the liquid jet head of the present invention.

  FIG. 1 is a perspective view showing the configuration of the printer 1. The printer 1 has a recording head 2 which is a kind of liquid ejecting head and a carriage 4 to which an ink cartridge 3 is detachably attached, a platen 5 disposed below the recording head 2, and a carriage 4 ( A carriage moving mechanism 7 that reciprocates the recording head 2) in the paper width direction of the recording paper 6 as a liquid landing target, that is, the main scanning direction, and a sub-scanning direction (nozzle described later) that intersects the main scanning direction. A paper feed mechanism 8 (a kind of moving means) for transporting the recording paper 6 in the (row direction) is schematically configured. A configuration in which the ink cartridge 3 is mounted on the housing side of the printer 1 and is supplied to the recording head 2 via an ink supply tube may be employed.

  The carriage 4 is attached while being supported by a guide rod 9 installed in the main scanning direction, and is configured to move in the main scanning direction along the guide rod 9 by the operation of the carriage moving mechanism 7. ing. The position of the carriage 4 in the main scanning direction is detected by the linear encoder 10, and an encoder pulse as a detection signal is transmitted to a printer controller (not shown). Thereby, the recording operation (jetting operation) by the recording head 2 is controlled while recognizing the scanning position of the carriage 4 (recording head 2) based on the encoder pulse.

  A home position serving as a scanning base point is set in an end area outside the recording area within the moving range of the carriage 4 (right side in FIG. 1). In the home position in the present embodiment, a capping member 11 for sealing the nozzle forming surface (nozzle substrate 25: see FIG. 2) of the recording head 2 and a wiper member 12 for wiping the nozzle forming surface are arranged. Yes. The printer 1 moves forward when the carriage 4 (recording head 2) moves from the home position toward the opposite end, and when the carriage 4 returns from the opposite end to the home position. And so-called bidirectional recording in which characters, images, etc. are recorded on the recording paper 6 in both directions.

FIG. 2 is an exploded perspective view of the recording head 2, and FIG. 3 is a cross-sectional view of the main part of the recording head 2. FIG. 4 is a perspective view for explaining the configuration of the vibrator unit 18.
The illustrated recording head 2 includes a vibrator unit 18 (see FIG. 4) in which a plurality of piezoelectric elements 15 (a kind of pressure generating means in the present invention) arranged in a row and a fixed plate 17 are unitized. And a case 19 in which the vibrator unit 18 can be accommodated, and a flow path unit 20 joined to the front end surface of the case 19.

  First, the vibrator unit 18 will be described. As shown in FIG. 4, the piezoelectric elements 15 constituting the piezoelectric element group 16 are formed in a comb-like shape elongated in the vertical direction. Each piezoelectric element 15 is configured as a longitudinal vibration type piezoelectric element that can expand and contract in the longitudinal direction (element longitudinal direction). In these piezoelectric elements 15, the fixed end 21 that does not expand and contract is joined to the fixed plate 17, so that the free end 22 protrudes outward from the front end edge of the fixed plate 17. That is, the piezoelectric element 15 is supported on the fixed plate 17 in a so-called cantilever state. The fixed end 21 is provided with a length shorter than the length of the fixed plate 17 and is joined to the front side portion (tip side portion) of the fixed plate 17. In addition, the front-end | tip of the free end part 22 in each piezoelectric element 15 is joined to the island part 36 (diaphragm part) of the flow path unit 20, respectively (refer FIG. 3).

  The flexible cable 14 for applying a drive signal to the piezoelectric element 15 of the vibrator unit 18 is electrically connected to the piezoelectric element 15 on the side surface of the fixed end 21 that is opposite to the fixed plate 17. Further, the fixing plate 17 that supports each piezoelectric element 15 is configured by a plate-like member having rigidity capable of receiving a reaction force from the piezoelectric element 15. In this embodiment, it is made of a stainless steel plate having a thickness of about 1 mm.

  Next, the flow path unit 20 will be described. As shown in FIGS. 2 and 3, the flow path unit 20 includes a nozzle substrate 25, a flow path substrate 26, and a vibration plate 27. The nozzle substrate 25 is placed on one surface of the flow path substrate 26 and the vibration plate 27. Are arranged and laminated on the other surface of the flow path substrate 26 on the side opposite to the nozzle substrate 25, and are integrated by bonding or the like.

  The nozzle substrate 25 is a thin plate material in which a plurality of nozzles 28 are arranged in rows at a pitch corresponding to the dot formation density. In this embodiment, the nozzle substrate 25 is manufactured from a silicon single crystal substrate which is a kind of crystalline base material, and a plurality of nozzles 28 are opened in a row by etching. These nozzles 28 constitute a nozzle row (a kind of nozzle group), and this nozzle row is provided on the nozzle substrate 25 side by side in two rows. The manufacturing process of the nozzle substrate 25 will be described later.

  The flow path substrate 26 is a plate-like member in which an ink flow path including a common ink chamber (reservoir) 31, an ink supply port 32, and a pressure chamber 33 is formed. Specifically, the flow path substrate 26 is formed in a plural number in a state where the empty portions that become the pressure chambers 33 are partitioned by the partition walls so as to correspond to the respective nozzles 28, and the empty spaces that become the ink supply ports 32 and the common ink chamber 31. It is the plate-shaped member which formed the part. The flow path substrate 26 of the present embodiment is manufactured by etching a silicon single crystal substrate.

  The pressure chamber 33 is formed as an elongated chamber in a direction orthogonal to the direction in which the nozzles 28 are arranged, and the ink supply port 32 has a flow path width that communicates between the pressure chamber 33 and the common ink chamber 31. It is formed as a narrow constriction. The common ink chamber 31 is a chamber for supplying the ink stored in the ink cartridge 3 to each pressure chamber 33 and communicates with the corresponding pressure chamber 33 through the ink supply port 32.

  The diaphragm 27 is a composite plate material having a double structure in which a resin film 35 such as PPS (polyphenylene sulfide) is laminated on a metal support plate 34 such as stainless steel, and seals one opening surface of the pressure chamber 33. In addition to functioning as a diaphragm portion that stops, it also functions as a compliance portion that seals one opening surface of the common ink chamber 31. Then, the portion that functions as the diaphragm portion, that is, the support plate 34 corresponding to the pressure chamber 33 is etched, the portion is removed in an annular shape, and the tip of the free end portion 22 of the piezoelectric element 15 is joined. An island portion 36 is formed. Similar to the planar shape of the pressure chamber 33, the island portion 36 has a block shape elongated in a direction orthogonal to the direction in which the nozzles 28 are arranged, and the resin film 35 around the island portion 36 functions as an elastic film. . In addition, as for the portion functioning as the compliance portion, that is, the portion corresponding to the common ink chamber 31, the portion of the support plate 34 is removed by etching to make only the resin film 35.

  Since the tip end face of the piezoelectric element 15 is joined to the island part 32, the volume of the pressure chamber 33 can be changed by expanding and contracting the free end part of the piezoelectric element 15. A pressure fluctuation occurs in the ink in the pressure chamber 33 along with the volume fluctuation. The recording head 2 ejects ink from the nozzles 28 using this pressure fluctuation.

  FIG. 5 is a plan view illustrating the configuration of the nozzle substrate 25. Each nozzle 28 is schematically given a serial number (# 1 to # 360) in order to distinguish it from each other. The nozzle substrate 25 in the present embodiment constitutes a nozzle row (a type of nozzle group) in which 360 nozzles 28 that eject ink (a type of liquid in the present invention) are arranged in parallel with the conveyance direction of the recording paper 2. Further, a plurality of nozzle rows (for example, two rows) are provided in a direction (main scanning direction) orthogonal to the conveyance direction of the recording paper 2. In the nozzle row in this embodiment, the nozzles 28 are opened at a formation pitch of 360 dpi, for example. The opening diameter on the ejection side of each nozzle 28 constituting one nozzle row is set to a value corresponding to the characteristics of the piezoelectric element 15. Hereinafter, this point will be described.

  Here, in the recording head 2 according to the present invention, the piezoelectric element 15 is also formed by extremely fine processing corresponding to the formation pitch of the nozzles 28. For this reason, the displacement of the piezoelectric element 15 corresponding to each nozzle 28 may be different. In this case, if no measures are taken, there is a problem that the ejection characteristics such as the amount (weight / volume) of ink ejected from the nozzle 28 and the flying speed of the ink differ among the nozzles. If the ejection characteristics differ between the nozzles, the image quality of an image printed on recording paper or the like may be degraded.

  FIG. 6 is a graph for explaining the difference in the width of the ruled line when ink is individually ejected from each nozzle 28 constituting the same nozzle row and the ruled line is printed on recording paper or the like. The attached nozzle number and the vertical axis indicate the width of the ruled line (line width). A drive pulse having the same waveform for each piezoelectric element 15 is commonly used as the drive pulse for expanding and contracting the piezoelectric element 15 when ink is ejected. In FIG. 6, when the piezoelectric element 15 corresponding to each nozzle is driven to expand and contract with the drive pulse having the same waveform, the displacement of the piezoelectric element 15 corresponding to the nozzle # 1 is the smallest, and the nozzle number increases. An example is shown in which the displacement of the corresponding piezoelectric element 15 is large, and the displacement of the piezoelectric element 15 corresponding to the nozzle 28 of # 360 is the largest. If no measures are taken, when the ruled line is printed under the same conditions (the same type of ink, the same waveform drive pulse, and the ejection of the nozzle alone), the line width of the ruled line printed by the nozzle # 1 is The line width becomes thicker as the nozzle number increases, and the line width of the ruled line printed by the # 360 nozzle 28 becomes the thickest.

  In consideration of such variations in the characteristics of the piezoelectric elements, in the recording head 2 according to the present invention, the opening diameter of each nozzle 28 is determined based on the characteristics of the corresponding piezoelectric element 15. The characteristic of the piezoelectric element 15 directly related to the ejection characteristics of the nozzle 28 is a displacement amount when a predetermined drive signal is applied, or a frequency characteristic (resonance frequency) of the piezoelectric element.

  In the present embodiment, before the process of forming the nozzles 28 on the nozzle substrate 25, the characteristics of the piezoelectric element 15 are acquired in advance (characteristic measurement process). In this characteristic measurement step, the displacement amount or frequency characteristic of the piezoelectric element 15 is measured. In the case of a configuration for measuring the displacement amount of the piezoelectric element 15, for example, a non-contact measuring machine such as a laser Doppler vibrometer or a capacitance meter is used. In the case of measurement using a laser Doppler vibrometer, the displacement portion of the piezoelectric element 15 to be measured is irradiated with laser light, and the displacement amount of the piezoelectric element 15 is obtained by using the frequency change of the irradiated light and reflected light. Further, in the case of a configuration in which the resonance frequency of the piezoelectric element is measured as the frequency characteristic, the impedance frequency characteristic is obtained with an impedance analyzer or the like while changing the frequency of the voltage applied to the piezoelectric element 15, and the resonance frequency is derived from the obtained frequency characteristic. can do. There is a correlation between the resonance frequency and the displacement amount of the piezoelectric element 15, and the displacement amount tends to increase as the resonance frequency decreases, and conversely, the displacement amount tends to decrease as the resonance frequency increases. Therefore, each displacement amount can be estimated by measuring the resonance frequency of each piezoelectric element 15.

Then, after the characteristic measurement process is performed, a process of forming the nozzles 28 on the nozzle substrate 25 is performed (nozzle formation process). In addition, regarding the formation method of the nozzle 28, it is not restricted to what is illustrated below, A various method is employable.
FIG. 7 is a cross-sectional view of the main part for explaining the flow of the nozzle forming process. First, a photoresist 41 is formed on the entire surface of the silicon substrate 40 to be the nozzle substrate 25, and a first nozzle hole pattern mask 42 is formed thereon (FIG. 7A). Next, the photoresist 41 is exposed and developed through the mask 42 to form a resist pattern in which an opening 43 is provided in a portion corresponding to the first nozzle hole 28a (FIG. 7B). ). Then, anisotropic dry etching is performed on the silicon substrate 40 using the resist pattern as an etching mask to form the first nozzle holes 28a. Thereafter, the resist pattern is removed (FIG. 7C).

  Here, the inner diameter D1 of the first nozzle hole 28a is the final opening diameter of the nozzle 28. For this reason, the inner diameter D1 of the first nozzle hole 28a is adjusted according to the result obtained in the characteristic measurement step. That is, the inner diameter D1 of the first nozzle hole 28a is decreased as the displacement amount of the piezoelectric element 15 corresponding to the nozzle to be processed is increased or the resonance frequency of the piezoelectric element 15 corresponding to the nozzle 28 is decreased. As the displacement amount of the piezoelectric element 15 corresponding to the nozzle to be processed is smaller or the resonance frequency of the piezoelectric element 15 corresponding to the nozzle is larger, the inner diameter D1 of the first nozzle hole 28a is adjusted to be larger. The Therefore, the inner diameter D1 of the first nozzle 28a differs among the nozzles according to the characteristics of the corresponding piezoelectric element 15.

  FIG. 8 is a table showing an example of adjustment of the nozzle opening diameter (the inner diameter D1 of the first nozzle 28a). In the figure, the mask is the type of mask pattern when forming the first nozzle hole. For example, when the characteristic measurement process shows that there is no difference (0%) in the characteristics (displacement amount or resonance frequency) of the piezoelectric elements 15 corresponding to the nozzles 28 from # 1 to # 360, it corresponds to the nozzle. The first nozzle hole 28a is formed using the mask A having a constant opening size. As a result, the opening diameter of each nozzle 28 is aligned with the inner diameter of the # 1 nozzle 28 as a reference (100%). Further, for example, as a result of the measurement in the characteristic measurement step, a difference of 2% (displacement amount) of the characteristic of the piezoelectric element 15 corresponding to the nozzle 28 of # 360 with respect to the characteristic of the piezoelectric element 15 corresponding to the nozzle 28 of # 1. In the case of + 2% in the case and -2% in the case of the resonance frequency), the first nozzle hole 28a is formed using the mask C. In the vibrator unit 18 in the present embodiment, the piezoelectric element 15 (piezoelectric element corresponding to the nozzle # 1) located at one end in the element arrangement direction to the piezoelectric element 15 (other than the nozzle 28 # 360) at the other end. The characteristic difference tends to increase linearly toward the piezoelectric element. In accordance with this tendency, the diameter of the opening of the mask C gradually decreases from that corresponding to the # 1 nozzle 28 to that corresponding to the # 360 nozzle 28. As a result, the opening diameter of each nozzle 28 (the inner diameter D1 of the first nozzle hole 28a) gradually decreases from the # 1 nozzle 28 as the reference toward the # 360 nozzle 28, and the # 360 nozzle 28 Is adjusted to 90% of the inner diameter (100%) of the nozzle # 1. Thus, if a plurality of mask patterns are prepared in accordance with the characteristic difference between the piezoelectric elements, the nozzle 28 having an opening diameter determined based on the characteristics of the piezoelectric element 15 can be easily formed. The reference is not limited to the # 1 nozzle 28, and the nozzle 28 corresponding to the piezoelectric element 15 exhibiting the most desirable characteristics may be used as a reference.

  Next, a photoresist 44 is formed on the entire surface of the silicon substrate 40 in which the first nozzle holes 28a are formed, and a mask 45 for a second nozzle pattern is further formed (FIG. 7D). Exposure and development are performed through the mask 45 to form a resist pattern in which an opening 46 is provided in a portion corresponding to the second nozzle hole 28b (FIG. 7E). Subsequently, anisotropic dry etching is performed using this resist pattern as an etching mask to form second nozzle holes 28b (FIG. 7F). The inner diameter D2 of the second nozzle hole 28b is adjusted to be larger than the inner diameter D1 of the first nozzle hole 28a. The inner diameter D2 of the first nozzle 28a is made uniform among the nozzles. Then, necessary surface treatment such as film formation of a water repellent film is performed on the discharge side surface of the silicon substrate 40 to complete the nozzle substrate 25.

  Through the above steps, the nozzle 28 is formed on the nozzle substrate 25, and the inner diameter D1 of the first nozzle hole 28a, which is the final opening diameter of the nozzle 28, is adjusted to a size according to the characteristics of the corresponding piezoelectric element 15. The As the opening diameter of the nozzle 28 is larger, the amount of ink ejected from the nozzle 28 is increased, and as the opening diameter is smaller, the amount of ink ejected from the nozzle 28 is decreased. By adjusting the opening diameter according to the characteristics of the element 15, it is possible to reduce variations in ejection characteristics regardless of the difference in characteristics between the piezoelectric elements. As a result, it is possible to prevent a deterioration in image quality of an image or the like printed on an ejection target such as recording paper.

The shape of the nozzle 28 is not limited to that exemplified above. For example, in the above example, the nozzle 28 is configured by two stages of nozzle holes by the first nozzle hole 28a and the second nozzle hole 28b. For example, the nozzle 28 is configured by three or more stages of nozzle holes. Also good.
Further, the nozzle substrate 25 is not limited to the one made of a silicon substrate, and may be made of a metal plate such as stainless steel, for example. In the case of this configuration, the nozzle 28 can be manufactured by press working using a punch.

  Further, in the above, for example, the so-called longitudinal vibration type piezoelectric element 15 is exemplified as the pressure generating means. However, the present invention is not limited to this, and the present invention is also applied to a configuration employing, for example, a so-called flexural vibration type piezoelectric element. Is possible.

Next, a second embodiment of the present invention will be described.
FIG. 9 is a cross-sectional view of a printer 1 ′ that employs the recording head 2 ′ in the present embodiment. In this printer 1 ′, built-in components such as the recording head 2 ′ and the platen 5 are inclined with respect to the apparatus bottom surface 48 of the printer 1 ′ for the purpose of reducing the front-rear width of the printer 1 ′ and saving space. This is characterized in that the positions in the vertical direction of the nozzles 28 constituting the nozzle row are different from each other. Since other configurations are the same as those in the first embodiment, description thereof is omitted.

  Assuming that the printer 1 ′ is used in an ideal installation state in which the apparatus bottom surface 48 is horizontal, when the recording head 2 or the like is mounted in an inclined state with respect to the bottom surface 48, each of the nozzle rows is configured. The positions of the nozzles 28 in the vertical direction are different. When the vertical position of each nozzle 28 is different, the meniscus head of each nozzle 28 is also different. As a result, when ink is ejected to each nozzle 28 under the same conditions, the amount of ink ejected from the nozzle 28 in the lower position in the vertical direction is lower, and the position in the vertical direction is higher. The amount of ink ejected as the nozzle 28 increases. In order to prevent such problems, in this embodiment, the inclination angle θ of the nozzle formation surface (discharge-side surface) of the nozzle substrate 25 with respect to the apparatus bottom surface 48 (when the recording head 2 ′ is attached to the printer 1 ′). The opening diameter of each nozzle 28 is determined based on a predetermined angle. In addition, about the process of forming the nozzle 28 in the nozzle board | substrate 25, the same process as the nozzle formation process illustrated in the said 1st Embodiment (FIG. 7) passes.

FIG. 10 is a table showing an example of adjustment of the nozzle opening diameter (the inner diameter D1 of the first nozzle 28a) in the present embodiment. 10 shows that when the nozzle forming surface is inclined with respect to the apparatus bottom surface 48, the # 1 nozzle 28 is disposed at the lowest position in the vertical direction, and the # 360 nozzle 28 is at the highest position in the vertical direction. The example arrange | positioned is shown.
For example, when the inclination angle θ of the nozzle formation surface of the nozzle substrate 25 with respect to the apparatus bottom surface 48 is 0 degree, that is, the nozzle formation surface and the apparatus bottom surface 48 are parallel, the first nozzle hole 28a is formed using the mask A. Is called. In this case, it is assumed that there is no meniscus water head difference between the nozzles 28, so the diameters of the openings corresponding to the nozzles 28 of the mask A are the same. As a result, the opening diameter of each nozzle 28 is aligned with the inner diameter of the # 1 nozzle 28 as a reference (100%). For example, when the inclination angle θ of the nozzle forming surface of the nozzle substrate 25 with respect to the apparatus bottom surface 48 is 40 degrees, the first nozzle hole 28 a is formed using the mask C. The diameter of the opening portion of the mask C gradually decreases from the one corresponding to the nozzle 28 of # 1 to the one corresponding to the nozzle 28 of # 360, and the diameter of the opening portion corresponding to the nozzle 28 of # 360 is , It is 90% of the diameter (100%) of the opening corresponding to the nozzle 28 of # 1. As a result, the opening diameter of each nozzle 28 gradually decreases from the # 1 nozzle 28 as the reference toward the # 360 nozzle 28, and the inner diameter of the # 360 nozzle 28 is smaller than that of the # 1 nozzle 28. The size is adjusted to 90% with respect to the inner diameter (100%).

  As described above, the opening diameter of each nozzle 28 is determined based on the inclination angle θ of the nozzle forming surface with respect to the apparatus bottom surface 48, so that the recording head 2 ′ is attached to the printer 1 ′ regardless of the mounting posture (scheduled mounting angle). Variations in ejection characteristics between the nozzles 28 can be reduced. As a result, it is possible to prevent a deterioration in image quality of an image or the like printed on an ejection target such as recording paper.

  In the above, the ink jet printer 1 which is a kind of liquid ejecting apparatus has been described as an example, but the present invention can also be applied to other liquid ejecting apparatuses. For example, the present invention can be applied to a display manufacturing apparatus for manufacturing a color filter such as a liquid crystal display.

  DESCRIPTION OF SYMBOLS 1 ... Printer, 2 ... Recording head, 15 ... Piezoelectric element, 25 ... Nozzle substrate, 28 ... Nozzle, 40 ... Silicon substrate, 42 ... Mask, 48 ... Bottom of apparatus

Claims (4)

Nozzle group in which a plurality of nozzles are arranged, a plurality of pressure chambers formed corresponding to each nozzle, and a plurality of pressure generations arranged corresponding to each pressure chamber and changing the volume of the pressure chamber A liquid ejecting head that ejects liquid from a corresponding nozzle by driving the pressure generating means to vary the volume of the pressure chamber,
A characteristic measuring step of measuring a displacement amount or a frequency characteristic as a characteristic of each pressure generating means;
A nozzle forming step of forming, on the nozzle substrate, a nozzle having an opening diameter determined based on the characteristics of the corresponding pressure generating means;
A method of manufacturing a liquid ejecting head, comprising: A nozzle group in which a plurality of nozzles are arranged, and
A plurality of pressure chambers formed corresponding to each nozzle;
A plurality of pressure generating means arranged corresponding to each pressure chamber and changing the volume of the pressure chamber;
A liquid ejecting head that ejects liquid from a corresponding nozzle by driving the pressure generating means to vary the volume of the pressure chamber,
An opening diameter of each nozzle is determined based on a displacement amount or frequency characteristic of a corresponding pressure generating means. Nozzle group in which a plurality of nozzles are arranged, a plurality of pressure chambers formed corresponding to each nozzle, and a plurality of pressure generations arranged corresponding to each pressure chamber and changing the volume of the pressure chamber A liquid ejecting head that ejects liquid from a corresponding nozzle by driving the pressure generating means to vary the volume of the pressure chamber,
A liquid ejecting head including a nozzle forming step of forming, on a nozzle substrate, a nozzle having an opening diameter determined based on a predetermined angle of a nozzle forming surface with respect to a bottom surface of the device when the liquid ejecting head is attached to the liquid ejecting apparatus. Manufacturing method. A nozzle group in which a plurality of nozzles are arranged, and
A plurality of pressure chambers formed corresponding to each nozzle;
A plurality of pressure generating means arranged corresponding to each pressure chamber and changing the volume of the pressure chamber;
A liquid ejecting head that ejects liquid from a corresponding nozzle by driving the pressure generating means to vary the volume of the pressure chamber,
An opening diameter of each nozzle is determined based on a predetermined angle of the nozzle forming surface with respect to the bottom surface of the apparatus when the liquid ejecting head is attached to the liquid ejecting apparatus.

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