JP2017154322A - Method for manufacturing liquid discharge head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To manufacture a liquid discharge head in which water repellency of its surface to which a discharge port opens does not easily decrease.SOLUTION: A method for manufacturing a liquid discharge head including a member for forming a discharge port that discharges a liquid includes a step of preparing a member containing nanoparticles and having its surface to which some of the nanoparticles are exposed, a step of removing the nanoparticles exposed to the surface of the member to form a recess formed by removing the nanoparticles on the surface of the member, and a step of forming the discharge port on the surface of the member.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a method for manufacturing a liquid discharge head.

  A liquid discharge apparatus represented by an ink jet printer has a liquid discharge head. The liquid discharge head is provided with a discharge port, and the liquid is discharged from the discharge port. In such a liquid discharge head, if a large amount of liquid adheres to the discharge port surface, which is the surface where the discharge port opens, the liquid discharge may be affected. For this reason, it is known that the discharge port surface is subjected to water repellent treatment to make it difficult for liquid to adhere to the discharge port surface.

  On the other hand, as a method for water-repellent treatment of the surface of the structure, Patent Document 1 discloses that the surface of the laminate is sprayed on the surface of the laminate by spraying hydrophobic oxide fine particles having an average primary particle diameter of about 3 to 100 nm. The water repellent treatment is described.

JP 2011-93315 A

  Even if the liquid ejection head is subjected to a water repellent treatment, the liquid does not adhere at all, so that the liquid may be wiped off by a wiper or the like. According to the study by the present inventors, when the method described in Patent Document 1 is applied to the water-repellent treatment of the discharge port surface of the liquid discharge head, the hydrophobic oxide fine particles are formed by wiping off the wiper or the like of the discharge port surface. It has been found that water repellency may be reduced. Further, it has been found that even when there is some contact other than the wiper on the discharge port surface, the hydrophobic oxide fine particles are also removed from the discharge port surface and the water repellency may be lowered.

  Accordingly, an object of the present invention is to manufacture a liquid discharge head in which the water repellency of the surface where the discharge port is open is unlikely to decrease.

  The present invention is a method of manufacturing a liquid discharge head having a member that forms a discharge port for discharging a liquid, the step of preparing a member that contains nanoparticles and a part of the nanoparticles are exposed on the surface; Removing a nanoparticle exposed on the surface of the member to form a recess formed by removing the nanoparticle on the surface of the member; and forming a discharge port on the surface of the member. The present invention relates to a method for manufacturing a liquid discharge head.

  According to the present invention, it is possible to manufacture a liquid discharge head in which the water repellency of the surface where the discharge port is open is unlikely to decrease.

FIG. 4 is a diagram illustrating a method for manufacturing a liquid discharge head. FIG. 4 is a diagram illustrating a method for manufacturing a liquid discharge head. FIG. 4 is a diagram illustrating a method for manufacturing a liquid discharge head. FIG. 4 is a diagram illustrating a liquid discharge head.

  FIG. 4 shows an example of a liquid discharge head manufactured by the manufacturing method of the present invention. The liquid discharge head manufactured by the present invention includes a substrate 1 and a member 3 that forms a discharge port 2 on the substrate 1.

  The substrate 1 is made of silicon or the like. The substrate 1 is provided with a supply port 4 penetrating the substrate. The supply port 4 opens on the surface of the substrate 1. On the substrate, an energy generating element 5 made of a heating resistor element or a piezoelectric element is provided. There is a member 3 on the substrate, and a discharge port 2 is formed at a position facing the energy generating element 5 of the member 3. The surface of the member 3 where the discharge port 2 is open is a discharge port surface 2a. There are terminals 6 at both ends on the substrate, and an electrical signal is sent to the energy generating element 5 from the outside of the liquid discharge head via the terminals 6, thereby driving the energy generating element. The liquid is supplied from the supply port 4 to the liquid chamber on the substrate, and is discharged from the discharge port 2 by being given energy by the energy generating element 5 driven in the liquid chamber. The liquid discharged from the discharge port 2 lands on a recording medium such as paper. In this way, characters and images are recorded.

  In the liquid discharge head of the present invention, the discharge port surface 2a where the discharge port of the member 3 is open is water repellent. Hereinafter, a method for manufacturing a liquid discharge head having a water-repellent discharge port surface will be described.

<Embodiment 1>
Next, a method for manufacturing the liquid ejection head in Embodiment 1 will be described with reference to FIG.

  First, as shown in FIG. 1A, a substrate 1 having an energy generating element 5 is prepared. The energy generating element 5 is covered with an insulating layer 7 and a protective layer 8. Examples of the insulating layer 7 include a layer formed of SiN, SiC, SiCN, or the like. Examples of the protective layer 8 include a layer formed of Ta, Ir, or the like.

  Next, as shown in FIG. 1B, a mold material 9 is provided on the substrate. The mold material 9 is formed, for example, by applying a positive photosensitive resin on a substrate, and exposing and developing the same. By removing the mold member 9, the removed part becomes a liquid chamber or a liquid flow path. Therefore, it forms in the part which forms a liquid chamber or a flow path of a liquid. The mold member 9 can be formed of metal or the like in addition to the resin.

  Next, as illustrated in FIG. 1C, the member 3 is provided so as to cover the mold material 9. A discharge port is formed in the member 3 later. The member 3 contains nanoparticles. It is preferable that nanoparticles contained in the member 3 exist on the surface side of the member 3 provided on the substrate. Furthermore, it is more preferable that a part of the nanoparticles is exposed on the surface side of the member 3. In order for the nanoparticles to exist at such a position, it is preferable to make the nanoparticles as follows. First, when forming the member 3 by application | coating on a board | substrate, it is preferable that the nanoparticle contains the fluorine. This is because if the nanoparticles contain fluorine, the nanoparticles move in the direction closer to the surface of the member 3 due to the segregation action of fluorine and are easily exposed. On the other hand, when the member 3 is a dry film, the nanoparticles preferably do not contain fluorine. A dry film is generally first formed on a support film. Nanoparticles that do not contain fluorine move in the direction of sedimentation in the dry film. That is, it moves to the bottom side opposite to the surface. However, when this dry film is transferred to the substrate 1, the bottom side of the dry film is the surface side of the member. Therefore, when the support film is removed, the nanoparticles are gathered on the surface side of the member 3 and are easily exposed on the surface.

The nanoparticles are also present inside the member 3. The surface of the member is a surface opposite to the surface on which the substrate 1 is provided when viewed from the member 3. The nanoparticles are preferably particles formed of metal. As the nanoparticles, it is preferable to use particles having a number average primary particle diameter of 20 nm or less. Although the number average primary particle diameter of the nanoparticles is 20 nm or less, as will be described later, fine concave portions are easily formed on the surface of the member 3, and water repellency is easily exhibited well. The lower limit is preferably 5 nm or more from the viewpoint of availability. Further, as the nanoparticles, it is preferable to use particles having a BET specific surface area of 90 m ² / g or more. Even when the BET specific surface area is 90 m ² / g or more, fine concave portions are easily formed on the surface of the member 3, and water repellency is easily exhibited well.

  Next, a discharge port is formed in the member 3. Here, an example in which the member 3 contains nanoparticles and a negative photosensitive resin will be described. First, as shown in FIG. 1D, exposure is performed through a mask 10. By this exposure, the member 3 is made to have a latent image of a portion that will later become a discharge port. Further, the member 3 is heated and cured. In particular, when the discharge port is formed by photolithography as described above, it is necessary to prevent the nanoparticles from absorbing light and preventing curing. From this point, as the nanoparticles, the number average primary particle diameter having a high transmittance with respect to the wavelength 365 nm often used as the exposure light, the fumed silica having a refractive index close to that of the resin often used for the member 3 is 20 nm. The following alumina is preferably used.

Subsequently, the member 3 is etched as shown in FIG. This etching is preferably etching that does not etch the nanoparticles but etches other components contained in the member, here, the negative photosensitive resin. Here, etching is performed by O ₂ plasma treatment. In particular, when fumed silica is used as the nanoparticles, O ₂ plasma is preferable in that it does not etch fumed silica. Further, the etching of the member 3 is preferably isotropic etching. By this step, the member 3 is etched, and some of the nanoparticles on the surface of the member 3 are selectively left on the surface of the member 3, so that the nanoparticles are exposed well. In addition, when the nanoparticle has already been exposed on the surface of the member 3, this etching may not be performed.

  In this manner, a member containing nanoparticles and having a part of the nanoparticles exposed on the surface is prepared. Subsequently, the nanoparticles exposed on the surface of the member 3 are removed. The removal of the nanoparticles is performed by wet etching, for example. In addition, it can be removed by dry etching, or can be removed by a wiper or the like. However, wet etching is preferably used in that the nanoparticles are more selectively removed from the surface of the member 3. Wet etching is performed using an acid such as hydrofluoric acid if the nanoparticles are fumed silica, or an alkaline solution such as an aqueous TMAH solution if alumina. For example, the fumed silica can be removed by vapor etching with anhydrous hydrofluoric acid. In this manner, by removing the nanoparticles exposed on the surface of the member 3, a recess formed by removing the nanoparticles on the surface of the member 3 is formed. That is, the part in which the part of the nanoparticle is buried on the surface of the member 3 becomes a concave part by removing the nanoparticle. A recess is formed in the discharge port surface which is the surface of the member 3, and the water repellency is expressed by the recess.

  Next, as shown in FIG. 1 (f), the latent image of the member 3 is developed to form the discharge port 2 in the member 3. Since the nanoparticles are very small, the recesses formed by removing the nanoparticles are also very small, so the recesses are not shown. In addition, although an example in which the discharge port 2 is formed by photolithography has been described here, the discharge port 2 can also be formed by dry etching or laser. Further, the discharge port may be formed before the nanoparticles are removed from the surface of the member 3.

  Finally, the member 3 on which the discharge port is formed is protected with a protective film or the like, and the supply port 4 is formed on the substrate 1. Subsequently, as shown in FIG. 1 (g), the mold material 9 is removed from the supply port 4, thereby forming a liquid chamber and a flow path inside the member 3. Finally, separation and cutting of the plurality of substrates 1 and electrical joining for driving the energy generating elements 5 are performed as necessary to manufacture a liquid discharge head.

<Embodiment 2>
In the first embodiment, the member 3 is formed of one layer, but the member 3 may be formed of a plurality of layers. In the second embodiment, an example in which the member 3 is formed of two layers will be described with reference to FIG.

  The processes up to the step of providing the mold material on the substrate are the same as those in the first embodiment. Next, as shown to Fig.2 (a), the member 3a which is a part (lower layer) of the member 3 is provided so that the type | mold material 9 may be coat | covered. The member 3a preferably contains a resin. Moreover, the member 3a may contain the nanoparticle and does not need to contain it. However, if the member 3 is divided into a plurality of layers so that the lower layer (substrate side layer) has a photosensitive function and the upper layer has a water-repellent function, the member 3a contains nanoparticles. Or at least the content is preferably lower than that of the upper layer. The member 3a is formed by, for example, a spin coater, and the thickness is preferably 15.0 μm or more and 50.0 μm or less. On the member 3a, a member 3b is further provided as an upper layer. The member 3b contains nanoparticles. Moreover, it is preferable to contain resin. The member 3 b is the outermost layer among the layers constituting the member 3. When forming the member 3b, it is necessary to prevent the solvent or the like in the material forming the member 3b from dissolving the member 3a. For this reason, it is preferable to form the member 3b by application | coating with a slit coating device, for example. The thickness of the member 3b is preferably 0.1 μm or more and 5.0 μm or less. The thickness of the member 3b is more preferably 1.5 μm or less.

  The subsequent steps are basically the same as those in the first embodiment. First, as shown in FIG. 2B, exposure is performed through a mask 10. By this exposure, the member 3a and the member 3b are caused to have latent images of portions that will later become discharge ports. Further, the member 3 is etched as shown in FIG. And as shown in FIG.2 (d), the discharge port 2, the supply port 4, a liquid chamber, etc. are formed. Finally, separation and cutting of the substrate 1 and electrical bonding for driving the energy generating element 5 are performed to manufacture a liquid discharge head.

  As in the second embodiment, by forming the mold material 9 with a plurality of layers, functional separation in each layer can be remarkably exhibited.

<Embodiment 3>
Although the mold material 9 is formed in the first and second embodiments, the mold material may not be formed in the present invention. Embodiment 3 is a form which does not form a mold material.

  First, similarly to the first embodiment, a substrate 1 having an energy generating element 5 and the like is prepared. A dry film 11 is formed on the substrate 1 by transfer as shown in FIG. As the dry film 11, for example, a negative photosensitive resin is used.

  Next, as shown in FIG. 3B, the dry film 11 is exposed and further heated to cause the dry film 11 to have a latent image of the shape of the liquid chamber.

  Next, as shown in FIG. 3C, the member 3 a and the member 3 b are formed on the dry film 11. The members 3a and 3b are formed in the same manner as in the second embodiment. The members 3a and 3b are preferably formed by application using a slit coating apparatus.

  Next, as shown in FIG. 3D, exposure is performed through the mask 10. By this exposure, a latent image is formed on the member 3a and the member 3b in a portion that will later become an ejection port. Furthermore, as shown in FIG.3 (e), the dry film 11, the member 3a, and the member 3b are hardened.

  Next, as shown in FIG. 3F, the members 3a and 3b are etched in the same manner as in the first and second embodiments. Then, the nanoparticles exposed on the surface of the member 3b are etched with a hydrofluoric anhydride vapor etcher to form a recess on the surface of the member 3b.

  Then, as shown in FIG. 3G, the discharge port 2 and the liquid chamber are formed, and then the supply port 4 is formed as shown in FIG. Finally, separation and cutting of the substrate 1 and electrical bonding for driving the energy generating element 5 are performed to manufacture a liquid discharge head.

  Hereinafter, the present invention will be described more specifically with reference to examples.

Example 1
First, as shown in FIG. 1A, a substrate 1 having an energy generating element 5 was prepared. As the substrate 1, a silicon substrate formed of silicon single crystal was used. As the energy generating element 5, an element formed of TaSiN was used. The energy generating element 5 is covered with an insulating layer 7 made of SiN, and a protective layer made of Ta is further provided thereon.

  Next, as shown in FIG. 1B, a mold material 9 was provided on the substrate 1. The mold material 9 was coated with a positive photosensitive resin (trade name: ODUR-1010, manufactured by Tokyo Ohka Kogyo Co., Ltd.) with a thickness of 14 μm, exposed with a proximity exposure machine UX-3300 (manufactured by Ushio Electric), and patterned.

  Next, the member 3 was provided as shown in FIG.1 (c). The member 3 is a coating liquid containing an epoxy resin (trade name; EHPE3150, manufactured by Daicel) which is a photosensitive resin, fumed silica (trade name; manufactured by Nippon Aerosil Co., Ltd.) as a nanoparticle, and a photoinitiator. Was formed by coating so as to cover the mold material 9. The content ratio of the fumed silica was 10% by mass with respect to the total solid content of the coating liquid. Fumed silica was exposed on the surface of the member 3.

  Next, as shown in FIG. 1 (d), exposure is performed with a mask 10 using a stepper (trade name; FPA3000-i5 +, manufactured by Canon), followed by spin coater (trade name; CDS-8000, manufactured by Canon). Was baked at 90 ° C.

  Next, as shown in FIG.1 (e), the member 3 was etched with the chemical dry etching apparatus (brand name; CDE-7-4, product made by Shibaura Eletech). The etching amount was 0.5 μm in the thickness direction of the member 3 (direction perpendicular to the surface of the substrate). By this etching, fumed silica was exposed on the surface of the member 3. Subsequently, etching with hydrofluoric acid was performed with a hydrofluoric anhydride vapor etcher (Memstar) to remove the fumed silica exposed on the surface of the member 3.

  Next, as shown in FIG. 1 (f), development is performed using a developer (trade name: ODUR-1010 developer, manufactured by Tokyo Ohka Kogyo Co., Ltd.) using ACT-8 manufactured by Tokyo Electron, and a discharge port 2 is formed on the member 3. Formed.

  Finally, as shown in FIG. 1G, the substrate 1 was etched with tetramethylammonium hydroxide to form the supply port 4. In this way, a liquid discharge head was manufactured.

(Example 2)
The steps up to the step of FIG. 1B in Example 1 were the same as in Example 1. However, the thickness of the mold formed in Example 1 was 25 μm. In Example 2, another mold material (upper layer) was further provided on the mold material (lower layer). The coating solution for the upper layer is adjusted so that the solid content concentration is 50% by mass using a solution containing an epoxy resin containing a solid content of 58% by mass and alumina having a solid content concentration of 16% by mass. And created. This coating solution was applied to the lower layer with a thickness of 1 μm using a slit coating device.

  Thereafter, a liquid discharge head was manufactured in the same manner as in Example 1 except that the alumina was removed with another developer (trade name; NMD-3, manufactured by Tokyo Ohka Kogyo Co., Ltd.). .

(Example 3)
As shown in FIG. 3A, the dry film 11 was transferred onto the substrate 1 prepared in the same manner as in Example 1. The dry film 11 is obtained by forming a dry film on a support film made of PET (polyethylene terephthalate) with a nozzle material in which the amount of photoinitiator is adjusted so that the sensitivity is 1/10 of the member 3a described later. Used and transferred under vacuum. The thickness of the dry film 11 was 14 μm.

Next, as shown in FIG. 3B, the dry film 11 was exposed at 1000 J / m ² and further baked at 90 ° C.

  Next, as shown in FIG. 3C, the member 3 a was formed on the dry film 11 by a dry film having a sensitivity 10 times higher than that of the dry film 11. The thickness of the member 3a was 11 μm. Subsequently, the same material as the upper layer of Example 2 was used to form a member 3b having a thickness of 1 μm.

  Thereafter, in the same manner as in Example 1, a liquid discharge head was manufactured by a process as shown in FIG.

(Comparative example)
In Example 1, fumed silica was contained in the coating liquid forming the member 3, but in the comparative example, fumed silica was not contained. Instead, before exposing the member 3 formed of an epoxy resin, fumed silica was sprayed on the surface of the member 3 to adhere the fumed silica to the surface of the member 3.

  Except for this, a liquid discharge head was manufactured in the same manner as in Example 1.

<Evaluation>
Each of the liquid discharge heads manufactured in Examples 1 to 3 and the comparative example was electrically joined and incorporated in the liquid discharge head. Immediately after incorporation, liquid was ejected from each liquid ejection head, and the landing position on the recording medium was confirmed with an electron microscope. As a result, the liquid landed at a desired position in any liquid ejection head.

  Next, the discharge port surface of each liquid discharge head was wiped with a wiper 2000 times. After wiping, liquid was discharged from each liquid discharge head in the same manner, and the landing position on the recording medium was confirmed with an electron microscope. As a result, in the liquid discharge heads of the first to third embodiments, the liquid has landed at a desired position, whereas the liquid discharge head of the comparative example has a higher landing accuracy than the liquid discharge heads of the first to third embodiments. It was low. This is probably because the water repellency of the liquid discharge head of the comparative example was deteriorated with time due to wiping, whereas the liquid discharge heads of Examples 1 to 3 were able to maintain stable water repellency.

Claims (14)

A method of manufacturing a liquid discharge head having a member that forms a discharge port for discharging liquid,
A step of containing a nanoparticle and preparing a member in which a part of the nanoparticle is exposed on the surface;
Removing the nanoparticles exposed on the surface of the member to form a recess formed by removing the nanoparticles on the surface of the member;
Forming a discharge port on the surface of the member;
A method of manufacturing a liquid discharge head, comprising:   The method of manufacturing a liquid ejection head according to claim 1, wherein the member contains the nanoparticles and a resin.   The method for manufacturing a liquid discharge head according to claim 2, wherein the resin is a photosensitive resin.   The method of manufacturing a liquid ejection head according to claim 1, wherein the nanoparticles are particles formed of metal.   The method of manufacturing a liquid ejection head according to claim 4, wherein the nanoparticles are particles formed of fumed silica.   The method of manufacturing a liquid discharge head according to claim 4, wherein the nanoparticles are particles formed of alumina.   The method of manufacturing a liquid ejection head according to claim 1, wherein the nanoparticles are particles having a number average primary particle diameter of 20 nm or less. The method of manufacturing a liquid ejection head according to claim 1, wherein the nanoparticles are particles having a BET specific surface area of 90 m ² / g or more.   The method of manufacturing a liquid discharge head according to claim 1, wherein the discharge port is formed by exposing and developing the member.   10. The method of manufacturing a liquid ejection head according to claim 1, wherein the member is formed of a plurality of layers, and an outermost layer of the plurality of layers contains the nanoparticles.   The method of manufacturing a liquid ejection head according to claim 10, wherein the thickness of the outermost layer is not less than 0.1 μm and not more than 5.0 μm.   The method of manufacturing a liquid ejection head according to claim 1, wherein the removal of the nanoparticles is performed by etching with an acid or an alkali.   The method of manufacturing a liquid ejection head according to claim 1, wherein the surface of the member is etched before the step of removing the nanoparticles and forming a recess on the surface of the member. The method of manufacturing a liquid ejection head according to claim 13, wherein the etching of the surface of the member is etching by O ₂ plasma.

Images