JP6388385B2 - Liquid discharge head and method of manufacturing liquid discharge head - Google Patents

Description

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

A typical example of a liquid discharge head that discharges liquid is a liquid discharge head that performs recording by discharging droplets onto a recording medium. A liquid discharge head generally includes a discharge port for discharging a liquid, a liquid chamber and a pressure chamber communicating with the discharge port, and an energy generation unit provided in the liquid chamber.
The liquid ejection head performs recording by ejecting liquid droplets from the ejection port by driving the energy generating unit. For this reason, the shape of the discharge port and the surface state of the discharge port forming member near the discharge port affect the liquid discharge performance.
In recent years, in order to realize high-quality printing, the liquid discharge head has been miniaturized and a high-definition discharge port capable of discharging a liquid of 5 pl or less is mounted on the liquid discharge head. The diameter of the discharge port and the thickness of the nozzle wall that separates the liquid chamber formed so as to communicate with the discharge port tend to be small enough to support high-quality printing, and both the diameter of the discharge port and the thickness of the nozzle wall are both There is a portion of 10 μm or less.
Moreover, the strength of the discharge port with respect to external force is also decreasing with miniaturization. In order to protect the discharge port finely processed as described above, a protective tape is attached to the first surface on which the discharge port of the liquid discharge head is formed. The protective tape needs to be peeled off by the user when using the liquid discharge head.
The protective tape includes a base film and an adhesive layer that bonds the base film and the liquid discharge head. If the adhesive strength of the adhesive layer is strong, the liquid ejection head may be destroyed when the user peels off the protective tape. On the other hand, if the adhesive strength is weak, the function of the protective tape cannot be fully exhibited, for example, the tape is peeled off during distribution.

In Patent Document 1, for the purpose of solving the above problems, the surface of a specific portion of the liquid discharge head subjected to the liquid repellent treatment is modified to change the adhesion (adhesive strength) to the protective tape, A manufacturing method for increasing the adhesion of a region where no discharge port is formed is disclosed.
According to the method disclosed in Patent Document 1, active oxygen is generated by irradiating a specific part of the surface of a liquid discharge head subjected to liquid repellency treatment using an alkylsiloxane epoxy resin containing fluorine with ultraviolet rays. Let By combining with the generated active oxygen, a functional group containing an oxygen atom such as a hydroxyl group (OH) is formed on the surface of the liquid ejection head, the amount of oxygen on the surface is increased, and the chemical bonding efficiency is improved. The adhesion between the surface of the liquid discharge head and the protective tape is improved.

JP 2007-313890 A

However, the method described in Patent Document 1 relatively improves the adhesion of the protective tape in a part of the liquid repellent layer by surface modification. For this reason, in a liquid discharge head having a surface with high adhesion such that no liquid repellent layer is formed, the surface modification effect by ultraviolet irradiation is low, and it is difficult to express a desired difference in adhesion. is there. Further, in recent years, the size of the liquid discharge head has been reduced, so that the area where the discharge port for surface modification is not formed is reduced, and fine alignment when irradiating ultraviolet rays becomes difficult. It is coming.
An object of the present invention is to provide a liquid discharge head in which a region having a strong and weak adhesion of a protective tape is formed with high accuracy according to the surface structure of the liquid discharge head, and a method for manufacturing the same.

A liquid discharge head according to the present invention includes a discharge port forming member having a discharge port forming surface on which a discharge port is formed , and a liquid discharge head in which a protective tape is attached to the discharge port forming surface .
On the surface opposite to the discharge port forming surface of the discharge port forming member and forming the flow channel communicating with the discharge port, a projecting portion having an arc-shaped cross section protruding into the flow channel is formed. A recess having an arc-shaped cross section is formed on the surface corresponding to the protrusion , and the protective tape is attached to the discharge port forming surface so as to cover the recess and the discharge port.
The manufacturing method of the liquid discharge head of the present invention includes
A method for manufacturing a liquid discharge head having a depression on a discharge port forming surface to which a protective tape is attached,
Forming a mold material layer on a recessed area of the substrate or a surface having an opening of the through-hole, and forming a depression following the recessed area of the substrate or the opening of the through-hole on the surface of the mold material layer;
Forming the discharge port forming surface on the surface having the recess of the mold material layer, and forming a recess that follows the recess of the mold material layer on the discharge port forming surface;
It is characterized by having.
As described above, a depression is formed on the discharge port forming surface. Since the protective tape does not adhere to the discharge port forming surface or is shallowly adhered at the recessed portion, the adhesion is weaker than other portions.

  According to the present invention, since the contact area with the protective tape is reduced at the recessed portion and the adhesion is reduced, a strong and weak area can be easily and accurately formed on the surface of the liquid ejection head. it can.

It is sectional drawing which shows an example of the liquid discharge head which concerns on this invention. (A)-(e) is sectional drawing which shows an example of the manufacturing method of the liquid discharge head concerning this invention. It is a perspective view which shows an example of the liquid discharge head which concerns on this invention. It is a perspective view which shows an example of the liquid discharge head which concerns on this invention. It is sectional drawing which shows an example of the liquid discharge head which concerns on this invention. (A)-(e) is sectional drawing which shows an example of the manufacturing method of the liquid discharge head concerning this invention. (A)-(g) is sectional drawing which shows an example of the manufacturing method of the liquid discharge head concerning this invention.

[Liquid discharge head]
FIG. 3 is a perspective view showing an example of the liquid discharge head according to the present invention. FIG. 1 is a cross-sectional view of the liquid discharge head of FIG. 3 taken along the line AA.
As shown in FIG. 1, the liquid discharge head 20 includes a substrate 1, a resist 31 that forms the pressure chamber 11 (also referred to as a flow path forming member), and a resist 4 that includes the discharge ports 12 (also referred to as a discharge port forming member). ). A liquid discharge energy generating element 10 is provided on the substrate 1, and a protective layer 2 that covers the substrate 1 and the liquid discharge energy generating element 10 is formed. Further, a liquid supply port 13 penetrating the substrate 1 and the protective layer 2 is formed. A recess 6 that is recessed toward the substrate 1 is formed on the surface on which the discharge port 12 is formed. The recess 6 is formed between the protective layer 2 and the resist 4 and at the edge of the liquid supply port 13. Resist 32, 33 is provided.

[Liquid discharge head manufacturing method 1]
Hereinafter, embodiments of the present invention will be described in detail with reference to FIGS. 1 to 3. FIG. 2 is a part of the AA sectional view of the liquid discharge head shown in FIG. 3 (portion of the discharge port 12). The method according to the present invention is not limited to these.
First, as shown in FIG. 2A, a resist 3 as a negative photosensitive first layer is formed on a silicon substrate 1 on which a liquid discharge energy generating element 10 and a protective layer 2 are formed. . Examples of the liquid discharge energy generating element 10 include an electrothermal conversion element and a piezoelectric element. As a material of the protective layer 2, SiO ₂ or the like can be used. As the resist 3, a chemically amplified resist can be used. As the polymer material component contained in the resist 3, an epoxy resin, a silicon polymer compound, a vinyl polymer compound having a hydrogen atom at the α-position, or the like can be used. Among these, an epoxy resin is preferable. Examples of the epoxy resin include phenol novolac type epoxy resins, cresol novolac type epoxy resins, and epoxidized rubbers such as epoxidized polybutadiene. These may use 1 or more types, and may use 2 or more types together. The resist 3 can contain a photoacid generator. As the photoacid generator, a triarylsulfonium salt, an onium salt, or the like can be used. These may use 1 or more types, and may use 2 or more types together. Further, the resist 3 can contain a solvent. As the solvent, propylene glycol monomethyl ether acetate (PGMEA), γ-butyrolactone, or the like can be used. One of these may be used alone, or two or more of these may be used in combination. The boiling point of the solvent is preferably 100 ° C. or higher and 250 ° C. or lower. The boiling point can be selected based on literature values. These solvents can also be used as a solvent contained in the second negative photosensitive resist 4 described later and a solvent contained in the resin film 5 applied on the second negative photosensitive resist 4. . Further, the same solvent may be used for forming the resist 3, the resist 4, and the resin film 5.

The proportion of the polymer material component contained in the resist 3 can be, for example, 19.9 mass% or more and 70.0 mass% or less. As a ratio of the photo-acid generator contained in the resist 3, it can be 0.1 mass% or more and 2.5 mass% or less, for example. As a ratio of the solvent contained in the resist 3, it can be 29.9 mass% or more and 80.0 mass% or less, for example.
Examples of the method for forming the resist 3 include a solvent coating method, a method of producing a dry film, and transferring it onto a substrate. The solvent coating method is a method of forming a resist layer by applying a resist solution on a substrate with a spin coater, a roll coater, a wire bar or the like and then drying and removing the solvent. For example, the resist 3 can be formed by applying a solution containing a polymer material component, a photoacid generator, and a solvent onto the substrate 1 by spin coating and drying. The film thickness of the resist 3 is not particularly limited, but can be, for example, 5 μm or more and 30 μm or less.

Next, as shown in FIG. 2B, as a partial exposure process to the resist 3, the resist 3 is selectively exposed through a mask 40 to form a latent image. Thereafter, a baking process (hereinafter referred to as PEB: Post Exposure Bake) is performed to cure the resists 31, 32, and 33 in the region irradiated with light to form a wall material layer. Here, the portion not selectively irradiated with light is left in an uncured state to become a mold material layer, and the pressure chamber 11 is formed in a space after the mold material layer is removed from the substrate. For the region corresponding to the recess 6 (X in FIG. 2B) for which the adhesive strength to the protective tape is relatively lowered, resists 32 and 33 are formed, and the region sandwiched between these is used as a mold material layer. In the subsequent PEB process, the region X, that is, the surface of the mold material layer is selectively recessed to form a recessed region Y in the resist 4 described later. For the exposure, ultraviolet rays, ionizing radiation, or the like can be used. Although the amount of exposure is not particularly limited as long as a desired pattern can be formed, for example, it can be 3000 J / m ² or more and 10,000 J / m ² or less. The temperature and time of PEB are not particularly limited as long as a desired pattern can be formed. For example, it can be performed at 40 ° C. or higher and 105 ° C. or lower for 3 minutes or longer and 15 minutes or shorter.
In order to satisfactorily form a depression in the X region, the width of the light irradiation region (the width shown in FIG. 2) is preferably 4 μm or more and 1.5 mm or less. More preferably, it is 10 μm or more. Moreover, it is 200 micrometers or less. The depth of the light irradiation region is preferably 0.5 μm or more and 50 μm or less from the viewpoint of the strength of the resists 3 and 4. More preferably, it is 3 μm or more. Moreover, it is 25 micrometers or less.

Next, as shown in FIG. 2C, a resist 4 as a second negative photosensitive resist is formed as a second layer on the resist 3 including the resists 31-33, that is, on the first layer. To do. As the resist 4, a chemically amplified resist can be used. The resin component contained in the resist 4 is preferably an epoxy resin, and the same resin component as that which can be contained in the resist 3 can be used. The resist 4 can contain a photoacid generator. The photoacid generator is not particularly limited as long as it can form a desired pattern, and the same photoacid generator as that contained in the resist 3 can be used. Further, the resist 4 can contain a solvent. As the solvent, PGMEA, γ-butyrolactone, or the like can be used. One of these may be used alone, or two or more of these may be used in combination. The boiling point of the solvent is preferably 100 ° C. or higher and 250 ° C. or lower. The resist 4 may include a component that suppresses diffusion of the acid generated by the light absorbing material and the photo acid generator (hereinafter also referred to as an absorbing material). The absorbent material is not particularly limited as long as it can form a desired pattern.
As a ratio of the resin component contained in the resist 4, it can be 19.9 mass% or more and 70.0 mass% or less, for example. As a ratio of the photo-acid generator contained in the resist 4, it can be 0.1 mass% or more and 2.5 mass% or less, for example. As a ratio of the solvent contained in the resist 4, it can be 29.9 mass% or more and 80.0 mass% or less, for example.
The solubility parameter (SP value) of the resist 4 is preferably 5 or more and 13 or less. In the present invention, the SP value is a value estimated from a physical property value. Specifically, since the solubility parameter δ is defined as δ = √ (ΔH−RT) / V where the evaporation enthalpy is ΔH and the molar volume is V, the physical property values of each material are quoted from the literature. Can be estimated.

Examples of the method for forming the resist 4 include a solvent coating method, a method of producing a dry film, and transferring it onto the resist 3. Any method can be selected as long as the region corresponding to the recess 6 (Y in FIG. 2C) for which the adhesive force to the protective tape is relatively lowered can be formed in a recessed state. Good.
The film thickness of the resist 4 is not particularly limited, but can be, for example, 3 μm or more and 60 μm or less. However, from the viewpoint of forming a depressed state, it is preferably 3 μm or more and 15 μm or less, and more preferably 3 μm or more and 8 μm or less.
Subsequently, as shown in FIG. 2D, the resist 4 is selectively exposed collectively through a mask 41 to form a latent image on the discharge port pattern, and then PEB is performed. The exposure conditions and PEB conditions are not particularly limited as long as a desired discharge port pattern can be formed. For the exposure, for example, ultraviolet rays or ionizing radiation can be used. Exposure amount, for example, 400 J / m ² or more, it is possible to 2000J / m ² or less. About the temperature and time of PEB, it can carry out for 3 minutes or more and 10 minutes or less at 70 degreeC or more and 105 degrees C or less, for example.
Next, as shown in FIG. 2E, the resist 3 and the resist 4 are collectively developed to form the pressure chamber 11 and the discharge port 12. Development can be performed using PGMEA or the like. As a result, a discharge port forming member having a recessed recess 6 can be formed in a part of the discharge port forming surface where the discharge port 12 exists.
Next, a liquid supply port 13 (see FIG. 1) is formed in the substrate 1, and the substrate 1 is cut and separated by a dicing saw or the like to form a chip. Thereafter, electrical connection between the terminal for connecting to the drive substrate for driving the liquid discharge energy generating element 10 and the liquid discharge energy generating element 10 is performed. Further, a chip tank member (not shown) for liquid supply is connected to complete the liquid discharge head.

  In the method according to the present invention, a recessed region is formed on the discharge port forming surface where the discharge port of the discharge port forming member is formed. Since the protective tape is not in contact with the region, the adhesion between the liquid discharge head and the protective tape can be reduced. By reducing the overall adhesion while maintaining the adhesion in the vicinity of the discharge port, the protective tape can be peeled without destroying the liquid discharge head while maintaining a desired function.

[Liquid discharge head manufacturing method 2]
In the form of the manufacturing method 1, the recess 6 formed on the discharge port forming surface is formed by exposing the resist 3 and PEB. The present embodiment is a manufacturing method in the case of a substrate in which the liquid supply port 13 is opened, and this embodiment will be described in detail below with reference to FIGS. 5 and 6.
FIG. 5 is a cross-sectional view showing an example of the liquid discharge head according to the present invention, and is a cross-sectional view taken along the line AA of FIG.
As shown in FIG. 5, the liquid discharge head 20 includes a substrate 1, a resist 31 that forms a pressure chamber 11, and a resist 4 that has discharge ports 12. A liquid discharge energy generating element 10 is provided on the substrate 1, and a protective layer 2 that covers the substrate 1 and the liquid discharge energy generating element 10 is formed. Further, a liquid supply port 13 penetrating the substrate 1 and the protective layer 2 is formed. A recess 6 that is recessed toward the substrate 1 is formed on the surface on which the discharge port 12 is formed. In the case of the present embodiment, since the recess 6 is formed using the liquid supply port 13 provided in advance in the substrate 1, the resists 32 and 33 shown in FIG. 1 are not provided.
First, as shown in FIG. 6A, a resist 3 is formed on a substrate 1 on which a through-hole serving as a liquid supply port 13 has been formed in advance. That is, the resist 3 is formed on the surface having the opening of the through hole. The configuration of the substrate 1 and the composition of the resist 3 are in accordance with the manufacturing method 1. Examples of the method for forming the resist 3 include a method in which a dry film is prepared and transferred onto the protective layer 2. The transfer conditions are not particularly limited as long as the resist 3 has a shape that is recessed on the liquid supply port 13, but the transfer temperature is 40 ° C. or more from the general softening point and glass transition point of the resist. It is desirable that the temperature is 180 ° C. or lower. The thickness of the resist 3 is not particularly limited as long as the resist 3 has a shape that is recessed on the liquid supply port 13, but is preferably 20 μm or less.
In the step shown in FIG. 6B, the resist 3 is selectively exposed through the mask 42 to form a latent image of the pattern, and then baking is performed to cure the resist 31 in the region irradiated with light. The portion where the dent is formed is a mold material layer.
The following steps are based on manufacturing method 1. That is, as shown in FIGS. 6C to 6E, the discharge port forming surface is formed on the surface having the depression of the mold material layer, and the depression that follows the depression of the mold material layer is formed on the discharge port formation surface. .
The liquid discharge head formed by the above manufacturing method can reduce the adhesiveness with the protective tape by forming the recess 6 in the region on the liquid supply port 13 on the discharge port forming surface.

[Liquid discharge head manufacturing method 3]
In the manufacturing methods 1 and 2, since the protective tape does not come into contact with the recessed region of the recess 6 by providing the recess 6 that is a recessed region in a partial region of the discharge port forming surface, the adhesiveness is selectively improved. A method of manufacturing a structure that goes down has been described. However, the structure for selectively reducing the adhesion is not limited to this. Even if the protective tape follows the recessed area, the contact area between the protective tape and the discharge port forming surface can be reduced by providing a minute uneven shape in the recessed area of the discharge port forming surface. And can selectively reduce the adhesion. Hereinafter, an embodiment of the present configuration will be described in detail with reference to FIG.

7A to 7C conform to FIGS. 6A to 6C of the manufacturing method 2.
Next, as shown in FIG. 7D, a resin film 5 is formed on the resist 4. The resin film 5 can contain a resin, a solvent, a photoacid generator, an absorber, and a liquid repellent that exhibits liquid repellency. In addition, it is not necessary to add components other than resin and a solvent as needed. The resin contained in the resin film 5 is preferably an epoxy resin, and the same components as those that can be contained in the first negative photosensitive resist 3 can be used. As the solvent, PGMEA, γ-butyrolactone, toluene, α-terpineol, ethyl acetate, acetone, alcohols such as ethanol and butanol, and the like can be used. One of these may be used alone, or two or more of these may be used in combination. The boiling point of the solvent contained in the resin film 5 is preferably 40 ° C. or higher and 250 ° C. or lower, and more preferably 60 ° C. or higher and 150 ° C. or lower. The SP value of the solvent contained in the resin film 5 is preferably 5 or more and 13 or less.
Although the coating method of the resin film 5 is not specifically limited, For example, the coating method by a slit coater, the coating method by spin coating, etc. are mentioned.
The film thickness of the resin film 5 is not particularly limited, but can be 0.2 μm or more and 3.0 μm or less.
Next, as shown in FIG. 7E, the resin film 5 is dried to form minute irregularities 50 on the surface of the recessed area 6 of the liquid ejection head. The temperature condition for drying the resin film 5 can be 40 ° C. or higher and 90 ° C. or lower. The time condition can be 3 minutes or more and 15 minutes or less.
Since the solvent contained in the resin film 5 is volatilized while dissolving the resist 4, when uneven drying occurs, the resin contained in the resist 4 and the resin contained in the resin film 5 are aggregated on the surface of the part that has been volatilized slowly. By doing so, the micro unevenness | corrugation 50 is formed between the parts volatilized early. Since the solvent contained in the resin film 5 is dried so as to collect in the dent 6 in the recessed area where the film thickness of the resin film 5 is thick when volatilized, drying unevenness can be generated in the dent 6. By such an action, it is possible to selectively form minute irregularities on the surface of the resin film 5, and it is possible to selectively form a region having low adhesion to the protective tape.

When it is desired to form a liquid repellent layer on the discharge port forming surface, a liquid repellent film can be obtained by adding a liquid repellent to the resin film 5. In this case, a fluorine-based water repellent, a silicon-based liquid repellent, or the like can be used as the liquid repellent. One of these may be used alone, or two or more of these may be used in combination. The film thickness of the liquid repellent film is preferably 0.1 μm or more and 1.5 μm or less.
The proportion of the solvent contained in the resin film 5 before coating is preferably 5% by mass or more and 95% by mass or less. When the content ratio of the solvent is 5% by mass or more, the resin film 5 can dissolve the resin contained in the resist 4. On the other hand, the amount of resin contained in the resin film 5 capable of forming the minute unevenness 50 can be ensured by being 95% by mass or less.
In order to satisfactorily form the fine unevenness 50 region, it is preferable to cause uneven drying. For this reason, the resin film 5 is preferably a solvent having a saturated vapor pressure of 30 mmHg or higher at 20 ° C. as the solvent and contained in the resin film 5 by 50% or more. More preferably, a solvent having a saturated vapor pressure at 20 ° C. of 40 mmHg or more is used. Further, the resin film 5 contains 60% or more and 95% or less.

After forming the micro concavo-convex region as described above, as shown in FIG. 7F, the resist 4 and the resin film 5 are selectively collectively exposed through the mask 42 to cause the discharge port pattern to become a latent image, Then PEB is performed. The exposure conditions and PEB conditions are in accordance with the manufacturing methods 1 and 2.
Subsequently, as illustrated in FIG. 7G, the resist 3, the resist 4, and the resin film 5 are collectively developed to form the pressure chamber 11 and the discharge port 12. As a result, a discharge port forming member having a recess 6 in which a minute unevenness 50 region is formed on the surface of the recessed region can be formed on a part of the discharge port forming surface where the discharge port 12 exists. The development conditions are in accordance with production methods 1 and 2.

In the method according to the present embodiment, drying unevenness is generated on the surface of the depression 6 which is a recessed area by applying the resin film 5 on the resist 4 having the depression 6 having a recessed surface, and minute unevenness is formed in the portion. 50 is formed. Since the contact area with the protective tape is reduced in the portion with the minute unevenness 50 as compared with the portion without the unevenness, the adhesive force of the protective tape 30 to be applied as shown in FIG. Can be lowered. As a result, regardless of the surface state of the discharge port forming surface, it is possible to easily form a strong region and a weak region with high adhesion on the discharge port forming surface.
The unevenness formed by the present invention has a depth of 0.1 μm to 3.0 μm, and when the resin film 5 is a liquid repellent film, it is as small as 0.1 μm to 1.5 μm. By using a hard or thin protective tape, the adhesion of the region 6 can be reduced. On the other hand, when a protective tape having a soft adhesive layer is used, the adhesive layer enters the minute irregularities, so that the contact area can be increased and the adhesive force can be increased.

[Example 1]
A method of manufacturing the liquid discharge head according to the first embodiment will be described with reference to FIG. 2A to 2E are cross-sectional views illustrating a method of manufacturing a liquid discharge head according to the present embodiment.
First, as shown in FIG. 2A, a first negative photosensitive resist 3 (hereinafter referred to as a resist 3) was formed on a substrate 1. A silicon substrate was used as the substrate 1. The substrate 1 is provided with a liquid discharge energy generating element 10 that is an electrothermal conversion element and a protective layer 2 containing SiO ₂ . Resist 3 includes a resin component composed of an epoxy resin (trade name: SU-8, manufactured by Nippon Kayaku Co., Ltd.), a solvent composed of PGMEA, a photoacid generator composed of a triarylsulfonium salt, and an acid deactivator composed of an amine compound. A solution containing was applied by spin coating and dried. The dry film thickness of the resist 3 was 8 μm. The ratio of the resin component contained in the resist 3 was 60% by mass, the ratio of the photoacid generator was 0.75% by mass, the ratio of the acid deactivator was 0.25% by mass, and the ratio of the solvent was 39% by mass. . A spin coating method was used as a forming method.
Next, as shown in FIG. 2B, the pressure chamber wall pattern was selectively exposed to the resist 3 through a mask 40, and then PEB was performed. Ultraviolet rays were used for exposure. The exposure amount was 10,000 (J / m ² ). PEB was performed at 90 ° C. for 5 minutes. The recessed area in which the recess 6 is formed is provided immediately above the location where the liquid supply port 13 is formed in a later step, and when the width is 100 μm, the amount of recess can be generated up to 3 μm.

Next, a resist 4 was formed on the resist 3 as shown in FIG. The resist 4 is a resist including a resin component made of an epoxy resin (same as the resist 3), a solvent made of PGMEA, and a photoacid generator made of a triarylsulfonium salt. The ratio of the resin component contained in the resist 4 was 50% by mass, the ratio of the solvent was 49% by mass, and the ratio of the photoacid generator was 1% by mass. This resist was used as a dry film. The solvent amount of the resist 4 in the dry film state, that is, the residual solvent amount was 0.1% by weight. The resist 4 was formed by dry film transfer by lamination. The film thickness of the resist 4 was 10 μm.
Next, as shown in FIG. 2D, the discharge port pattern was selectively and collectively exposed to the resist 4 through a mask 41, and then PEB was performed. Ultraviolet rays were used for exposure. The exposure amount was 1000 (J / m ² ). PEB was performed at 105 ° C. for 10 minutes.
Next, as shown in FIG. 2E, the resist 3 and the resist 4 were collectively developed. Development was performed using PGMEA. Thereby, the discharge port formation member in which the hollow 6 dented in the desired area | region was formed was able to be manufactured.
Subsequently, after forming a liquid supply port in the substrate 1, the substrate 1 was cut and separated by a dicing saw into chips, and electrical bonding for driving the liquid discharge energy generating element 10 was performed. Thereafter, a chip tank member for supplying liquid was connected to complete the liquid discharge head.

[Example 2]
In the first embodiment, the discharge port forming member is manufactured in a system in which the liquid supply port is not opened on the substrate. However, in this embodiment, the discharge port forming member is formed using the substrate 1 on which the liquid supply port 13 is formed first. To manufacture.
First, as shown in FIG. 6A, a first negative photosensitive resist 3 (hereinafter referred to as resist 3) was formed on a substrate 1. The substrate 1 is the same as that of the first embodiment. The substrate 1 is provided with a liquid discharge energy generating element 10 that is an electrothermal conversion element, a protective layer 2 containing SiO ₂ , and a liquid supply port 13. Resist 3 was formed according to Example 1. This resist 3 was made into a dry film resist with a film thickness of 10 μm. The solvent amount of the resist 3 in the dry film state, that is, the residual solvent amount was 0.1% by weight. The resist 3 was formed by dry film transfer by lamination. The transfer temperature is set to a temperature exceeding the softening point of the resist 3. When the transfer was performed at 90 ° C. this time, the region X in which the resist 3 was recessed by 4 μm could be formed on the liquid supply port 13.

Next, as shown in FIG. 6B, the pressure chamber wall pattern was selectively exposed to the resist 3 through a mask 42, and then PEB was performed. Ultraviolet rays were used for exposure, and the exposure amount was 10,000 (J / m ² ). PEB was performed at 90 ° C. for 5 minutes.
The procedure after the formation of the second negative photosensitive resist 4 shown in FIG. 6C is the same as that of the first embodiment. As a result, a liquid discharge head in which a recess 6 is formed in a desired region is manufactured. We were able to.

[Example 3]
In the second embodiment, the discharge port forming member includes only the flow path forming member and the discharge port forming member. However, a resin film such as a liquid repellent film may be formed on the surface of the discharge port forming member. In this embodiment, a manufacturing method of an example in which a resin film is formed on the discharge port forming surface will be described. 7A to 7G are cross-sectional views illustrating a method for manufacturing a liquid discharge head according to this embodiment.
7A to 7C are the same manufacturing methods as those in FIGS. 6A to 6C of the second embodiment.
Next, as shown in FIG. 7D, a resin film 5 was applied on the resist 4. Ethanol was used as the solvent for the resin film 5 and an epoxy resin (trade name: SU-8, manufactured by Nippon Kayaku Co., Ltd.) was selected as the resin. The resin film 5 was applied with a slit coater. As the application condition of the resin film 5, 3.0 × 10 ⁻⁹ ml was applied per 1 μm ² . The resin film 5 was dried at 60 ° C. for 10 minutes. As a result, as shown in FIG. 7E, drying unevenness occurred when the solvent of the resin film 5 was volatilized, so that the minute unevenness 50 derived from the resin film 5 was formed on the region 6.
Next, as shown in FIG. 7F, the discharge port pattern was selectively collectively exposed to the resist 4 and the resin film 5 through a mask 41, and then PEB was performed. Ultraviolet rays were used for exposure. The exposure amount was 1000 (J / m ² ). PEB was performed at 105 ° C. for 10 minutes.
Next, as shown in FIG. 7G, the resist 3, the resist 4, and the resin film 5 were collectively developed. Development was performed using PGMEA. As a result, a discharge port forming member in which the minute uneven region 6 was formed in a desired region could be manufactured.
Subsequently, after a liquid supply port was formed in the substrate 1, the substrate 1 was cut and separated into chips by a dicing saw, and electrical bonding for driving the liquid discharge energy generating element 10 was performed. Thereafter, a chip tank member for supplying liquid was connected to complete the liquid discharge head.

As the recesses 6 formed in each of the above-described embodiments, FIG. 3 shows the recesses 6 corresponding to the respective discharge ports between the discharge port rows in which a plurality of discharge ports 12 are provided in a row. The example provided along the arrangement | sequence direction of an exit row | line | column was shown. The shape and arrangement of the recess 6 are not limited to this. A plurality of depressions may be provided for one discharge port, or one depression may be provided for a plurality of discharge ports. Furthermore, a groove-shaped depression may be provided so that the longitudinal direction thereof is orthogonal to the discharge port array. As described above, by selecting the shape to be arranged and the ratio to the discharge port, it is possible to easily form a region having a strong adhesion and a weak region on the discharge port formation surface with high accuracy.
Moreover, it is good also as combining each embodiment. For example, the third embodiment described with reference to FIG. 6 is the same as the second embodiment described with reference to FIG. 5 except that a step of forming the resin film 5 and the minute unevenness 50 is added. In addition to the first embodiment described with reference to FIG.

DESCRIPTION OF SYMBOLS 1 Substrate 2 Protective layer 3 Resist 4 Resist 5 Resin film 6 Depression 10 Liquid discharge energy generating element 11 Pressure chamber 12 Discharge port 13 Liquid supply port 20 Liquid discharge head 30 Protective tape

Claims (8)

In a liquid discharge head comprising a discharge port forming member having a discharge port forming surface on which a discharge port is formed, and a protective tape is attached to the discharge port forming surface .
On the surface opposite to the discharge port forming surface of the discharge port forming member and constituting the flow channel communicating with the discharge port, a projecting portion having an arcuate cross section protruding into the flow channel is formed. The liquid discharge head is characterized in that a recess having an arcuate cross section is formed on the discharge port forming surface corresponding to the protrusion , and the protective tape covers the recess and the discharge port. The discharge port forming surface is provided with a plurality of discharge port arrays with a plurality of discharge ports,
The liquid ejection head according to claim 1, wherein the recess is formed between the plurality of ejection port arrays.   The liquid ejection head according to claim 2, wherein a plurality of the depressions are provided along an arrangement direction of the ejection port arrays. The concave convex surface of the recess is formed, a liquid discharge head according to any of claims 1 to 3. A method for manufacturing a liquid discharge head having a depression on a discharge port forming surface to which a protective tape is attached,
Forming a mold material layer on a recessed area of the substrate or a surface having an opening of the through-hole, and forming a depression following the recessed area of the substrate or the opening of the through-hole on the surface of the mold material layer;
Forming the discharge port forming surface on the surface having the recess of the mold material layer, and forming a recess that follows the recess of the mold material layer on the discharge port forming surface;
A method of manufacturing a liquid discharge head, comprising: A method for manufacturing a liquid discharge head having a depression on a discharge port forming surface to which a protective tape is attached,
Forming a negative photosensitive first layer on the substrate;
A step of forming a wall material layer partially exposed to the first layer and cured by exposure, and a mold material layer left uncured without being exposed;
Baking the first layer that has undergone the exposure process, and forming a depression on the surface of the mold layer; and
Forming a second layer having negative photosensitivity on the first layer that has undergone the baking treatment, and forming a depression that follows the depression on the surface of the mold material layer on the surface of the second layer; ,
Forming a discharge port in the second layer by partially exposing and developing the second layer; and
A method of manufacturing a liquid discharge head, comprising: A resin film containing a solvent capable of dissolving the second layer is provided on the second layer,
The method of manufacturing a liquid ejection head according to claim 6, wherein when the solvent contained in the resin film is volatilized, minute irregularities are formed on the surface of the second layer.   The method for manufacturing a liquid discharge head according to claim 7, wherein the resin film has liquid repellency.

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