JP4035880B2 - Manufacturing method of heat-resistant color filter - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present invention is applied to display devices such as field emission displays, fluorescent display devices, discharge display panels, and color liquid crystal displays, and solid-state imaging devices, and is used for reducing reflectance, improving contrast, and controlling spectral characteristics. The present invention relates to a color filter.
[0002]
[Prior art]
  The color liquid crystal display uses a color filter having spectral characteristics of desired color light in order to display a color image. These use a resin layer colored with an organic pigment or an organic dye as a color filter by a dyeing method, a pigment dispersion method, a printing method, or the like. (See M. Tani, et al: “LCD Color Filters: Characteristics and Future Issues”, SID 95 SEMINA LECTURE (1995), etc.)
[0003]
  In addition, in cathode ray tube display devices (CRT), low-speed electron beam fluorescent display panels, discharge display panels, etc., it has been proposed to use a color filter to reduce reflectance and improve contrast when images are displayed. . (See T. Ito, et al: “Microfilter ™” Color CRT, SID 95 Digest, p. 25 (1995), etc.)
[0004]
  As described above, in a display device, a solid-state imaging device, and the like, using a color filter for the purpose of reducing reflectance and controlling spectral characteristics is a useful means for improving color display image quality.
[0005]
  By the way, in the case of a field emission display, a process of melting a low-melting glass at 400 ° C. or higher and sealing two glass substrates is used. Therefore, when a color filter for a liquid crystal display is used as a color filter for a field emission display, the organic material constituting the color filter undergoes reactions such as combustion and decomposition by a high-temperature manufacturing process, and the characteristics of the color filter In other words, it is impossible to achieve the purposes of improving display contrast, reducing reflectance, and controlling spectral characteristics.
[0006]
  As one method for solving this problem, a color filter that can cope with a high-temperature manufacturing process by dispersing an inorganic pigment in a low-melting glass has been proposed.
(See Sakai et al .: “Ultra-low reflectance color display discharge panel (3)” Television Society Technical Report, ED993, IPD113-8 (1986-11), etc.)
[0007]
  As a material constituting the color filter layer, a glass material in which an inorganic color pigment is dispersed is generally applied. As a pattern forming method, a low melting point glass powder, an inorganic pigment, and a paste made of a resin binder or the like for temporarily fixing these materials on a transparent substrate are screen-printed on the pixel portion on the transparent substrate, and this printing is performed. The patterned layer is baked at about 600 ° C. The color filter layer is obtained by a method in which components such as the resin binder are burned out and the low melting point glass powder is melted to coat and fix the inorganic pigment on the transparent substrate. In this case, since the color filter layer is entirely composed of an inorganic material, it can have durability of a high-temperature process related to manufacturing.
[0008]
  The screen printing method used as a method for forming the color filter layer is to supply the paste onto a screen printing plate having openings of a predetermined pattern, and rub the paste from the openings by rubbing with a flexible squeegee. This is a method of extruding and printing on a glass transparent substrate. Therefore, the screen plate expands and contracts according to conditions such as the temperature around the printing press, humidity, pressure applied to the squeegee and moving speed of the squeegee, the opening is easily deformed, and the formed pattern is easily distorted. is there. In addition, the thickness of the printed film that can be formed by controlling the film thickness, pattern shape, etc. in a single printing, such as a color filter, is limited to about 10 μm. In order to form a film, it is necessary to repeatedly print the same pattern. However, each time screen printing is performed, the above-described difference in printing conditions occurs, and the opening portion is likely to be deformed, and it is usually difficult to print a pattern in which the printing positions are completely matched.
[0009]
  Further, the color filter has a thickness of about 10 μm due to the low-melting glass and pigment constituting the color filter, and a step corresponding to the thickness is formed on the transparent substrate, and disconnection of electrodes and the like to be formed later It is easy to cause. For this reason, the pattern obtained by printing a large number of times causes problems not only in resolution and dimensional accuracy but also in productivity.
[0010]
  In order to solve the problem related to the resolution of the pattern, it is possible to improve the pattern resolution by forming a pattern by a photolithography process using a photosensitive paste made of a color pigment and a low melting point glass. . However, like the paste used in screen printing, the pattern obtained has a certain thickness due to the low melting point glass and the pigment, so it is difficult to eliminate the step on the substrate surface.
[0011]
  Under such a technical background, the present applicants have previously filed an application regarding a color filter and a manufacturing method thereof. This is done by forming a pattern of only the color filter constituent material on the transparent substrate into a predetermined shape, and then providing a patterned overcoat layer and a light-transmitting overcoat layer on the periphery. Thus, a color filter is configured. (See Japanese Patent Application No. 7-298200)
[0012]
  According to this method, the color filter layer is composed of a pigment exhibiting a desired color spectral characteristic and a light-transmitting overcoat material provided on the periphery thereof. The step on the transparent substrate can be reduced depending on the particle size and the pigment and the film thickness of the light-transmitting overcoat layer provided around the pigment. That is, the level difference between the portion where the color filter is formed and the portion where the color filter is not formed is reduced as compared with the conventional method in which a color filter is obtained by patterning a glass material in which an inorganic coloring pigment or the like is dispersed. Therefore, when a color filter layer is formed on a transparent substrate such as a field emission display, and then an electrode or a dielectric layer is formed on the transparent substrate, disconnection or a defect can be prevented. Even when formed in the lower layer of the filter, the dielectric layer formed in the upper layer of the color filter can be formed smoothly, and the quality and productivity of the color filter can be improved.
[0013]
  In order to form a color filter with few steps, it is necessary to form a pattern made only of pigment. In order to perform this pattern formation at the pattern shape and pattern formation position as designed, it is desirable to form a pattern with a colored photosensitive composition by photolithography, and binder resin or the like causes pattern shrinkage or peeling during firing. It is necessary to be burned away without forming a pattern of only colored pigments.
[0014]
[Problems to be solved by the invention]
  However, in this method, when a color filter is formed after a black matrix is formed on a transparent substrate in advance, there is no gap between the black matrix portion and the color filter portion, particularly when the black matrix is formed using a coloring material. For this reason (see FIG. 1), the adhesion between the substrate and the overcoat layer is not sufficient, and the adhesion in the subsequent process may not be sufficient. It is necessary to increase the adhesion of the overcoat layer.
[0015]
  Accordingly, the subject of the present invention is excellent in smoothness used for color separation, antireflection and display contrast improvement used in a display having a high temperature process in the manufacturing process, and heat resistance with improved substrate adhesion. It is to provide a color filter.
[0016]
[Means for Solving the Problems]
  That is, the present invention is a heat-resistant color filter formed using photolithography, in particular, a colored photosensitive composition is coated on a transparent substrate and patterned, and then an overcoat having light transmittance is formed on the pattern. A layer is formed and the pattern is baked and fixed. After the colored photosensitive composition is applied onto the substrate on which the fixed pattern is formed, the pattern is formed by exposure and development, and light is transmitted onto the formed pattern. An overcoat layer having a heat resistant color filter is formed.
[0017]
  The invention according to claim 1The colored photosensitive composition 1 is coated on a transparent substrate 8 and exposed, developed, and baked to form a fixed pattern 4, and then an overcoat layer 3 having light transmittance is formed on the fixed pattern 4. Then, the fixed pattern 4 is coated, and then fixed by baking. After the colored photosensitive composition 5 is applied on the entire surface of the transparent substrate 8 on which the fixed pattern 4 is formed, the pattern is exposed with a photomask and developed. This is performed for each of red, blue, and green, and then further baked to form a colored pattern 6, and the overcoat layer 3 on the fixing pattern 4 and the overcoat having light transmittance on the colored pattern 6 It is a method for producing a heat-resistant color filter, wherein the layer 7 is formed by firing.
  In this invention, the colored photosensitive composition is coated on a transparent substrate, exposed and developed to form a pattern, and then an overcoat layer having light transmittance is formed on the pattern to form a pattern. In the case where the colored photosensitive composition is fixed by firing, it is preferable that the colored photosensitive composition is in a state of only the coloring material in order to fix the pattern, and in particular, it is composed only of the coloring material by firing the pattern of the colored photosensitive composition. It is desirable.
[0018]
  The invention according to claim 2The method for producing a heat-resistant color filter according to claim 1, wherein a low melting point glass or a metal alkoxide is used as a material for baking and fixing the fixing pattern 4 as the light-transmitting overcoat layer 3. It is a manufacturing method of a property color filter. Here, the overcoat material formed on the pattern formed on the transparent substrate fixes the pattern and improves the adhesion of the pattern to the substrate. Here, in order to make the fixation of the pattern at a high temperature stronger and more stable, it is necessary to perform baking at a high temperature in advance, and as a heat-resistant color filter, it has light transmittance as well as resistance to high temperature baking. is required. Therefore, an inorganic material is preferable as a material to be applied, and it is particularly preferable to perform baking fixation using a low melting point glass or a metal alkoxide.
[0019]
  The invention according to claim 32. The method for producing a heat resistant color filter according to claim 1, wherein the overcoat layer 3 has a thickness of 10 [mu] m or less.
  Here, the material for forming the light-transmitting overcoat layer 3 on the formed pattern and baking and fixing the pattern is also applied to the portion where the pattern is not formed, and thus has a high light-transmitting property. It is desirable. In particular, when the film thickness after firing of the low melting point glass or metal alkoxide of the material for firing and fixing the pattern exceeds 10 μm, the transmittance at the display color light wavelength of the heat-resistant color filter is greatly lowered and insufficient. Therefore, it is difficult to satisfy the required characteristics of the color filter. Further, when the color filter is formed on a substrate on which electrodes or the like have already been formed, if the film thickness after firing of the low melting point glass or metal alkoxide of the material for firing and fixing the pattern exceeds 10 μm, the image can be stably displayed. It is difficult to ensure the distance between the electrodes necessary for display and the dielectric constant of the dielectric layer. Therefore, the low-melting-point glass, which is a material for fixing the pattern by forming a light-transmitting overcoat layer on the pattern, or the film thickness after firing of the metal alkoxide should be 10 μm or less. It is desirable to secure the sex.
[0020]
  Furthermore, the invention according to claim 4 is the method for producing a heat-resistant color filter according to claim 1, wherein the optical density of the fixed pattern 4 and the portion of the overcoat layer 3 thereon is 0.3 or more. This is a heat-resistant color filter. Here, when the optical density of the pattern formed by forming the light-transmitting overcoat layer 3 on the colorant pattern and fixed by baking is less than 0.3, the light shielding performance of the pattern is not sufficient, and the color filter pattern It is difficult to improve the performance of the color filter because a sufficient contrast difference with the portion cannot be secured. Therefore, in order to secure a sufficient contrast difference and to obtain the required performance of the color filter, the optical density of the pattern fixed by baking and fixing an overcoat layer having light transmittance on the colorant pattern is 0.3. The above is preferable.
[0021]
  Furthermore, the invention according to claim 5 is the heat resistant color filter according to claim 1, wherein the overcoat layer 7 is formed to have a thickness of 0.1 μm or more. Here, when the light-transmitting overcoat layer is formed on the formed fixing pattern and the colored pattern with a film thickness of less than 0.1 μm, a portion where the fixing pattern and the colored pattern are not sufficiently covered is generated. The portion that is not covered becomes a defect and tends to cause a decrease in adhesion between the overcoat layer and the dielectric layer in a later step. In addition, when an electrode or the like is formed on this overcoat layer, it is likely to cause a disconnection due to a step in the color filter portion when the electrode is formed. The coat layer is preferably formed to have a thickness of 0.1 μm or more to smooth the pattern step.
[0022]
[0023]
DETAILED DESCRIPTION OF THE INVENTION
[0024]
  The form of the color filter in this invention isThe transparent substrate 8, the fixing pattern 4 formed on the transparent substrate 8 at regular intervals, the transparent substrate 8 and the fixing pattern 4,An overcoat layer 3 formed so as to cover from above;And a colored pattern 6 formed on the overcoat layer 3 and formed between the fixed patterns 4, and an overcoat layer 3 formed on the fixed pattern 4 and an overcoat layer 7 formed on the colored pattern 6. This is a heat-resistant color filter.
[0025]
  AndThe form of the color filter in this invention isThe overcoat layer 3 is a heat-resistant color filter having a film thickness of 10 μm or less. This overcoat layer is used when the pattern is fixed by baking.Fixationpattern4Since it is also applied to a portion where no film is formed, it is desired to have high light transmittance. When the film thickness after baking exceeds 10 μm, the transmittance of the heat-resistant color filter at the display color light wavelength Greatly decreases, making it difficult to satisfy the characteristics of the color filter. Since a color filter is formed later in a portion where this pattern is not formed, the film thickness after firing is required to be 10 μm or less in order to ensure the transmittance and pattern smoothness of the color filter.
[0026]
  or,The form of the color filter in this invention isThis is a heat-resistant color filter in which an optical density of a pattern obtained by forming a light-transmitting overcoat layer 3 on a colorant pattern (fixed pattern 4) and firing fixed is 0.3 or more. When the optical density is 0.3 or more, the fire-fixed pattern has a sufficient light-shielding performance, and a heat-resistant color filter that ensures a contrast difference with a desired color filter portion can be formed.
[0027]
  Furthermore,The form of the color filter in this invention isThe heat-resistant color filter is characterized in that the overcoat layer 7 is formed to have a thickness of 0.1 μm or more. Here, when the overcoat layer is formed with a film thickness of 0.1 μm or more, the fixed pattern 4 and the colored pattern 6 are sufficiently covered, the pattern step is smoothed, and defects are less likely to occur. 7 and a color filter that can improve the adhesion between the dielectric layer and the dielectric layer.
[0028]
  The heat resistant color filter of this invention isThe colored photosensitive composition 1 is coated on the transparent substrate 8, exposed, developed, and further baked.Fastening pattern 4After forming thisFastening pattern 4An overcoat layer 3 having optical transparency is formed onFastening pattern 4The fixed pattern 4 was formed by coating and baking.Further of the transparent substrate 8Colored photosensitive composition 5 on topAll overAfter applyingPattern by photomaskexposureShiTo develop,After going for red, blue and green,Furthermore, the colored pattern 6 is formed by firing, and the overcoat layer 3 on the fixing pattern 4 and the overcoat layer 7 having light transmittance are formed on the colored pattern 6 by firing. This is a method for producing a heat-resistant color filter. That is, after the colored photosensitive composition 1 is applied on a transparent substrate and patterned, it is baked and fixed with a light-transmitting overcoat material, thereby forming a color filter with improved adhesion between the pattern and the substrate. Can do. In addition, the colored photosensitive composition can be used regardless of its kind and composition ratio as long as the developability, coatability, film hardness, etc. of the photosensitive resin are suitable for pattern formation.
[0029]
  Furthermore,This inventionThe colored photosensitive composition 1 is coated on a transparent substrate to form a pattern.Fixationpattern4An overcoat layer 3 having optical transparency is formed thereon, and the pattern is fixed by firing. The overcoat material used here is an inorganic material that is stable in high-temperature baking and has a desired light-transmitting property in order to make the pattern firmly fixed by baking at high temperature. As a material, low melting glass or metal alkoxide can be used.
[0030]
  As a method for producing the heat-resistant color filter according to the present invention, first, the colored photosensitive composition 1 is applied on a transparent substrate, and a desired pattern is exposed and developed. Then this formedFixationpattern4And an overcoat layer 3 having light transmittance by firing at a high temperature around the periphery.Fixationpattern4Is fixed by firing. Then, a colored photosensitive composition 5 is applied onto the substrate on which the fixed pattern 4 is formed, and the desired colored pattern 6 is exposed, developed, and developed to form a pattern, and then the fixed pattern 4 and the colored pattern 6 are heated at a high temperature. By baking, the overcoat layer 7 having light transmittance is formed, and by baking these, it is possible to manufacture a color filter having a smooth surface with no step between the color pixels.
[0031]
  Furthermore, in the heat resistant color filter according to the present invention, black, green, blue, and red color pigments are appropriately used. Therefore, when the heat-resistant color filter is formed with an appropriate film thickness, it is applied to display devices such as field emission displays, fluorescent display devices, discharge display panels and color liquid crystal displays, and color filter layers such as solid-state imaging devices. Therefore, it is possible to manufacture a color filter with improved quality such as color purity and contrast without causing a change in color characteristics even when heat treatment is performed at a high temperature.
[0032]
【Example】
  Embodiments of the present invention will be described below in detail with reference to the drawings.
[0033]
<Example 1>
  First, 55% by weight of butyl methacrylate, 20% by weight of methyl methacrylate, 15% by weight of 2-hydroxyethyl methacrylate, and 10% by weight of methyl acrylate were copolymerized using 2- (2-ethoxyethoxy) ethanol as a solvent to obtain an acrylic resin. Was 40% by weight and the solvent was 60% by weight. And using this acrylic resin, the black coloring photosensitive composition 1 was prepared with the following compounding ratios.
[0034]
(Colored photosensitive composition)
  Acrylic resin 8.2% by weight
  Multifunctional oligoester acrylate
    Dipentaerythritol hexaacrylate 4.9% by weight
  Photopolymerization initiator
    Piperonyl trichloromethyl S-triazine 1.0% by weight
  Diluting solvent
    2- (2-Ethoxyethoxy) ethanol 56.4% by weight
  Colored pigment
    Black pigment (Asahi Chemical Industry Co., Ltd.
      : BLACK # 3247) 29.5% by weight
  In order to form a black matrix layer as a light-shielding layer, the colored photosensitive composition 1 was screen-printed on a transparent glass substrate 8 using a stainless steel screen plate having a thickness of 325 mesh and a plate thickness of 80 μm, and left at room temperature for 5 minutes. After the film surface was dried, the film was dried at 70 ° C. for 20 minutes to form a colored photosensitive composition layer. The obtained colored photosensitive composition layer had a thickness of 2.7 μm and a uniform film thickness over the entire surface, and the surface state was smooth. (See Figure 2)
[0035]
  Next, a photomask having a light-shielding film in which a stripe pattern of 200 mm in length and 210 μm in width is repeatedly formed at a pitch of 450 μm is brought into close contact with the colored photosensitive composition layer, and an ultrahigh pressure mercury lamp is used with an exposure amount of 400 mJ / cm 2. Contact exposure was performed. After the exposure, spray development was performed for 90 seconds with an alkali developer at a temperature of 20 ° C. under an ejection pressure of 1 kg / cm 2, and the colored photosensitive composition layer in the unexposed area was removed to expose the glass substrate 8. The substrate after the development treatment was dried and then heated at 230 ° C. for 1 hour to carry out a hardening treatment. The thickness of the patterned colored photosensitive composition layer after hardening was 2.4 μm.
[0036]
  And after heating this glass substrate 1 in the atmospheric condition at the temperature increase rate of 4 degree-C / min and baking for 60 minutes at the temperature of 420 degreeC, it further heats continuously to 580 degreeC and is 30 minutes at the temperature of 580 degreeC. After firing, the substrate is cooled at a rate of temperature decrease of 4 ° C./min, and the organic resin component of the colored photosensitive composition layer is burned and removed to form a pigment.Fixationpattern4It became. (Refer to FIG. 3) After firing this substrate, a low melting point glass paste (LF-01, manufactured by Nippon Electric Glass Co., Ltd.) is used on the transparent glass substrate 8 using a stainless steel screen plate of 325 mesh plate thickness 80 μm. After screen printing and leaving at room temperature for 10 minutes to dry the film surface, printing was repeated once more, and after drying at 90 ° C. for 15 minutes, a low-melting glass paste layer was formed.
[0037]
  This glass substrate was heated in the air atmosphere at a rate of temperature increase of 4 ° C./min as described above, baked for 60 minutes at a temperature of 420 ° C., and then further heated to 580 ° C. for 30 minutes at a temperature of 580 ° C. After firing, the substrate was cooled at a rate of temperature decrease of 4 ° C./min. By baking under these conditions, the low melting point glass became the light-transmitting overcoat layer 3 and was fixed by baking with the low melting point glass in which the pigment component of the black matrix serving as the light shielding layer was melted. (See FIG. 4) The optical density of the formed black matrix was 1.2.
[0038]
  Next, the following red colored photosensitive composition 5 having the same composition as that described above was applied to the substrate on which the black matrix was formed under the same conditions as described above with a film thickness of 4.7 μm (see FIG. 5). A photomask having a light-shielding film in which openings having a width of 450 μm and a pitch pattern of 450 μm were repeatedly formed was in close contact with the following colored photosensitive composition layer, and contact exposure was performed with an ultrahigh pressure mercury lamp at an exposure amount of 300 mJ / cm 2. .
[0039]
(Colored photosensitive composition)
  Acrylic resin 8.2% by weight
  Multifunctional oligoester acrylate
    Dipentaerythritol hexaacrylate 4.9% by weight
  Photopolymerization initiator
    Piperonyl trichloromethyl S-triazine 1.0% by weight
  Diluting solvent
    2- (2-Ethoxyethoxy) ethanol 56.4% by weight
  Colored pigment
    Red pigment (Daiichi Seika Kogyo Co., Ltd.)
      : TRANS OXIDE RED; Fe2O3) 29.5% by weight
  After the exposure, spray development was performed for 60 seconds with an alkali developer at a temperature of 20 ° C. under an ejection pressure of 1 kg / cm 2, and the colored photosensitive composition layer in the unexposed area was removed to expose the glass substrate 8. The substrate after the development treatment was dried and then heated at 230 ° C. for 1 hour to carry out a hardening treatment. The thickness of the patterned colored photosensitive composition layer after hardening was 4.4 μm. (See Figure 6)
[0040]
  In the same manner as in the formation of the red pattern, a green pattern and a blue pattern were formed using blue and green colored photosensitive compositions, and a color filter substrate was produced. (See Figure 7)
[0041]
  Furthermore, after heating the board | substrate produced in this way in air | atmosphere at the temperature increase rate of 4 degree-C / min and baking for 60 minutes at the temperature of 420 degreeC, it further heats continuously to 580 degreeC, and is the temperature of 580 degreeC After baking for 30 minutes, the substrate was cooled at a temperature drop rate of 4 ° C./minute, and the organic resin component and the like of the colored photosensitive composition layer were burned and removed to form a pattern of pigment. And after baking this board | substrate, the low melting point glass paste (Nippon Electric Glass Co., Ltd. LF-01) was screen-printed on the board | substrate produced in this way using the stainless steel screen plate of 325 mesh plate thickness 80 micrometers. After leaving the film surface to dry for 10 minutes at room temperature, printing was repeated once more, and after drying at 90 ° C. for 15 minutes, a low melting point glass paste layer was formed.
[0042]
  The substrate thus prepared was heated in the air atmosphere at a temperature rising rate of 4 ° C./min as described above, baked at a temperature of 420 ° C. for 60 minutes, and then further heated to 580 ° C. After baking for 30 minutes at the temperature, the substrate was cooled at a temperature decrease rate of 4 ° C./min. By firing under this condition, the low melting glass becomes the light-transmitting overcoat layer 7, and the pigment component of the photosensitive coloring composition layer is covered with the molten low melting glass to form a color filter layer. . (See FIG. 8) The pattern shape and the formation position of the color filter accurately reflect the light-shielding film pattern of the photomask, and the spectral transmittance of the color filter showed a desired value. (See Figure 9)
[0043]
<Example 2>
  A black photosensitive coloring composition having the same composition as in Example 1 was prepared, and a pattern was formed under the same conditions as above to form a black matrix pattern with a film thickness of 2.3 μm. After baking, the organic resin component of the colored photosensitive composition layer is burned and removed and consists of a pigmentFixationpattern4Formed. Then, after firing this substrate, a metal alkoxide material (manufactured by Nippon Soda Co., Ltd.) is used to fix the pattern made of pigment on the thus-prepared substrate using a stainless screen plate of 325 mesh plate thickness 80 μm. : Atron NSi-500) was screen printed and allowed to stand at room temperature for 10 minutes to dry the film surface, followed by drying at 90 ° C. for 15 minutes to form a sol film of metal alkoxide material.
[0044]
  The substrate thus prepared was heated in the air atmosphere at a temperature increase rate of 4 ° C./min as described above, baked at a temperature of 420 ° C. for 60 minutes, and then cooled at a temperature decrease rate of 4 ° C./min. By calcination under these conditions, the metal alkoxide sol film was accelerated by dehydration reaction and polycondensation reaction by dealcoholization reaction, and a gelled metal oxide film was formed. By this gelled metal oxide film, a black matrix pattern made of a pigment was baked and fixed on the glass substrate.
[0045]
  Next, the same red colored photosensitive composition as described above is applied to the substrate on which the black matrix is formed in the same manner as described above under the same conditions as described above, and the film is exposed, developed, and heated and hardened. The film thickness was 2.9 μm.
[0046]
  In the same manner as in the formation of the red pattern, a green pattern and a blue pattern were formed using blue and green colored photosensitive compositions, and a color filter substrate was produced.
[0047]
  Further, a low melting point glass paste (LF-01, manufactured by Nippon Electric Glass Co., Ltd.) was screen-printed on the thus-prepared substrate using a stainless steel screen plate of 325 mesh and a plate thickness of 80 μm. A paste layer was formed.
[0048]
  The substrate thus prepared was heated in the air atmosphere at a temperature rising rate of 4 ° C./min as described above, baked at a temperature of 420 ° C. for 60 minutes, and then further heated to 580 ° C. After baking for 30 minutes at the temperature, the substrate was cooled at a temperature decrease rate of 4 ° C./min. By baking under these conditions, the pigment component of the photosensitive coloring composition layer is obtained as a color filter layer covered with molten low-melting glass, and a heat-resistant color filter having a desired spectral transmittance can be obtained. It was. (See Figure 10)
[0049]
【The invention's effect】
  According to the method for producing a heat-resistant color filter of the invention according to claim 1, the colored photosensitive composition is coated on a transparent substrate, exposed, developed, patterned, and then has light transmittance on the pattern. By forming the overcoat layer and baking and fixing the pattern, the adhesion of the formed pattern portion to the substrate can be improved. Thereafter, a colored photosensitive composition is applied onto the fixed pattern, and the desired pattern is exposed and developed to form a desired colored pattern in a portion other than the fixed pattern, and on the formed fixed pattern and the colored pattern. A heat-resistant color filter having an overcoat layer having light transmittance is formed by adhering a black matrix portion fixed by firing and an overcoat layer formed on the black matrix portion, and a color filter portion formed between the black matrices. Since it coat | covers, it becomes possible to improve the adhesiveness of the whole overcoat layer.
[0050]
  Further, according to the method for producing a heat-resistant color filter of the invention according to claim 2, as a material for firing and fixing a pattern in which an overcoat layer having light transmittance is formed on a pattern formed from a colored photosensitive composition. , Low melting point glass, or metal alkoxide is used. These materials used for firing and fixing are stable without burning even when fired at a high temperature, have desired light transmittance, and the pattern is firmly fixed to the substrate, thereby improving the pattern adhesion.
[0051]
  Further, according to the invention according to claim 3, the transparent substrate 8, the fixing pattern 4 formed on the transparent substrate 8 at a constant interval, and the transparent substrate 8 and the over pattern formed on the fixing pattern 4 It has a coating layer 3, a colored pattern 6 formed between the fixed patterns 4, an overcoat layer 3 on the fixed pattern 4, and an overcoat layer 7 formed on the colored pattern 6. A heat resistant color filter can be provided.
[0052]
  Further, according to the invention of claim 4, when the film thickness of the overcoat layer 3 is 10 μm or less, the transmittance of the heat-resistant color filter at the display color light wavelength is sufficient, and the characteristics of the color filter are improved. Fulfill. When the color filter is formed on the electrode substrate on which the pattern has already been formed, the low-melting glass or the metal alkoxide, which is a material for firing and fixing the pattern, has a film thickness after firing of 10 μm or less. It is possible to set the distance between electrodes and the dielectric constant of the dielectric
It becomes easy.
[0053]
  According to the invention of claim 5, the colored photosensitive composition applied and patterned on a transparent substrate is formed using a colorant mainly composed of black, and the colorant pattern is formed on the colorant pattern. Since the optical density of the pattern that is coated, baked and fixed by forming an overcoat layer having light transmittance is 0.3 or more, the light shielding performance of the pattern is sufficient, and the contrast difference from the colored pattern is sufficiently large It can be ensured, and the characteristics of the color filter can be improved.
[0054]
  Further, according to the invention of claim 6, since the overcoat layer 7 is formed to have a thickness of 0.1 μm or more, the overcoat layer having light transmittance is sufficiently covered on the fixed pattern and the colored pattern, resulting in a defect. It becomes possible to suppress generation | occurrence | production of a part.
[0055]
[Brief description of the drawings]
FIG. 1 is a patterned pigment and an optically transparent overcoat.
        The schematic sectional drawing of the conventional color filter which provided the coating layer and planarized.
FIG. 2 shows a color photosensitive composition for a color filter according to Example 1, which was applied and dried.
    A cross-sectional view of the subsequent state is shown.
FIG. 3 shows a color filter according to Example 1 after firing a black matrix pattern.
        FIG.
FIG. 4 is a cross-sectional view after firing and fixing a black matrix pattern according to Example 1;
5 is a cross-sectional view after coating a colored photosensitive composition for forming a colored pattern according to Example 1. FIG.
    Plan view.
6 is a cross-sectional view after forming a color pattern of one color according to Embodiment 1. FIG.
7 is a cross-sectional view after forming a coloring pattern of three colors (R, G, B) according to Embodiment 1. FIG.
8 is a cross-sectional view of a heat-resistant color filter according to Example 1. FIG.
9 is a spectral transmittance curve of a heat-resistant color filter manufactured according to Example 1. FIG.
10 is a spectral transmittance curve of a heat-resistant color filter produced according to Example 2. FIG.
[Explanation of symbols]
1 Colored photosensitive composition
2 ... Black matrix pattern
3 ... Overcoat layer
4 ... Fixed pattern
5 ... Colored photosensitive composition
6. Coloring pattern
7 ... Overcoat layer
8 ... Glass substrate
9 Color filter
10 ... Low melting point glass

Claims (5)

After the colored photosensitive composition 1 is applied on the transparent substrate 8, exposed, developed, and further baked to form the fixed pattern 4 ,
After forming an overcoat layer 3 having optical transparency and covers the fastening pattern 4 on the fastening pattern 4, and fired secured,
This further colored photosensitive composition on 5 of the overcoat layer 3 on the fastening pattern 4 to pattern exposure by the photomask after applied to the entire surface, to be developed, after red, blue, each green, further Forms a colored pattern 6 by firing,
A method for producing a heat-resistant color filter, wherein the overcoat layer 3 on the fixed pattern 4 and the overcoat layer 7 having light transmittance are formed on the colored pattern 6 by firing. The method for producing a heat-resistant color filter according to claim 1, wherein a low melting point glass or a metal alkoxide is used as a material for baking and fixing the fixing pattern 4 as the light-transmitting overcoat layer 3. Method for producing a color filter. 2. The method for producing a heat resistant color filter according to claim 1, wherein the overcoat layer 3 has a thickness of 10 [mu] m or less. 2. The method for producing a heat-resistant color filter according to claim 1, wherein an optical density of a portion composed of the fixing pattern 4 and the overcoat layer 3 is 0.3 or more. . 2. The method for producing a heat resistant color filter according to claim 1, wherein the overcoat layer 7 is formed in a thickness of 0.1 [mu] m or more.

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