JP4612773B2 - Optical element manufacturing method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an optical element such as a color filter, which is a constituent member of a color liquid crystal element used in a color television, a personal computer, or a pachinko game machine, and an electroluminescent element for full color display having a plurality of light emitting layers. More particularly, the present invention relates to an optical element manufactured by the manufacturing method and a liquid crystal element using a color filter which is one of the optical elements.
[0002]
[Prior art]
In recent years, with the development of personal computers, especially portable personal computers, the demand for liquid crystal displays, particularly color liquid crystal displays, has been increasing. However, cost reduction is necessary for further dissemination, and there is an increasing demand for cost reduction of color filters that are particularly heavy in terms of cost.
[0003]
Conventionally, various methods have been tried to meet the above-described requirements while satisfying the required characteristics of the color filter, but a method that satisfies all the required characteristics has not yet been established. Each method will be described below.
[0004]
The first method is a staining method. In the dyeing method, first, a water-soluble polymer material layer, which is a dyeing material, is formed on a transparent substrate, patterned into a desired shape by a photolithography process, and then the obtained pattern is immersed in a dyeing bath. To obtain a colored pattern. By repeating this step three times, a colored layer composed of three colored portions of R (red), G (green), and B (blue) is formed.
[0005]
The second method is a pigment dispersion method, which has been most actively performed in recent years. In this method, first, a photosensitive resin layer in which a pigment is dispersed is formed on a transparent substrate, and this is patterned to obtain a monochromatic pattern. By repeating this process three times, a colored layer composed of colored portions of R, G, and B is formed.
[0006]
There is an electrodeposition method as a third method. In this method, first, a transparent electrode is patterned on a transparent substrate, and immersed in an electrodeposition coating solution containing a pigment, a resin, an electrolytic solution, etc., and the first color is electrodeposited. This process is repeated three times to form a colored layer composed of three colored portions of R, G, and B, and finally fired.
[0007]
As a fourth method, a pigment is dispersed in a thermosetting resin, and printing is repeated three times to separate R, G, and B, and then the resin is thermally cured to form a colored layer. Is. In any method, a protective layer is generally formed on the colored layer.
[0008]
The point common to these methods is that it is necessary to repeat the same process three times in order to color the three colors of R, G, and B, resulting in high costs. Further, there is a problem that the yield decreases as the number of steps increases. Furthermore, in the electrodeposition method, the shape of the pattern that can be formed is limited, so that it is difficult to apply to the structure of a TFT type (active matrix driving method using a TFT, ie, a thin film transistor as a switching element) with the current technology. It is.
[0009]
Also, since the printing method has poor resolution, it is not suitable for forming a fine pitch pattern.
[0010]
In order to compensate for the above drawbacks, in recent years, a method for producing a color filter using an inkjet method has been actively studied. The method using the ink jet method has an advantage that the manufacturing process is simple and the cost is low.
[0011]
On the other hand, the inkjet method is not limited to the manufacture of color filters, but can also be applied to the manufacture of electroluminescence elements (hereinafter referred to as “EL elements”).
[0012]
The EL element has a structure in which a thin film containing a fluorescent inorganic and organic compound is sandwiched between a cathode and an anode, and excitons are formed by injecting electrons and holes into the thin film and recombining them. It is an element that generates and emits light by using emission of fluorescence or phosphorescence when the exciton is deactivated. A fluorescent material used for such an EL element can be applied to a substrate on which an element such as a TFT is formed by an inkjet method to form a light emitting layer, whereby the element can be configured.
[0013]
[Problems to be solved by the invention]
As described above, since the ink jet system can simplify the manufacturing process and reduce the cost, it is applied to the manufacture of optical elements such as color filters and EL elements. However, in the manufacture of such an optical element, there are problems such as “color mixing” and “white spot” as problems peculiar to the ink jet system. Hereinafter, a case where a color filter is manufactured will be described as an example.
[0014]
“Mixed color” is a failure that occurs when ink is mixed between adjacent pixels (colored portions) of different colors. In the manufacturing method of the color filter in which the black matrix is used as a partition and ink is applied to the opening of the black matrix to form a colored portion, the volume is several to several tens of times the volume of the opening of the black matrix. It is necessary to apply an ink having When the solid content concentration of the colorant or the curing component contained in the ink is high, that is, when the volume of the applied ink is relatively small, the black matrix functions sufficiently as a partition wall, and the inside of the opening of the black matrix Since the ink can be held, the applied ink does not go over the black matrix and reach the colored portions of different colors adjacent to each other. However, when the solid concentration in the ink is low, that is, when it is necessary to apply a large amount of ink, the ink overflows beyond the black matrix serving as the partition wall, and color mixing occurs between adjacent colored portions. Resulting in. In particular, there is a limit to the viscosity of ink that can be stably ejected from the nozzles of an inkjet head, and there is also a limit to the concentration of solids contained in the ink, so a technique for avoiding color mixing is necessary. .
[0015]
In view of this, a method for preventing color mixing by utilizing a difference in wettability of ink between the colored portion and the partition wall has been proposed. For example, Japanese Patent Application Laid-Open No. 59-75205 proposes a method of forming a diffusion prevention pattern with a substance having poor wettability in order to prevent the ink from spreading outside the target area. Not disclosed. On the other hand, JP-A-4-123005 proposes a method of patterning a silicone rubber layer having a large water and oil repellency to form a partition wall for preventing color mixing. Further, JP-A-5-241011 and JP-A-5-241012 similarly disclose a method in which a silicone rubber layer is formed on a black matrix serving as a light shielding layer and used as a partition for preventing color mixing.
[0016]
According to these methods, even when an amount of ink far exceeding the height of the partition is applied, the surface layer of the partition shows ink repellency so that the ink is repelled, and the adjacent colored portion beyond the partition. Therefore, it is possible to effectively prevent color mixing.
[0017]
FIG. 7 shows a conceptual diagram thereof. In the figure, 71 is a transparent substrate, 73 is a black matrix that also serves as a partition, and 76 is ink. When the upper surface of the black matrix 73 has ink repellency, as shown in FIG. 7B, the applied ink 76 is held in the opening of the black matrix 73 and reaches the adjacent colored portion. There is no. However, when the ink repellency of the upper surface of the black matrix 73 is low, as shown in FIG. 7A, the applied ink 76 spreads over the black matrix 73 and is applied to the adjacent openings. It mixes with ink.
[0018]
In general, it is possible to obtain better ink repellency by using a fluorine compound than by using a silicon compound. For example, Japanese Patent Application Laid-Open No. 2000-35511 discloses a method of forming a positive resist pattern on a light-shielding portion, and further applying an ink repellent treatment agent on the pattern. The use of compounds is disclosed. However, in this method, it is necessary to remove the positive resist pattern provided on the light-shielding portion after forming the colored portion. However, when the resist pattern is removed, problems such as dissolution, peeling, and swelling of pixels may occur. is there.
[0019]
As a method for fluorinating the surface of the resin layer, the Chemical Society of Japan, 1985 (10) p. In 1916 to 1923, a method is proposed in which a reaction gas of a fluorine compound is converted into plasma. Further, as an example in which this technique is applied to a color filter, in Japanese Patent Laid-Open No. 11-271753, the partition wall has a multilayer structure of a lower layer having affinity for ink and an upper layer having non-affinity, and the upper layer is used for ink. As a technique for making it non-affinity, a plasma treatment method using a gas containing a fluorine compound is disclosed.
[0020]
However, any of the above-described methods is to multi-layer the partition walls, and it is necessary to carry out the photolithography process a plurality of times. Therefore, there is a problem that the process is complicated, the cost is increased, and the yield is lowered.
[0021]
On the other hand, “blank” is a failure that occurs mainly because the applied ink cannot be sufficiently and uniformly diffused in the area surrounded by the partition walls, such as color unevenness and a decrease in contrast. It causes display failure.
[0022]
FIG. 8 shows a conceptual diagram of white spots. FIG. 8A is a schematic plan view, and FIG. 8B is a schematic cross-sectional view taken along the line AB of FIG. In the figure, the same members as those in FIG. Reference numeral 78 denotes a white portion.
[0023]
In recent years, in color filters for TFT-type liquid crystal elements, the shape of the opening of the black matrix 73 has become complicated for the purpose of protecting the TFT from external light or for obtaining a bright display by increasing the aperture ratio. In addition, since those having a plurality of corner portions are generally used, as shown in FIG. 8A, there is a problem that the ink 76 does not sufficiently diffuse into the corner portions. In forming the black matrix 73, a photolithography process using a liquid resist or a dry resist is generally used, and contaminants adhere to the surface of the transparent substrate 71 due to various components contained in the resist. As a result, the diffusion of the ink 76 may be hindered. Furthermore, when the ink repellency on the side surface of the black matrix 73 is extremely high compared to the surface of the transparent substrate 71, the ink 76 is repelled on the side surface of the black matrix 73 as shown in FIG. There may be a problem that the color becomes light at the portion where the ink 76 and the black matrix 73 are in contact with each other.
[0024]
As a technique for solving such problems of color mixture and white spots, in Japanese Patent Application Laid-Open No. 9-203803, a region (concave portion) surrounded by a black matrix (convex portion) has a contact angle of 20 ° or less with respect to water. It has been proposed to use a substrate that has been subjected to ink-philic treatment so that Examples of methods for imparting ink affinity include water-soluble leveling agents and water-soluble surfactants. Furthermore, in order to simultaneously solve the above-mentioned problem with respect to color mixing, a method for imparting ink repellency by treating the surface of the convex portion with an ink repellent treatment agent in advance is disclosed, and a fluorine-containing silane cup is used as the ink repellent treatment agent. A method of coating with a fluorine-based solvent using a ring agent is exemplified. At this time, as a method for selectively repelling only the surface layer of the convex portion and not repelling the side surface of the convex portion,
(1) Two kinds of materials are laminated so that the convex part itself has such a property.
(2) Cover portions other than the convex portion with a resist, and apply an ink repellency treatment only to the upper surface of the convex portion. (3) Form a resist layer on the transparent substrate, and perform an ink repellency treatment on the entire surface, followed by a photolithography process. The method of patterning a resist layer by, for example, forming a convex part is illustrated.
[0025]
Similarly, Japanese Patent Application Laid-Open No. 9-230129 discloses a method of irradiating energy rays as a method of making a concave portion an ink-philic process. Also in this case, as a method of making the surface layer of the convex portion ink repellent, a photosensitive material for forming the convex portion is applied on a glass substrate, and the entire surface is treated with an ink repellent treatment agent, and then photolithography is performed. A technique for patterning a photosensitive material by a process is illustrated. Thereafter, the convex portion and the concave portion are simultaneously or selectively subjected to ink-inking treatment by irradiation with energy rays.
[0026]
However, all of these methods are such that the surface of the convex portion is subjected to the ink repellent treatment and then the concave portion is subjected to the ink repellent treatment. There is a problem that the ink repellency is lowered. Therefore, it is difficult to obtain sufficient ink affinity on the transparent substrate surface and the side surface of the black matrix, and sufficient ink repellency on the upper surface of the black matrix.
[0027]
The above problem also occurs when an EL element is manufactured by an inkjet method. That is, in an EL element, for example, when an organic semiconductor material that emits light of R, G, and B is used as an ink, and the ink is applied to a region surrounded by a partition wall to form a pixel (light emitting layer), When ink is mixed between adjacent light emitting layers, there is a problem that light emission of a desired color and luminance cannot be obtained in the light emitting layer. Even in the case of a single color light emitting layer, the amount of ink filled in the partition is made uniform, so when ink flows into adjacent pixels, the amount of ink becomes non-uniform, which is recognized as luminance unevenness, which is a problem. It becomes. Further, when the ink is not sufficiently diffused in the region surrounded by the partition walls, there is a problem that sufficient light emission luminance cannot be obtained at the boundary portion between the light emitting layer and the partition walls. In the following description, for the sake of convenience, even in the case of manufacturing an EL element, the mixture of ink between adjacent light emitting layers is “color mixing”, and the luminance unevenness due to the repulsion of ink at the boundary between the light emitting layer and the partition wall. Occurrence of the occurrence is described as “white”.
[0028]
An object of the present invention is to solve the above problems and provide a highly reliable optical element with a high yield when an optical element such as a color filter or an EL element is manufactured at low cost by a simple process using an inkjet method. It is in. Specifically, when ink is applied to an area surrounded by a partition wall, color mixing between adjacent pixels is prevented, and ink is sufficiently diffused in the area to form a pixel with a flat surface. It is to form. A further object of the present invention is to provide a liquid crystal element excellent in color display characteristics at a lower cost by using the optical element obtained by the production method.
[0029]
[Means for Solving the Problems]
  A first aspect of the present invention is a method of manufacturing an optical element having at least a plurality of pixels on a support substrate and a partition wall positioned between adjacent pixels,
  Forming a photosensitive resin composition layer on a support substrate, pattern exposure and development to form a partition pattern, a step of subjecting the partition pattern to light irradiation, and a heat treatment to the partition pattern irradiated with light. A step of forming a partition wall, a step of subjecting the support substrate to an ink-philic treatment, and the partition wallAnd support substrateA step of applying a fluorination treatment to the substrate, a step of performing an ink spreading property improving process for bringing water into contact with the surface of the support substrate, and a step of forming a pixel by applying ink to a region surrounded by the partition wall by an ink jet method. , At leastIn this order,
  The fluorination treatment is a plasma treatment in which plasma irradiation is performed by introducing a gas containing at least fluorine atoms.This is a method for manufacturing an optical element.
[0030]
  The optical element manufacturing method of the present invention includes the following configuration as a preferred embodiment. The partition pattern forming step is a step by photolithography using a liquid resist or a film resist. The light irradiation treatment of the partition pattern irradiates light from both surfaces of the support substrate. The ink-repellent treatment is a dry etching treatment in which a gas containing at least one selected from oxygen, argon, and helium is introduced, and the support substrate is irradiated with plasma in a reduced pressure atmosphere or an atmospheric pressure atmosphere.. UpThe gas introduced in the plasma treatment is CF_Four, SF₆, CHF_Three, C₂F₆, C_ThreeF₈, C_FiveF₈At least one halogen gas selected from₂It is a mixed gas with gas and O₂The mixing ratio is 30% or less. The ink spreading property improving process is a process of irradiating ultrasonic waves while bringing water into contact with the support substrate. The said partition is formed with a black photosensitive resin composition. The ink contains at least a curing component, water, and an organic solvent. A color filter in which the ink contains a colorant and the pixel is a colored portion is manufactured. The electroluminescent element in which the ink contains a light emitting material and the pixel is a light emitting layer is manufactured.
[0034]
DETAILED DESCRIPTION OF THE INVENTION
In the method for producing an optical element of the present invention, a photosensitive resin composition layer is formed on a support substrate, and exposure and development treatment are performed to form a predetermined partition pattern, light irradiation treatment, heat treatment (post-bake treatment). In addition, after performing the ink-repellent treatment, the fluorination treatment, and the ink spreading property improving treatment, ink is applied to the region surrounded by the partition wall to form a pixel. In the manufacturing method of the present invention, at the time of forming the partition wall, by performing a light irradiation process prior to the post-baking process, generation of distortion of the shape due to thermal contraction of the partition wall pattern in the post-baking process is suppressed, and the partition pattern substrate By making the cross-sectional shape in the normal direction closer to a rectangle, the occurrence of white spots can be suppressed. In the present invention, after the ink repellency treatment by the fluorination treatment, the ink spreading property improving treatment in which the supporting substrate is brought into contact with water is performed, so that the ink applied in the subsequent step spreads well on the supporting substrate, and the white Occurrence of omission can be better prevented.
[0035]
In the present invention, the above “ink” is a generic term for, for example, optically and electrically functional liquids after being dried and cured, and is not limited to conventionally used coloring materials.
[0036]
Examples of the optical element of the present invention manufactured by the manufacturing method of the present invention include a color filter and electroluminescence (EL element). First, embodiments of the optical element of the present invention will be described.
[0037]
FIG. 4 schematically shows a cross section of an example of a color filter which is an embodiment of the optical element of the present invention. In the figure, 41 is a transparent substrate as a support substrate, 42 is a black matrix that also serves as a partition, 43 is a colored portion that is a pixel, and 44 is a protective layer that is formed as necessary. When the liquid crystal element is configured using the color filter of the present invention, ITO (indium tin) for driving the liquid crystal is further formed on the colored portion 43 or the protective layer 44 on the colored portion 43. A transparent conductive film made of a transparent conductive material such as oxide) may be formed and provided.
[0038]
FIG. 5 is a schematic cross-sectional view of an embodiment of the liquid crystal element of the present invention, which is configured using the color filter of FIG. In the figure, 47 is a common electrode (transparent conductive film), 48 is an alignment film, 49 is a liquid crystal, 51 is a counter substrate, 52 is a pixel electrode, and 53 is an alignment film. Therefore, the description is omitted.
[0039]
A color liquid crystal element is generally formed by combining a substrate 41 on the color filter side and a counter substrate 51 and enclosing a liquid crystal 49. TFTs (not shown) and pixel electrodes 52 are formed in a matrix inside one substrate 51 of the liquid crystal element. Further, a color filter coloring portion 43 is formed inside the substrate 41 on the color filter side so that R, G, and B are arranged at positions facing the pixel electrode 52, and a transparent common electrode is formed thereon. 47 is formed. Further, alignment films 48 and 53 are formed in the planes of both substrates, and liquid crystal molecules are arranged in a certain direction. These substrates are arranged to face each other via a spacer (not shown), are bonded together by a sealing material (not shown), and the gap is filled with liquid crystal 49.
[0040]
When the liquid crystal element is a transmissive type, the substrate 51 and the pixel electrode 52 are formed of a transparent material, a polarizing plate is bonded to the outside of each substrate, and a backlight generally combining a fluorescent lamp and a scattering plate. Is used to make the liquid crystal compound function as an optical shutter that changes the light transmittance of the backlight. In the case of the reflective type, the substrate 51 or the pixel electrode 52 is formed of a material having a reflection function, or a reflective layer is provided on the substrate 51, and a polarizing plate is provided outside the transparent substrate 41. Display is performed by reflecting light incident from the filter side.
[0041]
FIG. 6 shows a schematic cross-sectional view of an example of an organic EL element which is another embodiment of the optical element of the present invention. In the figure, 61 is a drive substrate, 62 is a partition, 63 is a light emitting layer as a pixel, 64 is a transparent electrode, and 66 is a metal layer. In this figure, only one pixel region is shown for simplification.
[0042]
The driving substrate 61 has TFTs (not shown), wiring films, insulating films and the like laminated in multiple layers, and a voltage can be applied in units of light emitting layers between the transparent electrodes 64 disposed for each of the metal layers 66 and the light emitting layers 63. It is configured. The drive substrate 61 is manufactured by a known thin film process.
[0043]
In the case of constituting an organic EL device in the present invention, the structure includes at least a light emitting material in a partition made of a resin composition between a pair of anodes and cathodes, at least one of which is transparent or translucent. As long as the pixel is formed by filling ink, there is no particular limitation, and a known structure can be adopted, and various modifications can be made without departing from the gist of the present invention. .
[0044]
The laminated structure is, for example,
(1) Electrode (cathode) / light emitting layer / hole injection layer / electrode (anode)
(2) Electrode (anode) / light emitting layer / electron injection layer / electrode (cathode)
(3) Electrode (anode) / hole injection layer / light emitting layer / electron injection layer / electrode (cathode)
(4) Electrode (anode or cathode) / light emitting layer / electrode (cathode or anode)
However, the present invention can also be applied to an EL element having a stacked structure in which an organic compound layer having any one of the above structures is provided.
[0045]
The above (1) and (2) are referred to as a two-layer structure, (3) as a three-layer structure, and (4) as a single-layer structure. The organic EL element in the present invention is based on these laminated structures, but may have a structure in which (1) to (4) other than these are combined or a plurality of layers. Further, a full color display may be realized by combining with a color filter. The shape, size, material, formation process of members other than the partition walls and pixels, and the like of the organic EL element having the laminated structure are appropriately selected according to the use of the organic EL element and are not particularly limited.
[0046]
In the present invention, various materials can be used as the light emitting material used for the light emitting layer of the organic EL element, and examples thereof include fluorescent organic compounds. As the fluorescent organic compound, both a low molecular fluorescent substance and a high molecular fluorescent substance are preferably used, and a polymeric fluorescent substance is more preferable because it can be easily applied to an ink jet system.
[0047]
For example, the low-molecular phosphor is not particularly limited, but naphthalene and derivatives thereof, anthracene and derivatives thereof, perylene and derivatives thereof, polymethine dyes, xanthene dyes, coumarin dyes, cyanine dyes, 8-hydroxyquinoline, and the like. And metal complexes of the derivatives thereof, aromatic amines, tetraphenylcyclopentadiene and derivatives thereof, tetraphenylbutadiene and derivatives thereof, and the like can be used. Specifically, for example, known ones such as those described in JP-A-57-41781 and JP-A-59-184383 can be used.
[0048]
The polymeric fluorescent substance that can be used as the light emitting material is not particularly limited, and examples thereof include polyphenylene vinylene, polyarylene, polyalkylthiophene, and polyalkylfluorene.
[0049]
In the present invention, the polymeric fluorescent substance used in the organic EL device may be a random, block or graft copolymer, or a polymer having an intermediate structure thereof, for example, a random copolymer having a block property. It may be a polymer. From the viewpoint of obtaining a polymer fluorescent substance having a high fluorescence quantum yield, a random copolymer having a block property and a block or graft copolymer are preferable to a complete random copolymer. In addition, since the organic EL element of the present invention utilizes light emission from a thin film, the polymer fluorescent substance having fluorescence in a solid state is used.
[0050]
Examples of the good solvent for the polymeric fluorescent substance include chloroform, methylene chloride, dichloroethane, tetrahydrofuran, toluene, xylene and the like. Although depending on the structure and molecular weight of the polymeric fluorescent substance, it can usually be dissolved in these solvents in an amount of 0.1% by weight or more.
[0051]
In the organic EL device of the present invention, the electron transport material used in the electron transport layer in the case where an electron transport layer is further provided between the light emitting layer and the cathode, or mixed with the hole transport material and the light emitting material is used. And has a function of transmitting electrons injected from the cathode to the light emitting material. There is no restriction | limiting in particular about such an electron transport material, Arbitrary things can be selected and used from a conventionally well-known compound.
[0052]
Preferable examples of the electron transporting material include nitro-substituted fluorenone derivatives, anthraquinodimethane derivatives, diphenylquinone derivatives, thiopyran dioxide derivatives, heterocyclic tetracarboxylic acid anhydrides, and carbodiimides.
[0053]
Further examples include fluorenylidenemethane derivatives, anthraquinodimethane derivatives and anthrone derivatives, oxadiazole derivatives, and the like. Further, although disclosed as a material for forming a light emitting layer, 8-hydroxyquinoline and metal complexes of derivatives thereof can also be used as an electron transporting material.
[0054]
In the EL device of the present invention, the light emitting layer is generally formed in a thin film shape in combination with an appropriate binder resin. The binder resin can be selected from a wide range of resin materials, such as polyvinyl carbazole resin, polycarbonate resin, polyester resin, polyarylate resin, butyral resin, polystyrene resin, polyvinyl acetal resin, diallyl phthalate resin, acrylic resin, methacrylic resin, Examples thereof include, but are not limited to, phenol resins, epoxy resins, silicone resins, polysulfone resins, urea resins, and the like. These may be used alone or in combination as a copolymer polymer.
[0055]
Also, the anode material should have a work function as large as possible. For example, nickel, gold, platinum, palladium, selenium, rhenium, iridium and their alloys, or tin oxide, indium tin oxide (ITO), and copper iodide can be used. preferable. Further, conductive polymers such as poly (3-methylthiophene), polyphenylene sulfide, or polypyrrole can also be used. On the other hand, silver, lead, tin, magnesium, aluminum, calcium, manganese, indium, chromium, or alloys thereof having a small work function are used as the cathode material.
[0056]
The EL element needs to be transparent or translucent on the side of the light emitting layer where light emission is observed. For example, in the configuration of FIG. 6, the drive substrate 61 on which the transparent electrode 64 is formed is configured to be transparent or translucent. Is done. The transparent electrode 64 may be either a cathode or an anode, but since ITO is usually used, it is generally an anode.
[0057]
Hereinafter, a method for producing an optical element of the present invention will be described with reference to the drawings.
[0058]
1 to 3 are process diagrams schematically showing a method for producing an optical element of the present invention. Each step will be described below. The following steps (a) to (j) correspond to (a) to (j) in FIGS. 1 to 3, (a-1) to (j-1) on the left side of the drawing are schematic plan views, and (a-2) to (j-2) on the right side of the drawing are (a-1). It is AB sectional schematic drawing of (j-1). In the figure, 1 is a support substrate, 2 is a photosensitive resin composition layer, 3 is a partition pattern, 4 is an opening of the partition pattern 3, 5 is a partition, 6 is ink, and 7 is a pixel.
[0059]
Step (a)
A support substrate 1 is prepared. The support substrate 1 is a transparent substrate 41 when the color filter illustrated in FIG. 4 is manufactured, and a glass substrate is generally used. However, for the purpose of constituting a liquid crystal element, desired transparency and mechanical strength are used. A plastic substrate or the like can be used as long as it has the necessary characteristics.
[0060]
Further, when the EL element illustrated in FIG. 6 is manufactured, the support substrate 1 is the drive substrate 61 on which the transparent electrode 64 is formed. When the light is irradiated from the substrate side as shown in FIG. A transparent substrate such as a glass substrate is used for 61.
[0061]
Step (b)
A photosensitive resin composition layer 2 for forming the partition walls 5 is formed on the support substrate 1. The partition wall 5 according to the present invention corresponds to the black matrix 42 in the case of the color filter of FIG. 4, and corresponds to the partition wall 62 in the case of the EL element of FIG. In the case of manufacturing a color filter, the partition wall 5 is preferably a light-shielding layer that shields light between adjacent pixels as shown by 42 in FIG. 4, and in this case, a black matrix 42 as shown in FIG. Or a black stripe. In addition, a light shielding layer can also be used when manufacturing an EL element.
[0062]
In the present invention, the photosensitive resin composition used to form the partition walls 5 includes epoxy resins, acrylic resins, polyimide resins including polyamideimide, urethane resins, polyester resins, polyvinyl resins, and the like. Although a photosensitive resin material can be used, it preferably has a heat resistance of 250 ° C. or higher, and from this point, an epoxy resin, an acrylic resin, and a polyimide resin are preferably used. Moreover, it can be used regardless of form, such as a liquid material and a dry film material.
[0063]
Moreover, when making this partition 5 into a light shielding layer, the photosensitive resin composition layer 2 is formed using the black photosensitive resin composition which disperse | distributed the light shielding agent in the said photosensitive resin composition. As the light-shielding agent, as described later, it is desirable to use carbon black in order to obtain high ink repellency and appropriate surface roughness of the partition wall 5, and as the carbon black, channel black, roller black, disk black Manufactured by the contact method called gas furnace black, manufactured by the furnace method called oil furnace black, manufactured by the thermal method called thermal black, acetylene black In particular, channel black, gas furnace black, and oil furnace black are preferable. If necessary, a mixture of R, G, and B pigments may be added. Moreover, the black resist generally marketed can also be used. If necessary, a light-shielding layer with a high resistance may be used.
[0064]
The photosensitive resin composition layer 2 can be formed by a method such as spin coating, roll coating, bar coating, spray coating, dip coating, slit coating, or printing.
[0065]
Step (c)
The photosensitive resin composition layer 2 is exposed, developed and patterned by a normal photolithography method to form a partition pattern 3 having a plurality of openings 4.
[0066]
Step (d)
The support substrate 1 on which the partition pattern 3 is formed is subjected to light irradiation treatment. This treatment is for preventing generation of wrinkles on the partition wall surface due to thermal contraction in the subsequent heat treatment (post-bake treatment), sagging of the partition wall cross section, and white spots due to distortion of the cross-sectional shape. In this step, the entire surface is preferably exposed from both the front surface (partition pattern 3 formation side) and the back surface of the substrate 1.
[0067]
Step (e)
The exposed partition pattern 3 is subjected to heat treatment and cured to form the partition wall 5. In the present invention, since the light irradiation treatment is performed in the previous step, the cross-sectional shape of the obtained partition wall 5 in the normal direction of the substrate 1 substantially holds the cross-sectional shape of the partition wall pattern 3 immediately after patterning in the step (c). Therefore, when the ink 6 is applied to the opening 4 in a subsequent process, the side surfaces of the ink 6 and the partition wall 5 are in good contact with each other, and white spots are prevented.
[0068]
As a cross-sectional shape in the normal direction of the substrate 1 of the partition wall 5 in the present invention, the pattern line width L on the upper surface₁, Bottom pattern line width L₂And the height T of the partition wall is T ≧ | L₂-L₁It is preferable that at least a part of the side wall of the partition wall and the pixel 7 are in contact with each other. The sectional shape of the partition wall 5 is T <| L₂-L₁In the case of | / 2, white spots are likely to occur after the pixels are formed, resulting in poor appearance.
[0069]
Step (f)
The supporting substrate 1 on which the partition walls 5 are formed is subjected to an ink affinity process. As the lyophilic process, a dry etching process is preferable. Specifically, a gas containing at least one selected from oxygen, argon, and helium is introduced, and the support substrate is used in a reduced pressure atmosphere or an atmospheric pressure atmosphere. 1 is subjected to reduced pressure plasma treatment or atmospheric pressure plasma treatment in which plasma irradiation is performed.
[0070]
By performing the dry etching process, contaminants adhering to the surface of the support substrate 1 in the step of forming the partition wall 5 are removed, and the surface is cleaned to improve the wettability (ink affinity) of the ink 6 in the subsequent process. The ink 6 can be diffused well in the opening 4. Furthermore, the dry etching process roughens the surface layer of the partition wall 5 and improves the ink repellency.
[0071]
Step (g)
The partition wall 5 is subjected to fluorination treatment, preferably plasma treatment for introducing a gas containing at least fluorine atoms and irradiating the partition wall 5 with plasma. By the plasma treatment, fluorine or a fluorine compound in the introduced gas enters the surface layer of the partition wall 5 and the ink repellency of the surface layer of the partition wall 5 is increased.
[0072]
In particular, when the partition walls 5 are made of a photosensitive resin composition containing carbon black, very high ink repellency is exhibited. The reason is considered that carbon black is exposed on the surface of the partition wall 5 by the dry etching treatment in the previous step (f), and fluorine or a fluorine compound is bonded to the carbon black by the plasma treatment in this step. Therefore, in the present invention, it is desirable to include carbon black in the partition walls 5.
[0073]
The gas introduced at this step containing at least fluorine atoms is CF._Four, CHF_Three, C₂F₆, SF₆, C_ThreeF₈, C_FiveF₈It is preferable to use at least one halogen gas selected from In particular, C_FiveF₈(Octafluorocyclopentene) has zero ozone depletion ability and has an atmospheric lifetime (CF less than that of conventional gas)._Four: 50,000 years, C_FourF₈: 3200) 0.98, very short. Therefore, the global warming potential is 90 (CO₂= 100 years integrated value = 2) and (CF) compared with conventional gas_Four: 6500, C_FourF₈: 8700) Very small, extremely effective for protecting the ozone layer and the global environment, and desirable for use in the present invention.
[0074]
Further, as the introduced gas, a gas such as oxygen, argon, or helium may be used in combination as necessary. In the present invention, the CF_Four, CHF_Three, C₂F₆, SF₆, C_ThreeF₈, C_FiveF₈At least one halogen gas selected from₂When the mixed gas is used, the degree of ink repellency in this step can be controlled. However, in the mixed gas, O₂If the mixing ratio exceeds 30%, O₂Oxidation reaction due to becomes dominant and the effect of improving ink repellency is hindered.₂When the mixing ratio exceeds 30%, damage to the resin becomes significant.₂It is necessary to use in a range where the mixing ratio is 30% or less.
[0075]
As a method of generating plasma in this process and the previous dry etching process, methods such as low frequency discharge, high frequency discharge, and microwave discharge can be used. Pressure, gas flow rate, discharge frequency, and processing during plasma irradiation can be used. Conditions such as time can be arbitrarily set.
[0076]
The degree of ink repellency after the fluorination treatment on the surface of the partition wall 5 according to the present invention is preferably such that the contact angle measured with pure water is 110 ° or more. If the contact angle is less than 110 °, color mixing tends to occur, and a large amount of ink cannot be applied. In particular, when a color filter is manufactured, it is difficult to manufacture a color filter with high color purity. In the conventional method, it is difficult to increase the ink repellency on the surface of the partition wall 5 to 110 ° or more, and PTFE (polytetrafluoroethylene) used as a high ink repellency material is slightly less than 110 °.
[0077]
In the present invention, the partition wall 5 is formed of a photosensitive resin composition containing carbon black, subjected to a dry etching process, and then subjected to a plasma treatment. It can be as high as ° or more, and is preferably 120 ° or more and 135 ° or less. By setting the ink repellency on the surface of the partition wall 5 to 135 ° or less, white spots can be prevented when the amount of ink is small.
[0078]
The ink affinity on the surface of the support substrate 1 is preferably such that the contact angle measured with pure water is 20 ° or less. By setting the contact angle with respect to pure water to 20 ° or less, the ink spreads well on the surface of the support substrate 1 and no white spots occur even if the ink repellency on the surface of the partition wall 5 is high. In particular, the angle is preferably 10 ° or less.
[0079]
Step (h)
The ink spreading property improving process is performed by bringing the supporting substrate 1 subjected to the plasma process into contact with water. By performing the ink spreading property improving process, the ink is sufficiently spread to the opening even when a small amount of ink is applied.
[0080]
The water used in this step is preferably pure water. The method for bringing the support substrate 1 into contact with water is not particularly limited as long as it is a method for bringing water and the support substrate 1 into complete contact, such as immersion in water or showering of water. However, in the case where the partition wall 5 on the support substrate 1 has a complicated pattern shape, or from the viewpoint of sufficiently making contact with water at a minute part such as a boundary part or a corner part of the partition wall 5 and the opening 4, Dipping in a sonic bath or showering with fine and high-pressure water droplets is preferred.
[0081]
Furthermore, the temperature of water used for the ink spreading property improving process is preferably 20 to 60 ° C. from the viewpoint of effectively modifying the surface of the opening 4.
[0082]
Step (i)
The ink 6 is applied to the region (opening 4) surrounded by the partition wall 5 from an inkjet head (not shown) using an inkjet recording apparatus. As the ink jet, a bubble jet type using an electrothermal transducer as an energy generating element, a piezo jet type using a piezoelectric element, or the like can be used. The ink 6 includes a colorant for each color so as to form a colored portion of R, G, and B after curing in the case of a color filter. In the case of an EL element, the ink 6 emits light upon application of a voltage after curing. A material containing a light emitting material for forming a light emitting layer is used. In any case, the ink 6 preferably contains at least a curing component, water, and a solvent. Hereinafter, the composition of the ink used when the color filter is produced by the production method of the present invention will be described in more detail.
[0083]
[1] Colorant
As the colorant to be contained in the ink in the present invention, both dyes and pigments can be used. However, when a pigment is used, it is necessary to add a separate dispersant in order to uniformly disperse in the ink. A dye-based colorant is preferably used because the ratio of the colorant in the total solid content becomes low. Moreover, it is preferable that it is the same amount or less as the addition amount of a coloring agent with the hardening component mentioned later.
[0084]
[2] Curing component
In consideration of process resistance, reliability, and the like in the subsequent step, it is preferable to contain a component that is cured by a heat treatment or light irradiation and immobilizes the colorant, that is, a crosslinkable monomer or polymer. In particular, it is preferable to use a curable resin composition in consideration of heat resistance in the subsequent process. Specifically, for example, as a base resin, acrylic resin having a functional group such as hydroxyl group, carboxyl group, alkoxy group, amide group, silicone resin; or cellulose derivatives such as hydroxypropylcellulose, hydroxyethylcellulose, methylcellulose, carboxymethylcellulose, or These modified products; or vinyl polymers such as polyvinyl pyrrolidone, polyvinyl alcohol, and polyvinyl acetal. Furthermore, it is possible to use a crosslinking agent and a photoinitiator for curing these base resins by light irradiation or heat treatment. Specifically, melamine derivatives such as methylolated melamine are used as crosslinking agents, and dichromate, bisazide compounds, radical initiators, cationic initiators, anionic initiators, etc. are used as photoinitiators. Is possible. Moreover, these photoinitiators can also be used by mixing multiple types or combining with another sensitizer.
[0085]
[3] Solvent
As the ink medium used in the present invention, a mixed solvent of water and an organic solvent is preferably used. As water, it is preferable to use ion-exchanged water (deionized water) instead of general water containing various ions.
[0086]
Examples of the organic solvent include alkyl alcohols having 1 to 4 carbon atoms such as methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, sec-butyl alcohol, tert-butyl alcohol; dimethylformamide, dimethylacetamide Amides such as acetone, ketones such as acetone and diacetone alcohol, or ethers such as tetrahydrofuran and dioxane, polyalkylene glycols such as polyethylene glycol and polypropylene glycol, ethylene glycol, propylene glycol, butylene glycol, and triethylene Alkylene glycols containing 2 to 4 carbons such as glycol, thiodiglycol, hexylene glycol, diethylene glycol, etc. Glycerins; Lower alkyl ethers of polyhydric alcohols such as ethylene glycol monomethyl ether, diethylene glycol methyl ether, triethylene glycol monomethyl ether; N-methyl-2-pyrrolidone, 2-pyrrolidone, etc. Is preferred.
[0087]
In addition to the above components, two or more kinds of organic solvents having different boiling points may be used in combination to obtain an ink having a desired physical property value, if necessary, or a surfactant, antifoaming agent, preservative. Etc. may be added.
[0088]
Step (j)
The pixel 7 is formed by performing necessary processing such as heat treatment and light irradiation, removing the solvent component in the ink 6 and curing it.
[0089]
Furthermore, in the case of a color filter, as described above, a protective layer and a transparent conductive film are formed as necessary. As the protective layer in this case, a photocuring type, a thermosetting type, or a photothermal combined curing type resin material, or an inorganic film formed by vapor deposition, sputtering, or the like can be used. Any material can be used as long as it has transparency and can withstand a subsequent transparent conductive film formation process, alignment film formation process, and the like. Moreover, you may form a transparent conductive film directly on a coloring part, without passing through a protective layer.
[0090]
When manufacturing an organic EL element, a necessary member such as a metal layer serving as a cathode is formed on the colored portion 7.
[0091]
【Example】
Example 1
[Formation of black matrix]
After applying a black resist containing carbon black (“CK-S171 resist” manufactured by Fujifilm Orin) on a glass substrate (Corning “1737”), and performing predetermined exposure and development, the front and back surfaces of the substrate The whole surface was irradiated with light. The light source is Deep UV and the irradiation amount is 32000mJ / cm.²It carried out in. The light source can be used as long as it can generate light including a wavelength in the range of 200 nm to 550 nm. Thereafter, a post-bake treatment was performed to produce a black matrix (partition) having a rectangular opening with a film thickness of 2 μm and 75 μm × 225 μm.
[0092]
(Evaluation of cross-sectional shape)
The cross-sectional shape of the pattern was evaluated for the black matrix substrate after the post-baking using an optical microscope. Pattern line width L on the upper surface of the partition wall₁Is reflected by the microscope, and the pattern line width L on the bottom surface₂Was observed with transmitted light, and the height T was measured using a stylus type surface roughness meter manufactured by Tecnor.
L₁= 21.30 μm, L₂= 22.55 μm, T = 1.69 μm,
｜ L₂-L₁| /2=0.625 <T.
[0093]
[Ink adjustment]
Using an acrylic copolymer having the composition shown below as a thermosetting component, R, G, and B inks were prepared with the following compositions.
[0094]
Curing component
50 parts by weight of methyl methacrylate
30 parts by weight of hydroxyethyl methacrylate
N-methylolacrylamide 20 parts by weight
R ink
C. I. Acid Orange 148 3.5 parts by weight
C. I. Acid Red 289 0.5 parts by weight
30 parts by weight of diethylene glycol
20 parts by weight of ethylene glycol
40 parts by weight of ion exchange water
6 parts by weight of the above curing component
G ink
C. I. Acid Yellow 23 2 parts by weight
2 parts by weight of zinc phthalocyanine sulfoamide
30 parts by weight of diethylene glycol
20 parts by weight of ethylene glycol
40 parts by weight of ion exchange water
6 parts by weight of the above curing component
B ink
C. I. Direct Blue 199 4 parts by weight
30 parts by weight of diethylene glycol
20 parts by weight of ethylene glycol
40 parts by weight of ion exchange water
6 parts by weight of the above curing component
[0095]
[Parent ink processing]
The glass substrate (black matrix substrate) on which the black matrix was formed was dry-etched under the following conditions using a cathode coupling parallel plate plasma processing apparatus.
[0096]
Gas used: O₂
Gas flow rate: 80sccm
Pressure: 8Pa
RF power: 150W
Processing time: 30 sec
[0097]
[Fluorination treatment]
After the dry etching process was completed, a plasma process was performed on the black matrix substrate under the following conditions in the same apparatus.
[0098]
Gas used: CF_Four
Gas flow rate: 80sccm
Pressure: 50Pa
RF power: 150W
Processing time: 30 sec
[0099]
[Evaluation of ink repellency]
Using a liquid crystal glass cleaning / processing inspection device “LCD-400S” manufactured by Kyowa Interface Co., Ltd., the contact angle with pure water was measured for the black matrix substrate after the plasma treatment. The black matrix surface was measured on a frame having a width of 5 mm provided around the fine pattern, and the glass substrate surface was measured at a location where the black matrix further outside the frame was not provided. The contact angle for each pure water is
Glass substrate surface: 6 °
Black matrix surface: 126 °
Met.
[0100]
[Evaluation of surface roughness]
The surface roughness of the black matrix surface was evaluated by measuring the average roughness (Ra) on a frame with a width of 5 mm in the same manner as the contact angle with pure water using a stylus type surface roughness meter “FP-20” manufactured by Tecnor did. As a result, the average roughness (Ra) of the black matrix surface was 4.4 nm.
[0101]
[Evaluation of ink spreading properties]
The ink spreading property of the black matrix substrate after the plasma treatment was evaluated. When ink was applied to the opening in the 20 pl fine pattern from the ink head and observed with an optical microscope, the diameter of the ink droplet was 50 μm. Although the substrate was left for a while, the ink droplets did not spread out.
[0102]
[Ink spreadability improvement processing]
The black matrix substrate after the plasma treatment was immersed in an ultrasonic pure water bath, and an ink spreading property improving treatment was performed. The processing conditions were as follows.
[0103]
Pure water temperature: 30 ° C
Ultrasonic frequency: 40 kHz
Processing time: 2 min
[0104]
[Evaluation of ink repellency]
In order to confirm whether the ink repellency on the black matrix surface was not impaired by the ink spreading property improving process, the contact angle with respect to pure water was measured for the black matrix substrate after the ink spreading property improving process. The measurement location was the same as the location measured before the ink spreading property improving treatment. The contact angle for each pure water is
Glass substrate surface: 7 °
Black matrix surface: 124 °
Met.
[0105]
[Evaluation of ink spreading properties]
The ink spreading property was evaluated for the black matrix substrate after the ink spreading property improving process. The evaluation method was the same as the measurement before the ink spreading property improving process. When the diameter of the applied ink droplet was observed with an optical microscope, the ink was sufficiently spread in the opening and it was difficult to find the end of the droplet.
[0106]
(Preparation of colored part)
Using an ink jet recording apparatus equipped with an ink jet head having a discharge amount of 20 pl, the R, G, and B inks are applied at 200 to 800 pl per opening on the black matrix substrate that has been subjected to the ink spreading property improvement process according to the above procedure. The amount was changed every 100 pl in the range. Next, heat treatment was performed at 90 ° C. for 10 minutes and subsequently at 230 ° C. for 30 minutes to cure the ink to form colored portions (pixels), and seven types of color filters with different ink application amounts were produced.
[0107]
[Evaluation of color mixing, white spots, and flatness of colored areas]
The white spots of the obtained color filters were evaluated by observation with an optical microscope. In addition, for the evaluation of flatness, in the case where 300 pl of ink was applied per opening, the surface roughness meter used in the evaluation of the surface roughness was used, and the high color from the glass surface of the colored portion central portion of each color D_tAnd the height d from the surface of the glass substrate at the part of the colored part in contact with the black matrix_bDifference (d_t-D_b) And -0.5 μm ≦ (d_t-D_b) ≦ 0.5 μm, flat, (d_t-D_b) <-0.5 μm if concave, (d_t-D_b)> 0.5 μm, it was evaluated as a convex shape.
[0108]
As a result, no color mixing or white spots were observed in all the color filters of this example, and the colored portion surface was flat.
[0109]
(Example 2)
A color filter was produced in the same manner as in Example 1 except that a film-type dry resist was used as a black resist containing carbon black. The contact angle for pure water of the black matrix substrate after the ink spreading property improvement treatment is
Glass substrate surface: 5 °
Black matrix surface: 128 °
Met. When the ink spreading property was also evaluated, the ink was sufficiently spread in the opening with 20 pl of ink. The average roughness (Ra) of the black matrix surface was 10.3 nm. For all the color filters obtained in this example, no color mixing or white spots were observed, and the colored portion surface was flat.
[0110]
Example 3
CF in plasma processing_FourAnd O₂A color filter was produced in the same manner as in Example 1 except that the mixed gas was introduced at a gas flow rate of 64 sccm and 16 sccm, respectively. The contact angle for pure water of the black matrix substrate after the ink spreading property improvement treatment is
Glass substrate surface: 7 °
Black matrix surface: 133 °
Met. When the ink spreading property was also evaluated, the ink was sufficiently spread in the opening with 20 pl of ink. The average roughness (Ra) of the black matrix surface was 5.2 nm. For all the color filters obtained in this example, no color mixing or white spots were observed, and the colored portion surface was flat.
[0111]
(Example 4)
A color filter was produced in the same manner as in Example 1 except that “CT-2000L” manufactured by Fuji Film Orin, which is a transparent photosensitive resin not containing carbon black, was used instead of the black resist used in Example 1. The contact angle with pure water of the transparent matrix substrate after the ink spreading property improving process is
Glass substrate surface: 6 °
Transparent matrix surface: 102 °
Met. When the ink spreading property was also evaluated, the ink was sufficiently spread in the opening with 20 pl of ink. The average roughness (Ra) of the transparent matrix surface was 1.5 nm.
[0112]
For all the color filters obtained in this example, no color mixing or white spot was observed. Moreover, since the colored part surface was convex shape, the density was slightly reduced at the boundary part between the colored part and the transparent matrix.
[0113]
(Example 5)
A color filter was prepared in the same manner as in Example 1 except that the substrate that had been subjected to plasma treatment by the same method as in Example 1 had a pure water temperature of 50 ° C. and a processing time of 30 sec. Was made. The contact angle for pure water of the black matrix substrate after the ink spreading property improvement treatment is
Glass substrate surface: 8 °
Black matrix surface: 124 °
Met. When the ink spreading property was also evaluated, the ink was sufficiently spread in the opening with 20 pl of ink. The average roughness (Ra) of the black matrix surface was 10.5 nm. For all the color filters obtained in this example, no color mixing or white spots were observed, and the colored portion surface was flat.
[0114]
(Example 6)
A substrate subjected to plasma treatment by the same method as in Example 1 was subjected to an ink spreading property improving process using a high-pressure spray cleaning device to produce a color filter. Pure water is used for the high-pressure spray, and the spray pressure is 6.86 × 10.⁶Pa was set. The contact angle for pure water of the black matrix substrate after the ink spreading property improvement treatment is
Glass substrate surface: 5 °
Black matrix surface: 124 °
Met. When the ink spreading property was also evaluated, the ink was sufficiently spread in the opening with 20 pl of ink. The average roughness (Ra) of the black matrix surface was 9.9 nm. For all the color filters obtained in this example, no color mixing or white spots were observed, and the colored portion surface was flat.
[0115]
(Example 7)
The light irradiation treatment of Example 1 was 22000 mJ / cm, respectively.²A color filter was prepared in the same manner as in Example 1 except that. In evaluating the cross-sectional shape of the black matrix,
L₁= 20.82 μm, L₂= 22.52 μm, T = 1.70 μm
｜ L₂-L₁| /2=0.85 <T.
[0116]
The contact angle for pure water of the black matrix substrate after the ink spreading property improvement treatment is
Glass substrate surface: 8 °
Black matrix surface: 122 °
Met. When the ink spreading property was also evaluated, the ink was sufficiently spread in the opening with 20 pl of ink. The average roughness (Ra) of the black matrix surface was 4.6 nm. Further, since the colored portion surface was convex, the density was slightly reduced at the boundary between the colored portion and the black matrix.
[0117]
(Example 8)
On the TFT driving substrate formed by a thin film process, in which multiple layers of wiring films and insulating films are laminated, ITO (transparent electrode) is formed to a thickness of 40 nm as a transparent electrode on a pixel (light emitting layer) unit basis, and by photolithography Patterning was performed according to the pixel shape.
[0118]
Next, partition walls filling the light emitting layer were formed. After applying a transparent photosensitive resin ("CT-2000L" manufactured by Fuji Film Orin) and performing exposure and development processes in the same manner as in Example 1, the above-mentioned ITO transparent electrode was subjected to a light irradiation process and a post-bake process. A transparent matrix having a rectangular opening with a film thickness of 0.4 μm and 75 μm × 225 μm was prepared. Next, the substrate was subjected to O under the same conditions as in Example 1.₂Etching using CF and CF_FourPlasma treatment using was performed. Subsequently, an ink spreading property improving process was performed using a high-pressure spray cleaning device. When measuring the contact angle for pure water on the ITO transparent electrode and on the transparent matrix,
On ITO transparent electrode: 17 °
On transparent matrix: 101 °
Met. In order to evaluate the ink spreading property on the ITO transparent electrode, when 20 pl of ink was applied, the ink was sufficiently wet spread and it was difficult to measure the ink droplet diameter.
[0119]
Next, a light emitting layer was formed in the partition wall of the substrate. As the ink, an electron transporting 2,5-bis (5-tert-butyl-2-benzoxazolyl) -thiophene [electron transporting blue light-emitting dye having a fluorescence peak of 450 nm and one of the emission center forming compounds is used. It is. Hereinafter referred to as “BBOT”) in a hole transporting host compound comprising poly-N-vinylcarbazole (molecular weight: 150,000, manufactured by Kanto Chemical Co., Inc., hereinafter referred to as “PVK”) at a concentration of 30% by weight. Both were dissolved in a dichloroethane solution so that the molecules could be dispersed. Nile red, another luminescent center forming compound, was dissolved in the dichloroethane solution of PVK-BBOT at 0.015 mol% to form an ink, filled in the opening of the transparent matrix by an ink jet method, dried, and 200 nm in thickness. The light emitting layer was formed. At this time, each pixel (light emitting layer) was independent, and the ink was not mixed between adjacent pixels. Further, Mg: Ag (10: 1) was vacuum deposited thereon to form a Mg: Ag cathode having a thickness of 200 nm to obtain an organic EL device.
[0120]
When a voltage of 18 V was applied to each pixel of the obtained EL element, 480 cd / m²Uniform white light emission was obtained.
[0121]
(Comparative Example 1)
A color filter was produced in the same manner as in Example 1 except that the ink spreading property improvement process was not performed. The contact angle of pure water on the black matrix substrate is
Glass substrate surface: 6 °
Black matrix surface: 129 °
Met. The ink spreading property was also evaluated. As a result, the ink droplet diameter was 53 μm without wet spreading with 20 pl of ink. The average roughness (Ra) of the black matrix surface was 5.5 nm. In all the color filters obtained in this example, white spots were observed in all the colored portions. In addition, white spots were also observed in the color filter having an ink application amount of 400 pl or more. The flatness of the colored portion surface could not be evaluated because white spots occurred.
[0122]
(Comparative Example 2)
A color filter was produced in the same manner as in Example 1 except that the dry etching treatment and the plasma treatment were not performed. The contact angle of pure water on the black matrix substrate is
Glass substrate surface: 62 °
Black matrix surface: 78 °
Met. The average roughness (Ra) of the black matrix surface was 2.0 nm. In all the color filters obtained in this example, white spots were observed in all the colored portions. In addition, color mixing was observed for the color filter having an ink application amount of 400 pl or more. The flatness of the colored portion surface could not be evaluated because white spots occurred.
[0123]
(Comparative Example 3)
When a color filter was produced in the same manner as in Example 1 except that the light irradiation after the black matrix pattern was not formed, wrinkles occurred in a part of the black matrix.
[0124]
【The invention's effect】
As described above, according to the present invention, an optical element having pixels with no color mixture or white spots can be manufactured with a simple process by an inkjet method with a high yield, and a color filter without density unevenness in the colored portion, It is possible to provide an EL element with no uneven luminance in the light emitting layer with a high yield. Therefore, a liquid crystal element having excellent color display characteristics can be provided at a lower cost by using the color filter.
[Brief description of the drawings]
FIG. 1 is a process diagram of an embodiment of a method for producing an optical element of the present invention.
FIG. 2 is a process diagram of an embodiment of a method for producing an optical element of the present invention.
FIG. 3 is a process diagram of an embodiment of a method for producing an optical element of the present invention.
FIG. 4 is a schematic cross-sectional view of an example of a color filter that is an embodiment of the optical element of the present invention.
FIG. 5 is a schematic cross-sectional view of an embodiment of a liquid crystal element of the present invention.
FIG. 6 is a schematic cross-sectional view of an example of an EL element that is an embodiment of the optical element of the present invention.
FIG. 7 is a conceptual diagram of color mixing that occurs in a method of manufacturing an optical element by an ink jet method.
FIG. 8 is a conceptual diagram of white spots that occur in a method of manufacturing an optical element by an ink jet method.
[Explanation of symbols]
1 Support substrate
2 Photosensitive resin composition layer
3 Bulkhead pattern
4 openings
5 Bulkhead
6 Ink
7 pixels
41 Transparent substrate
42 Black Matrix
43 pixels
44 protective layer
47 Common electrode
48 Alignment film
49 LCD
51 Counter substrate
52 Pixel electrode
53 Alignment film
61 Driving board
62 Bulkhead
63 Light emitting layer
64 Transparent electrode
66 Metal layer
71 Support substrate
73 Black Matrix
76 ink
78

Claims (10)

A method of manufacturing an optical element having at least a plurality of pixels on a support substrate and a partition wall positioned between adjacent pixels,
Forming a photosensitive resin composition layer on a support substrate, pattern exposure and development to form a partition pattern, a step of subjecting the partition pattern to light irradiation, and a heat treatment to the partition pattern irradiated with light. A step of forming a partition wall, a step of subjecting the support substrate to an ink repellency treatment, a step of subjecting the partition wall and the support substrate to a fluorination treatment, and an ink spreading property for bringing water into contact with the surface of the support substrate. A step of performing an improvement process, and a step of applying ink to a region surrounded by the partition wall by an inkjet method to form a pixel, at least in this order,
The method for producing an optical element, wherein the fluorination treatment is plasma treatment in which a gas containing at least fluorine atoms is introduced to perform plasma irradiation .   The method for producing an optical element according to claim 1, wherein the partition pattern forming step is a step of photolithography using a liquid resist or a film resist.   The method of manufacturing an optical element according to claim 1, wherein the light irradiation treatment of the partition wall pattern irradiates light from both surfaces of the support substrate.   The ink-repellent treatment is a dry etching treatment in which a gas containing at least one selected from oxygen, argon, and helium is introduced, and the support substrate is irradiated with plasma in a reduced pressure atmosphere or an atmospheric pressure atmosphere. Item 4. A method for producing an optical element according to any one of Items 1 to 3. The gas introduced in the plasma treatment is a mixed gas of at least one halogen gas selected from CF ₄ , SF ₆ , CHF ₃ , C ₂ F ₆ , C ₃ F ₈ , and C ₅ F ₈ and O ₂ gas. There, method of manufacturing an optical element according to any one of claims 1 to 4 the mixing ratio of O ₂ is 30% or less. The ink spreading performance improvement process, while contacting the water to support a substrate, method of manufacturing an optical element according to any one of claims 1 to 5, which is a process of irradiating the ultrasonic waves. The manufacturing method of the optical element of any one of Claims 1-6 which forms the said partition with a black photosensitive resin composition. The ink of at least the curing component, water, method of manufacturing an optical element according to any one of claims 1 to 7 containing an organic solvent. The method for producing an optical element according to claim 8 , wherein the ink contains a colorant, and a color filter in which a pixel is a colored portion is produced. The method for producing an optical element according to claim 8 , wherein the electroluminescent element is produced in which the ink contains a light emitting material and the pixel is a light emitting layer.

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