KR100990601B1 - Color filters and method of manufacturing the color filters - Google Patents

Abstract

The present invention relates to a method for manufacturing a color filter and a color filter manufactured by the method. Specifically, the method for manufacturing the color filter includes the steps of: (a) forming a light shielding part pattern on a substrate; (b) coating a water-soluble polymer solution on the substrate on which the light shielding portion pattern is formed; (c) thermosetting the light blocking part pattern; (d) cleaning the water-soluble polymer layer formed by step (c); And (e) filling ink into the pixel portion partitioned by the light blocking portion pattern.

Color filter, inkjet, pixel part, light shielding part, water soluble polymer

Description

Color filter and manufacturing method of color filter {COLOR FILTERS AND METHOD OF MANUFACTURING THE COLOR FILTERS}

1 is a schematic diagram of a process for producing a color filter using a conventional method.

2 is a schematic diagram of a process for producing a color filter using the method of the present invention.

3 is a photograph of a charge-coupled device (CCD) camera (× 50) in which ink is not filled in the pixel portion.

4 is a photograph of a CCD camera (× 50) in which ink is uniformly filled in the pixel portion.

The present invention relates to a method for producing a color filter and a color filter produced by the method. More specifically, a method of manufacturing a color filter which can reduce costs by simplifying the process of manufacturing a color filter by inkjet by maintaining the inking property of the pixel portion without a process of forming a separate ink layer and without complicated surface treatment. And it relates to a color filter produced thereby.

In general, micropatterns used in display devices such as semiconductor circuit devices and LCDs are formed by photolithography using photoresist. 1 shows a photolithography process showing the steps of coating, exposure, development, cleaning and curing. However, although photolithography has the advantage of obtaining precisely the desired pattern, it has to go through many steps and many kinds of materials are used to maximize the effect of photoresist, coating, etc. There is a disadvantage that a large amount of photoresist is consumed in the process of. Recently, in order to overcome such disadvantages of photolithography, a technique of obtaining a fine pattern by an inkjet printing method has been proposed.

Production of color filters by inkjet printing is possible by forming a black matrix (BM), which is a light shielding part, by using a conventional photolithography method, and spraying R, G, and B ink on the pixel portion between the BMs using the BM as a partition wall. Lose. At this time, if the BM used as the partition does not have ink repellency against the ink, the ink sprayed on the pixel portion between the BMs flows over the BM partition wall into the adjacent pixel portion, and there is a possibility of mixing of the same or different colors. have. Therefore, the BM material, which serves as a partition in inkjet printing, must have a considerably high ink repellency for ink.

On the contrary, the substrate surface of the pixel portion between BMs must have low ink repellency for the ink so that the ejected ink can spread evenly within the pixel portion, eliminating light leakage caused by unfilled pixel portion, and reducing the level difference between the pixel portion or the pixel. have. However, in general, when the BM pattern is formed using a BM material having strong ink repellency, the glass substrate surface of the pixel portion between the BMs is similar to the surface of the BM having ink repellency by a post-baking process. The surface is modified to have ink repellency of the ink, and thus, even though ink is jetted, the surface does not spread well within the pixel portion, so that unfilling occurs, and a step in the pixel portion or between the pixel portions is severely generated. 3 illustrates a state in which the ink is not filled in the pixel portion.

In order to solve this problem, Japanese Patent Laid-Open No. 1997-203803 discloses a method of surface-treating main parts with a pro-ink treatment agent and surface treatment of convex portions with a repellent ink treatment agent. However, this method has a problem in that the ink repellent treatment portion is not affected while the ink repellent agent is treated, or two separate treatments, the ink repellent ink and the ink repellent ink treatment, are performed.

As another method, Korean Patent Laid-Open Publication No. 2000-0047958 proposes a color filter having a wettability variable layer that can change wettability. However, this method has a disadvantage in that the manufacturing process is complicated by forming a separate layer called a wettability variable layer in addition to the barrier layer and the ink layer.

In Japanese Patent Laid-Open No. 2000-258622, a method of pattern exposing a photosensitive layer to change an exposed portion into a hydrophilic region is introduced. However, this method also requires an additional process of forming a separate photosensitive layer.

Accordingly, an object of the present invention is to improve the spreadability of the ink in the pixel portion by maintaining the hydrophilicity of the pixel portion between the light shielding portion while maintaining the ink repellency of the light blocking portion serving as a partition wall in manufacturing the color filter by the inkjet method There is provided a method for producing a color filter in the pixel portion or between the pixel portion, no color dropping due to unfilled, uniform surface and small step between the pixel portion or the pixel portion, and the color filter manufactured by the method. It is.

The present invention,

(a) forming a light shielding pattern on the substrate;

(b) coating a water-soluble polymer solution on the substrate on which the light shielding portion pattern is formed;

(c) thermosetting the light blocking part pattern;

(d) cleaning the water-soluble polymer layer formed by step (b); And

(e) filling ink into a pixel portion partitioned by the light blocking portion pattern

It provides a method of manufacturing a color filter comprising a.

The present invention provides a color filter manufactured by the above method.

The present invention provides a display device including the color filter.

Hereinafter, the present invention will be described in detail.

The method for manufacturing a color filter according to the present invention comprises the steps of (a) forming a light shielding part pattern on a substrate, (b) coating a water-soluble polymer solution on a substrate having the light shielding part pattern formed by the step (a), ( c) thermosetting the light blocking portion pattern, (d) washing the water-soluble polymer layer formed by the step (b), and (e) filling ink into the pixel portion partitioned by the light blocking portion pattern. Steps.

Specifically, in the case of forming the light-shielding part pattern serving as a partition wall when applying the inkjet method by a conventional photolithography process, an ink repellent material is coated on a substrate, and a pre-baking, UV exposure, developing and post-baking process is performed. Will go through. In particular, while the post-baking process of curing the light-shielding material by a high temperature heat treatment, the ink-repelling component of the light-shielding portion affects the pixel portion, thereby changing the pixel portion to maintain ink-repellency. Occurs. This phenomenon is presumed to be because the ink-repellent material of the light shielding part pattern is adsorbed and remains at the pixel unit located in the process of volatilization at high speed during high temperature heat treatment during manufacturing of the light shielding part pattern. In addition, when no post-baking is performed and no processing is performed after development, there is a problem in that the shape of the light blocking portion pattern is deformed while the uncured component of the light blocking portion pattern is dissolved in the ink solvent by the ejected ink.

However, in the present invention, the water-soluble polymer solution is coated on the substrate on which the light-shielding portion pattern is formed in order to prevent ink repelling of the pixel portion before the post-baking treatment of the light-shielding portion pattern. The coating of the water-soluble polymer solution may prevent the volatiles generated during the post-baking process from adsorbing to the pixel portion, thereby preventing the ink-repellent material of the light blocking portion pattern from affecting the pixel portion during the curing process and remaining as an adsorbent material. . As a result, the hydrophilicity of the pixel portion can be maintained and ink can be uniformly filled without slipping. The state in which the ink is uniformly filled in the pixel portion is as shown in the photograph of FIG. 4.

Step (a) is a process of forming a light blocking pattern on the substrate. The step (a) may comprise: (a1) applying a light shielding material on the substrate; (a2) prebaking the light blocking material; And (a3) selectively exposing and developing the prebaked light blocking material.

Although it does not specifically limit as a material as a said board | substrate, A glass substrate, a plastic substrate, another flexible substrate, etc. can be used, A transparent glass substrate with strong heat resistance is preferable.

In the step (a1), the method of applying the light shielding material on the substrate may be performed by a method known in the art, such as spin coating, dip coating, or doctor blading.

Preferably, the light blocking portion material has ink repellency, and the light blocking portion material may contain 0.01 to 0.3 wt.% Of the total composition for forming a light shielding portion using a silicone-based or fluorine-based surfactant which is an ink repellent component in order to have ink repellency. It is desirable to contain

As the light-shielding coloring material of the light-shielding part material, a hybrid color material in which carbon black, an organic pigment mixed light-shielding colorant, and carbon black and an organic pigment mixed light-shielding colorant are mixed is used in 20 to 50 of the total solids of the composition for forming the light-shielding part. It is preferable to contain by weight%.

The light shielding part composition may include a solvent for coating property.

In the step (a2), the prebaking is preferably performed at 50 to 150 ° C. for 10 to 1000 seconds.

Selective exposure and development in the step (a3) can be carried out using a method known in the art. For example, the prebaked light shielding material may be selectively exposed using a photomask, followed by developing the exposed or unexposed portions.

The thickness of the light blocking part pattern manufactured in step (a) is preferably 1.1 to 5 μm, and the optical density is preferably 3 to 6 in the thickness range. In addition, the light shielding portion pattern preferably has a contact angle of 20 to 60 ° with respect to the ink.

The water-soluble polymer in the water-soluble polymer solution of step (b) can be largely divided into natural polymers and natural polymer derivatives and synthetic polymers, and the cations such as alginate and pectin in the natural and natural polymer derivatives. Cationic or anionic polysaccharide derivatives and substituents prepared using poly or anionic polysaccharides and polysaccharides such as cellulose, starch, chitin and chitosan, nucleic acids, teichoic acid, carrageenan and agar. ), Gum arab, gelatin or lignosulfonic acids. Synthetic polymers include nonionic water-soluble polymers as poly (ethylene oxide), poly (propylene oxide), polyoxymethylene, poly (trimethylene oxide) (poly ( trimethylene oxide) and poly (tetramethylene oxide) and the like and copolymers thereof, and polyethers such as poly (vinyl methyl ether) and poly ( Poly (ethylene imine), poly (acrylic acid), polyacrylamide, poly (methacrylic acid), polymethacrylamide ), Poly (N, N-dimethylacrylamide), poly (N-isopropylacrylamide), N-poly (N-acrylylglycine) Amides) ((N-poly (N-acrylylglycinamide)) and poly (N-methacrylylglycinamide) (poly ( Acrylic polymer such as N-methacrylylglycinamide) and copolymers thereof, poly (vinyl alcohol), poly (vinyl acetate), polyvinylpi Vinyl polymers such as polyvinylpyrrolidone, polyvinyloxazolidone, polyvinylmethyloxazolidone, etc. Ionic water-soluble polymers include poly (acrylic). acid)), poly (ethylene imine), poly (ethylene sulfonic acid), poly (methacrylic acid), poly (phosphoric acid) (poly (phosphoric acid)), poly (silicic acid), poly (styrenesulfonic acid), polyvinylamine, poly (2-vinylpyridine) salts of (poly (2-vinylpyridine)), poly (4-vinylpyridine), poly (vinyl sulfuric acid) salt and poly (diallyldimethylammonium chloride), poly ([dimethylimino] trimethylene (dimethylimino) -hexamethylenedibromide)) (poly ([(dimethylimino) trimethylene ( dimethylimino) -hexamethylene dibromide])), poly (ethylenephosphonic acid), poly (maleic acid), poly (2-methacryloyloxyethane-1- Sulfonic acid) (poly (2-methacryloyloxyethane-1-sulfonic acid)), poly (3-methacryloyloxypropane-1-sulphonic acid) (poly (3-methacryloyloxypropane-1-sulfonic acid)), poly (4 Poly (4-vinylbenzoic acid), poly4-vinyl (benzyltrimethylammonium salts), poly [3- (vinyloxy) propane-1-sulfonic acid] (poly [3- (vinyloxy) propane-1-sulfonic acid]), poly (4-vinylphenol), poly (4-vinylphenyl sulfuric acid) , Poly (2-vinylpiperidine), poly (4-vinylpiperidine) and poly (N-vinylsuccinamidic acid), and the like, and also from ionic and nonionic monomers or polymers. The copolymer obtained can be included. However, the scope of the present invention is not limited only to the examples described above, and one or more compounds selected from the group may be used. Preferably, the water-soluble polymer solution is coated, and water may be used as the solvent, but is not limited thereto. The water-soluble polymer is preferably used 1 to 20% by weight based on the total weight of the water-soluble polymer solution.

In addition, in order to improve the coating property on the light-shielding portion pattern of the water-soluble polymer solution, additives such as a surfactant used in an aqueous solution may be used in an amount of 0.01 to 0.3% by weight based on the total weight of the water-soluble polymer solution.

The water soluble polymer solution of the present invention can be coated by methods known in the art. Specifically, it may be coated with a bar coder, a spin coater or a slit coater, and may be preferably coated using a slit coater. When the coated water-soluble polymer solution is coated on the substrate on which the ink repellent light shielding pattern is formed, it is not particularly limited, but is preferably coated with a thickness of 1 to 5 μm. At this time, the coated water-soluble polymer solution may be coated on both the light blocking portion pattern and the pixel portion according to the coating thickness, but due to the ink repellency of the light blocking portion pattern, the water soluble polymer solution is only filled in the pixel portion without remaining on the light blocking portion pattern.

Step (c) is a step of thermosetting the light shielding pattern, and post-baking the substrate having the ink repellent light shielding pattern coated with the water-soluble polymer solution at 200 to 250 ° C. for 10 to 200 minutes. By the post-baking, the surface of the light blocking portion pattern maintains ink repellency while the pixel portion between the light blocking portion patterns is formed with a water-soluble polymer layer of a thin film.

In the step (d), the water-soluble polymer layer formed by the step (b) may be washed, and the water-soluble polymer layer of the thin film may be washed with a developer or water. Accordingly, the pixel portion filled with the water-soluble polymer layer while maintaining the ink repellency of the surface of the light blocking portion pattern can manufacture a light blocking portion substrate having hydrophilicity.

In the step (e), the ink is filled in the pixel portion partitioned by the light blocking portion pattern, and two or more kinds of inks, for example, three kinds of inks, such as R, G, and B, may be simultaneously or continuously filled. The ink may use a photocurable or thermosetting ink. The ink filling is preferably performed by an inkjet method.

When each ink is discharged to the pixel portion by the inkjet method, the light-shielding portion pattern formed according to the method of the present invention has ink repellency and the pixel portion has an ink repellency, so that the ejected ink spreads uniformly in the pixel portion. It may be applied convexly higher than the light shielding pattern.

Since the ink discharged in this process does not cross the ink repellent shading pattern, three ink can be continuously discharged without a separate post-treatment process for each ink. Photocuring or thermosetting may be performed.

In the case of the photocurable ink, pre-bake is carried out for 10 to 2000 seconds at a temperature of 50 to 150 ° C after each ink discharge or after all ink discharges, and exposure is performed at an exposure dose of 40 to 300 mJ / cm ² . After the high temperature thermal curing may be carried out for 10 to 200 minutes at a temperature of 200 to 250 ℃. In the case of the thermosetting ink, after pre-bake for 10 to 2000 seconds at 50 to 150 ° C. after each ink discharge or after all ink discharges, the temperature is 200 to 250 ° C. without a separate exposure process. High temperature heat curing may be performed for 10 to 200 minutes, and the above process may be performed with respect to an ink mixed with a thermosetting type and a photo curing type.

The present invention provides a color filter manufactured by the above method.

The color filter manufactured as described above maintains the inking properties of the pixel portion without the process of forming a separate inking layer and without complicated surface treatment, so that no color mixture, color dropout, unfilled, uneven color and uniform surface are filled during ink filling. It is manufacturable and can reduce costs by simplifying the process.

The present invention provides a display device including the color filter.

The display device according to the present invention may have a configuration known in the art, except for including the color filter according to the present invention described above.

Example  One

Copolymer of benzyl (meth) acrylate / (meth) acrylic acid (acid value 110 KOH mg / g, molar ratio 70/30, Mw = 65 parts by weight of carbon black as colorant and alkali-soluble resin binder with respect to 1000 parts by weight of photosensitive resin composition) 30,000) 29 parts by weight, and 70 parts by weight of a polymer having an allylglycidyl ether added to the copolymer of benzyl (meth) acrylate / (meth) acrylic acid (acid value 80 KOH mg / g, Mw = 22,000), a functional monomer Rhodipentaerythritol hexaacrylate 50 parts by weight, 20 parts by weight of 2-benzyl-2- (dimethylamino) -1- (4-morpholinophenyl) butyl-1-one as a photopolymerization initiator, 2,2'- 10 parts by weight of bis (o-chlorophenyl) -4,4,5,5'-tetraphenyl-1,2'-biimidazole, 5 parts by weight of 4,4-bis (diethylamino) benzophenone, and mer 5 parts by weight of captobenzothiazole, 9 parts by weight of a polyester-based dispersant as a dispersant, and 1 part by weight of a fluorine-based surfactant as a leveling agent for imparting ink repellency, solvent 440 parts by weight of propylene glycol monomethyl ether acetate and 290 parts by weight of ethoxyethyl propionate were mixed. Then, the mixture was stirred for 5 hours to prepare a black matrix photosensitive resin composition.

The water-soluble polymer solution was prepared by mixing 10 parts by weight of polymethacrylic acid sodium salt (Aldrich, Mn = 4,000, Mw = 6,500) with 990 parts by weight of secondary distilled water based on 1000 parts by weight of the water-soluble polymer solution. It was.

The photosensitive resin composition solution prepared as described above was spin coated onto glass and subjected to an electrothermal treatment at about 100 ° C. for 2 minutes to form a coating film having a thickness of about 2.4 μm. Then, after cooling at room temperature, it was exposed with an energy of 100 mJ / cm 2 under a high pressure mercury lamp using a photomask. The exposed substrate was developed by spraying in a 0.04% aqueous KOH solution at a temperature of 25 ° C., washed with pure water and dried by air blowing. The water-soluble polymer solution was uniformly applied to a thickness of 2.0 μm using a slit coater on the glass substrate on which the light-shielding pattern was formed, and then post-baked in a convection oven at 220 ° C. for 30 minutes.

In the coating film obtained as described above, the coating film thickness of the light-shielding pattern was 2.0 μm, and the optical density was 4.3, which showed excellent light blocking property, and the thickness of the water-soluble polymer layer formed in the pixel portion was 0.2 μm.

In the coating film obtained as described above, the water-soluble polymer layer formed in the pixel portion was cleaned by spray using pure water at a temperature of 25 ° C., and dried by air blowing.

The red ink ejected to each pixel part by the inkjet method was 43 parts by weight of Pigment Red # 254, 13 parts by weight of Pigment Red # 177, 9 parts by weight of Pigment Yellow # 139 with a colorant based on 1000 parts by weight of the ink composition. 38 parts by weight of a polymer having allylglycidyl ether added (Mw = 24,000) to a copolymer in which benzyl (meth) acrylate and (meth) acrylic acid were formed in a molar ratio of 70:30 using a soluble resin binder, and dipenta as a functional monomer. 75 parts by weight of erythritol hexaacrylate, 5 parts by weight of azoamide-based thermal polymerization initiator, 23 parts by weight of polyester-based dispersant as a dispersant, 0.4 part by weight of fluorine-based surfactant as a leveling agent, 650 parts by weight of butyl carbitol acetate as a solvent 63 parts by weight of propylene glycol monomethyl ether acetate, 60 parts by weight of methoxy propanol, and 15 parts by weight of butyl cellosolve acetate were mixed. Was prepared in the ink-jet ink composition was stirred for 5 hours.

The red ink prepared as described above was ejected by the inkjet method to the pixel portion having ink repellency and improved spreadability of the ink. In this case, 35 to 40 drops were appropriate for the amount of ejected ink or the number of droplets required for uniformly obtaining a desired color without the phenomenon of unfilled or discolored color in each pixel portion.

4 shows that the ink is uniformly filled after all the processes are completed.

Comparative example  One

The same procedure as in Example was conducted except that the coating and washing step of the water-soluble polymer was not performed.

As shown in FIG. 3, the ink did not spread and aggregated to uniformly fill the entire pixel portion.

In the present invention, in manufacturing a color filter by an inkjet printing method, while maintaining ink repellency of the light blocking portion serving as a partition wall while maintaining the hydrophilicity of the pixel portion between the light blocking portion pattern to improve the spreadability of the ink in the pixel portion It is possible to manufacture a color filter in which there is no color mixing in the pixel portion or between pixel portions, no color dropping due to unfilling, and the surface is uniform and the level difference between the pixel portion and the pixel portion is small.

Claims (11)

(a) forming a light shielding pattern on the substrate; (b) coating a water-soluble polymer solution on the substrate on which the light shielding portion pattern is formed; (c) thermosetting the light blocking part pattern; (d) washing the water-soluble polymer formed by step (b); And (e) filling ink into a pixel portion partitioned by the light blocking portion pattern Method of manufacturing a color filter comprising a. The method of claim 1, wherein the light blocking part pattern has an optical density of 3 to 6 at a thickness of 1.1 to 5 μm, and a contact angle with respect to the ink of the light blocking part pattern is 20 to 60 °. The light shielding material according to claim 1, wherein the light shielding part material comprises a silicone-based or fluorine-based surfactant in an amount of 0.01 to 0.3% by weight in the total composition for forming the light shielding part. A method for producing a color filter comprising 20 to 50% by weight of the total solid content of the composition for forming a light shielding portion of a hybrid type of colorant, a carbon black and an organic pigment mixed light-shielding colorant. The method according to claim 1, wherein the water-soluble polymer in the water-soluble polymer solution is cationic or anionic polysaccharides and cationic or anionic polysaccharide derivatives and substituents, nucleic acids, tycoic acid, carrageenan, agar, gum Arab, gelatin, lignosulfonic acid, A color filter comprising at least one compound selected from the group consisting of nonionic water-soluble synthetic polymers and copolymers thereof, ionic synthetic polymers and copolymers thereof, and copolymers obtained from ionic and nonionic monomers or polymers. Manufacturing method. The method according to claim 1, wherein the water-soluble polymer is 1 to 20% by weight based on the total weight of the water-soluble polymer solution. The method of claim 1, wherein the thickness of the coating layer of the water-soluble polymer solution coated by the step (b) is 1 to 5 ㎛. The method of claim 1, wherein step (e) is to fill two or more kinds of inks simultaneously or sequentially. The method of claim 1, wherein the ink filling in the step (e) is performed by an inkjet method. The method of claim 1, wherein the ink is a photocurable or thermosetting ink. The color filter manufactured by the method of any one of Claims 1-9. A display device comprising the color filter of claim 10.

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