JP2014162181A - Manufacturing method of liquid discharge head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method of a liquid discharge head with high reliability having a channel communicating with a discharge port highly accurately formed in it.SOLUTION: A manufacturing method of a liquid discharge head having a channel forming member which forms a discharge port and a liquid channel includes the steps of: forming a channel shape pattern which provides the shape of the liquid channel on a substrate having an energy generation element; forming a resin layer by covering over the channel shape pattern by a photosensitive resin of which absorbance can be controlled; flattening the surface of the resin layer by pressing a translucent member having a flat surface over the surface of the resin layer; partially increasing the absorbance of the resin layer; forming a hardened portion and an unhardened portion in the resin layer by performing exposure processing on the resin layer via the translucent member; reducing the absorbance of the portion of the resin layer of which absorbance has been increased; and forming the discharge port at the unhardened portion, in this order.

Description

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

  In recent years, ink jet recording apparatuses (liquid discharge recording apparatuses) that perform recording by discharging a recording liquid such as ink have been demanded to improve printing performance, particularly high resolution and high speed printing. For this purpose, it is conceivable to achieve high resolution and high-speed printing by reducing the size of the ejected ink and increasing the density of the nozzle array and increasing the number of pixels per unit area.

  For that purpose, since a method for manufacturing a liquid discharge head in which a large number of fine ink discharge ports are formed with high density and high definition is required, various methods have been conventionally proposed. Among these, pattern formation by photolithography using a photosensitive resin material can easily form a good shape having a high aspect ratio with high accuracy.

  Furthermore, the distance between the heater and the ejection port that affects the ejection amount is important in order to enable ejection of minute ink droplets for high-quality recording. However, it is difficult to process the distance between the heater and the discharge port of the ink flow path structure formed of a generally used thin resin layer with high accuracy.

  In order to solve these manufacturing problems, Patent Document 1 discloses a method in which a dry film is used as a coating resin layer, vacuum lamination is performed on the ink flow path pattern, and the coating resin layer is flattened by applying pressure. Has been. According to this manufacturing method, the flatness of the liquid ejection member can be ensured, and the distance between the energy generating element and the nozzle can be shortened with very high accuracy and without variation. For this reason, it is possible to stably maintain the liquid discharge characteristics and to manufacture a liquid discharge head capable of obtaining a high-quality image.

  Further, in Patent Document 2, a method of manufacturing a black matrix, in which a chromic material in a resist material is reacted by heating or light irradiation after the patterning step using a photosensitive resin composition containing a material having chromism characteristics in the resist. Is disclosed. According to this manufacturing method, since it is possible to increase the OD while maintaining the patterning accuracy, it is possible to manufacture a color filter that allows the liquid crystal display device to maintain a high-contrast image.

JP 2006-137065 A JP 2008-233476 A

N. Fujii et al., “Impact of De-molding Force on Exposure Dosage in UV-Nanoimprint Process”, Journal of Photopolymer Science 1 and Technology, Vol. 18, Vol.

  However, in the method of Patent Document 1, since the film thickness distribution of the dry film depends on the accuracy of the base film and the cover film, the dry film has an accuracy of an ink flow path height of several μm to several tens of μm. In some cases, sufficient accuracy cannot be secured. Furthermore, since the base film is peeled from the uncured coating resin layer, defects such as poor peeling may occur in the base film peeling step.

  As a method for solving such a problem, it is conceivable to apply a fine pattern transfer technique called an imprint method. In Non-Patent Document 1, after a mold is pressed against a quartz substrate provided with an ultraviolet curable resin, ultraviolet rays are irradiated through the quartz substrate to cure the resin, and there is a relationship between the peeling force and the ultraviolet irradiation amount when the mold is peeled off. It is stated. It is stated that when the amount of ultraviolet irradiation is increased, the resin is sufficiently peeled and the peeling force is stabilized. However, in this method, since the entire resin is irradiated with ultraviolet rays, there is a problem that a fine pattern such as a discharge port cannot be formed. Further, a method using a mold having a fine light-shielding pattern corresponding to the discharge port is also conceivable. However, there is a problem that the accuracy of the imprint apparatus cannot be sufficiently ensured with respect to the alignment accuracy of the conventional exposure apparatus in which the alignment accuracy of the discharge port pattern of the mold and the energy generating element of the substrate is several tens of nm. If the positional relationship between the energy generating element and the ejection port is different from the desired one, it may lead to troubles such as deviation of the ink ejection direction, generation of satellites, and the like, and printing characteristics may be deteriorated.

  In addition, since the method of Patent Document 2 is a material for black matrix use, it is necessary to maintain a high OD state. Therefore, the chromic material used needs to have irreversible reactivity. However, since this method is an irreversible reaction, there is a problem that the photosensitive resin composition having a high OD cannot be patterned again.

  SUMMARY An advantage of some aspects of the invention is that it provides a highly reliable method of manufacturing a liquid discharge head in which a flow path communicating with a discharge port is formed with high accuracy.

One aspect of the present invention is:
A substrate having an energy generating element for generating energy for discharging a liquid on a first surface, a discharge port for discharging the liquid, and a flow path forming member for forming a liquid flow path communicating with the discharge port; A method for manufacturing a liquid ejection head having:
(1) forming a flow path mold pattern serving as a mold of the liquid flow path on the first surface of the substrate;
(2) A step of coating a photosensitive resin capable of controlling absorbance on the flow path pattern and forming a resin layer;
(3) pressing a translucent member having a flat surface on the surface of the resin layer to flatten the surface of the resin layer;
(4) partially increasing the absorbance of the resin layer;
(5) A step of forming a cured portion and an uncured portion on the resin layer by performing an exposure process on the resin layer through the light transmissive member, and the resin layer portion where the absorbance is increased. An uncured part is formed,
(6) reducing the absorbance of the resin layer portion where the absorbance has increased,
(7) forming the discharge port in the uncured portion;
In this order,
In the steps (4) and (5), the flat surface of the translucent member is brought into contact with the surface of the resin layer.

  According to the present invention, it is possible to provide a highly reliable method for manufacturing a liquid discharge head in which a flow path communicating with a discharge port is formed with high accuracy.

  Preferably, according to the embodiment of the present invention, the variation in the liquid volume of the discharged liquid droplets is further reduced, the liquid droplets of uniform liquid volume can be discharged stably and repeatedly, and the flow communicating with the discharge port A highly reliable liquid discharge head in which the path is formed with high accuracy can be manufactured with high yield.

It is a typical perspective view which shows the structural example of an inkjet recording head. It is a typical cross-sectional process drawing for demonstrating the manufacturing method of the inkjet recording head of this embodiment. It is a typical cross-sectional process drawing for demonstrating the manufacturing method of the inkjet recording head of this embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  In this specification, an ink jet recording head will be mainly described as an example of application of the present invention. However, the scope of application of the present invention is not limited to this, and is applicable to biochip manufacturing and electronic circuit printing. It can also be applied to a recording head or the like. As the recording head, in addition to the ink jet recording head, for example, a head for producing a color filter and the like can be cited.

  The liquid discharge head obtained by the present invention can be mounted on, for example, an apparatus such as a printer, a copier, a facsimile, a word processor having a printer unit, or an industrial recording apparatus combined with various processing apparatuses. . For example, it can be used in devices for uses such as biochip production, electronic circuit printing, and drug spraying.

(Embodiment 1)
FIG. 1 is a schematic perspective view of a part of a liquid discharge head manufactured according to an embodiment of the present invention.

  In FIG. 1, a substrate 1 is formed with an energy generating element 2 that generates energy used to eject a liquid such as ink, and a supply port (not shown) that supplies a liquid to a flow path 3. In addition, a plurality of discharge ports 4 for discharging liquid and a liquid channel 3 communicating with the discharge ports 4 are formed on the substrate 1 having the energy generating element 2 that generates energy used for discharging the liquid. A flow path forming member (discharge port member) 5 is provided.

  In the above configuration, the liquid is supplied from the supply port to the liquid channel 3, and the liquid filled in the liquid channel 3 is discharged from the discharge port 4 by the energy generated by the energy generating element 2 according to the recording signal. . For example, when the energy generating element is an electrothermal converter, bubbles are instantaneously generated in the liquid. Then, using the pressure change caused by the growth of the bubbles, droplets are ejected from the ejection port 4 and recorded on the recording medium.

  Embodiments of the method for manufacturing a liquid discharge head according to the present invention will be described below, but the present invention is not limited to these.

  FIGS. 2A to 2H are flowcharts showing the steps of the method of manufacturing the liquid ejection head in the present embodiment. The liquid ejection head in FIG. 1 is moved in the direction perpendicular to the substrate surface along the broken line AA ′. A part of a cross section in each step when cut is shown.

  As shown to Fig.2 (a), the board | substrate 1 provided with the energy generation element 2 is prepared.

  Although not shown in FIG. 2A, the substrate 1 is provided with an electrical connection such as a wiring for driving the energy generating element 2. A protective layer may be formed on the element for the purpose of improving durability. A silicon substrate is preferable as the substrate 1 because the existing semiconductor manufacturing technology can be easily used in the production of the energy generating element and the electrode.

  In the following description, one liquid discharge head unit is illustrated and described. However, a 6 to 12 inch wafer is used as the substrate 1, a plurality of liquid discharge head units are manufactured at once on one wafer, and one liquid discharge head is obtained by cutting it at the end. You can also.

  Next, as shown in FIG. 2B, a flow path pattern 6 serving as a mold of an ink flow path (liquid flow path) is formed.

  The flow path pattern 6 is formed from, for example, a resin material such as a positive photosensitive resin, a metal, or an inorganic material. For example, a positive photosensitive resin is provided on the substrate 1 by a method of applying a material or a method of laminating a film, and then patterned into a shape of an ink flow path by a photolithography method or the like. The road pattern 6 can be formed.

  The photosensitive resin used in the present embodiment is not particularly limited, but is preferably a positive photosensitive resin. As the positive photosensitive resin, for example, a polymer main chain decomposition type photosensitive resin mainly composed of polymethylisopropenyl ketone or methacrylic acid ester is used. Examples of the polymer main chain decomposition type positive photosensitive resin mainly composed of methacrylate ester include homopolymers such as polymethyl methacrylate and polyethyl methacrylate, methyl methacrylate and methacrylic acid, acrylic acid, and glycidyl methacrylate. Alternatively, a copolymer with phenyl methacrylate or the like can be given. The photosensitive wavelength of these polymer main chain decomposition-type positive photosensitive resins mainly composed of methacrylic acid ester is generally around 200 to 240 nm. Polymethylisopropenyl ketone has a photosensitive wavelength in the vicinity of 260 to 320 nm.

  The positive photosensitive resin layer can be formed in a desired pattern by exposing the material at an optimal exposure wavelength.

  Next, as shown in FIG. 2C, a photosensitive resin capable of controlling absorbance is coated on the flow path pattern 6 to form a resin layer. In this embodiment, a negative resist containing a thermochromic material (thermochromic material) is covered to form the resin layer 7. Since a discharge port is formed in the resin layer 7 in a later step, examples of the negative resist for forming the resin layer 7 include a negative resist using a radical polymerization reaction and a negative resist using a cationic polymerization reaction. The

  In negative resists using radical polymerization, radicals generated from the photopolymerization initiator contained in the resist cause polymerization and crosslinking between the radically polymerizable monomers and prepolymers contained in the resist. It hardens. Examples of the photopolymerization initiator include benzoins, benzophenones, thioxanthones, anthraquinones, acylphosphine oxides, titanocenes, acridines, and the like. As the monomer capable of radical polymerization, monomers having acryloyl group, methacryloyl group, acrylamide group, maleic diester, allyl group, prepolymer, and the like are suitable, but not limited thereto.

  In negative resists using cationic polymerization, cations generated from the photocation initiator contained in the resist cause polymerization and cross-linking between the cationically polymerizable monomers and prepolymers contained in the resist. It hardens. Examples of the photocation initiator include aromatic iodonium salts and aromatic sulfonium salts. As the monomer or prepolymer capable of cationic polymerization, monomers or prepolymers having an epoxy group, a vinyl ether group or an oxetane group are suitable, but are not limited thereto.

  Moreover, a negative resist may be used individually by 1 type, and 2 or more types may be mixed and used for it. Furthermore, an additive etc. can be added suitably as needed. In addition, as a negative photoresist, “SU-8 series”, “KMPR-1000” (trade name) manufactured by Kayaku Microchem Co., Ltd., “TMMR S2000”, “TMMF S2000” (product) manufactured by Tokyo Ohka Kogyo Name) etc. can also be used.

  Examples of the photosensitive resin capable of controlling the absorbance include a photosensitive resin containing a chromic material. The chromic material only needs to be capable of reversible change in absorbance, and examples thereof include, but are not limited to, thermochromic materials, electrochromic materials, photochromic materials, piezochromic materials, and gas chromic materials. Moreover, as shown in this embodiment, it is preferable that it is a thermochromic material.

  Thermochromic materials are materials that have the property of changing color when heated. Examples of thermochromic materials include, specifically, ethylenediamine derivative metal complexes, tetrahalogeno metal complexes, fluorans, phenylphthalides, indolylphthalides, spiropyrans, leucooramines, acyl or allylolamines. However, it is not limited to this. Moreover, a thermochromic material may be used individually by 1 type, and 2 or more types may be mixed and used for it. Furthermore, you may add suitably additives, such as a color developer, a temperature regulator, and a sensitizer, to a thermochromic material as needed. Further, the thermochromic material may be added directly to the negative resist, or a material encapsulated in microcapsules produced by a known method such as an interfacial polymerization method or a coacervation method may be added. The optimal mixing ratio of thermochromic materials varies depending on the material, but it is high within the range that does not affect the resist characteristics before changing the absorbance and within the range where the absorbance after changing the absorbance is not sensitive. Is preferred. Content in the negative resist (photosensitive resin) of a thermochromic material is 0.001-30 mass%, for example, and it is preferable that it is 0.01-20 mass%. Alternatively, the thermochromic material is preferably contained in the negative resist so that the absorbance of the resist after changing the absorbance is 1 or more in terms of a film thickness of 5 μm.

  Further, the method of coating the negative resist on the flow path pattern 6 is not particularly limited, and for example, a spin coating method, a laminating method, a spray coating method, or the like can be appropriately selected.

  The film thickness of the resin layer 7 is preferably 5 to 100 μm, although it depends on the type of resin used and the amount of liquid droplets discharged from the liquid discharge head.

  Next, as shown in FIG. 2D, a translucent member having a flat surface is pressed against the surface of the resin layer to flatten the surface of the resin layer. In the present embodiment, the surface of the resin layer 7 is flattened by pressing the surface of the resin layer 7 with the plate-like translucent member 8 in the direction from the surface of the resin layer 7 toward the substrate 1.

  As the translucent member 8, for example, glass, quartz, resin, or the like that has been mirror-finished by polishing can be used. However, the material of the translucent member 8 is not limited to this, and any material that transmits light necessary to cure the resin layer 7 may be used.

  Moreover, in order to improve the fluidity | liquidity of the resin layer 7, before a surface of the resin layer 7 is planarized by the flat surface of the translucent member 8, a board | substrate, a resin layer, or a translucent member is heated. Also good. The heating temperature is preferably 50 ° C. to 200 ° C., although it depends on the type of resin used for the resin layer 7.

  In addition, if air is sandwiched between the resin layer 7 and the translucent member, the resin may flow due to the air and cause defects. It is also useful to press the sex member 8.

  Moreover, as a method of pressing the translucent member 8, for example, the translucent member is placed on the surface of the resin layer 7 and pressed from above and below using a press device, but is not limited thereto.

  Next, as shown in FIG. 2E, the absorbance of the resin layer is partially increased. In the present embodiment, the absorbance of a part of the resin layer 7 is increased by heating a part of the resin layer 7 through the flow path pattern 6 using the energy generating element. That is, the resin layer portion 7b around the energy generating element is heated by the energy generating element to increase the absorbance of the resin layer portion 7b.

  The heating temperature can be appropriately selected according to the temperature required for the color change of the thermochromic material, and is, for example, 40 ° C to 200 ° C. The heating time can be appropriately selected according to the time required for the color change of the thermochromic material, and is, for example, 1 to 20 seconds.

  The region of the resin layer portion 7b that is heated to increase the absorbance can be controlled by the amount of heat applied from the energy generating element, and the resin layer portion 7b is formed so as to include at least a region where a discharge port is formed in a subsequent process. The

  Next, as shown in FIG. 2 (f), the resin layer is exposed to light through a translucent member to form a cured portion and an uncured portion in the resin layer. Here, an uncured portion is formed in the resin layer portion where the absorbance has increased. In the present embodiment, the exposure process is performed on the resin layer 7 including the resin layer portion 7 b through the translucent member 8. That is, the resin layer 7 is exposed to light through the translucent member 8 while the translucent member 8 is in contact with the resin layer 7.

  The type of exposure light source is not particularly limited as long as the resin layer 7 can be cured. For example, the exposure light includes ultraviolet rays, visible rays, infrared rays, X-rays, gamma rays and the like. Among these, ultraviolet rays are preferably used. Also, the exposure amount is not particularly limited as long as the exposure amount can cure the resin layer 7.

  In the exposed resin layer 7, the regions other than the resin layer portion 7b having high absorbance absorb the exposure energy to generate a reaction point of the polymerization reaction, and the polymerization reaction proceeds, so that the resin layer becomes insoluble in the developer (resin Layer 7c). On the other hand, the resin layer portion 7b having a high absorbance near the energy generating element does not transmit the exposure energy, so that no reaction point of the polymerization reaction occurs, and the resin layer portion 7b remains soluble in the developer.

  Next, as shown in FIG. 2G, the absorbance of the resin layer portion 7b having a high absorbance is decreased by cooling. For example, by cooling the substrate 1 and the translucent member 8, the absorbance of the resin layer portion 7b can be reduced. The cooling temperature should just be less than temperature required for the color change of a thermochromic material, for example, is 25-100 degreeC.

  Thereafter, the translucent member 8 is removed. The translucent member 8 may be removed before the resin layer portion 7b is cooled.

  In order to prevent a part of the resin layer from adhering to the translucent member 8 when the translucent member 8 is removed, a release material such as a release material is applied to the surface of the translucent member 8 or the resin layer 7. Mold processing may be performed.

  Next, as shown in FIG. 2H, discharge ports are formed in the resin layer portion 7b. Thereafter, an ink supply port (not shown) is formed, and the liquid discharge head can be manufactured by removing the flow path pattern 6 serving as an ink flow path.

(Embodiment 2)
3A to 3H are flowcharts showing the steps of the method of manufacturing the liquid discharge head in the present embodiment. The liquid discharge head of FIG. 1 is moved in the direction perpendicular to the substrate surface along the broken line AA ′. A part of a cross section in each step when cut is shown.

  As shown in FIGS. 3A and 3B, a flow path pattern 6 serving as an ink flow path mold is formed on the substrate 1 having the energy generating element 2 in the same manner as in the first embodiment.

  Next, as shown in FIG. 3C, a negative resist containing an electrochromic material is coated on the flow path pattern 6 to form a resin layer 9. Similarly to the first embodiment, the resin layer 9 includes a negative resist using a radical polymerization reaction and a negative resist using a cation polymerization reaction in order to form a discharge port in a later process.

  In addition, an electrochromic material is a material having a characteristic that a color changes when a voltage is applied. Specific examples of the electrochromic material include N, N′-disubstituted-4,4′-bipyridinium (common name viologen) compounds, polythiophene compounds, polypyrrole compounds, polyanilines, and the like. However, it is not limited to this. Further, the electrochromic materials may be used alone or in combination of two or more. Furthermore, you may add suitably additives, such as a color developer and a sensitizer, to an electrochromic material as needed. Moreover, these electrochromic materials may be added directly to the negative resist, or those encapsulated in microcapsules produced by a known method such as an interfacial polymerization method or a coacervation method may be added. Also, the optimal electrochromic mixing ratio varies depending on the material, but the higher one is within the range that does not affect the resist properties before changing the absorbance and the range after which the absorbance after changing the absorbance is not sensitive. Is preferred. Content in the negative resist (photosensitive resin) of an electrochromic material is 0.001-30 mass%, for example, and it is preferable that it is 0.01-20 mass%. Alternatively, the electrochromic material is preferably contained in the negative resist (photosensitive resin) so that the absorbance of the resist after changing the absorbance is 1 or more in terms of a film thickness of 5 μm.

  The film thickness of the resin layer 9 is preferably 5 to 100 μm, although it depends on the type of resin used and the amount of liquid droplets discharged from the liquid discharge head.

  Next, as shown in FIG. 3 (d), the surface of the resin layer 9 is covered with a plate-like translucent member 8 having a transparent electrode 10 formed on the surface in a direction from the surface of the resin layer 9 toward the substrate 1. By pressing, the surface of the resin layer 9 is flattened. Further, the surface of the resin layer 9 is pressed with the flat surface on the side where the transparent electrode 10 is formed.

  As the translucent member 8, for example, glass, quartz, resin, or the like that has been mirror-finished by polishing can be used. However, the material of the translucent member 8 is not limited to this, and any material that transmits light used to cure the resin layer 9 may be used. As the transparent electrode 10 formed on the surface of the translucent member 8, for example, indium oxide, indium zinc oxide, indium gallium zinc oxide, or the like can be used. However, the transparent electrode 10 is not limited to this, and any material that transmits light used for curing the resin layer 9 may be used. As a method for forming the transparent electrode 10, a known method such as a sputtering method or a method of baking after applying an ink in which metal fine particles are dispersed in a solvent can be used.

  In addition, before or at the same time as the surface of the resin layer 7 is flattened by the translucent member 8, the substrate, the resin layer, or the translucent member may be heated in order to improve the fluidity of the resin layer 9. The heating temperature is preferably 50 ° C. to 200 ° C., although it depends on the type of resin used for the resin layer 7.

  In addition, when air is sandwiched between the resin layer 9 and the translucent member, the resin may flow due to the air and cause defects. It is also useful to press the sex member 8.

  Moreover, as a method of pressing the translucent member, for example, the translucent member can be placed on the upper surface of the resin layer 9 and pressed from above and below using a press device, but is not limited thereto.

  Next, as shown in FIG. 3 (e), by applying a voltage between the transparent electrode 10 and the energy generating element 2, a resin layer portion 9 b having a higher absorbance in the resin layer 9 is formed. That is, by applying a voltage between the transparent electrode 10 and the energy generating element 2, the absorbance of the resin layer portion 9b around the energy generating element is increased.

  The applied voltage can be appropriately selected according to the voltage required for the color change of the electrochromic material, and is, for example, 0.01V to 20V. Further, the applied voltage can be maintained until a reverse voltage is applied in a later step depending on the electromaterial. The application time can be appropriately selected according to the time required for the color change of the electrochromic material, and is, for example, 1 to 20 seconds.

  Although not shown in FIGS. 3 (e) and 3 (g), the transparent electrode 10 and the energy generating element 2 are provided with electrical connections such as wiring for applying a voltage and a power source. More specifically, a wiring and a power source for applying a voltage to the energy generating element 2 are provided on the substrate, and the translucent member 8 is provided with a wiring and a power source for applying a voltage to the transparent electrode 10. The region of the resin layer portion 9b can be controlled by the voltage applied to the transparent electrode 10 and the energy generating element 2, and the resin layer portion 9b is formed so as to include at least a region where a discharge port is formed in a subsequent process.

  Next, as shown in FIG. 3 (f), the resin layer 9 including the resin layer portion 9 b is exposed through the translucent member 8 having the transparent electrode 10. That is, the resin layer 9 is exposed through the translucent member 8 having the transparent electrode 10.

  The type of exposure light source is not particularly limited as long as the resin layer 9 can be cured. For example, the exposure light includes ultraviolet rays, visible rays, infrared rays, X-rays, gamma rays and the like. Among these, ultraviolet rays are preferably used. Also, the exposure amount is not particularly limited as long as the exposure amount can cure the resin layer 9.

  In the exposed resin layer 9, the regions other than the resin layer portion 9b having high absorbance absorb the energy of exposure to generate a reaction point of the polymerization reaction, and the polymerization reaction proceeds, so that it becomes insoluble in the developer (resin Layer 9c). On the other hand, the resin layer portion 9b having a high absorbance does not transmit the exposure energy, so that no reaction point of the polymerization reaction occurs, and the resin layer portion 9b is maintained in a soluble state in the developer.

  Next, as shown in FIG. 3 (g), by applying a voltage opposite to the step shown in FIG. 3 (e) (voltage having the opposite potential) between the transparent electrode 10 and the energy generating element 2. Then, the absorbance of the resin layer portion 9b having increased absorbance is decreased.

  Thereafter, the translucent member 8 on which the transparent electrode 10 is formed is removed from the resin layer. In addition, you may remove the translucent member 8 before reducing the light absorbency of the resin layer part 9b.

  In order to prevent a part of the resin layer from adhering to the translucent member when the translucent member is removed, a release material such as a release material is applied to the surface of the translucent member 8 or the surface of the resin layer 9. Mold processing may be performed.

  Next, as shown in FIG. 3H, a discharge port is formed in the resin layer portion 9b. Thereafter, an ink supply port (not shown) is formed and the flow path pattern 6 is removed, whereby a liquid discharge head can be manufactured.

"Example 1"
In this example, an ink jet recording head was manufactured according to the steps shown in FIGS.

  First, as shown in FIG. 2A, a substrate 1 having an energy generating element on the surface (also referred to as a first surface) was prepared.

  In general, since a driver, a logic circuit, and the like that control the energy generating element 2 are manufactured by a general-purpose semiconductor manufacturing method, it is preferable to apply silicon to the substrate. In this example, a silicon substrate having an energy generating element on an 8-inch silicon substrate was prepared.

  Next, as shown in FIG. 2B, a flow path pattern 6 was formed on the first surface of the substrate 1 using a positive resist made of a photo-disintegrating positive resist.

As the positive resist, a photodegradable positive resist is used, and polymethylisopropenyl ketone (manufactured by Tokyo Ohka Kogyo Co., Ltd., ODUR-1010 (trade name)) is used so that the resin concentration becomes 20% by mass. Prepared. This positive resist is applied onto a substrate by a spin coating method, and then prebaked on a hot plate at 120 ° C. for 3 minutes and then in an oven purged with nitrogen at 150 ° C. for 30 minutes, and a film thickness of 5 μm. A positive resist layer was formed. Then, Deep-UV light with a dose of 18000 mJ / cm ² is passed through the mask on which the flow path pattern is drawn, using a Deep-UV exposure device UX-3000 (trade name) manufactured by USHIO ELECTRIC CO., LTD. Was irradiated. Thereafter, a development treatment is performed with a solution of methyl isobutyl ketone (MIBK) / xylene (Xylene) = 2/3, which is a nonpolar solvent, and a rinse treatment is performed using xylene (Xylene). Pattern 6 was formed.

  Next, as shown in FIG. 2C, a photocurable resin containing a thermochromic material was coated on the flow path pattern 6 to form a resin layer 7. As the photocurable resin, a resist solution having the following composition was used.

EHPE (manufactured by Daicel Chemical Industries) 100 parts by mass SP-172 (manufactured by Adeka) 5 parts by mass A-187 (manufactured by Toray Dow Corning) 5 parts by mass N, N-diethylethylenediamine nickel complex 5 parts by mass Methyl isobutyl ketone 100 parts by mass A photocurable resin having the above composition is applied onto a substrate and a flow path pattern by a spin coat method, prebaked at 90 ° C. for 3 minutes on a hot plate, and made of a 10 μm (on the substrate) negative resist. Layer 7 was formed.

  Next, as shown in FIG. 2 (d), a translucent member 8 having translucency is used in a direction from the surface of the resin layer 7 toward the substrate 1 using a press device ST-50 (manufactured by Toshiba Machine Co., Ltd.). And pressed in a vacuum chamber. Moreover, when pressing the translucent member 8, the resin layer 7 was heated. As the translucent member, a material obtained by depositing Durasurf (manufactured by Daikin) on a quartz substrate polished by Iiyama Special Glass Co., Ltd. with high precision was used.

  Next, as shown in FIG. 2 (e), the energy generating element was heated, and the light-curing resin part (resin layer part 7b) around the energy generating element was discolored to increase the absorbance of this part. At this time, since the temperature of the photo-curing resin closer to the energy generating element is higher, the absorbance of the resin layer portion 7b around the energy generating element is higher.

Next, as shown in FIG. 2 (f), the entire surface was exposed at an exposure amount of 3000 mJ / cm ² using a mask aligner MPA600FA (manufactured by Canon). Next, PEB was performed at 90 ° C. for 180 seconds to cure the resin layer 7 other than the resin layer portion 7b. At this time, in the resin layer portion 7b having increased absorbance, decomposition of SP-172 was inhibited, so that an uncured portion was formed.

  Next, as shown in FIG. 2G, the substrate 1 was cooled, and the absorbance of the resin layer portion 7b, which had been high, was lowered. Furthermore, the pressed translucent member 8 was released.

Next, using a mask aligner MPA600FA (manufactured by Canon), the resin layer 7 was pattern-exposed with an exposure amount of 3000 mJ / cm ² through the mask 20 on which the ink discharge port pattern was drawn. Here, the exposure process was performed so that the ink discharge port pattern was included in the resin layer portion 7b. Next, PEB was performed at 90 ° C. for 180 seconds and cured.

  Next, development processing was performed using a methyl isobutyl ketone / xylene = 2/3 solution, and rinsing processing was performed using xylene, whereby the ink discharge ports 4 were formed.

  Next, an ink supply port (not shown) was formed by etching from the back surface (surface opposite to the first surface) side of the substrate 1. At this time, a substrate having a protective layer and a positive resist on which a slit-like etching mask layer is formed is immersed in an aqueous solution of tetramethylammonium hydroxide at 80 ° C. Etching was performed to form an ink supply port.

Next, after removing the protective layer, the entire surface was exposed with an exposure amount of 7000 mJ / cm ² using a Deep-UV exposure device UX-3000 (trade name) manufactured by USHIO ELECTRIC CO., LTD. Then, the substrate was immersed in methyl lactate while applying ultrasonic waves, thereby removing the flow path pattern and producing an ink jet recording head.

  The ink jet recording head produced by the above method had a uniform shape in which the distance between each energy generating element 2 of the substrate 1 and the discharge port 4 was 1 μm or less at any nozzle. When this ink jet recording head was mounted on a printer and ejection and recording evaluation were performed, it was possible to fly droplets with a stable ejection amount, and the obtained printed matter was of high quality.

"Example 2"
In this example, an ink jet recording head was manufactured according to the steps shown in FIGS.

  First, a substrate 1 as shown in FIG. 2A was prepared in the same manner as in Example 1 (FIG. 3A).

  Next, as shown in FIG. 3B, the flow path pattern 6 was formed on the substrate 1 in the same process as in Example 1.

  Next, as shown in FIG. 3C, a photocurable resin containing an electrochromic material was coated on the flow path pattern to form a resin layer 9. As the photocurable resin, a resist solution having the following composition was used.

EHPE (manufactured by Daicel Chemical Industries) 100 parts by mass SP-172 (manufactured by Adeka) 5 parts by mass A-187 (manufactured by Toray Dow Corning) 5 parts by mass 1,1′-dimethyl-4,4′-bipyridinium dichloride 5 parts by mass 100 parts by mass of methyl isobutyl ketone A photocurable resin having the above composition was applied onto a substrate and a flow path pattern by a spin coating method, and prebaked at 90 ° C. for 3 minutes on a hot plate to obtain 10 μm (on the substrate). A resin layer 9 made of a negative resist was formed.

  Next, as shown in FIG. 3D, a plate-like light-transmitting property having an ITO electrode 10 and wiring (not shown) connected to the electrode 10 on the surface in a direction from the surface of the resin layer 9 toward the substrate 1. The member 8 was pressed in a vacuum chamber using a press apparatus ST-50 (manufactured by Toshiba Machine Co., Ltd.). Moreover, when pressing the translucent member 8, the resin layer 9 was heated. As the translucent member, an ITO film was formed on a quartz substrate polished by Iiyama Special Glass Co., Ltd. with high precision, and Durasurf (manufactured by Daikin) was further formed on the surface of the ITO electrode.

  Next, as shown in FIG. 3E, a voltage of 2.5 V is applied between the energy generating element and the ITO electrode to apply a photo-curing resin portion (resin layer portion 9b) around the energy generating element. By changing the color, the absorbance of this portion was increased. At this time, since the voltage of the photo-curing resin closer to the energy generating element becomes higher, the absorbance of the resin layer portion 9b around the energy generating element becomes higher.

Next, as shown in FIG. 3F, the entire surface was exposed at an exposure amount of 3000 mJ / cm ² using a mask aligner MPA600FA (manufactured by Canon). Next, PEB was performed at 90 ° C. for 180 seconds to cure the resin layer 9 other than the resin layer portion 9b. At this time, since the resin layer portion 9b having increased absorbance was inhibited from decomposing SP-172, the uncured state was maintained.

  Next, as shown in FIG. 3G, a voltage of −2.5 V (a voltage opposite to the previous step) is applied between the energy generating element and the ITO electrode, and the absorbance of the resin layer portion 9b that has been increased is measured. Lowered. Further, the pressed translucent member was released.

  Thereafter, an ink jet recording head was manufactured in the same process as in Example 1. The ink jet recording head produced by the above method had a uniform shape in which the distance between each energy generating element 2 of the substrate 1 and the discharge port 4 was 1 μm or less at any nozzle. When this ink jet recording head was mounted on a printer and ejection and recording evaluation were performed, it was possible to fly droplets with a stable ejection amount, and the obtained printed matter was of high quality.

"Comparative example"
A step of forming a cured portion and an uncured portion in the resin layer via a translucent member without including a step of changing the absorbance of the photocurable resin without including the N, N-diethylethylenediamine copper complex in the photocurable resin. An ink jet recording head was produced in the same manner as in Example 1 except that the ink was not contained. As a result, defects were observed in the peeling process and the desired shape could not be obtained as compared with the example in which the light-transmitting member was released after curing other than the vicinity of the energy generating element by the change in absorbance.

1 Substrate 2 Energy generating element 3 Liquid flow path (ink flow path)
4 Discharge port 5 Discharge port member 6 Flow path type pattern 7 Resin layer 7b containing thermochromic material Resin layer portion 7c with high absorbance 8 Cured portion of resin layer 8 Translucent member 9 Contains electrochromic material Resin layer 9b Resin layer portion 9c having increased absorbance Resin layer cured portion 10 Transparent electrode

Claims (9)

A substrate having an energy generating element on the first surface for generating energy for discharging liquid, a discharge port for discharging the liquid, and a flow path forming member for forming a liquid flow path communicating with the discharge port; A method of manufacturing a liquid discharge head having
(1) forming a flow path mold pattern serving as a mold of the liquid flow path on the first surface of the substrate;
(2) A step of coating a photosensitive resin capable of controlling absorbance on the flow path pattern and forming a resin layer;
(3) pressing a translucent member having a flat surface on the surface of the resin layer to flatten the surface of the resin layer;
(4) partially increasing the absorbance of the resin layer;
(5) A step of forming a cured portion and an uncured portion on the resin layer by performing an exposure process on the resin layer through the light transmissive member, and the resin layer portion where the absorbance is increased. An uncured part is formed,
(6) reducing the absorbance of the resin layer portion where the absorbance has increased,
(7) forming the discharge port in the uncured portion;
In this order,
In the steps (4) and (5), the flat surface of the translucent member is brought into contact with the surface of the resin layer.   The method for manufacturing a liquid discharge head according to claim 1, wherein the photosensitive resin contains a chromic material.   The method for manufacturing a liquid discharge head according to claim 2, wherein the wavelength whose absorbance can be controlled by the chromic material includes a wavelength at which the photosensitive resin is exposed.   The method for manufacturing a liquid discharge head according to claim 2, wherein the chromic material is a thermochromic material.   The method of manufacturing a liquid ejection head according to claim 4, wherein in the step (4), the absorbance of the resin layer is partially increased by heating the resin layer using the energy generating element.   The method for manufacturing a liquid discharge head according to claim 2, wherein the chromic material is an electrochromic material. The translucent member has a transparent electrode on the flat surface,
The method of manufacturing a liquid ejection head according to claim 6, wherein in the step (4), the absorbance is partially increased by applying a voltage between the energy generating element and the transparent electrode.   The process according to claim 1, further comprising a step of peeling the translucent member from the resin layer between the step (5) and the step (6) or between the step (6) and the step (7). A method of manufacturing a liquid discharge head according to any one of the above.   The method of manufacturing a liquid ejection head according to claim 1, wherein the exposure process in the step (5) is a whole surface exposure.

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