JP2008012703A - Liquid droplet ejecting head, liquid droplet ejector and manufacturing method for liquid droplet ejecting head - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid droplet ejecting head which is excellent in controllability and uniformity of a shape of the inside periphery of a projecting part in the case of forming the projecting part in the periphery of nozzles for improvement of the reliability of the nozzles, and which is also excellent in removability of foreign substances. <P>SOLUTION: The liquid droplet ejecting head is equipped with both a nozzle plate 2 which has a plurality of the nozzles 2a that eject liquid droplets, and the projection 9 comprised of a plurality of step parts d1 and d2 formed and arranged in the periphery of the nozzles 2a on a surface of the nozzle plate 2 so that an end face of the nozzle 2a side becomes stairlike. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a droplet discharge head, a droplet discharge apparatus, and a method for manufacturing a droplet discharge head. More specifically, the present invention relates to a method of manufacturing a droplet discharge head in the vicinity of a nozzle in order to improve the reliability of the nozzle. The present invention relates to a droplet discharge head, a droplet discharge apparatus, and a method for manufacturing a droplet discharge head that are excellent in shape controllability and uniformity, and also excellent in removal of foreign matters.

Conventionally, in order to improve the reliability of the nozzle formed on the nozzle plate, a structure in which convex portions are provided around the nozzle on the surface of the nozzle plate is used. As such a convex structure, the concave portion is formed in the central portion including the portion where the nozzle of the nozzle plate is formed, so that the peripheral portion is relatively convex, and the foreign matter in the concave portion is improved. A structure in which the inner periphery of the part (the outer periphery of the recess) is formed in a tapered shape is disclosed (for example, see Patent Document 1). This taper makes it easier for the blade performing maintenance around the nozzle on the surface of the nozzle plate to come into contact with the nozzle surface, which is the bottom surface of the recess, and the foreign matter removal capability can be enhanced. In addition, there is a problem that the higher the step forming the convex portion around the nozzle, the greater the remaining amount of ink, and the remaining ink solidifies and reaches the nozzle, affecting the ink ejection. Therefore, there is an advantage that the remaining amount of ink can be reduced by forming the step of the convex portion in a tapered shape. As a method for forming such a taper, for example, electroforming (for example, see Patent Document 2) and laser processing or etching (for example, see Patent Document 3) are disclosed.
Japanese Patent No. 30605526 JP-A-4-234665 JP 2003-276204 A

  However, in the method of forming the taper disclosed in Patent Document 1 and Patent Document 2, it is difficult to control the taper angle of the convex part, and the taper angle uniformity of the plurality of convex parts corresponding to the plurality of nozzles is difficult. There is a problem that it is difficult to ensure.

  The present invention has been made in view of the above-described problems. When a convex portion is provided around the nozzle in order to improve the reliability of the nozzle, the controllability and uniformity of the shape of the inner periphery of the convex portion is excellent. In addition, an object is to provide a droplet discharge head, a droplet discharge device, and a method for manufacturing the droplet discharge head that are excellent in removing foreign matters.

  In order to achieve the above object, one embodiment of the present invention provides the following droplet discharge head, droplet discharge apparatus, and method for manufacturing the droplet discharge head.

[1] A liquid droplet ejection head comprising a nozzle plate having a plurality of nozzles for ejecting liquid droplets, and a protrusion disposed around the nozzle on the surface of the nozzle plate so as to surround the nozzle The liquid droplet ejection head is characterized in that the convex portion is composed of a plurality of step portions formed and arranged so that the end surface on the nozzle side is stepped.

  By comprising in this way, the controllability and uniformity of the shape of the inner periphery of a convex part, and the removal property of a foreign material can be improved.

[2] The plurality of stepped portions are formed so that the size of the opening is the smallest of the first stepped portions formed on the surface of the nozzle plate, and is behind the first stepped portions. The droplet discharge head according to [1], wherein the droplet discharge head is configured to increase in order. By comprising in this way, the controllability and uniformity of the shape of the inner periphery of a convex part can be improved reliably.

[3] The droplet according to [1], wherein the nozzle plate and the first step portion formed on the surface of the nozzle plate are integrally formed of the same material. Discharge head. By comprising in this way, the controllability and uniformity of the shape of the inner periphery of a convex part can be improved simply and reliably.

[4] The droplet according to [3], wherein the nozzle plate and the first step portion formed on the surface of the nozzle plate are made of a first resin material. Discharge head. By comprising in this way, the controllability and uniformity of the shape of the inner periphery of a convex part can be improved simply and reliably.

[5] The droplet according to [1], wherein the nozzle plate and the first step portion formed on the surface of the nozzle plate are separately formed from different materials. Discharge head. By comprising in this way, the freedom degree of the design regarding the shape of a convex part can be expanded.

[6] The droplet according to [5], wherein the nozzle plate is made of a first resin material, and the first step portion is made of a second resin material. Discharge head. By comprising in this way, the freedom degree of design regarding the shape of a convex part can be expanded simply and reliably.

[7] The droplet discharge head according to [1], wherein the plurality of stepped portions are arranged so as to surround the plurality of nozzles together. By configuring in this way, the convex portion can be formed easily and efficiently.

[8] A liquid droplet ejection head including a nozzle plate having a plurality of nozzles for ejecting liquid droplets, and a protrusion disposed around the nozzle on the surface of the nozzle plate so as to surround the nozzle. In the liquid droplet ejection apparatus, the liquid droplet ejection head is characterized in that the convex portion is composed of a plurality of step portions formed and arranged so that the end surface on the nozzle side has a stepped shape. Droplet discharge device.

  With this configuration, a droplet discharge device capable of stable discharge and high-quality printing can be obtained.

[9] A droplet discharge head comprising a nozzle plate having a plurality of nozzles for discharging droplets, and a convex portion disposed around the nozzle on the surface of the nozzle plate so as to surround the nozzle A first step of forming a first step portion on the surface of the nozzle plate so as to have a concave shape surrounding the periphery of the nozzle; and the first step of the nozzle plate A second step of joining a second step plate to the surface of the step portion, and a second step so that the end surface on the nozzle side of the second step plate is stepped. Forming a projection and forming the convex portion constituted by a plurality of the stepped portions, and performing laser processing from the surface of the nozzle plate opposite to the first stepped portion. Forming the nozzle to form the nozzle plate; Fourth step and method for manufacturing a droplet discharge head, characterized in that it comprises a forming a.

  With this configuration, it is possible to easily and efficiently manufacture a droplet discharge head that is excellent in controllability and uniformity of the shape of the inner periphery of the convex portion.

[10] The method further includes a fifth step of forming one or more stepped portions on the surface of the second stepped portion between the third step and the fourth step. The method for manufacturing a droplet discharge head according to [9]. By comprising in this way, the controllability and uniformity of the shape of the inner periphery of a convex part can further be improved.

[11] The plurality of stepped portions are formed such that the size of the opening is the smallest of the first stepped portions formed on the surface of the nozzle plate and is behind the first stepped portions. The method for manufacturing a droplet discharge head according to [9], wherein the droplet discharge heads are configured to increase in order. By comprising in this way, the controllability and uniformity of the shape of the inner periphery of a convex part can be improved smoothly and reliably.

[12] The droplet discharge according to [9], wherein the nozzle plate and the first step portion formed on the surface of the nozzle plate are integrally formed of the same material. Manufacturing method of the head. By comprising in this way, the controllability and uniformity of the shape of the inner periphery of a convex part can be improved simply and reliably.

[13] The liquid droplet ejection head according to [12], wherein the nozzle plate and the first step portion formed on the surface of the nozzle plate are made of a resin material. Method. By comprising in this way, the controllability and uniformity of the shape of the inner periphery of a convex part can be improved simply and reliably.

[14] The method for manufacturing a droplet discharge head according to [9], wherein the plurality of stepped portions are disposed so as to collectively surround the plurality of nozzles. By configuring in this way, the convex portion can be formed easily and efficiently.

[15] A droplet discharge head comprising a nozzle plate having a plurality of nozzles for discharging droplets, and a convex portion disposed around the nozzle on the surface of the nozzle plate so as to surround the nozzle A first step of joining the first step plate to the surface of the nozzle plate, and forming the first step portion so as to surround the periphery of the nozzle A second step, a third step of bonding a second step plate to the surface of the first step, and a stepped end surface on the nozzle side of the second step plate. A fourth step of forming a second stepped portion so as to form a shape, and forming the convex portion composed of a plurality of the stepped portions, and opposite to the first stepped portion of the nozzle plate The nozzle by laser machining from the side surface Fifth step and method for manufacturing a droplet discharge head, characterized in that it comprises a forming the nozzle plate form.

  By configuring in this way, the degree of freedom of design regarding the production of the convex portion can be expanded.

[16] The method further includes a sixth step of forming one or more step portions on the surface of the second step portion between the fourth step and the fifth step. The method for manufacturing a droplet discharge head according to [15]. By comprising in this way, the controllability and uniformity of the shape of the inner periphery of a convex part can further be improved.

[17] The plurality of stepped portions are formed so that the size of the opening is the smallest of the first stepped portions formed on the surface of the nozzle plate, and is behind the first stepped portions. The method for manufacturing a droplet discharge head according to [15], wherein the droplet discharge head is configured to increase in order. By comprising in this way, the controllability and uniformity of the shape of the inner periphery of a convex part can be improved smoothly and reliably.

[18] The droplet discharge according to [15], wherein the nozzle plate and the first stepped portion formed on the surface of the nozzle plate are configured separately from different materials. Manufacturing method of the head. By configuring in this way, the degree of freedom of design regarding the production of the convex portion can be expanded.

[19] The droplet discharge according to [18], wherein the nozzle plate is made of a first resin material, and the first step portion is made of a second resin material. Manufacturing method of the head. By configuring in this way, the degree of freedom of design related to the production of the convex portions can be expanded easily and reliably.

[20] The method for manufacturing a droplet discharge head according to [15], wherein the plurality of stepped portions are disposed so as to collectively surround the plurality of nozzles. By configuring in this way, the convex portion can be formed easily and efficiently.

  According to the present invention, when a convex portion is provided around the nozzle in order to improve the reliability of the nozzle, the droplet discharge is excellent in the controllability and uniformity of the shape of the inner periphery of the convex portion and also in the removal of foreign matters. A head, a droplet discharge device, and a method for manufacturing a droplet discharge head are provided.

[First Embodiment]
(Configuration of droplet discharge head)
1 and 2 show a droplet discharge head according to a first embodiment of the present invention. FIG. 1 is a plan view, FIG. 2A is a cross-sectional view taken along the line AA in FIG. FIG. 2B is a detailed view of a portion B in FIG.

  As shown in FIG. 1, the droplet discharge head 1 includes a substantially parallelogram-shaped diaphragm 7, a plurality of piezoelectric elements 8 disposed on the diaphragm 7, and a position facing the plurality of piezoelectric elements 8. It has a plurality of nozzles 2a formed and by driving the piezoelectric element 8, the liquid stored inside is ejected as droplets from the nozzle 2a. Reference numeral 7 a denotes a supply hole that is provided in the diaphragm 7 and through which liquid is supplied from a liquid tank (not shown) into the head 1.

  Further, as shown in FIG. 2 (a), the droplet discharge head 1 has a nozzle plate 2 on which nozzles 2a are formed, and a flow (on the back side) opposite to the discharge side of the nozzle plate 2 is flowed. As a path member 13, a pool plate 3 having a communication hole 3a and a liquid pool 3b, a supply hole plate 4A having a communication hole 4a and a supply hole 4b, and a supply path plate 5 having a communication hole 5a and a supply path 5b are communicated. A supply hole plate 4B having a hole 4a and a supply hole 4b, a pressure generation chamber plate 6 having a pressure generation chamber 6a, and a vibration plate 7 are sequentially stacked. Further, as described above, a plurality of piezoelectric elements 8 are arranged on the diaphragm 7. A flexible printed wiring board 12 (hereinafter referred to as “FPC12”) for applying a voltage to the piezoelectric elements 8 is disposed so as to cover the plurality of piezoelectric elements 8, and the piezoelectric elements 8 are driven via the FPC 12. Thus, the liquid stored inside is ejected as droplets from the nozzle 2b.

  As shown in FIG. 2B, the droplet discharge head 1 includes a water repellent film 10 comprising a base layer 10a and a water repellent layer 10b on the surface around the nozzle 2a of the nozzle plate 2 and the side surface and surface of the convex portion 9. Is forming. By forming the water repellent film 10 around the nozzle 2a, the liquid droplets discharged from the nozzle 2a are discharged in a direction perpendicular to the nozzle 2a. Further, by providing the convex portion 9 around the nozzle 2a, the water repellent film 10 around the nozzle 2a can be protected from mechanical abrasion due to paper jam or the like. The convex portion 9 has two step portions d1 and d2 that are integrally formed so that the end surface on the nozzle 2a side is stepped.

  1 and 2 show one droplet discharge head 1, a plurality of droplet discharge heads 1 are combined to form a droplet discharge head unit, and a plurality of droplet discharge head units are arranged to form a droplet. It can be used as an ejection head array.

  Next, details of each part of the droplet discharge head 1 will be described.

(Nozzle plate)
The material of the nozzle plate 2 is preferably composed of a synthetic resin from the viewpoint of excellent ink resistance and easy formation of the nozzle 2a. For example, polyimide resin, polyethylene terephthalate resin, liquid crystal polymer And aromatic polyamide resin, polyethylene naphthalate resin, polysulfone resin and the like. Among these, a self-bonding polyimide resin is preferable. The thickness of the nozzle plate 2 is preferably 10 to 100 μm. If it is less than 10 μm, it may be difficult to secure a sufficient nozzle length to achieve good print quality (direction), and if it exceeds 100 μm, the discharge efficiency may be reduced, It may be difficult to ensure flexibility and obtain a sufficient damper effect.

  In the present embodiment, of the two stepped portions d1 and d2 constituting the convex portion 9, the first stepped portion d1 is integrally formed of the same resin material as the nozzle plate 2.

(Convex)
FIG. 3 is a cross-sectional view showing the convex portions of the droplet discharge head according to the first and second embodiments of the present invention. As shown in FIG. 3, the first step portion d1 constituting the convex portion 9 is integrally formed of the same resin material as that of the nozzle plate 2 (may be formed separately from a different material). The second stepped portion d2 formed on the first stepped portion d1 is made of a metal such as SUS from the viewpoint that the etching process described later can be performed smoothly and that the ink resistance is excellent. It is preferable to comprise from. Further, by using a plate made of the same material as the pool plate 3 described later, the etching process can be efficiently performed once. The thickness is preferably 5 to 50 μm.

(Pool plate etc.)
As the material of the pool plate 3 or the like, a metal such as SUS is used from the viewpoints that the etching process can be performed smoothly and that the ink resistance is excellent as in the case of the above-described convex portion 9. preferable.

(Piezoelectric element)
The piezoelectric element 8 is made of, for example, lead zirconate titanate (PZT), and has an individual electrode 8a on the upper surface and a common electrode 8b on the lower surface. The individual electrode 8 a and the common electrode 8 b are formed by sputtering or the like, and the common electrode 8 b on the lower surface is electrically connected to the diaphragm 7 by a conductive adhesive and is grounded via the diaphragm 7. In addition, the piezoelectric element 8 has an area required for discharging at least droplets individually bonded to the position of the diaphragm 7 corresponding to the pressure generating chamber 6a.

(Water repellent film)
As the underlying layer 10a constituting the water-repellent film 10, for example, used with a thickness of 30 to 100 nm, _SiO, the SiO 2, silicon oxide film such as SiO _x, or _Si 2 _N 3, a silicon nitride film such as SiN _x This is preferable because it is excellent in ink resistance and also has excellent adhesion to a resin such as polyimide used for the nozzle plate 2 and a fluorine-based water repellent material used for the water repellent layer 10b. Examples of the water repellent layer 10b include a fluorine water repellent film made of a fluorine compound, a silicone water repellent film, a plasma polymerization protective film, and polytetrafluoroethylene (PTFE) nickel eutectoid plating. . Among these, a fluorine-based water-repellent film made of a fluorine-based compound is preferable because of its excellent water repellency and adhesion. The thickness of the water repellent layer 10b is preferably 50 to 70 nm.

(Liquid flow)
The flow of the liquid will be described with reference to FIG. The liquid supplied to the supply hole 7a of the diaphragm 7 includes the supply hole 6b of the pressure generating chamber plate 6, the supply path 4c of the second supply hole plate 4B, the supply path 5c of the supply path plate 5, and the first supply hole. Plate 4A supply path 4c, pool plate 3 liquid pool 3b, first supply hole plate 4A supply hole 4b, supply path plate 5 supply path 5b, second supply hole plate 4B supply hole 4b, pressure generation The pressure generation chamber 6a of the chamber plate 6, the communication hole 4a of the second supply hole plate 4B, the communication hole 5a of the supply path plate 5, the communication hole 4a of the first supply hole plate 4A, and the communication hole 3a of the pool plate 3 And discharged as droplets from the nozzle 2a of the nozzle plate 2. Thus, the liquid pool 3b is commonly used for supplying the liquid to each nozzle 2a.

(Method for Manufacturing Droplet Discharge Head According to First Embodiment)
5A to 5E are cross-sectional views showing a method of manufacturing the droplet discharge head according to the first embodiment of the present invention in the order of steps.

(1) Joining of plates First, as shown in FIG. 5A, a nozzle plate 2b made of polyimide and a convex plate (SUS) 9a made of SUS are joined.

(2) Formation of Second Stepped Part Next, as shown in FIG. 5 (b), a resist pattern (not shown) is formed on the convex plate (SUS) 9a by photolithography, and this resist pattern As a mask, the convex plate (SUS) 9a is etched to form an opening in the region where the nozzle is formed, thereby forming the second stepped portion d2.

(3) Formation of first step portion (formation of convex portion)
Next, as shown in FIG. 5C, the exposed surface of the opening portion of the convex plate (SUS) 9a is irradiated with an excimer laser so that it is more than the opening of the convex plate (SUS) 9a. A part of the surface of the nozzle plate 2b is removed in a small area to form the first stepped portion d1, and the convex portion 9 composed of the first stepped portion and the second stepped portion as shown in FIG. Form.

(4) Formation of water-repellent film Next, as shown in FIG. 5 (d), the base layer 10a is formed on the surface of the nozzle plate 2b and the surface and side surfaces of the convex plate 9b by, for example, sputtering. Silicon (SiO ₂ ) is deposited, and then a water-repellent layer 10 b made of a fluorine-based water repellent is deposited by vapor deposition to form the water-repellent film 10.

(5) Nozzle processing Next, as shown in FIG. 5 (e), after covering a protective sheet (not shown), laser is applied from the surface opposite to the first step portion d1 of the nozzle plate 2b from the side. By processing, the nozzle 2a is formed and the nozzle plate 2 is formed. The laser used for such laser processing may be a gas laser or a solid laser. Examples of the gas laser include an excimer laser, and examples of the solid laser include a YAG laser. Among these, it is preferable to use an excimer laser.

(6) Joining of Diaphragm and Piezoelectric Element Next, as shown in FIG. 2A, the diaphragm 7 and the plurality of piezoelectric elements 8 are joined on the flow path member 13. As a bonding method, for example, an adhesive such as a thermoplastic resin such as polyimide or polystyrene, or a thermosetting resin such as phenol resin or epoxy resin can be used.

(7) Arrangement of Flexible Printed Circuit Board Next, as shown in FIG. 2A, an FPC 12 for applying a voltage to the piezoelectric elements 8 is arranged so as to cover the plurality of piezoelectric elements 8, and the FPC 12 By driving the piezoelectric element 8 via the nozzle, the liquid stored inside is ejected as droplets from the nozzle 2b. In this way, the droplet discharge head 10 can be obtained.

[Second Embodiment]
(Configuration of droplet discharge head)
The outer shape of the convex portion of the droplet discharge head according to the second embodiment of the present invention is the same as the convex portion of the droplet discharge head according to the first embodiment of the present invention shown in FIG. The material of the convex portion 9 is different from that in the first embodiment. That is, in the case of the first embodiment, as the manufacturing method, as shown in FIG. 5, the second step portion d2 is made of SUS, whereas in the present embodiment, the manufacturing method is Later, as shown in FIG. 6, the second step portion d2 is different from the second polyimide (photosensitive polyimide).

(Manufacturing method of a droplet discharge head according to the second embodiment)
The manufacturing method of the droplet discharge head according to the second embodiment is the same as that in the manufacturing method of the droplet discharge head according to the first embodiment. The droplet discharge head is manufactured by changing the “formation of the step portion” as follows. That is,

(1) Plate Joining FIGS. 6A to 6B are cross-sectional views showing a method of manufacturing a droplet discharge head according to the second embodiment of the present invention in the order of steps. First, as shown in FIG. 6A, the nozzle plate 2b made of the first polyimide and the convex plate (second polyimide) 9b made of the second polyimide (photosensitive polyimide) are joined.

(2) Formation of second step portion Next, as shown in FIG. 6 (b), a convex plate (second polyimide) 9b formed using a predetermined mask 11 is exposed, and then, By developing, an opening is formed in the convex plate (second polyimide) 9b in the region where the nozzle is formed, and the second step portion d2 is formed.

  In the following, in the same manner as in the manufacturing method of the first embodiment, the convex portion 9 including the first step portion d1 and the second step portion d2 as shown in FIG. The discharge head 10 can be obtained.

[Third Embodiment]
FIG. 7 is a cross-sectional view showing a convex portion of a droplet discharge head according to the third embodiment of the present invention. As shown in FIG. 7, the nozzle plate 2 and the first stepped portion d1 formed on the surface of the nozzle plate 2 are configured separately from different materials. In the present embodiment, for example, the nozzle plate 2 is made of the first polyimide, the first step portion is made of the second polyimide, and the second step portion d2 is made of the third polyimide. Each is composed of polyimide.

(Manufacturing method of a droplet discharge head according to the third embodiment)
8A to 8C are cross-sectional views showing a third manufacturing method of the droplet discharge head according to the third embodiment of the present invention in the order of steps.

(1) Joining of plates As shown in FIG. 8A, a nozzle plate 2b made of a first polyimide and a convex plate (third polyimide) 9c made of a third polyimide (photosensitive polyimide) Join.

(2) Formation of first step portion Next, as shown in FIG. 8B, the convex plate (third polyimide) 9c is exposed using a predetermined mask 11a, and then developed. Thus, an opening is formed in the convex plate (third polyimide) 9c in the region where the nozzle is formed, and the first stepped portion d1 is formed.

(3) Formation of second step portion (formation of convex portion 9)
Next, after the convex plate (second polyimide) 9b is bonded onto the convex plate (third polyimide) 9c having the first stepped portion d1, the convex plate using the predetermined mask 11b is used. The plate (second polyimide) 9b is exposed, and then developed to form an opening in the convex plate (second polyimide) 9b in the region where the nozzle is formed, and the second stepped portion d2 is formed. Then, a convex portion 9 including a first step portion d1 and a second step portion d2 as shown in FIG. 7 is formed.

  Thereafter, the droplet discharge head 10 can be finally obtained in the same manner as in the first manufacturing method.

[Fourth Embodiment]
FIG. 9 is a cross-sectional view showing a convex portion of a droplet discharge head according to a fourth embodiment of the present invention. As shown in FIG. 9, in the present embodiment, a third step portion d3 is further formed in the form of the convex portion shown in FIG. 3, and the first step portion d1 to the third step portion d3 are formed. The convex part 9 is formed. The method for forming the third stepped portion d3 can be the same as the method for forming the second stepped portion d2.

  As shown in the first to fourth embodiments, the convex portion 9 has a stepped structure, so that the controllability of the shape is better than that in which the taper angle is formed, and the step portion having a uniform shape. And the removal of foreign matters can be made higher than that of a single stepped portion. Moreover, when forming a level | step-difference part with a metal or resin, since a thin member has high cost or it is difficult to obtain, it is preferable to use a thick member. However, when a thick member is used, since the step portion is high, the remaining area of the ink tends to expand, and the opening must be widened. On the other hand, in the droplet discharge head of the present embodiment, among the plurality of formed step portions, if the step portion around the nozzle 2a is formed thin, there is an advantage that the remaining amount of ink is reduced.

  On the other hand, when the step portion is formed on the plate made of polyimide by laser, it is preferable to process shallowly because the depth of the nozzle 2a is reduced, the throughput is lowered, and the surface is roughened when processed deeply.

  Further, as the planar structure of the convex portion 9, a plurality of stepped portions d1 and d2 may individually surround each nozzle 2a as shown in FIG. 10, or the first step as shown in FIG. The stepped portion d1 may be configured to individually surround each nozzle 2a, and the second stepped portion d2 may include a plurality of nozzles 2a collectively. Further, when a plurality of nozzles 2a are arranged in a row as shown in FIG. 12, the first and second stepped portions d1 and d2 may have a structure surrounding the plurality of nozzles 2a.

  In addition, although the example of the step part of 2 steps | paragraphs was shown above, as shown in FIGS. 13-15, you may form a 3 steps or more step part. 13 shows a structure in which a plurality of step portions d1 to d3 individually surround each nozzle 2a. FIG. 14 shows a structure in which the first and second step portions d1 and d2 individually surround each nozzle 2a. The third stepped portion d3 shows a structure that collectively surrounds the plurality of nozzles 2a, and FIG. 15 shows a structure in which the plurality of stepped portions d1 to d3 collectively surround the plurality of nozzles 2a. In this case, it is preferable to determine the number of nozzles 2a surrounded by each step portion according to the purpose of use of the inkjet head.

[Fifth Embodiment]
(Color printer configuration)
FIG. 16 is a configuration diagram schematically showing a color printer to which a droplet discharge device according to a fifth embodiment of the present invention is applied. This color printer 100 has a substantially box-shaped casing 101, a paper feed tray 20 for storing paper P in the lower part of the casing 101, and a recorded paper P in the upper part of the casing 101. Each of the discharged paper discharge trays 21 is disposed, main conveyance paths 31a to 31e from the paper supply tray 20 via the recording position 102 to the paper discharge tray 21, and from the paper discharge tray 21 side to the recording position 102 side. A transport mechanism 30 that transports the paper P along the reverse transport path 32 is provided.

  At the recording position 102, a plurality of droplet discharge heads 1 shown in FIG. 1 are arranged in parallel to form a recording head unit. The four recording head units are respectively yellow (Y), magenta (M), and cyan (C ) And black (K) recording head units 41Y, 41M, 41C, and 41K that eject ink droplets of each color are arranged in the transport direction of the paper P to form a recording head array.

  Further, the color printer 100 includes a charging roll 43 as an adsorbing unit that adsorbs the paper P, a platen 44 disposed opposite to the recording head unit 20 via the endless belt 35, and recording head units 41Y, 41M, and 41C. The piezoelectric element of the droplet discharge head 1 that controls the maintenance unit 45 arranged in the vicinity of 41K and each part of the color printer 100 and constitutes the recording head units 41Y, 41M, 41C, 41K based on image signals 8 includes a control unit (not shown) that applies a driving voltage to eject ink droplets from the nozzle 2a and records a color image on the paper P.

  The recording head units 41 </ b> Y, 41 </ b> M, 41 </ b> C, and 41 </ b> K have an effective print area that is equal to or larger than the width of the paper P. In addition, although the piezoelectric method was used as a method for discharging droplets, there is no particular limitation, and for example, a widely used method such as a thermal method can be appropriately used.

  Ink tanks 42Y, 42M, 42C, and 42K that store inks corresponding to the recording head units 41Y, 41M, 41C, and 41K are disposed above the recording head units 41Y, 41M, 41C, and 41K. From each ink tank 42Y, 42M, 42C, 42K, it is comprised so that ink may be supplied to each droplet discharge head 1 via piping which is not shown in figure.

  The ink stored in the ink tanks 42Y, 42M, 42C, and 42K is not particularly limited, and for example, commonly used inks such as water-based, oil-based, and solvent-based inks can be appropriately used.

  The transport mechanism 30 is disposed in each part of the pick-up roll 33 that takes out the paper P one by one from the paper feed tray 20 and supplies it to the main transport path 31a, the main transport paths 31a, 31b, 31d, 31e, and the reverse transport path 32. A plurality of transport rolls 34 that transport the paper P, an endless belt 35 that is provided at the recording position 102 and transports the paper P in the direction of the paper discharge tray 21, a drive roll 36 on which the endless belt 35 is stretched, and a follower A roll 37 and a drive motor (not shown) that drives the transport roll 34 and the drive roll 36 are provided.

(Color printer operation)
Next, the operation of the color printer 100 will be described. The transport mechanism 30 drives the pickup roll 33 and the transport roll 34 under the control of the control unit, takes out the paper P from the paper feed tray 20, and transports it along the main transport paths 31a and 31b. When the paper P reaches the vicinity of the endless belt 35, electric charge is applied to the paper P by the electrostatic attraction force of the charging roll 43, and the paper P is attracted to the endless belt 35.

  The endless belt 35 is rotated by driving of the driving roll 36, and when the paper P is conveyed to the recording position 102, a color image is recorded by the recording head units 41Y, 41M, 41C, and 41K.

  That is, the liquid pool 3b of the droplet discharge head 1 shown in FIG. 16 is filled with ink supplied from the ink tanks 42Y, 42M, 42C, and 42K, and ink is supplied from the liquid pool 3b to the supply holes 4b and the supply paths 5b. Is supplied to the pressure generating chamber 6a, and ink is stored in the pressure generating chamber 6a. When the control unit selectively applies a drive voltage to the plurality of piezoelectric elements 8 based on the image signal, the vibration plate 13 bends as the piezoelectric elements 8 are deformed, thereby changing the volume in the pressure generating chamber 6a. Then, the ink stored in the pressure generating chamber 6a is ejected as ink droplets from the nozzle 2a onto the paper P through the communication holes 5a, 4a, 3a, and an image is recorded on the paper P. On the paper P, Y, M, C, and K images are sequentially overwritten, and a color image is recorded. In this case, since the damper portion 11 is formed on the nozzle plate 2, stable discharge and high-quality printing can be realized easily and inexpensively by absorbing fluctuations in the discharge amount of the droplets.

  The paper P on which the color image is recorded is discharged to the paper discharge tray 21 by the transport mechanism 30 via the main transport path 31d.

  When the duplex recording mode is set, the paper P once discharged to the paper discharge tray 21 returns to the main transport path 31e again, passes through the reverse transport path 32, and again passes through the main transport path 31b. Then, the color image is recorded on the surface opposite to the surface of the paper P recorded last time by the recording head units 41Y, 41M, 41C, and 41K.

  The present invention is not limited to the above embodiments, and various modifications can be made without departing from the spirit of the invention. For example, all the stepped portions formed on the surface of the nozzle plate 2, for example, the first to third stepped portions d1 to d3 may be integrally formed with the nozzle plate 2 from the same material as the nozzle plate 2. In addition, the second step portion d2 and the third step portion d3 may be integrally formed from the same material.

  The droplet discharge head, the droplet discharge apparatus, and the manufacturing method of the droplet discharge head according to the present invention are various industrial fields in which a high-definition image information pattern is required to be formed by discharging droplets, for example, Ink is ejected onto a polymer film or glass surface using an ink jet method to form a color filter for display, or a solder paste is ejected onto a substrate to form component mounting bumps. It is effectively used in the electrical / electronic industry fields, such as forming wiring, and in the medical field, which manufactures biochips that test reaction with a sample by discharging a reaction reagent onto a glass substrate or the like.

1 is a plan view of a droplet discharge head according to a first embodiment of the present invention. (A) is the sectional view on the AA line of FIG. 1, (b) is the B section detailed drawing of (a). It is sectional drawing which shows the convex part of the droplet discharge head which concerns on the 1st and 2nd embodiment of this invention. It is a disassembled perspective view of the droplet discharge head shown in FIG. (A)-(e) is sectional drawing which shows the manufacturing method of the droplet discharge head which concerns on the 1st Embodiment of this invention in order of a process. (A), (b) is sectional drawing which shows the manufacturing method of the droplet discharge head concerning the 2nd Embodiment of this invention in order of a process. It is sectional drawing which shows the convex part of the droplet discharge head which concerns on the 3rd Embodiment of this invention. (A)-(c) is sectional drawing which shows the manufacturing method of the droplet discharge head which concerns on the 3rd Embodiment of this invention in order of a process. It is sectional drawing which shows the convex part of the droplet discharge head which concerns on the 4th Embodiment of this invention. An example of the planar structure of the convex part of the droplet discharge head concerning an embodiment of the invention is shown, (a) is a top view and (b) is a CC line sectional view of (a). An example of the planar structure of the convex part of the droplet discharge head concerning an embodiment of the invention is shown, (a) is a top view, (b) is a DD line sectional view of (a), ( (c) is the EE sectional view taken on the line of (a). An example of the planar structure of the convex part of the droplet discharge head concerning an embodiment of the invention is shown, (a) is a top view, (b) is a FF line sectional view of (a), ( FIG. 11C is a sectional view taken along line GG in FIG. An example of the planar structure of the convex part of the droplet discharge head concerning an embodiment of the invention is shown, (a) is a top view and (b) is a HH line sectional view of (a). An example of the planar structure of the convex part of the droplet discharge head which concerns on embodiment of this invention is shown, (a) is a top view, (b) is the II sectional view taken on the line of (a), ( (c) is the JJ sectional view taken on the line of (a). An example of the planar structure of the convex part of the droplet discharge head concerning an embodiment of the invention is shown, (a) is a top view, (b) is a KK line sectional view of (a), ( c) is a sectional view taken along line LL in FIG. It is a block diagram which shows typically the color printer to which the droplet discharge apparatus which concerns on the 5th Embodiment of this invention is applied.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Droplet discharge head 2 Nozzle plate 2a Nozzle 2b Nozzle plate 3 Pool plate 3a Communication hole 3b Liquid pool 4 Supply hole plate 4a Communication hole 4b Supply hole 5 Supply path plate 5a Communication hole 5b Supply path 6 Pressure generating chamber plate 6a Pressure Generation chamber 7 Vibration plate 7a Supply hole 8 Piezoelectric element 9 Convex part 9a Convex part plate (SUS)
9b Plate for convex part (second polyimide)
9c Plate for convex part (third polyimide)
DESCRIPTION OF SYMBOLS 10 Water repellent film 10a Underlayer 10b Water repellent layer 11 Mask 11a Mask 12 Flexible wiring board (FPC)
13 Channel member 20 Paper feed tray 21 Paper discharge tray 30 Transport mechanisms 31a to 31e Main transport path 32 Reverse transport path 33 Pickup roll 34 Transport roll 35 Endless belt 36 Drive roll 37 Driven rolls 41Y, 41M, 41C, 41K Recording head unit 42Y, 42M, 42C, 42K Ink tank 43 Charging roll 44 Platen 45 Maintenance unit 100 Color printer 101 Housing 102 Recording position d1 First stepped portion d2 Second stepped portion d3 Third stepped portion P Paper

Claims (20)

A droplet discharge head comprising: a nozzle plate having a plurality of nozzles for discharging droplets; and a protrusion disposed around the nozzle on the surface of the nozzle plate so as to surround the nozzle. ,
The liquid droplet ejection head, wherein the convex portion is composed of a plurality of step portions formed and arranged so that the end surface on the nozzle side has a stepped shape.   The plurality of stepped portions have openings whose size is such that the first stepped portion formed on the surface of the nozzle plate is the smallest and formed after the first stepped portion. The droplet discharge head according to claim 1, wherein the droplet discharge head is configured to be large.   The droplet discharge head according to claim 1, wherein the nozzle plate and the first step portion formed on the surface of the nozzle plate are integrally formed of the same material.   The droplet discharge head according to claim 3, wherein the nozzle plate and the first step portion formed on the surface of the nozzle plate are made of a first resin material.   2. The droplet discharge head according to claim 1, wherein the nozzle plate and the first step portion formed on the surface of the nozzle plate are separately formed from different materials.   6. The liquid droplet ejection head according to claim 5, wherein the nozzle plate is made of a first resin material, and the first step portion is made of a second resin material.   2. The droplet discharge head according to claim 1, wherein the plurality of stepped portions are disposed so as to collectively surround the plurality of nozzles. A liquid having a droplet discharge head including a nozzle plate having a plurality of nozzles for discharging droplets, and a convex portion disposed around the nozzle on the surface of the nozzle plate so as to surround the nozzle In the droplet ejection device,
In the droplet discharge head, the convex portion is composed of a plurality of step portions formed and arranged so that an end surface on the nozzle side is stepped. A droplet discharge head is manufactured that includes a nozzle plate having a plurality of nozzles for discharging droplets, and a protrusion disposed around the nozzle on the surface of the nozzle plate so as to surround the nozzle. A method,
A first step of forming a first step portion on the surface of the nozzle plate so as to have a concave shape surrounding the periphery of the nozzle;
A second step of joining a second step plate to the surface of the first step portion of the nozzle plate;
A second step portion is formed on the second step portion plate so that an end surface on the nozzle side has a stepped shape, and a third protrusion is formed from the plurality of step portions. And the process of
And a fourth step of forming the nozzle plate by laser processing from a surface opposite to the first step portion of the nozzle plate to form the nozzle plate. Manufacturing method of the discharge head.   The method further comprises a fifth step of forming one or more step portions on the surface of the second step portion between the third step and the fourth step. 10. A method for manufacturing a droplet discharge head according to item 9.   The plurality of stepped portions have openings whose size is such that the first stepped portion formed on the surface of the nozzle plate is the smallest and formed after the first stepped portion. The method for manufacturing a droplet discharge head according to claim 9, wherein the droplet discharge head is configured to be large.   The method for manufacturing a droplet discharge head according to claim 9, wherein the nozzle plate and the first step portion formed on the surface of the nozzle plate are integrally formed of the same material. .   13. The method of manufacturing a droplet discharge head according to claim 12, wherein the nozzle plate and the first step portion formed on the surface of the nozzle plate are made of a resin material.   The method for manufacturing a droplet discharge head according to claim 9, wherein the plurality of stepped portions are arranged so as to surround the plurality of nozzles together. A droplet discharge head is manufactured that includes a nozzle plate having a plurality of nozzles for discharging droplets, and a protrusion disposed around the nozzle on the surface of the nozzle plate so as to surround the nozzle. A method,
A first step of joining the first step plate to the surface of the nozzle plate;
A second step of forming a first stepped portion so as to have a shape surrounding the periphery of the nozzle;
A third step of bonding a second step plate to the surface of the first step,
A second step portion is formed on the second step portion plate so that an end surface on the nozzle side has a stepped shape, and the convex portion constituted by a plurality of the step portions is formed. And the process of
And a fifth step of forming the nozzle plate by performing laser processing from a surface opposite to the first step portion of the nozzle plate to form the nozzle plate. Manufacturing method of the discharge head.   The method further comprises a sixth step of forming one or more stepped portions on the surface of the second stepped portion between the fourth step and the fifth step. 15. A method for manufacturing a droplet discharge head according to 15.   The plurality of stepped portions have openings whose size is such that the first stepped portion formed on the surface of the nozzle plate is the smallest and formed after the first stepped portion. The method for manufacturing a droplet discharge head according to claim 15, wherein the droplet discharge head is configured to be large.   The method of manufacturing a droplet discharge head according to claim 15, wherein the nozzle plate and the first step portion formed on the surface of the nozzle plate are separately formed from different materials. .   19. The method for manufacturing a droplet discharge head according to claim 18, wherein the nozzle plate is made of a first resin material, and the first step portion is made of a second resin material. .   The method of manufacturing a droplet discharge head according to claim 15, wherein the plurality of stepped portions are disposed so as to collectively surround the plurality of nozzles.

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