JP4851272B2 - Nozzle plate manufacturing method - Google Patents

Description

  The present invention relates to a method for manufacturing a nozzle plate, and more particularly to a method for manufacturing a nozzle plate used in a liquid discharge head typified by an inkjet head, a liquid discharge head including the nozzle plate manufactured thereby, and an image forming apparatus.

  An ink jet recording apparatus is a method of recording information on a recording medium by ejecting ink from fine nozzles (liquid ejection ports) of a print head. Therefore, a nozzle plate in which nozzle holes are formed has an ink ejection performance. It is one of the very important parts to decide. The ink ejection performance varies greatly depending on the nozzle hole shape and the like, and high dimensional accuracy is required to make the ejection performance uniform for a large number of nozzle holes.

  In particular, in recent years, in the field of inkjet recording, the need for high speed and high image quality has further increased, and a one-pass recording (recording by one sub-scan feed using a page-wide print head) system using high-viscosity ink has been developed. However, the nozzle part of the head is required to have a thin and wide angle to reduce the flow resistance, and to increase the accuracy and reduce the density unevenness due to printing, multiple nozzles to realize page-wide wide recording And high reliability for stable operation are required.

  Regarding the nozzle plate manufacturing technique, Patent Document 1 discloses a method for forming a metal taper nozzle with a counterbore having a high aspect ratio by performing double-sided exposure from the front and back sides of a conductive transparent substrate.

  Patent Document 2 discloses a method of forming a tapered electroformed nozzle at a time by exposing from the back surface of a transparent substrate coated with a resist.

  Patent Document 3 discloses a method of forming a nozzle having a tapered portion and a straight portion by performing exposure from both sides of a transparent substrate coated with a resist.

Patent Document 4 discloses a technique for forming a “constriction” having a forward tapered portion and a non-forward tapered portion on an orifice plate to improve landing errors of ejected droplets.
JP 7-329304 A Japanese Patent Laid-Open No. 10-296982 JP 2004-330636 A JP 2001-187451 A

  However, in the invention disclosed in Patent Document 1, the tapered portion is formed by using a tilted rotation of the substrate in addition to the diffusion plate. However, it is difficult to control the shape with the diffused light, and shape variation is likely to occur. As a result, the nozzle shape becomes non-uniform, which adversely affects image formation. In addition, even if the taper is formed by tilt exposure, the substrate side opening has an acute angle, which tends to cause a variation in accuracy.As the angle becomes wider, the gap between the light source and the substrate becomes wider, and the illuminance uniformity decreases. There is a problem that the apparatus is also enlarged.

  In the invention disclosed in Patent Document 2, since the taper is naturally formed by parallel light, it is difficult to widen the angle, and the discharge portion is formed by plating growth, so it is difficult to form with high accuracy. It is.

  In the invention disclosed in Patent Document 3, the mask is formed by exposing the mask away from the resist surface. However, it is extremely difficult to control the spread of light by such a method, and a highly accurate nozzle is used. Not suitable for formation.

  In the invention disclosed in Patent Document 4, a taper of about 12 ° is formed by exposure with a relatively large NA (numerical aperture) using a Keller illumination system, but there is a limit to increasing NA. For example, it is difficult to form a wide-angle taper of 20 to 40 ° that is expected to be necessary for high-speed discharge of a high-viscosity liquid having a viscosity of 10 to 20 mPa · s at a high discharge frequency of 20 to 40 kHz. Furthermore, since the orifice plate obtained by the invention disclosed in the document 4 is limited to a resin material, the rigidity, liquid contact property, and scratch resistance are insufficient. Also, when adding a counterbore around the nozzle on the discharge surface side or adding an adhesive escape groove on the opposite side of the discharge surface, these counterbore part and adhesive escape groove are formed simultaneously with the nozzle hole. It is difficult to do and is not suitable for lengthening and large area processing.

This invention is made in view of such a situation, and provides the manufacturing method of the nozzle plate which can produce the desired nozzle shape which has a wide-angle taper part, a constriction part, etc. with high precision. It shall be the purpose.

In order to achieve the above object, in the method of manufacturing a nozzle plate according to claim 1, the transmittance increases as the incident angle of the light of the wavelength increases on one side of the transmission substrate that transmits the light of the wavelength used for exposure. The exposure mask is formed by laminating a light interference layer having the characteristics of the above and a light blocking layer made of a material that does not transmit light of the wavelength, and the negative surface is formed on the surface of the exposure mask on which the light blocking layer is formed. A photosensitive material adhering step for adhering the photosensitive material, and a light having a wavelength relatively smaller than that of the transmissive substrate from the surface on the transmission substrate side of the exposure mask on which the photosensitive material is adhered. The exposure mask on which the photosensitive material is adhered is rotated while irradiating at an incident angle of 1 second, and the second light path formed in the light interference layer and the second light blocking layer are formed. Through the light passage area The photosensitive material is exposed to light incident on the photosensitive material, and the light transmitted through the photosensitive material is reflected on the back side of the photosensitive material, and the reflected material is used to sensitize the photosensitive material. The first exposure step of forming a photosensitive region portion having a first taper shape, and the light of the wavelength from the surface of the exposure mask to which the photosensitive material is adhered on the transmission substrate side. While irradiating at a relatively large second incident angle with respect to the transmission substrate, the exposure mask having the photosensitive material attached thereto is rotated, and the photosensitive material passes through the light interference layer and the second light passage region. The photosensitive material is sensitized by light incident on the photosensitive material, while reflection of light transmitted through the photosensitive material from the back side of the photosensitive material is suppressed, and a second direction opposite to the first tapered shape is obtained. Taper type A second exposure step of forming a photosensitive region portion having, after said first exposure step and said second exposure step, a development step of performing development processing, the photosensitive material pattern remaining by the development And a metal film forming step of forming a metal film corresponding to the nozzle plate using an electroforming method, wherein the first exposure step is performed in a first medium having a first refractive index. The reflected light is used to sensitize the photosensitive material by reflecting the light transmitted through the photosensitive material at the interface between the photosensitive material and the first medium, while the second The exposure step is performed in a second medium having a second refractive index larger than the first refractive index, and the light passing through the photosensitive material and the photosensitive material and the second medium. It is characterized in that reflection at the interface is reduced .

  According to the present invention, the first exposure process (narrow angle tilt rotation exposure) using reflected light from the back side of the photosensitive material and the second exposure process (wide angle tilt) not using reflected light from the back side. In combination with (rotational exposure), a wide-angle tapered photosensitive material pattern having a “necked portion” can be formed with high accuracy by the first tapered shape and the second tapered shape.

  For the light interference layer and the light blocking layer constituting the exposure mask, by forming the first light passage region and the second light passage region with a pattern corresponding to the nozzle shape and nozzle arrangement of the nozzle plate to be created, It is possible to collectively form a photosensitive material pattern corresponding to the shape of the above-described wide-angle tapered nozzle having a constricted portion.

  By using such a photosensitive material pattern, it is possible to produce a nozzle plate in which a large number of wide-angle tapered nozzles having a constricted portion are formed.

  In the nozzle plate manufactured according to the present invention, each nozzle hole has a constricted portion, so the position of the meniscus is stabilized, the influence of the substrate surface is mitigated, and a discharge guide function can be provided, so even a wide-angle taper causes little flight bending Stable high-viscosity high-speed discharge is possible.

As shown in this aspect, by performing rotational exposure while switching the incident angle in a plurality of media having different refractive indexes, the level of the interface reflectance can be switched depending on the refractive index difference of the medium in contact with the photosensitive material. .
Moreover, since the aspect of this invention is a constriction, the adhesiveness of the photosensitive material improves. Moreover, since the nozzle plate obtained by this aspect is metal, a flaw resistance, rigidity, and liquid-contact property improve.

The invention according to claim 2 is an aspect of the method of manufacturing the nozzle plate according to claim 1 , wherein the first medium is a gas and the second medium is a liquid.

  The refractive index of the liquid is close to the refractive index of the photosensitive material, and since the refractive index of gas is smaller than that of the liquid, the interface reflectance between the photosensitive material and the gas is high, and the interface reflectance between the photosensitive material and the liquid is descend. Therefore, the first exposure process and the second exposure process in the present invention can be realized by switching between narrow angle tilt rotation exposure in gas and wide angle tilt rotation exposure in liquid.

  The type of gas or liquid is not particularly limited, but carbon dioxide is preferably used as the first medium because it has a low refractive index of about 1.0 and high solubility. By using carbon dioxide, it is possible to switch the reflectance (liquid replacement) safely and reliably.

  Further, as the second medium, for example, water can be used. The refractive index of water is about 1.3, which is close to the refractive index of a transmissive substrate (for example, quartz glass) and photosensitive material, can suppress the back reflection of the photosensitive material, and has few impurities, thus stabilizing the quality. Can do. The back surface reflectance of the photosensitive material can be switched depending on the presence or absence of an inexpensive liquid such as distilled water or filtered water. Furthermore, by using immersion exposure, it is possible to form a taper having a wider angle than in the air (in the gas), and it is possible to reduce the tilt angle of the tilt rotation stage.

The method according to claim 3 in engagement Ru Roh nozzle plate, on one side of the transparent substrate that transmits light of a wavelength used for the exposure, light having a characteristic in which the transmittance increases as the incident angle of the light with wavelength increases Using an exposure mask in which an interference layer and a light blocking layer made of a material that does not transmit light of the wavelength are laminated, a negative photosensitive material is applied to the surface of the exposure mask on which the light blocking layer is formed. Irradiating light of the wavelength at a first incident angle relatively small with respect to the transmissive substrate from the surface of the transmissive substrate side of the exposure mask to which the photosensitive material is adhered, and a photosensitive material adhesion process to be adhered However, the exposure mask to which the photosensitive material is attached is rotated and passed through the first light passage region formed in the light interference layer and the second light passage region formed in the light blocking layer. Incident on the photosensitive material The photosensitive material is sensitized by the generated light, the light transmitted through the photosensitive material is reflected on the back side of the photosensitive material, and the photosensitive material is exposed to the reflected light, thereby the first A first exposure step for forming a photosensitive region portion having a taper shape, and light having the wavelength relative to the transmission substrate from the surface on the transmission substrate side of the exposure mask to which the photosensitive material is adhered. While irradiating at a large second incident angle, the exposure mask to which the photosensitive material is attached is rotated, and the photosensitive material is irradiated with light incident on the photosensitive material through the light interference layer and the second light passage region. A photosensitive region having a second tapered shape opposite to the first tapered shape, wherein the photosensitive material is exposed to light, and reflection of light transmitted through the photosensitive material from the back side of the photosensitive material is suppressed. Shape A second exposure process, a development process for performing a development process after the first exposure process and the second exposure process, and a photosensitive material pattern remaining after the development process, and using an electroforming method A metal film forming step of forming a metal film corresponding to the nozzle plate, and a reflective member is provided on the back side of the photosensitive material attached to the exposure mask, and the reflective member for the photosensitive material In the first exposure step, the reflecting member is disposed close to the photosensitive material, and the light transmitted through the photosensitive material is reflected by the reflecting member, While the reflected light is used to sensitize the photosensitive material, in the second exposure step, the reflecting member is moved away from the photosensitive material to such an extent that light transmitted through the photosensitive material does not hit the reflecting member. It arrange | positions and suppresses the reflection by the said reflection member, It is characterized by the above-mentioned.

  By switching the position of the reflecting member, it is possible to switch between a first exposure process that uses reflection exposure from the back side of the photosensitive material and a second exposure process that does not use it.

  As shown in this aspect, the configuration using the reflective member can set the reflectance by the reflective member high, and therefore, reliable reflective exposure is possible even with a light source with low illuminance.

The invention according to claim 4 is an aspect of the method for manufacturing a nozzle plate according to claim 3 , wherein the first exposure step and the second exposure step are performed in pure water. .

In particular, the refractive index of deionized pure water is approximately 1.4, which is close to that of a transmissive substrate and a photosensitive material. By performing exposure in pure water, the resist back surface reflection can be more effectively suppressed. A wider-angle taper can be formed than water or filtered water.
A fifth aspect of the present invention is an aspect of the method for manufacturing a nozzle plate according to any one of the first to fourth aspects, wherein the metal film forming step includes a liquid repellent plating process for forming a liquid repellent plated layer. And a Ni electroforming step of depositing nickel (Ni) on the liquid-repellent plating layer.
By subjecting the developed substrate to liquid repellent plating and Ni plating in the manner of overhang electroforming, and polishing the growth surface, a long and highly accurate metal nozzle can be formed. The base may be electroless plating.
The invention according to claim 6 is an aspect of the method for manufacturing a nozzle plate according to claim 5, wherein the light blocking layer is a second semi-transmissive region corresponding to a groove formed on a discharge surface side of the nozzle plate. And a photosensitive region corresponding to the shape of the groove is formed by light transmitted through the second semi-transmissive region in the second exposure step, and the photosensitive material is formed in the Ni electroforming step. A Ni layer is deposited on the photosensitive region corresponding to the shape of the groove of the pattern, thereby forming a groove having a concave surface on the opposite side to the groove.
By growing an isotropic metal film by Ni electroforming, a Ni film also grows on the upper surface of the photosensitive region corresponding to the groove shape, and the upper surface is eventually covered with the Ni film. As a result, a concave shape is formed, and the concave portion functions as an adhesive escape groove or a stress relaxation groove during adhesive bonding with another flow path substrate.
The method of manufacturing a nozzle plate according to claim 7 is characterized in that, on one side surface of a transmission substrate that transmits light having a wavelength used for exposure, an optical interference layer having a characteristic that transmittance increases as the incident angle of light having the wavelength increases. And a light-shielding layer made of a material that does not transmit light of the wavelength, and a positive photosensitive material is attached to the surface of the exposure mask on which the light-shielding layer is formed. While irradiating light of the wavelength from the surface on the transmission substrate side of the exposure mask to which the photosensitive material is adhered with a relatively small first incident angle with respect to the transmission substrate. The exposure mask with the photosensitive material attached is rotated, and the photosensitivity is transmitted through the first light passage region formed in the light interference layer and the second light passage region formed in the light blocking layer. Incident on the conductive material The photosensitive material is sensitized by the generated light, the light transmitted through the photosensitive material is reflected on the back side of the photosensitive material, and the photosensitive material is exposed to the reflected light, thereby the first A first exposure step for forming a photosensitive region portion having a taper shape, and light having the wavelength relative to the transmission substrate from the surface on the transmission substrate side of the exposure mask to which the photosensitive material is adhered. While irradiating at a large second incident angle, the exposure mask to which the photosensitive material is attached is rotated, and the photosensitive material is irradiated with light incident on the photosensitive material through the light interference layer and the second light passage region. A photosensitive region having a second tapered shape opposite to the first tapered shape, wherein the photosensitive material is exposed to light, and reflection of light transmitted through the photosensitive material from the back side of the photosensitive material is suppressed. Shape A second exposure step, a development step for performing a development process after the first exposure step and the second exposure step, and a nozzle plate composed of a photosensitive material remaining by the development process. And the first exposure step is performed in a first medium having a first refractive index, and the light transmitted through the photosensitive material is transferred to the photosensitive material and the first medium. The second exposure step has a second refractive index larger than the first refractive index, while the reflected light is used for the photosensitive material. The reflection of light transmitted through the photosensitive material at the interface between the photosensitive material and the second medium is reduced.
The invention according to claim 8 is the method of manufacturing a nozzle plate according to claim 7, wherein the first medium is a gas and the second medium is a liquid.
The method of manufacturing a nozzle plate according to claim 9 is characterized in that, on one side surface of a transmissive substrate that transmits light having a wavelength used for exposure, an optical interference layer having a characteristic that transmittance increases as the incident angle of light having the wavelength increases. And a light-shielding layer made of a material that does not transmit light of the wavelength, and a positive photosensitive material is attached to the surface of the exposure mask on which the light-shielding layer is formed. While irradiating light of the wavelength from the surface on the transmission substrate side of the exposure mask to which the photosensitive material is adhered with a relatively small first incident angle with respect to the transmission substrate. The exposure mask with the photosensitive material attached is rotated, and the photosensitivity is transmitted through the first light passage region formed in the light interference layer and the second light passage region formed in the light blocking layer. Incident on the conductive material The photosensitive material is sensitized by the generated light, the light transmitted through the photosensitive material is reflected on the back side of the photosensitive material, and the photosensitive material is exposed to the reflected light, thereby the first A first exposure step for forming a photosensitive region portion having a taper shape, and light having the wavelength relative to the transmission substrate from the surface on the transmission substrate side of the exposure mask to which the photosensitive material is adhered. While irradiating at a large second incident angle, the exposure mask to which the photosensitive material is attached is rotated, and the photosensitive material is irradiated with light incident on the photosensitive material through the light interference layer and the second light passage region. A photosensitive region having a second tapered shape opposite to the first tapered shape, wherein the photosensitive material is exposed to light, and reflection of light transmitted through the photosensitive material from the back side of the photosensitive material is suppressed. Shape A second exposure step, a development step for performing a development process after the first exposure step and the second exposure step, and a nozzle plate composed of a photosensitive material remaining by the development process. And a reflective member is provided on the back side of the photosensitive material attached to the exposure mask, and the relative position of the reflective member with respect to the photosensitive material can be changed. In the first exposure step, The reflecting member is arranged close to the photosensitive material, and the light transmitted through the photosensitive material is reflected by the reflecting member, so that the reflected light is used for the photosensitive material. In the second exposure step, the reflection member is disposed away from the photosensitive material so that light transmitted through the photosensitive material does not hit the reflection member, and reflection by the reflection member is suppressed. Features.
As shown in this embodiment, it is possible to manufacture a resin nozzle plate using a positive type photosensitive material.
According to a tenth aspect of the present invention, in the method for manufacturing a nozzle plate according to the ninth aspect, the first exposure step and the second exposure step are performed in pure water.
The invention according to claim 11 is the nozzle plate manufacturing method according to any one of claims 7 to 10, wherein at least an inner surface of the nozzle plate made of the photosensitive material remaining by the development processing is protected. A protective film forming step of attaching a film; and a liquid repellent film forming step of attaching a liquid repellent film to the ejection surface of the nozzle plate peeled from the exposure mask.
A twelfth aspect of the invention is the nozzle plate manufacturing method according to any one of the seventh to eleventh aspects, wherein a nozzle inflow side is disposed on the photosensitive material side of the exposure mask to which the photosensitive material is attached. By disposing a groove forming exposure mask having a third semi-transmissive region narrower than the opening and irradiating the groove forming exposure mask with light, the light transmitted through the third semi-transmissive region Including a third exposure step of exposing the photosensitive material, wherein the photosensitive region portion corresponding to the groove in which the surface on the nozzle inflow side is recessed is formed by the third exposure step. .
When a positive type photosensitive material is used, the adhesive relief groove portion is separately exposed using a groove forming exposure mask. At this time, by making the width of the third semi-transmissive region narrower than the nozzle flow path side opening, an adhesive escape groove having a narrower width than the nozzle inflow side opening can be formed. As a result, the surplus adhesive is absorbed by the narrow adhesive escape groove, so that clogging of the nozzle hole at the time of adhesion can be avoided, and stable adhesion is possible even with a wide-angle taper nozzle.

A thirteenth aspect of the present invention is an aspect of the method for manufacturing a nozzle plate according to any one of the first to twelfth aspects, wherein the light blocking layer surrounds the second light passage region. And a step shape corresponding to the counterbore portion by the light transmitted through the first semi-transmissive region in the second exposure step. The photosensitive region portion is formed.

  According to this aspect, it is possible to form a concave counterbore around the nozzle and at the same time as the taper. Productivity is good because a counterbore shape can be applied simultaneously with nozzle formation. The nozzle plate having such a counterbore portion improves the reliability during jamming and wiping.

The invention according to claim 14 is an aspect of the method for manufacturing a nozzle plate according to any one of claims 1 to 13 , wherein the light blocking layer is formed in a groove formed on a discharge surface side of the nozzle plate. A corresponding second semi-transmissive region, and a light-sensitive region corresponding to the shape of the groove is formed by the light transmitted through the second semi-transmissive region in the second exposure step. Features.

  According to this aspect, the trap groove portion can be formed simultaneously with the counterbore portion. By providing the trap groove on the ejection surface of the nozzle plate, ink contamination on the nozzle surface is reduced, and the wiping performance during cleaning is improved.

A fifteenth aspect of the present invention is an aspect of the nozzle plate manufacturing method according to any one of the first to fourteenth aspects, wherein the exposure mask includes a dummy mask in a region other than the nozzle plate forming portion. A light receiving monitor unit having a pattern is provided, and a light receiving unit for receiving light transmitted through the photosensitive material through the dummy mask pattern on a stage for fixing the exposure mask to which the photosensitive material is attached. A sensor is arranged, and in the second exposure step, out of the light receiving area of the light receiving sensor, the light passing through a dummy light passing area corresponding to the first light passing area is blocked from entering the light receiving sensor. The light-receiving sensor monitors the transmitted light of the photosensitive material, and controls the exposure amount based on the monitoring result.

  According to this aspect, since correction exposure can be performed while monitoring actual transmitted light by the light receiving sensor, optimum exposure can be realized, and stable production with less product variation is possible. In particular, by providing the shielding means, it becomes possible to monitor the wavelength that contributes to the formation of the second tapered shape in the second exposure step, and not only in the first exposure step but also in the second exposure step, It is possible to perform the exposure under optimum conditions in which the transmittance variation of the transmissive substrate and the photosensitive material is corrected.

The invention according to claim 16 is an aspect of the method of manufacturing a nozzle plate according to any one of claims 1 to 15 , and as a light source used in the first exposure step and the second exposure step, A discharge lamp is used, and in the light source spectrum of the discharge lamp, in the second exposure step, light having a wavelength longer than the wavelength contributing to the formation of the second tapered photosensitive region portion is removed. The exposure mask is irradiated during the first exposure step and the second exposure step.

  Such an embodiment improves the light source utilization efficiency compared to an embodiment in which a single wavelength transmission filter is combined with a discharge lamp. As the discharge lamp, a high pressure mercury lamp, an ultra high pressure mercury lamp, a mercury xenon lamp, or the like is desirable.

The invention according to claim 17 relates to an aspect of the nozzle plate manufacturing method according to any one of claims 1 to 16 , wherein the exposure mask includes nozzle plate formation regions corresponding to a plurality of nozzle plates. The mask pattern is arranged in rotational symmetry.

  In view of the symmetry of rotational exposure, a mode in which mask patterns in units of nozzle plates are arranged rotationally symmetrically on the transmission substrate and the formed nozzle plates are managed for each symmetrical position is preferable.

  For example, if a nozzle plate at a symmetrical position is used in the same apparatus, it is easy to align the characteristics of the nozzle plate (such as flying bend and discharge deposition), and a correction value can be shared.

According to another aspect of the present invention, there is provided a liquid discharge head including a nozzle plate manufactured by the method for manufacturing a nozzle plate according to any one of claims 1 to 17 .

According to another aspect of the present invention, there is provided an image forming apparatus having the above-described liquid discharge head.

An ink jet recording apparatus as one aspect of the image forming apparatus includes a nozzle (discharge port) for discharging ink droplets for forming dots and a pressure generating element (piezoelectric actuator) for generating discharge pressure. A liquid discharge head (recording head) in which a large number of droplet discharge elements (ink liquid chamber units) are arranged at high density is provided, and from the liquid discharge head based on ink discharge data (dot image data) generated from an input image. And an ejection control means for controlling ejection of the liquid droplets, and an image is formed on the recording medium by the liquid droplets ejected from the nozzles.

  For example, color conversion and halftoning processing are performed based on image data (print data) input via the image input means, and ink ejection data corresponding to the ink color is generated. Based on this ink ejection data, the drive of the pressure generating element corresponding to each nozzle of the liquid ejection head is controlled, and an ink droplet is ejected from the nozzle.

  In order to realize high-resolution image output, a droplet discharge element (ink chamber unit) including a nozzle (discharge port) for discharging an ink liquid, a pressure chamber corresponding to the nozzle, and a pressure generation element ) Is preferably used in a liquid discharge head in which a large number of nozzles are arranged at high density.

  As a configuration example of such a liquid discharge head for printing, a full line type head having a nozzle row in which a plurality of discharge ports (nozzles) are arranged over a length corresponding to the entire width of the recording medium can be used. In this case, a combination of a plurality of relatively short ejection head modules having a nozzle row less than the length corresponding to the entire width of the recording medium, and connecting them together, the nozzle having a length corresponding to the entire width of the recording medium as a whole There is an aspect that constitutes a column.

  A full-line type head is usually arranged along a direction perpendicular to the relative feeding direction (relative conveyance direction) of the recording medium, but has a certain angle with respect to the direction perpendicular to the conveyance direction. There may be a mode in which the head is arranged along the oblique direction.

  “Recording medium” is a medium (which can be referred to as a printing medium, an image forming medium, a recording medium, an image receiving medium, a discharged medium, or the like) that receives adhesion of ink discharged from the discharge port of the liquid discharge head. Various media are included regardless of material or shape, such as continuous paper, cut paper, sealing paper, resin sheets such as OHP sheets, printed boards on which films, cloths, wiring patterns, etc. are formed.

  The transporting means for moving the recording medium and the liquid discharge head relative to each other includes a mode for transporting the recording medium to the stopped (fixed) head, a mode for moving the head relative to the stopped recording medium, or a head And a mode in which both the recording medium and the recording medium are moved. When a color image is formed using an inkjet print head, a print head may be arranged for each of a plurality of colors of ink (recording liquid), or a plurality of colors of ink are ejected from one print head. It is good also as a possible structure.

  According to the present invention, a large number of wide-angle taper nozzles having a constricted portion can be collectively formed with high accuracy. According to the liquid discharge head using the nozzle plate obtained by the present invention, high-speed discharge of a high viscosity liquid can be realized.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[Configuration example of tilt rotation type exposure apparatus]
First, an outline of a configuration example of an inclined rotation type exposure apparatus used in a nozzle plate manufacturing method according to an embodiment of the present invention will be described.

  FIG. 1 is a block diagram showing an example of an exposure apparatus. The exposure apparatus 10 is mainly composed of a light source 12, an irradiation optical system 14, an immersion container 16, a transmission correction plate 18, and a stage 20, and the light emitted from the light source 12 is collimated downward in the figure by the irradiation optical system 14. The resist (photosensitive material) 24 on the back surface of the mask is exposed to light by irradiating the exposure mask 22 on the stage 20 which is inclined and rotated.

  The stage 20 is disposed in the immersion container 16. The stage 20 introduces a liquid (for example, pure water) into the immersion container 16 to perform exposure in the liquid, and performs exposure in the gas. It is possible to switch between normal (dry) exposure.

  Further, the stage 20 has a rotation mechanism capable of rotating the table surface 26 in-plane, and an inclination (oscillation) capable of adjusting an inclination angle of the table surface 26 (an inclination angle with respect to a horizontal plane, that is, an incident angle of irradiation light). And a tilt rotation stage equipped with a mechanism.

  That is, the stage 20 is attached to a rotary shaft 28 perpendicular to the table surface 26 and can be rotated around the rotary shaft (first rotary shaft) 28. Further, the rotary shaft 28 of the stage 20 is a mechanism that can swing in a vertical plane orthogonal to the table surface 26, and the tilt angle of the table surface 26 can be varied by the swing position of the rotary shaft 28. Further, the tiltable rotation shaft 28, the stage 20, and the entire liquid immersion container 16 are rotatable in a horizontal plane around a rotation shaft 30 parallel to the vertical line. The specific structure of the mechanism for tilting and rotating the stage 20 will be described later.

  FIG. 2 is an enlarged view of the exposure unit. As shown in the drawing, the exposure mask 22 corresponds to a light interference film (corresponding to “light interference layer”) 34 on the back side of a transparent substrate (corresponding to “transmission substrate”) 32 and an opaque film (corresponding to “light blocking layer”). ) 36 and a resist 24 is applied to the back surface of the exposure mask 22.

  The optical interference film 34 is composed of a dielectric multilayer film in which a high refractive index material and a low refractive index material are alternately laminated, and an opening region (“first” for realizing desired exposure to the resist 24. (Corresponding to “one light passage region”) and the like. A desired transmittance can be obtained for a predetermined wavelength by adjusting the film thicknesses of the high refractive index material and the low refractive index material to be laminated. The optical interference film 34 has an incident angle dependency in which the transmittance varies depending on the incident angle of light. Although details will be described later, the incident angle dependency of the transmittance is used to make the resist 24 The photosensitive area is controlled.

  The opaque film 36 is made of, for example, chromium (Cr) or chromium oxide, and is formed by a method such as sputtering or vacuum deposition. The opaque film 36 also has an opening region (corresponding to a “second light passage region”) 40 and a semi-transparent region (corresponding to a “first semi-transmissive region”) 42 for realizing desired exposure to the resist 24. Are formed in a predetermined pattern.

  The resist 24 is attached to the back side of the exposure mask 22 (the side on which the interference film 34 and the opaque film 36 are laminated) with an appropriate thickness corresponding to the thickness of the nozzle plate that is the production target. As a method of attaching the resist 24, there are an aspect in which application by a spin coater or the like or a dry film (DFR) is used.

  A concave portion 44 is formed in the table surface 26 of the stage 20 so that a gap 43 is formed on the back side of the layer of the resist 24 in a state where the exposure mask 22 with the resist is fixed on the stage 20. At the time of dry exposure, the gap 43 is filled with gas to form a gas layer (reference numeral 106 in FIG. 11). On the other hand, at the time of immersion exposure, the gap 43 is filled with a liquid to form a liquid layer (reference numeral 108 in FIG. 11).

  Generally, the refractive index of the resist 24 is about 1.6, the refractive index of ambient gas (air or carbon dioxide) at the time of dry exposure is 1, and the refractive index of the liquid (for example, pure water) introduced at the time of immersion exposure is Since the refractive index of the liquid dedicated for immersion is about 1.6, and the refractive index of glass (for example, quartz glass) as the transparent substrate 32 is 1.47, the back reflection of the resist 24 is It is large in the gas (interface with the gas layer) and small in the liquid (interface with the liquid layer).

The reflectance of light at the medium interface having the refractive indexes n ₁ and n ₂ is expressed by the following equation in the case of substantially normal incidence.

{(N ₂ −n ₁ ) / (n ₂ + n ₁ )} ²
The interface reflectance when traveling from the resist 24 to the air is about 5%, and the interface reflectance when traveling from the resist 24 to the water is 0.5% or less.

  In the present embodiment, based on the above principle, an exposure process for performing resist exposure by actively utilizing resist back surface reflection in gas, and an exposure process for performing resist exposure by suppressing resist back surface reflection in liquid. By combining, a reverse taper resist (drum-shaped resist) having a constricted portion corresponding to the nozzle shape is collectively formed.

  Although the detailed process will be described later, if oblique incident light and resist back surface reflection are used in the gas, the transmission range of light incident from the exposure mask 22 side and the light reflected from the back surface of the resist return into the resist 24. Depending on the passing range, the resist 24 in a range of an inverted frustoconical shape (a frustoconical shape having a large upper surface and a small lower surface) can be exposed (corresponding to a “photosensitive region portion having a first tapered shape”). At this time, since the antireflection film (AR film) 46 is formed on the surface of the stage 20 (the floor surface of the recess 44) facing the lower surface of the resist 24 with the gap 43 interposed therebetween, the reflected light from the stage surface Return is prevented.

  On the other hand, when exposure is performed in a liquid (during liquid immersion exposure) and the back surface reflection of the resist 24 (reflection at the interface with the liquid layer of the gap portion 43) is suppressed, resist exposure by the back surface reflected light is suppressed. The resist 24 in a frustoconical range corresponding to the incident angle of the light can be exposed to light incident from the exposure mask 22 side (corresponding to a “photosensitive region portion having a second tapered shape”). ). Therefore, by performing the dry exposure process using the resist back surface reflection and the liquid immersion exposure process not using the resist back surface reflection, it is possible to produce the hourglass shape in which the inverted truncated cone shape and the truncated cone shape are combined. .

  When exposure is performed in a gas (during dry exposure), since the periphery of the exposure mask 22 is in contact with the gas (medium having a refractive index of approximately 1), the upper limit of the incident angle is about 38 degrees due to total reflection. On the other hand, when exposure is performed in a liquid (during immersion exposure), the refractive index of the transparent substrate 32 of the exposure mask 22 (about 1.47 in the case of quartz glass) and the refractive index of the surrounding environment (pure In the case of water, approximately 1.44) can be approximated, so that the upper limit of the incident angle due to total reflection is larger than that during dry exposure. For this reason, tilt exposure in a liquid is suitable for forming a wide-angle taper.

  As shown in FIG. 2, a light receiving sensor 48 capable of receiving light transmitted through the resist 24 is embedded in the stage 20, and the exposure amount (that is, the transmitted light is monitored by the light receiving sensor 48 (that is, The irradiation time of light, irradiation intensity, or a combination thereof is controlled.

  FIG. 3 is a plan view showing an arrangement example of the light receiving sensor 48. FIG. 3 shows an example in which four nozzle plate forming portions 50 are provided on the transparent substrate 32. Each nozzle plate forming portion 50 has a number corresponding to the nozzle arrangement of the nozzle plate to be manufactured. A mask pattern including the opening regions 38 and 40 (see FIG. 2) is formed.

  Further, as shown in FIG. 3, on the transparent substrate 32, a light receiving monitor unit 52 in which a dummy mask pattern for light receiving monitoring is formed is formed in a region that does not overlap with any of the nozzle plate forming units 50 described above. The light receiving sensor 48 is disposed at a corresponding position directly below the light receiving monitor unit 52. In other words, the light receiving sensor 48 is arranged in an area (an area other than the nozzle plate forming part) that does not overlap with any nozzle plate forming part 50 on the stage 20.

  Note that the shape, the number of arrangement, and the arrangement position of the nozzle plate forming unit 50 and the light receiving monitor unit 52 on the transparent substrate 32 can be various, and are not limited to the example of FIG.

  FIG. 4 is a block diagram of the light source 12 and the irradiation optical system 14 used in the exposure apparatus 10 shown in FIG. As shown in FIG. 4, the illumination unit 60 used in the exposure apparatus 10 of this example uses an ultrahigh pressure mercury lamp 61 as a light source. The light emitted from the ultra-high pressure mercury lamp 61 is collected by the elliptical condenser mirror 62, the optical path is bent in the horizontal direction by the plane reflecting mirror 63, and then enters the integrator lens 64.

  The light whose illuminance distribution has been made uniform by the integrator lens 64 is selected by the light source filter 65 and then the light path is bent by the planar reflection mirror 66 in the vertical direction and enters the collimator lens 67. The light converted into parallel light by the collimator lens 67 is irradiated toward the irradiation surface 68 as parallel irradiation light having a uniform illuminance distribution.

  In this example, of the light source spectrum of the ultrahigh pressure mercury lamp 61 shown in FIG. 5, the i-line (wavelength = 365 nm) and the wavelength region in the vicinity thereof are used, and the optical filter 65 described in FIG. In the light source spectrum of the ultra-high pressure mercury lamp 61, a filter that transmits the i-line and the wavelength region in the vicinity thereof, that is, a filter that cuts the long-wavelength side such as the h-line (405 nm) is used. More preferably, a filter that cuts light on the short wavelength side such as j-line (313 nm) or 334 nm is further used.

  The type and wavelength of the light source to be used are not limited to the above example, and an appropriate light source (wavelength) is selected in relation to the photosensitive characteristics of the photoresist to be used. In carrying out the present invention, a mode in which a solid-state laser, a semiconductor laser (for example, wavelengths: 355 nm, 375 nm, 405 nm) or the like is used as a light source for illumination is also possible.

  FIG. 6 is a graph showing the spectral characteristics of transmittance in the optical interference film 34 used in the exposure mask 22 of this example. The horizontal axis indicates the wavelength, the vertical axis indicates the transmittance, and the characteristics when the incident angle of light is 0 degrees, 15 degrees, 30 degrees, and 45 degrees are shown. As shown in FIG. 6, the transmission wavelength band tends to shift to the short wavelength side as the incident angle of light increases (when the light is irradiated obliquely).

  As described above, in this embodiment, the i-line (wavelength = 365 nm) of the ultrahigh pressure mercury lamp 61 is mainly used as the light source for exposure (see FIGS. 4 and 5). Looking at the wavelength of 365 nm in FIG. 6, when the incident angle is 0 degree (perpendicular incidence), the transmittance is almost 0%, the transmittance gradually increases as the incident angle increases, and when the incident angle is 45 degrees, the transmittance is increased. Almost 90%. Utilizing such characteristics, exposure is performed while switching the incident angle.

  Next, the configuration of the means for changing the incident angle will be described.

  FIG. 7 is a block diagram of the stage tilt rotation mechanism and its surroundings in the exposure apparatus 10 of this example. The rotating shaft 28 of the stage 20 is attached in a state of penetrating the bottom surface of the immersion container 16, and a liquid (for example, pure water 70) in the immersion container 16 is attached to a connection portion that penetrates the immersion container 16. Waterproofing is applied so as not to leak from this portion, and a spherical bearing 72 is provided so that the rotation of the rotary shaft 28 and adjustment (oscillation) of the tilt angle are possible.

  That is, the rotary shaft 28 of the stage 20 is supported in a state of penetrating the liquid immersion container 16 via a spherical bearing 72 attached to the bottom surface of the liquid immersion container 16, and the lower end of the rotary shaft 28 has a free joint 74. And an output shaft 78 of a motor 76 (referred to as “stage rotation motor”). The stage rotation motor 76 is fixed to a slider 82 that slides along a linear motion guide 80, and the stage rotation motor 76 is linearly moved together with the slider 82 by driving a motor (referred to as an “inclined rocking motor”) 84. It can be moved along the guide 80.

  By moving the stage rotation motor 76 on the slider 82 in the left-right direction in FIG. 7 by driving the tilt swing motor 84, the rotation shaft 28 of the stage 20 can be swung around the fixed point 86 of the spherical bearing 72. The tilt angle of the rotary shaft 28 (that is, the tilt angle of the table surface) can be adjusted by the swing position. Thereby, the incident angle of the light with respect to the exposure mask 22 can be changed.

  Further, when the output shaft 78 is rotated by driving the stage rotation motor 76, the rotational force is transmitted to the rotation shaft 28 via the universal joint 74, and the stage 20 is rotated.

  A liquid pump 88 is provided in the liquid immersion container 16 in which the stage 20 is accommodated, and the liquid pump 88 can supply and discharge liquid for immersion (here, pure water 70).

  During immersion exposure, pure water 70 is introduced into the immersion vessel 16 via the liquid pump 88, and the immersion vessel 16 is filled with the pure water 70. In normal exposure (during dry exposure), pure water 70 is discharged from the immersion vessel 16 and the inside of the immersion vessel 16 is replaced with gas (for example, air).

  In addition to the pure water 70, the immersion liquid includes a dedicated immersion liquid prepared for use in an exposure apparatus. In some cases, such an exclusive liquid is used. It is also possible.

  When the immersion exposure is performed, the exposure light is absorbed by the liquid covering the periphery of the exposure mask 22. When light is incident perpendicular to the liquid surface and light is irradiated substantially perpendicularly to the exposure mask 22 (in the case of vertical exposure or narrow-angle incident exposure), the light traveling in the liquid reaches the exposure mask 22. Since the distance (optical path length) until completion is substantially constant at each position of the exposure mask 22, the absorption of exposure light by the liquid can be considered to be uniform (substantially uniform) at each position on the exposure mask 22. The only problem is that it is attenuated (including substantially uniform having a range distribution).

  However, in the case of performing oblique exposure with light incident on the liquid surface and a relatively large incident angle with respect to the exposure mask 22, the exposure light is incident on the liquid surface perpendicularly. The distance (optical path length) of the traveling light to reach the exposure mask 22 varies depending on the location at each position of the exposure mask 22. Due to the difference in the amount of light absorption due to the difference in optical path length, a light amount distribution is generated on the exposure mask 22, thereby making the exposure of the resist 24 uneven.

  Specifically, in a region where the distance (optical path length) until the exposure light is incident on the liquid and reaches the surface of the exposure mask 22 is short, the attenuation of the exposure light is small, so that the exposure light reaches the surface of the exposure mask 22. Although the amount of exposure light is relatively large, the photoresist coated on the back surface of the exposure mask 22 can be sufficiently exposed, but the distance (optical path) until the exposure light reaches the surface of the exposure mask 22 after entering the liquid. In the long region, the attenuation of the exposure light is large, so the amount of exposure light reaching the surface of the exposure mask 22 is less than that when the optical path length is short, and the photoresist cannot be sufficiently exposed with the same exposure time. . On the other hand, if exposure is performed with an exposure time sufficient to perform exposure in a region with a long optical path length, overexposure occurs in a region with a short optical path length, and the photoresist is not exposed in the same state as the region with a long optical path length. For this reason, the photosensitivity of the photoresist becomes non-uniform.

  For this reason, in the present embodiment, the transmission correction plate 18 for correcting the transmittance distribution is used so that a uniform light amount distribution can be obtained on the exposure mask 22 during the oblique exposure in the liquid. The transmission correction plate 18 is a transmittance gradient substrate having a transmittance distribution corresponding to the distance (optical path length) until the light incident on the liquid reaches the exposure mask 22, and after being incident on the liquid, the exposure mask. The transmittance is high in the region where the distance (optical path length) until reaching 22 is long, and the transmittance is low in the region where the distance (optical path length) until reaching the exposure mask 22 after entering the liquid is short. It is configured.

  The transmission correction plate 18 is attached to the upper part of the immersion container 16 via an opening / closing hinge 90, and the transmission correction plate 18 seals the top surface of the immersion container 16 by the opening / closing hinge 90 and the top surface. It is possible to move to a position outside the exposure area retracted from.

  In the present embodiment, during vertical exposure or tilt exposure with a relatively small incident angle (referred to as a “narrow angle tilt rotation exposure process”), the transmission correction plate 18 is moved out of the exposure area and incident. In the case of tilt exposure with a relatively large angle (referred to as “wide-angle tilt rotation exposure process”), the transmission correction plate 18 is moved to the upper part (position for sealing the top surface) on the immersion container 16 in the exposure area. Let

  Strictly speaking, an illuminance distribution is generated at the time of vertical exposure or a narrow-angle tilt rotation exposure process, but the narrow-angle taper has little influence and has no practical problem. Including the narrow-angle tilt exposure process, several types of appropriate transmission correction plates are prepared corresponding to the incident angle of light during tilted exposure, depending on the incident angle of light during tilted exposure. Thus, a mode in which the transmission correction plate is switched and used is also possible.

  By using the transmission correction plate 18 as described above, when the exposure light incident from the illumination unit 60 reaches the exposure mask 22 via the transmission correction plate 18 and the pure water 70 which is a liquid for immersion, the exposure mask. 22, the amount of exposure light is uniform over the entire surface. In this way, illuminance change according to the optical axis distance during tilt rotation and illuminance distribution in the plane can be corrected, so even when producing a relatively large size (long) nozzle plate, there is little variation and stable. Nozzle formation is possible.

  Further, by arranging the transmission correction plate 18 so as to be in contact with the surface of the pure water 70 which is an immersion liquid, that is, a boundary surface in contact with air, and performing exposure in a state where the liquid is filled, the liquid ripples and bubbles It is possible to prevent harmful effects peculiar to immersion exposure, such as entrainment of liquid.

  As another method for equalizing the amount of light on the exposure mask 22 during immersion tilt exposure, a method in which the exposure mask 22 and the liquid surface of the liquid used for immersion are parallel may be considered. Maintaining the exposure mask 22 in a parallel state at all times requires an apparatus for that purpose, leading to an increase in cost. Furthermore, when light is incident on the liquid surface at a large incident angle (when the incident light incident angle on the exposure mask 22 is large), the exposure light is totally reflected on the liquid surface, and the exposure light reaches the exposure mask. There is also the problem of not doing.

  Specifically, in the case of pure water having a refractive index of 1.44, if light is incident at an angle of about 45 degrees with respect to the liquid surface, the light is totally reflected, so that light is incident at a larger incident angle. It is not possible. Therefore, it is desirable that the exposure light is incident perpendicular to the liquid surface from the viewpoint of the configuration of the exposure apparatus. When a wide-angle taper is formed by tilt exposure using the immersion exposure apparatus, the transmission correction plate as described above is used. The embodiment to be used is preferable.

  In addition, a light receiving sensor 92 is provided in the liquid immersion container 16 so that the amount of light reflected by the exposure mask 22 can be measured. Thereby, it can be confirmed whether the attachment position of the exposure mask 22 and the inclination angle of the stage 20 are set at predetermined positions and angles. When the exposure mask 22 is floating with respect to the stage 20, since the direction of the reflected light is changed by the rotation of the stage 20, the amount of reflected light from the exposure mask 22 detected by the light receiving sensor 92 is Changes with rotation. Therefore, it is possible to detect whether or not the exposure mask 22 is securely fixed to the stage 20 by the fluctuation of the reflected light amount. Further, when the tilt angle of the stage 20 is not set at a predetermined tilt angle, the tilt angle of the stage 20 can be adjusted based on the amount of light reflected by the light receiving sensor 92 so that the predetermined tilt angle is obtained. It is.

  Furthermore, in this example, as described above, the tilt mechanism portion 94 is configured by the rotary shaft 28 of the stage 20, the universal joint 74, the stage rotary motor 76, the linear motion guide 80, the slider 82, the tilt swing motor 84, and the like. However, the entire optical axis including the tilt mechanism 94, the immersion container 16 and the stage 20 supported by the tilt mechanism 94 can be rotated in a horizontal plane around an axis parallel to the optical axis of the exposure light. A rotation motor 96 is provided. Since the optical axis rotation motor 96 is configured to rotate around the optical axis, the uniformity of the light quantity distribution can be further enhanced.

[Production process of exposure mask]
Next, a manufacturing method of the exposure mask 22 used in the exposure apparatus 10 having the above configuration will be described with reference to FIG.

As shown in FIG. 8A, first, the optical interference film 102 is formed on the entire surface of one side surface (upper surface in the drawing) of the transparent substrate 32 made of glass or the like. The optical interference film 102 is a so-called optical multilayer film in which high refractive index materials and low refractive index materials are alternately stacked. Al ₂ O ₃ (aluminum oxide) or TiO ₂ (titanium oxide) is used as the high refractive index material, and SiO ₂ (silicon oxide) or MgF ₂ (magnesium fluoride) as the low refractive index material. Is used.

  The optical interference film 102 is formed by alternately depositing these materials by a technique such as sputtering or vacuum deposition. In the present embodiment, a material and a film thickness are selected so as to realize the transmittance characteristic described with reference to FIG.

  Next, as shown in FIG. 8B, a resist 103 is applied over the entire surface of the optical interference film 102 on the transparent substrate 32 by a spin coater or the like and prebaked. Thereafter, exposure is performed using a mask (not shown) corresponding to the pattern of the opening region 40 of the target light blocking layer (corresponding to the opaque film 36 described in FIG. 2), and development is performed, whereby FIG. As shown in c), a resist layer 103b (mask layer) is formed only in a portion corresponding to the opening region 40 of the light blocking layer.

  Next, as shown in FIG. 8D, an opaque film 104 is formed on the entire surface of the transparent substrate 32 on which the resist layer 103b is formed. The opaque film 104 is made of Cr (chromium) or chromium oxide, and is formed by a method such as sputtering or vacuum deposition.

  As shown in FIG. 8D, after forming the opaque film 104 on the entire surface of the resist layer 103b, the entire transparent substrate 32 is immersed in an organic solvent, so-called lift-off, so-called lift-off. The opaque film 104 on the formed region is removed together with the resist layer 103b.

  As a result, as shown in FIG. 8E, the opaque film 104 remains only in the region where the resist layer 103b is not formed on the optical interference film 102, and the opaque layer 104b as the light blocking layer (in FIG. 2). (This corresponds to the opaque film 36 described above).

  After that, as shown in FIG. 8 (f), the portion that becomes the opening region 38 of the optical interference film 102 is removed by a laser trimmer or the like, whereby the optical interference film 102b that becomes the light selective layer (the light described in FIG. 2). Equivalent to the interference film 34). Thus, the exposure mask 22 used in the present embodiment is manufactured.

[Example 1 of nozzle plate manufacturing process]
Next, an example of a method for manufacturing a nozzle plate of an inkjet head using the exposure mask 22 configured as described above will be described.

  FIG. 9 is a flowchart showing the manufacturing process of the nozzle plate in the present embodiment.

  First, a negative type photoresist is applied on one side of the exposure mask 22 manufactured through the process described in FIG. 8 (step S102 in FIG. 9). Specifically, as shown in FIG. 10, a resist 24 is applied to the surface of the exposure mask 22 on the side where the optical interference film 34 (102b) and the opaque film 36 (104b) are formed by a spin coater or the like. . Since the film thickness of the resist 24 to be applied corresponds to the thickness of the nozzle plate to be manufactured, a thick film resist is used in this embodiment. For example, a negative resist is applied with a film thickness of about 20 to 50 μm (photosensitive material adhesion step).

  It should be noted that, instead of adhesion by coating, a method of closely contacting the exposure mask 22 using a dry film (DFR) or a method of closely contacting the resist mask 24 and the exposure mask 22 using a substrate coated with the resist 24 is used. May be.

  After step S102 in FIG. 9, pre-baking is performed on the exposure mask 22 coated with the resist 24 (step S104).

  Next, as described with reference to FIGS. 1 and 2, the pre-baked exposure mask 22 with a negative resist is fixed on the stage 20 of the exposure apparatus 10 with the transparent substrate 32 side up (exposure surface side). Exposure is performed from the transparent substrate 32 side (steps S106 and S108 in FIG. 9).

In the first exposure process shown in step S106, narrow-angle tilt rotation exposure is performed in which light is irradiated to the exposure mask 22 at a relatively small incident angle θ ₁ (eg, θ ₁ = 5 to 10 degrees). Specifically, as shown in FIG. 11A, dry exposure is performed in which light having an incident angle θ ₁ is irradiated from the transparent substrate 32 side of the exposure mask 22 in a gas atmosphere.

When light is irradiated from the transparent substrate 32 side of the exposure mask 22 at an incident angle θ ₁ , light does not pass through the portion other than the opening region 38 of the light interference film 34 due to the characteristics of the light interference film 34 described with reference to FIG. The transmittance is approximately 0%), and light passes only through the opening region 38. In the opaque film 36, an opening area 40 having a sufficiently larger diameter including the opening area 38 is formed. Therefore, the light that has passed through the opening area 38 of the optical interference film 34 is regulated by the opaque film 36. Without entering the layer of the resist 24 through the opening region 40. A part of the light transmitted through the resist 24 is reflected at the interface between the layer of the resist 24 and the gas layer 106 and returns into the resist 24. The resist 24 is exposed to an inverted frustoconical shape (inverted Taber shape) that is approximately twice the incident angle θ ₁ (for example, approximately 10 degrees when θ ₁ = 5 degrees) by the light including the interface reflected light.

  On the other hand, part of the light transmitted through the resist 24 passes through the interface with the gas layer 106 and enters the gas layer 106, but is absorbed by the antireflection film 46 on the stage surface facing the gas layer 106. Further reflections are prevented.

Subsequent to the narrow-angle tilt rotation exposure step (step S106 in FIG. 9), wide-angle tilt rotation exposure (second exposure process) shown in step S108 in FIG. 9 is performed. Specifically, as shown in FIG. 11B, immersion exposure is performed in which light with an incident angle θ ₂ (> θ ₁ ; for example, θ ₂ = 20 to 40 degrees) is irradiated in the liquid. As described with reference to FIG. 7, the immersion container 16 is filled with the liquid, and the exposure mask 22 is irradiated with light through the transmission correction plate 18.

As shown in FIG. 11B, when the light is irradiated from the transparent substrate 32 side of the exposure mask 22 at the incident angle θ ₂ , the light interference film 34 is other than the opening region 38 due to the characteristics of the light interference film 34 described with reference to FIG. Since this portion also transmits light, the opaque film 36 substantially functions as a light shielding mask. That is, light passes only through the opening region 40 of the opaque film 36, and the light passage range is regulated by the opening region 40. The resist 24 is exposed to light that has passed through the opening region 40 of the opaque film 36.

  The light that has passed through the resist 24 is prevented from being reflected at the interface with the liquid layer 108 formed on the back side of the resist layer (see FIG. 11B). The resist 24 is exposed to a frustoconical shape corresponding to the incident angle only by light incident from the opening region 40 of the opaque film 36, which hardly contributes to the exposure.

  After the narrow-angle tilt rotation exposure process (first exposure process: step S106 in FIG. 9) and the wide-angle tilt rotation exposure process (second exposure process: step S108 in FIG. 9), the resist has two different taper angles. A drum-shaped three-dimensional range in which two truncated cones are in contact with each other's upper surface (surface of a small area) and are combined vertically is exposed.

  Thereafter, in step S110 of FIG. 9, the resist 24 after exposure is developed and then post-baked. Thus, as shown in FIG. 12A, a resist pattern in which the resist 24 corresponding to the drum-shaped photosensitive portion remains is formed on the exposure mask 22, and this is used as a nickel (Ni) electroforming mold.

  That is, after step S110 in FIG. 9, first, nickel (Ni) eutectoid plating is performed on the exposure mask 22 after the development and post-baking (step S112) to form a liquid repellent plating layer. Specifically, as shown in FIG. 12B, the Ni eutectoid plating layer 113 is formed by performing nickel (Ni) eutectoid plating on the surface of the exposure mask 22 on which the opaque film 36 is formed.

  Ni eutectoid plating is performed using a plating solution containing PTFE (polytetrafluoroethylene) until a film thickness of 1 to 3 [μm] is obtained. Since Ni eutectoid plating is performed only on metal parts, in this example, the Ni eutectoid plating layer 113 is formed only on the surface of the opaque film 36 made of Cr.

  Then, Ni electroforming is performed in step S114 of FIG. Specifically, as shown in FIG. 12B, a Ni electroformed layer 114 is deposited on the Ni eutectoid plated region, that is, on the Ni eutectoid plated layer 113 by Ni electroforming. The film thickness of Ni deposited at this time is 10 to 50 [μm]. A metal plate portion formed by the Ni eutectoid plating layer 113 and the Ni electroformed layer 114 becomes the nozzle plate 115.

  After polishing the growth surface by plating, the resist 24 is removed with an organic solvent or the like (step S116 in FIG. 9), and then the nozzle plate formed by the Ni eutectoid plating layer 113 and the Ni electroforming layer 114. 115 is peeled off from the exposure mask 22 (step S118 in FIG. 9).

  Thus, as shown in FIG. 12C, the forward taper portion 116 whose flow passage cross-sectional area gradually decreases in the discharge direction (downward in the figure) and the wide-angle reverse taper portion 117 whose flow cross-sectional area gradually increases. As a result, a nozzle plate 115 formed with nozzles 118 having a “constricted shape” combined with the above is obtained. A wide-angle taper nozzle having such a “necked shape” is referred to as a “wide-angle taper nozzle with a neck” in this specification.

  According to the manufacturing method of this example, since the resist pattern exposed by exposure has a constricted portion, resist adhesion and electroforming stability (current shielding) are improved. Further, since the nozzle of the nozzle plate obtained by the manufacturing method of this example has a constricted portion, the influence of the nozzle surface is alleviated and the discharge stability is improved. Furthermore, since it is a metal material, it has high rigidity and can easily achieve the thinning required for high-viscosity and high-speed refilling.

  It is also possible to further improve the quality of the discharge surface by forming a sacrificial layer such as Cu or Zn before deposition of the Ni eutectoid plating layer 113 and removing it after peeling from the exposure mask 22.

[Example 2 of nozzle plate manufacturing process]
Next, a nozzle plate having a structure in which a counterbore shape is added around the nozzle on the discharge surface side of the narrow-angle tapered nozzle described in FIG. 12C and a hydrophilic trap groove is added in the vicinity of the nozzle on the discharge surface is manufactured. How to do will be described. The basic manufacturing procedure is the same as the example described with reference to FIGS. 9 to 12, and there are differences in the exposure mask to be used and the exposure process. Therefore, the differences will be mainly described.

  FIG. 13 is an explanatory diagram of an exposure process applied to manufacture of the target nozzle plate. In FIG. 13, elements that are the same as or similar to those shown in FIG. 11 are given the same reference numerals, and descriptions thereof are omitted.

  When a counterbore shape is added to the discharge surface side of the narrow-angle tapered nozzle with a constriction and a trap groove is added near the nozzle, an opaque film is used as shown in FIG. 13A instead of the exposure mask 22 described in FIG. An exposure mask 122 is used in which a part of 36 is composed of semi-transparent films 120 and 121 such as a lattice pattern.

  That is, the exposure mask 122 includes a semi-transparent film (corresponding to a “first semi-transmissive region”) 120 that contributes to the formation of a counterbore shape and a semi-transparent film that contributes to the formation of the trap groove in part of the opaque film 36 (Corresponding to “second translucent region”) 121. The counterbore forming semi-transparent film 120 is concentrically formed in contact with the opening region 40 around the outside of the opening region 40. On the other hand, the trap groove forming semi-transparent film 121 is provided in a strip shape at an appropriate position (position where the trap groove is to be formed) away from the counterbore forming semi-transparent film 120.

  The transmittance of each of the semi-transparent films 120 and 121 is appropriately designed according to the target counterbore depth and the trap groove depth. In this example, in order to make the depth of the trap groove deeper than the depth of the counterbore, the transmittance of the semitransparent film 121 for trap groove formation is set higher than the transmittance of the semitransparent film 120 for counterbore formation. . The desired transmittance is realized by the density of the lattice patterns constituting the translucent films 120 and 121, respectively.

  Using the above-described exposure mask 122, as shown in FIG. 13A, first, a narrow angle tilt rotation exposure process is performed in a gas. At this time, as described with reference to FIG. 11A, since the light interference film 34 blocks the light, the light passes only through the opening region 38, and the inverted frustoconical shape is formed by the light incident from the opening region 38 and the reflection on the resist back surface. Is exposed.

Next, as shown in FIG. 13B, a wide-angle tilt rotation exposure process is performed in the liquid. At this time, the light interference film 34 also transmits light through portions other than the opening region 38. The point that the resist 24 is exposed in a truncated cone shape by the light passing through the opening region 40 of the opaque film 36 is as described with reference to FIG. In the configuration of FIG. 13B, the periphery of the inverted frustoconical photosensitive portion is substantially cylindrical with a predetermined depth d ₁ by a small amount of light transmitted through the translucent film 120 formed around the opening region 40. Exposed to shape.

Since the substantially cylindrical photosensitive region 125 having the depth d ₁ is a portion corresponding to a counterbore, the transmittance and exposure of the translucent film 120 are set so that d ₁ becomes smaller than the height h ₁ of the constricted portion. The amount is adjusted.

Similarly, the portion (reference numeral 126) corresponding to the trap groove having the depth d ₂ (> d ₁ ) is exposed by the light transmitted through the translucent film 121 for forming the trap groove.

  After the exposure process described in FIGS. 13A and 13B, development and post-baking are performed, and using the obtained resist pattern, Ni eutectoid plating and Ni electroforming are performed to produce a nozzle plate. This is the same as the example described in FIG. 9 (see step S110 to step S118 in FIG. 9).

  That is, as shown in FIG. 14A, nickel (Ni) eutectoid plating is performed on the surface of the exposure mask 22 on which the opaque film 36 is formed to form a Ni eutectoid plating layer 113 as a liquid repellent layer. In addition, although the conductive film is not formed on the resist pattern upper surface of the photosensitive region portion 125 corresponding to the counterbore portion, the photosensitive region is exposed from the end surface of the counterbore portion as the deposition of the plating layer on the region of the opaque film 36 proceeds. A plating layer runs on the resist pattern upper surface of the portion 125, and the resist pattern upper surface of the photosensitive region portion 125 corresponding to the counterbore portion is also covered with the Ni eutectoid plating layer 113.

The film thickness d ₃ of the Ni eutectoid plating layer 113 is smaller than the resist pattern height (that is, the depth d ₂ of the trap groove 130) of the photosensitive region 126 corresponding to the trap groove, and in the counterbore portion. It is formed to the extent that the entire upper surface of the resist pattern of the corresponding photosensitive region 125 is covered.

Next, a Ni electroformed layer 114 is deposited on the Ni eutectoid plated layer 113 by Ni electroforming. Since the Ni electroformed layer formed by the Ni electroforming method isotropically grows, when the resist pattern height (d ₂ ) of the photosensitive region portion 126 corresponding to the trap groove is exceeded, the resist of the photosensitive region portion 126 is formed. It rides on the upper surface of the pattern and eventually grows so as to cover the upper surface of the photosensitive region portion 126.

As a result, as shown in FIG. 14A, when the Ni electroformed layer 114 is grown to a target predetermined height h ₂ , the resist pattern upper surface portion of the photosensitive region portion 126 corresponding to the trap groove is concave. A Ni electroformed layer 114 that is recessed is formed. The recess 140 functions as an adhesive escape groove.

  Then, after polishing the plating growth surface (the upper surface of FIG. 14A), the resist pattern is removed with an organic solvent or the like, and the nozzle formed by the Ni eutectoid plating layer 113 and the Ni electroforming layer 114. The plate 150 is peeled off from the exposure mask 22.

Thus, as shown in FIG. 14 (b), a narrow angle tapered nozzle 118 with a constriction having a counterbore 152 around the nozzle on the discharge surface, the trap groove 130, and an adhesive escape groove (recess 140) on the opposite side of the discharge surface. The formed nozzle plate 150 is completed. Since the discharge surface side of the nozzle plate 150 is formed of the Ni eutectoid plating layer including the inside of the counterbore portion 152, it has liquid repellency. Further, since at least the top surface portion of the trap groove 130 is formed by the Ni electroformed layer 114, it becomes lyophilic. Furthermore, the width W ₁ of the recess 140 that functions as an adhesive escape groove is formed narrower than the nozzle inflow side opening diameter D ₁ .

  As shown in FIG. 14C, the manufactured nozzle plate 150 is joined to a communication plate 156 (a flow channel forming member for forming a flow channel communicating with the nozzle) that constitutes the liquid ejection head, and The liquid discharge head is manufactured by stacking and joining other flow path forming members (not shown) on the communication plate 156.

  An adhesive (for example, an epoxy-based adhesive) is used for joining between the nozzle plate 150 and the communication plate 156, but the remainder of the adhesive (excess adhesive) on the joint surface is an adhesive escape groove formed by the recess 140. Therefore, the surplus adhesive does not protrude into the nozzle flow path and the like, and it is possible to perform clean bonding with a high yield. In addition, it is possible to relieve the stress caused by the difference in the coefficient of linear expansion of the nozzle plate 150, the communication plate 156, and the adhesive that joins them.

  According to the nozzle plate 150 of the present embodiment, since the aperture diameter of the nozzle portion is defined by the constricted portion, even if the dimensional accuracy of the counterbore portion 152 varies, relatively stable ejection is possible. In addition, the addition of the counterbore part 152 improves the reliability with respect to jamming and wiping.

  Furthermore, according to the manufacturing method of this example, even if mask back surface reflection occurs at the time of narrow-angle tilt rotation exposure described with reference to FIG. In addition, according to the manufacturing method of this example, the film thickness can be reduced as compared with the case where the mask of the base material is made thicker than the counterbore height, so that application of resist such as coating or dry film (DFR) lamination is also stable. There is an advantage that can be done.

  FIG. 15 is a plan view of the nozzle plate 150 viewed from the discharge surface side. As shown in the figure, the nozzle plate 150 is formed with a structure in which a plurality of constricted wide-angle taper nozzles 118 serving as droplet discharge ports are two-dimensionally arranged in a matrix, and concentric counterbores around each nozzle hole. 152 is formed.

  In the illustrated matrix arrangement, the horizontal direction in FIG. 15 is the row direction (main scanning direction in a full-line inkjet recording apparatus described later), and the vertical direction in FIG. 15 (sub-scanning direction in a full-line inkjet recording apparatus described later) is a column. Direction, the narrow-angle tapered nozzle 118 with a constriction is arranged in a straight line along a row direction and an oblique column direction having a constant angle α not orthogonal to the row direction, and is arranged in a two-dimensional array in an oblique lattice shape as a whole. Has been.

  In addition, a strip-shaped trap groove 130 having a constant width is formed along the row direction between the rows of nozzle columns along the row direction (between rows arranged in the sub-scanning direction).

In FIG. 15, it is assumed that the nozzle interval NLm in the nozzle column of each row along the row direction is constant (the nozzle intervals in the main scanning direction of each row are all the same NLm), and the column interval of the nozzle columns of each row along the row direction. When (the row interval in the sub-scanning direction) is Ls (constant), the substantial nozzle interval (main scanning direction projection nozzle pitch) P _N projected so as to be aligned in the row direction is Ls / tan α. Become. The number of rows nozzle rows along the row direction when the (column number of nozzles) is n, satisfies the relationship NLm = n × P _N (where, n is a natural number). Although the case where n = 6 is illustrated in FIG. 15, in the practice of the present invention, the arrangement form of the nozzles is not particularly limited, and various arrangement forms are possible.

  According to the nozzle plate 150 of this example, the trapping property (liquid trapping property) at the time of wiping is improved by the hydrophilic trap groove 130.

[Second Embodiment]
In the embodiment described above, an example of controlling the use and suppression of resist back surface reflection by switching between dry exposure and immersion exposure and using the difference in refractive index between the gas layer 106 and the liquid layer 108 on the resist back surface has been described. However, in place of the above-described aspect, an aspect in which a reflective member is provided on the back side of the resist is also possible. The embodiment will be described below.

  FIG. 16 is an explanatory diagram showing an example of an exposure process for controlling the back surface reflection of a resist using a reflecting member. In FIG. 16, elements that are the same as or similar to those shown in FIG. 11 are given the same reference numerals, and descriptions thereof are omitted.

  In the configuration shown in FIG. 16, the reflecting member 170 is provided on the surface of the stage 20 facing the back surface of the resist 24, and the position where the reflecting member 170 approaches the back surface of the resist 24 (FIG. 16A), It is configured to be movable to a distant position (FIG. 16B).

  As shown in FIG. 16A, when the reflecting member 170 is brought close to the back surface of the resist 24 (preferably in a close contact state), the light transmitted through the resist 24 is reflected on the surface of the reflecting member 170. Then, since it returns to the resist 24, the same exposure action as in FIG. 11A is obtained.

  Further, the reflecting member 170 is equivalent to or slightly larger than the irradiation range when the light incident through the opening region 38 of the exposure mask 22 reaches the lower surface of the resist layer in the case of FIG. It has a reflective area. As shown in FIG. 16B, in the case of wide-angle tilt exposure, light is incident obliquely from the aperture region 40. Therefore, if the reflecting member 170 having a relatively small reflecting area as shown is moved away from the resist back surface, as shown in FIG. , The reflection member 170 does not receive light. As a result, in the case of FIG. 16B, the reflected light from the reflecting member 170 cannot be obtained, and the same exposure action as in FIG. 11B is obtained.

  Note that both of the exposure processes in FIGS. 16A and 16B are performed in a state where an immersion liquid (for example, pure water) is filled. Since the resist back surface reflection is reduced by exposure in the liquid, higher accuracy can be achieved.

  FIG. 17 is a view showing an example in which the same exposure process as that in FIG. 16 is performed using the exposure mask 122 described in FIG. In FIG. 17, the same or similar elements as those shown in FIGS. 13 and 16 are denoted by the same reference numerals, and the description thereof is omitted.

  As illustrated in FIG. 16, exposure using reflected light can be performed by bringing the reflecting member 170 in FIG. 17 closer to the back surface of the resist 24, and reflected light can be performed by moving the reflecting member 170 away from the back surface of the resist 24. Therefore, the exposure process similar to the exposure process described in FIG. 13 can be obtained by the exposure process shown in FIGS. A nozzle plate with counterbore and trap grooves is obtained.

[Third Embodiment]
In the first and second embodiments described above, the method using a negative resist has been described. However, it is also possible to produce a nozzle plate using a positive resist. Hereinafter, an example using a positive resist will be described as the third embodiment.

  FIG. 18 is a flowchart illustrating a procedure of a nozzle plate manufacturing method according to the third embodiment. In the manufacturing procedure shown in FIG. 18, steps S302 to S308 are similar to the manufacturing procedure described in FIG.

  That is, as shown in FIG. 18, first, a positive type resist (positive resist) is applied on the exposure mask (step S302). Specifically, as in the example described with reference to FIGS. 10 and 13, a positive type resist is applied to the surfaces of the exposure masks 22 and 122 where the light interference film and the light blocking film are formed by spin coater or squeegee application. To do. The film thickness of the resist is, for example, about 20 to 50 μm.

  In addition, it replaces with adhesion by application | coating, the method of sticking to an exposure mask using a dry film (DFR), or the method of sticking the exposure mask and the surface which apply | coated the positive resist using the board | substrate with which the positive resist was apply | coated. It may be.

  After step S302 in FIG. 18, pre-baking is performed on a positive resist applied to the exposure mask (step S304).

  Next, as described with reference to FIGS. 1 and 2, the pre-baked exposure mask with a positive resist is fixed on the stage 20 of the exposure apparatus 10 with the transparent substrate 32 side up (exposure surface side), and is transparent. Exposure is performed from the substrate 32 side (steps S306 and S308 in FIG. 18).

  These steps (steps S306 and S308) are similar to steps S106 and S108 described with reference to FIG.

  After step S308 in FIG. 18, in step S310, exposure (backside exposure) is performed using another exposure mask for forming an adhesive escape groove from the backside of the exposure mask (the side where the positive resist is attached).

  In FIG. 19A, an adhesive is used for resist exposure of the constricted wide-angle taper nozzle and the portion corresponding to the counterbore part and the trap groove using the exposure mask similar to the exposure mask 122 described in FIG. A state of performing back surface exposure for forming a relief groove is shown.

  In FIG. 19, the same or similar elements as those shown in FIGS. 13 and 14 are denoted by the same reference numerals, and the description thereof is omitted.

  That is, as shown in FIG. 19A, the surface on which the positive resist 180 on the back surface of the exposure mask 122 is applied is exposed using another exposure mask (corresponding to “groove forming exposure mask”) 184. Do. On the exposure mask 184, a pattern of a semi-transparent region (corresponding to a “third semi-transmissive region”) 186 corresponding to a desired adhesive escape groove is formed. The back exposure process using the exposure mask 184 is performed by irradiating the exposure mask 184 with light perpendicularly. By this backside exposure process, the positive resist 180 in the region 180A that will later become the adhesive escape groove 188 is exposed.

To ensure that the width of the adhesive escape groove 188 is narrower than the nozzle inlet side opening diameter D _2, the width W ₂ of the semi-transparent region 186 nozzle inlet side opening diameter D ₂ Wayori also to narrow.

  After the back surface exposure process described above, in step S312 of FIG. 18, the positive resist 180 on the exposure mask 122 is developed and then post-baked. As a result, a resist pattern is formed in which the portions exposed in the exposure process (steps S306 to S310) are removed. The remaining resist pattern constitutes the nozzle plate 190.

  Next, in step S314 of FIG. 18, a protective film is applied to the post-baked resist pattern. This is formed in order to improve the liquid resistance against ink since the main material constituting the nozzle plate is a positive resist (resin). At least the inner surface of the nozzle is preferably coated with a protective film.

  Thereafter, as shown in FIG. 19B, the communication plate 156 is joined to the layer of the positive resist 180 (step S316 in FIG. 18). Note that, as described in the example of FIG. 14, the bonding reliability is improved by the excessive adhesive entering the adhesive escape groove 188 during the bonding.

  Thus, after bonding the positive resist 180 and the communication plate 156 (FIG. 19B), the exposure mask 122 is peeled off (step S318 in FIG. 18), and the laminated body (communication with the nozzle plate 190) shown in FIG. A structure in which the plate 156 is laminated and bonded is obtained.

  Thereafter, a liquid repellent coating is performed on the discharge surface 190A of the nozzle plate 190 (step S320 in FIG. 18), and a liquid repellent layer is formed on the discharge surface. Thereafter, another flow path forming substrate (not shown in FIG. 19) constituting the liquid ejection head is overlapped and joined to the communication plate 156 (step S322 in FIG. 18). The target liquid discharge head is manufactured through the above steps.

  Also in the method using the positive resist described above, the exposure process using the reflecting member 170 described with reference to FIGS. 16 to 17 can be applied.

[Control of corrected exposure]
Here, the details of the correction exposure applied to the first to third embodiments described above will be described.

  FIG. 20 is a configuration diagram of a light receiving monitor unit that monitors light transmitted through an exposure mask with a resist. As described with reference to FIG. 3, a dummy mask pattern similar to that of the nozzle plate forming unit 50 is formed in the light receiving monitor unit 52, and the light receiving sensor 48 is disposed directly below the dummy mask pattern.

  As shown in FIG. 20, on the light-receiving surface side of the light-receiving sensor 48, an opaque film 194 as a means for shielding light transmitted through the opening region 38D of the light interference film 34 in the dummy pattern during the wide-angle tilt rotation exposure process. Is provided. As described with reference to FIG. 11 and the like, in the wide-angle tilt rotation exposure process, reverse-tapered photosensitivity is performed mainly by light transmitted through the opening region 40 of the light blocking layer. Therefore, from the viewpoint of more accurately monitoring the amount of light transmitted through the opening area 40 (corresponding to the opening area 40D in the dummy pattern of FIG. 20), as shown in FIG. An impermeable film 194 is provided to prevent light received directly from the opening region 38D. With such a configuration, it is possible to perform accurate exposure correction during reverse tapered resist exposure.

  FIG. 21 is a flowchart of a process including correction exposure.

  First, an exposure mask with a resist is set on the stage of the exposure apparatus (step S402). Next, narrow angle tilt rotation exposure is performed, and exposure is performed to expose the forward tapered shape frustoconical range to the resist.

  At this time, the amount of light transmitted through the resist is monitored by the light receiving sensor 48 described with reference to FIG. 20, and exposure control is performed while correcting the illuminance from the illumination unit 60, the irradiation time, or a combination thereof so as to obtain an appropriate exposure amount. Do.

  Next, as described with reference to FIGS. 11 and 13, the immersion liquid is filled or the reflecting member 170 described with reference to FIGS. 16 and 17 is retracted (step S404 in FIG. 21). Wide angle tilt rotation exposure is performed with the reflection suppressed (step S406). As described with reference to FIG. 11 and the like, the resist can be exposed to an inverted tapered frustoconical (inverted frustoconical) range by the wide-angle tilt rotation exposure process. At this time, the amount of light transmitted through the resist is monitored by the light receiving sensor 48 described with reference to FIG. 20, and the illuminance from the illumination unit 60, the irradiation time (exposure time), or a combination thereof is corrected so as to obtain an appropriate exposure amount. Exposure control is performed.

  If a positive resist is used, the process further proceeds to step S410 in FIG. 21, and back exposure is performed as necessary, such as forming a groove corresponding to the adhesive relief groove. The exposure amount at this time is appropriately corrected from the measurement result in step S404 or S408.

  After completion of the exposure process, as described with reference to FIGS. 9 and 18, etc., processing such as development and post-baking is performed, and the substrate of the exposure mask is removed (step S412 in FIG. 21).

[Example of arrangement of mask pattern corresponding to nozzle plate forming part on transparent substrate]
In FIG. 3, the example in which the four nozzle plate forming portions are arranged side by side on the transparent substrate 32 has been described. However, in consideration of the characteristics of the rotary stage, the mask pattern corresponding to the nozzle plate forming portion is symmetrical on the transparent substrate. The aspect arrange | positioned in is preferable.

  An example is shown in FIG. In FIG. 22A, the nozzle plate forming portions Ai, Bi, Ci, Di, and Ei (i = 1 to 4) are arranged so as to have a rotationally symmetrical positional relationship of 90 degrees around the rotation center of the substrate. Has been. That is, in FIG. 22A, the four nozzle plate forming portions indicated by Ai (i = 1 to 4) are in rotationally symmetric positions with respect to the rotation center. Similarly, with respect to Bi, Ci, Di, and Ei (i = 1 to 4), the four nozzle plate forming portions having different i numbers are at 90-degree rotational symmetry positions. That is, a group of nozzle plate forming portions having the same subscript i number A to E is arranged in a quarter circle partition area, and one nozzle block includes five nozzle plate forming portions in the quarter circle. As a result, a total of 4 blocks are formed at 90-degree rotationally symmetric positions.

  In the tilt rotation exposure of this example, the portions having a rotationally symmetric positional relationship with respect to the rotation center of the substrate have the same exposure conditions. Therefore, a mask pattern having a rotationally symmetric positional relationship as shown in FIG. The variation in quality between the nozzle plates formed in is extremely small. Therefore, the quality of the nozzle plate can be managed by classifying into five groups for each symmetrical position obtained from Ai, Bi, Ci, Di, and Ei.

  If the nozzle plates at symmetrical positions are used in the same apparatus, the characteristics can be easily aligned, and correction values can be shared.

  For example, when applied to a print head of an inkjet recording apparatus that performs CMYK four-color recording, A1 to A4 are assigned to C heads, B1 to B4 are assigned to M heads, and C1 to C3 are assigned to Y heads, thereby realizing color recording. . By so doing, it is possible to reduce variations in the ejection heads within the apparatus (variations due to nozzle plate manufacturing accuracy).

  Alternatively, it is preferable to use A1 to A4 for connecting the short head module to realize the long length. By lengthening one ejection head using a nozzle plate at a symmetrical position, it is possible to reduce variations in ejection characteristics within the head.

  In the arrangement example as shown in FIG. 22B, each nozzle plate forming portion Ai, Bi, Ci, Di, Ei (so as to have a rotationally symmetrical positional relationship of 180 degrees around the rotation center of the substrate. i = 1 to 4) are arranged. That is, in FIG. 22B, the two nozzle plate forming portions indicated by A1 and A3 are in a rotationally symmetric position of 180 degrees with respect to the rotation center, and the two nozzle plate forming portions are rotated by A2 and A4. It is in a rotationally symmetrical position of 180 degrees with respect to the center. Similarly, for Bi, Ci, Di, and Ei (i = 1 to 4), the two nozzle plate forming portions with i = 1 and 3 are in 180-degree rotationally symmetric positions, and i = 2, 4 with 2 The two nozzle plate forming portions are in a 180-degree rotationally symmetric position.

  Although A1 and A2 in FIG.22 (b) are the substantially same positional relationship, they are not in a rotationally symmetric relationship. Therefore, the arrangement mode of FIG. 22B is inferior to the arrangement mode of FIG. 22A, and the management type increases when the nozzle plate is managed for each rotationally symmetric position. That is, since the symmetry of the arrangement mode of FIG. 22 (a) is increased, the mode of FIG. 22 (a) is more preferable than FIG. 22 (b) from the viewpoint of reducing the management type.

[Overall configuration of inkjet recording apparatus]
Next, an example of an ink jet recording apparatus provided with an ink jet head using a nozzle plate manufactured by the nozzle plate manufacturing method according to the embodiment of the present invention will be described.

  FIG. 23 is an overall configuration diagram showing an outline of an ink jet recording apparatus which is an image forming apparatus according to an embodiment of the present invention. As shown in FIG. 23, the inkjet recording apparatus 210 includes a plurality of liquid ejection heads (hereinafter, simply referred to as “heads”) 212K, 212C, 212M, and 212Y provided for each ink color. 212, an ink storage / loading unit 214 that stores ink to be supplied to each of the heads 212K, 12C, 12M, and 12Y, a paper feeding unit 218 that supplies recording paper 216, and a decurl that removes curl from the recording paper 216 An adsorption belt that is disposed to face the processing unit 220 and the nozzle surfaces (ink ejection surfaces) of the heads 212K, 212C, 212M, and 212Y and conveys the recording paper 216 while maintaining the flatness of the recording paper 216 (recording medium). Remove the transport unit 222, the print detection unit 224 that reads the print results from the print unit 212, and the printed recording paper (printed material). And a paper output unit 226 for discharging the.

  The ink storage / loading unit 214 includes ink tanks that store inks of colors corresponding to the heads 212K, 212C, 212M, and 212Y, and the tanks 212K, 212C, 212M, and 212Y are connected to each other through a required pipe line. Communicated with. In addition, the ink storage / loading unit 214 includes notifying means (display means, warning sound generating means) for notifying when the ink remaining amount is low, and has a mechanism for preventing erroneous loading between colors. ing.

  In FIG. 23, a magazine for rolled paper (continuous paper) is shown as an example of the paper supply unit 218, but a plurality of magazines having different paper widths, paper quality, and the like may be provided. Further, instead of the roll paper magazine or in combination therewith, the paper may be supplied by a cassette in which cut papers are stacked and loaded.

  When multiple types of recording paper are used, an information recording body such as a barcode or wireless tag that records paper type information is attached to the magazine, and the information on the information recording body is read by a predetermined reader. Therefore, it is preferable to automatically determine the type of paper to be used and perform ink ejection control so as to realize appropriate ink ejection according to the type of paper.

  The recording paper 216 delivered from the paper supply unit 218 retains curl due to having been loaded in the magazine. In order to remove the curl, heat is applied to the recording paper 216 by the heating drum 230 in the direction opposite to the curl direction of the magazine in the decurling unit 220. At this time, it is more preferable to control the heating temperature so that the printed surface is slightly curled outward.

  After the decurling process, the recording paper 216 cut to a predetermined size by the cutter 228 is sent to the suction belt conveyance unit 222. The suction belt conveyance unit 222 has a structure in which an endless belt 233 is wound between rollers 231 and 232 and faces at least the nozzle surfaces of the heads 212K, 212C, 212M, and 212Y and the sensor surface of the print detection unit 224. The part to be made is a flat surface.

  The belt 233 has a width that is greater than the width of the recording paper 216, and a plurality of suction holes (not shown) are formed on the belt surface. As shown in FIG. 23, a suction chamber 234 is provided at a position facing the nozzle surface of the printing unit 212 and the sensor surface of the printing detection unit 224 inside the belt 233 that is stretched between the rollers 231 and 232. Then, the suction chamber 234 is sucked by the fan 235 to be a negative pressure, whereby the recording paper 216 on the belt 233 is sucked and held.

  The power of a motor (not shown) is transmitted to at least one of the rollers 231 and 232 around which the belt 233 is wound, so that the belt 233 is driven clockwise in FIG. 22 and held on the belt 233. The recording paper 216 is conveyed from left to right in FIG. In addition, instead of the suction suction method, an aspect using an electrostatic suction type transport mechanism is also possible.

  Since ink adheres to the belt 233 when a borderless print or the like is printed, the belt cleaning unit 236 is provided at a predetermined position outside the belt 233 (an appropriate position other than the print area). Although details of the configuration of the belt cleaning unit 236 are not illustrated, for example, there are a method of niping a brush roll, a water absorption roll, etc., an air blow method of blowing clean air, or a combination thereof. In the case where the cleaning roll is nipped, the cleaning effect is great if the belt linear velocity and the roller linear velocity are changed.

  A heating fan 240 is provided on the upstream side of the printing unit 212 on the paper conveyance path formed by the suction belt conveyance unit 222. The heating fan 240 heats the recording paper 216 by blowing heated air onto the recording paper 216 before printing. Heating the recording paper 216 immediately before printing makes it easier for the ink to dry after landing.

  Each of the heads 212K, 212C, 212M, and 212Y of the printing unit 212 has a length corresponding to the maximum paper width of the recording paper 216 targeted by the ink jet recording apparatus 210, and the nozzle surface has a recording medium of the maximum size. This is a full-line type head in which a plurality of nozzles for ejecting ink are arranged over a length exceeding at least one side (full width of the drawable range) (see FIG. 24).

  The heads 212K, 212C, 212M, and 212Y are arranged in the order of black (K), cyan (C), magenta (M), and yellow (Y) from the upstream side along the feeding direction of the recording paper 216. 212K, 212C, 212M, and 212Y are fixedly installed so as to extend along a direction substantially orthogonal to the conveyance direction of the recording paper 216.

  A color image can be formed on the recording paper 216 by ejecting different color inks from the heads 212K, 212C, 212M, 212Y while conveying the recording paper 216 by the suction belt conveyance unit 222.

  As described above, according to the configuration in which the full-line heads 212K, 212C, 212M, and 212Y having nozzle rows that cover the entire width of the paper are provided for each color, the recording paper 216 and the printing unit in the paper feeding direction (sub-scanning direction). The image can be recorded on the entire surface of the recording paper 216 by performing the operation of moving the 212 relatively once (that is, by one sub-scan). Thereby, high-speed printing is possible and productivity can be improved as compared with a serial scan type (shuttle type) head in which the recording head reciprocates in a direction perpendicular to the paper conveyance direction.

  In this example, the configuration of KCMY standard colors (four colors) is illustrated, but the combination of ink colors and the number of colors is not limited to this embodiment, and light ink, dark ink, and special color ink are used as necessary. May be added. For example, it is possible to add an ink jet head that discharges light ink such as light cyan and light magenta. Also, the arrangement order of the color heads is not particularly limited.

  The print detection unit 224 illustrated in FIG. 23 includes an image sensor (line sensor or area sensor) for imaging the droplet ejection result of the printing unit 212, and nozzle clogging is performed from the droplet ejection image read by the image sensor. It functions as a means for checking ejection failures such as landing position deviation. Test patterns or practical images printed by the heads 212K, 212C, 212M, and 212Y of the respective colors are read by the print detection unit 224, and ejection determination of each head is performed. The ejection determination includes the presence / absence of ejection, measurement of dot size, measurement of dot landing position, and the like.

  A post-drying unit 242 is provided following the print detection unit 224. The post-drying unit 242 is means for drying the printed image surface, and for example, a heating fan is used.

  A heating / pressurizing unit 244 is provided following the post-drying unit 242. The heating / pressurizing unit 244 is a means for controlling the glossiness of the image surface, and pressurizes with a pressure roller 245 having a predetermined uneven surface shape while heating the image surface, and transfers the uneven shape to the image surface. To do.

  The printed matter generated in this manner is outputted from the paper output unit 226. It is preferable that the original image to be printed (printed target image) and the test print are discharged separately. The ink jet recording apparatus 210 is provided with a sorting means (not shown) for switching the paper discharge path in order to select the printed matter of the main image and the printed matter of the test print and send them to the respective discharge portions 226A and 226B. Yes. When the main image and the test print are simultaneously formed in parallel on a large sheet, the test print portion is separated by the cutter (second cutter) 248. Although not shown in FIG. 23, the paper output unit 226A for the target prints is provided with a sorter for collecting prints according to print orders.

[Head structure]
Next, the structure of the head will be described. Since the structures of the respective heads 212K, 212C, 212M, and 212Y for each color are common, the heads will be represented by the reference numeral 250 in the following.

  FIG. 25A is a plan perspective view showing a structural example of the head 250. As shown in FIG. 25A, the head 250 of this example has an ink chamber unit (recording corresponding to one nozzle) composed of a nozzle 251 which is an ink droplet ejection port, a pressure chamber 252 corresponding to each nozzle 251 and the like. It has a structure in which droplet discharge elements 253 as element units are arranged in a zigzag matrix (two-dimensionally), so that they are arranged along the longitudinal direction of the head (direction perpendicular to the paper feed direction). High density of the substantial nozzle interval (projection nozzle pitch) projected onto the screen is achieved. The nozzle 251 is a “wide-angle taper nozzle with a constriction” described with reference numeral 118 in FIG. 12, FIG. 14, FIG.

  In addition, a nozzle row having a length corresponding to the entire width of the recording medium 216 is formed in a direction (arrow M direction; main scanning direction) substantially orthogonal to the feeding direction of the recording medium 216 (arrow S direction; sub-scanning direction). The form is not limited to this example. For example, instead of the configuration of FIG. 25A, as shown in FIG. 25B, short head units 250 ′ in which a plurality of nozzles 251 are two-dimensionally arranged are arranged in a staggered manner and connected. The line head having a nozzle row having a length corresponding to the entire width of the recording medium 216 may be configured.

  The pressure chambers 252 provided corresponding to the respective nozzles 251 have a substantially square planar shape, and have outlets to the nozzles 251 and supply ink inlets (supply ports) at both corners on the diagonal line. 254 is provided. Note that the shape of the pressure chamber 252 is not limited to this example, and the planar shape may have various forms such as a quadrangle (rhombus, rectangle, etc.), a pentagon, a hexagon, other polygons, a circle, and an ellipse. Further, the arrangement of the nozzle 251 and the supply port 254 is not limited to the arrangement shown in FIGS. 25A and 25B. For example, the nozzle 251 may be arranged in the substantially central portion of the pressure chamber 252 or the pressure chamber. A supply port 254 may be disposed on the side wall side of 252.

  FIG. 26 is a cross-sectional view showing a three-dimensional configuration of a droplet ejection element for one channel (an ink chamber unit 253 corresponding to one nozzle 251). In the drawing, an example of the head 250 including the nozzle plate 150 described with reference to FIGS. 14 and 15 is shown. However, the nozzle plate 115 described with reference to FIG. 12 and the nozzle plate 190 described with reference to FIG. It is.

  As shown in FIG. 26, the head 250 has a structure in which a nozzle plate 150, a communication plate 156, a common flow path forming plate 260, a diaphragm plate 262, a pressure chamber forming plate 264, a vibration plate 266, and a piezoelectric element 268 are laminated and joined. .

  The communication plate 156 forms a part of a communication path (nozzle flow path) 270 that leads from the pressure chamber 252 to the nozzle 251 and also forms the floor surface of the common flow path 272 for supplying ink to each pressure chamber 252. It is a member to do. The common flow path forming plate 260 is a flow path forming member that forms a portion that becomes the side wall portion of the common flow path 272 and also forms a part of the communication path 270.

  The diaphragm plate 262 forms an ink supply port 254 as a throttle part (a narrowest part) of an individual supply path that guides ink from the common channel 272 to the pressure chamber 252 and a channel that forms a part of the communication path 270. It is a forming member. The pressure chamber forming plate 264 is a flow path forming member that forms a portion that becomes a side wall portion of the pressure chamber 252.

  The diaphragm 266 is a member constituting a part of the pressure chamber 252 (the top surface in FIG. 26) and is made of a conductive material such as stainless steel (SUS), and corresponds to each pressure chamber 252. It also serves as a common electrode for a plurality of piezoelectric elements 268 to be arranged. It is also possible to form the diaphragm with a non-conductive material such as resin. In this case, a common electrode layer made of a conductive material such as metal is formed on the surface of the diaphragm member.

  A piezoelectric body 274 is provided on the surface of the diaphragm 266 opposite to the pressure chamber 252 side (upper side in FIG. 26) at a position corresponding to each pressure chamber 252, and the upper surface (common electrode) of the piezoelectric body 274 is provided. The individual electrode 275 is formed on the surface opposite to the surface in contact with the diaphragm 266 that also serves as the same. A piezoelectric element (corresponding to an “actuator”) 268 is constituted by the individual electrode 275, a common electrode (here also serving as the diaphragm 266) facing the individual electrode 275, and a piezoelectric body 274 interposed so as to be sandwiched between these electrodes. Is done. A piezoelectric material such as lead zirconate titanate or barium titanate is preferably used for the piezoelectric body 274.

  26, the common flow path 272 communicates with an ink tank (not shown in FIG. 26, equivalent to the ink storage / loading unit 214 in FIG. 23) as an ink supply source, and is supplied from the ink tank. Ink is supplied to each pressure chamber 252 via the common flow path 272 of FIG.

  In a state where ink is filled in the pressure chamber 252, the piezoelectric element 268 is deformed by applying a driving voltage between the individual electrode 275 and the common electrode (also used as the vibration plate 266), and the volume of the pressure chamber 252 is changed, Ink is ejected from the nozzle 251 due to the pressure change accompanying this. After the ink is ejected, when the displacement of the piezoelectric element 268 is restored, new pressure ink is refilled into the pressure chamber 252 from the common flow path 272 through the ink supply port 254.

(Discharge recovery device)
FIG. 27 is a schematic diagram illustrating the configuration of an ink supply system and a discharge recovery device (maintenance unit) in the inkjet recording apparatus 210. The ink tank 290 is a base tank for supplying ink to the head 250, and is installed in the ink storage / loading unit 214 described with reference to FIG. In the form of the ink tank 290, there are a method of replenishing ink from a replenishing port (not shown) and a cartridge method of replacing the entire tank when the remaining amount of ink is low. When the ink type is changed according to the usage, the cartridge method is suitable. In this case, it is preferable that the ink type information is identified by a barcode or the like, and ejection control is performed according to the ink type.

  As shown in FIG. 27, a filter 292 is provided in the middle of the conduit connecting the ink tank 290 and the head 250 in order to remove foreign substances and bubbles. The filter mesh size is preferably equal to or smaller than the nozzle diameter of the head 250 (generally about 20 μm).

  Although not shown in FIG. 27, a configuration in which a sub tank is provided in the vicinity of the head 250 or integrally with the head 250 is also preferable. The sub-tank has a function of improving a damper effect and refill that prevents fluctuations in the internal pressure of the head.

  Further, the inkjet recording apparatus 210 is provided with a cap 294 as a means for preventing the nozzle from drying or preventing an increase in ink viscosity near the nozzle, and a cleaning blade 296 as a means for cleaning the nozzle surface 250A.

  The maintenance unit including the cap 294 and the cleaning blade 296 can be moved relative to the head 250 by a moving mechanism (not shown), and is moved from a predetermined retracted position to a maintenance position below the head 250 as necessary. It is like that.

  The cap 294 is displaced up and down relatively with respect to the head 250 by an elevator mechanism (not shown). The lifting mechanism is configured to cover the nozzle region of the nozzle surface 250A with the cap 294 by raising the cap 294 to a predetermined raised position when the power is turned off or waiting for printing, and bringing the cap 294 into close contact with the head 250. In addition, the cap 294 functions as a suction unit for suctioning the nozzle and can also function as a preliminary discharge ink receiver.

  The cleaning blade 296 is made of an elastic member such as rubber, and can slide on the ink ejection surface (nozzle surface 250A) of the head 250 by a blade moving mechanism (not shown). When ink droplets or foreign matter adheres to the nozzle surface 250A, the nozzle surface 250A is wiped by sliding the cleaning blade 296 on the nozzle surface 250A to clean the nozzle surface 250A.

  During printing or standby, when a specific nozzle 251 is used less frequently and the ink viscosity in the vicinity of the nozzle 251 increases, preliminary ejection is performed toward the cap 294 in order to discharge the deteriorated ink due to the increased viscosity. Is done.

  That is, if the head 250 is not ejected for a certain period of time, the ink solvent near the nozzles evaporates and the viscosity of the ink near the nozzles increases, and the ejection driving actuator (piezoelectric element 268) operates. However, the ink is no longer discharged from the nozzle 251. Therefore, before this state is reached (within the viscosity range in which ink can be ejected by the operation of the piezoelectric element 268), the piezoelectric element 268 is operated toward the ink receiver, and the ink in the vicinity of the nozzle whose viscosity has increased is removed. “Preliminary discharge” is performed. Further, after the dirt on the nozzle surface 250A is cleaned by a wiper such as a cleaning blade 296 provided as a cleaning means for the nozzle surface 250A, foreign matter is prevented from being mixed into the nozzle 251 by this wiper rubbing operation. Also, preliminary discharge is performed. Note that the preliminary discharge may be referred to as “empty discharge”, “purge”, “spitting”, or the like.

  When air bubbles are mixed in the ink in the head 250 (ink in the pressure chamber 252), the cap 294 is applied to the head 250, and the ink in the pressure chamber 252 (ink mixed with air bubbles) is sucked by the suction pump 297. The ink removed and sucked and removed is sent to the collection tank 298. This suction operation is also performed when the initial ink is loaded into the head or when the ink is used after being stopped for a long time, and the deteriorated ink solidified by increasing the viscosity is sucked and removed.

  Specifically, when air bubbles are mixed in the nozzle 251 or the pressure chamber 252 or when the viscosity of the ink in the nozzle 251 exceeds a certain level, ink is ejected from the nozzle 251 in the preliminary ejection for operating the piezoelectric element 268. become unable. In such a case, the pump 297 sucks ink or thickened ink in which bubbles in the pressure chamber 252 are mixed by applying a cap 294 to the nozzle surface 250A of the head 250.

  However, since the above suction operation is performed on the entire ink in the pressure chamber 252, the amount of ink consumed is large. Therefore, when the increase in viscosity is small, it is preferable to perform preliminary discharge as much as possible. Preferably, the inside of the cap 294 is divided into a plurality of areas corresponding to the nozzle rows by a partition wall, and each of the partitioned areas can be selectively sucked by a selector or the like.

  In this embodiment, a full-line head is exemplified, but the scope of application of the present invention is not limited to this, and a short head having a nozzle row having a length shorter than the width of the recording medium is arranged in the width direction of the recording medium. The present invention is also applicable to a serial type (shuttle scan type) head that performs printing in the width direction of the recording medium while scanning.

  In the above-described embodiment, the method for manufacturing the nozzle plate of the inkjet head has been described. However, the applicable range of the nozzle plate manufactured by the method for manufacturing a nozzle plate according to the present invention is not limited to the above-described ink jet recording apparatus. It can be applied to droplet ejection heads used in various droplet ejection devices that eject (spray) liquids, such as industrial precision coating devices, resist printing devices, wiring drawing devices for electronic circuit boards, and dyeing devices. .

The block diagram which shows an example of the exposure apparatus used for the manufacturing method of the nozzle plate which concerns on embodiment of this invention Enlarged view of the exposure part of the exposure equipment Plan view showing an example of arrangement of light receiving sensors attached to the stage Configuration diagram of illumination unit used in exposure apparatus Diagram showing the light source spectrum of an ultra-high pressure mercury lamp The graph which shows the transmittance | permeability characteristic (incident angle dependence) of the optical interference film used for the exposure mask of this example The block diagram which shows the example of the inclination rotation mechanism in exposure apparatus Explanatory drawing showing manufacturing process of exposure mask Process drawing which showed the manufacturing process of the nozzle plate which concerns on 1st Embodiment Explanatory drawing illustrating a configuration in which a resist is attached to an exposure mask Explanatory drawing of the exposure process in 1st Embodiment Explanatory drawing of the manufacturing process of the nozzle plate which concerns on 1st Embodiment. Explanatory drawing of exposure process when adding counterbore and trap groove Explanatory drawing of manufacturing process of nozzle plate with counterbore and trap groove Plan view of the nozzle plate shown in FIG. Explanatory drawing of the exposure process applied to the manufacturing process of the nozzle plate which concerns on 2nd Embodiment. Explanatory drawing of manufacturing process of nozzle plate with counterbore and trap groove Process drawing which showed the manufacturing process of the nozzle plate which concerns on 3rd Embodiment Explanatory drawing of the manufacturing process of the nozzle plate which concerns on 3rd Embodiment. Light reception monitor block diagram Process diagram of exposure process including corrected exposure Plan view showing an example of mask pattern arrangement 1 is an overall configuration diagram of an ink jet recording apparatus according to an embodiment of the present invention. Plan view of the main part around the printing unit of an inkjet recording apparatus Plane perspective view showing structural example of head Sectional view showing an example of the internal structure of the head Schematic configuration diagram of an ink supply system in an ink jet recording apparatus

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Exposure apparatus, 12 ... Light source, 14 ... Irradiation optical system, 16 ... Immersion container, 18 ... Transmission correction plate, 20 ... Stage, 22 ... Exposure mask, 24 ... Resist, 28 ... Rotary axis, 32 ... Transparent substrate, 34 ... Optical interference film, 36 ... Opaque film, 38 ... Opening area, 40 ... Opening area, 48 ... Light receiving sensor, 50 ... Nozzle plate forming part, 52 ... Light receiving monitor part, 60 ... Illumination unit, 70 ... Pure water, 106 ... Gas layer, 108 ... Liquid layer, 115 ... Nozzle plate, 118 ... Wide angle taper nozzle with constriction, 120 ... Semi-transmissive area, 121 ... Semi-transmissive area, 122 ... Exposure mask, 150 ... Nozzle plate, 152 ... Counterbore part, 130 ... Trap groove, 140 ... concave portion, 170 ... reflective member, 194 ... non-permeable film, 210 ... inkjet recording apparatus, 212K, 212C, 212M, 212Y ... head, 50 ... head, 251 ... nozzle

Claims (17)

An optical interference layer having a characteristic that the transmittance increases as the incident angle of the light of the wavelength increases, and a material that does not transmit the light of the wavelength on one side surface of the transmission substrate that transmits the light of the wavelength used for exposure Using an exposure mask that is laminated with a light blocking layer,
A photosensitive material attaching step of attaching a negative photosensitive material to the surface of the exposure mask on which the light blocking layer is formed;
The photosensitive material is adhered while irradiating light having the wavelength from the surface on the transmission substrate side of the exposure mask to which the photosensitive material is adhered at a first incident angle relatively small with respect to the transmission substrate. Rotating the exposed exposure mask, the light incident on the photosensitive material through the first light passage region formed in the light interference layer and the second light passage region formed in the light blocking layer The photosensitive material is exposed to light, and the light transmitted through the photosensitive material is reflected on the back surface side of the photosensitive material, and the photosensitive material is exposed to the reflected light, thereby forming the first tapered shape. A first exposure step for forming a photosensitive region portion having:
The photosensitive material is adhered while irradiating light of the wavelength at a relatively large second incident angle with respect to the transmissive substrate from the surface on the transmissive substrate side of the exposure mask to which the photosensitive material is adhered. The exposed exposure mask is rotated, and the photosensitive material is exposed to light incident on the photosensitive material through the light interference layer and the second light passage region, while the light transmitted through the photosensitive material is exposed. A second exposure step of suppressing a reflection from the back side of the photosensitive material and forming a photosensitive region portion having a second tapered shape opposite to the first tapered shape ;
A development step of performing development processing after the first exposure step and the second exposure step;
A metal film forming step of forming a metal film corresponding to the nozzle plate using an electroforming method using the photosensitive material pattern remaining by the development processing,
The first exposure step is performed in a first medium having a first refractive index, and reflects light transmitted through the photosensitive material at an interface between the photosensitive material and the first medium. Then, while using the reflected light for the photosensitive material photosensitive,
The second exposure step is performed in a second medium having a second refractive index larger than the first refractive index, and the photosensitive material of the light transmitted through the photosensitive material and the second A method for producing a nozzle plate, wherein reflection at the interface with the medium is reduced . It said first medium is a gas, method of manufacturing a nozzle plate according to claim 1, wherein the second medium is a liquid. An optical interference layer having a characteristic that the transmittance increases as the incident angle of the light of the wavelength increases, and a material that does not transmit the light of the wavelength on one side surface of the transmission substrate that transmits the light of the wavelength used for exposure Using an exposure mask that is laminated with a light blocking layer,
A photosensitive material attaching step of attaching a negative photosensitive material to the surface of the exposure mask on which the light blocking layer is formed;
The photosensitive material is adhered while irradiating light having the wavelength from the surface on the transmission substrate side of the exposure mask to which the photosensitive material is adhered at a first incident angle relatively small with respect to the transmission substrate. Rotating the exposed exposure mask, the light incident on the photosensitive material through the first light passage region formed in the light interference layer and the second light passage region formed in the light blocking layer The photosensitive material is exposed to light, and the light transmitted through the photosensitive material is reflected on the back surface side of the photosensitive material, and the photosensitive material is exposed to the reflected light, thereby forming the first tapered shape. A first exposure step for forming a photosensitive region portion having:
The photosensitive material is adhered while irradiating light of the wavelength at a relatively large second incident angle with respect to the transmissive substrate from the surface on the transmissive substrate side of the exposure mask to which the photosensitive material is adhered. The exposed exposure mask is rotated, and the photosensitive material is exposed to light incident on the photosensitive material through the light interference layer and the second light passage region, while the light transmitted through the photosensitive material is exposed. A second exposure step of suppressing a reflection from the back side of the photosensitive material and forming a photosensitive region portion having a second tapered shape opposite to the first tapered shape;
A development step of performing development processing after the first exposure step and the second exposure step;
A metal film forming step of forming a metal film corresponding to the nozzle plate using an electroforming method using the photosensitive material pattern remaining by the development processing,
While providing a reflecting member on the back side of the photosensitive material attached to the exposure mask, the relative position of the reflecting member with respect to the photosensitive material can be changed,
In the first exposure step, the reflecting member is disposed close to the photosensitive material, and the light transmitted through the photosensitive material is reflected by the reflecting member, whereby the reflected light is reflected on the photosensitive material. While used for photosensitivity
In the second exposure step, the reflecting member is disposed away from the photosensitive material so that the light transmitted through the photosensitive material does not hit the reflecting member, and reflection by the reflecting member is suppressed. The manufacturing method of the nozzle plate. The method for manufacturing a nozzle plate according to claim 3, wherein the first exposure step and the second exposure step are performed in pure water. The metal film forming step includes a liquid repellent plating treatment step for forming a liquid repellent plating layer,
A Ni electroforming step of depositing nickel (Ni) on the liquid repellent plating layer;
5. The method of manufacturing a nozzle plate according to claim 1, wherein: The light blocking layer has a second semi-transmissive region corresponding to a groove formed on the discharge surface side of the nozzle plate,
A photosensitive region portion corresponding to the shape of the groove is formed by light transmitted through the second semi-transmissive region in the second exposure step,
In the Ni electroforming process, a Ni layer is deposited on the photosensitive region corresponding to the shape of the groove of the photosensitive material pattern, thereby forming a groove having a concave surface on the side opposite to the groove. The method for manufacturing a nozzle plate according to claim 5 . An optical interference layer having a characteristic that the transmittance increases as the incident angle of the light of the wavelength increases, and a material that does not transmit the light of the wavelength on one side surface of the transmission substrate that transmits the light of the wavelength used for exposure Using an exposure mask that is laminated with a light blocking layer,
A photosensitive material attaching step of attaching a positive photosensitive material to the surface of the exposure mask on which the light blocking layer is formed;
The photosensitive material is adhered while irradiating light having the wavelength from the surface on the transmission substrate side of the exposure mask to which the photosensitive material is adhered at a first incident angle relatively small with respect to the transmission substrate. Rotating the exposed exposure mask, the light incident on the photosensitive material through the first light passage region formed in the light interference layer and the second light passage region formed in the light blocking layer The photosensitive material is exposed to light, and the light transmitted through the photosensitive material is reflected on the back surface side of the photosensitive material, and the photosensitive material is exposed to the reflected light, thereby forming the first tapered shape. A first exposure step for forming a photosensitive region portion having:
The photosensitive material is adhered while irradiating light of the wavelength at a relatively large second incident angle with respect to the transmissive substrate from the surface on the transmissive substrate side of the exposure mask to which the photosensitive material is adhered. The exposed exposure mask is rotated, and the photosensitive material is exposed to light incident on the photosensitive material through the light interference layer and the second light passage region, while the light transmitted through the photosensitive material is exposed. A second exposure step of suppressing a reflection from the back side of the photosensitive material and forming a photosensitive region portion having a second tapered shape opposite to the first tapered shape;
A development step of performing development processing after the first exposure step and the second exposure step;
  Forming a nozzle plate composed of a photosensitive material remaining by the development process,
The first exposure step is performed in a first medium having a first refractive index, and reflects light transmitted through the photosensitive material at an interface between the photosensitive material and the first medium. Then, while using the reflected light for the photosensitive material photosensitive,
  The second exposure step is performed in a second medium having a second refractive index larger than the first refractive index, and the photosensitive material of the light transmitted through the photosensitive material and the second A method for producing a nozzle plate, wherein reflection at the interface with the medium is reduced. 8. The method of manufacturing a nozzle plate according to claim 7, wherein the first medium is a gas, and the second medium is a liquid. An optical interference layer having a characteristic that the transmittance increases as the incident angle of the light of the wavelength increases, and a material that does not transmit the light of the wavelength on one side surface of the transmission substrate that transmits the light of the wavelength used for exposure Using an exposure mask that is laminated with a light blocking layer,
A photosensitive material attaching step of attaching a positive photosensitive material to the surface of the exposure mask on which the light blocking layer is formed;
The photosensitive material is adhered while irradiating light having the wavelength from the surface on the transmission substrate side of the exposure mask to which the photosensitive material is adhered at a first incident angle relatively small with respect to the transmission substrate. Rotating the exposed exposure mask, the light incident on the photosensitive material through the first light passage region formed in the light interference layer and the second light passage region formed in the light blocking layer The photosensitive material is exposed to light, and the light transmitted through the photosensitive material is reflected on the back surface side of the photosensitive material, and the photosensitive material is exposed to the reflected light, thereby forming the first tapered shape. A first exposure step for forming a photosensitive region portion having:
The photosensitive material is adhered while irradiating light of the wavelength at a relatively large second incident angle with respect to the transmissive substrate from the surface on the transmissive substrate side of the exposure mask to which the photosensitive material is adhered. The exposed exposure mask is rotated, and the photosensitive material is exposed to light incident on the photosensitive material through the light interference layer and the second light passage region, while the light transmitted through the photosensitive material is exposed. A second exposure step of suppressing a reflection from the back side of the photosensitive material and forming a photosensitive region portion having a second tapered shape opposite to the first tapered shape;
A development step of performing development processing after the first exposure step and the second exposure step;
  Forming a nozzle plate composed of a photosensitive material remaining by the development process,
While providing a reflecting member on the back side of the photosensitive material attached to the exposure mask, the relative position of the reflecting member with respect to the photosensitive material can be changed,
In the first exposure step, the reflecting member is disposed close to the photosensitive material, and the light transmitted through the photosensitive material is reflected by the reflecting member, whereby the reflected light is reflected on the photosensitive material. While used for photosensitivity
In the second exposure step, the reflecting member is disposed away from the photosensitive material so that the light transmitted through the photosensitive material does not hit the reflecting member, and reflection by the reflecting member is suppressed. The manufacturing method of the nozzle plate. The method for manufacturing a nozzle plate according to claim 9, wherein the first exposure step and the second exposure step are performed in pure water. A protective film forming step of depositing a protective film on at least the nozzle inner surface of the nozzle plate formed of photosensitive material remaining by pre Symbol development,
A liquid repellent film forming step of depositing a liquid-repellent film on the discharge surface of the nozzle plate is released the exposure mask or al peeling,
The method for manufacturing a nozzle plate according to any one of claims 7 to 10, wherein A groove forming exposure mask having a third semi-transmissive region having a width narrower than the nozzle inflow side opening is disposed on the photosensitive material side of the exposure mask to which the photosensitive material is adhered, and the groove forming exposure is performed. Including a third exposure step of exposing the photosensitive material by light transmitted through the third semi-transmissive region by irradiating the mask with light,
12. The nozzle plate according to claim 7, wherein the third exposure step forms a photosensitive area corresponding to a groove in which the surface on the nozzle inflow side is recessed in a concave shape. Manufacturing method. The light blocking layer has a first transflective region in contact with the second light passage region so as to surround the second light passage region, and the second exposure step includes the first light transmission layer. The method of manufacturing a nozzle plate according to any one of claims 1 to 12 , wherein a stepped photosensitive region corresponding to the counterbore is formed by light transmitted through one semi-transmissive region. The light blocking layer has a second semi-transmissive region corresponding to a groove formed on the discharge surface side of the nozzle plate,
The light transmitted through the second translucent areas in the second exposure step, in any one of claims 1 to 13, characterized in that the photosensitive area portion corresponding to the shape of the groove is formed The manufacturing method of the nozzle plate of description. The exposure mask is provided with a light receiving monitor unit provided with a dummy mask pattern in a region other than the nozzle plate forming unit,
A light receiving sensor for receiving light transmitted through the photosensitive material through the dummy mask pattern is disposed on a stage for fixing the exposure mask to which the photosensitive material is adhered, and among the light receiving regions of the light receiving sensor. In the second exposure step, there is provided a shielding means for shielding the light that passes through a dummy light passage area corresponding to the first light passage area from entering the light receiving sensor,
The nozzle plate according to any one of claims 1 to 14 , wherein the amount of exposure is controlled based on a monitoring result while monitoring the transmitted light of the photosensitive material by the light receiving sensor. Method. A discharge lamp is used as a light source used in the first exposure step and the second exposure step, and the second tapered photosensitive region in the second exposure step of the light source spectrum of the discharge lamp. The light from which the longer wavelength side than the wavelength that contributes to the formation of the portion is removed is applied to the exposure mask during the first exposure step and the second exposure step. The method for producing a nozzle plate according to any one of 15 . Wherein the exposure mask is produced in the nozzle plate according to any one of claims 1 to 16, characterized in that the mask pattern of the nozzle plate forming regions corresponding to the plurality of nozzle plates are arranged with rotational symmetry Method.

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