KR100938446B1 - Green pigment composition for color filter - Google Patents

Abstract

The present invention relates to a green pigment composition for color filters, specifically (A) 1 pigment; (B) binder resin; (C) dispersants; (D) A solvent and (E) The metal oxide which has an average particle diameter of 10-50% with respect to the average particle diameter (D50) of the said pigment is included.

The green pigment composition for a color filter of the present invention is excellent in dispersion stability and high light transmittance even when the pigment is used at a high concentration, and thus a color filter having high luminance can be provided.

 Color filter, pigment, metal oxide, brightness, green

Description

Green pigment composition for color filters {GREEN PIGMENT COMPOSITION FOR COLOR FILTER}

The present invention relates to a green pigment composition for a color filter, and more particularly, to a green pigment composition used for manufacturing a color filter of a green portion used in a liquid crystal display and a color filter using the same.

Liquid crystal display devices are being developed into portable notebooks, mobile phones, TVs, etc. on the basis of their thinness and excellent space saving and low power consumption.

In order to raise the liquid crystal display television to the color reproduction range (about 70%) as in the conventional cathode ray tube television, the color of each pixel of the color filter must be made darker. Here, the color reproduction range is defined as the area ratio of triangles connecting the red, green, and blue color coordinates in the Yxy color system.

As such, the concentration of the pigment used as the colorant must be increased to increase the color of the pixel, and thus, there is a disadvantage in that the dispersion of the pigment particles occurs and the dispersion stability is lowered. Therefore, in order to increase dispersion stability, the pigment is refined by using a large amount of dispersant and a binder when preparing the pigment dispersion. However, in this case, a problem occurs that the pattern is not formed well when the pixel is formed, and the light transmittance is low to make the image dark.

Therefore, Japanese Patent Laid-Open Publication No. 2005-316244 discloses a method for solving such a problem by treating a surface of a green pigment with a sulfonic acid derivative and a salt thereof to improve dispersion stability. However, this method has a problem in that the yield is reduced in the manufacturing process, environmental pollution due to a large amount of acid generated during the surface treatment. Alternatively, Korean Patent Publication No. 2007-056052 discloses a method of preparing a pigment dispersion having excellent dispersion stability by treating a pigment surface with a carbodiimide compound. However, this method has a disadvantage in that the purification is difficult after the surface treatment and the yield is low. As another method, Japanese Patent Laid-Open No. 11-080578 describes the preparation of a green pigment dispersion for color filters by adding an acetate compound, but with this method, the luminance of the pixel coating film when the color filter is manufactured. There are problems such as falling.

An object of the present invention is to use a metal oxide having an average particle diameter of 10 to 50% relative to the average particle diameter of the pigment, thereby reducing the content of the dispersant during pigment dispersion to increase the light transmittance and to form a fine pattern pigment for color filters To prepare a dispersion.

Further, another object of the present invention is to provide a green pigment composition having excellent dispersion stability.

Technical problems to be achieved by the present invention are not limited to the technical problems mentioned above, and other technical problems not mentioned will be clearly understood by those skilled in the art from the following description.

A first embodiment of the present invention for achieving the above object is (A) pigment; (B) binder resin; (C) dispersants; (D) a metal oxide having an average particle diameter of 10 to 50% with respect to the average particle diameter (D50) of the pigment; And (E) to provide a green pigment composition for a color filter comprising a solvent.

The pigment may be selected from the group consisting of triphenylmethane (Triphenylmethane), thiazole (Thiazole), phthalocyanine (Phthalocyanine), violanthrone (Violanthrone) and combinations thereof; Anthraquinone, Azo, Isoindolinone, Quinoline, Quinophthalone, and combinations thereof may be used. In addition, after the micronization of the pigment by the mechanization treatment with the pigment, any one can be used as long as x is in the range of 0.27 to 0.33 when y is 0.60 based on the Yxy color system.

The metal oxide is preferably nanoparticles having a white particle size of 10 to 50% with respect to the average particle diameter (D50) of the pigment, and among them, silicon oxide, titanium oxide, zinc oxide, magnesium oxide. And it can use preferably selected from the group which consists of these combinations.

In addition, the metal oxide in the present invention is 10m ² / g It is preferred to have a specific surface area of from 100 m ² / g.

Other specific details of embodiments of the present invention are included in the following detailed description.

The green pigment composition for a color filter of the present invention is excellent in dispersion stability and high light transmittance even when the pigment is used at a high concentration, and thus a color filter having high luminance can be provided.

Hereinafter, embodiments of the present invention will be described in detail. However, this is presented as an example, by which the present invention is not limited and the present invention is defined only by the scope of the claims to be described later.

The present invention provides a green pigment composition for a color filter, in particular, by using a nano-sized metal oxide as a dispersion stabilizer, a green pigment that can increase the light transmittance and form a fine pattern by reducing the content of the dispersant during pigment dispersion It relates to a composition.

Accordingly, the first embodiment of the present invention is (A) pigment; (B) binder resin; (C) dispersants; (D) a solvent; And (E) to provide a green pigment composition for a color filter comprising a metal oxide having an average particle diameter of 10 to 50% with respect to the average particle diameter of the pigment.

Hereinafter, each component will be described in detail.

(A) pigment

In the present invention, the pigment is triphenylmethane (Triphenylmethane), Thiazole (Thiazole), Phthalocyanine (Phthalocyanine), Violanthrone (Violanthrone) and a green pigment selected from the group consisting of a combination thereof; An yellow pigment selected from the group consisting of anthraquinone, Azo, isoindolinone, quinoline, quinophthalone, and combinations thereof ; And it can be used selected from the group consisting of a combination thereof. In addition, after the micronization of the pigment by the mechanization treatment with the pigment, any one can be used as long as x is in the range of 0.27 to 0.33 when y is 0.60 based on the Yxy color system.

It is preferable that the average particle diameter (D50) of the said pigment is 30-100 nanometers . When the average particle diameter (D50) of the pigment is in the range of 30 to 100nm, after forming the pixel, it is preferable because appropriate durability such as heat resistance, chemical resistance, adhesion, etc. can be obtained, and excellent luminance can be obtained.

The particle size of the pigment may be controlled by mechanical or chemical methods. It is of course also possible to use ones commercially available in the desired particle size. The mechanical method can be carried out using machines such as bead mills, ball mills, ultrasonic mills, sand mills, jet mills, paintsakers and the like.

The chemical method mixes the pigment, the water-soluble inorganic salt and the humectant, Acid pasting to obtain fine particles by kneading the compound in a high pressure kneader to reduce the size of the pigment to less than 50 nanometers, or dissolving it in an acid such as sulfuric acid and depositing it in a poor solvent. Method can be used. The water-soluble inorganic salts and wetting agents may be used in any chemical method for controlling the size without degrading the properties of the pigment.

Of course, any method can be used as long as the size of the pigment particles can be adjusted in addition to the above method.

(B) binder resin

As the binder resin used in the present invention, a polymer having at least one acidic group can be preferably used. A carboxyl group, a sulfonic acid group, or a phosphoric acid group is mentioned as said acidic group. Examples of the binder resin include allyl methacrylate, aminopropyl acrylate, cyclohexyl acrylate, phenoxy acrylate, methoxyethyl acrylate, methoxydiethylene glycol acrylate, methoxy propylene acrylate, acrylonitrile, Polyhydroxy selected from the group consisting of hydroxyethyl methacrylate, ethyl methacrylate, benzyl methacrylate, ethylhexyl methacrylate, glycerol methacrylate, methyl methacrylic acid, methacrylic acid, copolymers thereof, and combinations thereof An acrylate resin is mentioned. Preferably, an acrylic copolymer having at least one acidic group such as a carboxyl group is preferable, and these may be used alone or in combination of two or more, but are not particularly limited thereto.

It is preferable that the binder resin has a weight average molecular weight of 5,000 to 40,000. When the weight average molecular weight of the binder resin is included in the above range, the dispersion occurs well, and the appropriate viscosity can be maintained, so that the dispersion can occur effectively.

In addition, the binder resin is preferably used in an amount of 1 to 50 parts by weight based on 100 parts by weight of the pigment. When the binder resin content is included in the above range, while the dispersion occurs effectively, it is possible to maintain the appropriate viscosity, thereby maintaining the optical, physical, chemical quality during product application.

(C) dispersant

Representative examples of the dispersant used in the present invention include polycarboxylic acid esters, unsaturated polyamides, polycarboxylic acids, polycarboxylic acid alkyl amine salts, polyacrylic dispersants, polyethyleneimine dispersants, polyurethane dispersants, and the like. It can be used individually or in mixture of 2 or more types. Specific examples of the dispersant include KP series of Shin-Etsu Chemical Co., Ltd., polyflow series of Kyoeisa Co., Ltd., Dispervic series of BK Co., Ltd., Solsper Series of Nuburizol, EFKA Dispersant series of Efka Corporation, and Adispa of Ajinomoto Co., Ltd. Series.

The dispersant is preferably used in an amount of 10 to 80 parts by weight with respect to 100 parts by weight of the pigment, and when the content of the dispersant is included in the above range, dispersion is effectively performed and preferable viscosity can be maintained for smooth dispersion.

(D) metal oxide

As the metal oxide, it is preferable to use a nano-sized metal oxide having an average particle diameter of 10 to 50% with respect to the average particle diameter of the pigment. In this case, nano size means several nanometers to several hundred nanometers.

The metal oxide acts as a dispersion stabilizer, and it is preferable to use a metal oxide that exhibits white color to maintain color coordinates. Particularly, the metal oxide is selected from the group consisting of silicon oxide, titanium oxide, zinc oxide, magnesium oxide, and combinations thereof. It is better to use the one chosen. By using the metal oxide, it is possible to increase the adsorption of the dispersant on the surface of the pigment particles to relatively reduce the aggregation between the pigment particles to reduce the increase in viscosity.

In addition, the metal oxide may be used by controlling the size in the same manner as described in the pigment , or may be used by controlling the size by sol-gel synthesis using a precursor.

Any method may be used as long as the size of the metal oxide used in the present invention can be adjusted to have an average particle diameter of 10 to 50% relative to the average particle diameter of the pigment.

When the size of the metal oxide is included in the above range, it is preferable to control the cohesion of the metal oxides, it is preferable because it can maintain the appropriate contrast ratio because it does not cause light scattering after manufacturing with a color filter.

It may also be used by treating the surface with fatty acids in order to increase the dispersibility of the metal oxide itself. At this time, the fatty acid used has a carbon number of 12 or more, and specifically, lauric acid, stearic acid, oleic acid, tannic acid, or the like is preferably used . When the surface treatment with the fatty acid, it is preferable because the solvent and the steric effect to the solvent is excellent.

In addition, the metal oxide in the present invention is 10 It is preferred to have a specific surface area of from 100 m ² / g. If the specific surface area of a metal oxide is contained in the said range, it is preferable because adsorption with pigment particle | grains is smooth and a viscosity suitable for storage can be maintained.

In the present invention, the metal oxide is preferably used in an amount of 0.1 to 20 parts by weight with respect to 100 parts by weight of the pigment, more preferably 0.3 to 10 parts by weight. When the content of the metal oxide is included in the above range, the viscosity does not increase even after dispersion, so that dispersion stability can be maintained, and appropriate luminance can be maintained.

(E) solvent

There is no restriction | limiting in particular in the solvent contained in the pigment composition of this invention, It can use individually or in mixture of 2 or more types as needed from a well-known thing. Alcohols such as methanol and ethanol; Ethers such as dichloroethyl ether, n-butyl ether, diisoamyl ether, methylphenyl ether and tetrahydrofuran; Glycol ethers such as ethylene glycol monomethyl ether and ethylene glycol monoethyl ether; Cellosorb acetates such as methyl cellosorb acetate, ethyl cellosorb acetate and diethyl cellosorb acetate; Carbitols such as methyl ethyl carbitol, diethyl carbitol, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol dimethyl ether, diethylene glycol methylethyl ether and diethylene glycol diethyl ether; Propylene glycol alkyl ether acetates such as propylene glycol methyl ether acetate and propylene glycol propyl ether acetate; Aromatic hydrocarbons such as toluene and xylene; Ketones such as methyl ethyl ketone, cyclohexanone, 4-hydroxy-4-methyl-2-pentanone, methyl-n-propyl ketone, methyl-n-butylkenone, methyl-n-amyl ketone and 2-heptanone ; Saturated aliphatic monocarboxylic acid alkyl esters such as ethyl acetate, n-butyl acetate and isobutyl acetate; Lactic acid esters such as methyl lactate and ethyl lactate; Oxy acetic acid alkyl esters such as methyl oxy acetate, oxy ethyl acetate and oxy butyl acetate; Alkoxy acetate alkyl esters, such as methoxy methyl acetate, methoxy ethyl acetate, methoxy butyl acetate, ethoxy methyl acetate, and ethoxy ethyl acetate; 3-oxy propionic acid alkyl esters such as methyl 3-oxy propionate and ethyl 3-oxypropionate; 3-alkoxy propionic acid alkyl esters such as 3-methoxy methyl propionate, 3-methoxy ethyl propionate, 3-ethoxy ethyl propionate and 3-ethoxy methyl propionate; 2-oxy propionic acid alkyl esters such as 2-oxy methyl propionate, 2-oxy ethyl propionate and 2-oxy propionic acid propyl; 2-alkoxy propionic acid alkyl esters such as 2-methoxy methyl propionate, 2-methoxy ethyl propionate, 2-ethoxy ethyl propionate and 2-ethoxy methyl propionate; 2-oxy-2-methyl propionic acid esters, such as 2-oxy-2-methyl methyl propionate and 2-oxy-2-methyl ethyl propionate, 2-methoxy-2-methyl methyl propionate and 2-ethoxy-2- Monooxy monocarboxylic acid alkyl esters of 2-alkoxy-2-methyl propionic acid alkyls such as methyl methyl propionate; Esters such as ethyl 2-hydroxy propionate, ethyl 2-hydroxy-2-methyl propionate, ethyl hydroxy acetate, and methyl 2-hydroxy-3-methyl butanoate; And compounds such as ketone acid esters such as ethyl pyruvate, and N-methylformamide, N, N-dimethylformamide, N-methylformanilade, N-methylacetamide, and N, N-dimethyl Acetamide, N-methylpyrrolidone, dimethyl sulfoxide, benzyl ethyl ether, dihexyl ether, acetyl acetone, isophorone, caproic acid, caprylic acid, 1-octanol, 1-nonanol, benzyl alcohol, acetic acid Benzyl, ethyl benzoate, diethyl oxalate, diethyl maleate, gamma -butyrolactone, ethylene carbonate, propylene carbonate, phenyl cellosorb acetate and the like. Considering compatibility and reactivity among these solvents, glycol ethers such as ethylene glycol monoethyl ether; Ethylene glycol alkylether acetates such as ethyl cellosorb acetate; Esters such as 2-hydroxy ethyl propionate; Diethylene glycols such as diethylene glycol monomethyl ether; More preferable are propylene glycol alkylether acetates such as propylene glycol methylether acetate and propylene glycol propylether acetate.

The solvent is used in an amount of 10 to 1000 parts by weight, preferably 20 to 500 parts by weight based on 100 parts by weight of the pigment. If the content is less than 10 parts by weight, the viscosity of the pigment composition is too large, and if it exceeds 1000 parts by weight, the viscosity of the composition is lowered may affect the physical and optical properties when applying the product.

(F) other additives

In the present invention, a pigment derivative may be used in addition to the pigment as necessary, and the pigment derivative refers to a compound having a pigment derivative or dye substituent group having a sulfonic acid group or a carboxyl group bonded to the pigment. The dye derivatives are generally naphthalene-based, anthraquinone-based, phthalocyanine-based, diketopyrrolopyrrole-based, azo-based pigments or dyes such as sulfonamine salts, sulfone sodium salts, quaternary amine phosphorus salts, alkylamines, triazine derivatives, and the like. Can be used. The amount of the dye derivative can be appropriately adjusted according to the desired physical properties.

Such a green pigment composition according to the first embodiment of the present invention can be usefully used for the color filter in the display device, that is, it can be preferably used in the green pixel portion of the color filter. Accordingly, a second embodiment of the present invention is to provide a color filter made of the green pigment composition of the present invention.

In the green pixel, when the chromaticity is measured by the Yxy colorimeter using a C light source, when y is 0.60, x is in the range of 0.27 to 0.33, and the luminance Y is preferably 55.0 or more, more preferably 55.0 to 59.5. When the color coordinate x is included in the above range, the transmittance is high, the luminance is excellent, and the color reproducibility is excellent, which is preferable.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the following Examples are only preferred examples of the present invention, and the present invention is not limited to the following Examples.

Example 1

Oxide 65 g of phthalocyanine-based green pigment (PG36: manufactured by Clariant, trade name 8G, average particle diameter (D50) 48 nm) and yellow pigment (PY150: manufactured by LANXESS, trade name CHC47235, average particle diameter (D50) 55 nm) 85 g and azo nickel complex compound 0.3 g of silicone (manufactured by Degussa, aerosil 90, average particle diameter (D50), 15 nm, specific surface area: 90 m ² / g), 30 g of dispersant (PB 821, manufactured by Ajinomoto Co., Ltd.) and binder resin (benzyl methacrylate and methacrylic acid) 20 g of this resin copolymerized with 8: 2, Mw = 20,000) was added to a solution dissolved in 799.5 g of propylene glycol methyl ether acetate.

After the mixture was stirred for 30 minutes, the mixture was placed in a circulating bead mill disperser having 300 milliliters of zamber, 0.2 mm zirconium oxide bead filling rate of 70%, and operating at 6.5 m / s. Filtration with a 0.4 micron filter produced a green pigment dispersion composition for color filters having a pigment concentration of 15%.

Comparative Example 1

I did not use silicon oxide Except that was carried out in the same manner as in Example 1.

Comparative Example 2

It carried out similarly to the comparative example 1 except having increased the dispersing agent (PB 821, the Ajinomoto company make) from 30g to 50g in the comparative example 1.

Example 2

90 g of green pigment (PG36: made by Clariant, trade name 8G) and 60 g of yellow pigment (PY138: manufactured by Nippon Ink Chemical Co., Ltd., brand name TDY2) and titanium oxide (Ishihara Corporation, TTO-55A, specific surface area: 40 m ² / g) 1 g was dissolved in a solution in which 30 g of a dispersant (PB 821, manufactured by Ajinomoto Co., Ltd.) and 20 g of a binder resin (resin copolymerized with benzyl methacrylate and methacrylic acid at 8: 2, Mw = 20,000) were dissolved in 799 g of propylene glycol methyl ether acetate. Added.

After the mixture was stirred for 30 minutes, the mixture was placed in a circulating bead mill disperser having 300 milliliters of zamber, 0.2 mm zirconium oxide bead filling rate of 70%, and operating at 6.5 m / s. After filtering with a 0.4 micron filter to prepare a green pigment dispersion composition for color filters having a pigment concentration of 15%.

Comparative Example 3

Except that no titanium oxide is added It carried out similarly to Example 2 above.

Preparation Example 1 Preparation of Resist Composition

The green pigment dispersion composition obtained in Examples 1 to 2 and Comparative Examples 1 to 3 was added to the reactor according to the following composition, stirred for 30 minutes, and then filtered using a 0.4 micron filter to prepare a resist composition.

65 g of green pigment dispersion composition (pigment concentration 15% by weight)

Acrylic photopolymer monomer: DPHA (Dipentaerythritol pentaacrylate) 6 g

Benzyl methacrylate / methacrylic acid copolymer (8/2, acid value 90mgKOH / g) 7g

2 g of epoxy noblock acryl carboxylate resin (product of E1CHEM company)

Photoinitiator: TPP (2-piperonironi-4,6-bis (trichloromethyl) -1,3,5-triazine, Panchim) 0.1 g

Igacure 907 (Shiba Corporation) 0.6g

4,4'-bis (diethylamino) benzophenone (Hodoya Co., Ltd.) 0.2 g

Solvent: Propylene glycol methyl ether acetate 19.0 g

Surfactant: 0.184 g of SH8400 (Toray Corporation)

Test Example 1 Measurement of Stability of Pigment Dispersion Composition

Particle size and viscosity after dispersion using a particle size analyzer (LB 500, Horiba) and a viscometer (DVIII Ultra, Brookfield, Inc.) for color filters prepared in Examples 1 to 2 and Comparative Examples 1 to 3 Are respectively measured and the results for the change over 3 to 14 days are shown in Table 1 below.

After dispersion 3 days 7 days 14 days Particle size (nm) Viscosity (cP) Particle size (nm) Viscosity (cP) Particle size (nm) Viscosity (cP) Particle size (nm) Viscosity (cP) Example 1 56.3 5.63 58.4 5.69 57.3 5.62 59.7 5.80 Comparative Example 1 112.6 20.8 129.8 50.6 285.3 115.3 405.8 Gel Comparative Example 2 64.3 7.83 65.6 7.96 70.7 8.12 79.4 8.86 Example 2 63.8 6.48 65.8 6.53 68.4 6.67 67.8 6.62 Comparative Example 3 126.5 19.4 145.8 30.6 208.6 108.9 504.6 Gel

From Table 1, it can be seen that the pigment dispersion composition of Examples 1 to 2 has a lower particle size and viscosity than the pigment dispersion composition of Comparative Examples 1 to 3, even though it contains a high concentration of the pigment, and over time It can be confirmed that the dispersion stability is excellent compared to Comparative Examples 2 to 3 by being constant without changing the viscosity.

[Test Example 2]: Color difference and luminance measurement

The resist composition obtained in Preparation Example 2 was uniformly coated on a transparent bare glass using a spin coater and then softbaked at 80 ° C. for 90 seconds, and then exposed at 200 mJ using an exposure machine for 30 minutes at 230 ° C. After hardbaking (hard baking), color characteristics (color difference and luminance) were measured using a color difference meter (manufactured by PHOTAL, MCPD3000), and the results are shown in Table 2 below. In addition, the brightness of Example 1 and Comparative Example 1 is also shown in FIG .

x y Y Example 1 0.2963 0.5992 56.5 Comparative Example 1 0.2957 0.5987 56.2 Comparative Example 2 0.2954 0.5983 55.9 Example 2 0.3034 0.6086 57.3 Comparative Example 3 0.3028 0.6078 56.5

 From the results of Table 2 and FIG. 1, the green color filter manufactured using the dispersion composition of Example 1 showed a luminance (Y) of about 0.3 higher than that of Comparative Example 1 without using a dispersion stabilizer, and also a dispersant. It can be seen that the luminance (Y) was about 0.9 higher than that of Comparative Example 2 in which an excessive amount of.

In addition, it can be seen that the green color filter manufactured using the dispersion composition of Example 2 exhibited a luminance Y of about 0.8 higher than that of Comparative Example 2 without using the dispersion stabilizer.

Although the preferred embodiments of the present invention have been described above, the present invention is not limited thereto, and various modifications and changes can be made within the scope of the claims and the detailed description of the invention and the accompanying drawings. Naturally, it belongs to the scope of the invention.

1 is a graph showing the luminance (Y) of the color filter manufactured using the green pigment composition according to Example 1 and Comparative Example 1 of the present invention.

Claims (9)

(A) pigments; (B) binder resin; (C) dispersants; (D) a metal oxide having an average particle diameter of 10 to 50% with respect to the average particle diameter (D50) of the pigment; And (E) a solvent, The content of the (A) pigment, (B) binder resin, (C) dispersant, (D) pigment and (E) To 100 parts by weight of the pigment (A) (B) 1 to 50 parts by weight of the binder resin; (C) 10 to 80 parts by weight of the dispersant; (D) 0.1 to 10 parts by weight of the metal oxide; And (E) Green pigment composition for color filters which is 10-1000 weight part of solvents. delete The method of claim 1, Wherein said metal oxide is selected from the group consisting of silicon oxide, titanium oxide, zinc oxide, magnesium oxide, and combinations thereof. The method of claim 1, The metal oxide is 10 Green pigment composition for a color filter having a specific surface area of to 100m ² / g. The method of claim 1, The average particle diameter (D50) of the pigment is a color pigment green pigment composition for 30 to 100 nanometers. The method of claim 1, The pigment may be a green pigment selected from the group consisting of triphenylmethane, thiazole, phthalocyanine, biolanthrone and combinations thereof; Yellow pigments selected from the group consisting of anthraquinone series, azo series, isoindolin source series, quinoline series, quinophthalone series and combinations thereof; And green pigment composition for a color filter is selected from the group consisting of these. The method of claim 1, Wherein the pigment is in the range of 0.27 to 0.33 when y is 0.60 based on the Yxy color system. The method of claim 1, The binder resin has at least one acidic group, the weight average molecular weight is 5,000 to 40,000 green pigment composition for color filters. The color filter manufactured using the green pigment composition of any one of Claims 1-9.

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