JP2006323110A - Method for forming three-dimensional structure, method for forming spacer for liquid crystal display element using this forming method, transparent substrate with three-dimensional structure, and uv irradiation system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To establish a method for selectively forming a three-dimensional structure at the predetermined position of a transparent substrate and to provide a transparent substrate on which a three-dimensional structure is selectively formed at a predetermined position. <P>SOLUTION: After a negative photosensitive resin 7 is applied to a transparent substrate 8 having a light shielding part 20 formed thereon, the transparent substrate 8 is irradiated with UV rays from the opposite surface side to the surface coated with the negative photosensitive resin 7. Thereby, the negative photosensitive resin 7 in a translucent region 9 being the region not shielded from UV rays by the light shielding part 20 is cured. Then beads 12 are sprayed on the surface of the substrate 8 where the negative photosensitive resin 7 is applied, and the substrate is irradiated with UV rays from the surface where the negative photosensitive resin 7 is applied so as to cure the uncured negative photosensitive resin 9 present on the light shielding region 6 being the region shielded by the light shielding part 20 to fix the beads 12 disposed only on the light shielding region 6 to the transparent substrate 8. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a transparent substrate on which a three-dimensional structure is formed and a method for forming the three-dimensional structure, and more particularly to a light shielding region of a liquid crystal display device using a method for forming a three-dimensional structure on a transparent substrate. The present invention relates to a method of selectively forming spacers and an ultraviolet irradiation system that can be suitably used in the forming method.

  In recent years, liquid crystal display elements are widely used in various electronic devices such as personal computers, televisions, electronic notebooks, and mobile phones. In general, a liquid crystal display element is formed by bonding two insulating substrates made of a transparent glass substrate or the like so as to face each other, and disposing a liquid crystal layer made of a liquid crystal composition in the gap between the two insulating substrates, It is comprised so that a liquid-crystal layer may be sealed with the sealing member which bonds the peripheral part of the said insulating substrates.

  Usually, a liquid crystal driving element such as a thin film transistor (TFT) is formed on one of the two insulating substrates, and a color filter (CF) is formed on the other. If there is unevenness in the gap between the insulating substrates (hereinafter referred to as “cell gap”), that is, the thickness of the liquid crystal layer, unevenness in display occurs in the liquid crystal display element. Therefore, it is necessary to keep the cell gap uniform with high precision throughout the liquid crystal layer.

  Usually, the cell gap is as narrow as about 2 to 5 μm, and in order to keep the cell gap uniform, for example, plastic beads having a substantially uniform diameter are sprayed on the insulating substrate, and the plastic beads are dispersed on the insulating substrate. Is done. That is, there is a method of using this plastic bead as a so-called spacer for maintaining the cell gap uniformly.

  However, in the above method, the plastic beads are randomly dispersed in the sealing member, and it is difficult to control the dispersion, so that the density of the distribution of the plastic beads is locally generated on the insulating substrate. In particular, if a large number of spacers are aggregated in a region that transmits light from a light source and is used for display (hereinafter referred to as a “translucent region”), the spacer formed in the translucent region when the liquid crystal display element is used. If the spacer is transparent, it will be observed as a bright spot, and if the spacer is black, it will be observed as a black spot, resulting in display unevenness due to light leakage and the like, resulting in a problem of deterioration in display quality.

  In view of this, a method has been proposed in which a spacer is selectively formed in a region that does not transmit light (hereinafter referred to as a “light-shielding region”). If a spacer can be arranged in the light shielding region, display unevenness caused by the spacer can be suppressed, so that a liquid crystal display element with good display quality can be provided.

  As a method for selectively forming the spacer in the light shielding region as described above, for example, Patent Document 1 discloses a method in which a spacer made of a photoresist is formed in the light shielding region using photolithography. However, according to the above method, when forming the spacer, in order to stably apply the photoresist, the photoresist is applied more than necessary, and as a result, the amount of the photoresist applied increases and the cost increases. There was a problem of becoming higher.

  Therefore, Patent Document 2 proposes a method in which a curable resin composition is selectively ejected onto a light shielding region by an ink jet method, and the ejected resin composition is cured to form a spacer.

  Further, in Patent Document 3, an adhesive is applied on a substrate by an ink jet method, then beads are dispersed to attach the beads to the adhesive, and the beads not attached to the adhesive are removed from the substrate. A method of forming a spacer is disclosed.

As described above, since the inkjet method does not require a mask for forming a spacer in a predetermined region, the spacer can be formed at a lower cost than the case where the spacer is formed by photolithography.
JP-A-6-175133 (released on June 24, 1994) JP 2001-83525 A (published on March 30, 2001) JP 2001-83906 A (published on March 30, 2001)

  However, in the configuration of Patent Document 2, when the curable resin composition or the like is ejected to a predetermined position (for example, a light shielding region) of the substrate using the inkjet method, the curable resin composition or the like protrudes from the predetermined position. Cause the problem of end.

  Normally, in the above-described ink jet method, the nozzle diameter cannot be reduced and the resin discharge amount (volume) is reduced in order to prevent clogging of the resin in the vicinity of the nozzle portion of the ink jet head that discharges the resin (ink). I can't. Therefore, the volume of the discharged resin is approximately 1 pl or more. In addition, in order to ensure a stable discharge operation, the present situation is that a discharge amount of 4 to 5 pl or more is required.

  However, since the light-shielding area is usually as narrow as about 20 to 30 μm compared to the above-mentioned 4 to 5 pl resin discharge amount, it is difficult to dispose the applied resin in the light-shielding area. For this reason, there is a possibility that the resin may protrude into the light transmitting region adjacent to the light shielding region. As a result, the spacer formed by curing the resin protrudes from the light transmitting region. As a result, when the liquid crystal display element is used, display unevenness due to light leakage or the like occurs, and the display quality of the liquid crystal display element deteriorates.

  A similar problem occurs in the method of applying an adhesive on a substrate by the inkjet method described in Patent Document 3. That is, when the adhesive is applied onto the substrate using the ink jet method, the amount of ejection is larger than the area of the light-shielding region to be applied, so that the adhesive application region is expanded and the adhesive is also applied to the light-transmitting region. Will be.

  For this reason, if the beads are dispersed after the step of discharging the adhesive, the beads are also arranged on the adhesive applied to the translucent region, that is, the spacers made of beads are arranged on the translucent region. It will be.

  As described above, the ink jet method generally has a feature that a small amount of resin can be ejected. However, for example, it is not sufficient for use in forming the spacer for the liquid crystal display element, and the spacer is selectively provided in the light shielding region. The problem is that it is difficult to form.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to realize a method for selectively forming a three-dimensional structure only in a light-shielding region of a transparent substrate, and to use the formation method. A transparent substrate and a method for selectively forming a spacer for a liquid crystal display element selectively only in a light-shielding region of the transparent substrate for a liquid crystal display element by using the formation method. Another object of the present invention is to realize an apparatus for irradiating ultraviolet rays that can be suitably used in the above-described forming method.

  In order to solve the above problems, a method for forming a three-dimensional structure according to the present invention is a method for forming a three-dimensional structure on a light-shielding portion formed on a transparent substrate. An application step of applying to the transparent substrate, and a surface of the transparent substrate facing away from the surface to which the negative photosensitive resin is applied, are irradiated with ultraviolet rays through the transparent substrate and are not shielded by the light shielding portion. A first curing step of curing the negative photosensitive resin applied to the region, a spraying step of spraying beads on the surface of the transparent substrate coated with the negative photosensitive resin, and a negative in the transparent substrate A second photosensitive resin is fixed to the transparent substrate by irradiating ultraviolet rays from the side coated with the photosensitive resin to cure the negative photosensitive resin in the region that has not been cured in the first curing step. Curing process and the second curing process It is characterized by having a removal step of removing in not fixed to the transparent substrate beads from the transparent substrate.

  According to said structure, negative photosensitive resin is apply | coated to the transparent substrate provided with the light-shielding part.

  Here, the negative photosensitive resin means a resin that is cured by light having a specific wavelength. For convenience of explanation, the surface of the transparent substrate on which the negative photosensitive resin is applied is referred to as the upper surface, and the surface opposite to the upper surface of the transparent substrate is referred to as the lower surface.

  Next, ultraviolet rays are irradiated from the lower surface side of the transparent substrate. Accordingly, the negative photosensitive resin existing in a light-shielded area (hereinafter referred to as a light-shielded area) using the light-shielding part as a mask is not irradiated with ultraviolet rays and is not shielded by the light-shielding part (hereinafter referred to as a light-transmitting area). The negative photosensitive resin present in the substrate is irradiated with ultraviolet rays. Therefore, only the negative photosensitive resin existing in the light transmitting region can be cured. That is, the negative photosensitive resin present in the light shielding region is not irradiated with ultraviolet rays and can maintain the same state as when applied.

  Next, beads are dispersed from the upper surface side of the transparent substrate, and then ultraviolet rays are irradiated from the upper surface side of the transparent substrate.

  Thereby, the negative photosensitive resin existing in the light shielding region is cured. Further, when the negative photosensitive resin existing in the light shielding region is cured, the beads that are in contact with the negative photosensitive resin are fixed to the transparent substrate and cured. Therefore, the negative photosensitive resin acts as an adhesive that fixes the beads to the transparent substrate. At this time, since the negative photosensitive resin in the translucent region is cured by the irradiation of ultraviolet rays from the lower surface of the transparent substrate, the three-dimensional structure dispersed in the translucent region is not fixed. That is, the beads are fixed only in the light shielding region of the transparent substrate.

  If the unfixed beads are removed, the beads are selectively arranged in the light shielding region.

  According to the above configuration, even if the negative photosensitive resin protrudes from the light shielding region and is applied to the light transmitting region, the negative photosensitive resin applied to the light transmitting region is first applied before the beads are dispersed. Therefore, the beads are not fixed to the light-transmitting region. Therefore, beads can be selectively arranged only in the light shielding region. Therefore, a three-dimensional structure made of beads can be formed only in the light shielding region. That is, it is possible to provide a forming method for selectively forming a three-dimensional structure in the light shielding region.

  The method for forming a three-dimensional structure according to the present invention is a method for forming a three-dimensional structure on a light-shielding portion formed on a transparent substrate, the coating step applying a positive photosensitive resin to the transparent substrate; In the transparent substrate, the positive photosensitive resin applied to the area not shielded by the light-shielding part by irradiating ultraviolet rays through the transparent substrate from the side facing away from the surface coated with the positive photosensitive resin. A solubilization step for solubilizing the resin, a removal step for removing the positive photosensitive resin solubilized in the solubilization step with a solvent, and a step for baking the positive photosensitive resin not removed in the removal step It is characterized by having.

  According to said structure, positive type photosensitive resin is apply | coated to the transparent substrate provided with the light-shielding part.

  Here, the positive photosensitive resin means a resin that is solubilized by light having a specific wavelength. For convenience of explanation, the surface of the transparent substrate on which the positive photosensitive resin is applied is referred to as the upper surface, and the surface opposite to the upper surface of the transparent substrate is referred to as the lower surface.

  Next, ultraviolet rays are irradiated from the lower surface side of the transparent substrate. Thereby, ultraviolet rays are not irradiated to the positive photosensitive resin existing in the light shielding region, and ultraviolet rays are irradiated only to the positive photosensitive resin existing in the light transmitting region. Therefore, only the positive photosensitive resin existing in the light transmitting region can be solubilized. That is, the positive photosensitive resin present in the light shielding region is not irradiated with ultraviolet rays and can maintain the same state as when applied.

  Then, by removing the solubilized positive photosensitive resin with a solvent, the positive photosensitive resin can be selectively left in the light shielding region. That is, it is possible to form a three-dimensional structure made of a positive photosensitive resin only in the light shielding region of the transparent substrate. Therefore, even if the positive photosensitive resin protrudes from the light shielding region and is applied to the light transmitting region, the three-dimensional structure can be selectively arranged only in the light shielding region.

  In addition, by baking the positive photosensitive resin in the light shielding region, the positive photosensitive resin can be further adhered and fixed to the transparent substrate. Further, the positive photosensitive resin can be cured. Further, the positive photosensitive resin can be shrunk by baking. Thereby, the shrinkage | contraction state of positive photosensitive resin is controllable by changing conditions, such as temperature and time at the time of baking. That is, the formed three-dimensional structure can be controlled to a desired height.

  Further, according to the above configuration, patterning can be easily performed without using an expensive exposure apparatus used for lithography, while forming a three-dimensional structure by patterning a positive photosensitive resin on a transparent substrate. It is possible to form a three-dimensional structure at low cost.

  In the method for forming a three-dimensional structure according to the present invention, it is preferable to use an inkjet method for the coating step.

  According to the above configuration, since a small droplet of a negative photosensitive resin or a positive photosensitive resin is ejected using an inkjet method, unlike a method of applying a resin to the entire surface of the substrate such as a spin coating method, a predetermined photosensitive resin is applied. A negative photosensitive resin or a positive photosensitive resin can be applied to the position. Accordingly, the negative photosensitive resin or the positive photosensitive resin is not wasted, and the manufacturing cost can be reduced. Furthermore, since a negative photosensitive resin or a positive photosensitive resin can be easily applied at a predetermined position, a three-dimensional structure can be stably formed.

  In the method for forming a three-dimensional structure according to the present invention, the coating step is performed by using an inkjet method so that the central portion of the positive photosensitive resin is disposed in a region shielded from light by the light shielding portion. It is preferable to include discharging a type photosensitive resin.

  According to the above configuration, when the positive photosensitive resin is ejected using the inkjet method, the positive photosensitive resin is ejected so that the central portion of the positive photosensitive resin is disposed in the light shielding region. . As a result, even if the portion of the positive photosensitive resin that protrudes from the light shielding region is removed, the height of the three-dimensional structure formed in the light shielding region is made equal as long as the discharge amount of the positive photosensitive resin is the same. can do. Therefore, it is possible to form a three-dimensional structure having a predetermined height with good reproducibility. Note that “the central part of the positive photosensitive resin” means that when the positive photosensitive resin is discharged onto the transparent substrate, from the surface where the positive photosensitive resin is formed on the transparent substrate, The part that rises high.

  A method for forming a spacer for a liquid crystal display element according to the present invention is a three-dimensional method for controlling the thickness of a liquid crystal layer on a transparent substrate on which a light-shielding portion is formed using the above three-dimensional structure forming method. It is characterized by forming a spacer which is a structure.

  According to said structure, the spacer which is a three-dimensional structure for controlling the thickness of a liquid crystal layer can be selectively formed in the light-shielding area light-shielded by the light-shielding part formed in the transparent substrate. It becomes. Accordingly, since no spacer is formed in the light-transmitting region, display unevenness due to the spacer can be prevented in the liquid crystal display element.

  In the method for forming a spacer for a liquid crystal display element according to the present invention, the light shielding part is preferably a metal wiring of a liquid crystal driving element.

  According to said structure, using the said formation method of a three-dimensional structure, the spacer which is a three-dimensional structure can be formed by using the metal wiring of the liquid crystal drive element formed on the said transparent substrate as a light-shielding part. it can. Therefore, in order to form a three-dimensional structure, a new light shielding region is not required, and a large light transmitting region of the liquid crystal display element can be secured. In other words, since the aperture ratio of the light-transmitting region can be increased, high-precision display can be performed in the liquid crystal display element.

  The transparent substrate according to the present invention includes a light-shielding portion and a three-dimensional structure, and a negative photosensitive resin is applied to a light-shielding region that is shielded by the light-shielding portion, and the negative photosensitive resin is interposed therebetween. Thus, a three-dimensional structure is formed only in the light shielding region.

  According to said structure, the three-dimensional structure is formed only in the light-shielding area | region of a transparent substrate. That is, since the three-dimensional structure is not formed in the translucent region, for example, the transparent substrate can be provided as a transparent substrate on which a spacer for a liquid crystal display element is formed.

  The transparent substrate according to the present invention includes a light shielding portion and a three-dimensional structure made of a positive photosensitive resin, and the three-dimensional structure has a positive photosensitive property in a light shielding region shielded by the light shielding portion. It is characterized by being formed by arranging the central part of the resin.

  According to the above configuration, the positive photosensitive resin is formed in the light shielding region such that the central portion of the positive photosensitive resin is disposed in the light shielding region when ejected. Accordingly, the heights of the formed three-dimensional structures are equal to each other even if a plurality of three-dimensional structures are formed. Therefore, for example, the transparent substrate can be provided as a substrate for a liquid crystal display element in which spacers having the same height are fixed.

  In the ultraviolet irradiation system according to the present invention, an ultraviolet irradiation device that irradiates a substrate to be processed with ultraviolet rays, a reflection device that reflects the ultraviolet rays and irradiates the substrate to be processed, and between the ultraviolet irradiation device and the reflection device. A transfer means for transferring the substrate to be processed, and further comprising a switching means for switching the reflection device between a state in which the substrate to be processed is irradiated with ultraviolet rays and a state in which the substrate to be processed is not irradiated with ultraviolet rays. It is a feature.

  According to said structure, the ultraviolet irradiation apparatus which irradiates a to-be-processed substrate with an ultraviolet-ray, the reflection apparatus which reflects the said ultraviolet-ray and irradiates the said to-be-processed substrate, and between a said ultraviolet irradiation apparatus and the said reflection apparatus, it is covered. Transporting means for transporting the processing substrate. Thereby, for example, the surface of the substrate to be processed and the surface facing away from the surface of the substrate to be processed by the ultraviolet rays irradiated from the ultraviolet irradiation device and the ultraviolet rays reflected and irradiated by the ultraviolet reflection device. It is also possible to irradiate the both surfaces with ultraviolet rays. And since it can convey, it becomes easy to irradiate a predetermined position with an ultraviolet-ray. Therefore, it is not necessary to arrange the ultraviolet irradiation device on both sides of the transparent substrate, and it is possible to realize an ultraviolet irradiation system that is inexpensive and realizes space saving.

  Further, according to the above configuration, the reflection device includes switching means for switching between a state in which the substrate to be processed is irradiated with ultraviolet rays and a state in which the substrate to be processed is not irradiated with ultraviolet rays. Thereby, ultraviolet rays can be irradiated from both sides of the substrate to be processed only when desired.

  In the ultraviolet irradiation system according to the present invention, it is preferable that the switching means switches between the two states by rotating the reflection device.

  According to said structure, a reflection apparatus can be rotated by a switching means, and the said both states (Namely, the state which irradiates an ultraviolet-ray to a to-be-processed substrate, and the state which does not irradiate an to-be-processed substrate) can be switched. Therefore, the reflected light can be irradiated to the substrate to be processed by the reflection device only when desired.

  In the ultraviolet irradiation system according to the present invention, it is preferable that the switching means includes a light shielding member that shields the reflection device.

  According to said structure, since the switching means is equipped with the light-shielding member which light-shields a reflection apparatus, it can irradiate a to-be-processed substrate with a reflection apparatus only when desired.

  In the ultraviolet irradiation system according to the present invention, it is preferable that the switching means moves the reflecting device to a position where the ultraviolet light is irradiated and a position where the ultraviolet light is not irradiated.

  According to the above configuration, the reflection device can be irradiated with the reflected light by the reflection device only when desired, by moving the reflection device to a position where the ultraviolet light is irradiated and a position where the ultraviolet light is not irradiated. it can.

  As described above, the three-dimensional structure forming method according to the present invention includes a coating step of applying a negative photosensitive resin to the transparent substrate, and a back surface of the transparent substrate on which the negative photosensitive resin is applied. In the first curing step of irradiating ultraviolet rays through the transparent substrate from the facing surface and curing the negative photosensitive resin applied to the region not shielded by the light-shielding portion, and the transparent substrate, A dispersion process of spreading beads on the surface coated with the negative photosensitive resin, and curing in the first curing process by irradiating ultraviolet rays from the surface of the transparent substrate coated with the negative photosensitive resin. A second curing step in which the negative photosensitive resin in the area that was not cured is cured and the beads are fixed to the transparent substrate; and the beads that are not fixed to the transparent substrate in the second curing step are removed from the transparent substrate. Removing step It is formed.

  In addition, as described above, the method for forming a three-dimensional structure according to the present invention includes a coating step in which a positive photosensitive resin is applied to the transparent substrate, and a surface on which the positive photosensitive resin is applied in the transparent substrate. In the solubilization step of solubilizing the positive photosensitive resin applied to the region not shielded by the light-shielding part by irradiating ultraviolet rays through the transparent substrate from the side facing away from the surface, and the solubilization step This is a configuration having a removal step of removing the solubilized positive photosensitive resin with a solvent and a step of baking the positive photosensitive resin not removed in the removal step.

  As described above, the method for forming a spacer for a liquid crystal display element according to the present invention controls the thickness of the liquid crystal layer on the transparent substrate on which the light-shielding portion is formed, using the above three-dimensional structure forming method. It is the structure which forms the spacer which is a three-dimensional structure for doing.

  This makes it possible to selectively form a spacer, which is a three-dimensional structure for controlling the thickness of the liquid crystal layer, in a light shielding region that is shielded from light by the light shielding portion formed on the transparent substrate. Accordingly, since no spacer is formed in the light-transmitting region, display unevenness due to the spacer can be prevented in the liquid crystal display element.

  Therefore, even if a negative photosensitive resin or a positive photosensitive resin is applied to a region that is not shielded by the light shielding portion (translucent region), a three-dimensional structure is not formed in the region. In other words, there is an effect that the three-dimensional structure can be selectively formed only in the region shielded by the light shielding portion.

  As described above, in the transparent substrate according to the present invention, the negative photosensitive resin is applied to the light shielding region that is shielded by the light shielding unit, and the three-dimensional structure is applied only to the light shielding region through the negative photosensitive resin. It is the structure in which the thing is formed.

  In addition, as described above, the transparent substrate according to the present invention is formed by arranging the central portion of the positive photosensitive resin in the light shielding region where the three-dimensional structure is shielded by the light shielding portion. It is the composition which is.

  Therefore, since the three-dimensional structure is not formed in the light-transmitting region, for example, the transparent substrate can be provided as a transparent substrate on which spacers for liquid crystal display elements are formed.

  Further, as described above, the ultraviolet irradiation system according to the present invention further includes switching means for switching the reflecting device between a state in which the substrate to be processed is irradiated with ultraviolet rays and a state in which the substrate to be processed is not irradiated with ultraviolet rays. It is a configuration.

  Therefore, the ultraviolet rays from the ultraviolet irradiation device can be reflected by the reflection device, and the reflected ultraviolet rays can be easily irradiated to a predetermined place of the substrate to be processed. Therefore, there is an effect that it can be suitably used when forming a three-dimensional structure on a transparent substrate.

[Embodiment 1]
An embodiment of the present invention will be described below with reference to FIGS.

  FIG. 3 is a plan view showing a schematic configuration of one picture element on a transparent substrate (TFT substrate) on which a thin transistor (TFT) as a liquid crystal driving element is formed. Among the reference numerals attached to each member in the figure, 1 is a drain electrode, 2 is a pixel electrode, 3 is a gate wiring, 4 is a source wiring, 5 is a capacitor wiring, 8 is a transparent substrate, 12 is a bead, Reference numerals 19 indicate TFTs.

  As a configuration of one picture element of the TFT substrate 23, one TFT 19 is disposed on the transparent substrate 8, and the picture element electrode 2 is connected to the drain electrode 1 of the TFT 19. The TFT 19, the drain electrode 1, and the pixel electrode 2 are formed so as to surround the gate wiring 3 and the source wiring 4. Further, a capacitor wiring 5 for adjusting the capacitor capacity is arranged so as to cross the pixel electrode 2.

  Here, the gate wiring 3, the source wiring 4, and the capacitor wiring 5 are wirings (metal wirings) made of a conductive material such as metal. That is, the metal wiring serves as a light shielding portion that blocks light.

  Further, beads 12 are fixed on the gate wiring 3, the source wiring 4, and the capacitor wiring 5 through a negative photosensitive resin. That is, the spherical beads 12 are fixed to the light shielding portion. Here, when the liquid crystal display element is manufactured, the beads 12 have a gap (cell gap) between the TFT substrate 23 and another substrate (not shown), that is, the thickness of the liquid crystal layer sandwiched between the TFT substrate 23 and the other substrate. Used as a spacer to adjust (three-dimensional structure). The beads 12 are particles made of silica, alumina, synthetic resin, or the like. The material and shape of the beads 12 are not particularly limited as long as they have mechanical strength as a spacer, and may be cylindrical. Moreover, the color etc. are not specifically limited. The negative photosensitive resin means a resin that is cured by light having a specific wavelength, and the composition of the resin and the like that will be described in detail later.

  The TFT substrate 23 is also provided with a protective film for protecting the TFT 19 and the like, and an alignment film for aligning liquid crystal molecules in a certain direction. Here, for convenience of explanation, FIG. The display is omitted.

  According to said structure, the bead 12 which is a spacer is being fixed only to the light-shielding area | region (metal wiring). Therefore, since there is no spacer in the light transmitting region, that is, the pixel region of the liquid crystal display element, it is possible to prevent display unevenness in the pixel region caused by the spacer. In addition, since the aperture ratio in the light-transmitting region can be maintained large, light can be easily transmitted and high-precision display can be performed.

  In the embodiment described below, in the TFT substrate 23 constituting the liquid crystal display element shown in FIG. 3, the above wiring (for example, the gate wiring 3, the source wiring 4, and the capacitor wiring 5) is used as a light shielding portion. A method for forming a spacer, which is a three-dimensional structure, on the light shielding portion will be described with reference to FIGS. 1 (a) to 1 (e) and FIG. 2.

  Fig.1 (a)-FIG.1 (e) are process drawings of the formation method of the three-dimensional structure which concerns on one Embodiment of this invention. FIG. 2 is a cross-sectional view illustrating a method for forming a three-dimensional structure according to an embodiment of the present invention, and shows the irradiation direction of ultraviolet rays. In the figure, among the reference numerals attached to each member, 6 is a light-shielding region, 7 is a negative photosensitive resin, 8 is a transparent substrate, 9 is a light-transmitting region, 10 is ultraviolet light, 11 is ultraviolet-cured resin, Reference numeral 12 denotes a bead, and 20 denotes a light shielding portion. Here, the light shielding portion 20 is a general term for the gate wiring 3, the source wiring 4, and the capacitor wiring 5 in the TFT substrate 23.

  The method for forming a three-dimensional structure (spacer) of the present embodiment includes an application process, a first curing process, a spraying process, a second curing process, and a removing process.

(Coating process)
FIG. 1A is a plan view and a cross-sectional view showing the configuration of a light shielding region and a light transmitting region of a transparent substrate, and shows a state where a light shielding part is formed on the transparent substrate.

  As shown in FIG. 1A, a resin (hereinafter referred to as a negative type) containing a resin component that is cured by ultraviolet rays from a nozzle of an inkjet head using an inkjet method in a light shielding portion 20 formed on a transparent substrate 8. (Referred to as photosensitive resin) 7 is discharged. That is, the light-sensitive part 20 is covered with the negative photosensitive resin 7, and a thin film made of the negative photosensitive resin 7 is formed on the light-shielding part 20. At this time, it is desirable that the discharged negative photosensitive resin 7 covers only the light shielding part 20, but it may protrude from the light shielding part 20.

  However, since the negative photosensitive resin 7 protruding from the light shielding portion 20 remains (described in detail later), it is desirable to reduce the discharge amount of the negative photosensitive resin 7. Therefore, an ink jet method capable of stably discharging a small amount of resin was adopted as a method for discharging the negative photosensitive resin 7. Note that as long as a small amount of resin can be discharged, the invention is not limited to the ink jet method, and a dispenser or the like can be used.

  Usually, an ink discharge method using an ink jet method uses a piezoelectric material represented by, for example, PZT (lead zirconate titanate), and changes the volume of the ink chamber due to distortion of the piezoelectric material, and the ink is ejected by a mechanical action. A piezo method of discharging from the nozzle. Further, there is a heat conversion method in which bubbles are instantaneously generated by energizing and overheating a heater arranged in the nozzle, and ink is ejected by the pressure. In addition, the discharge method is not particularly limited as long as it can discharge a minute amount of resin. In this embodiment, the negative photosensitive resin 7 is ejected instead of ink using the principle of the ink jet method.

  Further, the driving frequency of the inkjet head for discharging the negative photosensitive resin 7 is not particularly limited. However, if the frequency is specified from 1 kHz to 100 kHz, preferably 10 kHz to 30 kHz, the negative photosensitive resin 7 can be discharged well. Is possible.

  If the discharge amount of the negative photosensitive resin 7 is set to about 1 pl, the nozzle diameter must be narrowed, the nozzle is clogged with the negative photosensitive resin 7, and the negative photosensitive resin 7 does not discharge. It is desirable to set it to about 4 pl to 5 pl or more.

  The distance from the nozzle of the inkjet head to the transparent substrate is desirably set to about 500 μm. If the distance becomes longer, the accuracy of the landing position tends to decrease. Further, if the distance is shortened, the risk of contact between the nozzle and the transparent substrate 8 increases.

  The discharge speed of the negative photosensitive resin 7 may be set to 5 to 10 m / sec when the negative photosensitive resin 7 is discharged from the nozzle. If the discharge speed is slow, the influence of air resistance becomes strong, and the landing accuracy with which the negative photosensitive resin 7 lands on the transparent substrate 8 tends to decrease. Further, if the discharge speed is increased, the negative photosensitive resin 7 bounces when the negative photosensitive resin 7 lands on the transparent substrate 8, and the negative photosensitive resin 7 scatters outside a desired region.

  As described above, if the driving frequency, the distance from the nozzle of the ink jet head to the transparent substrate 8 and the resin discharge speed are generally set to the above-described conditions, the resin discharge can be suitably performed. The invention is not limited and may be set in consideration of desired conditions as appropriate.

  As the transparent substrate 8, a glass substrate is used. Note that the substrate is not limited to a glass substrate as long as it has transparency, mechanical strength, heat resistance, and the like that can withstand use as a transparent substrate, and a plastic substrate or the like can be used. .

  Moreover, the light-shielding part 20 can use what does not permeate | transmit light, ie, shields light, and has mechanical strength and heat resistance. In the present embodiment, as described above, the light shielding portion 20 is a generic term for the gate wiring 3, the source wiring 4, and the capacitor wiring 5 in the TFT substrate 23.

  Further, the negative photosensitive resin 7 contains a resin having ultraviolet curing properties. In the present embodiment, in the negative photosensitive resin 7, it is necessary that the reaction proceeds selectively only in the region irradiated with ultraviolet rays, and a radical polymerization type ultraviolet curable resin may be selected.

  As the radical polymerization type ultraviolet curable resin, for example, a resin having a photopolymerization oligomer such as urethane acrylate, epoxy acrylate, or ester acrylate as a main component and a photopolymerization initiator added thereto can be used.

  Further, the negative photosensitive resin 7 is desirably left in a small amount on the surface of the glass substrate 8 in a thin film, and it is desirable to use a resin diluted with a large amount of solvent.

  Here, the solvent for diluting the resin is not particularly limited. However, in the ink jet method, if the solvent evaporates on the nozzle surface of the ink jet head, non-ejection may be caused. In addition, there is a problem that the composition of the solvent and the ultraviolet curable resin varies. Therefore, in order to prevent evaporation of the solvent in the resin, it is desirable to select an organic solvent having a low vapor pressure at the temperature (for example, room temperature) at which the inkjet head operates. For example, it is desirable to use carbitol, butyl carbitol, methyl carbitol, carbitol acetate, butyl carbitol acetate, or the like. Or you may mix the diethylene glycol with comparatively high viscosity so that it may be settled in the viscosity range of resin which can be normally discharged by the inkjet method.

  In addition, the viscosity of the negative photosensitive resin 7 should be adjusted to, for example, about 2 to 50 cP, desirably about 5 to 30 cP. If the viscosity is high, the negative photosensitive resin 7 cannot be discharged from the inkjet head. On the other hand, if the viscosity of the negative photosensitive resin 7 is low, the negative photosensitive resin 7 scatters when discharged, a plurality of fine droplets are ejected, and the resin 7 lands other than the desired position. It becomes difficult to discharge the negative photosensitive resin 7 to a desired position.

  The negative photosensitive resin 7 is used for fixing beads 12 (acting as spacers which are three-dimensional structures) to be dispersed in the transparent substrate 8 in a “dispersing step” described later. That is, if the thickness of the beads 12 is constant, the thickness of the negative photosensitive resin 7 affects the height (thickness) of the spacer to be formed. Therefore, when a large amount of the negative photosensitive resin 7 is applied to the light shielding portion 20, the thickness of the resin film itself increases and the height (thickness) of the spacer increases. In addition, the amount of resin to be used increases, and it becomes easier to protrude from the light shielding portion 20 and waste is increased. Therefore, the thickness of the negative photosensitive resin 7 is preferably thin, and is preferably about 0.1 μm or less, for example. Further, the beads 12 are sufficiently fixed to the light-shielding portion 20 via the negative photosensitive resin 7 with a thickness of about 0.1 μm or less. The step of fixing the beads 12 to the light shielding unit 20 will be described in detail later.

  In order to leave a small amount of the negative photosensitive resin 7 on the transparent substrate 8, a resin diluted in a large amount of solvent (for example, a dilution ratio of 90% or more) is adopted as the negative photosensitive resin 7. The discharged resin may be dried to evaporate the solvent. Thereby, the negative photosensitive resin 7 can be thinly left on the substrate.

  Then, by setting the above conditions, a small amount of the negative photosensitive resin 7 is discharged, and the diluted solvent is dried, so that the negative photosensitive resin is formed on the light shielding portion 20 as shown in FIG. Resin 7 is left in a thin film. That is, the negative photosensitive resin 7 can be applied on the transparent substrate 8.

  Here, a state in which the negative photosensitive resin 7 applied to the light-transmitting regions 9 on both sides in the width (W) direction of the light-shielding portion 20 protrudes and is applied is shown. However, the portion where the negative photosensitive resin 7 protrudes does not have to be on both sides of the light shielding portion 20 and may be on one side. The present invention is preferably used when the negative photosensitive resin 7 applied to the light transmitting region 9 protrudes.

  In the following description, the surface of the transparent substrate 8 on which the negative photosensitive resin 7 is applied is referred to as an upper surface (or front surface), and the surface facing away from the upper surface is referred to as a lower surface (or back surface). Further, the surface side of the transparent substrate 8 on which the negative photosensitive resin 7 is applied is referred to as the upper side (or front side), and the surface side facing away from the upper surface is referred to as the lower side (or back side).

(First curing process)
Next, as shown in FIG. 1B, ultraviolet rays 10 are irradiated from the back surface of the transparent substrate 8 coated with the negative photosensitive resin 7. Specifically, as illustrated in FIG. 2, when the ultraviolet light 10 is irradiated from the back surface of the transparent substrate 8, the ultraviolet light 10 is shielded by the light shielding unit 20 in the light shielding region 6, and the ultraviolet light 10 is transmitted only through the light transmitting region 9. Accordingly, only the negative photosensitive resin 7 protruding from the light shielding portion 20 is selectively cured to become the cured resin 11.

  In FIG. 3, the ultraviolet rays 10 are shown to be incident on the transparent substrate 8 surface as parallel light perpendicularly, but even if they have light components oblique to the transparent substrate 8 surface, they are extremely oblique components. As long as there is not much light, it does not matter. That is, even if the end portion of the negative photosensitive resin 7 applied on the light-shielding portion 20 is cured by ultraviolet rays that are inclined from the vertical direction and proceed in an oblique direction with respect to the transparent substrate 8, the beads described later sufficiently 12 can be attached. For example, when the width (W) of the light shielding part 20 is about 20 μm, the end of the negative photosensitive resin 7 on the light shielding part 20 may be cured by about 5 μm or less.

  Further, it is preferable to determine the configuration of the ultraviolet irradiation system in consideration that the ultraviolet rays 10 transmitted through the transparent substrate 8 do not enter the transparent substrate 8 again due to reflection. An ultraviolet irradiation system suitable for this embodiment will be described separately.

  In addition, as for the wavelength of the ultraviolet-ray 10, when the transparent substrate 8 is glass, it is desirable that it is about 300 nm-about 400 nm. More preferably, it is 350 nm-400 nm. For example, the ultraviolet ray 10 of about 300 nm or less has low transmittance with respect to the transparent substrate 8 made of glass or the like, and it becomes difficult to sufficiently irradiate the negative photosensitive resin 7 on the transparent substrate 8 with the ultraviolet ray 10. Further, at a long wavelength (visible light) of about 400 nm or more, the curing processing speed of the negative photosensitive resin 7 becomes slow. In addition, when the material of the transparent substrate 8 is not glass but another material, the wavelength characteristic of the transparent substrate 8 is different from that of the glass, so that the wavelength of the ultraviolet ray 10 may be appropriately determined.

(Spraying process)
As shown in FIG. 1C, after the first curing step is completed, beads 12 are spread on the upper surface of the transparent substrate 8. That is, the beads 12 are dispersed without distinguishing between the light shielding region 6 and the light transmitting region 9. Thereby, the beads 12 are randomly arranged on the surface of the transparent substrate 8.

  The beads 12 may be sprayed by a commonly used spraying method, for example, a dry spraying device spraying using nitrogen or air may be used.

  Further, the beads 12 are used as spacers in the present embodiment. As the beads 12, spherical or cylindrical silica, alumina, synthetic resin, or the like can be used.

  Further, the size of the beads 12 is not particularly limited, but is directly related to the thickness of the liquid crystal layer used in the liquid crystal display element, and therefore, the size (diameter) of the beads 12 is determined according to the desired thickness of the liquid crystal layer. Is desirable. Therefore, for example, spherical beads having a diameter of 3.5 μm can be used.

  The bead 12 is a transparent bead that can transmit the ultraviolet ray 10 in order to irradiate the negative photosensitive resin 7 directly under the bead 12 existing in the light shielding region 6 with the ultraviolet ray 10 in the next “second curing step”. It is desirable that Alternatively, as will be described later, white beads may be used so that the irradiated ultraviolet ray 10 repeats irregular reflection and reaches directly under the beads 12.

(Second curing step)
As shown in FIG. 1 (d), after the step of spraying the beads 12, the uncured negative photosensitive resin present in the light shielding region 6 is irradiated with ultraviolet rays 10 from the upper side of the transparent substrate 8 on which the beads 12 are sprayed. 7 is cured.

  At this time, if the beads 12 are transparent, the ultraviolet rays 10 can pass through the beads 12 and the negative photosensitive resin 7 directly under the beads 12 can be cured. Even if the beads 12 are white, if the light shielding portion 20 is made of a highly reflective material such as metal wiring, and there is an ultraviolet component incident obliquely on the surface of the transparent substrate 8, the metal wiring The negative photosensitive resin 7 directly under the beads 12 can be cured by reflection or irregular reflection on the beads 12.

  However, in this case, since the amount of the ultraviolet ray 10 is reduced just below the bead 12 because it becomes a shadow of the bead 12, sufficient irradiation intensity and irradiation time are set so that the negative photosensitive resin 7 is cured as desired. Must be set.

  Then, the uncured negative photosensitive resin 7 on the light shielding region 6 is cured by the irradiation of the ultraviolet rays 10, and the beads 12 disposed thereon can be fixed to the transparent substrate 8.

  On the other hand, since the negative photosensitive resin 7 existing in the light transmitting region 9 has already been cured by the “first irradiation step”, the beads 12 dispersed in the light transmitting region 9 of the transparent substrate 8 are transparent. It is not fixed in the light transmitting region 9 of the substrate 8.

(Removal process)
As shown in FIG. 1 (e), by removing the beads 12 dispersed in the light transmitting region 9 and not fixed to the transparent substrate 8 in the “second curing step”, a desired transparent Beads 12 that are selectively disposed only on the light shielding region 6 of the substrate 8, that is, the light shielding portion 20, that is, spacers can be formed.

  The method of removing the beads 12 that have not adhered is not particularly limited, but the beads 12 may be sucked by bringing a gas suction port or the like close thereto, or the transparent substrate 8 may be tilted or turned over and removed. . For example, in the case of a transparent substrate for a liquid crystal display element formed by bonding two transparent substrates, the bead 12 removal step may be performed at the timing of tilting the transparent substrate for bonding.

  Through the steps described above, it is possible to selectively form the beads 12 that are three-dimensional structures on the light-shielding portion 20 formed on the transparent substrate 8.

  That is, the beads 12 can be formed on the gate wiring 3, the source wiring 4, and the capacitor wiring 5, which are the light shielding portions 20 of the TFT substrate 23, using the above process. That is, it is possible to selectively form beads 12, that is, spacers that are three-dimensional structures, in the light shielding region 6. Note that. Since the capacitor wiring 5 is arranged so as to cross the pixel electrode 2 which is a translucent region, it is desirable not to apply the negative photosensitive resin 7. Thereby, it can prevent that the bead 12 which is a spacer is formed, and the display nonuniformity resulting from a spacer can be prevented.

  Further, according to the above configuration, even if the negative photosensitive resin 7 protrudes outside the light shielding region 6, that is, up to the light transmitting region 9, the beads 12 are not fixed to the protruding negative photosensitive resin 7 portion. Further, light leakage of the liquid crystal display element due to the beads 12 can be prevented. Therefore, since display unevenness due to the beads 12 can be prevented, a liquid crystal display element with good display quality can be provided.

  Moreover, according to said structure, since the negative photosensitive resin 7 can selectively be hardened | cured by the light-shielding area | region 6 and the translucent area | region 9, the precision of the inkjet head to be used is low, and the application position of the resin to a board | substrate is low. It is easy to deal with any deviation. Therefore, a special inkjet head is not necessary, and a general-purpose inkjet head can be used.

  In addition, since a small amount of resin can be discharged by the inkjet method, the negative photosensitive resin 7 can be discharged to a desired position in the light shielding region 6. That is, the spacer can be formed at a desired position in the light shielding region 6. Therefore, the spacers can be evenly arranged in the light shielding region 6.

  In the above description, the case where the positive photosensitive resin 7 is applied on the light shielding portion 20 formed on the transparent substrate 8 and the beads 12 are fixed to form a three-dimensional structure has been described. It is not limited to. The positive photosensitive resin 7 may be applied to the surface of the transparent substrate 8 opposite to the surface on which the light shielding portion 20 is formed to fix the beads 12. Also in this case, since the light shielding part 20 acts as a mask for shielding the ultraviolet light 10, the beads 12 can be selectively fixed to the light shielding area shielded by the light shielding part 20. Therefore, as long as the light shielding part 20 is formed on the transparent substrate 8, there is a light shielding region, and the beads 12 can be selectively fixed.

  Thereby, for example, even if a protective film or the like used in the liquid crystal display element is formed on the light shielding portion 20 formed on the transparent substrate 8, the beads 12 are selectively selected from above the protective film or the like. It can be fixed to the light shielding region 6. That is, the spacer which is a three-dimensional structure can be selectively formed in the light shielding region 6.

  Further, in the present embodiment, the case where the spacer is formed on the TFT substrate 23 has been described. However, according to the three-dimensional structure forming method of the present embodiment, the substrate (CF) on which the color filter (CF) is formed. It is also possible to form a three-dimensional structure (that is, a spacer) on the substrate. In this case, a three-dimensional structure may be formed in a light shielding region that is shielded by black matrix or the like formed on the CF substrate.

  Next, an ultraviolet irradiation system suitably used in the present embodiment will be described.

  FIG. 4A and FIG. 4B are cross-sectional views showing the main configuration of the ultraviolet irradiation system. As shown in FIG. 4A and FIG. 4B, the ultraviolet irradiation system includes a roller 13 (substrate conveying means) for conveying the transparent substrate 8 and a cylinder for irradiating ultraviolet rays from the lower surface of the transparent substrate 8. -Shaped ultraviolet irradiation lamp (ultraviolet irradiation device) 14, a reflection device 15 for reflecting ultraviolet rays, a black light shielding cover 16 that suppresses reflection of ultraviolet rays, and a first type for efficiently making ultraviolet rays incident on the transparent substrate 8. And two reflection mirrors 21.

  In the ultraviolet irradiation system, a roller 13, an ultraviolet irradiation lamp 14, and a second reflection mirror 21 are disposed on the lower side of the transparent substrate 8, and a reflection device 15 and a light shielding cover 16 are disposed on the upper side. ing.

  Next, each member will be described.

  The rollers 13 are wheels for transporting the transparent substrate 8, and a plurality of the rollers 13 are rotatably provided. The transparent substrate 8 is transported in a predetermined direction by placing the transparent substrate 8 on the rollers 13. be able to. In the figure, the arrow indicates the rotation direction of the roller 13.

  The ultraviolet irradiation lamp 14 irradiates ultraviolet rays from the lower surface of the conveyed transparent substrate 8 and is provided between the rollers 13.

  The reflection device 15 has a reflection surface 15a that reflects light. The reflection device 15 is disposed to face the ultraviolet irradiation lamp 14 with the transparent substrate 8 interposed therebetween. The reflection device 15 is provided so as to be rotated 90 degrees from a parallel state to a vertical state so that the reflection surface 15a faces the transparent substrate 8 by a switching unit (not shown). Further, by rotating the reflecting device 15 by the adjusting means, it is possible to reflect the ultraviolet rays incident on the reflecting surface 15a and irradiate the reflected ultraviolet rays in a predetermined direction.

  Further, the light shielding cover 16 is colored black so that the ultraviolet light is irradiated from the ultraviolet irradiation lamp 14 and reaches the light shielding cover 16, so that the reflection of the ultraviolet light is suppressed. And the light shielding cover 16 is provided so that the circumference | surroundings of the reflection apparatus 15 may be surrounded, and it can prevent that an ultraviolet-ray is irregularly reflected. Therefore, the irregularly reflected ultraviolet rays can be prevented from entering a position different from the desired position on the transparent substrate 8.

  Further, the second reflection mirror 21 is for efficiently making ultraviolet rays incident on the transparent substrate 8 and is provided so as to surround the ultraviolet irradiation lamp 14.

  FIG. 4A is a cross-sectional view in which the reflecting surface 15 a is set to be substantially perpendicular to the transparent substrate 8. As shown in FIG. 4A, since the reflecting surface 15a is perpendicular to the transparent substrate 8, the ultraviolet light applied to the transparent substrate 8 from the ultraviolet irradiation lamp 14 passes through the transparent substrate 8, and then the reflecting surface 15a. The light reaches the light shielding cover 16 without reaching 15a. Alternatively, even if the ultraviolet rays reach the reflecting surface 15a and are reflected, they do not enter the transparent substrate 8 and enter the light shielding cover 16. That is, the ultraviolet light that has passed through the transparent substrate 8 enters the light shielding cover 16. In the light shielding cover 16, the ultraviolet rays are not further reflected, so that the ultraviolet rays that have passed through the transparent substrate 8 can be prevented from entering the surface of the transparent substrate 8 again.

  Therefore, according to the above configuration, in the above-described “first curing step”, it is possible to effectively perform the step of selectively curing the negative photosensitive resin 7 applied to the light transmitting region 9. .

  Next, FIG. 4B is a cross-sectional view in which the reflecting surface 15a is set so as to be substantially parallel to the surface of the transparent substrate 8 to be processed (surface irradiated with ultraviolet rays). As shown in FIG. 4B, when the reflecting surface 15a is inclined substantially parallel or at a slight angle so as to face the surface of the transparent substrate 8 irradiated with ultraviolet rays, the transparent substrate 8 is transmitted from the ultraviolet irradiation lamp 14. Then, the ultraviolet rays emitted above the transparent substrate 8 can be reflected by the reflecting surface 15 a and can be incident again on the transparent substrate 8.

  At this time, the ultraviolet rays transmitted from the ultraviolet irradiation lamp 14 through the transparent substrate 8 and emitted above the transparent substrate 8 also have light components inclined with respect to the surface of the transparent substrate 8 irradiated with the ultraviolet rays. . Therefore, even if the reflective surface 15a is arranged in parallel so as to face the transparent substrate 8, when the ultraviolet light is reflected by the reflective surface 15a, the incident direction and the reflective direction of the ultraviolet light incident on the reflective surface 15a are Will be different. Therefore, the ultraviolet light transmitted through the transparent substrate 8 can be incident again on a desired position (for example, a light shielding region) of the transparent substrate 8. Further, the reflection surface 15 a of the reflection device 15 may be intentionally inclined at a minute angle with respect to the transparent substrate 8. Further, the ultraviolet irradiation process may be performed while changing the tilt angle of the reflecting surface 15a of the reflecting device 15 from the parallel state to the transparent substrate 8 to the tilted state at a minute angle. Thereby, it becomes possible to condense ultraviolet rays with respect to the negative photosensitive resin on the light shielding portion, and it is possible to cure the negative photosensitive resin.

  Therefore, according to the above configuration, it is possible to effectively perform the step of selectively curing the negative photosensitive resin 7 applied to the light shielding region 6 in the “second curing step” described above.

  In addition, with the above-described configuration, in the present ultraviolet irradiation system, it is possible to switch between irradiation from the back surface of the substrate and irradiation from the front surface, and depending on the shape of the cylindrical ultraviolet irradiation lamp 14, It is possible to perform an ultraviolet irradiation process on the light transmitting region 9 and the light shielding region 6.

  Then, by moving the transparent substrate 8 using the rollers 13 (conveying means), the entire surface of the transparent substrate 8 can be irradiated with ultraviolet rays.

  Although the case where the reflection device 15 has a function of rotating is shown in the ultraviolet irradiation system, the reflection device 15 may be any device that can change the state of reflection with respect to ultraviolet rays using the ultraviolet irradiation lamp 14 as a light source.

  For example, a function of moving the reflecting device 15 in which the reflecting surface 15a is formed in parallel to the surface of the transparent substrate 8 irradiated with ultraviolet rays to a position where the ultraviolet rays from the ultraviolet irradiation lamp 14 do not reach is substantially added. It is good also as a structure which does not reflect the ultraviolet-ray radiate | emitted from the downward direction. In other words, it is only necessary that the reflecting device 15 can be moved between a position where ultraviolet rays are irradiated and a position where ultraviolet rays are not irradiated. That is, the transparent substrate 8 and the reflection device 15 may be relatively moved so that the ultraviolet light reflected from the reflection device 15 is not irradiated on the transparent substrate 8.

  Alternatively, a black shutter (switching means) having an opening / closing function is added to the reflecting surface 15a of the reflecting device 15 in which the reflecting surface 15a is formed in parallel to the surface of the transparent substrate 8 irradiated with ultraviolet rays, and the shutter is opened / closed. It is good also as a structure which can be switched to the state which irradiates an ultraviolet-ray, and the state which does not irradiate an ultraviolet-ray by.

  4 (a) and 4 (b) describe the mode in which the glass substrate alone, which is the transparent substrate 8, is conveyed by the roller 13, the substrate holder formed of a transparent material that transmits ultraviolet rays. Alternatively, the transparent substrate 8 may be placed and transported.

  Further, according to the configuration of the present embodiment, it is possible to irradiate ultraviolet rays from both surfaces of the transparent substrate 8 while arranging the ultraviolet irradiation lamp only on one side of the substrate surface.

  Moreover, according to said structure, since it can switch to the state which reflects the ultraviolet rays from the ultraviolet irradiation lamp 14, and the state which does not reflect, such as having the function to rotate the reflecting device 15, only when it is desired, Ultraviolet rays can be irradiated from both sides of the transparent substrate 8.

[Embodiment 2]
Hereinafter, another embodiment of the present invention will be described with reference to the drawings. However, the description overlapping with the first embodiment is omitted.

  FIG. 5A to FIG. 5E are process diagrams of a method for forming a three-dimensional structure according to another embodiment of the present invention. In the figure, among the reference numerals attached to each member, 17 indicates a positive photosensitive resin, and 18 indicates a solubilized resin. In addition, the same number is attached | subjected to the member which shows the effect similar to Embodiment 1, and the description is abbreviate | omitted.

  The method for forming a three-dimensional structure according to this embodiment includes a coating process, a solubilization process, a removal process, and a baking process.

(Coating process)
As shown in FIG. 5A, a positive photosensitive resin 17 containing a resin that is solubilized by ultraviolet rays is discharged onto the light shielding part 20 by an inkjet method on the light shielding part 20 formed on the transparent substrate 8. Then, the discharged positive photosensitive resin 17 exists as droplets on the light shielding unit 20. At this time, a droplet shape is formed so that the surface energy of the droplets of the positive photosensitive resin 17 is minimized. Then, by evaporating the solvent contained in the positive photosensitive resin 17, the positive photosensitive resin 17 is fixed on the light shielding portion 20 in the light shielding region 6. The positive photosensitive resin 17 may protrude from the light shielding portion 20.

  Further, the discharging method of the positive photosensitive resin 17 is the same as that in the first embodiment, and the description thereof is omitted.

  As the positive photosensitive resin 17, a resin containing a positive photoresist is used. The type of the positive photoresist is not particularly limited, and may be appropriately selected from positive resists using a commonly used novolak resin as a base resin. When a small amount of the positive photosensitive resin 17 is discharged by the ink jet method, an organic solvent may be mixed and adjusted to a predetermined viscosity according to the nozzle diameter of the ink jet.

  The type of the solvent is the same as that in the first embodiment. However, in this embodiment, the positive photosensitive resin 17 is a spacer that is a three-dimensional structure, and therefore the dilution rate of the positive photosensitive resin 17 with the solvent. Is preferably set relatively low. For example, the dilution ratio may be about 20 to 80%, and may be determined in consideration of the desired volume for the spacer that remains and becomes a three-dimensional structure, and the ejection volume of the inkjet.

  In order to evaporate the solvent, a normal heat treatment may be performed. For example, if a normal positive type photoresist is used, it is common to carry out heating for about 10 minutes or more at a temperature of about 80 to 100 ° C. The resin components and solvents of the positive type photosensitive resin 17 are used. What is necessary is just to set suitably according to an evaporation state.

(Solubilization process)
Next, as shown in FIG. 5B, ultraviolet rays 10 are irradiated from the back surface of the transparent substrate 8 coated with the positive photosensitive resin 17. At this time, since the ultraviolet rays 10 are shielded in the light shielding region 6 (the light shielding portion 20), only the positive photosensitive resin 17 protruding into the light transmitting region 9 is selectively exposed. Thereby, the positive photosensitive resin 17 becomes soluble in the medicine. Here, the positive photosensitive resin 17 that has become soluble is referred to as a solubilized resin 18.

  Since the ultraviolet ray 10 includes only parallel light and light of an oblique component, the ultraviolet ray 10 circulates and the vicinity of the end portion of the positive photosensitive resin 17 on the light shielding portion 20 can be exposed. It is sufficient that the exposure range does not reach the portion where the height of the conductive resin 17 from the transparent substrate is the highest.

(Removal process)
As shown in FIG. 5 (c), after the above-described solubilization step is completed, a chemical treatment is performed with a developer corresponding to a positive resist which is a resin component of the positive photosensitive resin 17, and development is performed. That is, the solubilized resin 18 is removed from the light transmitting region 9.

  In general, a strong alkaline chemical solution is used as a positive resist developer, and a chemical solution for positive resist development is appropriately selected in conjunction with the positive resist which is a resin component of the positive photosensitive resin 17. Thereby, the positive photosensitive resin 17 can remain only on the light shielding portion 20. That is, the positive photosensitive resin 17 can remain in the light shielding region 6.

(Baking process)
As shown in FIG. 5D, in order to improve the adhesion between the positive photosensitive resin 17 and the transparent substrate 8, the positive photosensitive resin 17 is further heat-treated and baked. The fired positive photosensitive resin 17 becomes a fired positive photosensitive resin 22. In addition, the temperature for baking is good to set about 20 degreeC or more higher than the temperature set in order to evaporate the solvent of the said application | coating process.

  Through the above steps, a spacer that is a three-dimensional structure can be selectively formed in the light shielding region 6 of the transparent substrate 8 as shown in FIG.

  In the baking process, the shrinkage amount of the positive photosensitive resin 17 can be adjusted by changing the heating temperature and the heating time. Therefore, the height of the spacer to be aligned to a desired height can be controlled by the heating temperature and the heating time. For example, in the step of forming the positive photosensitive resin 17 only in the light shielding region 6, that is, in the state of FIG. 5C, the height of the positive photosensitive resin 17 is measured, and a desired shrinkage amount is estimated, If firing is performed under the corresponding firing conditions, it is easy to control the height of the spacer to a desired height. Furthermore, after that, when the height of the formed spacer is higher than the desired height, it can be adjusted to the desired height by additional firing. That is, it is possible to provide a method for forming a spacer with high height accuracy that can monitor the height and feed back the result.

  In addition, this method facilitates the manufacture of liquid crystal display elements having different spacer height specifications when manufacturing the liquid crystal display elements. That is, when the height of the spacer is changed, the height of the spacer can be adjusted depending on the firing conditions, so the amount of discharge of the positive photosensitive resin 17 and the type of resin component contained in the positive photosensitive resin 17 can be changed. It is not always necessary to change and adjust the height of the spacer. Accordingly, it is not necessary to frequently change the setting of conditions such as resin discharge in accordance with each type in the process of manufacturing a small quantity and a wide variety of liquid crystal display elements, so that a simple spacer forming method can be provided.

  When the positive photosensitive resin 17 is sufficiently fixed to the transparent substrate 8 and when it is not necessary to adjust the height, the above baking step can be omitted.

  In the present embodiment, the positive photosensitive resin 17 is arranged so that the central portion of the positive photosensitive resin 17 is disposed in the light shielding region 6 when the positive photosensitive resin 17 is discharged in the coating process. Is preferably discharged. Thus, even if a part of the positive photosensitive resin 17 is removed in the removing step, the height of the positive photosensitive resin 17 that has not been removed does not change. Therefore, as long as the discharge amount is constant, it is possible to form a spacer made of the positive photosensitive resin 17 having a uniform height in the light shielding region 6.

  Further, according to the present embodiment, when the liquid crystal display element is formed by the transparent substrate on which the three-dimensional structure is formed and the other substrate, the portion in contact with the other substrate in the three-dimensional structure is another substrate. It becomes a substantially plane parallel to. Therefore, even when another substrate is placed and pressed against the three-dimensional structure during the manufacture of the liquid crystal display element, the load is applied to the three-dimensional structure only in the pressed direction. That is, a load acting in another direction (for example, a direction parallel to the substrate) is not received. Therefore, it is possible to prevent the three-dimensional structure from being deformed in the other direction. That is, the cell gap can be kept uniform.

  Further, according to the present embodiment, the spacers are formed by the number of positive photosensitive resins ejected by the ink jet method. That is, since the number of spacers to be formed can be arbitrarily controlled, a fixed number of spacers can be formed for each picture element of the liquid crystal display element, and the spacers can be evenly arranged in the light shielding region of the liquid crystal display element.

  In addition, according to the present embodiment, the wettability between the positive photosensitive resin 17 and the transparent substrate 8 is changed by changing the surface state of the transparent substrate 8 or using a resin having a different surface energy. Can be made. Thereby, the area (bottom area) of the surface in contact with the transparent substrate 8 in the three-dimensional structure can be changed without changing the height of the three-dimensional structure formed on the transparent substrate 8. Alternatively, the height of the three-dimensional structure can be changed without changing the bottom area of the three-dimensional structure. Therefore, the elastic modulus of the three-dimensional structure can be changed. Further, the elastic modulus of the entire three-dimensional structure can be changed by changing the density of the three-dimensional structure to be produced without changing the size of the three-dimensional structure. Therefore, the elastic modulus of the three-dimensional structure can be controlled in response to external stress applied to the three-dimensional structure.

  In the three-dimensional structure, the region occupied by the three-dimensional structure gradually increases from the highest part of the three-dimensional structure toward the transparent substrate 8. Therefore, the elastic modulus of the three-dimensional structure, that is, the amount of deformation with respect to stress changes. Therefore, it is possible to change the external stress according to the change of the deformation amount. Further, when the formed three-dimensional structure is approximated as a part of a sphere, the elastic modulus of the three-dimensional structure can be controlled by the size of the approximated sphere.

  Further, since there is no need to apply a positive photosensitive resin to the entire surface of the substrate unlike the conventional spacer forming method using photolithography, a spacer which is a three-dimensional structure can be formed with a small amount of the positive photosensitive resin 17. , Material cost can be reduced.

  The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope shown in the claims, and embodiments obtained by appropriately combining technical means disclosed in different embodiments. Is also included in the technical scope of the present invention.

  According to the present invention, since a three-dimensional structure can be selectively formed in the light shielding region of the transparent substrate, it can be suitably applied when forming a spacer of a liquid crystal display element.

It is process drawing of the formation method of the three-dimensional structure which concerns on one Embodiment of this invention. It is sectional drawing explaining the formation method of the three-dimensional structure which concerns on one Embodiment of this invention. It is a top view which shows schematic structure for one picture element of the transparent substrate which comprises the liquid crystal display element concerning one Embodiment of this invention. It is sectional drawing which shows schematic structure of the ultraviolet irradiation system which concerns on one Embodiment of this invention, (a) shows the state in which the reflective surface of a reflection apparatus is substantially perpendicular | vertical with respect to a transparent substrate, (b) is a reflection apparatus. The reflecting surface is substantially parallel to the transparent substrate. It is process drawing of the formation method of the three-dimensional structure which concerns on other embodiment of this invention.

Explanation of symbols

1 Drain electrode 2 Pixel electrode 3 Gate wiring (metal wiring)
4 Source wiring (metal wiring)
5 Capacitor wiring (metal wiring)
6 Light-shielding area 7 Negative photosensitive resin 8 Transparent substrate 9 Translucent area 10 Ultraviolet light 11 Cured resin 12 Beads (three-dimensional structure)
13 Roller (conveying means)
14 UV irradiation lamp (UV irradiation device)
DESCRIPTION OF SYMBOLS 15 Reflector 15a Reflecting surface 16 Light-shielding cover 17 Positive photosensitive resin 18 Solubilization resin 19 Thin transistor (TFT)
20 Shading part 21 Reflecting mirror 22 Firing positive photosensitive resin (three-dimensional structure)
23 TFT substrate W Shield width

Claims (12)

A method of forming a three-dimensional structure on a light-shielding portion formed on a transparent substrate,
An application step of applying a negative photosensitive resin to the transparent substrate;
The negative photosensitive resin applied to the area not shielded by the light-shielding portion by irradiating ultraviolet rays through the transparent substrate from the side facing away from the surface coated with the negative photosensitive resin in the transparent substrate. A first curing step for curing the resin;
A spreading step of spreading beads on the surface of the transparent substrate coated with the negative photosensitive resin,
In the transparent substrate, ultraviolet light is applied from the side coated with the negative photosensitive resin to cure the negative photosensitive resin in the region not cured in the first curing step, and the beads are transparent substrate A second curing step to fix to
And a removing step of removing the beads not fixed to the transparent substrate in the second curing step from the transparent substrate. A method of forming a three-dimensional structure on a light-shielding portion formed on a transparent substrate,
An application step of applying a positive photosensitive resin to the transparent substrate;
A positive photosensitive resin formed in a region that is not shielded by a light shielding portion by irradiating ultraviolet rays through the transparent substrate from the side facing away from the surface coated with the positive photosensitive resin in the transparent substrate. A solubilization step for solubilizing
A removal step of removing the positive photosensitive resin solubilized in the solubilization step with a solvent;
And a step of baking the positive photosensitive resin that has not been removed in the removing step.   3. The method for forming a three-dimensional structure according to claim 1, wherein the coating step uses an ink jet method.   The said application | coating process includes discharging the said positive photosensitive resin so that it may arrange | position in the area | region where the center part of positive photosensitive resin is light-shielded by the light-shielding part using the inkjet method. A method of forming the three-dimensional structure described. A method of forming a spacer for a liquid crystal display element,
A spacer, which is a three-dimensional structure for controlling the thickness of the liquid crystal layer, is formed on the transparent substrate on which the light shielding portion is formed, using the forming method according to claim 1. A method for forming a spacer for a liquid crystal display element.   6. The method for forming a spacer for a liquid crystal display element according to claim 5, wherein the light shielding portion is a metal wiring of a liquid crystal driving element. A light-shielding portion and a three-dimensional structure;
A transparent photosensitive resin characterized in that a negative photosensitive resin is applied to the light shielding area shielded by the light shielding portion, and a three-dimensional structure is formed only in the light shielding area through the negative photosensitive resin. substrate. A light-shielding portion and a three-dimensional structure made of a positive photosensitive resin;
The said three-dimensional structure is formed by arrange | positioning the center part of positive type photosensitive resin in the light-shielding area light-shielded by the said light-shielding part, The transparent substrate characterized by the above-mentioned. An ultraviolet irradiation device for irradiating the substrate to be processed with ultraviolet rays;
A reflection device that reflects the ultraviolet rays and irradiates the substrate to be processed;
A transport means for transporting the substrate to be processed between the ultraviolet irradiation device and the reflection device;
An ultraviolet irradiation system characterized by further comprising switching means for switching the reflection device between a state in which the substrate to be processed is irradiated with ultraviolet rays and a state in which the substrate to be processed is not irradiated with ultraviolet rays.   The ultraviolet irradiation system according to claim 9, wherein the switching unit is configured to switch between the two states by rotating the reflecting device.   The ultraviolet irradiation system according to claim 9, wherein the switching unit includes a light shielding member that shields the reflection device.   The ultraviolet irradiation system according to claim 9, wherein the switching unit moves the reflection device to a position where ultraviolet light is irradiated and a position where ultraviolet light is not irradiated.

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