JP5737973B2 - Ink jet recording head and manufacturing method thereof - Google Patents

Description

  The present invention relates to an ink jet recording head that performs recording by discharging ink and a method for manufacturing the same.

  FIG. 1 is a schematic configuration diagram partially showing a general ink jet recording head. FIG. 1A is a perspective view partially showing a vertical cross section, and FIG. 1B is a vertical cross sectional view showing an enlarged area A surrounded by a two-dot chain line in FIG. .

  The ink jet recording head shown in FIG. 1 is configured such that ink supplied from an ink tank (not shown) to the supply port 120 is discharged from the discharge port 133 through the flow path 134.

  The supply port 120 is formed in the substrate 111 and includes two parts, a common port 121 and a communication port 122. The common port 121 is formed so that the width decreases from the surface of the substrate 111 opposite to the flow path 134 side toward the flow path 134.

  The communication port 122 is a passage that allows the common port 121 and the flow path 134 to communicate with each other. A plurality of communication ports 122 are formed perpendicular to the surface of the substrate 111. Patent Document 1 discloses an ink jet recording head provided with a supply port formed perpendicular to a substrate in the same manner as the communication port 122 shown in FIG.

  The flow path 134 shown in FIG. 1 is surrounded by an orifice portion 131 and a flow path wall 132 formed on the surface of the substrate 111. The orifice part 131 is formed of a plate provided with a plurality of discharge ports 133. Discharge pressure generating elements 112 are provided at positions on the surface of the substrate 111 facing the discharge ports 133.

  The discharge pressure generating element 112 applies pressure to the ink in the flow path 134 and discharges the ink from the discharge port 133. A passivation layer 113 that protects the ejection pressure generating element 112 from ink is provided on the flow path side surface of the substrate 111.

  In such an ink jet recording head, an operation of replenishing ink from the supply port 120 into the flow channel 134 (hereinafter referred to as “refill”) in association with a discharge operation of discharging the ink in the flow channel 134 from the discharge port 133. Is done. In order to perform accurate refilling, the communication port 122 is provided in the vicinity of each discharge port 133.

  As described above, there are spaces such as the supply port 120, the flow path 134, and the discharge port 133 in the inkjet recording head. If there are foreign objects in these spaces in the ink jet recording head, the ink flow may be hindered by the foreign objects. In such a case, the ink may be denatured due to the reaction between the ink and the foreign matter.

  For this reason, the ink jet recording head may not be able to normally perform the ejection operation and refill.

  Therefore, in the manufacturing process of the ink jet recording head, generally, cleaning for removing foreign matters in the space in the ink jet recording head is performed. As a method for cleaning a space in an ink jet recording head, a method using a fluid such as liquid or gas is known.

  As a cleaning method using a liquid such as a cleaning liquid, there is a method in which an ink jet recording head is swung and a bubble is sprayed in a liquid tank containing the liquid. In some cases, a shower-like liquid is sprayed directly onto the ink jet recording head.

  Further, there is a cleaning method in which both a gas and a liquid are simultaneously sprayed onto the ink jet recording head. Such a cleaning method is called two-fluid cleaning.

  In any of the cleaning methods described above, fluid flows into the space in the ink jet recording head from the supply port 120 and the discharge port 133 shown in FIG. 1 and flows out of the supply port and the discharge port from the space. It is common to repeat.

  By such a fluid flow, force is applied from the fluid to the foreign matter adhering to the wall surface of the space in the ink jet recording head, and the foreign matter in the space in the ink jet recording head is removed to the outside of the ink jet recording head.

US Pat. No. 6,555,480

  When the ink jet recording head shown in FIG. 1 is washed, the fluid that has flowed from the discharge port 133 enters the flow path 134 as indicated by the broken line arrow in FIG. Thereafter, the fluid in the flow path 134 tends to flow in a direction along the surfaces of the substrate 111 and the orifice portion 131 in accordance with the law of inertia.

  On the other hand, the communication port 122 of the supply port 120 is formed perpendicular to the surface of the substrate 111. Since the traveling direction of the fluid in the flow path 134 does not change suddenly, the fluid does not smoothly flow into the supply port 120 from the flow path 134. For example, the fluid that has entered the flow path 134 from the discharge port 133 may pass through the nearest communication portion 122 along the flow path 134.

  For this reason, the flow of fluid at the supply port 120, particularly the communication port 122 on the flow path 134 side, may be partially gradual. Therefore, there is a case where the force applied from the fluid to the wall surface of the communication port 122 is not sufficiently obtained, and the communication port 122 cannot be sufficiently cleaned.

  Moreover, when it is necessary to form many communication ports 122 with respect to one common port 121, the total area of the wall surface of the communication port 122 to which a foreign material can adhere becomes large. For this reason, it is difficult to remove all foreign matters from the communication port 122.

  Further, when the communication port 122 is formed to be elongated in a direction perpendicular to the surface of the substrate 11, it is difficult for fluid to enter the communication port 122. Therefore, also in this case, it becomes difficult to clean the communication port 122.

  In addition, it is generally difficult to form a hole perpendicular to the surface of the substrate 111 such as the communication port 122 shown in FIG. 1, and as described in FIG. Often becomes.

  As an effective method for forming the communication port 122, there is a Bosch process in which etching and wall surface protection are repeatedly performed. However, the wall surface of the communication port formed by using the Bosch process also has a periodic uneven shape called a scallop shape.

  Thus, it is difficult to form the wall surface of the communication port 122 formed perpendicular to the surface of the substrate 111 smoothly. Foreign matter tends to adhere to the wall surface of the communication port 122 that is not smooth. Moreover, the foreign material adhering to the wall surface of the communication port 122 which is not smooth is hard to be removed.

  Accordingly, an object of the present invention is to provide an ink jet recording head capable of effectively cleaning the supply port.

To achieve the above object, an ink jet recording head includes a substrate supply port is formed, and an orifice portion discharge opening is formed, but is disposed to face the liquid supplied from the supply port and said substrate an inkjet recording head ejected from the discharge port through the flow path between the orifice portion, the supply port has a wall surface of the scallops which intersects before Symbol passage side, of the orifice portion , and having the projecting position opposite to whether we before Symbol flow path to the supply port, the farther from the orifice section narrowing tapered columnar portion.

  According to the present invention, it is possible to provide an ink jet recording head capable of effectively cleaning the supply port and a manufacturing method thereof.

It is a schematic block diagram of a general inkjet recording head. 1 is a schematic configuration diagram illustrating an inkjet recording head according to an embodiment of the present invention. FIG. 3 is a schematic configuration diagram illustrating a modified example of the ink jet recording head illustrated in FIG. 2. FIG. 3 is a cross-sectional view showing a manufacturing process of the ink jet recording head shown in FIG. 2. FIG. 3 is a cross-sectional view showing a manufacturing process of the ink jet recording head shown in FIG. 2. FIG. 3 is a cross-sectional view showing a manufacturing process of the ink jet recording head shown in FIG. 2. FIG. 6 is a cross-sectional view illustrating a modification of the ink jet recording head illustrated in FIG. 2.

Next, embodiments of the present invention will be described with reference to the drawings.
(First embodiment)
FIG. 2 is a schematic configuration diagram partially showing the ink jet recording head 1 according to the first embodiment of the present invention. FIG. 2A is a partial perspective view showing a part in a longitudinal section. FIG. 2B is an enlarged cross-sectional view taken along the line XX ′ showing the region B surrounded by the two-dot chain line in FIG. FIG. 2 (c) is an enlarged longitudinal sectional view showing a region B surrounded by a two-dot chain line in FIG. 2 (a).

  The ink jet recording head 1 according to this embodiment is configured such that ink supplied from an ink tank (not shown) to the supply port 20 is discharged from the discharge port 33 through the flow path 34.

  The ink jet recording head 1 includes a substrate 11 on which a supply port 20 penetrating in the thickness direction is formed. The supply port 20 includes two parts, a common port 21 and a communication port 22.

  The common port 21 is formed so that the width is narrowed toward the flow path 34 from the surface of the substrate 11 opposite to the flow path 34 side. The communication port 22 is a passage that allows the common port 21 and the flow path 34 to communicate with each other. A plurality of communication ports 22 are formed perpendicular to the surface of the substrate 11.

  In general, it is difficult to form the communication port 22 that is exactly perpendicular to the surface of the substrate 11. For this reason, the vertical state includes a state that is not exactly a vertical state but can be regarded as substantially vertical.

  In FIG. 2B, the position where the wall surface of the communication port 22 shown in FIG. 2A is projected onto the surface along the X-X ′ line is indicated by a broken line. Here, a region surrounded by a broken line is referred to as a “cross section of the communication port 22”.

  The flow path 34 shown in FIG. 2 is surrounded by an orifice portion 31 and a flow path wall 32 formed on the communication port 22 side of the substrate 11. The orifice portion 31 and the flow path wall 32 are formed of a resin material.

  The orifice portion 31 has a plate shape parallel to the surface of the substrate 11. The flow path wall 32 partially connects the orifice portion 31 and the substrate 11. In this embodiment, the orifice part 31 is formed integrally with the flow path wall 32, but the orifice part may be formed separately from the flow path wall as a single plate (orifice plate).

  The orifice portion 31 is provided with a plurality of discharge ports 33 penetrating in the thickness direction. Discharge pressure generating elements 12 are provided on the surface of the substrate 11 at positions facing the respective discharge ports 33.

  The discharge pressure generating element 12 applies pressure to the ink in the flow path 34 and discharges the ink from the discharge port 33. The ink jet recording head 1 according to the present embodiment is a thermal type, and a heater is used as the discharge pressure generating element 12. However, the discharge pressure generating element 12 may be any element that can apply pressure to the ink in the flow path 34.

  A passivation layer 13 for protecting the ejection pressure generating element 12 from ink is provided on the surface of the substrate 11. The gap between the passivation layer 13 and the orifice part 31, that is, the height of the flow path 34 is appropriately determined between 3 μm and 30 μm.

  The communication port 22 is a space surrounded by four wall surfaces perpendicular to the surface of the substrate 11. The length of each side of the cross section of the communication port 22 is appropriately determined between 10 μm and 200 μm. In the present embodiment, the shape of the cross section of the communication port 22 is a square. However, the shape of the cross section of the communication port 22 can be determined as appropriate, and may be, for example, a rectangle or a circle.

  The shortest distance L between the discharge port 33 and the communication port 22 is 20 μm to 200 μm when the discharge port 33 and the communication port 22 are projected onto the plane along the line XX ′ shown in FIG. As appropriate. The length of the distance L is determined according to the refill characteristics, for example. The shorter the distance L, the faster the refill is possible.

  The ink jet recording head 1 according to this embodiment has a columnar portion 41. The columnar part 41 protrudes in a direction perpendicular to the orifice part 31 from a position facing the communication port 22 of the orifice part 31. That is, the columnar part 41 extends toward the communication port 22.

  The columnar portion 41 extends to a surface that coincides with the surface of the passivation layer 13. That is, the height of the columnar portion 41 is appropriately determined between 3 μm and 30 μm according to the height of the flow path 34. The columnar portion 41 has a quadrangular columnar shape, and the four corners in the cross section are chamfered as shown in FIG.

  Further, as shown by a dotted line in FIG. 2B, the intersection of the diagonal lines of the columnar body 41 is equal to the intersection of the diagonal lines of the communication port 22. Here, a line orthogonal to the surface of the substrate 11 and passing through the intersection of the diagonal lines of the columnar body 41 and the communication port 22 is referred to as the central axis of the columnar body 41 and the communication port 22. That is, the central axis of the columnar body 41 and the central axis of the communication port 22 are common.

  The area of the cross section of the columnar body 41 can be appropriately determined based on the area of the cross section of the communication port 22. The area of the cross section of the columnar body 41 can be appropriately determined between 10% and 70% of the area of the cross section of the communication port 22, for example.

  In the inkjet recording head 1 according to the present embodiment, the fluid that flows in from the discharge port 33 and flows in the flow path 34 in parallel with the surface of the substrate 11 during the cleaning process in the manufacturing process is routed by the columnar portion 41. Is disturbed. Therefore, the traveling direction of the fluid in the flow path 34 is forcibly changed by the columnar portion 41.

  As indicated by broken line arrows in FIGS. 2B and 2C, the fluid whose traveling direction has been changed by the columnar portion 41 flows in various directions. In particular, as shown in FIG. 2C, the fluid whose traveling direction has been changed to the columnar body 41 is smoothly guided into the communication port 22.

  Thus, by providing the columnar body 41, a sufficient amount of fluid flows from the flow path 34 into the communication port 22. Therefore, in the inkjet recording head 1 according to the present embodiment, a sufficient force is applied from the fluid to the wall surface of the communication port 22, so that the inside of the communication port 22 of the supply port 20 can be effectively cleaned.

  The supply port of the ink jet recording head may not have the communication port 22 on the flow path 34 side formed perpendicular to the surface of the substrate 11 as in the present embodiment. Furthermore, the supply port may not be configured by the common port 21 and the communication port 22 as in the present embodiment.

  If the supply port of the ink jet recording head is surrounded by the wall surface intersecting the flow path 34, the fluid flowing through the flow path 34 can be smoothly caused to flow into the supply port by the action of the columnar body 41. it can. Therefore, the cleaning effect of the supply port by the columnar body 41 is effective for any supply port having such a configuration.

  With reference to FIG. 3, the modification of the columnar part 41 which concerns on this embodiment is demonstrated. Each figure in FIG. 3 is a cross-sectional view corresponding to FIG.

  The columnar portion 41a shown in FIG. 3A has a square cross-sectional shape. Each side of the cross section of the communication port 22 is parallel to each side of the cross section of the columnar portion 41a. Accordingly, the distances l between the four sides of the cross section of the columnar part 41a and the four sides of the communication port 22 corresponding to each side are all equal. With this configuration, the fluid uniformly hits any wall surface of the communication port 22. Thereby, the cleaning effect of the communication port 22 is made uniform.

  In the columnar portion 41 b shown in FIG. 3B, the four sides of the cross section are inclined with respect to the four sides of the cross section of the communication port 22. Further, the columnar portion 41c shown in FIG. 3C has a circular cross section. In addition, the shape of the cross section of the columnar part can be determined as appropriate.

  The columnar portion 41d shown in FIG. 3D is formed by dividing the columnar portion into four. In the configuration shown in FIG. 3E, a columnar portion 41f is arranged at the center, and four columnar portions 41e are provided around the columnar portion 41f. The columnar part 41f and the columnar part 41e have different cross-sectional areas and different numbers.

  As shown in FIGS. 3D and 3E, when providing a plurality of columnar portions, it is desirable to dispose the columnar portions at the corners of the communication port 22. Although the fluid is difficult to reach the corner of the communication port 22 particularly during the cleaning process, the corner of the communication port 22 can be effectively cleaned by this configuration.

  As mentioned above, although the columnar part of this embodiment was illustrated, arrangement | positioning, a shape, a quantity, etc. of a columnar part can be determined suitably.

  Next, a method for manufacturing the ink jet recording head 1 according to the present embodiment will be described with reference to FIGS. 4, 5, and 6.

  First, as shown in FIG. 4A, a substrate 11 is prepared on which a plurality of discharge pressure generating elements 12 are arranged on the surface and a passivation layer 13 for protecting the discharge pressure generating elements 12 is formed.

  Next, as shown in FIG. 4B, the positive resist 51 is patterned. In the patterning of the positive resist 51, each process of coating a resin mainly composed of polymethylisopropenyl ketone on the surface of the substrate 11, exposing to UV (UltraViolet) light with a proxy type exposure machine, and developing with xylene is sequentially performed. Apply.

  The positive resist 51 is later eluted and patterned into a portion that becomes the flow path 34 shown in FIG. Therefore, instead of the positive resist 51, another material that can be eluted may be patterned.

  Next, as shown in FIG. 4C, the epoxy resin 52 is patterned so as to cover the positive resist 51. In the present embodiment, a cationic polymerization type epoxy resin 52 is used.

  Next, as shown in FIG. 4D, the discharge port 33 is formed by exposing and developing the epoxy resin 52. The epoxy resin 52 shown in FIG. 4C constitutes the orifice part 31, the flow path wall 32, and the columnar part 41 as a unit as shown in FIG. 4D.

  Subsequent to the process shown in FIG. 4, the process shown in FIG. 5 is performed. Although FIG. 4 shows the discharge port 33 facing upward, FIG. 5 shows the discharge port 33 facing downward for convenience of explanation.

  First, as shown in FIG. 5A, the mask material 54 is patterned on the surface of the substrate 11 opposite to the orifice portion 31 where the supply port 20 shown in FIG. 2 is not formed. Then, the solvent coat 53 is patterned so as to cover the orifice portion 31 and the flow path wall 32 on the surface of the substrate 11. The solvent coat 53 is formed of cyclized rubber and protects the orifice portion 31 and the flow path wall 32.

  Next, as shown in FIG. 5B, crystal anisotropic etching is performed on the surface of the substrate 11 that is not covered with the mask material 54 to form the common port 21. Then, a positive resist (not shown) is applied to the common port 21 by a spray method.

  Next, as shown in FIG. 5C, the substrate 11 is dug by a Bosch process, and the communication port 22 is formed up to the passivation layer 13. And the part corresponding to the communicating port 22 of the passivation layer 13 is removed by CDE (Chemical Dry Etching) method. For forming the communication port 22, a method using high-density plasma may be used instead of the Bosch process.

  Next, as shown in FIG. 5D, the solvent coat 53 is removed with xylene. Then, the positive resist 51 is exposed by irradiating UV light from the discharge port 33 side of the substrate 11. At this time, the UV light passes through the orifice portion 31 and the entire positive resist 51 is exposed. Then, the exposed positive resist 51 is removed using methyl lactate, and the flow path 34 is formed.

  And it is made to rock | fluctuate in a pure water tank, and a washing | cleaning process is performed by providing a bubble. At this time, as indicated by broken line arrows in FIG. 5D, the pure water that has flowed into the flow path 34 from the discharge port 33 is changed in the flow direction by the columnar body 41 and flows into the communication port 22. Therefore, a sufficient amount of pure water flows into the communication port 22 and a sufficient force is applied to the wall surface of the communication port 22. Thereby, the foreign matter adhering to the wall surface of the communication port 22 is removed to the outside of the ink jet recording head.

  Subsequent to the process shown in FIG. 5, the process shown in FIG. 6 is performed. In FIG. 6, the discharge port 33 is shown to face upward as in FIG.

  In the manufacturing process shown in FIGS. 4 and 5, the plurality of inkjet recording heads 1 shown in FIG. 2 are connected to each lot of the substrate 11. Therefore, the process shown in FIG. 6 for cutting the substrate 11 is required for each inkjet recording head 1.

  The ink jet recording head 1 is cut by a dicing device (not shown). As a preparatory process for that purpose, an ink jet recording head in a state where the substrate 11 is connected to each substrate for each lot is attached to the base material 60 shown in FIG. As the base material 60, for example, a UV tape can be used. At this time, the surface of the substrate 11 opposite to the discharge port 33 is an adhesive surface for the base material 60.

  Thereafter, as shown in FIG. 6A, the substrate 60 is fixed, and each ink jet recording head 1 is cut by a dicing saw 61 provided in the dicing apparatus. At that time, a water-cooling nozzle provided in the dicing apparatus is provided at a contact portion of the dicing saw 61 with the substrate 11 for the purpose of cooling the heat generated by the friction between the dicing saw 61 and the substrate 11 and removing chips of the substrate 11. Spray water with 63. A spacing 62 corresponding to the thickness of the dicing saw 61 is formed between the inkjet recording heads 1 as shown in FIG.

  Next, as shown in FIG. 6B, the separated ink jet recording head 1 is cleaned by spraying a cleaning liquid by the cleaning device 64. At that time, as shown in FIG. 6C, the cleaning liquid flows not only in the space in each inkjet recording head 1 but also in the spacing 62. Thereby, the chip | tip of the board | substrate 11 produced by dicing is removed.

  Finally, each inkjet recording head 1 is peeled off from the base material 60, and the inkjet recording head 1 is completed.

In the ink jet recording head 1 according to the present embodiment, when the ink jet recording head 1 is used after being attached to the recording apparatus, the cleaning before refilling (refilling) the ink is performed effectively in the same manner. Can do.
(Second Embodiment)
FIG. 7 is a schematic configuration diagram partially showing a second embodiment of the present invention. Each drawing in FIG. 7 is a longitudinal sectional view corresponding to FIG. The inkjet recording head according to the present embodiment is the same as the configuration of the inkjet recording head 1 according to the first embodiment except for the configuration described below. In FIG. 7, configurations common to the inkjet recording head 1 according to the first embodiment are denoted by the same reference numerals.

In the ink jet recording head according to this embodiment, a functional layer 14 and an insulating layer 15 are provided between the ejection pressure generating element 12 and the substrate 11. The functional layer 14 includes an electric circuit for driving the discharge pressure generating element 12 and the like. The insulating layer 15 electrically insulates the functional layer 14 from other components such as the discharge pressure generating element 12 while ensuring necessary electrical connection.

  In any of the inkjet recording heads shown in FIG. 7, the functional layer 14 is provided around the communication port 20, and the passivation layer 13 corresponding to the portion swells in the flow path 34.

  In the ink jet recording head shown in FIG. 7A, a square columnar portion 41g similar to that in FIG. 2 extends to a surface including the surface of the insulating layer 15 on which the ejection pressure generating element 12 is provided. In this ink jet recording head, even if the functional layer 15 is provided, effective cleaning can be performed as in the ink jet recording head 1 according to the first embodiment.

  In the ink jet recording head shown in FIG. 7B, the tapered columnar portion 41 h that becomes thinner as it gets away from the orifice portion 31 extends to the surface including the surface of the insulating layer 15 provided with the ejection pressure generating element 12. ing. That is, the tapered surface of the columnar part 41h faces the communication port 22 side. In this ink jet recording head, the traveling direction of the fluid colliding with the tapered columnar portion 41h can be changed more smoothly toward the communication port 22 during the cleaning process. Thereby, the inside of the communication port 22 can be cleaned more effectively.

  Further, in the ink jet recording head shown in FIG. 7C, a square columnar portion 41 i similar to that in FIG. 2 extends into the communication port 22. In this ink jet recording head, the columnar body 41i is long, and the traveling direction of more fluid is changed by the columnar body 41i during the cleaning process. Thereby, the inside of the communication port 22 can be cleaned more effectively.

DESCRIPTION OF SYMBOLS 11 Board | substrate 12 Discharge pressure generating element 13 Passivation layer 20 Supply port 21 Common port 22 Communication port 31 Orifice part 32 Channel wall 33 Discharge port 34 Channel 41 Columnar part

Claims (7)

A substrate supply port is formed, and an orifice portion discharge opening is formed, but is disposed to face the liquid supplied from the supply port through the flow path between the substrate and the orifice portion An inkjet recording head ejected from the ejection port,
The supply port has a wall surface of the scallops which intersects before Kiryuro,
Wherein the orifice portion, the projecting position opposite to whether we before Symbol flow path to the supply port, the ink jet recording head which comprises said increasing distance from the orifice section narrowing tapered columnar portion. The ink jet recording head according to claim 1, wherein the columnar portion enters the supply port. The supply port includes a common port formed on the side opposite to the flow channel side, and the common port and the flow channel communicating with each other, and a plurality of communication ports formed with respect to one common port. It is ink jet recording head according to claim 1 or 2. The ink jet recording head according to claim 3 , wherein the columnar portion extends perpendicularly to a surface of the orifice portion on the flow path side. The ink jet recording head according to claim 4 , wherein a center axis of the communication port and a center axis of the columnar part coincide with each other. A plurality of the columnar portions are provided for one communication port,
It said plurality of columnar portions extends from a position facing the corner portion of the communication port of the orifice portion, the ink jet recording head according to claim 3 or 4. A method for producing an ink jet recording head having a cleaning process includes flowing fluid to the supply port through the flow path from the discharge ports of the ink jet recording head according to any one of claims 1 to 6.

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